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1.
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   

2.
在0.01mol/LNH.H2O-NH4Cl和3.0×10^-5mol/L安息香缩氨基硫脲体系中,钴产生一灵敏的还原波,其峰电位是-0.94V(vs.SCE),峰电流与钴的浓度在2.0×10-8-1.0×10^-6mol/L范围内成直线关系,检测限为5.0×10^-9mol/L,该法测定水中痕量钴结果令人满意。  相似文献   

3.
环丙沙星的极谱催化波研究   总被引:1,自引:0,他引:1  
在0.1mol/LKH2PO4-NaOH(ph6.8±0.2)的缓冲溶液中,在眄环丙沙星产生一极谱催化波,其二阶导阴极催化波峰高与环丙沙星浓度在9.85×10^-7 ̄1.97×10^-5mol/L范围呈良好的线性关系,相关系数为0.9999。该法已用于测定盐酸环丙沙星片中的环丙沙星的含量,结果满意。实验证明其电极过程 吸附催化波的特征。  相似文献   

4.
杨志 《分析化学》1998,26(5):542-544
在金电极上,用电化学方法将单缺位Dawson型磷钨杂多酸盐a2-K10P2W17O6115H2O的阴离子(P2W17)掺杂到聚吡咯(PPy)薄膜中,制成PPy/P2W17/Au的H2O2传感器。研究了它对 H2O2电还原过程的催化机理.其 ipe与 CH2O2在 6.0× 10-5~8. 8×10-4 mol/L和8.8×10-4~6.0×10-3mol/L范围内呈良好的线性关系,检测下限为4.0×10-5mol/L。用于模拟水样中H2O2的测定,结果较满意.  相似文献   

5.
测定超氧化物歧化酶活性的一种新的极谱分析方法   总被引:3,自引:0,他引:3  
杨天鸣  黎瑞珍 《分析化学》1998,26(11):1342-1345
报道一种测定超氧化物歧化酶活生的新极谱分析方法,在0.125mol/LNH3.H2O-0.75MOL/l nh4cL-2.5%,Na2SO3-0.5%,吐温-80-的介质中,SOD在-0.52V处产生一氧极谱催化波。SOD在1.0×10^3U/L-4.0×10^3U/L的活性含量范围内与催化电流呈线性关系,检出限为8.0×10^2U/L。  相似文献   

6.
头孢哌酮钠的伏发行为及其应用研究   总被引:2,自引:0,他引:2  
头孢哌酮钠在0.05mol/L H2SO4溶液中,形成一良好的示波极谱导数峰。峰电位为-0.82V(vs.SCE)。峰电流与头孢哌酮钠的浓度在1.0×10^-7-2.0×10^6mol/L范围内成线性关系。检出限为5.0×10^-8mol/L。回收率在94.0%-102.0%之间。并用于尿样的测定,得到满意的结果。  相似文献   

7.
熊国华  刘虹 《分析化学》1994,22(11):1141-1144
本研究了Mn^2+和Co^2+对7-(8-羟基-3,6-二磺基萘偶氮)-8-羟基喹啉-5-磺酸-硼砂反应体系的混合荧光增敏作用。实验条件下,荧光增敏强度满足线性加和关系的范围是:Mn^2+浓度0 ̄2.9×10^-7mol/L;Co^2+浓度0 ̄8.8~10^-7mol/L;总浓度不超过1.0×10^-6mol/L。检出限量为Mn^2+4.5×10^-9mol/L和Co^2+1.4×10^-8mo  相似文献   

8.
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   

9.
流动注射化学发光抑制法测定抗坏血酸   总被引:22,自引:0,他引:22  
李峰  张文艳  朱果逸 《分析化学》2000,28(12):1523-1526
基于抗坏血酸对Luminol-KIO4-H2O2体系化学发光反应的抑制作用,建立了化学发光抑制快速测定抗坏血酸的新方法。该方法线性范围为1.0*10^-7-1.0*10^-5mol/L,检出限为6.0*10^-8mol/L,对8.0*10^-7mol/L抗坏血酸11次平行测定的相对标准偏差为1.0%。用于维生素C片剂及注射液中抗坏血酸含量的测定,结果令人满意。  相似文献   

10.
氨基萘磺酸盐无保护流体室温磷光的取代基位置效应   总被引:1,自引:0,他引:1  
牟兰  陈小康 《分析化学》1999,27(5):509-512
以TINO3作重原子微扰剂,Na2SO3作化学除氧剂,在无需加入任何保护介质条件下,仅需仪器光源适当照射,1-氨基4-萘磺酸盐、1-氨基5-萘磺酸盐、2-氨基1-萘磺酸盐水溶液均能产生强而稳定的室温磷光信号(RTP)。3种氨基萘磺酸盐浓度分别在4.0×10^-8 ̄1.2×10^-5mol/L;1.2×10^-6 ̄1.6×10^-5mol/L;1.6×10^-7 ̄8.0×10^-6和8.0×10^-  相似文献   

11.
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   

12.
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   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

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20.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

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