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Свойства воды и водных растворов в миллиметровом и субмиллиметровом диапазоне волн

Журнальные статьи

1.U03136
Amerov A.K., Chen J., Arnold M.A. Molar absorptivities of glucose and other biological molecules in aqueous solutions over the first overtone and combination regions of the near-infrared spectrum // Applied Spectroscopy. 2004. Vol. 58, № 10. P. 1195–1204.

Molar absorptivities are measured for water, glucose, alanine, ascorbate, lactate, triacetin, and urea in the near-infrared spectral region at 37 degreesC. Values are based on the Beer-Lambert law and cover the first overtone (1550-1850 nm; 6450-5400 cm(-1)) and combination (2000-2500 nm; 4000-5000 cm(-1)) spectral windows through aqueous media. Accurate calculations demand accounting for the impact of water displacement upon dissolution of solute. In this regard, water displacement coefficients are measured and reported for each solute. First overtone absorptivities range from 2 to 7 x 10(-5) mM(-1)mm(-1) for all solutes except urea, for which absorptivity values are below 0.5 x 10(-5) mM(-1)mm(-1) across this spectral range. Molar absorptivities over the combination spectral region range from 0.8 to 3.2 x 10(-4) mM(-1)mm(-1), which is a factor of four to five greater than the first overtone absorptivities. Accuracy of the measured values is assessed by comparing calculated or modeled spectra with spectra measured from standard solutions. This comparison reveals accurately modeled spectra in terms of magnitude and position of solute absorption bands. Both actual and modeled spectra from glucose solutions reveal positive and negative absorbance values depending on the measurement wavelength. It is shown that the net absorbance of light is controlled by the magnitude of the absorptivity of glucose compared to the product of the absorptivity of water and the water displacement coefficient for glucose.

2.U46678
Anguelova M.D. Complex dielectric constant of sea foam at microwave frequencies // Journal of Geophysical Research-Oceans. 2008. Vol. 113, № C8. P. C08001.

We present a systematic investigation of the applicability of a group of mixing rules for obtaining the dielectric constant (permittivity) of sea foam ( whitecaps) at microwave frequencies, 1.4 to 37 GHz. By demonstrating that the foam scattering is weak at these frequencies, we justify our interest in basic mixing rules, which do not involve explicit scattering computation, namely, the Maxwell Garnett, Polder-Van Santen, Coherent potential, Looyenga, and Refractive models. The complex dielectric constant of sea foam obtained with these mixing rules is presented and the dependence of foam permittivity on foam void fraction, radiation frequency, sea surface temperature, and salinity is reported. With the exception of the Coherent potential model, all selected mixing rules give reasonable values for the sea foam dielectric constant. To further examine the suitability of a permittivity model for computing the dielectric constant of sea foam, the performance of each mixing rule is evaluated on the basis of three criteria: (1) how well a permittivity model deals with a wide range of void fractions, (2) how a permittivity model behaves approaching the foam-air and foam-water boundaries, and (3) how the choice of a permittivity model affects estimates of emissivity and brightness temperature due to foam. The suitability of the basic mixing rules for computing the complex dielectric constant of sea foam at microwave frequencies can be ranked as: (1) Refractive model, (2) Looyenga model, (3) Maxwell Garnett model, and (4) Polder-Van Santen model.

3.U46678
Anguelova M.D., Webster F. Whitecap coverage from satellite measurements: A first step toward modeling the variability of oceanic whitecaps // J. Geophys. Res.-Oceans. 2006. Vol. 111, № C3. P. C03017.

We present estimates of whitecap coverage on a global scale from satellite-measured brightness temperature of the ocean surface. This is a first step in a larger framework aiming at more realistic modeling of the high variability of whitecap coverage as a function of wind speed and a suite of additional environmental and meteorological factors. The involvement of oceanic whitecaps in various physical and chemical processes important for climate studies such as production of sea-salt aerosols, enhancement of air-sea gas exchange, and influence on retrievals of ocean surface wind and ocean color motivates this effort. A critical review of the physical variables causing the high variability of whitecap coverage and existing approaches modeling this variability establishes the need for a database of whitecap coverage and concomitant measurements of additional factors. The necessity to build such an extensive database justifies the quest for a method estimating whitecap coverage from satellite data. We describe the physical concept, a possible implementation, error analysis, results, and evaluation of a method for estimating whitecap coverage from routine satellite measurements. The advantages of the concept and the drawbacks and necessary improvements of the implementation are discussed.

4.
Arakelyan A.K. et al. Multi-Frequency and Polarimetric Measurements of Perturbed Water Surface Microwave Reflective and Emissive Characteristics by C-, and Ku-Band Combined Scatterometric-Radiometric Systems // Ocean Sensing and Monitoring Ii / ed. Hou W., Arnone R.A. 2010. Vol. 7678. P. 76780C. (SPIE)

In this paper the results of simultaneous and spatially coincident, multi-frequency, polarimetric, spatio-temporally collocated measurements of waved pool water surface microwave reflective ( radar backscattering coefficient) and emissive ( brightness temperature) characteristics angular dependences at 5.6GHz and 15GHz will be represented. Angular measurements were carried out for various water surface roughness parameters at clear air, cloudy and rain conditions. For these measurements C-, and Ku-band, polarimetric, combined scatterometric-radiometric systems were used, set jointly on a mobile buggy moving along the measuring platform. Structures, operational features and the main technical characteristics of the utilized systems are presented too. The paper has an aim as well to attract attention of interested researchers and to invite them to perform their own or joint researches using available devices and facilities.

5.
Arroyo S.T., Martin J. a. S., Garcia A.H. Molecular dynamics simulation of aqueous solutions using interaction energy components: Application to the dielectric properties of the acetone-water system // Molecular Simulation. 2005. Vol. 31, № 8. P. 549–553.

Molecular dynamics simulation of aqueous solution of acetone was made using Lennard - Jones 12- 6- 1 potentials to describe the solute - solvent interactions and TIP4P to describe the water - water interactions. The Morokuma decomposition scheme and the ESIE solute atomic charges were used to reproduce the molecular parameters of the solute - water interaction potential. The results showed that the functions that use the EX- DIS- ES model improve the values of the dielectric properties, in particular, the dielectric constant and the dielectric relaxation time.

6.U08229
Arroyo S.T., Martin J. a. S., Garcia A.H. Thermodynamic and dielectric properties of aqueous solutions using ESIE charges to describe small solutes // Chemical Physics. 2003. Vol. 293, № 2. P. 193–202.

The present paper describes molecular dynamics simulations of aqueous solutions with two solutes of different behaviour in water as formaldehyde and formamide. Lennard-Jones (12-6-1) type potentials obtained from ab initio MP2 level energies corrected with the superposition error basis set were employed to describe the solute-solvent interactions. The Coulomb interactions of these potentials were determined using several sets of solute atomic charges (in gas and solution phase), paying especial attention to the ESIE charges that reproduce the electrostatic component of the solute-water interaction energy. Some properties were evaluated to explain the effect of the solute on the thermodynamic (U-sol, U-rel, DeltaH(sol)), and dielectric (epsilon and tau) response of the evolving medium. Small modifications to the traditional procedures were included in the calculations in order to improve the results.

7.U0309X
Azzam R.M.A. Return-path, multiple-principal-angle, internal-reflection ellipsometer for measuring IR optical properties of aqueous solutions // Applied Optics. 2010. Vol. 49, № 25. P. 4710–4714.

A retroreflection (return-path) spectroscopic ellipsometer without a wave plate is described that uses an IR-transparent high-refractive-index hemicylindrical semiconductor substrate to measure the optical properties of aqueous solutions from multiple principal angles and multiple principal azimuths of attenuated internal reflection (AIR) at the semiconductor-solution interface. The pseudo-Brewster angle of minimum reflectance for the p polarization is also readily measured using the same instrument. This wealth of data can also be used to characterize thin films at the solid-liquid interface. Simulated results of AIR at the Si-water interface over the 1.2-11 mu m IR spectral range are presented in support of this concept. The optical properties of water and aqueous solutions are important for modeling radiative transfer in the atmosphere and oceans and for biomedical and tissue optics.

8.U1905X
Bordi F., Cametti C., Motta A. Scaling behavior of the high-frequency dielectric properties of poly-L-lysine aqueous solutions // Macromolecules. 2000. Vol. 33, № 5. P. 1910–1916.

We report the scaling behavior of the dielectric parameters, the dielectric strength Delta epsilon and the relaxation time tau, of the high-frequency dielectric dispersions observed in aqueous solutions of poly-L-lysine of different molecular weights, from 4000 to 167 000. The dielectric properties have been measured in the frequency range from 1 MHz to 1.8 GHz, and the dispersions have been attributed to internal motions of side chain polar groups, resulting in an intermediate relaxation process between that due to the counterion atmosphere polarization and that due to the orientational polarization of the water molecules. The scaling relationships are compared with the predictions of the dynamic scaling theory recently surveyed by Dobrynin, Colby, and Rubinstein (Macromolecules 1995, 28, 1859) developed to describe both the dilute and semidilute regimes of aqueous polyelectrolyte solutions. Our data, based on the analysis of a new set of dielectric measurements of poly-L-lysine aqueous solutions over an extended range of polymer concentrations and temperatures for each of the molecular weights investigated, are qualitatively consistent with this scaling picture. Deviations from the predicted indices in the power law behavior of the relaxation time in the high molecular weight polymer solutions are briefly discussed.

9.U15646
Boresch S., Willensdorfer M., Steinhauser O. A molecular dynamics study of the dielectric properties of aqueous solutions of alanine and alanine dipeptide // Journal of Chemical Physics. 2004. Vol. 120, № 7. P. 3333–3347.

