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11.
T. P. Bochkareva B. V. Passet K. R. Popov N. V. Platonova T. I. Koval'chuk 《Chemistry of Heterocyclic Compounds》1987,23(10):1084-1089
A novel method has been developed for the synthesis of sulfonic acids of five-membered heterocycles containing two heteroatoms, with a solution of sulfur trioxide in 1,2-dichloroethane. High yields of the required products are obtained, under conditions which are mild in comparison with those used in earlier methods. The mechanism of sulfonation is discussed, and some azole·SO3 complexes have been obtained and described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1353–1359, October, 1987. 相似文献
12.
种植沙生植物--沙棘改善内蒙古地区生态环境 总被引:2,自引:0,他引:2
结合内蒙古地区现状,对沙棘的生物学和生态学特性、沙棘属植物化学成分和微量元素及种植沙生植物——沙棘的重要性和必要性进行了详细的研究和探讨。研究表明,沙棘属植物具有极强的生态适应性并富含多种营养成分和生物活性物质,并以耐干旱、耐瘠薄、萌蘖及固氮能力强等特点被称为治理非宜林地水土流失、改善生态环境的先锋树种。种植沙棘是治理内蒙古脆弱生态环境最经济、最有效的措施,是贫瘠的不毛之地发展经济、增加收入的经济树种。另外.种植沙棘的技术简便,容易掌握,投资少,见效快。 相似文献
13.
Sharutin V. V. Sharutina O. K. Senchurin V. S. Platonova T. P. Nasonova N. V. Pakusina A. P. Gerasimenko A. V. Sergienko S. S. 《Russian Journal of Coordination Chemistry》2001,27(9):669-675
Heating of a solution of pentaphenylantimony in toluene in atmospheric oxygen affords -oxo-bis(tetraphenylantimony) (I) in a 63% yield. The latter compound can be converted to bis(tetraphenylantimony) carbonate or phthalate by the action of carbon dioxide or phthalic anhydride, respectively. According to X-ray diffraction data, the antimony atoms in compound Ihave a distorted trigonal-bipyramidal coordination (Sb–O 2.0050(4) Å, the SbOSb angle 151.71(9)°). The molecule of bis(tetraphenylantimony) phthalate is composed of two equal fragments, and its Sb atoms also have trigonal-bipyramidal coordination (Sb–O 2.2421(8) Å; Sb–C 2.176(1), 2.115(1), 2.130(1), and 2.137(1) Å). 相似文献
14.
Sharutin V. V. Sharutina O. K. Osipov P. E. Platonova T. P. Pakusina A. P. Fukin G. K. Zakharov L. N. 《Russian Journal of Coordination Chemistry》2001,27(7):483-485
2-tert-Butylphenoxytetraphenylantimony Ph4SbOC6H4(Bu-t)-2 was prepared by the reaction of pentaphenylantimony with 2-tert-butylphenol in toluene at 20°. The structure of the obtained compound was determined by X-ray diffraction. The Sb atom in this compound has a distorted trigonal-bipyramidal coordination with the aroxy group in the axial position. The Sb–C(Ph)eqand Sb–C(Ph)axdistances are 2.111(7)–2.138(7) and 2.180(7) Å the Sb–O and O–CArdistances are 2.143(4) and 1.363(8) Å, respectively. The C(Ph)axSbOAraxial angle is 174.1(2)°, while the SbOC angle is 126.7(4)°. 相似文献
15.
K. S. Platonova 《Differential Equations》2017,53(6):796-808
We obtain relations that define the equivalence algebra of the family of one-dimensional Boltzmann equations f t + cf x + F(t, x, c)f c = 0 and show that all equations of that form are locally equivalent. We carry out the group classification of the equation with respect to the function F in the special case where the function F and the transformations of the variables t and x are assumed to be independent of c. We show that, under such constraints for the transformation and the family of equations, the maximum possible symmetry algebra is eight-dimensional, which corresponds to an equation with a linear function F. 相似文献
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18.
以内蒙古地区沙棘果实为原料,研究了提取黄色素的工艺条件,同时对该色素的性质进行了初步探讨。结果表明,以95%的乙醇溶液作浸提剂,提取的黄色素浓度最高,工艺流程简单易行,且无毒,无污染。对提取的黄色素进行的性质试验表明,沙棘黄色素对光、热具有较好的稳定性,适用于酸性或弱碱性的食品中,葡萄糖、氧化剂(H2O2)、还原剂(Na2SO3)等食品添加剂均无明显影响以上结果为这种优良天然色素的开发与应用提供了参考。 相似文献
19.
Sharutin V. V. Sharutina O. K. Pakusina A. P. Platonova T. P. Zadachina O. P. Gerasimenko A. V. 《Russian Journal of Coordination Chemistry》2003,29(2):89-92
Tetraphenylantimony chloride and bromide were synthesized through the reaction of pentaphenylantimony with diphenylantimony trichloride or tribromide taken at a molar ratio of 2 : 1 in toluene. When the initial compounds were taken at a molar ratio of 1 : 1, triphenylantimony dichloride or dibromide was formed. The phenylation of triphenylantimony sulfate with pentaphenylantimony yielded tetraphenylantimony sulfate. According to the X-ray diffraction data, the antimony atom in the tetraphenylantimony chloride molecule has a distorted trigonal bipyramidal configuration with the chlorine atom in the axial position. The Sb–Cl distance is equal to 2.686(1) and Sb–C distances are equal to 2.113(4) and 2.165(4) Å (av. 2.130 Å). 相似文献
20.
Sharutin V. V. Sharutina O. K. Platonova T. P. Pakusina A. P. Gerasimenko A. V. Gerasimenko E. A. Bukvetskii B. V. Popov D. Yu. 《Russian Journal of Coordination Chemistry》2003,29(1):11-15
Tetraphenylantimony N,N-dimethyldithiocarbamate (I) and tetra-p-tolylantimony N,N-dimethyldithiocarbamate (II) were synthesized via the reaction of tetraarylantimony chloride Ar4SbCl (Ar = C6H5 or C6H4Me-4) with sodium N,N-dimethyldithiocarbamate in water. According to the X-ray diffraction data, the tetraarylantimony N,N-dimethyldithiocarbamate molecules have a distorted octahedral configuration. The Sb–S bond lengths are equal to 2.7158(5) Å, 2.7440(5) Å and 2.761(2) Å, 2.8002(2) Å for I and II, respectively. 相似文献