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A cadmium tungstate crystal scintillator enriched in 106 Cd was developed for an experiment to search for double beta processes in 106 Cd. With this aim samples of cadmium with natural isotopic composition and enriched in 106 Cd were purified by vacuum distillation. Cadmium tungstate compounds were synthesized from solutions. The absolute isotopic composition of the enriched cadmium was accurately determined as 66.4% by thermal ionisation mass-spectrometry. A 106 CdWO 4 crystal boule was grown by the low-thermal-gradient Czochralski technique. The total irrecoverable loss of the enriched cadmium in all the stages of the crystal scintillator production does not exceed 2.3%. The produced 106 CdWO 4 crystal scintillator with mass of 216 g exhibits good optical and scintillation properties.

A process has been developed for the preparation of extrapure WO suitable for crystal growth. The method involves thermal decomposition of ammonium paratungstate (APT) powder at 230–250° C, resulting in the formation of soluble ammonium metatungstate (AMT). The AMT solution is then purified and hydrolyzed. The resultant purified APT is converted to WO3. The reaction yield is at a level of 95%. The contents of metallic impurities, especially those of polyvalent impurities (Fe, Mn, Cu, Pb, V, Cr, and others), capable of influencing the optical properties of crystals, was comparable to their detection limit: 10−6 to 10−5 wt %. The purification process was tested using a pilot-scale system. The purity was confirmed by the synthesis of high-quality CdWO4 crystals.

The enthalpies and temperatures of melting of RSi(CH3)3, R4Si, R3P, R3As, R3Sb, R3Bi, R2Te and R2Hg (R=C6F5) were obtained by scanning calorimetry measurements. The pressure of the saturated and unsaturated vapors of RSi(CH3)3, R2Si(CH3)2, R4Si, R3Ga, R3P, R3As, R3Sb, R3Bi, R2Te and R2Hg has been measured by the static method with a membrane-gauge manometer. It was established that all investigated substances proceeded to vapor as monomers. Equations approximating the dependences of saturated vapor pressures on temperature and the enthalpies and entropies of vaporization were obtained. Grafite films with silicon intercalated up to 25 at.% were grown by CVD using R4Si as a precursor. These films showed semiconductor properties in the temperature interval 80–300 K.

Two ionic clathrate hydrates with different structures are formed in the binary system tetrabutylammonium fluoride–water, namely tetragonal structure-I hydrate (TS-I) (n-С4H9)4NF · 32.8H2O, and cubic superstructure-I hydrate (CSS-I) (n-С4H9)4NF · 29.7H2O. The heats of fusion (ΔHf) of these polyhydrates were measured calorimetrically with differential scanning calorimeter. For TS-I polyhydrate ΔHf = (204.8 ± 2.3) kJ/mol hydrate, for CSS-I hydrate ΔHf = (177.5 ± 3.1) kJ/mol polyhydrate. The change of water molecules energy state in the water lattices of TS-I and CSS-I polyhydrates are discussed.

The unsaturated and saturated pressures of gallium trichloride vapor were measured by the static method with membrane-gauge manometers in wide pressure (0.2–760 Torr) and temperature (313–1071 K) intervals. Scanning calorimetry was used to determine the thermodynamic characteristics of GaCl3 fusion. The thermodynamic characteristics were obtained for sublimation, fusion, vaporization, and association in the vapor of GaCl3 molecules. The enthalpies of formation and the absolute entropies of GaCl3 in the liquid and gaseous phases and Ga2Cl6 in the gaseous phase were calculated using literature data.

Energy resolution, light yield, non-proportionality in the scintillation response, alpha/beta ratio, pulse shape for gamma rays and alpha particles were studied with CdWO4 crystal scintillators. Some indication for a difference in the emission spectra for gamma rays and alpha particles was observed. No dependence of CdWO4 pulse shape on emission spectrum wavelengths under laser, alpha particles and gamma ray excitation was observed. Dependence of scintillation pulse shape for gamma quanta and alpha particles and pulse-shape discrimination ability on temperature was measured in the range of 0-24 degrees., Comment: 22 pages, 14 figures, submitted to NIMA

The temperature dependence of the heat capacity of germanium dibromide was studied over the temperature range 8.3–314 K by adiabatic calorimetry. The enthalpy of formation of solid germanium dibromide was determined by solution calorimetry. Scanning calorimetry was used to obtain the thermodynamic characteristics of fusion of GeBr2. The thermodynamic characteristics of the Ge-Br system studied by us earlier were used to consistently calculate the consistent standard enthalpies of formation and absolute entropies of germanium bromides in the solid, liquid, and gaseous states.

The enthalpies of fusion of C6H5SiH3, C6F5Si(CH3)3, and (C6H5)4Si were obtained in scanning calorimetry measurements. Pressure over the condensed talylsilane 4-CF3C6F4SiCH3, phenylsilane C6H5SiH3, and pentafluorophenylsilane C6F5SiCH3, (C6F5)2Si(CH3)2, and (C6F5)4Si phases was measured by the static method with the use of membrane null manometers. Equations approximating the dependences of saturated vapor pressures on temperature and the enthalpy and entropy of vaporization were obtained.

