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以N,N′-二氯对苯醌二亚胺、2,5-二甲基-N,N′-二氯对苯醌二亚胺与2,5-二溴-3,4-乙撑二氧噻吩为单体,1,3-二(二苯基膦)丙烷二氯化镍(Ⅱ)为催化剂,采用金属配合物催化法合成了聚(N,N′-对苯醌二亚胺-3,4-乙撑二氧噻吩)和聚(2,5-二甲基-N,N′-对苯醌二亚胺-3,4-乙撑二氧噻吩)两种共聚物。通过红外光谱(FT-IR)、核磁共振(1H-NMR)、凝胶渗透色谱(GPC)、X射线衍射(XRD)、紫外分光光度计(UV-Vis)和循环伏安(CV)等测试对其进行了结构表征及性能测试。结果表明,两种共聚物在CF3COOH(TFA)溶液中的UV-Vis最大吸收波长分别在500 nm和511 nm处;氧化还原峰出现在-0.2 V-0.8 V之间;通过碘掺杂后共聚物的电化学窗口拓宽,电化学活性提高。 相似文献
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报道以两种后过渡金属催化剂二-(2,6-二甲基苯基)-丁二亚胺氯化镍和二-(2-甲基苯基)-丁二亚胺氯化镍所组成的复式催化体系,催化单一乙烯聚合可制备得到长支链(n≥6)的聚乙烯。在合适的聚合条件下此复式催化剂具有很好的协同作用,其催化活性比任一单一催化剂的催化活性都高。本文详细研究了两种催化荆的摩尔比、聚合温度等聚合条件对催化活性及产物结构的影响。用^13C—NMR、FT—IR、DSC对聚合物进行了表征。 相似文献
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改性MgCl2负载α-二亚胺镍催化乙烯聚合 总被引:2,自引:0,他引:2
制备了一种含有胺基官能团α-二亚胺镍配合物,并将该配合物负载在改性MgCl2载体MgCl2/AlRn(OEt)3-n上制备负载催化剂,不用昂贵的MAO(甲基铝氧烷)而用通用烷基铝作助催化剂,研究了其对乙烯的聚合性能。采用高温13C-NMR、高温GPC、差示扫描量热法(DSC)和扫描电镜(SEM)对聚合物进行了研究。结果发现,该催化剂具有很高的催化活性,得到的聚乙烯产品含有各种短支链(甲基、乙基、丙基、丁基)和长支链,分子量在0.35×106和1.08×106之间,分子量分布较窄(2.34~2.93),载体对聚合物具有较好的模板作用。 相似文献
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采用高效液相色谱法测定食品中叔丁基羟基茴香醚(BHA)和2,6-二叔丁基对甲酚(BHT)的含量。结果表明该方法简便、准确、稳定、可靠,可用于叔丁基羟基茴香醚(BHA)与2,6-二叔丁基对甲酚(BHT)的质量控制。 相似文献
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4-(5-氯-2-吡啶)-偶氮-1,3-二氨基苯(5-Cl-PADAB)可与镍发生灵敏的显色反应,生成稳定的配位化合物。基于此建立了一种测定电镀废水中微量镍的光度法。结果表明:在2.0 mol/L HCl介质中,5-Cl-PADAB与Ni(Ⅱ)反应生成摩尔比2∶1的稳定配位化合物,其最大吸收波长为565 nm,表观摩尔吸光系数为6.42×104 L/(mol.cm),Ni(Ⅱ)含量在0~1.0 mg/L内符合比尔定律;该方法用于测定电镀废水中微量镍,结果与催化-分光光度法相符,相对标准偏差小于4.0%,加标回收率为98.5%~101.8%。 相似文献
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火焰原子吸收分光光度法测定多金属矿中高含量的银 总被引:1,自引:0,他引:1
采用火焰原子吸收光谱法直接测定多金属矿中高含量的银,其程序是将样品于700℃高温炉中灼烧1小时,以王水溶矿,在硫脲介质中利用仪器的参比工作方式直接测定样品中银的含量,无需稀释样品溶液,减少了误差。该法简便、快速,结果准确。 相似文献
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A flow injection method for the determination of boron using a conductivity detector has been described. Boric acid injected into the flow system reacts with mannitol (0.3 M) in the mobile phase and an equivalent amount of H(+) is liberated in the stream. The increase in the conductance of the mobile phase due to the liberated H(+) has been equated to the boron concentration in the sample. A linear calibration for light- and heavy-water samples containing 0-20 μg/mL boron was obtained. Boron concentrations in the samples of light and heavy water and lithium pentaborate solution have been measured. The interferences due to various ions such as Na(+), Li(+), Cu(2+), Ni(2+), Co(2+), Fe(3+), Al(3+), SO(4)(2-), NO(3)(-), F(-), and Cl(-) could be eliminated by adopting a two-step sample pretreatment procedure. In the first step, all the anions were converted to Cl(-) by treating the sample solution with a strong anion-exchange resin. In the second step, the solution obtained from the first step was passed through a silver-guard cartridge to remove interfering cations and Cl(-). The relative standard deviation was ±0.25% for the determination of 1 μg of boron in light water, and the limit of detection was 0.01 μg present in an injection volume of 100 μL. The corresponding values for heavy water were ±0.38% and 0.1 μg, respectively. 相似文献
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采用流动注射在线分离富集技术与原子光谱分析法相结合,建立了液-液在线萃取原子吸收光谱测定金的方法,确定了流路参数和操作程序,该法简单、快速、准确,测定的精密度为1.23%,检出限(3σ)为0.018×10~(-6)。 相似文献
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在化学镀镍过程中,建立了流动注射光度法在线实时监测化学镀镍浴中镍浓度随时间变化的方法.流动注射分析采用双流路系统,去离子水作载液,pH=5的醋酸-醋酸钠溶液作试剂流,在395nm波长处测定吸光度A,间歇30min测定一次样品,每隔4 h建立一次工作曲线C(Ni)=a bA.经多次连续8 h运行,工作曲线的相关系数均在0.999左右,以络合滴定法测定结果为标准,本方法大多数测定结果的相对误差在5%左右.该流动注射分析法具有测定装置简单、监测速度较快、再现性好、消耗试剂较少等特点,测定结果的准确度能满足工业分析要求. 相似文献
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A spectrophotometric method is described for determination of methotrimeprazine (levomepromazine). The aim of this work was to develop a simple, rapid, precise, and accurate visible spectrophotometric method for determination of methotrimeprazine in tablet, oral solution, and injection. The method is based on methotrimeprazine reaction with bromophenol blue, resulting in a stable, light yellow-green ion-pair complex that, after extraction with chloroform, presented maximum absorption at 409 nm. Beer's law was obeyed in the concentration range from 5.0 to 25.0 μg/ml. The proposed standardized method was applied to commercially available and simulated samples. The accuracy of the method was confirmed by recovery tests. 相似文献