Molecular dynamics simulations were used to compute the frequency-dependent dielectric susceptibility of aqueous solutions of alanine and alanine dipeptide. We studied four alanine solutions, ranging in concentration from 0.13-0.55 mol/liter, and two solutions of alanine dipeptide (0.13 and 0.27 mol/liter). In accord with experiment we find a strong dielectric increment for both solutes, whose molecular origin is shown to be the zwitterionic nature of the solutes. The dynamic properties were analyzed based on a dielectric component analysis into solute, a first hydration shell, and all remaining (bulk) waters. The results of this three component decomposition were interpreted directly, as well as by uniting the solute and hydration shell component to a "suprasolute" component. In both approaches three contributions to the frequency-dependent dielectric properties can be discerned. The quantitatively largest and fastest component arises from bulk water [i.e., water not influenced by the solute(s)]. The interaction between waters surrounding the solute(s) (the hydration shell) and bulk water molecules leads to a relaxation process occurring on an intermediate time scale. The slowest relaxation process originates from the solute(s) and the interaction of the solute(s) with the first hydration shell and bulk water. The primary importance of the hydration shell is the exchange of shell and bulk waters; the self-contribution from bound water molecules is comparatively small. While in the alanine solutions the solute-water cross-terms are more important than the solute self-term, the solute contribution is larger in the dipeptide solutions. In the latter systems a much clearer separation of time scales between water and alanine dipeptide related properties is observed. The similarities and differences of the dielectric properties of the amino acid/peptide solutions studied in this work and of solutions of mono- and disaccharides and of the protein ubiquitin are discussed.

10.
Byun K., Choi M. Uncertainty of snow water equivalent retrieved from AMSR-E brightness temperature in northeast Asia // Hydrol. Process. 2014. Vol. 28, № 7. P. 3173–3184.

Accurate estimation of snow water equivalent (SWE) has been significantly recognized to improve management and analyses of water resource in specific regions. Although several studies have focused on developing SWE values based on remotely sensed brightness temperatures obtained by microwave sensor systems, it is known that there are still a number of uncertainties in SWE values retrieved from microwave radiometers. Therefore, further research for improving remotely sensed SWE values including global validation should be conducted in unexplored regions such as Northeast Asia. In this regard, we evaluated SWE through comparison of values produced by the Advanced Microwave Scanning Radiometer Earth Observing System (AMSR-E) from December 2002 to February 2011 with in situ SWE values converted from snow-depth observation data from four regions in the South Korea. The results from three areas showed similarities which indicated that the AMSR-E SWE values were overestimated when compared with in situ SWE values, and their Mean Absolute Errors (MAE) by month were relatively small (1.1 to 6.5mm). Contrariwise, the AMSR-E SWE values of one area were significantly underestimated when compared with in situ SWE values and the MAE were much greater (4.9 to 35.2mm). These results were closely related to AMSR-E algorithm-related error sources, which we analyzed with respect to topographic characteristics and snow properties. In particular, we found that snow density data used in the AMSR-E SWE algorithm should be based on reliable in situ data as the current AMSR-E SWE algorithm cannot reflect the spatio-temporal variability of snow density values. Additionally, we derived better results considering saturation effect of AMSR-E SWE. Despite the demise of AMSR-E, this study's analysis is significant for providing a baseline for the new sensor and suggests parameters important for obtaining more reliable SWE.

11.
Cametti C. Dielectric properties of soft-particles in aqueous solutions // Soft Matter. 2011. Vol. 7, № 12. P. 5494–5506.

In this review, we present a summary of the recent theoretical approaches developed in the last few years examining the dielectric and conductometric properties of soft colloidal particles in aqueous solution. Whereas the electrokinetic properties, concerning the movement of soft particles (electrophoretic mobility), have been extensively investigated and rather sophisticated theoretical models have been developed, much less attention has been addressed to the electrical polarization mechanisms induced in these systems by an external electric field, even though the rich phenomenology they present and the chances they offer in the study of their structure and functionality deserve much more interest. We analyze the recent progress achieved in the dielectric and conductometric properties of this kind of colloidal particle aqueous suspensions in the light of the electrokinetic standard model and we discuss in some detail how the structure of the polymer layer might alter the dielectric response of the system, seen as a highly heterogeneous colloidal system. In particular, the limits and the benefits of the soft particle electrokinetic formalism in the understanding the electrostatic features of these systems will be illustrated.

12.
Cametti C. Does Electrical Conductivity of Linear Polyelectrolytes in Aqueous Solutions Follow the Dynamic Scaling Laws? A Critical Review and a Summary of the Key Relations // Polymers. 2014. Vol. 6, № 4. P. 1207–1231.

In this review, we focus on the electrical conductivity of aqueous polyelectrolyte solutions in the light of the dynamic scaling laws, recently proposed by Dobrynin and Rubinstein, to take into account the polymer conformations in different concentration regimes, both in good and poor solvent conditions. This approach allows us to separate contributions due to polymer conformation from those due to the ionic character of the chain, and offers the possibility to extend the validity of the Manning conductivity model to dilute and semidilute regimes. The electrical conductivity in the light of the scaling approach compares reasonably well with the observed values for different polyelectrolytes in aqueous solutions, over an extended concentration range, from the dilute to the semidilute regime.

13.
Cametti C. et al. Dielectric Relaxation Spectroscopy of Lysozyme Aqueous Solutions: Analysis of the delta-Dispersion and the Contribution of the Hydration Water // Journal of Physical Chemistry B. 2011. Vol. 115, № 21. P. 7144–7153.

The dielectric properties of lysozyme aqueous solutions have been investigated over a wide frequency range, from 1 MHz to 50 GHz, where different polarization mechanisms, at a molecular level, manifest. The dielectric relaxation spectra show a multimodal structure, reflecting the complexity of the protein water interactions, made even more intricate with the increase of the protein concentration. The deconvolution of the spectra into their different components is not unambiguous and is generally a delicate process which requires caution. We have analyzed the whole relaxation region, on the basis of the sum of simple Debye-type relaxation functions, considering three main contributions. Particular attention has been payed to the delta-dispersion, intermediate between the beta-dispersion (rotational dynamics of the protein) and the gamma-dispersion (orientational polarization of the water molecules). This intermediate contribution to the dielectric spectrum is attributed to the orientational polarization of water molecules in the immediate vicinity of the protein surface (hydration water). Our measurements clearly demonstrate that, at least at high protein concentrations, the delta-dispersion has a bimodal structure associated with two kinds of hydration water, i.e., tightly bound and loosely bound hydration water. In the concentration range investigated, the existence of a three-modal delta-dispersion, as recently suggested, is not supported, on the basis of statistical tests, by the analysis of the dielectric relaxations we have performed and a bimodal dispersion is accurate enough to describe the experimental data. The amount of the hydration water has been evaluated both from the dielectric parameters associated with the delta-dispersion and from the decrement of the loss peak of the gamma-dispersion. The relative weight of tightly bound and loosely bound hydration water is briefly discussed.

14.
Cametti C., Marchetti S., Onori G. Lysozyme Hydration in Concentrated Aqueous Solutions. Effect of an Equilibrium Cluster Phase // Journal of Physical Chemistry B. 2013. Vol. 117, № 1. P. 104–110.

Water close to proteins plays a key role in determining their structural and functional properties. Despite being a subject of considerable interest, the characterization of hydration water, as far as its total amount is concerned, is still controversial and its influence on protein structure and folding is not yet fully understood. In this work, we have investigated the dielectric properties of lysozyme aqueous solutions over the frequency range where the orientational polarization relaxation of the aqueous phase occurs (from 500 MHz to 50 GHz). Measurements extend over a wide concentration range, up to 300 mg/mL, corresponding to a volume fraction of the order of 0.4. The analysis of the dielectric spectra, based on the decrease of the dielectric increment of the gamma-dispersion as a function of protein concentration, allows us to estimate the total amount of hydration water (both bound water and loosely bound water) present in the system investigated. We observe a decrease of the hydration number as a function of the protein concentration. This behavior is well accounted for by considering the formation of small equilibrium clusters with aggregation number of some units, as recently reported by Stradner et al.(1) on the basis of small-angle X-ray and neutron scattering measurements.

15.U58317
Cametti C., Zuzzi S. Radiowave Dielectric Properties of Sodium Maleate Copolymers in Aqueous Solutions in Light of a Scaling Approach // Journal of Physical Chemistry B. 2010. Vol. 114, № 21. P. 7140–7147.

The concentration dependence of the dielectric properties of aqueous solutions of sodium maleate copolymers with comonomers of different hydrophobicities have been investigated by means of frequency domain dielectric spectroscopy in the frequency range from 1 kHz to 2 GHz. The dielectric relaxation falling between the process at low frequencies (polarization involving the whole polymer chain) and the one at high frequencies (polarization of the bulk aqueous phase) has been analyzed in light of the scaling properties of polyelectrolyte solutions. Within this framework, the dielectric properties are governed by two characteristic lengths, the distance R(cm) between chains in the dilute regime and the correlation length xi in the semidilute regime. We find that, for both these regimes, the exponents of the scaling laws, which describe the dielectric increment Delta epsilon and the relaxation time tau(ion) are in a reasonably good agreement with the ones experimentally observed. This analysis gives further support to the scaling approach of the dynamic behavior of polyelectrolytes, appearing very suitable to modeling our dielectric results.

16.
Deng S. et al. Generalized image charge solvation model for electrostatic interactions in molecular dynamics simulations of aqueous solutions // Journal of Computational Physics. 2013. Vol. 245. P. 84–106.

This paper extends the image charge solvation model (ICSM) [Y. Lin, A. Baumketner, S. Deng, Z. Xu, D. Jacobs, W. Cai, An image-based reaction field method for electrostatic interactions in molecular dynamics simulations of aqueous solutions, J. Chem. Phys. 131 (2009) 154103], a hybrid explicit/implicit method to treat electrostatic interactions in computer simulations of biomolecules formulated for spherical cavities, to prolate spheroidal and triaxial ellipsoidal cavities, designed to better accommodate non-spherical solutes in molecular dynamics (MD) simulations. In addition to the utilization of a general truncated octahedron as the MD simulation box, central to the proposed extension is an image approximation method to compute the reaction field for a point charge placed inside such a non-spherical cavity by using a single image charge located outside the cavity. The resulting generalized image charge solvation model (GICSM) is tested in simulations of liquid water, and the results are analyzed in comparison with those obtained from the ICSM simulations as a reference. We find that, for improved computational efficiency due to smaller simulation cells and consequently a less number of explicit solvent molecules, the generalized model can still faithfully reproduce known static and dynamic properties of liquid water at least for systems considered in the present paper, indicating its great potential to become an accurate but more efficient alternative to the ICSM when bio-macromolecules of irregular shapes are to be simulated.

17.
Domine F. et al. Snow physics as relevant to snow photochemistry // Atmos. Chem. Phys. 2008. Vol. 8, № 2. P. 171–208.