The syntheses of high purity GeI 2 and GeI 4 from the elements are described. The vapour pressure over solid germanium (II) iodide has been measured by the static method with a membrane-gauge manometer from T =550 K to T =650 K and the molar enthalpy and entropy of sublimation calculated by second-law and third-law methods. Enthalpy differences for solid and liquid GeI 2 were measured in the temperature interval (330 to 770) K by drop calorimetry. The temperature, enthalpy and entropy of melting of germanium (II) iodide were determined. The values of the standard molar thermodynamic properties for solid and liquid GeI 2 are presented from T =298.15 K to T =781 K. We have used the maximum likelihood method in the treatment of the data obtained together with previous reported values. On the basis of this work we recommend a set of standard enthalpies of formation and absolute entropies for the Ge–I compounds.

The thermochemical and structural aspects of the occurrence of two anomalies in the temperature dependence of the specific heat of YBa2Cu3O6.91 are considered. The anomalies were found at T = 300–500 K and T > 600 K. The specific heat was measured by mixing calorimetry in the temperature range 300–900 K. Analytical expressions for the temperature dependences of enthalpy and specific heat were obtained. The observed anomalies were confirmed by structural data and measurements of the temperature dependence of the linear‐expansion coefficient. The appearance of the anomalies is explained by the presence of apical oxygen.

A cadmium tungstate crystal boule enriched in $^{116}$Cd to 82% with mass of 1868 g was grown by the low-thermal-gradient Czochralski technique. The isotopic composition of cadmium and the trace contamination of the crystal were estimated by High Resolution Inductively Coupled Plasma Mass-Spectrometry. The crystal scintillators produced from the boule were subjected to characterization that included measurements of transmittance and energy resolution. A low background scintillation detector with two $^{116}$CdWO$_4$ crystal scintillators (586 g and 589 g) was developed. The detector was running over 1727 h deep underground at the Gran Sasso National Laboratories of the INFN (Italy), which allowed to estimate the radioactive contamination of the enriched crystal scintillators. The radiopurity of a third $^{116}$CdWO$_4$ sample (326 g) was tested with the help of ultra-low background high purity germanium $\gamma$ detector. Monte Carlo simulations of double $\beta$ processes in $^{116}$Cd were used to estimate the sensitivity of an experiment to search for double $\beta$ decay of $^{116}$Cd., Comment: 24 pages, 13 figures, 3 tables, accepted for publication on Journal of Instrumentation

Standard enthalpies of formation for solid solutions of composition Nd1 + x Ba2 − x Cu3O y (x = 0–0.8, y = 6.65–7.24) from oxides were determined by solution calorimetry. The heat capacity of NdBa2Cu3O6.87 phase was measured in the range 5–320 K by low-temperature adiabatic calorimetry. The absolute entropy S o(T), the difference of enthalpies H o(T)-H o(0 K), and the reduced Gibbs energy Φo(T) = S o(T)–[H o(T)–H o(0)]/T were calculated on the basis of smoothed dependence C p (T) in the 0–320 K range. An assessment was made for the heat capacities and the absolute entropies of solid solutions Nd1+x Ba2−x Cu3O y . The obtained set of thermodynamic parameters can be used for the calculation of phase equilibria in the Nd-Ba-Cu-O system.

The thermodynamic analysis of the niobium CVD in Nb-Hal-(H)-inert gas (Hal = I, Cl) systems has been performed with using the method of minimization of the Gibbs' free energy for the wide region of conditions. The results of the thermodynamic calculations allow to select the Nb-I-inert gas system as the more preferable hydrogen free system. The experimental niobium CVD data in the Nb-Cl-H-inert gas system were analyzed with thermodynamic view. The calculations and experimental results show a good agreement.

The standard molar enthalpy of formation of SrY 0.05 Ce 0.95 O 2.975 has been derived by combining the enthalpy of solution in 1 M HCl + 0.1 KI with auxiliary literature data, Δ f H ° (SrY 0.05 Ce 0.95 O 2.975 , s, 298.15 K) = −1720.4 ± 3.4 kJ/mol. The formation enthalpy of SrY 0.05 Ce 0.95 O 2.975 from the mixture of binary oxides is Δ ox H ° (298.15 K) = −45.9 ± 3.4 kJ/mol and the enthalpy of reaction of SrY 0.05 Ce 0.95 O 2.975 with water forming Sr(OH) 2 , CeO 2 , and Y 2 O 3 is Δ r H ° (298.15 K) = −85.5 ± 3.4 kJ/mol. Our data and the entropies of different substances show that SrY 0.05 Ce 0.95 O 2.975 is thermodynamically stable with respect to a mixture of SrO, Y 2 O 3 , CeO 2 and that the reaction of SrY 0.05 Ce 0.95 O 2.975 with water is thermodynamically favourable.

