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1.
胆绿素的极谱测定研究王琰(重庆建筑工程学院基础学科系重庆630045)李自林(重庆师范学院化学系重庆630047)关键词:胆绿素,极谱导数波,极谱测定胆绿素(biliverdin,简称BV)是人体内存在的重要胆色素之一、是血红素降解为胆红素的中间产物...  相似文献   

2.
胡椒碱的极谱分析研究   总被引:4,自引:0,他引:4  
孟召辉  汪振辉 《分析化学》1994,22(12):1263-1266
在pH2.2的Britton-Robinson缓冲溶液中,胡椒碱在-1.10V(us.SCE)左右产生一灵敏的极谱波,导数峰电流与胡椒碱浓度在0.05-8μg/ml范围内呈良好的线性关系。本法操作简便,快速,灵敏,选择性较好。用于天然胡椒果实中胡椒碱的测定,得到了满意结果。本文对极谱波性质及电极反应机理进行了研究。  相似文献   

3.
血红素的极谱行为研究   总被引:4,自引:0,他引:4  
曾石麟  李东辉 《分析化学》1991,19(7):742-745
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4.
5.
交流示波极谱基础研究(IV):切口的性质   总被引:5,自引:1,他引:4  
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6.
在NaH2PO4-Na2HPO4(pH=9.0)缓冲溶液中,萘丁美酮在-0.62V处产生一个灵敏的极谱波.导数波高与萘丁美酮的浓度在0.5~25.0μg/mL范围内呈良好的线性关系,检出限为0.06μg/mL.通过对萘丁美酮的极谱波行为的分析,探讨了电极反应机理,建立了测定微量萘丁美酮的分析方法.  相似文献   

7.
交流示波极谱图重现性的研究   总被引:5,自引:2,他引:5  
本文用集成运放为主要元件改进了交流示波极谱的实验线路,并用该线路在严格控制实验条件的情况下,对交流示波极谱图的重现性进行了系统的研究。实验表明,交流示波极谱图的重现性良好,可将其用于有机化合物及有机药物的定性鉴定。  相似文献   

8.
9.
Antilg de/dt—E曲线上的示波极谱滴定法   总被引:3,自引:2,他引:3  
杨昭亮  高鸿 《分析化学》1989,17(10):870-874
在示波极谱滴定中,当去极剂切口位于示波极谱图|dE/dt|的最大值附近时,利用Antilg dE/dt~E示波图来指示滴定终点能使终点变化更为敏锐。原来较难进行滴定的一些体系现在可用这种方法滴定。在50Hz的交流电频率下,用氨羧络合剂滴定了Cd~(2+)、Pb~(2+)、Zn~(2+)、Co~(2+),滴定结果符合分析要求。非线性放大还可应用于以dE/dt~E示波图的扩张或收缩来指示滴定终点的示波极谱滴定法及以荧光电位线的伸长或收缩来指示滴定终点的示波电位滴定法,以提高终点变化的敏锐性。以亚硝酸钠滴定对氨基苯磺酸为例说明了这一方法的可行性。  相似文献   

10.
极谱催化波法测定甘草酸   总被引:20,自引:0,他引:20  
过玮  宋俊峰 《分析化学》1996,24(7):835-837
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11.
李南强  张力  高小霞 《化学学报》1983,41(4):351-358
In a supporting electrolyte containing 2X10-4M Alizarin Red S, 0.1M NH3-NH4Cl and at pH 9.6, we obtained an adsorptive complex wave of gadolinium-Alizarin Bed S by single-sweep polarography. The peak potential of the derivative wave is -0.69V (S. C. E.). The limit of detection for gadolinium is 6X10-8M. We have determined the composition of the complex which is 1:3 GD-Alizarin Red S and confirmed that the wave is an adsorptive complex wave. The electrode processes may be presented as follows: Gd3+ + 3HL2- + 3NH3 = (GdL3)6- + 3(NH4)^+ (Chemical reaction) (GdL3)6- = (GdL3)ad6- (Surface process) The total electrochemical reaction is (GdL3)ad6- + 6e + 6(NH4)^+ = (Gd(LH2)3)ad6- + 6NH3  相似文献   

12.
焦奎  高小霞 《化学学报》1983,41(3):222-228
In this paper the polarographic behavior of terbium-oxine(Ox)- sodium perchlorate system has been studied. In the solution of NaClO4, Ox has a well defined single-sweep polarographic wave P1. After the addition of Tb3+ a new wave P2 appears at more negative potential. A linear calibration curve of the decrease of P1 is obtained in Tb3+ concentration range from 1.0X10-6M to 1.0X10-5M under the optimun conditions of pH4.0-4.5, 0.1M NaClO4-8X10-5M Ox. The wave height of P2 increases linearly with Tb3+ concentration from 3.0X10-6M to 3.0X10-5M in 0.1M NaClO4-2.0X10-4M Ox. It has been shown by applying a number of polarographic techniques that the wave is an adsorptive complex wave. We proposed the reduction processes of the complex and determined the dissocation constants of Ox.  相似文献   

13.
锗(IV)-茜素红-VOSO4-EDTA体系极谱吸附催化波研究   总被引:1,自引:0,他引:1  
李南强  崔毅  何红兵 《化学学报》1987,45(4):399-402
报导了在酸性缓冲液中锗(IV)-茜素红-VOSO4-EDTA体系的配合吸附平行催化波的研究.锗的最低检出量为1.0x10^-^9mol.dm^-^3.研究了催化波的机理.  相似文献   

