Now showing items 9572-9591 of 14235

    • Y(RA)_3·4H_2O 的合成及其抗白血病HL-60细胞的研究 

      李勤喜; 宋玉民; 王流芳; 王印月 (2004-02-28)
      在避光、无水、无氧条件下合成了维甲酸钇的配合物;;通过元素分析、摩尔电导、红外光谱、紫外光谱、差热及热重分析对配合物的结构和性质进行了表征;;其分子式为Y(RA)3·4H2O.采用MTT比色法及NBT还原试验分别研究了该配合物及全反式维甲酸(HRA)对HL-60细胞增殖的影响.结果表明;;二者均具有抑制HL-60细胞增殖及诱导其分化的作用;;尤其配合物对HL-60细胞的作用很明显;;优于全反式维甲酸(P<0.01).
    • Y_2O_3修饰Ni/SiO_2催化剂在甲烷部分氧化制合成气反应中的催化性能及稳定性 

      王雅莉; 李琪; 翁维正; 夏文生; 万惠霖 (2016-11-15)
      采用常规浸渍法制备Y_2O_3修饰的Ni/SiO_2催化剂,并考察其催化甲烷部分氧化(POM)制合成气反应性能。结果表明,Y_2O_3的引入减小了金属Ni的粒径,有效提高了Ni在载体表面的分散性,增强了金属Ni与载体SiO_2间的相互作用,从而使催化剂的抗烧结、抗积碳能力,以及催化剂的POM反应性能得以改善。
    • YF-1型萤光分光光度计的改进 

      黄贤智; 阮源萍; 陈国强 (1983-06-30)
      经改进的YF—1型萤光分光光度计以卤钨灯为光源,玻璃稜镜单色器为激发单色器和发射单色器,光电倍增管为光电检测元件、四位数字显示。仪器灵敏度高,可检测0.1ppb萤光素;线性范围宽,可定量测定0.1—1000ppb萤光素;稳定性好,双份测定精密度优于1.5%。波长范围360—800nm,可供例行定量分析,亦可用于测绘萤光激发光谱和萤光发射光谱。若采用萤光同步扫描技术,可作测绘萤光同步谱和进行萤光同步分析。该仪器还配有固体萤光附件和化学发光 ...
    • YF-1型萤光分光光度计的研制 

      黄贤智; 翁心桥 (1981-08-29)
      YF-1型萤光分光光度计采用汞灯光源,以干涉滤光片代替激发单色器,玻璃棱镜为发射单色器,光电倍增管作光电检测元件。四位数字显示。仪器灵敏度高,可检测0.05ppb硫酸奎宁;线性范围宽,可定量测定0.1—1000ppb的硫酸奎宁;稳定性好,双份测定精密度优于±1%。可供例行定量分析,亦可用于测绘萤光发射光谱,波长范围360—30.nm。
    • (Z)-5-amino-2-dibenzylamino-1-phenyl-6-(2-pyridyl)hex-4-en-3-one 

      Meng, J.; Zheng, J. F.; Fang, H.; Jin, L. R.; 郑剑峰 (2006-03)
      The title compound, C31H31N3O, was obtained by the reaction of 4-dibenzylamino-3-oxo-5-phenylpentanenitrile with 2-methylpyridinylmagnesium chloride. The crystal structure involves intermolecular N-(HO)-O-... hydrogen bonds.
    • Zero- and two-dimensional organization of tetrahedral cadmium chalcogenide clusters with bifunctional covalent linkers 

      Zheng, Nanfeng; 郑南峰; Bu, Xianhui ( Calif State Univ Long Beach, Dept Chem & Biochem); Lauda, Jason ( Univ Calif Riverside, Dept Chem); Feng, Pingyun ( Univ Calif Riverside, Dept Chem) (AMER CHEMICAL SOC, 2006-09-05)
      Few examples are known in which chalcogenide clusters are assembled with organic ligands into crystallographically ordered covalent superlattices even though molecular crystals of such clusters have been known for decades. ...
    • Zero-point vibrational corrections to isotropic hyperfine coupling constants in polyatomic molecules 

