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991.
A study of the kinetics of the oxidation by peroxodisulfate of macrocyclic complexes of nickel(II) with a pH-regulatable position of the thermodynamic equilibrium between the tetra- and hexacoordinated forms showed that the square-planar form is substantially more reactive than the hexacoordinated form. The observed effect may be a consequence of different mechanisms of the redox processes: intraspheral in the first case and extraspheral in the second.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, Nos. 5–6, pp. 442–447, September–December, 1992. 相似文献
992.
Preparation,stability and two-dimensional ordered arrangement of gold nanoparticles capped by surfactants with different chain lengths 总被引:2,自引:0,他引:2
Gold nanoparticles modified with C10NH2, C12NH2, C16NH2 and C18NH2 respectively have been prepared by the reverse micelle method. Nanoparticles stability and their two-dimensional (2D) ordered arrangement were studied by UV-Vis absorption spectra and LB technique. The factors, such as the chain length and the size distribution of particles, which affect the 2D ordered arrangement formation, are discussed. Experimental results show that the longer the chain length of surfactants capping the gold nanoparticles, the more stable the nanoparticles, and the more ordered 2D arrangement of gold nanoparticles. 相似文献
993.
The morphology evolution in immiscible polymer-liquid-crystal systems is quite different from flexible polymer-polymer mixtures due to the anisotropic properties of liquid crystals. The dynamics and rheology of such system are discussed. A theoretical model is proposed to describe the dynamics of liquid-crystal droplets in a flow field and the rheological properties of immiscible liquid-crystal/polymer mixtures. The deformation of liquid-crystal droplet is found to be greatly dependent on the interfacial properties of polymer-liquid crystal. The scaling relationships of interfacial contribution to the stresses are found to be quite different from the isotropic mixtures with droplet morphology. 相似文献
994.
The low specificity of the electron-impact positive-ion mass spectrum in relation to the structure of an aromatic aglycone has been shown. The glycosidic moiety is determined unambiguously from the pattern of the mass spectrum. The dissociative electron-capture mass spectra are sensitive to the nature of the substituents of the aromatic nucleus of the aglycone. The influence of the aglycone is most pronounced in cases with substituents having high electron affinities.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok, Institute of Biochemistry, Academy of Sciences of the Armenian SSR, Erevan, Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 623–628, September–October, 1984. 相似文献
995.
996.
A. Ya. Lazaris S. M. Shmuilovich A. N. Egorochkin 《Chemistry of Heterocyclic Compounds》1976,12(3):361-365
The reaction of triethylammonium salts of -acyldithiocarbazic acids with sodium chloroacetate and hydrazine leads to the formation of mesoionic 1-amino-1,3,4-triazole-2-thiones, which react with aldehydes to give the corresponding azomethine derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 424–428, March, 1976. 相似文献
997.
Dragulescu-Andrasi A Zhou P He G Ly DH 《Chemical communications (Cambridge, England)》2005,(2):244-246
Guanidine-based peptide nucleic acid (GPNA) with a d-backbone configuration and alternate spacing binds sequence-specifically to RNA and is readily taken up by both human somatic and embryonic stem (ES) cells. 相似文献
998.
在 1× 1 0 - 3 Pa~ 4 GPa的压力和 5 80~ 930 K温度范围内 ,利用高压技术并结合机械球磨 ,研究了压力、温度和晶粒尺寸对α-Fe与非晶 BN的固态反应的影响 .发现高压和晶粒细化可以极大地促进α-Fe和非晶 BN的固态反应过程 ,α-Fe与非晶 BN发生固态反应的临界晶粒尺寸约 8nm.压力和温度对反应产物及其晶体结构有明显影响 .2 GPa和 80 0 K时 ,反应产物为具有正交结构的 Fe-N新相 ;在 3~ 4 GPa和 690~80 0 K时 ,可形成单一ε-Fex N合金相 ;而在 4 GPa和 930 K以上 ,反应产物由 Fe-N合金相转变为 Fe3B相 相似文献
999.
提出了一种铁矿粉热加工生产工艺中亚铁含量测定的新方法。在氮气保护下,用盐酸溶出样中的亚铁,在硫磷混酸介质中以重铬酸钾标准溶液滴定,并对溶样条件进行了研究。该方法简单、快速、准确,已成功地应用于氧化催化法生产氧化铁中亚铁的控制分析和成品鉴定。 相似文献
1000.
Yi‐Hang Wen Xia Feng Yin‐Hua He You‐Zhao Lan Hong Sun 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m504-m506
In the title complex, [Zn(C12H6O4)(H2O)]n, a ZnII polymer based on naphthalene‐1,8‐dicarboxylate (1,8‐nap), the ZnII atoms adopt an elongated octahedral coordination geometry. A zigzag chain is formed by μ2‐aqua ligands and μ2‐carboxylate groups of the 1,8‐nap ligands. Adjacent parallel chains are further linked by 1,8‐nap ligands, forming a twisted two‐dimensional layer structure along the (100) plane. 相似文献