Snow on the ground is a complex multiphase photochemical reactor that dramatically modifies the chemical composition of the overlying atmosphere. A quantitative description of the emissions of reactive gases by snow requires knowledge of snow physical properties. This overview details our current understanding of how those physical properties relevant to snow photochemistry vary during snow metamorphism. Properties discussed are density, specific surface area, thermal conductivity, permeability, gas diffusivity and optical properties. Inasmuch as possible, equations to parameterize these properties as functions of climatic variables are proposed, based on field measurements, laboratory experiments and theory. The potential of remote sensing methods to obtain information on some snow physical variables such as grain size, liquid water content and snow depth are discussed. The possibilities for and difficulties of building a snow photochemistry model by adapting current snow physics models are explored. Elaborate snow physics models already exist, and including variables of particular interest to snow photochemistry such as light fluxes and specific surface area appears possible. On the other hand, understanding the nature and location of reactive molecules in snow seems to be the greatest difficulty modelers will have to face for lack of experimental data, and progress on this aspect will require the detailed study of natural snow samples.

18.
Dubina A.I., Pirogov Y.A. Thermal millimeter wave radiation of a perturbed water surface // International Journal of Infrared and Millimeter Waves. 2006. Vol. 27, № 6. P. 889–902.

This article is devoted to the thermal radio emission of the disturbed water surface in a small-scale approximation. It describes the numerical calculation method of surface emittance with an arbitrary number of surface waves based on the small perturbation method and boundary conditions of Leontovich. There are description and some results of the experimental test of this method as well.

19.
Eiberweiser A. et al. Ion Hydration and Association in Aqueous Potassium Phosphate Solutions // J. Phys. Chem. B. 2015. Vol. 119, № 16. P. 5270–5281.

Ionic hydration and ion association in aqueous solutions of KH2PO4, K2HPO4, and K3PO4 at 25 °C up to high concentrations have been investigated using dielectric relaxation spectroscopy (DRS). The three phosphate anions were found to be extensively hydrated, with total hydration numbers at infinite dilution of ~11 (for H2PO4-), ~20 (HPO42-), and ~39 (PO43-). These values are indicative of the existence of a second hydration shell around HPO42- and especially PO43-. Two types of hydrating water molecules could be quantified: irrotationally bound (ib, H2O molecules essentially "frozen" on the DRS time scale) and "slow" (loosely bound water molecules with identifiably slower dynamics than bulk water). For H2PO42- over the entire concentration range and for H2PO42- and PO43- at concentrations c ? 1 mol L-1, only ?slow? H2O was detected; however, at higher concentrations of the latter two anions, an increasing fraction of ib water appears, making up ?50% of the total hydration number close to the saturation limit of K2HPO4. Contrary to common belief, all three salts showed significant ion pair formation, with standard association constants of the 1:1 species increasing in the order: KH2PO40(aq) < KHPO4?(aq) < KPO42?(aq). The main type of ion pair in solution shifted from solvent-shared ion pairs (SIPs) to double-solvent-separated ion pairs (2SIPs) in the same sequence.

20.001624
Gamze E. Voltammetric Determination of Methidathion Insecticide // Журнал аналитической химии. 2006. Т. 61. № 7. С. 729-732.

Abstract-An electroanalytical method has been developed for the determination of methidathion by square-wave voltammetry on a Nafion®-coated glassy carbon electrode in aqueous solutions with 0.05 M acetate buffer as a supporting electrolyte. The best voltammetric conditions were found to be pH 4.0, a preconcentration po-tential of 0.45 V, and a preconcentration time of 60 s. The experimental parameters, such as pH, film thickness, preconcentration potential, preconcentration time, and square-wave voltammetric parameters were optimized. Us-ing this method, the calibration curve is linear in the range 5 x 10-8-7 x 10-7 M with a detection limit (S/N = 3) of 30 nM.

21.
Griffith J.H., Scheraga H.A. Statistical thermodynamics of aqueous solutions. I. Water structure, solutions with non-polar solutes, and hydrophobic interactions // Theochem-J. Mol. Struct. 2004. Vol. 682, № 1-3. P. 97–113.

A statistical thermodynamic theory of the structure and thermodynamic properties of liquid water is needed for a description of the thermodynamics properties of aqueous salt solutions. For this purpose, such a theory, developed earlier by N6methy and Scheraga, has been modified by removing an empirical cluster restriction, by using a different form of the partition function for unbonded water, by treating the librational and translational frequencies differently, and by removing the restriction that the energy levels are equally spaced. These modifications improved the computed thermodynamic properties of liquid H2O and D2O, and provide a basis to treat aqueous solutions of non-polar molecules and, subsequently, salts. The presence of a non-polar solute leads to shifts of the energy levels of the variously bonded species in the first layer of the surrounding water molecules, and a resulting increase in the fraction of hydrogen bonds between water molecules; i.e. non-polar solutes in aqueous solutions can be characterized as 'structure making'. Theoretical, Monte Carlo and molecular dynamics calculations, and also simplified models, in the literature, support the assumption in the model used here of a partial cage-like (hydrogen-bonded) structure around a hydrocarbon molecule (hydrophobic hydration). The computed thermodynamic parameters for the transfer of hydrocarbons from a non-polar medium to an aqueous environment, based on a statistical thermodynamic treatment, are reproduced very well by the theory. With no additional parameters, the theory accounts qualitatively for the transfer of argon, propane and butane, respectively, from H2O to D2O, better than the original theory. The strengths of pairwise hydrophobic interactions, computed by Nemethy and Scheraga, and subsequently verified experimentally, are not altered by the modification of the earlier theory for liquid water. (C) 2004 Elsevier B.V. All rights reserved.

22.
Grigoryan M.L. et al. Clouds and Rain Effects on Perturbed Water Surface Microwave Reflection and Emission at 37GHz // Ocean Sensing and Monitoring Ii / ed. Hou W., Arnone R.A. 2010. Vol. 7678. P. 76780D. (SPIE)

In this paper the structure and operational features of K(a)-band, combined scatterometric-radiometric system and the results of spatio-temporally collocated measurements of perturbed pool water surface microwave reflective ( radar backscattering coefficient) and emissive ( brightness temperature) characteristics angular dependences at similar to 37GHz are presented, curried out under clear air, heavy clouds and rain conditions.

23.
Jin W. et al. A new algorithm for sea-surface wind-speed retrieval based on the L-band radiometer onboard Aquarius // Chin. J. Oceanol. Limnol. 2015. Vol. 33, № 5. P. 1115–1123.

Aquarius is the second satellite mission to focus on the remote sensing of sea-surface salinity from space and it has mapped global sea-surface salinity for nearly 3 years since its launch in 2011. However, benefiting from the high atmospheric transparency and moderate sensitivity to wind speed of the L-band brightness temperature (TB), the Aquarius L-band radiometer can actually provide a new technique for the remote sensing of wind speed. In this article, the sea-surface wind speeds derived from TBs measured by Aquarius' L-band radiometer are presented, the algorithm for which is developed and validated using multisource wind speed data, including WindSat microwave radiometer and National Data Buoy Center buoy data, and the Hurricane Research Division of the Atlantic Oceanographic and Meteorological Laboratory wind field product. The error analysis indicates that the performance of retrieval algorithm is good. The RMSE of the Aquarius wind-speed algorithm is about 1 and 1.5 m/s for global oceans and areas of tropical hurricanes, respectively. Consequently, the applicability of using the Aquarius L-band radiometer as a near all-weather wind-speed measuring method is verified.

24.
Kaatze U. Bound water: Evidence from and implications for the dielectric properties of aqueous solutions // Journal of Molecular Liquids. 2011. Vol. 162, № 3. P. 105–112.

Broadband dielectric spectra of a variety of aqueous solutions are evaluated as to indications of water that may be considered bound. Static permittivity decrements due to depolarizing internal electric fields, from kinetic depolarization, as well as from dielectric saturation are discussed. The latter effect reflects the preferential orientation of water permanent dipole orientations within strong Coulombic field of small ions, especially multivalent cations. Such water may be considered bound even though rapid rotations around the orientation of the electric dipole moment are definitely possible and also a fast exchange of water molecules between the hydration region and the bulk may take place. Water exhibiting large dielectric relaxation times, as typical for regions with large local concentration of foreign matter, may also be named bound. However, no clear evidence for interaction energies exceeding the hydrogen bond energy of pure water has been found. Rather enhanced relaxation times at low water content reflect the small concentration of hydrogen bonding sites and thus low probability density for the formation of a new hydrogen bond. Potential interferences of the water relaxation with relaxations from other molecules or from ionic structures are mentioned briefly.

25.00228X
Komyak V.A., Shilo S.A. Manifestations of the spatial nonuniformity and azimuthal anisotropy of sea waves in the microwave thermal radiation of the sea surface // Известия РАН, серия Физика атмосферы и океана. 2002. Vol. 38, № 2. P. 267-272.

The article discusses the effect of nonstationary processes in developing sea waves, such as spatial variations in wind speed, multimode behavior of sea waves, and azimuthal anisotropy of slopes (spectrum of sea waves), on the radio-brightness temperature of the sea surface in the millimeter wave range. Experimental data are compared to model computations. With the use of model considerations, an effort is made to explain the features observed experimentally in the elevation dependence of the azimuthal anisotropy of the sea surface radio-brightness temperature.

26.U17641
Kunz A.-P.E., van Gunsteren W.F. Development of a Nonlinear Classical Polarization Model for Liquid Water and Aqueous Solutions: COS/D // Journal of Physical Chemistry A. 2009. Vol. 113, № 43. P. 11570–11579.

A new charge-on-spring (COS) model for water is introduced (COS/D). It includes a sublinear dependence of the induced dipole on the electric field for large field strength to include the effect,of hyperpolarizability by damping the polarizability. Only two new parameters were introduced to define the damping of the polarizability. In the parametrization procedure, these two damping parameters, the two Lennard-Jones parameters, the charge on the oxygen, and the distance between the virtual site and the oxygen atom were varied to reproduce the density, the heat of vaporization, the dielectric permittivity, and the position of the first peak in the radial distribution function of liquid water at room temperature and pressure. In this way, a model was obtained that correctly describes a-variety of thermodynamic, dynamic, and dielectric properties of water while still preserving the simplicity of the COS model, which allows a straightforward introduction of explicit polarization into (bio)molecular force fields.

