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1.
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   

2.
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   

3.
卟啉吡啶季铵盐分光光度法测定水中痕量铜   总被引:2,自引:0,他引:2  
在pH1.0邻苯二甲酸氢钾-盐酸缓冲溶液中,新卟啉吡啶季铵盐显色剂——溴化5-[4-N-(对硝基)苄铵基吡啶基]-10,15,20-三(4-N-吡啶基)卟啉与铜(Ⅱ)形成1∶1配合物。在此显色反应中,新卟啉试剂具有显色和表面活性剂双重功能。此配合物的最大吸收波长为427.0nm,表观摩尔吸光率为1.78×105L.mol-1.cm-1,铜(Ⅱ)质量浓度在0.12mg·mL-1以内符合比耳定律。该方法应用于3个环境水样中铜(Ⅱ)的测定,测定值与已知值的平均相对误差均小于4%  相似文献   

4.
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   

5.
催化光度法测定痕量铜   总被引:4,自引:0,他引:4  
痕量铜对生命活动很重要。人体中铜的代谢与铁的代谢有相关性,铜参于造血过程,缺铜会引起贫血病。因此鉴于铜的重要生理作用,各生物样品中痕量铜的测定日益受到重视。已有文献[2,3]报道利用催化光度法测定铜。但高碘酸钾-溴邻苯三酚红体系尚未见报道,铜在乙酸-乙酸钠介质中对上述体系有催化褪色作用。据此建立了测定痕量铜的新方法。本法测定范围为0~5μg/10ml,表观摩尔吸光系数ε=1.26×10~5,用于茶叶中铜的测定得到较好结果。1 试验部分1.1 主要试剂与仪器 Cu(Ⅱ)标液:0.1mg·ml~(-1),准确称取CuSO_4·5H_2O 0.0982g,用去离子水溶解。稀释于50ml量瓶中。工作液稀释为0.1μg·ml~(-1) 溴邻苯三酚红溶液:1.0×10~(-3)mol·L~(-1) 高碘酸钾溶液:5.0×10~(-4)mol·L~(-1) 乙酸-乙酸钠缓冲液:pH=6.0 1,10-菲罗啉溶液:2g·L~(-1) 试剂均为分析纯,水为去离子水  相似文献   

6.
研究了新试剂5-[4-(3-N-甲基麻黄素丙氧基)苯基]-10,15,20-三(4-甲氧苯基)卟啉溴化物与Cu(Ⅱ)的显色反应,试验表明,在pH4的HOAc-NaOAc缓冲溶液中,沸水浴加热7min,形成M:R=2:3的络合物,λmax=418nm,在0~200μg·L-1范围内吸光度与Cu(Ⅱ)的浓度符合比耳定律,加入乙醇能提高灵敏度,=4.2×105.方法具有灵敏度高及干扰少的特点,用于测定水样中痕量Cu(Ⅱ),结果满意.  相似文献   

7.
吖啶黄催化荧光法测定痕量铜的研究   总被引:15,自引:0,他引:15  
研究了在氨-氯化铵缓冲介质中,Cu(Ⅱ)催化过氧化氢氧化吖啶黄退色,利用使其荧光减弱的指示反应,建立了催化荧光法测定痕量铜的新方法.铜的线性范围为8.0×10~4~8.O×10~(-3)μg·ml~(-1),检出限为5.0×10~(-4)μg·ml~(-1).方法应用于水、人发和纯铝中痕量铜的测定,结果满意.  相似文献   

8.
合成了偶氮安替比林Ⅲ,或按系统命名法为3,6-二(安替比偶氮)-4,5-二羟基-2,7-萘二磺酸试剂,探讨该试剂与铜(Ⅱ)显色的适宜条件及其共存离子的影响,提出了测定铜的显色反应体系.在pH为10.0~11.5范围内,铜(Ⅱ)与试剂形成1:1配合物,最大吸收波长为590nm,表观摩尔吸光率为5.1×104L·mol-1·cm-1.铜的质量浓度在50μg/25 mL以内符合比耳定律.方法已用于铜矿及铝合金中铜(Ⅱ)的测定.  相似文献   

9.
:试验制备了一种荧光试剂5,10,15-三苯基-20-吡啶基卟啉(TPPyP),该试剂激发光谱(λ_(ex))为420nm时,在650nm波长处有发射光谱(λ_(em))峰。当试剂与铅(Ⅱ)反应时产生荧光猝灭现象。提出了以此试剂为荧光探针测定痕量铅(Ⅱ)的荧光光度法。在邻苯二甲酸盐-盐酸缓冲溶液中,一定量的十六烷基三甲基溴化铵(CTMAB)存在下,通过测定样品溶液和空白溶液在发射波长650nm的荧光强度,计算得反应液荧光强度的降低程度△F;结果表明:△F值与铅(Ⅱ)的质量浓度在1.0×10~(-4)~1.5×10~(-3)mg·L~(-1)范围内呈线性关系,方法的检出限(3s/k)为4.0×10~(-5)mg·L~(-1)。此方法用于膨化食品中铅(Ⅱ)的测定,回收率在95.0%~107.0%之间,相对标准偏差(n=6)小于3%。  相似文献   

10.
研究了显色剂镉试剂A(对硝基苯基重氮氨基偶氮苯 ,CadionA)析相光度法测定痕量铜的试验条件。结果表明 ,在 pH 10的Na2 B4 O7 NaOH缓冲介质中 ,2 0 %OP乳化剂的存在下 ,于95± 1℃水浴中加热 4 5min ,镉试剂与铜生成稳定红色配合物 ,配位比为R∶M =2∶1,λmax=514nm ,ε514 =3.85× 10 5L·mol- 1·cm- 1,铜量在 0~ 7μg/50ml范围内符合比耳定律 ,与一般光度法相比 ,方法灵敏度较高 ,摩尔吸光系数提高 3倍 ,检出限为 7.2× 10 - 9g·ml- 1。此法用于铝合金样品和发样中痕量铜的测定 ,结果满意  相似文献   

11.
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   

12.
13.
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   

14.
15.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

16.
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   

17.
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   

18.
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   

19.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

20.
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   

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