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61.
Boris Remenec Silvia Dulanská Ľubomír Mátel Ján Bilohuščin 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):117-122
The behaviour of 95Zr and 95Nb isotopes on TEVA® resin column was studied. The influence of hydrofluoric, hydrochloric, oxalic and sulphuric acids on the separation and chemical yield of zirconium and niobium was tested. The method is suitable for the separation of 93Zr and 94Nb isotopes from hydrofluoric, hydrochloric and sulphuric acid by using different concentrations of the acid for the load or elutes solutions. Samples from reactor and fuel assemblies such as the control-rod connection rod, shielding/absorber parts of fuel rods, neutron in-core measurement channels, pressure vessel basic construction material and internal cladding, core barrel and reactor protection tube unit were analysed. 相似文献
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Heat capacities of concentrated multicomponent aqueous electrolyte solutions at various temperatures
Boris S. Krumgalz Ilan A. Malester Irving J. Ostrich Frank J. Millero 《Journal of solution chemistry》1992,21(7):635-649
The specific heat capacities of the aqueous multicomponent system NaCl +KCl+MgCl2+CaCl2 with ionic strength between 8.3 and 9.6 (resembling Dead Sea waters) were measured between 15°C and 45°C. The obtained data were fitted to an empirical equation as a function of concentration and temperature. The thermodynamic functions of the studied multicomponent system were found to be strongly influenced by changes in MgCl2 concentrations. The application of Young's rule to such concentrated systems was checked at 25°C. The calculated (by Young's rule) specific heat capacitiesC
p and apparent molar heat capacities Cp, of these multicomponent electrolyte solutions were in reasonable agreement with the measured values (–0.008 J-g–1-K–1 and –2.6 J-mol–1-K–1, respectively). 相似文献
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Pramila Selvanathan Gang Huang Thierry Guizouarn Dr. Thierry Roisnel Dr. Guglielmo Fernandez‐Garcia Dr. Federico Totti Dr. Boris Le Guennic Dr. Guillaume Calvez Dr. Kévin Bernot Dr. Lucie Norel Prof. Stéphane Rigaut 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15222-15226
A spiropyran‐based switchable ligand isomerizes upon reaction with lanthanide(III) precursors to generate complexes with an unusual N3O5 coordination sphere. The air‐stable dysprosium(III) complex shows a hysteresis loop at 2 K and a very strong axial magnetic anisotropy generated by the merocyanine phenolate donor. 相似文献
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Atomic force microscope (AFM) imaging and nanoindentation measurements in water were used to probe the mechanical properties of retinal pigment epithelium melanosomes isolated from 14-year-old and 76-year-old donors. Topographic imaging reveals surface roughness similar to previous measurements on dry melanosomes. Force-indentation measurements show different types of responses that were catalogued into four different categories. In these measurements no permanent surface damage of melanosomes was observed as revealed by imaging before and after indentation measurements. The indentation measurements that exhibited nearly elastic responses were used to determine the Young's modulus of melanosomes. The average Young's modulus values are similar for 14-year-old and 76-year-old melanosomes with a somewhat narrower distribution for the 14-year-old sample. These elastic modulus values are considerably higher than the modulus of organelles with cytoplasm (<1 MPa) and approaching values of the modulus of protein crystals (approximately 100 MPa) indicating rather high packing density of biologic material in melanosomes. The width of the Young's modulus distributions is considerable spanning from few megapascals to few tens of megapascals indicating large heterogeneity in the structure. A fraction of the force curves cannot be described by the homogeneous elastic sample model; these force curves are consistent with approximately 10 nm structural heterogeneity in melanosomes. The approach-withdraw hysteresis indicates a significant viscoelasticity, particularly in the samples from the 14-year-old sample. Adhesion of the AFM probe was detected on approximately 3% and approximately 20% of the surface of 14-year-old and 76-year-old samples, respectively. In light of previous studies on these same melanosomes using photoelectron emission microscopy, this adhesion is attributed to the presence of lipofuscin on the surface of the melanosomes. This suggestion indicates that part of the difference in photochemical properties between the old and young melanosomes originates from surface lipofuscin. 相似文献
70.
Molev G Bravo-Zhivotovskii D Karni M Tumanskii B Botoshansky M Apeloig Y 《Journal of the American Chemical Society》2006,128(9):2784-2785
The first tricoordinate fluorosilylenoid, (t-Bu2MeSi)2SiFLi.3THF (1), was synthesized, and its X-ray molecular structure was determined. 1 was synthesized in 40% yield by a bromine-lithium exchange reaction in THF of the corresponding fluorobromosilane with t-Bu2MeSiLi. 1 is best described as an R2SiF- anion attracted to a (Li.3THF)+ cation with a small contribution of resonance structure that consists of a silylene fragment and FLi.3THF. 1 reacts as a nucleophile with MeCl, PhH2SiCl, H2O, and MeOH, as an electrophile with MeLi, and as a silylene with Li (or t-BuLi) and Na, yielding alpha-lithium and alpha-sodium silyl radicals, respectively. Either photolysis or thermolysis of 1 yields the corresponding disilene R2Si=SiR2 (R = t-Bu2MeSi), probably via dimerization of R2Si:. 相似文献