27.
Lahoz W.A., De Lannoy G.J.M. Closing the Gaps in Our Knowledge of the Hydrological Cycle over Land: Conceptual Problems // Surv. Geophys. 2014. Vol. 35, № 3. P. 623–660.

This paper reviews the conceptual problems limiting our current knowledge of the hydrological cycle over land. We start from the premise that to understand the hydrological cycle we need to make observations and develop dynamic models that encapsulate our understanding. Yet, neither the observations nor the models could give a complete picture of the hydrological cycle. Data assimilation combines observational and model information and adds value to both the model and the observations, yielding increasingly consistent and complete estimates of hydrological components. In this review paper we provide a historical perspective of conceptual problems and discuss state-of-the-art hydrological observing, modelling and data assimilation systems.

28.
Liao X. et al. Dielectric properties of lysine aqueous solutions at 2450 MHz // Journal of Molecular Liquids. 2003. Vol. 107, № 1-3. P. 15–19.

Dielectric properties of lysine aqueous solutions at 2450 MHz were investigated at concentrations ranging from 9 to 37% (by weight) at 25 degreesC using a cavity perturbation technique. Dielectric constant decreased with an increase in concentration. Loss factor increased with an increase in concentration in the range of 9 - 31% and keeps constant in the range of 31-37%. The value of the loss factor was less than I at higher concentrations. Regression models were generated to link the dielectric properties to concentration. The results can be used in estimating the volumetric heating of these solutions by microwave energy, studying the dielectric behavior of the lysine solutions, and optimizing the chemical reactions involving lysine aqueous solutions in a microwave field.

29.
Liao X. et al. DIELECTRIC PROPERTIES OF SUPERSATURATED alpha-D-GLUCOSE AQUEOUS SOLUTIONS AT 2450 MHZ // Journal of Microwave Power and Electromagnetic Energy. 2001. Vol. 36, № 3. P. 131–138.

Dielectric properties of supersaturated alpha-D-glucose aqueous solutions (45-56% w/w) at 2.45 GHz were investigated at temperatures ranging from 25 degrees C to 85 degrees C. Penetration depth was calculated as well. At each temperature tested, there exists a concentration range at which the dielectric constants or loss factors for supersaturated glucose solutions are independent of concentration. These results will be helpful in studies of the Maillard reaction as it occurs in a microwave field.

30.
Liao X.J. et al. Dielectric properties of alpha-D-glucose aqueous solutions at 2450 MHz // Food Research International. 2003. Vol. 36, № 5. P. 485–490.

Using a cavity perturbation technique, dielectric properties of alpha-D-glucose aqueous solution at 2450 MHz were measured at, concentrations ranging from 10 to 60% in the temperature range of 0-70 degreesC. Dielectric constant increases with temperature in a quadratic manner while linearly decreasing with glucose concentration. Dielectric loss factor decreases with temperature in a quadratic way. The loss factor-concentration relationship depends on the temperature. At lower temperature, loss factor increases linearly with concentration up to a certain concentration then decreases. At temperatures higher than 40 degreesC, loss factor linearly increases with concentration at all concentration ranges studied. The results are useful for studying volumetric heating of these solutions by microwave energy, and chemical changes such as Maillard reaction and mutarotation involving glucose aqueous solutions in microwave field.

31.
Liao X.J., Raghavan G.S.V., Yaylayan V.A. Dielectric properties of aqueous solutions of alpha-D-glucose at 915 MHz // Journal of Molecular Liquids. 2002. Vol. 100, № 3. P. 199–205.

Using a cavity perturbation technique, dielectric properties of aqueous Solutions of alpha-D-glucose at 915 MHz were investigated at concentrations varying from 10 to 70% (w/w) and temperatures ranging from 25-85degreesC. The dielectric constant increased with temperature but decreased with concentration, whereas the loss factor did the inverse. Dielectric properties for higher concentration glucose solutions showed the greatest variation at higher temperatures. Predictive models of the dielectric properties as functions of concentration and temperature were developed by stepwise regression. Such models are useful in estimating the volumetric heating of these solutions by microwave energy, studying the dielectric behavior of the glucose solutions, and chemical reactions involving glucose in aqueous solutions in a microwave field.

32.
Lileev A., Lyashchenko A. Dielectric properties of ammonium salt aqueous solutions // Journal of Molecular Liquids. 2009. Vol. 150, № 1-3. P. 4–8.

High-frequency dielectric permittivity, dielectric losses and low-frequency conductivity of aqueous solutions of ammonium salts (NH(4)NO(3), NH(4)BF(4). NH(4)ClO(4), NH(4)SO(3)NH(2), NH(4)HSO(4), (NH(4))(2)SO(4), and NH(4)SCN) were measured at 288, 298 and 308 K. The parameters of the process of the dielectric relaxation (i.e. time tau and enthalpy of activation Delta H(epsilon)(++)) were calculated. These values characterize the mobility of water molecules in solutions. The structure-breaking effect is found for all investigated ammonium salts. The variation of this effect for different anions in dependence on factors determining the molecular-kinetic hydration of ions (form, size, charge, etc.) is established.

33.
Liu C., Zhao K. Effects of Concentration and Temperature on the Dynamic Behavior of PAA-g-PEO Aqueous Solutions with Different Counterion Species: A Dielectric Spectroscopy Study // Journal of Physical Chemistry B. 2012. Vol. 116, № 2. P. 763–774.

Dielectric properties of PAA-g-PEO-7% solutions with different counterions were measured as a function of concentration and temperature over a frequency range of 40 Hz to 110 MHz. After the contribution of electrode polarization effects was subtracted, the dielectric spectra of PAA-g-PEO-7% solutions showed three relaxation processes in the experimental frequency range, named low-, mid-, and high-frequency relaxation. The observed three relaxations were strictly analyzed by using the Cole-Cole relaxation function, and the dielectric parameters (dielectric increment Delta epsilon and the relaxation time tau) were obtained. The scaling relation of dielectric increment and relaxation time of high frequency with concentration C(p) were obtained and compared with the predictions of scaling theories. The information on the dynamics and microstructure of PAA-g-PEO-7% was obtained. Using different counterion species, the mid- and high-frequency relaxation mechanisms were attributed to the fluctuation of condensed counterions and free counterions, respectively, and the low-frequency relaxation was considered to be caused by the interface polarization of a complex formed by the hydrogen bonding between carboxylic group of PAA and ether oxygen on the side-chain PEO. In addition, by means of Eyring equation, the thermodynamic parameters, enthalpy change Delta H and entropy change Delta S, of the three relaxations were calculated from the relaxation time and discussed from the microscopic thermodynamical view.

34.
Lyashchenko A., Lileev A. Dielectric Relaxation of Water in Hydration Shells of Ions // Journal of Chemical and Engineering Data. 2010. Vol. 55, № 5. P. 2008–2016.

Microwave spectroscopy has been used to study the dielectric properties of aqueous electrolyte solutions over a wide range of concentrations, the frequency range (7 to 25 or 7 to 120) GHz, and the temperature range (283 to 313 or 288 to 308) K. The static dielectric permittivity, dielectric relaxation time, and activation enthalpy have been calculated for 46 binary systems. General relations between dielectric relaxation parameters and structural effects in aqueous salt solutions are considered. The increase in the order of complementary structural organization for water in the bulk and hydration shells of ions gives rise to the molecular-kinetic stabilization of water and to the structure-making effect. This explains the difference between dielectric relaxation characteristics for a wide variety of electrolyte solutions. We present systematic dielectric data for aqueous electrolytes with hydrophilic and hydrophobic hydration of cations and anions. The temperature effect is also examined. On the basis of this study, new criteria for the difference between hydrophilic and hydrophobic hydration of ions are suggested.

35.
Lyashchenko A.K., Novskova T.A. Structural dynamics of water and its dielectric and absorption spectra in the range 0-800 cm(-1) // J. Mol. Liq. 2006. Vol. 125, № 2-3. P. 130–138.

A structural dynamics model is suggested that describes the complex permittivity and absorption spectra of water over the entire range of orientation polarization, 0 < v < 800 cm(-1). The mechanism of elementary motion of water molecules involves partial "dissociation" of some fragments of the tetrahedral network. Structural fragments are differentiated in which molecules rotate about different axes and have different moments of inertia. The experimental complex permittivity and absorption spectra were described using the confined rotator (I)/.../ confined rotator (N) theoretical scheme. The frequency boundary between the collective Debye process and quasi-resonant processes related to elementary water motions was thereby determined. The common features and differences between the spectra of ordinary and heavy water are explained for the entire frequency range. This data made it possible to provide a new interpretation of the band at similar to 200 cm(-1). Spectral trends in the frequency range 5 < v < 200 cm(-1) are steered by the structural transitions of separate molecules and dimers realized in rotational-translational diffusion processes.

36.
Maass N. et al. Validation of SMOS sea ice thickness retrieval in the northern Baltic Sea // Tellus Ser. A-Dyn. Meteorol. Oceanol. 2015. Vol. 67. P. 24617.

The Soil Moisture and Ocean Salinity (SMOS) mission observes brightness temperatures at a low microwave frequency of 1.4 GHz (L-band) with a daily coverage of the polar regions. L-band radiometry has been shown to provide information on the thickness of thin sea ice. Here, we apply a new emission model that has previously been used to investigate the impact of snow on thick Arctic sea ice. The model has not yet been used to retrieve ice thickness. In contrast to previous SMOS ice thickness retrievals, the new model allows us to include a snow layer in the brightness temperature simulations. Using ice thickness estimations from satellite thermal imagery, we simulate brightness temperatures during the ice growth season 2011 in the northern Baltic Sea. In both the simulations and the SMOS observations, brightness temperatures increase by more than 20 K, most likely due to an increase of ice thickness. Only if we include the snow in the model, the absolute values of the simulations and the observations agree well (mean deviations below 3.5 K). In a second comparison, we use high-resolution measurements of total ice thickness (sum of ice and snow thickness) from an electromagnetic (EM) sounding system to simulate brightness temperatures for 12 circular areas. While the SMOS observations and the simulations that use the EM modal ice thickness are highly correlated (r(2) = 0.95), the simulated brightness temperatures are on average 12 K higher than observed by SMOS. This would correspond to an 8-cm overestimation of the modal ice thickness by the SMOS retrieval. In contrast, if the simulations take into account the shape of the EM ice thickness distributions (r(2) = 0.87), the mean deviation between simulated and observed brightness temperatures is below 0.1 K.

