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1.
氧氟沙星的单扫描示波极谱分析 总被引:8,自引:0,他引:8
报道了一种灵敏的氧氟沙星测定方法-一阶导数单扫示波极谱分析,同时研究了它的极谱波性质和电极反应机理,在pH6.0的KH2PO4-Na2HPO4(PBS)底液中,氧氟沙星产生一个灵敏的还原峰,Ep=-1.55V(vs.SCE),其导数峰高与浓度在1.0×10^-5~4.6×10^-7mol/L范围内呈良好的线性关系,相关系数r=0.9996,检测下限为2.4×10^-7mol/L,可用于氧氟沙星片剂 相似文献
2.
在0.05mol/L HAc-0.10 mol/L NaAc(pH4.96)底液中,司巴丁在单扫示波极谱上有一灵敏的催化氢波。导数波峰电位于-1.65V(vs.SCE)。司巴丁浓度在4×10^-7~×10^-6mol/L范围内与峰高成线性关系。检测下限为6×10^-8mol/L。本对于极谱波的性质及电极过程机理进行了较详细的探讨。 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.
研究了6-硝基喹啉在滴汞电极上的电极过程并建立了它的单扫示波极谱测定。在0.10mol/LNaCl底液中,6-硝基喹啉的二阶导数阴极波峰电流i"p(E"p=-0.66VvsSCE)浓度在1.0×10^-7-2.5×10^-5mol/L范围内有良好线性关系,检出限为4.2×10^-8mol/L,RSD=1。7%(n=6)。此外还考察了多种人体内常见微量物质及表面活性剂对i"p的影响。 相似文献
5.
鸟嘌呤—铜配合物在汞电极表面上的电吸附性的研究 总被引:1,自引:0,他引:1
在0.02mol/L NaHCO3-0.05mol/La2SO4介质中、用极谱法和伏安法研究表明,铜-乌嘌呤配合物在汞电极表面上的吸附服从Langmuir吸附,测得其饱和吸附量Γm=1.1×10^-10mol/cm^2,吸附系数β=4.7×10^4,吸咐自由能△G°=-36.6kJ/mol。在8×10^-6mol/L Cu^2+离子存在下,可用示差脉冲阴极吸附溶出法测定8×10^-10~1×10^ 相似文献
6.
铜—腺嘌呤络合物吸附波的研究 总被引:1,自引:0,他引:1
了在0.08mol/LNaAc~0.02mol/LHAc缓冲溶液铜与腺嘌呤(Ade)络合物的极谱行为,结果表明,扫描电压为-0.2V~-0.7V时铜-腺嘌呤络合物在单扫示波极谱上有一络合物吸附波,其一阶导数峰电位主-0.4V(vs.SCE),腺嘌呤浓度在1.0×10^-6~1.0×10^-5mol/L范围内与一阶导数波高呈良好的线性关系,检出限为1.0×10^-7mol/L,实验证明,该峰具有吸附 相似文献
7.
碘酸钾存在下极谱催化波法测定陈皮甙 总被引:2,自引:0,他引:2
基于陈皮甙在KIO3存在下产生的极谱催化波,拟定了测定陈皮甙的新方法。在 0.55 mol/L HAc-0.01mol/L NaAc(pH 4.00±0.05)-1.0×10~(-3)mol/L KIO3缓冲溶液中,陈皮甙催化波的峰电位为-1.35 V(vs,SCE),它的一阶导数峰峰电流与陈皮甙浓度在2.6 × 10~(-7)~2.6 × 10~(-6)mol/L范围内呈线性关系(r=0.9970,n=6)。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。 相似文献
8.
吡哆醛的电化学行为研究 总被引:2,自引:0,他引:2
用单扫示波极谱法,吡哆醛在0.2mol/LKCl+0.02mol/L naOH底液中,产生一良好的寺阶导数峰,EP=-1.30±0.01V(SCE),其峰高与浓度在2×10^-7-2×10^-4mol/L范围内成线性关系,检出限为1×10^-7mol/L实验证明,其电极过程为伴有微弱吸附性质的的可逆扩散过程(n=2),不在弱酸性和中性介质中时,吡哆醛的电极过程为前行动力学过程,其电极反应机理为伴有 相似文献
9.
本文比较了Mo(Ⅵ)-1-(2-吡啶基偶氮)-2-萘酚(PAN)与Mo(Ⅵ)-4(2-吡啶基偶氮)间苯二酚(PAR)的极谱性质,讨论它们在作为吸附波试剂时的优缺点,以求得在选择络合剂时的感性和理性认识.本文还报道了Mo(Ⅵ)-PAN-KBrO3吸附催化波体系,最佳实验条件,0.1mol/LHAc--NaAc,pH=4.6,0.01mol/LKBrO3,2.5×10-5mol/LPAN.峰电位为-0.71V(vs.SCE),检出限1×10-9mol/L,线性范围0~6×10-7mol/L 相似文献
10.
大黄酚在0.15mol/L HAc-NaAc(pH4.9)底液中,出现一灵敏的示波极谱导数峰,峰电位为-0.45V(vs,SCE),峰电流与大黄酚浓度在2.0×10^-7-5.0×10^-6mol/L范围内成线性关系,检测限为2.0×10^-6mol/L。用于生药大黄中大黄酚的测定,回收率为92.4%-108.4%。用多种电化学手段研究体系的电化学行为,测得电极反应电子数n=2。体系具有吸附性,并 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.
Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
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
13.
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
14.
Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
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
15.
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
16.
N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
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
17.
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
18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative. 相似文献
20.
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