一氧化氮在水杨醛谷氨酸合镍修饰碳黑微电极上的电催化氧化

制备了水杨醛谷氨酸合镍修饰碳黑微电极,试验了修饰电极对一氧化氮的电催化氧化性能。试验结果表明,在pH 6.8的磷酸盐中,一氧化氮在该电极上的线性范围为4.0×10-8~1.0×10-5mol.L-1;检出限(3σ)为1.0×10-8mol.L-1。将此电极用于3种模拟样品的分析,并在此基础作回收率试验,测得RSD(n=8)值在1.9%~2.8%之间,回收率在97%~105%之间。在一氧化氮浓度1.0×10-6mol.L-1的水平上进行精密度试验,测得RSD(n=10)为2.2%。     

基于巯基丁二酰肼铜（Ⅱ）单层修饰电极的HIV-p24电化学免疫传感器

研制了基于巯基丁二酰肼铜(Ⅱ)(CuL)单层修饰金电极(Au|CuL)测定艾滋病人血清中HIV核心抗原p24水平的免疫传感器.该传感器通过将CuL直接自组装到金电极表面制备而成.CuL对H2O2的还原具有催化作用,可作为p24抗体(anti p24)上标记的辣根过氧化物酶(HRP)与电极之间电子传递媒介体.结合竞争性免疫分析,HRP-anti p24抗体(HRP-anti p24)与待测p24反应生成的免疫结合物游离在反应池中,通过测定在免疫结合物上HRP作用下电极表面CuL对H2O2催化增强电流,采用示差脉冲伏安法(DPV)直接获得待测抗原的含量.该免疫传感器的测定无需分离和洗涤步骤,温育时间短,为艾滋病诊断提供了一种新的方法.     

流动注射抑制化学发光法测定盐酸环丙沙星

在碱性介质中,环丙沙星对鲁米诺-KIO4-Co2 反应体系产生的化学发光明显地受到抑制,且化学发光强度的抑制强度与环丙沙星的浓度成正比关系.基于上述现象,提出了环丙沙星的流动注射-化学发光测定法.环丙沙星的质量浓度在3.0×10-7～1.0×10-5g·L-1之间成线性关系,检出限为2.0×10-7g·L-1.对浓度水平为1.0×10-6g·L-1的盐酸环丙沙星进行11次平行测定,得到RSD(n=11)值为2.7%.应用此方法分析了环丙沙星药片,所得结果与按中国药典方法所得测定值保持一致,回收率试验的结果在98.5%～101.2%之间.     

L-半胱胺尾式卟啉铜(II)修饰金电极检测苯酚

将制备的L-半胱胺卟啉铜(II)(CuL)配合物自组装在Au电极表面,获得电化学苯酚传感器(CuL/Au)。在pH 7.0的磷酸盐缓冲液(PBS)中于-0.4 V~0.5 V(vs.SCE)电位范围内有一对氧化还原峰,峰电位分别为Epa=0.09 V和Epc=-0.06 V。实验结果表明CuL能够催化氧化苯酚,通过产物在电位0.1 V下的电化学响应对苯酚进行测定。该电极对苯酚表现出快速的响应(响应时间<10 s)。传感器对苯酚的测定具有较宽的线性范围(5.0×10-7mol.L-1~2.5×10-4mol.L-1),检出限为2.0×10-7mol.L-1。该电极用于地表水中苯酚含量检测,并与标准方法4-氨基安替比林分光光度法作了对照,结果满意。     

L-半胱胺尾式卟啉铜(Ⅱ)修饰金电极检测苯酚

将制备的L-半胱胺卟啉铜(Ⅱ) (CuL) 配合物自组装在Au电极表面,获得电化学苯酚传感器(CuL/Au).在pH 7.0的磷酸盐缓冲液(PBS)中于-0.4 V～0.5 V (vs. SCE)电位范围内有一对氧化还原峰,峰电位分别为Epa = 0.09 V和Epc = - 0.06 V.实验结果表明CuL能够催化氧化苯酚,通过产物在电位0.1 V下的电化学响应对苯酚进行测定.该电极对苯酚表现出快速的响应(响应时间＜10 s).传感器对苯酚的测定具有较宽的线性范围(5.0×10-7 mol·L-1～2.5×10-4 mol·L-1),检出限为2.0×10-7 mol·L-1.该电极用于地表水中苯酚含量检测,并与标准方法4-氨基安替比林分光光度法作了对照,结果满意.     