37.U08248
Marcus Y. Effect of Ions on the Structure of Water: Structure Making and Breaking // Chemical Reviews. 2009. Vol. 109, № 3. P. 1346–1370.

38.
Marcus Y. Evaluation of the Static Permittivity of Aqueous Electrolytes // Journal of Solution Chemistry. 2013. Vol. 42, № 12. P. 2354–2363.

The static (relative) permittivity of aqueous electrolyte solutions at 25 °C, ?(? = 0) where ? is the frequency of the external field, has been obtained from the literature. The limiting dielectric decrements ? = ? lim(c > 0)d?/dc, where c is the electrolyte concentration (? 1 mol·dm?3), are tabulated. The most appropriate additive individual ionic ? i values are derived. The effect of ion pairing in the solutions is briefly discussed.

39.
Martin A.C.H. et al. Active-passive synergy for interpreting ocean L-band emissivity: Results from the CAROLS airborne campaigns // J. Geophys. Res.-Oceans. 2014. Vol. 119, № 8. P. 4940–4957.

The impact of the ocean surface roughness on the ocean L-band emissivity is investigated using simultaneous airborne measurements from an L-band radiometer (CAROLS) and from a C-band scatterometer (STORM) acquired in the Gulf of Biscay (off-the French Atlantic coasts) in November 2010. Two synergetic approaches are used to investigate the impact of surface roughness on the L-band brightness temperature (Tb). First, wind derived from the scatterometer measurements is used to analyze the roughness contribution to Tb as a function of wind and compare it with the one simulated by SMOS and Aquarius roughness models. Then residuals from this mean relationship are analyzed in terms of mean square slope derived from the STORM instrument. We show improvement of new radiometric roughness models derived from SMOS and Aquarius satellite measurements in comparison with prelaunch models. Influence of wind azimuth on Tb could not be evidenced from our data set. However, we point out the importance of taking into account large roughness scales (>20 cm) in addition to small roughness scale (5 cm) rapidly affected by wind to interpret radiometric measurements far from nadir. This was made possible thanks to simultaneous estimates of large and small roughness scales using STORM at small (7-16 degrees) and large (30 degrees) incidence angles.

40.U40351
Paluch M. Electrical properties of free surface of water and aqueous solutions // Adv. Colloid Interface Sci. 2000. Vol. 84, № 1-3. P. 27–45.

The investigations, both experimental and theoretical, concerning the sign and the magnitude of the surface potential drop at the water/air interface and across adsorbed films presented in many papers are surveyed.

41.
Panpan Y. et al. Satellite retrieval of hurricane wind speeds using the AMSR2 microwave radiometer // Chin. J. Oceanol. Limnol. 2015. Vol. 33, № 5. P. 1104–1114.

The AMSR2 microwave radiometer is the main payload of the GCOM-W1 satellite, launched by the Japan Aerospace Exploration Agency in 2012. Based on the pre-launch information extraction algorithm, the AMSR2 enables remote monitoring of geophysical parameters such as sea surface temperature, wind speed, water vapor, and liquid cloud water content. However, rain alters the properties of atmospheric scattering and absorption, which contaminates the brightness temperatures measured by the microwave radiometer. Therefore, it is difficult to retrieve AMSR2-derived sea surface wind speeds under rainfall conditions. Based on microwave radiative transfer theory, and using AMSR2 L1 brightness temperature data obtained in August 2012 and NCEP reanalysis data, we studied the sensitivity of AMSR2 brightness temperatures to rain and wind speed, from which a channel combination of brightness temperature was established that is insensitive to rainfall, but sensitive to wind speed. Using brightness temperatures obtained with the proposed channel combination as input parameters, in conjunction with HRD wind field data, and adopting multiple linear regression and BP neural network methods, we established an algorithm for hurricane wind speed retrieval under rainfall conditions. The results showed that the standard deviation and relative error of retrievals, obtained using the multiple linear regression algorithm, were 3.1 m/s and 13%, respectively. However, the standard deviation and relative error of retrievals obtained using the BP neural network algorithm were better (2.1 m/s and 8%, respectively). Thus, the results of this paper preliminarily verified the feasibility of using microwave radiometers to extract sea surface wind speeds under rainfall conditions.

42.
Penkov N. et al. Terahertz Spectroscopy Applied for Investigation of Water Structure // J. Phys. Chem. B. 2015. Vol. 119, № 39. P. 12664–12670.

The absorption spectra of liquid water and various aqueous solutions were analyzed in a terahertz frequency domain (from 6 to 200 cm(-1)) which characterize the collective dynamics of water molecules. Particular attention was paid to the relaxation process iii the tange of, similar to 6-80 cm(-1). The physical essence of this process on the molecular level is still unclear. We found that the amplitude of this relaxation process correlates with the degree of destruction of water structure. The obtained data allowed us to interpret this process as a thonomolecular relaxation of free water molecules. On the basis of a consideration of the water polarization in the electric field, we proposed a method of calculation of the amount of free water molecules in solution.

43.
Pour H.K. et al. Impact of satellite-based lake surface observations on the initial state of HIRLAM. Part I: evaluation of remotely-sensed lake surface water temperature observations // Tellus Ser. A-Dyn. Meteorol. Oceanol. 2014. Vol. 66. P. 21534.

Lake Surface Water Temperature (LSWT) observations are used to improve the lake surface state in the High Resolution Limited Area Model (HIRLAM), a three-dimensional numerical weather prediction (NWP) model. In this paper, satellite-derived LSWT observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Along-Track Scanning Radiometer (AATSR) are evaluated against in-situ measurements collected by the Finnish Environment Institute (SYKE) for a selection of large-to medium-size lakes during the open-water season. Data assimilation of these LSWT observations into the HIRLAM is in the paper Part II. Results show a good agreement between MODIS and in-situ measurements from 22 Finnish lakes, with a mean bias of -1.13 degrees C determined over five open-water seasons (2007-2011). Evaluation of MODIS during an overlapping period (2007-2009) with the AATSR-L2 product currently distributed by the European Space Agency (ESA) shows a mean (cold) bias error of -0.93 degrees C for MODIS and a warm mean bias of 1.08 degrees C for AATSR-L2. Two additional LSWT retrieval algorithms were applied to produce more accurate AATSR products. The algorithms use ESA's AATSR-L1B brightness temperature product to generate new L2 products: one based on Key et al. (1997) and the other on Prata (2002) with a finer resolution water mask than used in the creation of the AATSR-L2 product distributed by ESA. The accuracies of LSWT retrievals are improved with the Key and Prata algorithms with biases of 0.78 degrees C and -0.11 degrees C, respectively, compared to the original AATSR-L2 product (3.18 degrees C).

44.
Richardson M., Davenport I., Gurney R. Global Snow Mass Measurements and the Effect of Stratigraphic Detail on Inversion of Microwave Brightness Temperatures // Surv. Geophys. 2014. Vol. 35, № 3. P. 785–812.

Snow provides large seasonal storage of freshwater, and information about the distribution of snow mass as snow water equivalent (SWE) is important for hydrological planning and detecting climate change impacts. Large regional disagreements remain between estimates from reanalyses, remote sensing and modelling. Assimilating passive microwave information improves SWE estimates in many regions, but the assimilation must account for how microwave scattering depends on snow stratigraphy. Physical snow models can estimate snow stratigraphy, but users must consider the computational expense of model complexity versus acceptable errors. Using data from the National Aeronautics and Space Administration Cold Land Processes Experiment and the Helsinki University of Technology microwave emission model of layered snowpacks, it is shown that simulations of the brightness temperature difference between 19 and 37 GHz vertically polarised microwaves are consistent with advanced microwave scanning radiometer-earth observing system and special sensor microwave imager retrievals once known stratigraphic information is used. Simulated brightness temperature differences for an individual snow profile depend on the provided stratigraphic detail. Relative to a profile defined at the 10-cm resolution of density and temperature measurements, the error introduced by simplification to a single layer of average properties increases approximately linearly with snow mass. If this brightness temperature error is converted into SWE using a traditional retrieval method, then it is equivalent to +/- 13 mm SWE (7 % of total) at a depth of 100 cm. This error is reduced to +/- 5.6 mm SWE (3 % of total) for a two-layer model.

45.
Routray W., Orsat V. Variation of dielectric properties of aqueous solutions of ethanol and acids at various temperatures with low acid concentration levels // Physics and Chemistry of Liquids. 2014. Vol. 52, № 2. P. 209–232.

Microwave-assisted extraction is gaining in popularity for the production of plant extracts and the dielectric properties determine the behaviour of different materials in a microwave environment; hence the measurement of the dielectric properties of different solvents used for analytical purposes and the interpretation of their heating rate can help in minimising the time and solvent consumption. In this study, the dielectric constant and dielectric loss of different combinations (generated using central composite design (CCD)) of ethanol concentrations and acid (HCl and citric acid) at different temperature levels were measured at frequencies varying from 0.5 GHz to 6 GHz, and the dissipation factor and depth of penetration were calculated for the respective cases, which were analysed for the interpretation of heating rates of the different solvent combinations. Overall, for all the responses (observed and calculated), ethanol concentration levels and temperature levels were found to be the most significant factors; it was interpreted and observed that the heating rate increases with an increase in ethanol concentration and decreases with increasing temperature. In general, the dissipation factor was interpreted to increase with increase in acid concentration (observed from screening analysis); however, citric acid concentration was found to have an insignificant effect on the dissipation factor (as interpreted from CCD with response surface methodology (CCD-RSM)), and hence was found to have insignificant contribution to the heating rate at lower concentrations. In case of CCD-RSM analysis of the values of dissipation factor for the combinations of ethanol with HCl, the effect of acid concentration on the dissipation factor was found to be significant; however, it was still found to be negligible when the solvent combinations were heated in the microwave reactor.

46.
Symons M.C.R. Spectroscopy of aqueous solutions: protein and DNA interactions with water // Cell. Mol. Life Sci. 2000. Vol. 57, № 7. P. 999–1007.

