共查询到17条相似文献,搜索用时 78 毫秒
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以正交设计法试验研究了二安替比林对氯苯基甲烷试剂分光光度法测定微量钒的最佳显色条件。最佳显色条件为 :(1+5 ) H3PO4 用量为 4 .0 0 m L,0 .2 m ol· L- 1 Mn( )的用量为 2 .0 0 m L,10 g· L- 1 Tween80用量为 2 .0 0 m L ,2 g· L- 1 DAPCM用量为 3.0 0 m L ,加热温度为 90℃ ,加热时间为 5 5 m in,最大吸收波长为 4 85 nm。V( )在 0 .2 0~ 5 .0 0 μg· (2 5 m L) - 1范围内呈良好线性关系 ,线性回归方程为 A=0 .92 11+0 .35 14 C[μg· (2 5m L) - 1 ],线性相关系数 r=0 .9979,摩尔吸光系数 ε=1.0 3× 10 6 [L· (mol· cm) - 1 ]。本法应用于猪骨中钒 ( )的测定 ,结果满意 相似文献
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以正交试验设计法研究了二安替比林对乙氧基苯基甲烷 (DAp EM)试剂与微量钒 ( )的超高灵敏显色反应 ,建立了测定钒 ( )的新体系。该体系的灵敏度为 ε=8.30× 10 6 L· mol- 1· cm- 1 ,线性范围为 2 .0 0~ 10 .0μg· L- 1 ,对测定 0 .2 0 μg· (2 5 m L) - 1 V( ) ,抗主要离子干扰量为 :Fe3+ ,Cu2 + (10 μg) ;Ce( ) (5 μg) ;F- (0 .5μg)。与单因素轮换法建立的体系相比 ,灵敏度和选择性有了很大的改善。该方法测定中草药样品中微量钒 ( )含量 ,结果满意 相似文献
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以正交试验设计法研究了二安替比林对乙氧基苯基甲烷(DApEM)试剂与微量钒(Ⅴ)的超高灵敏显色反应,建立了测定钒(Ⅴ)的新体系.该体系的灵敏度为ε=8.30×106L@mol-1@cm-1,线性范围为2.00~10.0μg@L-1,对测定0.20μg@(25 mL)-1V(Ⅴ),抗主要离子干扰量为Fe3+,Cu2+(10μg);Ce(Ⅳ)(5μg);F-(0.5μg).与单因素轮换法建立的体系相比,灵敏度和选择性有了很大的改善.该方法测定中草药样品中微量钒(Ⅴ)含量,结果满意. 相似文献
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L. H. Tagle F. R. Diaz D. Radic A. Opazo J. M. Espinoza 《Journal of Inorganic and Organometallic Polymers》2000,10(2):73-79
Poly(amides) (PAs) derived from bis(4-aminophenyl)-diphenylgermane and bis(4-aminophenyl)-diphenylsilane, and terephthaloyl, isophthaloyl, and tetrachloroterephthaloyl chlorides, were synthesized in N, N-dimethylacetamide solution. The products were characterized by IR and NMR spectroscopy. The results were in agreement with the proposed structures. The yields were almost-quantitative for PAs derived from terephthaloyl and isophthaloyl chlorides. However, the yields from the diacid tetrachloroterephthaloyl chloride were very low due to low reactivity. The inherent viscosity values of all PAs measured in o-chlorophenol were very similar. Thermogravimetric analysis indicated that the Ge-containing PAs were more stable than were those containing Si due to the higher polarity of the C–Si bond. The PAs derived from tetrachloroterephthaloyl chloride are exceptions owing to the influence of the chlorine atoms. The glass transition temperatures (Tg) were determined for all the PAs. The PAs derived from the Si-containing diamine have a value higher than that for the Ge-containing diamine. 相似文献
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L. H. Tagle F. R. Diaz J. C. Vega M. Quezada P. Guerrero 《Journal of Inorganic and Organometallic Polymers》2003,13(1):21-28
Poly(carbonates) derived from diphenols that contain Si or Ge and bisphenol A bis(chloroformate) have been synthesized using phase-transfer conditions. The products were characterized by spectroscopic methods. Two phase-transfer catalysts and three molar ratios of NaOH/diphenol were used. The results were evaluated by the yields of product and their inherent viscosities. The data were compared with materials obtained without the catalyst and showed that the new synthetic technique was effective for the synthesis of these types of poly(carbonates). An increase in the concentration of NaOH and the phase-transfer catalysts increased the yields and
inh values compared to those obtained with stoichiometric quantities of NaOH. It is proposed that the differences in electronegativities of the heteroatoms in the diphenols are responsible for this behaviour. 相似文献
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研究了 3, 3′ 二甲基 4, 4′ (2 氨基噻唑偶氮)联苯(DATABP)在pH为 12. 0 ~12. 5的强碱性介质中与溴化十六烷基三甲铵(CTMAB)、溴化十六烷基吡啶 (CPB)及溴化十四烷基吡啶 (TPB) 3种的反应。实验表明DATABP与各表面活性剂均形成络合比为 1∶1的绿色络合物。对CTMAB、CPB及TPB体系,络合物的最大吸收波长分别为 620nm、630nm和 640nm,表观摩尔吸光系数分别为 5. 60×103、5. 52×103 和 3. 07×103L·mol-1·cm-1。用所建立的方法测定了水中的CPB,结果满意。 相似文献