顺序注射-氢化物发生-原子荧光光谱法测定从食品接触材料迁移的痕量铅

提出了顺序注射-氢化物发生-原子荧光光谱法测定食品接触材料中铅迁移量的方法。将食品接触材料样品用40g.L-1乙酸溶液浸泡,所得浸泡液稀释十倍以消除基体干扰。将此溶液以1.2%(体积分数)盐酸溶液作载流引入顺序注射分析系统,同时引入7g.L-1硼氢化钠溶液(溶于7g.L-1氢氧化钠溶液中)作还原剂。铅的质量浓度在20.0μg.L-1以内与其荧光强度呈线性关系。方法的检出限(3s)为0.031μg.L-1。以空白食品接触材料为基体,加入铅标准溶液做回收试验,测得回收率在96.6%～101%之间,测定值的相对标准偏差(n=8)在2.2%～4.4%之间。     

氢化物发生-原子荧光光谱法测定环境水样中痕量镉

采用氢化物发生-原子荧光光谱法对环境水样中痕量镉进行测定。对分析的条件进行了试验并予以优化。在0.12 mol.L-1盐酸介质中,以1 mg.L-1钴溶液为信号增感剂,10 g.L-1硫脲溶液作为络合剂,当硼氢化钾质量浓度为30 g.L-1时,镉质量浓度在6.0μg.L-1以内与荧光强度值呈线性关系。对空白溶液进行11次测定,其方法检出限(3s/k)为0.18μg.L-1。此方法应用于环境水样的分析,并在此样品基础上,用标准加入法对方法作回收试验,测得平均回收率为96.3%及101.7%。     

冷原子荧光光谱法测定饮用水中痕量汞

针对测定痕量汞的目标,对AFS-930原子荧光光度计的操作条件作了优化试验;特别在PMT的负高压及原子化温均选用了有利于痕量测定的低值,即依次为270 V及200℃。此外,试样测试溶液的硝酸酸度也用了低值即0.16~0.48 mol.L-1硝酸,试验证明在此酸度条件下,可使测定有良好稳定性和精密度。在最佳工作条件下,汞浓度在0~1.0μg.L-1范围内保持线性关系,相关系数达0.999 9。对三种浓度水平的汞进行精密度试验,测定值的RSD均小于2.14%。此方法的检出限为0.002 0μg.L-1,回收率试验的结果在95.8%至104.4%之间。     

辣根过氧化物酶生物传感器的制备及其应用于过氧化氢的测定

通过将碳纳米管及二氧化钛复合材料(CNT-TiO2)修饰于金电极表面,并借其对辣根过氧化物酶的静电吸附和对羧酸基的高反应特性,使辣根过氧化物酶(HRP)固定在CNT-TiO2表面,制成了辣根过氧化物酶生物传感器(HRP-CNT-TiO2)。对此修饰电极在磷酸盐缓冲介质(pH7.2)中的电催化性质及其电催化反应的最佳条件作了研究。试验结果表明,此电极对过氧化氢有很好的电催化特性,且发现当过氧化氢的浓度在4.2×10-7~3.2×10-4mol.L-1之间与ΔI之间呈线性关系,检出限(S/N=3)为7.2×10-8mol.L-1。为试验方法的精密度,对过氧化氢的浓度水平为5×10-5mol.L-1的条件下进行了8次测定,结果的RSD值为4.5%。     

盐酸浸提-氢化物发生-原子荧光光谱法测定中成药中痕量无机砷

中成药在6 tooL·L-1的盐酸溶液中,经加热后,无机砷以氯化物的形式被提取,用氢化物发生-原子荧光光谱法测定痕量无机砷.砷浓度在50μg·L-1以内与其峰面积之间保持线性关系(γ=0.999 6),方法的检出限为0.34μg·L-1,分析了中成药样品,结果的RSD值小于4%,回收率试验结果在92.6%～104.0%之间.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

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.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

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.

     

非那雄胺合成工艺改进

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。     

Synthesis of phenolic components of Grains of Paradise

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.     

恶臭嗅辨实验室建设探讨

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。     

Summary of development of the theory of stability of colloids and thin films

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.     

Study of hydration of two cements of different strengths

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, M_o, 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 600-700^oC. 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.     

解决能源问题的新途径——光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。     

黄酮化合物的合成研究进展

黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.