This review emphasises the need to use spectroscopy in order to understand the behaviour of water, and summarises the background of the subject. The various forms of spectroscopy that are especially informative are described, with particular reference to near-infrared (NIR) spectrophotometry. The key results are outlined, first those obtained with small molecules and ions, and second those involving proteins, DNA and cell membranes. Finally, some interpretations are offered which include the novel but possibly controversial concept of free OH and free lone-pair groups.

47.U1905X
Takemasa M., Chiba A., Date M. Counterion dynamics of kappa- and iota-carrageenan aqueous solutions investigated by the dielectric properties // Macromolecules. 2002. Vol. 35, № 14. P. 5595–5600.

The temperature dependence of the dielectric properties of k- and i-carrageenan aqueous solutions with various counterion species, K, Ca, and Na, were investigated over the frequency range 10(-2)-10(6) Hz and the temperature range 2.0-80.0 degreesC. In the case of x-carrageenan solutions, just below the coil-to-helix transition temperature, T-CH, the de conductivity sharply decreases within a few degrees of temperature. In contrast, the sharp decrease was not observed for i-carrageenan solutions. The dielectric relaxation process with the relaxation time similar to100 mus, which can be assigned to the counterion fluctuation in the parallel direction to the helical axis, arises below TCH. Just below TCH, the relaxation strength increases sharply with decreasing temperature for both the carrageenan type with all the counterion species exhibiting the coil-to-helix transition, reaching similar to10(3) at the temperatures far below TCH. These findings indicate that the counterions are tightly bound to helical molecules due to an increase of the charge density along the helical axis during the coil-helix transition. The relaxation time reflecting the fluctuation distance increases sharply in the initial stage of gelation and gradually reaches a constant value. We think that the formation of the high charge density region, which is connected with the aggregated region of helices, is determined by which process, a growth of the length of the helices or the aggregation of the helices; precedes in the initial stage of gelation.

48.
Tanaka K. et al. Concentration dependences of dielectric properties at 10(5) Hz and 10(6) Hz for aqueous solutions of hydroxypropyl cellulose // Liquid Crystals. 2007. Vol. 34, № 9. P. 1019–1028.

The concentration dependences of dielectric properties measured at 10(5) Hz and 10(6) Hz are reported for aqueous solutions of hydroxypropyl cellulose. Phase behaviour of the solutions was also observed with a polarizing optical microscope. For solutions with concentrations well above 40 wt%, polydomain textures, including the banded texture, were observed after a prehistory of deformation. No significant discontinuous changes in the dielectric constant, epsilon(r)', and loss factor, epsilon(r)'', were found at the concentrations around the onset of the isotropic cholesteric phase transition and in the biphasic region. In contrast, the steeper changes in epsilon(r)' and epsilon(r)'' were found at the critical concentration for the fully developed cholesteric phase transition with the polydomain textures.

49.U08248
Winter B., Faubel M. Photoemission from liquid aqueous solutions // Chem. Rev. 2006. Vol. 106, № 4. P. 1176–1211.

50.U17641
Yang L., Huang K., Yang X. Dielectric Properties of N,N-Dimethylformamide Aqueous Solutions in External Electromagnetic Fields by Molecular Dynamics Simulation // Journal of Physical Chemistry A. 2010. Vol. 114, № 2. P. 1185–1190.

Nonequilibrium molecular dynamics (NMD) simulations of the N, N-dimethylformamide (DMF) aqueous solution have been performed in the canonical ensemble (NVT) in both the absence and presence of external electromagnetic (E/M) field, using the SPC/E model for water and the optimized potentials for liquid simulations-all atom (OPLS-AA) model for DMF. The electromagnetic wave propagates in the z-axis direction with a frequency of 10 GHz, and the intensity of the electromagnetic field in the range 0 to 3 x 10(9) V/m is assumed in the simulation. The results indicate that as the intensity of the electromagnetic field increased, the dipole alignment of the DMF aqueous Solution molecules became more pronounced and the molecular polarizability gradually increased. In addition, the hydration number and the static dielectric constant of DMF aqueous Solutions decreased as the intensity of the electromagnetic field increased.

51.U60919
Yang X.-Q. et al. Molecular Dynamics Simulations and Experimental Measurements of Complex Permittivity of Aqueous Solutions of NaCl at Remote Sensing Frequencies // Russian Journal of Physical Chemistry A. 2013. Vol. 87, № 10. P. 1677–1683.

The dielectric properties of seawater are extremely important for ocean remote sensing at 5.1 and 13.6 GHz (frequencies that are commonly used by ocean remote sensing satellites). In this study, molecular dynamics simulations of aqueous sodium chloride solutions at mass concentrations between 1 and 10% and at the temperature ranges from 20 to 40 degrees C were investigated. Cole-Cole equation was used to describe the frequency-dependent complex permittivity. The simulated results were compared with experimental results at 5.1 and 13.6 GHz, and proved to approximatively agree with experimental results.

52.
Yoon G. Dielectric properties of glucose in bulk aqueous solutions: Influence of electrode polarization and modeling // Biosensors & Bioelectronics. 2011. Vol. 26, № 5. P. 2347–2353.

Impedance spectroscopy was applied to determine glucose concentration in the interstitial fluid for its potential use in diabetic monitoring. For this purpose, the changes in the measured dielectric properties due to the presence of glucose in water and saline solutions were examined between 40 Hz and 110 MHz. Electrode polarization (EP) was a dominant factor which shaped the spectrum at low frequencies. A theoretical model of EP using a constant phase-angle-element produced excellent matches to the measured data. By fitting the measured data to the model, the relative permittivity (epsilon(h)) and conductivity (sigma(l)) were obtained. For deionized water, the relative permittivity dropped from 80.1 to 73.2 and conductivity ranged between 0.142 and 0.212 mS/m when the glucose concentration was increased from 0 to 32 g/dl. For the same variation of glucose level in 0.15 M NaCl, epsilon(h) was reduced from 79.8 to 71.5 and sigma(l) decreased from 1.384 to 0.522 S/m. Glucose level produced a definite change in dielectric properties. However, the changes within the physiological range of glucose (less than a few hundred mg/dl) were small and appeared to be within the measurement error.

53.
Yueh S. et al. Aquarius geophysical model function and combined active passive algorithm for ocean surface salinity and wind retrieval // Journal of Geophysical Research-Oceans. 2014. Vol. 119, № 8. P. 5360–5379.

This paper describes the updated Combined Active-Passive (CAP) retrieval algorithm for simultaneous retrieval of surface salinity and wind from Aquarius' brightness temperature and radar backscatter. Unlike the algorithm developed by Remote Sensing Systems (RSS), implemented in the Aquarius Data Processing System (ADPS) to produce Aquarius standard products, the Jet Propulsion Laboratory's CAP algorithm does not require monthly climatology SSS maps for the salinity retrieval. Furthermore, the ADPS-RSS algorithm fully uses the National Center for Environmental Predictions (NCEP) wind for data correction, while the CAP algorithm uses the NCEP wind only as a constraint. The major updates to the CAP algorithm include the galactic reflection correction, Faraday rotation, Antenna Pattern Correction, and geophysical model functions of wind or wave impacts. Recognizing the limitation of geometric optics scattering, we improve the modeling of the reflection of galactic radiation; the results are better salinity accuracy and significantly reduced ascending-descending bias. We assess the accuracy of CAP's salinity by comparison with ARGO monthly gridded salinity products provided by the Asia-Pacific Data-Research Center (APDRC) and Japan Agency for Marine-Earth Science and Technology (JAMSTEC). The RMS differences between Aquarius CAP and APDRC's or JAMSTEC's ARGO salinities are less than 0.2 psu for most parts of the ocean, except for the regions in the Intertropical Convergence Zone, near the outflow of major rivers and at high latitudes.

54.
Zasetsky A.Y., Lyashchenko A.K., Lileev A.S. Ion-ion and ion-water aggregations and dielectric response of aqueous solutions of Li2SO4: molecular dynamic simulations study // Molecular Physics. 2011. Vol. 109, № 6. P. 813–822.

The dielectric properties of Li2SO4 aqueous solutions are studied using the method of molecular dynamic (MD) simulations. The dielectric response is computed for solutions with concentrations between 0.001 and 0.071 mole fraction of salt in the temperature range of 288 to 348 K. Computed values of the static dielectric constant and effective (weighted average) relaxation time are compared with available experimental data. The distributions of dielectric relaxation times are obtained by the decomposition of dipole moment autocorrelation functions (ACF) into a series of single exponentials in the time domain. The distributions of ion-ion and ion-water aggregations in concentrated solutions are computed and their connections to the low frequency modes observed in experimental dielectric spectra are examined. The nature of anomalous (different from single-exponential) dielectric relaxation in Li2SO4 aqueous solutions is discussed.

55.
Zuber A. et al. An empirical equation for the dielectric constant in aqueous and nonaqueous electrolyte mixtures // Fluid Phase Equilibria. 2014. Vol. 376. P. 116–123.

This work develops an empirical model to evaluate the dielectric constant of single or multi-solvents containing multiple ions, using only one adjustable parameter per ion. Correlations are performed for 35 salts in water, 9 in methanol, and 3 in ethanol. The dielectric constant of 9 two-solvent solutions (containing water, methanol, ethanol, 1-propanol, 2-propanol, or acetone) is predicted. In addition, predictions of the dielectric constant of a mixture containing water, methanol, and NaCl are presented. Besides the specific parameter for each ion, a general parameter for cations and another for anions, specific to the each solvent, are obtained. They are recommended for calculating the dielectric constant in solutions whose experimental data are unavailable in the literature.

56.005733
Андреев Г. А., Станкевич О. К. Вариации радиояркостных температур облачной атмосферы, водной поверхности и почвогрунтов в сантиметровом и миллиметровом диапазонах длин волн // Радиотехника и электроника. 2002. Т. 47. № 7. С. 814-821

Предложены и экспериментально апробированы методики оценок вариаций радиояркостных температур облачной атмосферы, водной поверхности и почвогрунтов на длинах волн 8 х10-3 м и13, 5 х10-3 м. Показано, что измерение температурных контрастов на водной поверхности в миллиметровом диапазоне возможно только при температурах выше 50 °С, а на волнах сантиметрового диапазона в любом интервале положительных температур от 0 до 70 °С

57.002523
Артемьев В.В., Белов Н.П. и др. Контроль оптических свойств водных растворов карбамида с применением промышленной рефрактометрии // Известия высших учебных заведений. Приборостроение. 2015. Т. 58. № 6. С. 473-477.

