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71.
Koga T Seo YS Zhang Y Shin K Kusano K Nishikawa K Rafailovich MH Sokolov JC Chu B Peiffer D Occhiogrosso R Satija SK 《Physical review letters》2002,89(12):125506
We report an anomalous swelling of polymer thin films in carbon dioxide (CO(2)) which is associated (in both locus and form) with the density fluctuation ridge that forms along the extension of the coexistence curve of gas and liquid in the P-T phase diagram. Neutron reflectivity results showed that CO(2) could be sorbed to a large extent ( approximately 60%) in thin polymer films even when the bulk miscibility of the polymer with CO(2) is very poor. The anomalous swelling is found to scale with the polymer radius of gyration (R(g)) and extends to a distance approximately 10 R(g). 相似文献
72.
This paper is concerned with the analysis of dynamic deflection and acceleration of a concrete bridge which is subjected to a moving vehicle load. The bridge, to be constructed across the River Brahmaputra in India, consists of 20 main spans, and each main span is assumed to be double cantilever type with a small suspended span. The moving vehicle is modeled as one degree of freedom. The deflections and accelerations at specific locations on the bridge when the vehicle moves at constant speed are analyzed by using the finite element method. 相似文献
73.
74.
N. A. Keiko L. G. Stepanova I. D. Kalikhman M. G. Voronkov 《Russian Chemical Bulletin》1977,26(7):1522-1524
Conclusions A number of new 2,5-dialkylthio-2-formyl-2, 3-dihydro--pyrans was synthesized via the Mannich reaction using alkylthioacetaldehydes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1652–1655, July, 1977. 相似文献
75.
Tsykhanskaya I. I. Vlasova N. N. Keiko V. V. Sakharovskii V. G. Balashenko L. V. 《Russian Chemical Bulletin》1970,19(12):2596-2599
Russian Chemical Bulletin - 相似文献
76.
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78.
N. A. Keiko L. G. Stepanova I. D. Kalikhman M. G. Voronkov 《Russian Chemical Bulletin》1986,35(3):663-666
Conclusions The nucleophilic or radical addition of thiols to -alkoxyacroleins leads to 2-alkoxy-3-organylthiopropanals. Depending on the reaction conditions, the product of the electrophilic reaction of the same reagents is a 2-alkoxy-2-organylthiopropanal or 1-alkoxy-1-organylthiopropanone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 722–724, March, 1986. 相似文献
79.
[reaction: see text] New Lewis acid-assisted Br?nsted acids (LBAs), tin(IV) chloride-2,6-dialkoxyphenols, serve as artificial cyclases for biomimetic polyene cyclization. For example, the enantioselective cyclization of 4-(homogeranyl)toluene using tin(IV) chloride-2,6-di[(1'R,2'R)-trans-2'-(3' ',5' '-xylyl)cyclohexanoxy]phenol gave a trans-fused tricyclic compound with 85% ee. 相似文献
80.
[reaction: see text] [60]Fullerenoacetyl chloride, one of the reactive derivatives of [60]fullerenoacetic acid, was isolated and identified for the first time. This acid chloride was easily synthesized in good yield from tert-butyl [60]fullerenoacetate through two steps. In the presence of 4-(dimethylamino)pyridine as a base, the acid chloride smoothly reacted with various alcohols under mild conditions to give the corresponding esters including [60]fullerene-biomolecule hybrids in moderate to high yields. 相似文献