14.
钴-二氮菲一硫脲体系的极谱催化波   总被引:1,自引:0,他引:1  
赵藻藩  王愚 《化学学报》1983,41(8):761-764
In 8*10^-^7M phenanthroline-0.02M thiourea medium (ethanolamine buffer, pH =8.3), by using Na2SO3 to remove dissolved oxygen, cobalt ion can produce a sensitive catalytic wave with a peak shape on dc polarography. Ep=1.62V (vs. S.C.E.), detection limit is 1 X 10^-^1^0M. There is a linear dependence of peak height on cobalt concentration over a range of 2 X 10^-^1^0 - 4 X 10^-^8 M. Common ions which are not more than 1000-fold of Co^2^+ do not interfere the determination of cobalt, except Ni^2^+ and As^3^+ which are permitted to only 125 and 300-fold respectively. Good results are obtained in determining traces of cobalt in various samples by this method.  相似文献   

15.
铝-邻苯二酚紫络合吸附波的研究   总被引:3,自引:0,他引:3  
邻苯二酚紫在NH4Ac(pH4.7)底液中还原,产生良好的示波极谱图,Ep1=-0.66V(vs.SCE).加入A13+后,此波高降低,并在稍负的电位上出现一个尖峰形的新波(EP2=-0.85V),其峰电流与铝的浓度在1×10-6-1.2×10-5M范围成正比,此波可用于测定铝,实验表明,该波属于络合吸附波,用连续变化法确定络合物的络合比为1:1。  相似文献   

16.
在单扫示波极谱仪上,罗丹明B在氯化铵底液中(0.4M)的导数波(-1.45V,SCE)是一个吸附波,加入Sm3+能降低它的波高,二苯胍(1×10-4M)的存在使罗丹明B(8.4×10-5M)的波形稳定,Sm3+浓度为3×10-7-2×10-3M时,浓度与波峰的降低呈线性关系。在直流极谱仪上,在有二氧六圜存在的氯化铵底液中,钐(Ⅲ)-罗丹明B络合物在-1.7V(SCE)有一个吸附还原波。在最佳条件下(0.1M氯化铵,4.2×10-5M罗丹明B和10%二氧六圜,pH=5.0),在浓度为2×10-5-2×10-5M范围内,波高与Sm3+浓度有正比关系。比较了稀土-罗丹明B在二氧六圜中的极谱波,销比钐灵敏,铒最灵敏;但是罗丹明B的吸附波妨碍了在它后面的络合物波的灵敏度进一步提高。  相似文献   

17.
铜(Ⅱ)-咪唑络合吸附波的研究   总被引:1,自引:0,他引:1  
本文提出极谱测定微量铜的铜(Ⅱ)-咪唑新体系。以0.2mol/LNaOH为底液,该体系在单扫示波极谱仪上有一灵敏的络合吸附波。波的峰电位为-0.59V(SCE)。波高与浓度在3.1×10-8~1.6×10-6mol/L范围内的铜(Ⅱ)成正比,且选择性校好。应用循环伏安、脉冲极谱等方法研究了该极谱波的性质,结果表明该极谱波属于反应物弱吸附的络合吸附波。  相似文献   

18.
镓-水杨基荧光酮伏安络合吸附波的研究   总被引:2,自引:0,他引:2  
在pH为3.0的0.2mol/L邻苯二甲酸氢钾-HCI和5.0×10-6mol/L水杨基荧光酮底液中,线性扫描可得灵敏的Ga-SAF络合物吸附波,峰电位为-0.93V(vsSCE).镓在7.5×10-9~3.8×10-7mol/L浓度范围内与峰高成正比关系.  相似文献   

19.
镍(Ⅱ)-硫代氨基脲体系的络合吸附波   总被引:1,自引:0,他引:1  
利用Ni(Ⅱ)的络合吸附波测定微量镍,文献曾提出若干体系,但 Ni(Ⅱ)-硫代氨基脲(TSC)体系的络合吸附波尚未见报导。本文对该体系采用单扫示波极谱仪进行了试验,获得了灵敏的极谱波,并用多种方法探讨了该体系的机理,认为该极谱波是具有络合吸附波性质的催化前波。  相似文献   

20.
超微量铂丶铑连续催化极谱测定及其催化波机理的探讨   总被引:3,自引:0,他引:3  
舒柏崇  郑日云 《化学学报》1983,41(5):418-424
For simultaneous determination of ultramicro amounts of platinum and rhodium the optimum condition has been described as 1.5N H2SO4-1.2% NH4Cl-0.0012M (CH2)6N4-0.003% N2H4XH2SO4. Both platinum and rhodium produce hydrogen catalytic waves with peak potential at-1.03 V and - 1.27 V (vs. S. C. E.) and the peak height of differential wave in single-sweep polarograph is directly proportional to the concentration of the metals in the range from 0.05 ppb to 1.0 ppb for platinum and from 0.0025 ppb to 0.1ppb for rhodium, respectively. The influence of other platinum group metals and some base metals on the height of catalytic waves has been examined. It has been shown that the method is very selective. It is applied even at 200:1 or at 1:10 (Pt:Rh). The mechanism of the catalytic waves has been discussed. The catalytic waves of both platinum and rhodium are due to "surface catalytic wave of hydrogen". The wave of rhodium can be attributed to catalytic discharge of hydrogen ion by the complex (Rh(CH2O)2Cl4)-. One of the ligands, formaldehyde, is the product of hydrolysis of hexamethylenetetramine. The wave of plainum can be attributed to catalytic discharge of hydrogen ion by the complex (PtACl5)-, where a denotes intermediate product (a substance containing CH2=N group) formed during the hydrolysis of hexamethylenetetramine. The role of hydrazine sulfate in catalytic system has been shown. Hydzazine can react with formaldehyde to from (CH2=N)2 which promotes the growth of platinum catalytic wave and in this way the concentration of formaldehyde in the system can be controlled.  相似文献   

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