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Thermodynamic data on the properties of the water-based electrolyte systems are very valuable for fundamental physical chemistry and for industrial applications. The missing data both on the dilution and dissolution enthalpies for the ternary CsCl−MgCl2−H2O mixed electrolyte system were investigated by means of the calorimetry method. The dilution calorimetry was performed at 298 K for the set of solutions from diluted to concentrated at constant ratio Cs+/Mg2+=1.8. The relative partial molar enthalpies, ideal, total, and excess ones were calculated. By means of the dissolution calorimetry, the standard enthalpies of formation, the enthalpies, and entropies for the double salt formation from simple salts were evaluated. The results obtained indicate that entropy as the major factor affecting the formation of the joint compound, both in the liquid and solid phases. These data can be implemented in thermodynamic databases and allow for accurate thermodynamic calculations for the salts extraction from natural water sources and for its possible application as thermochemical energy storage.

The influence of ionic interactions in ternary aqueous and aqueous-organic solutions of metal halides on the structure of the solid phases in equilibrium with the solutions is analyzed. An original classification of double and complex salts, reflecting the peculiarities of their structure, is given. The conditions for the formation of various types of these compounds are determined. The factors that determine the preservation of the metal ion surrounding during the solution-solid phase transition are revealed.

In the current paper, in situ laser-induced synthesis of gas sensing microcomposites based on molybdenum and its oxides is discussed. The influence of pH of the solutions used for deposition and optical characteristics of a dielectric substrate on electrical conductivity and sensor properties of the synthesized microdeposits is also studied. It was shown that the phase distribution in the obtained materials is consistent with temperature level in the thermal zones of the laser beam focused on the surface of a dielectric substrate of different type. In turn, highly developed surface area of these microsensors is directly responsible for their high sensitivity, short response time, and low temperature of regeneration with respect to hydrogen sulfide and ammonia. Indeed, the highest sensitivity was observed for detection of small concentration (≤50 ppm) of hydrogen sulfide at temperatures of 300–350 °C, whereas at temperatures of 300 °C or less, the deposited molybdenum-containing microstructures are applicable for the ammonia sensing. Thus, this work demonstrates that the method of laser-induced metal deposition is a promising and perspective approach for fabrication of new effective standalone micro-sized gas sensors.

The main purpose of this study was to investigate the local structure and dynamics in 'water-in-salt' solutions, namely the ternary concentrated LiCl-CsCl-D2O electrolytes. Water based electrolyte solutions are components of natural waters, they are very widespread and possess many practical abilities. NMR was applied as the main technique to study the local structure of the solutions as well as ion and solvent dynamics. The characteristic reorientation times (τc) were calculated from spin-lattice relaxation times for 2H, 7Li, and 133Cs nuclei. The diffusion coefficients (D) for 1H, 7Li, and 133Cs nuclei were also obtained. We have confirmed that most of the molecules and ions are combined into dynamic clusters, 'cybotactic groups', with lifetimes long enough for them to diffuse as a whole unit. Thus, the results provide direct experimental confirmation of the existence of 'cybotactic groups' predicted earlier for concentrated electrolyte solutions. The precise self-diffusion coefficients show the state of ions in the system and can be used as a reference for modelling of such systems.

Enthalpies of dissolution of the binary salt LiCl·3CsCl·4H2O and dry mixtures of lithium and cesium chlorides in the molar ratio 1: 3 were measured by the calorimetry method. The value of the mutual influence of ions in solution was determined, and the enthalpy of the binary salt formation from the individual components was calculated.

Local molybdenum deposit obtainment is promising for micro thermocouples creation on dielectric surfaces. This paper is dedicated to development of method of laser-induced molybdenum deposition from water-based solution of inorganic salt on Sitall st-50 and glass dielectric substrates, as well as research of solution composition, pH and substrate optical properties influence on result of laser-induced molybdenum deposition from solution. It was shown that depending on dielectric substrate type, as a result of laser-induced deposition metallic molybdenum or molybdenum dioxide deposit forms: molybdenum dioxide deposits in case of optically clear substrate and metallic molybdenum deposits in case of opaque glass-ceramics. While modelling interim case via using clouded glass, mixture of molybdenum and its oxide was successfully obtained.