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1.
高效毛细管电泳柱端安培检测异丙嗪   总被引:4,自引:0,他引:4  
辛慧君  刘志明 《分析化学》1997,25(5):555-558
本文用高效毛细管区带电泳柱端安培检测了抗组胺药物特异丙嗪。讨论了缓冲溶液浓度,pH值对柱效的影响,为提高检测的重现性考察了电极的电化学处理条件。在优化的实验条件下,异丙嗪的线性范围为1.×10^-7-1×10^-4mol/L,检测下限为3.5×10^-8mol/L,分离并检测了尿样中的1×10^-7mol/L的异丙嗪。  相似文献   

2.
毛细管区带电泳柱端安培检测抗癌药物巯嘌呤   总被引:4,自引:0,他引:4  
王晓清  由天艳  杨秀荣  汪尔康 《分析化学》1999,27(10):1141-1145
报道了一种高效快速检测抗癌药物巯嘌呤的方法-毛细管区带电泳柱端安培检测。考察了巯嘌呤的电化学行为。在最佳操作条件下,获得此药物的检测限为1×10^-7mol/L;线性赤5×10^-4-5×10^-6mol/;相关系数为0.995,重现性良好。并用该法检测了人尿样及牛血清蛋白中的巯嘌呤。  相似文献   

3.
含有吸附络合物溶液的倒数示波计时电位法的应用   总被引:3,自引:0,他引:3  
Pb(Ⅱ)在0.2%乙二胺-5×10^-3mol·L^-1HOx-0.3mol·L^-1KOH溶液中,有良好的全数示波图,其峰电位Ep=-1.05(vs.SCE),峰高与Pb^2+溶度在4.0×10^-7~2.0×10^-5mol·L^-1内成正比,检测下限可达2.0×10^-7mol·L^-1。本实验采用倒数示波计时电位法对铝合金“A”中铅进行了测定,并直接通过示波图,对络合物的吸附属于性进行了  相似文献   

4.
叶建农  赵学伟 《分析化学》1997,25(3):322-325
本文利用自制的毛细管电泳-电化学安培检测装置,以钴钛菁碳糊修饰电极为工作电极。在中性磷酸体系缓冲溶液中,对四种羟胺和巯基类化合物的混合物进行了分离和测定,检测下限羟胺类化合物为5.0×10^-6mol/L巯基类化合物为1.0×10^-5mol/L。对  相似文献   

5.
光谱电化学法测定水果中抗坏血酸的研究   总被引:7,自引:2,他引:7  
本文采用平行入射式光谱电化学装置,对水果中的抗坏血酸进行测定并寻找了最佳的测定条件。方法简便快捷,可消除背景干扰。线性范围1.0×10^-5-1.0×10^-4mol/L,检测下降为4.0×10^-6mol/L,回收率高,结果满意。  相似文献   

6.
头孢噻肟钠的降解及其产物伏安行为的研究   总被引:18,自引:1,他引:18  
头孢噻肟钠在NaOH溶液中降解后,于0.1mol/LNaOH中得一灵敏的吸附伏安原峰,Ep=-0.78V(νsAg/AgCl),ip与头孢噻肟钠浓度在1.0×10^-^9-1.0×10^-^8,1.0×10^-^8-1.0×10^-^7,1.0×10^-^7-1.0×10^-^6mol/L范围内呈线性关系,检出限为5.0×10^-^1^0mol/L。用多种电化学手段研究其降解产物的伏安行为,测定了  相似文献   

7.
本文研究了吐温40-KOH-H2O2-Ir化学发光新体系,采用流动注射进样技术,建立了测定铱的新的化学发光分析法,检测限为1.1×10^-13g/L;线性范围为每mL1.0×10^-9-1.0×10^-5g。经离子交换分离Au和Os离子后,测定贵金属冶金物料中微量铱,结果满意。  相似文献   

8.
本采用装有Jones柱的流动注射系统,研究了钒(Ⅱ)-光泽精体系的化学发光反应。在此基础上建立了痕量钒测定的新方法。方法的检出限3×10^-10g·mL^-1;对于1.0×10^-7g·mL^-1钒标准溶液测定的相对标准偏差为2%(n=11);线性范围1.0×10^-9 ̄9.0×10^-5g·mL^-1,相关系数大于0.9980。该方法已用于水样中痕量钒的测定。对于反应机理,本也进行了探讨。  相似文献   

9.
李怀娜  慈云祥 《分析化学》1997,25(6):679-682
采用流动注射法研究了巯基化合物-铈(Ⅳ)-氢化可的松(HCRs)体系的化学发光行为,对影响化学发光强度的诸因素进行试验和探讨,建立了流动注射化学发光法检测谷胱甘肽(GSH),半胱氨酸(Cys)等含巯基化合物的新方法。检测GSH和Cys和线性范围分别为2.0×10^-6 ̄10.0×10^-5mol/L和1.0×10^-6mol/L ̄10.0×10^-5mol/L;检测限分别为2.0×10^-7mol  相似文献   

10.
乳酸环丙沙星单扫描示波极谱法研究   总被引:3,自引:0,他引:3  
研究了乳酸环丙沙星的极谱伏安行为,在pH=8.3的0.02mol/L,NH4Cl-NH3.H2O底液中,乳酸环丙沙星能产生1个灵敏的还原峰,峰电位为-1.61V,其导数峰高与浓度在3.9×10^-8~1.8×10^-6mol/L和1.8×10^6~1.1×10^-5mol/L范围内呈现良好的线性关系,相关系数r=0.9997,检测下限为2.5×10^-8mol/L,用于乳酸环丙沙星注射液的测定,相  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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