      Chen, Xing; Rinkevicius, Zilvinas; Cao, Zexing; 曹泽星; Ruud, Kenneth; Agren, Hans (ROYAL SOC CHEMISTRY, 2010-11-09)
      The present work addresses isotropic hyperfine coupling constants in polyatomic systems with a particular emphasis on a largely neglected, but a posteriori significant, effect, namely zero-point vibrational corrections. ...
    • Zhao-Lun Fang - Obituary 

      Huang, Benli; 黄本立 (SPECTROCHIM ACTA B, 2008-04)
    • ZIF-8-Based Quasi-Solid-State Electrolyte for Lithium Batteries. 

      Sun Cui; Zhang Jin-Hua; Yuan Xiang-Fei; Duan Jia-Ning; Deng Sheng-Wen; Fan Jing-Min; Chang Jeng-Kuei; Zheng Ming-Sen; Dong Quan-Feng (2019-12-18)
      The quasi-solid-state electrolytes (QSSEs) with an inorganic skeleton, a solid-liquid composite material combining their respective merits, exhibit high ionic conductivity and mechanical strength. However, most quasi-solid ...
    • Zigzag boron-carbon nanotubes with quasi-planar tetracoordinate carbons 

      Zhang, Congjie(Shaanxi Normal Univ, Sch Chem & Mat Sci); Sun, Wenxiu(Shaanxi Normal Univ, Sch Chem & Mat Sci); Cao, Zexing; 曹泽星 (AMER CHEMICAL SOC, 2008-04)
      Four kinds of novel zigzag boron-carbon nanotubes with quasi-planar tetracoordinate carbons (2m, 0, 1) (m = 3-6; i = 1-4) have been constructed, and their structures, stabilities, and bonding properties have been investigated ...
    • Zinc Chelation with Hydroxamate in Histone Deacetylases Modulated by Water Access to the Linker Binding Channel 

      Wu, Ruibo; Lu, Zhenyu(NYU, Dept Chem); Cao, Zexing; 曹泽星; Zhang, Yingkai(NYU, Dept Chem) (AMER CHEMICAL SOC, 2011-04-01)
      It is of significant biological interest and medical importance to develop class- and isoform-selective histone deacetylase (HDAC) modulators. The impact of the linker component on HDAC inhibition specificity has been ...
    • Zinc oxide thin film synthesized by combustion chemical vapor deposition 

      Wu,QH; Li,ZY; Li,J; Xu,FC; 徐方成 (2008-12-30)
      Zinc oxide (ZnO) thin film was prepared on quartz substrate by combustion chemical vapor deposition. Its surface morphology, crystal structure, chemical stoichiometry and optical properties were investigated using scanning ...
    • Zinc(II) coordination polymer with a unique entanglement PTS structure 

      Long, L. S.; 龙腊生; Zheng, L. S.; 郑兰荪 (2003-03)
    • Zinc-Catalyzed Asymmetric Formal [4+3] Annulation of Isoxazoles with Enynol Ethers by 6π Electrocyclization: Stereoselective Access to 2H-Azepines. 

      Zhu Xin-Qi; Wang Ze-Shu; Hou Bo-Shang; Zhang Hao-Wen; Deng Chao; Ye Long-Wu (2019-11-13)
      6π electrocyclization has attracted interest in organic synthesis because of its high stereospecificity and atom economy in the construction of versatile 5-7-membered cycles. However, examples of asymmetric 6π electrocyclization ...
    • [Zn(C7H3O5N)]n center dot nH(2)O: A third-order NLO Zn coordination polymer with spiroconjugated structure 

