共查询到20条相似文献,搜索用时 46 毫秒
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SynthesisandCrystalStructureofRE[CH2(CH2)4CONC4H9]3(NO3)3(RE=Dy,La)WangHanzhang(王汉章),XuQingfeng(徐庆锋),QianPu(钱朴)SunJianping(孙建... 相似文献
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研究了超高纯氧化钽和超高纯氧化铌试验与生产的工艺技术条件,进行了超高纯氧化钽和超高纯氧化铌的基础试验、中试和工业性生产试验,介绍了项目产品的技术指标和用户使用情况。 相似文献
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合成了2,3-二氯异丁酸根和4-甲基吡啶氮氧化物稀土三元配合物(RE=La、Ce、Pr、Nd、Sm、Eu).通过元素分析、红外、紫外、荧光、X射线粉末衍射、XPS、热分析以及摩尔电导等分析手段,确定了配合物的组成为[REL3(4-picNO)H2O](L= CH3C2H2Cl2COO -),并对它们的性质进行了讨论. 相似文献
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A new process for electrolytic production of a perfluorinated compound, (CF3)3N, using lanthanum nickel oxide-coated Ni sheet anode in the (CH3)4NF·4.0HF melt at room temperature, was developed. Thin films of the lanthanum nickel oxides were prepared on Ni sheets by sol-gel coating method using polyvinlylpyrrolidone(PVP). The main components of the thin films were La2O3, LaNiO3, and La2NiO4 at 500, 750 and 1000 ℃, respectively. The anode performance in the (CH3)4NF·4.0HF melt depends greatly on the main component of the thin film, and the LaNiO3-coated Ni sheet anode gives the best anode performance. The potential of LaNiO3-coated Ni sheet anode remains constant at 5.9 V during electrolysis at 20 mA·cm-2 in the (CH3)4NF·4.0HF melt for 100 h. This is because LaNiO3 and NiF3 and/or Ni2F5, the latter of which was formed during electrolysis, in the film give a high electronic conductivity to the surface film during electrolysis. The maximum mole fraction of (CF3)3N (21.4%) was obtained at 20 mA·cm-2 in (CH3)4NF·4.0HF melt using the LaNiO3-coated Ni sheet. 相似文献
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JA van Dorst CJ van Heusden JM Tikkanen JP Kamerling JF Vliegenthart 《Canadian Metallurgical Quarterly》1997,297(3):209-227
Seven analogues of the trisaccharide beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-->O)(CH 2)7CH3 have been synthesized as potential substrates for glycosyltransferases involved in the chain-termination of N-acetyllactosamine-type N-glycans. These compounds include: 3-O-methyl-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp -(1-->O) (CH2)7CH3, 3-deoxy-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1 -->O) (CH2)7CH3, 3-deoxy-3-fluoro-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-M anp- (1-->O)(CH2)7Ch3, 3-amino-3-deoxy-beta-D-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Ma np- (1-->O)(CH2)7CH3, beta-D-Gulp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-- >O)(CH2)7CH3, beta-L-Galp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1-->O)(CH 2)7CH3, and alpha-L-Altp-(1-->4)-beta-D-GlcpNAc-(1-->2)-alpha-D-Manp-(1- ->O) (CH2)7CH3. All trisaccharides were obtained by condensation of suitably modified glycosyl donors based on imidates or thioglycosides with the same disaccharide acceptor, octyl 3,4,6-tri-O-benzyl-2-O-(3,6-di-O-benzyl-2-deoxy-2-phthalimido-beta-D- glucopyranosyl)-alpha-D-mannopyranoside, followed by deprotection. 相似文献
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R Ryberg 《Canadian Metallurgical Quarterly》1985,31(4):2545-2547
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Although schedule-dependent cytotoxicity of etoposide has been reported, its mechanisms have not been elucidated fully. In this study, we attempted to clarify what concentration, time or exposure dose (ED, concentration of drug x time) of etoposide result in the antitumor effect on human ovarian cancer cells from the standpoint of cell cycle perturbation. The different ED were produced by different drug treatment schedules: 10 microgram/ml x 4 h (ED 40), 1.66 microgram/ml x 24 h (ED 40), 5 microgram/ml x 4 h (ED 20), 0.83 microgram/ml x 24 h (ED 20), 10 microgram/ml x 0.8 h (ED 8), 5 microgram/ml x 1.6 h (ED 8), 2 microgram/ml x 4 h (ED 8), 0.33 microgram/ml x 24 h (ED 8). Cell cycle perturbation on day 5 and the suppression of cell growth were dependent on the drug concentration at the lowest exposure dose (ED 8), but were dependent on ED at the higher EDs (20 or 40). The percentage of cells in the G2/M fraction significantly decreased from day 5 to day 7 in BG-1 cells treated at ED 20 or treated with higher concentrations (10 and 5 microgram/ml) at ED 8, but not in those treated at ED 40 or treated with lower concentrations (2 and 0.33 microgram/ml) at ED 8. Therefore, the cytotoxic mechanism of etoposide may not be explained by simple schedule dependency. 相似文献
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合成了硝酸钇(Ⅲ)与双希夫碱N,N′-二亚水杨基乙二胺、二甲基亚砜的配合物〔Y(C6H4OHCHNC2H4NCHC6H4OH)(NO3)3(CH3SOCH3)〕。x—射线单晶结构分析表明该晶体属单斜晶系、空间群为P21/n,a=0.9631(2)nm,b=1.6414(5)nm,c=1.6209(3)nm,β=102.98(2)°,Z=4,Dx=1.653Mg·m-3。Y(Ⅲ)配位数为9,配位几何为畸变的单帽四方反棱柱,所有的配位原子均为氧原子,分别来自三个硝酸根,一个二甲基亚砜和二个双希夫碱,中心离子被双希夫碱桥联,组成一维无限长链。 相似文献
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The chemical equilibrium composition of the system Fe3O4 + 4CH4, at 1300 K and 1 atm consists of solid Fe and a 2:1 gas mixture of H2 and CO. Thermogravimetric (TG) analysis combined with gas Chromatographic measurements was conducted on the reduction of
Fe3O4 (powder, 2-μm mean particle size) with 2.3, 5, 10, and 20 pct CH4 in Ar, at 1273, 1373, 1473, and 1573 K. The reduction proceeded in two stages, from Fe3O4 to FeO, and finally to Fe. CR, conversion and H2 yield increased with temperature, while the overall reaction rate increased with temperature and CH4 concentration. C (gr)
deposition, due to the cracking of CR,, was observed. By applying a topochemical model for spherical particles of unchanging
size, the reaction mechanism was found to be mostly controlled by gas boundary layer diffusion. The apparent activation energy
reached a maximum at 30 pct reduction extent and decreased monotonically until completion. When compared with the results
using instead either H2 or CO as reducing gas, the reduction achieved completion faster using CH4, at temperatures above 1373 K. 相似文献