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1.
依诺沙星在混合粘合剂碳糊电极上的电化学特性   总被引:3,自引:2,他引:3  
制备了混合粘合剂碳糊电极。在0.015mol/L,磷酸-0.10mol/LKCl溶液中,依诺沙星在该电极上于-1.26V处产生一灵敏的阴极溶出伏安峰。在-0.90V富集90s后,依诺沙星的线性范围为3.1×10^-7-1.2×10^-5mol/L,检测下限为9.42×10^-8mol/L,所提出的方法用于尿液和血清中依诺沙星测定,回收率在96%-103%之间。  相似文献   

2.
魏显有 《分析化学》1995,23(5):502-505
在HCl-NaAc介质(pH2.5)中,用单扫示波极谱法可获得高灵敏的In(Ⅲ)-2-巯基苯骈噻唑(MBT)-7-碘-8-羟基喹啉-5-磺酸(Ferron)三元络合物吸附波,峰电位在一-0.64V(vs.SCE),峰电流与铟浓度在7.0×10^-10mol/L~8.8×10^-7mol/L之间呈线性关系,检出限可达3.0×10^-10mol/L,测得电活性络合物的组成为In(Ⅲ):MBT:1∶1∶  相似文献   

3.
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   

4.
报道了测定痕量镉的一种新方法.在0.01mol/LHAc-0.01mol/LNaAc-1.2×10-5mol/L乙醛酸缩氨基硫脲(GATSC)体系中,Cd-GATSC产生一灵敏的吸附还原波,波的峰电位是-0.43V(vs·SCE),峰电流与镉的浓度在1.0×10-8~8.0×10-7mol/L范围内成直线关系.此法用于测定水中痕量镉,结果令人满意。  相似文献   

5.
托美汀的吸附伏安法研究   总被引:2,自引:0,他引:2  
谭学才  李耀华 《分析化学》1998,26(4):439-442
在0.2mol/L NH3-NH4Cl底液中,托美汀在悬汞电极上有一灵敏的还原峰。峰电位为Epc=-1.48V,该峰具有明显的吸附性,峰电流ipc与TOL浓度在4.0×10^-9-7.0×10^-7mol/L范围内呈线性关系;检出限为5.0×10^-10mol/l,用该法测定了片剂TOL的含量,结果良好。  相似文献   

6.
本文提出用丙三醇-液体石腊混合粘合剂碳糊电极阴极溶出伏安法测定氯硝安定。在pH9.5的NH_3-NH_4Cl缓冲溶液中,氯硝安定在碳糊电极上于-0.73V(P_1)和-1.33V(P_2)处产生两个阴极溶出峰,利用P_1峰可测定微量的氯硝安定。在8.0×10 ̄(-8)~1.1×10 ̄(-5)mol/L范围内,波高与浓度线性关系良好,检测T1民达4.0×10,8mol/L。该法用于血清中氯硝安定测定,相对误差在10%以内。  相似文献   

7.
微分吸附计时电位法测定溴莫普林   总被引:1,自引:0,他引:1  
提出一种测定新药溴莫普林(BDP)的微分吸附计时电位法。在Michaclis(MCL)缓冲液中溴莫普林于一1.33V左右产生一灵敏的微分吸附计时电位溶出峰,利用该峰测定BDP的线性范围为2.0×10^-8-3.0×10^-7mol/L,吸附富集3min检测下限为5.0×10^-9mol/L。探讨了影响灵敏度的主要因素,用循环伏安法,脉冲极谱等多种是化学方法研究了该体系的电化学行为和电极机理,认为所  相似文献   

8.
胆绿素的溶出伏安法研究及胆红素的间接测定   总被引:2,自引:0,他引:2  
本对胆绿素的吸附溶出分析法进行了研究,发现胆绿素在Na2HPO4-Na3PO4(0.1mol/L,pH11.5)缓冲溶液中可在-0.83V(vs,SCE)左右产生灵敏的吸附溶出峰,该峰可检测出低至5×10^-9mol/L胆绿素。在通常条件下,通过0.5min预富集后溶出,可使峰高提高约一个数量级。应用此法间接测定了小牛血清中的胆红素含量。  相似文献   

9.
在pH为6.0的B-R缓冲溶液中,丙酸睾丸素于电位-1.4V(vs.SCE)左右处出现一个灵敏的附阴溶出峰。经5min富集后,阴极溶出峰电流与浓度在1.38×10^-^8-7.3×10^-^8mol/L范围内成线笥关系,该方法用于注射液中丙酸睾丸素含量测定,回收率80%-86%。检测下限为4.1×10^-^9mol/L。  相似文献   

10.
李益恒  朱志伟 《分析化学》1995,23(9):1069-1072
本研究了锡(Ⅳ)-3,4-二羟基苯甲酸络合物的相敏交流吸附溶出行为,在PH3.6的甲酸盐缓冲溶液中,该络合物经两步双电子还原在相敏交流伏安图上于-0.33V和-0.49产生两个吸附还原波,第一个波更灵敏,峰电流与锡浓度在1.7×10^-9-2.5×10^-7mol/L范围内呈线性关系,检测限达4×10^-10mol/L。测得络合物组成的1:1。方法已应用于罐头食品中锡的测定。结果满意。  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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