      Zhou, Guo-Wei; Lan, You-Zhao; Zheng, Fa-Kun; Zhang, Xin; Lin, Meng-Hai; 林梦海; Guo, Guo-Cong; Huang, Jin-Shun (ELSEVIER SCIENCE BV, 2006-08)
      [Zn(C7H3O5N)](n) (.) nH(2)O (1) possesses an anticlockwise windmill-like framework structure and formats spiroconjugation over the infinite molecular layer that is predicted to have large static third-order polarizability ...
    • [Zn-8(SiO4)(C8H4O4)(6)](n): the firstborn of a metallosilicate-organic hybrid material family (C8H4O4 = isophthalate) 

      Yang, SY; 杨士烑; Long, LS; 龙腊生; Huang, RB; 黄荣彬; Zheng, LS; 郑兰荪 (ROYAL SOC CHEMISTRY, 2002-01-14)
      [Zn-8(SiO4)(C8H4O4)(6)](n) (C8H4O4 = isophthalate), synthesized by hydrothermal reaction, possesses a diamondoid framework structure constructed from hexahedron-like Zn-8(SiO4) cores and C8H4O4 linkers and remains stable ...
    • Zn-Ni/HZSM-5催化剂上微波辐射诱导正己烷芳构化 

      程志林; 孙兆林; 刘赞 (2002-03-18)
      对微波辐射条件下,Zn-Ni/HTSM-5催化剂上正已烷的芳构化反应,考察了反应条件对反应性能的影响,并与常规加热下的反应性能进行了比较。结果表明,在微波加热条件下,在一定程度上提高反应温度可以获得明显高的总芳烃收率和BTX收率,亦明显地改变BIX中各组分的相对选择性;但随着反应时间的延长,反应性能的波动比常规加热时大。对微波辐射诱导催化反应的作用机理也进行了探讨。
    • Zn-ZrO2/H-ZSM-5双功能催化剂上合成气转化制汽油馏分的研究 

      何顺; 沈政; 常浩浩; 刘志铭; 康金灿; 张庆红; 王野 (2019-01-10)
      针对合成气直接转化制汽油馏分反应,合成了Zn-ZrO2金属氧化物与沸石分子筛复合的双功能催化剂,结果显示Zn-ZrO2/H-ZSM-5具有较高的CO转化率和汽油馏分选择性。考察了反应温度和接触时间对Zn-ZrO2和Zn-ZrO2/H-ZSM-5双功能催化剂的影响,证实了合成气经甲醇/二甲醚中间体制汽油馏分的反应路径。研究了Zn/Zr摩尔比、H-ZSM-5分子筛的Si/Al比对催化性能的影响,结果表明Zn/Zr摩尔比为1∶32、Si/Al ...
    • ZnNi/HZSM-5催化剂上混合C_4烃的芳构化反应 

      程志林; 晁自胜; 万惠霖; 孙兆林; 刘赞 (2002-02-28)
      考察了ZnNi/HZSM 5催化剂制备方法和反应条件对混合C4烃芳构化反应的影响 ,并探讨了反应机理。结果表明 :(1)在ZnNi/HZSM 5催化剂制备过程中 ,采用先浸渍Zn2 + 后浸渍Ni2 + 的方法可以获得性能好的催化剂 ;(2 )混合C4烃在ZnNi/HZSM 5上的芳构化反应有最佳温度范围 ,在该温度范围内可以获得高的BTX的收率及选择性 ;(3)低的质量空速有利于芳构化反应 ,空速升高会因催化剂结焦而使BTX的收率及选择性下降 ...
    • ZnO nanorod coating for solid phase microextraction and its applications for the analysis of aldehydes in instant noodle samples 

      Ji, Jiaojiao; Liu, Haihong; Chen, Jinmei; Zeng, Jingbin; Huang, Jianli; Gao, Leihong; Wang, Yiru; Chen, Xi; 陈曦 (ELSEVIER SCIENCE BV, 2012-07-13)
      Zinc oxide (ZnO) nanorods based solid-phase microextraction (SPME) coating was directly prepared on stainless steel wires using in situ hydrothermal growth method. This coating has high surface-to-volume ratio with a ...