Проведены измерения концентрационной и температурной зависимостей показателя преломления n(m d,t) водных растворов карбамида, а также его температурного коэффициента dn/dt. Дано краткое описание промышленного рефрактометра для контроля концентрации водных растворов карбамида в технологическом потоке и программных методов его настройки и калибровки. Приведены интерполяционные выражения для показателя преломления и его температурного коэффициента. Представлены результаты численного моделирования спектров коротковолнового поглощения.

58.
Беляева Т.А., Бобров П.П., Кондратьева О.В. Изменение диэлектрических свойств связанной воды в почвах при увеличении ее количества // Вестник Сибирского Государственного Аэрокосмического Университета им. академика М.Ф. Решетнева. 2013. № 5 (51). С. 92-95.

Выполнены измерения комплексной диэлектрической проницаемости (КДП) малоувлажненных почв в диапазоне частот 1 МГц — 4 ГГц. Показано, что КДП связанной воды на частотах ниже 1—1,5 ГГц зависит от ее количества в почве. Создана модель зависимости КДП от частоты и влажности, включающая три частотные области релаксации. Показано, что учет зависимости КДП связанной воды от ее количества позволяет существенно повысить точность рефракционной модели почв при малых влажностях. Обнаружено, что в почвах с большим содержанием глины на частотах ниже 20 МГц наблюдаются отклонения от монотонности в зависимости КДП связанной воды от влажности. Полученные результаты могут быть использованы для повышения точности дистанционного определения влажности малоувлажненных почв микроволновыми методами.

59.005733
Брискина Ч.М., Гайдук В.И., Цейтлин Б.М. Диэлектрический отклик в субмиллиметровом и дальнем ИК-диапазонах, обусловленный упругими взаимодействиями в жидкой воде // Радиотехника и электроника. 2004. Т. 49. № 7. С. 790-800.

На основе предложенной авторами структурно-динамической модели димера молекул воды составлено уравнение одномерного движения, описывающего вращательные качания молекулы воды под действием упругих сил водородной связи. Найдены средние значения амплитуды и частоты вращательных качаний и их статистические распределения. Предложена двухфракционная модель воды, позволяющая рассчитать на основе аналитической теории спектры комплексной проницаемости и поглощения воды в полосе 0...1000 см -1. Предполагается, что фракция H-связанных молекул воды -вибронов сосуществуют с фракцией либраторов - молекул, совершающих более свободные вращательные качания. Показано, что первая фракция обусловливает полосу поглощения в области 200 см -1 и определяет специфику субмиллиметрового спектра диэлектрических потерь. Вторая фракция ответственна за низкочастотный (релаксационный) спектр и основную (либрационную) полосу поглощения воды в дальней инфракрасной области спектра.

60.001573
Волков А.А., Артемов В.Г., Пронин А.В. О происхождении диэлектрических свойств воды // Доклады Академии Наук. 2014. Т. 455. № 1. С. 26-29.

61.005127
Григорук В.И., Понежа Г.В., Понежа С.Г. Голографическая интерферометрия жидкостей на длине волны гелий-неонового лазера при микроволновом облучении // Оптика и спектроскопия. 2008. Т. 104. № 6. С. 1033-1039.

С помощью дифференциального голографического интерферометра исследованы изменения оптического показателя преломления ряда органических жидкостей, воды и некоторых биологических водных растворов при воздействии на них электромагнитного излучения в диапазоне частот 37.578 ГГц. Установлено, что облучение интенсивностью до 10 мВт/см2 может вызвать в жидкостях уменьшение показателя преломления 10-3, что является следствием тепловых изменений диэлектрической постоянной исследуемого вещества. Величина и динамика изменений показателя преломления определяются интенсивностью облучения и физическими параметрами жидкостей (дипольным моментом молекул, коэффициентом поглощения, диэлектрической проницаемостью и температурным коэффициентом показателя преломления) и в пределах погрешности измерений не зависят от взаимной ориентации ортов поляризации микроволнового и оптического полей.

62.009058
Еремеев В.А. К вопросу создания консистентных баз данных радиояркостных температур с различных спутниковых систем для изучения вариабельности геофизических параметров ледового покрова Арктики // Исследование Земли из космоса. 2003. № 2. С. 59-72.

Для исследования геофизических параметров ледового покрова Арктики на длительном интервале времени требуется наличие их консистентного набора, полученного из данных различных измерителей. Радиояркостные температуры с американских микроволновых радиометров SMMR и SSM/I на спутниках "Nimbus-7" и DMSP F8, Fll, F13 - один из основных источников данных для глобальных исследований Арктики. Для устранения неоднородностей в наборе радиояркостных температур, связанных с различиями в параметрах спутников и сенсоров, их обычно необходимо преобразовать к базису одного радиометра с использованием уравнений линейной регрессии, определенных на синхронных измерениях с разных спутников. В работе исследованы коэффициенты линейной регрессии, устанавливающие соотношения между каждой парой последовательно функционировавших сенсоров для каналов Tb(18/19v), Tb(18/19h), Tb(37v) и Tb(37h). Определено влияние сокращения объема данных радиояркостных температур SSM/I F11 на коэффициенты линейной регрессии, связывающие показания SSM/I F11 и F13. Корреляция данных этих двух сенсоров при сокращении периода пересечения меняется слабо. Проанализированы коэффициенты линейной регрессии, полученные для каждой пары синхронных среднесуточных изображений с разных сенсоров в периоды совместного функционирования спутников. Выявлены тренды этих коэффициентов, определены уровни значимости. Исследованы разности радиояркостных температур каналов Tb(19h) и Tb(37h). Показано, что линейная комбинация радиояркостных температур менее чувствительна к преобразованиям от базиса одного сенсора к базису другого, чем исходные измерения. Таким образом, для упрощения анализа геофизических параметров ледового покрова целесообразно предварительно вычислить их по исходным измерениям с различных сенсоров с последующим объединением в консистентную базу данных.

63.007777
Ершов Б.Г., Яната Э. и др. Исследование методом импульсного радиолиза реакций гидратированного электрона и гидроксильного радикала с оксалат-ионом в нейтральном водном растворе // Химия высоких энергий. 2008. Т. 42. № 1. С. 5-10.

Методом импульсного радиолиза измерены константы скорости реакций и радикала OH. c оксалат-ионом в нейтральном водном растворе. Они равны (3.5 ± 0.5) ? 107 M-1 с-1 и (1.5 ± 0.2) ? 107 M-1 с-1 соответственно. Возникающий в реакции с анион-радикал -OOC C.OO2 характеризуется в оптическом спектре полосой поглощения с максимумом при 270 нм и коэффициентом экстинкции (2400 ± ± 200) л моль-1 см-1. Анион-радикал .OOC COO-, продукт реакции с радикалом OH., имеет возрастающее по интенсивности в УФ-область поглощение без максимума ( 220 = 1800 л моль-1 см-1). Обсужден механизм радиационно-химических превращений водных растворов оксалат-ионов.

64.010534
Казаринов К.Д. Определение диэлектрических характеристик водных растворов и суспензий клеток с помощью волноводно-диэлектрического резонатора // Электронная техника. Серия 1: СВЧ-техника. 2007. № 5 (493). С. 31-38.

Предлагается методика определения диэлектрических характеристик водных растворов и суспензий, основанная на температурной зависимости коэффициента поглощения водных растворов, с помощью одной из модификаций волноводно-диэлектрического резонатора.

65.006952
Кедик С.А., Вагина А.А. и др. Влияние различных факторов на коэффициент поглощения водных растворов сополимеров N-винилпирролидона с 2-метил-5-винилпиридином // Химико-фармацевтический журнал. 2015. Т. 49. № 6. С. 47-50.

Проведено спектрофотометрическое исследование водных растворов 3 образцов сополимеров N-винилпирролидона с 2-метил-5-винилпиридином с различным соотношением звеньев мономеров. Получены концентрационные зависимости оптической плотности растворов при 269 нм и рассчитаны удельные коэффициенты поглощения этими растворами. Найдены области значений рН и температур с наиболее стабильными результатами определений. Полученные результаты могут быть положены в основу разработки методики количественного определения сополимеров N-винилпирролидона с 2-метил-5-винилпиридином в водных растворах.

66.001681
Кобелев А.В., Лилеев А.С., Лященко А.К. Температурная зависимость СВЧ-диэлектрических свойств водных растворов иодида калия // Журнал неорганической химии. 2011. Т. 56. № 4. С. 697-704.

Изучена комплексная диэлектрическая проницаемость водных растворов KI в интервале концентраций 0.50-4.01 m при температурах 288-323 К в области дисперсии диэлектрической проницаемости воды. Измерения высокочастотной диэлектрической проницаемости ( ) и потерь ( ) выполнены на семи частотах в интервале 7.5-25 ГГц. Измерена низкочастотная электропроводность указанных растворов, необходимая для расчета ионных потерь. В растворах наблюдается одна область релаксации, описываемая уравнениями Дебая или Коула-Коула с малыми параметрами распределения. Изучены температурные и концентрационные зависимости статической диэлектрической проницаемости и времени диэлектрической релаксации, рассчитана энтальпия активации процесса диэлектрической релаксации. Обнаружено, что в растворах высокой концентрации исчезает температурная зависимость статической диэлектрической проницаемости. Подтверждается эффект нарушения структуры воды ионами K+ и I-, который исчезает при переходе к повышенным температурам.

67.002519
Ковалева Л.А., Миннигалимов Р.З., Зиннатуллин Р.Р. Исследование устойчивости водонефтяной эмульсии в электромагнитном поле в зависимости от её диэлектрических свойств // Известия высших учебных заведений. Нефть и газ. 2010. № 2. С. 59-62.

Рассматривается проблема обезвоживания водонефтяных эмульсий и возможность применения электромагнитного поля высокой частоты. Приводятся результаты экспериментальных исследований диэлектрических характеристик образцов водонефтяной эмульсии. Определена степень разрушения эмульсии при высокочастотном электромагнитном воздействии в зависимости от ее диэлектрических параметров. Ил.5, библиогр.6 назв.

