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81.
Borohydride exchange resin-transition metal(Co,Ni,Cu,)compoundsystems reduced C=C double to C-C single bond in ethanol. 相似文献
82.
利用四氯合金酸和N-4-甲基苯基2-吡啶甲酰胺(HL)反应,合成得到了一种新的Au(Ⅲ)配合物:二氯(N-4-甲基苯基2-吡啶甲酰胺合金(Ⅲ)[Au(L-N,N′)Cl2]。并通过元素分析、红外光谱、核磁共振谱、质谱及X-射线单晶衍射对其进行了表征。结构分析表明,Au(Ⅲ)由二个氮原子和二个氯原子配位,呈平面四方形结构。质谱研究发现,该化合物与5′-单磷酸鸟苷(5′-GMP)反应生成[Au(L-N,N′)(5′-GMP)2]。 相似文献
83.
Su Qin HAN Er Bao LIU Hua LI 《中国化学快报》2005,16(8):1067-1070
This paper reported an indirect flow injection chemiluminescence (FI-CL) method for the determination of the drugs tetracycline (TC), chlortetracycline (CTC) and oxytetracycline(OTC) using Cu( Ⅱ ) as a probe ion. The CL reaction was induced on-line and after injection of the sample the negative peaks appeared as a result of complexation. The method was applied to the determination of TCs in pharmaceuticals and human urine with recoveries in the range95-105%. 相似文献
84.
目的:研究降铅冲剂对低水平铅暴露仔鼠血铅及脑铅的影响,为评价降铅冲剂的作用提供依据。方法:选用Wister大鼠仔鼠60只,体质量80~100 g,随机分成6组,每组10只,分别为空白组、模型对照组、EDTA对照组、降铅冲剂低剂量组、降铅冲剂中剂量组、降铅冲剂高剂量组;造模后开始给药,EDTA对照组给CaNa2EDTA注射液10(mg/kg)/d腹腔注射,降铅冲剂低、中、高剂量组分别予降铅冲剂5(g/kg)/d、10(g/kg)/d、20(g/kg)/d的剂量灌胃,空白组和模型对照组予等量蒸馏水灌胃,给药共30 d。用石墨炉原子吸收光谱仪测定仔鼠血铅、脑铅。结果:(1)染铅后,各染铅组的血铅水平与空白组比较都显著升高(P<0.001),经过30 d的治疗后,各治疗组的治疗后血铅水平均有不同程度下降,与模型对照组比较均有统计学意义。(2)染铅后,各染铅组的脑铅水平与空白组比较都显著升高(P<0.05),治疗后,各组脑铅与治疗前比较均显著升高,降铅冲剂低、中剂量组的脑铅与模型对照组比较显著下降。结论:降铅冲剂能显著降低低水平铅暴露仔鼠的血铅和脑铅含量,其综合疗效优于CaNa2EDTA。 相似文献
85.
铁基超细粒子催化剂具有优良的F-T反应性能。本工作利用原位Mssbauer谱辅以XRD技术研究了含有钾助剂的F-T合成铁基超细粒子催化剂的结构与还原行为,考察了催化剂组成和第二金属组分(Mn,Zn,Mg)的影响。“纯”铁超细粒子催化剂在氢气中很容易经Fe_3O_4还原为零价铁。第二金属组分的引入,一方面阻碍了催化剂的还原,另一方面稳定了Fe~(2+)的存在而使其成为还原的主要中间相,这有利于反应条件下形成类尖晶石结构的活性相。对于Fe-Mn催化剂,上述效应随锰含量的增加而更趋显著。铁基超细粒子催化剂在氢气中的还原能力依“纯”Fe>Fe-Zn>Fe-Mn>Fe-Mg的顺序递减,这在一定程度上反映了铁与第二金属组分之间相互作用的强弱。 相似文献
86.
Fabrication of hexaphenylsilole nanowires and their morphology-tunable photoluminescence. 总被引:1,自引:0,他引:1
Liping Heng Jin Zhai Anjun Qin Yuqi Zhang Yongqiang Dong Ben Zhong Tang Lei Jiang 《Chemphyschem》2007,8(10):1513-1518
Immersion of nanoporous alumina membranes into saturated solutions of hexaphenylsilole with subsequent solvent evaporation affords aligned organic nanowires. The luminescent properties of the hexaphenylsilole nanowires can be manipulated by varying their morphologies, which were controlled by changing the channel sizes of the alumina templates. 相似文献
87.
Observation of a quadrupole plasmon mode for a colloidal solution of gold nanoprisms 总被引:3,自引:0,他引:3
Millstone JE Park S Shuford KL Qin L Schatz GC Mirkin CA 《Journal of the American Chemical Society》2005,127(15):5312-5313
The synthesis and optical properties of single crystalline gold nanoprisms have been investigated. A three-step mediated seed growth process in an aqueous solution generated gold nanoprisms with a relatively homogeneous size distribution. The purity of these nanostructures has allowed us to observe a weak quadrupole resonance in addition to a strong dipole resonance associated with these novel structures. The experimental optical spectra agree with discrete dipole approximation calculations that have been modeled from the dimensions of gold nanoprisms produced in this synthesis. 相似文献
88.
89.
Qin W Baruah M Van der Auweraer M De Schryver FC Boens N 《The journal of physical chemistry. A》2005,109(33):7371-7384
The photophysical properties of seven new 8-(p-substituted)phenyl analogues of 4,4-difluoro-3,5-dimethyl-8-(aryl)-4-bora-3a,4a-diaza-s-indacene (derivatives of the well-known fluorophore BODIPY) in several solvents have been studied by means of absorption and steady-state and time-resolved fluorimetry. For each compound, the fluorescence quantum yield and lifetime are lower in solvents with higher polarity owing to an increase in the rate of nonradiative deactivation. Increasing the electron withdrawing strength of the p-substituent on the phenyl group in position 8 also leads to lower fluorescence quantum yields and lifetimes. When the p-substituent on the phenyl group in position 8 is a tertiary amine [8-(4-piperidinophenyl), 8-(4-N,N-dimethylaminophenyl), and 8-(4-morpholinophenyl)], the low quantum yields of these compounds in more polar solvents can be rationalized by the inversion of the energy levels of an apolar, highly fluorescent and a polar, nonfluorescent excited state, where charge transfer from the tertiary amine to the BODIPY unit occurs. These amine analogues can be protonated at low pH in aqueous solution. Fluorescence titrations yielded pK(a) values of their conjugate ammonium salts which are in agreement with the electron donating tendency of the amine group: piperidino (4.15) > dimethylamino (2.37) > morpholino (1.47), with the pK(a) values in parentheses. The rate constant of radiative deactivation (k(f)) is the same for all compounds in all solvents studied (k(f) = 1.4 x 10(8) s(-1)). 相似文献
90.
Guo Yang Zhu Rong Wang Guo Hua Liu Li Qun Xu Bei Zhang Xia Qin Wu College of Life Environment Science Shanghai Normal University Shanghai China State Key Laboratory of Chema/Biosensing Chemometrics Hunan University Changsha China 《中国化学快报》2007,18(6):633-635
Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte). 相似文献