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991.
V. P. Chizhkov V. N. Boitsov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(2):298-302
The Gibbs energy increment during the distillation of a dilute solution in a separation cascade was calculated. An interpretation of the minimum work thermodynamically required during the symmetric separation of a binary mixture is suggested. 相似文献
992.
Yu. A. Lisitsyn A. V. Sukhov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(6):1033-1034
Cathodically initiated amination of anisole has been performed with the Ti(IV)-NH2OH system in aqueous solutions of 4 M H2SO4 containing high concentration of acetic acid or acetonitrile. In electrolyses performed to reach full conversion of hydroxylamine, the isomeric anisidines obtained (2 para/ortho ∼ 3.9) with total yields referred to the current and amino radical source exceeded 80%. 相似文献
993.
A new and green method for the synthesis of α,β-unsaturated arylsulfones had been achieved through the condensation of aromatic aldehydes,chloroacetonitrile,benzenesulfinic acid sodium salt in the presence of l-butyl-3-methyl imidazolium hydroxide([bmim]OH) in EtOH under reflux.The ionic liquid was recovered and recycled for subsequent reactions.The advantages of this protocol were non-toxic,easy work-up and good yields. 相似文献
994.
Polypropylene/poly(butyl methacrylate)(PP/PBMA) blends were prepared by diffusion and subsequent polymerization of butyl methacrylate(BMA) in commercial isotactic polypropylene(iPP) pellets.The diffusion kinetics,diametrical distribution of PBMA in a pellet and phase morphology of a typical PP/PBMA blend were investigated. 相似文献
995.
A rapid,sensitive,selective and reliable strip assay based on DNA-functionalized gold nanoparticles for Hg2+ detection has been developed,with a detection limit 5 nmol/L.The measurement principle was based on thymine-Hg2+-thymine(T-Hg2+-T) coordination chemistry and streptavidin-biotin interaction.The major advantages of this assay are that results can be read visually without any instrument in less than 10 min and that it does not require any sample pretreatment. 相似文献
996.
997.
998.
A method to predict the enthalpies of vaporization of ethers with various structures under normal conditions using a modified Randič method is proposed. 相似文献
999.
N. V. Pervukhina S. V. Borisov S. A. Magarill N. V. Kuratieva N. N. Mozgova I. V. Chaplygin 《Journal of Structural Chemistry》2012,53(3):588-592
Heyrovskyite mineral Pb6Bi2S9 from fumarole exhalations of the Kudryavyi volcano (Iturup island, Kurils, Russia) is studied by X-ray crystallography (Bruker Nonius X8 Apex with a 4K CCD detector, R = 0.0405). Unit cell parameters are: a = 4.1457(1) ?, b = 13.7421(5) ?, c = 31.5005(12) ?, V = 1794.6(1) ?3, Z = 4, d x = 7.216 g/cm3, Cmcm space group, R=0.0405. The resulted structure is similar to the known structures of heyrovskyites from other deposits with some variation in the cation composition. 相似文献
1000.
R. S. Corrêa S. R. Souza e Silva L. P. Duarte G. D. F. Silva L. C. A. Barbosa J. Ellena A. C. Doriguetto 《Journal of Structural Chemistry》2012,53(1):156-163
The structural study of two (C30H48O2) pentacyclic triterpene (PCTT) isomers is presented. These terpenes, known as 30-hydroxy-lup-20(29)-en-3-one (1) and (11α)-11-hydroxy-lup-20(29)-en-3-one (2), were isolated from Maytenus imbricata Mart. Ex Reissek (Celastraceae). The molecular structure of 1 and 2 differs in the position of the hydroxyl group. Both compounds crystallize in non-centrosymmetric space groups with two molecules in the asymmetric unit. The crystal structure of 1 shows a triclinic P1 space group (a = 9.5518(1) ?, b = 9.7083(1) ?, c = 14.4696(2) ?, α = 93.832(1)°, β = 102.833(1)°, and γ = 103.307(1)°), while compound 2 crystallizes in a monoclinic P21 one (a = 13.4439(16) ?, b = 14.4463(14) ?, c = 13.5224(9) ? and β = 99.703(8)°). The two molecules independent by symmetry of 1 differ slightly due to the presence of static disorder in oxygen atoms. In addition, the intermolecular geometries of 1 and 2 were analysed, and in each isomer the crystal packing is stabilized by O-H…O intermolecular hydrogen bonds and van der Waals forces. 相似文献