68.001681
Лилеев А.С., Логинова Д.В., Лященко А.К. СВЧ-диэлектрические свойства водных растворов гидроксида калия // Журнал неорганической химии. 2011. Т. 56. № 6. С. 1017-1023.

Изучены высокочастотные диэлектрические свойства водных растворов гидроксида калия на частотах 13-25 ГГц в широкой области концентраций в интервале температур 288-308 К. С иcпользованием экспериментальных данных по электропроводности определены ионные потери на высоких частотах. Рассчитаны статическая диэлектрическая проницаемость (?s), время (?) и термодинамические параметры активации ( ?H?++ , ?G?++ , ?S?++ ) процесса диэлектрической релаксации. Эти величины уменьшаются при переходе от воды к раствору. Тем самым показано нарушающее воздействие гидроксида калия на исходную сетку водородных связей воды.

69.001681
Лященко А.К., Балакаева И.В., Тимофеева Л.М. и др. СВЧ диэлектрическая проницаемость и релаксация водных растворов трифторацетата калия // Журнал неорганической химии. 2013. Т. 58. № 7. С. 988-993.

Представлены результаты измерения СВЧ диэлектрических свойств водных растворов трифторацетата калия на семи частотах (7.5-25 ГГц) при температурах 288, 298, 308 К. Рассчитаны статические диэлектрические константы, времена и активационные параметры процесса диэлектрической релаксации. Показаны молекулярно-кинетическая стабилизация и увеличение степени связанности и структурированности сетки Н-связей воды в растворах трифторацетата калия, сходные с изменениями воды в растворах ацетата калия. Они связаны с гидрофобной гидратацией иона трифторацетата, которая впервые установлена методом СВЧ диэлектрической спектроскопии и определяется влиянием его малополярной CF3-группы.

70.001573
Лященко А.К., Каратаева И.М. и др. Радиояркостные контрасты и излучение водных растворов солей в миллиметровой области спектра // Доклады Академии Наук. 2015. Т. 462. № 5. С. 561-564.

71.039689
Никулин Р.Н. и др. Оценка потерь энергии электромагнитной волны в биологических средах // Биомедицинская радиоэлектроника. 2010. № 6. С. 12-15.

Исследована частотная зависимость потерь энергии электромагнитной волны при падении ее на биологическую среду. Показано, в частности, что величины диэлектрических потерь в СВЧ-диапазоне, определенные экспериментально и обусловленные наличием мнимой части диэлектрической проницаемости, находятся в хорошем соответствии с аналогичными величинами, вычисленными согласно соотношений Дебая при условии, что время релаксации составляет величину порядка 6,4?10-11 с.

72.002574
Новиков И.В. и др. Влияние 4-аминобензонитрила на диэлектрические и оптические свойства жидкокристаллической смеси ЖК-807 // Известия высших учебных заведений. Серия: Химия и химическая технология. 2011. Т. 54. № 3. С. 102-104.

Получены температурные и концентрационные зависимости статической ди-электрической проницаемости и показатели преломления жидкокристаллических растворов 4-аминобензонитрила в мезоморфной смеси ЖК-807. Показано, что введение полярного немезогена сопровождается увеличением диэлектрической анизотропии, свя-занной с образованием Н-комплексов мезоген-немезоген.

73.
Одинаев С., Махмадбегов Р.С. Исследование диэлектрических свойств водного раствора хлорида лития в зависимости от параметров состояния // Доклады Академии Наук Республики Таджикистан. 2014. Т. 57. № 9-10. С. 746-754.

Исследованы частотные спектры коэффициентов диэлектрической проницаемости и диэлектрических потерь водного раствора LiCl в зависимости от плотности, концентрации и температур. При определенном выборе потенциальной энергии взаимодействия между структурными единицами раствора и радиальной функции распределения проведены численные расчеты коэффициентов трения, а также времен релаксации в импульсном, и конфигурационном, пространстве. С учётом полученных численных данных этих параметров произведены численные расчёты и для водного раствора хлорида лития для четырех концентраций, интервал температур от 283К до 353К и диапазон частот от 3 ГГц до 7.4?10 3 ГГц.

74.002538
Паршин В.В., Серов Е.А. Резонансный метод исследования диэлектрических жидкостей в миллиметровом и субмиллиметровом диапазонах длин волн // Известия высших учебных заведений. Радиофизика. 2011. Т. 54. № 8-9. С. 701-707.

Рассматривается модификация резонаторного «безкюветного» метода измерения показателя преломления и поглощения жидких диэлектриков, при которой не требуется привлечения априорной информации о толщине слоя жидкости. Приведены результаты прецизионных измерений величин показателя преломления и тангенса угла потерь современных жидких диэлектриков в миллиметровом и субмиллиметровом диапазонах. Данные материалы предполагается использовать как для охлаждения элементов мощных гиротронов (с выходной мощностью порядка мегаватта в непрерывном режиме), в которых эти жидкости непосредственно взаимодействуют с электромагнитным излучением, так и для поглощения микроволновой энергии в различного рода калориметрических измерительных нагрузках и оконечных нагрузках, поглощающих всю излучённую мощность.

75.039689
Пенской А.С., Шеин А.Г. Изучение диэлектрических свойств воды в СВЧ-диапазоне // Биомедицинская радиоэлектроника. 2011. № 9. С. 62-66.

Получены экспериментальные зависимости коэффициентов отражения и затухания электромагнитных волн в водных средах от частоты падающего излучения. Данные результаты сопоставлены с теоретически рассчитанными, с учетом модели, установленной Дебаем для разбавленных растворов диполей в жидкостях и твердых телах.

76.005733
Романов А.Н. Влияние массовой концентрации минеральных солей на диэлектрические характеристики их водных растворов в микроволновом диапазоне // Радиотехника и электроника. 2004. 49. № 10. С. 1235-1242.

Исследовано влияние массовой концентрации солей на комплексный показатель преломления и комплексную диэлектрическую проницаемость водных растворов солей Na 2CO 3 и NaCl. Показано, что для описания комплексной диэлектрической проницаемости может быть использована рефракционная модель, в которой водный раствор представлен как многофазная система, состоящая из чистого растворителя, не взаимодействующего с ионами растворенных солей, и объемов воды, заключенных в дальней и ближней гидратных оболочках, образующихся вокруг катиона и аниона. На этой основе предложен метод определения массовой концентрации соли в водном растворе по измеренной диэлектрической проницаемости.

77.01140X
Романов А.Н., Суковатова А.Ю., Рапута В.Ф. Моделирование диэлектрических свойств снеговой воды с малой концентрацией растворенных веществ // Оптика атмосферы и океана. 2013. Т. 26. № 7. С. 601-603.

Установлены зависимости диэлектрических характеристик снеговой воды от загрязняющих веществ, собравшихся в снеговом покрове за весь период снегонакопления. Приведены результаты расчета диэлектрических свойств с учетом накопившихся химических веществ. Предложена методика, характеризующая влияние накопившихся в снеговом покрове веществ на диэлектрические свойства снеговой воды с использованием регрессионного анализа.

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Суковатова А.Ю., Романов А.Н., Оскорбин Н.М. Моделирование диэлектрических свойств воды из природных минерализованных водоемов с использованием регрессионного анализа // Оптика атмосферы и океана. 2011. Т. 24. № 11. С. 1007-1008.

Установлены зависимости диэлектрических параметров воды из соленых и горько-соленых озер равнинной части Алтайского края от совокупности химических показателей. Приведены результаты расчета диэлектрических свойств с учетом растворенных в воде химических веществ. Предложена методика учета влияния растворенных в воде химических веществ на диэлектрические свойства с использованием регрессивного анализа.

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Сухонин, Е. В. Аналитические модели для расчета радиояркостной температуры излучения дождя в миллиметровом и сантиметровом диапазонах радиоволн // Радиотехника и электроника. 2007. Т. 52. № 1. С. 24-27.

Предложены и разработаны три аналитические модели для расчета радиояркостной температуры Tя излучения дождя в миллиметровом и сантиметровом диапазонах радиоволн. Обоснован выбор необходимой для расчета Tя модели излучения системы атмосфера с осадками ? земная поверхность на основе анализа различных физических процессов, влияющих на это излучение. Данные процессы включают в себя поглощение и рассеяние излучения гидрометеорами, а также собственное излучение и отражение радиоволн земной поверхностью.

80.004336
Федосеева Е.В. Оценка погрешности измерений радиояркостной температуры в радиотеплолокационных системах контроля метеопараметров с компенсацией фоновых шумов // Метрология. 2014. № 11. P. 33–42.

Рассмотрены принципы оценки погрешностей измерений радиояркостной температуры при компенсации действия фоновых шумов в радиотеплолокационных системах контроля метеопараметров. Сигнал компенсации формируется на выходе дополнительного канала антенны со специальной формой диаграммы направленности. Представлены результаты оценки данной погрешности при использовании двухканальной двухмодовой антенны в радиотеплолокационной системе.

81.005733
Цейтлин Б.М., Гайдук В.И., Никитов С.А. Диэлектрический отклик на упругие трансляции и переориентации водородно-связанных молекул льда и воды // Радиотехника и электроника. 2005. Т. 50. № 9. С. 1085-1106.

Аналитически в виде двух взаимосвязанных линий Лорентца описан диэлектрический отклик на упругие поворотные вибрации Н-связанных полярных молекул и на трансляционные вибрации образующихся на них зарядов. Рассмотрено влияние величин поворотной и продольной силовых констант Н-связи на спектры комплексной диэлектрической проницаемости (ДП) и поглощения. Показано, что диэлектрический отклик на упругие вибрации водородно-связанных молекул наблюдается в дальнем инфракрасном диапазоне: колебания зарядов по линии Н-связи обусловливают трансляционную полосу в области 200 см-1, а угловые смещения диполей - расположенную рядом V-полосу в области 150 см-1. В рамках модели шляпного потенциала дано описание либрационной полосы, расположенной у границы инфракрасного диапазона. Разработанная модель применена также для расчета широкополосного спектра ДП воды, включая релаксационный (дебаевский) спектр. Показано, что расчетные спектры ДП и поглощения во льду и в воде удовлетворительно согласуются с экспериментальными для температур -7 и, соответственно, 27°С.

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