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11.
本文报道以3α-羟基-6-羰基-5α-胆烷酸甲酯(3)为原料经六步反应合成了油菜甾醇类似物25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇(9a).总产率14%.9a的促进植物生长作用是24-表油菜甾醇内酯的60%. 相似文献
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Tetsuro Kawahara Kazuhiro Doushita Hiroaki Tada 《Journal of Sol-Gel Science and Technology》2003,27(3):301-307
Anatase TiO2 films (thickness = 50 nm) were formed in shape of stripes (width = 1.6 mm, interval = 0.4 mm) by gravure printing on commercially available SnO2 coated soda-lime glass substrates (dimension = 300 × 300 mm). Its photocatalytic activity was examined for the gas-phase oxidation of CH3CHO in comparison with a simple TiO2 photocatalyst formed on a silica glass. The patterned TiO2/SnO2 bilayer type photocatalyst showed a high photocatalytic activity in an H2O bearing atmosphere. On the other hand, neither the patterning nor stacking effect was observed for the same reaction under dry conditions. These results could be explained in terms of the reducing potential of the electrons in the conduction band of the SnO2 layer. 相似文献
14.
SynthesisandCrystalStructureofMnSm_4(SiO_4)_3O¥ChiLi-Sheng;DengShui-Quan;ZhuangHong-Hui;HuangJin-Shun;(StateHeylaboratoryofStr?.. 相似文献
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S. V. Baires D. É Vallen K. M. Enikeev A. S. Khramov V. E. Bel'skii A. V. Il'yasov B. E. Ivanov 《Russian Chemical Bulletin》1992,41(10):1801-1804
The interaction of synthetic analogs of active centers of iron-sulfur proteins with phosphates of different structures was studied. It was shown that the process involves ligand exchange and obeys the first-order reaction kinetic equation. The most rapid exchange occurred with the most acidic compound diphenyl phosphate.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2301–2305, October, 1992. 相似文献
18.
Nikodem Tomczak 《European Polymer Journal》2007,43(5):1595-1601
Patterning of silicon substrates with poly(amidoamine) generation 5 (PAMAM-G5) dendrimers using soft lithographic microcontact printing (μCP) is presented. μCP is shown to yield monolayers of dendrimers patterned with high level of definition over μm2 to mm2 areas. The patterns are stable over a period of weeks, which is attributed to the suppressed diffusion of partially charged G5 PAMAM on oxidized silicon. However, the dendrimers studied were shown to be relatively weakly bound to the substrate when subjected to lateral stresses. In aqueous conditions most of the dendrimers desorbed from the substrate. 相似文献
19.
Two amino acid analog resistant mutants of the cyanobacteriumAnabaena sp 287 were isolated after MNNG mutagenesis.Anabaena ST 16, a mutant resistant to the alanine analog D-α-aminobutyric acid andAnabaena ST 25, another mutant resistant to the histidine analog l,2,4-triazole-3-alanine, released alanine and histidine, respectively,
into the medium upon immobilization in alginic acid during diazotrophic growth in fluidized bed reactors. The rates of amino
acid production by the mutants were 4.3 μmol mg chl-1 h-1 of D-alanine byAnabaena ST 16 and 16.6 μnol mg chl-1 h-1 of L-histidine byAnabaena ST 25. Nitrogen fixation by the mutants was not affected by the extracellular amino acid concentration. While the radioactive
carbon flow was followed, the parent strain retained 93% of fixed14C and released only 7% into the medium. On the other hand,Anabaena ST 16 released 13% andAnabaena ST 25 released 29% into the medium. These mutants are beneficial in the production of radioactive amino acids using diazotrophic
photobiotechnology. 相似文献
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I. L. Odinets O. I. Artyushin E. A. Antonov P. V. Petrovskii B. I. Freger T. A. Mastryukova M. I. Kabachnik 《Russian Chemical Bulletin》1994,43(1):121-124
It was shown by31P and13C NMR spectroscopy that methyl(3-carboxy-3-oxopropyl)phosphinic acid (4-methylhydroxyphosphinyl-2-oxobutyric acid) (1) and the amide (2) of the latter exist in keto forms in non-aqueous solutions. In aqueous solutions an equilibrium between the keto,gem-diol, and enol forms has been observed. The proportions of the diol and enol forms increase as the acidity of the media increases. Silylation of acid 1 with hexamethyldisilazane gives the tris(trimethylsilyl) derivative of enol form (3) (Z- andE-isomers).Translated fromIzyestiya Akadetnii Nauk. Seriya Khimicheskaya, No. 1, pp. 125–128, January, 1994. 相似文献