The heat capacity of two samples of BaCuO 2 was measured in a vacuum adiabatic calorimeter in the temperature range 8–305 K. The thermodynamic functions of barium cuprate (entropy, enthalpy, Gibbs free energy) were calculated on the basis of C p - T dependences. Both samples exhibited an anomalous rise in C p at low temperatures (below 12 K). Our data are compared with previously measured data.

In heat capacity of YBa2Cu3O6.9 the anomaly has been extracted in the range 250–600 K with maximum at ∼470 K. This anomaly has been shown to correspond to the II kind phase transition from the phase with low mobility of oxygen atoms O1 to the phase with high mobility. At T>600 K the indication of another anomaly has been discovered, probably of ortho-tetra phase transition. Also, the different behavior of resistance ρ(T) at fast and slow heating has been discovered. Such behavior revealed itself in region of the II kind phase transition. Apparently, it was caused by the oxygen subsystem reorganization.

A search for double $\ensuremath{\beta}$ processes in ${}^{106}$Cd was carried out at the Gran Sasso National Laboratories of the INFN (Italy) with the help of a ${}^{106}$CdWO${}_{4}$ crystal scintillator (215 g) enriched in ${}^{106}$Cd up to 66$%$. After 6590 h of data taking, new improved half-life limits on the double $\ensuremath{\beta}$ decay processes in ${}^{106}$Cd were established at the level of ${10}^{19}$--${10}^{21}$ yr; in particular, ${T}_{1/2}^{2\ensuremath{\nu}\ensuremath{\varepsilon}{\ensuremath{\beta}}^{+}}\ensuremath{\geqslant}2.1\ifmmode\times\else\texttimes\fi{}{10}^{20}$ yr, ${T}_{1/2}^{2\ensuremath{\nu}2{\ensuremath{\beta}}^{+}}\ensuremath{\geqslant}4.3\ifmmode\times\else\texttimes\fi{}{10}^{20}$ yr, and ${T}_{1/2}^{0\ensuremath{\nu}2\ensuremath{\varepsilon}}\ensuremath{\geqslant}1.0\ifmmode\times\else\texttimes\fi{}{10}^{21}$ yr. The resonant neutrinoless double-electron captures to the 2718-, 2741-, and 2748-keV excited states of ${}^{106}$Pd are restricted to ${T}_{1/2}^{0\ensuremath{\nu}2K}\ensuremath{\geqslant}4.3\ifmmode\times\else\texttimes\fi{}{10}^{20}$ yr, ${T}_{1/2}^{0\ensuremath{\nu}K{L}_{1}}\ensuremath{\geqslant}9.5\ifmmode\times\else\texttimes\fi{}{10}^{20}$ yr, and ${T}_{1/2}^{0\ensuremath{\nu}K{L}_{3}}\ensuremath{\geqslant}4.3\ifmmode\times\else\texttimes\fi{}{10}^{20}$ yr, respectively (all limits at 90$%$ confidence level). A possible resonant enhancement of the $0\ensuremath{\nu}2\ensuremath{\varepsilon}$ processes is estimated in the framework of the quasiparticle random phase approximation (QRPA) approach. Radioactive contamination of the ${}^{106}$CdWO${}_{4}$ crystal scintillator is reported.

Several experiments were performed during last years at underground (3600 m w.e.) Laboratori Nazionali del Gran Sasso (LNGS) of the INFN (Italy) to search for resonant 2$\varepsilon0\nu$ captures in 96Ru, 106Cd, 136Ce, 156Dy, 158Dy, 180W, 184Os, 190Pt with the help of HP Ge semiconductor detectors, and ZnWO4 and 106CdWO4 crystal scintillators. No evidence for r-2$\varepsilon0\nu$ decays was found, and only T_{1/2} limits were established in the range of 10^{14}-10^{21} yr., Comment: Proceedings of TAUP 2011 Conference

An experiment to search for 2b processes in 106Cd with the help of 106CdWO4 crystal scintillator (mass of 215 g), enriched in 106Cd up to 66%, is in progress at the Gran Sasso National Laboratories of the INFN (Italy). After 1320 h of data taking, limits on double beta processes in 106Cd have been established on the level of 1019–1020 yr, in particular (all the results at 90% C.L.): T1/2(0ν2e)>3.6×1020 yr, T1/2(2νeβ+)>7.2×1019 yr, and T1/2(2ν2β+)>2.5×1020 yr. Resonant 0ν2e processes have been restricted as T1/2(0ν2K)>1.4×1020 yr and T1/2(0νLK)>3.2×1020 yr. A possible resonant enhancement of the 0ν2e processes is estimated in the framework of the QRPA approach.

A search for double ? processes in 106Cd was carried out at the Gran Sasso National Laboratories of the INFN, Italy; by using a CdWC4 crystal scintillator (mass of 215 g) enriched in 106Cd up to 66%. After 6590 h of data taking, half-life limits on double beta processes in 106Cd were set at level of 1019 ? 1021 yr. A possible resonant enhancement of the 0?2? processes has also been estimated in the framework of the QRPA approach.