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991.
992.
Alexey B. Nadykto Fangqun Yu Jason Herb 《International journal of molecular sciences》2008,9(11):2184-2193
Hydration directly affects the mobility, thermodynamic properties, lifetime and nucleation rates of atmospheric ions. In the present study, the role of ammonia on the formation of hydrogen bonded complexes of the common atmospheric hydrogensulfate (HSO4−) ion with water has been investigated using the Density Functional Theory (DFT). Our findings rule out the stabilizing effect of ammonia on the formation of negatively charged cluster hydrates and show clearly that the conventional (classical) treatment of ionic clusters as presumably more stable compared to neutrals may not be applicable to pre-nucleation clusters. These considerations lead us to conclude that not only quantitative but also qualitative assessment of the relative thermodynamic stability of atmospheric clusters requires a quantum-chemical treatment. 相似文献
993.
A. Ya. Eremin Ya. B. Kukolev R. R. Gilyazetdinov L. A. Makhortova Yu. V. Stepanov N. V. Tsarev 《Coke and Chemistry》2008,51(11):434-439
The efficiency of selective crushing with pneumomechanical separation is investigated as a function of the quality of the coal batch and the operating conditions of the fluidized-bed separator. 相似文献
994.
Veysel T. Yilmaz Evrim Senel Canan Kazak 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(3):407-413
The reaction of [Cu(sac)2(H2O)4] · 2H2O with 2-methylpyrazine (mpyz) leads two complexes, concomitant crystallization of a mononuclear complex [Cu(sac)2(mpyz)(H2O)2] (1) and a polymeric complex [Cu(sac)2(μ-mpyz)]n (2). Both complexes have been characterized by elemental analyses, magnetic measurements, FT-IR and ESR, TG-DTA and single-crystal
X-ray diffraction analyses. Single-crystal X-ray analyses show that complex 1 consists of discrete molecules in which the copper(II) ions exhibits a square-pyramidal coordination geometry. The individual
molecules of 1 are connected into a hydrogen-bonded chain structure, which is further assembled to form a three-dimensional network by π–π stacking interactions.
Complex 2 is an 1D coordination polymer in which copper(II) centers are bridged by the mpyz ligand. The chains are further assembled
to form two-dimensional frameworks by π–π and C–H···π stacking interactions. 相似文献
995.
996.
Haruo Mimura Ryusei Sato Yu Sasaki Yuichi Furuyama Akira Taniike Kazutoshi Yoshida Akira Kitamura 《International journal of molecular sciences》2008,9(10):1989-2002
Tributyltin (TBT) released into seawater from ship hulls is a stable marine pollutant and obviously remains in marine environments. We isolated a TBT resistant marine Pseudoalteromonas sp. TBT1 from sediment of a ship’s ballast water. The isolate (109.3 ± 0.2 colony-forming units mL−1) adsorbed TBT in proportion to the concentrations of TBTCl externally added up to 3 mM, where the number of TBT adsorbed by a single cell was estimated to be 108.2. The value was reduced to about one-fifth when the lysozyme-treated cells were used. The surface of ethanol treated cells became rough, but the capacity of TBT adsorption was the same as that for native cells. These results indicate that the function of the cell surface, rather than that structure, plays an important role to the adsorption of TBT. The adsorption state of TBT seems to be multi-layer when the number of more than 106.8 TBT molecules is adsorbed by a single cell. 相似文献
997.
998.
999.
S. M. Obraztsov G. A. Birzhevoi Yu. V. Konobeev V. A. Pechenkin V. I. Rachkov 《Atomic Energy》2006,101(5):809-815
The results of a neuronet simulation of the shift of the temperature of a ductile-brittle transition of VVéR-440 vessel materials
as a function of the neutron fluence and chemical composition are presented. Existing data on the temperature shift of the
ductile-brittle transition in control samples of the main metal and the weld-seam material in VVéR-440 vessels from different
units of an operating nuclear power plant are used for model development. The model is used to determine the character and
degree of influence of various alloying elements on the radiation embrittlement of vessel steel. The dependence of the shift
of the temperature of the ductile-brittle transition on the neutron fluence is estimated.
__________
Translated from Atomnaya énergiya, Vol. 101, No. 5, pp. 353–358, November, 2006. 相似文献
1000.