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21.
Electrical resistance measurements at low temperatures and high quasihydrostatic pressures on superconducting and non-superconducting varieties of Y0.8Ba1.2Cu2O5 (obtained by annealing in oxygen and air respectively) show striking anomalies in the vicinity of 100K and 40K. Arguments are presented to show that these anomalies as also the occurrence of T 's in the oxide superconductors either in the vicinity of 100K or of 40K are connected with their layered structure containing planes of Cu-O otahedral complexes.  相似文献   
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An expeditious synthesis of aryl substituted E‐homoallylic bromides has been accomplished by the cleavage of cyclopropylcarbinols with phosphorus tribromide.  相似文献   
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Two new water soluble oxovanadium(IV) complexes with formulae Na[VO(his)(met)SO4] (1) and Na[VO(gly)(met)SO4] (2), (gly=glycine his=histidine, and met=metformin) were synthesized and characterized by LCMS, UV‐Visible absorption, infrared spectra, magnetic moment, elemental analysis, thermal analysis and electronic spectral studies. The metal center was found in an octahedral geometry. DNA binding interaction of these complexes with CT DNA has been explored by UV‐Visible absorption, fluorescence, viscosity measurements and cleavage studies. Finally the binding of the complexes with CT‐DNA could be surface binding, mainly in the groove binding. The complexes were docked in to B‐DNA sequence, 5’(D*AP*CP*CP*GP*AP*CP*GP*TP*CP*GP*GP*T)‐3’ retrieved from protein data bank (PDB ID: 423D), using Discovery Studio 2.1 software.  相似文献   
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Tri-n-butyl phosphate (TBP) is the workhorse of solvent extraction operations in nuclear fuel cycle as well as an important industrial chemical. Its PVT properties are not available in literature. In this study, PVT properties of TBP, estimated using group contribution method, are reported. Wagner constants were also reported in the range of 273.15?K to critical temperature.  相似文献   
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Several solutions of 30 % TBP/n-dodecane were equilibrated with different concentrations of aqueous nitric acid solutions at 298.15 K at a phase ratio of unity. The resultant equilibrated aqueous and organic solutions were analyzed for acidity. A three-solvate model with molecular HNO3 based mechanism was assumed for nitric acid extraction by TBP. With nonlinear chemometric methods, the coefficients were evaluated. With the set of optimized coefficients, derived on the basis of experiments reported in this work, the estimated solvate species and free-TBP species in the TBP containing organic phase were found to be in good agreement with the reported concentrations in the literature.  相似文献   
29.
The phase transition behaviour of the chiral liquid crystal CE6 doped with spherical surface-functionalised CdSe nanoparticles has been examined by means of high-resolution adiabatic scanning calorimetry and polarising microscopy. The addition of nanoparticles results in an essentially stabilised blue phase III. The phase diagram is displayed upon heating and cooling and the enthalpy changes involved in the conversion between the blue phases are determined. The dispersion of functionalised nanoparticles is prominent for the stabilisation of blue phase III, which is potentially useful for applications, especially if applied on liquid crystals that exhibit blue phases close to room temperature.  相似文献   
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Densities of the aqueous dilute solutions of rubidium, cesium, strontium, yttrium, and gallium nitrate were measured at different temperatures ranging from (293.15–343.15) K and atmospheric pressure. From these density values, the apparent molal volumes were calculated and fitted to Masson’s correlation and the temperature dependence was correlated by a second order polynomial. The apparent molal volumes at infinite dilution and experimental slopes have been interpreted in terms of ion–solvent and ion–ion interactions, respectively. The measurements include density as per ASTM D-4052, refractive index (nD25) at sodium D line at 25 °C. Thermal isobaric expansibility was calculated and structure making and structure breaking behaviour of electrolytes were inferred from the sign of the second derivative of apparent molal volumes with respect to temperature at constant pressure. The experimental apparent molal volume was compared with the available literature value.  相似文献   
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