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新型卟啉吡啶季铵盐的合成与应用 总被引:2,自引:0,他引:2
采用微波技术合成了3种新型吡啶卟啉季铵盐:溴化5-[4-N-(对硝基)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉、氯化5-[4-N-(对甲氧基)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉和氯化5-[4-N-(对氯)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉.化合物的结构采用紫外可见光谱、红外光谱、核磁共振谱、质谱、元素分析测试技术得到确认.在分光光度法测定水中的痕量铜离子的显色反应中,配合物的表观摩尔吸光系数都在1×105L/(mol·cm)以上,是一种高灵敏度显色剂.该卟啉试剂具有显色和表面活性剂双重功能,应用于环境水样中铜的测定得到了满意的结果. 相似文献
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张志华 《理化检验(化学分册)》2013,(6):751-752
卟啉化合物已作为显色剂用于铜、铁、银、铅、锌等多种金属离子的测定[1-6],效果良好。新型卟啉显色剂——氯化5-[4-N-(对氯)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉[7]已应用于水中铜离子的测定[8]。该卟啉试剂同时具有显色和表面活性剂双重功能,水溶性好、抗干扰能力强、灵敏度高。 相似文献
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以卟啉吡啶季铵盐为显色剂分光光度法测定水中痕量铜 总被引:4,自引:1,他引:3
应用新试剂5-[4-N-(对氯)-苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟吩氯化物作显色剂,用分光光度法测定了痕量铜,在pH 3.2的邻苯二甲酸盐缓冲介质中,此试剂与铜离子生成组成比为1比1的稳定配合物,其吸收峰位于428.0 nm波长处,表观摩尔吸光率为1.9×105L·mol-1·cm-1.铜含量在0.1 mg·L-1以内符合比耳定律,其线性回归方程为A=0.0152 0.31 C(r=0.999 1).按所提出的方法测定了3种环境水标准样品中的痕量铜(Ⅱ),测得结果与标准值相符. 相似文献
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合成了一种新型水溶性吡啶卟啉季铵盐即溴化5-[(4-N-苄基)吡啶基]10,15,20-(4-N-吡啶基)卟啉,探索了其合成、分离及纯化方法,用1H-NMR,UV,IR 和MS确证了其结构.新的卟啉试剂与Cu(Ⅱ)进行显色反应,在酸性介质中,沸水浴加热15 min形成1:1的络合物,λmax=426 nm,在0~0.10 μg/mL范围内吸光度与铜质量浓度关系符合比尔定律,ε=1.62×105(L·mol-1·cm-1),该法已应用于环境水试样中痕量铜离子的分析. 相似文献
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为探讨甲基取代基对四苯基卟啉(TPPH2)结构和性质的影响,以四苯基卟啉与铜[Ⅱ]显色反应为参照,采用条件实验方法,对比研究了四(间甲苯基)卟啉(TMPPH2)和四(3,4-二甲苯基)卟啉(TDMPPH2)与铜Cu[Ⅱ]的显色反应,采用摩尔比法和连续变化法测定了配合物组成。结果表明:TMPPH2和TDMPPH2与Cu[Ⅱ]的显色配合物最大吸收峰与TPPCu的相同:均在416 nm处;TPPH2、TMPPH2和TDMPPH2与Cu[Ⅱ]进行显色反应的溶液最佳pH值分别是8、9和7,水浴温度100℃,最佳加热时间分别是20、20和25 min;形成配合物的组成分别是1:1、2:1和2:1(n卟啉:n铜);由此可知间甲基和3,4-二甲基取代对四苯基卟啉铜的配合物B吸收带(Soret带)峰位无影响,但对配合物的组成影响明显。 相似文献
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卟啉吡啶季铵盐与铜(Ⅱ)显色反应的研究 总被引:4,自引:0,他引:4
研究了在不使用表面活性剂情况下,卟啉试剂溴化5 [4 (2 吡啶乙氧基)苯基] 10,15,20 三(4 甲氧基苯基)卟啉与铜(Ⅱ)的显色反应,结果表明,pH3~5时,铜(Ⅱ)与卟啉吡啶季铵盐形成了稳定配合物,其表观摩尔吸光系数为2.68×105L·mol-1·cm-1。铜(Ⅱ)浓度在0~0 7μg/10ml范围内服从比耳定律,配合物其组成的摩尔比为Cu∶卟啉吡啶季铵盐=1∶2,方法应用于环境水样中铜的测定,结果满意。 相似文献
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采用新卟啉试剂T(3-M-4-HP)P对进行对Cu(Ⅱ)的显色反应研究.结果表明,在阴离子表面活性(?)(?)BS存在下,pH5.7时,Cu(Ⅱ)与T(3-M-4-HP)P形成很稳定的配合物,具有很高灵敏度.配合物的摩尔吸光系数为4.76×10~5.Cu(Ⅱ)与T(3-M-4-HP)P的组成比为1:2.Cu(Ⅱ)量在0~0.8μg/10ml范围内服从比耳定律,本法用于铝合金中微量铜的测定,结果满意. 相似文献
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合成并表征了 [5- o-(乙氧羰基甲氧基苯基 )-10,15,20-Tri(4-N-甲基吡啶基 )]卟啉 H_2[( 5-o- (Emoph)-Tri(4-N- Mepy)]PP(1)及其铜配合物 Cu[( 5- o- (Emoph)-Tri(4- N- Mepy)]PP(2),用紫外可见光谱滴定法测定了配合物 (2)与单核苷酸的配位平衡常数,研究了它作为主体分子和单核苷酸的相互作用。研究结果表明,各配体结合常数按 K(dGMP) >K(dAMP) >K(dTMP) >K(dCMP)≥ K(dUMP)的顺序依次减小。测定了π-π配合反应的Δ_rG,Δ_rH,Δ_rS,发现该反应是放热,熵减小的过程,该反应体系存在焓熵补偿关系。 相似文献
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研究了四(4-氯苯基)卟啉与微量铅(Ⅱ)的显色反应,探讨了显色剂、硼砂-氢氧化钠,表面活性剂Tween-80等的用量以及反应时间对配合物的生成以及稳定性的影响.结果表明,在pH=10的硼砂氢氧化钠缓冲溶液及Tween-80微乳液中,铅(Ⅱ)与四(4-氯苯基)卟啉形成1∶1的稳定配合物.配合物的最大吸收位于466 nm波长处,表观摩尔吸光系数ε=2.5×105L·mol-1·cm-1,铅(Ⅱ)浓度在160 μg·L-1范围内符合比耳定律.方法用于环境水样中铅的测定,获得较好的结果. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献