左旋氧氟沙星的荧光光谱法研究

提出了一种测定左旋氧氟沙星（LEV）的荧光光谱新方法。该法基于电子受体氯冉酸（CL）和2,3-二氰-5,6-二氯-1,4-对苯醌（DDQ）与电子给体左旋氧氟沙星之间的荷移反应,显示这两种受体能强烈增敏LEV的荧光强度。对影响反应的不同变量和参数进行了研究,建立了两种荧光光谱法测定LEV的新体系：（1）CL体系,线性范围为0．06～3．6μg／mL,检出限为0．02μg／mL;（2）DDQ体系,线性范围为0．12～2．2μg／mL,检出限为0．04μg／mL。所提方法已用于制剂中左旋氧氟沙星含量的测定,回收率分别为99．72％～99．36％和99．36％～98．86％。     

诺氟沙星荷移络合物的荧光特性和应用

研究了电子受体四氯对苯醌(TCBQ)和2,3二氰5,6二氯1,4对苯醌(DDQ)与电子给体诺氟沙星之间的荷移反应。实验发现,诺氟沙星与以上两种电子受体可生成稳定的nπ络合物,其荧光强度较之诺氟沙星分别增强了12和17倍。据此建立了两种基于荷移反应简便可靠地测定诺氟沙星的荧光光谱新方法。TCBQ法和DDQ法测定诺氟沙星的浓度分别为0.02~1.2和0.14~2.8mg/L时,荧光强度与质量浓度呈良好的线性关系。该方法已成功地用于药物制剂中诺氟沙星含量的测定,其回收率(%)分别为98.87±142~99.63±1.26和98.49±1.46~99.21±1.62。本方法也可用于生物体液中诺氟沙星的测定。     

荷移荧光光谱法测定阿米卡星

建立了测定痕量阿米卡星制剂的新方法。研究了阿米卡星(AK)与电子受体2,3-二氰-5,6-二氯-1,4-对苯醌(DDQ)之间的荷移反应。在甲醇中,阿米卡星与DDQ在室温(30℃)下可迅速形成荷移络合物,其荧光强度较阿米卡星显著增强,最大激发和发射波长分别红移38 nm和86 nm。阿米卡星含量在0.1~1.8×10-6mol/L范围内与其荧光强度呈良好的线性关系,相关系数r为0.9992,检出限为0.0244 mg/L。本法用于实际样品分析,回收率为96.1%~103%,相对标准偏差(RSD)为1.2%~1.7%。     

环丙沙星荷移反应及荧光光谱性质研究

研究了环丙沙星（CPFX）与电子受体2，3－二氰－5，6－二氯－1，4对苯酯（DDQ）之间的荷移反应。实验结果表明：DDQ与CPFX的荷移反应需在丙酮－甲醇（1：4）介质中进行。两者于40℃水浴中恒温30min即可形成1：1络合物，其荧光发射较CPFX有显著的增强。在0．107．2mg/L浓度范围内，荧光强度与质量浓度呈良好线性关系；其检出限为0．1mg/L。本方法用于片剂中环丙沙星的含量测定，其回收率为96．6％－100．2％；标准偏差为1．3％－2．6％。     

精氨酸与2,3-二氯-5,6-二氰-1,4-苯醌的荷移反应研究

用分光光度法研究了精氨酸与2,3-二氯-5,6-二氰-1,4-苯醌(DDQ)的荷移反应。实验表明,在硼砂溶液中,精氢酸与DDQ在室温下反应30min可获得稳定的络合物,其组成比为2∶1,λmax=342nm,表观摩尔吸光系数ε=1.65×104 L.mol-1.cm-1,线性范围为2～30μg/mL。应用拟定的方法测定了盐酸精氨酸注射液的含量,结果与文献方法一致,回收率在97.2%～98.1%之间,相对标准偏差小于3.1%。     

阿奇霉素与百里香酚蓝的荷移反应及其在药物测定中的应用

基于阿奇霉素与百里香酚蓝在无水乙醇介质中可以发生荷移反应,建立了测定阿奇霉素的新方法.在无水乙醇溶剂中,阿奇霉素与百里香酚蓝发生荷移反应,其荷移络合物在550 nm处有最大吸收峰.由吸光度测定阿奇霉素的含量.表观摩尔吸光系数ε=8.5×103 L·mol-1·cm-1,络合物组成比为1:2.稳定常数为1.0×1010,阿奇霉素质量浓度在2.52～21.0μg/mL内与吸光度呈良好的线性关系,线性回归方程为A=-0.02242+0..167ρ(μg/mL),线性相关系数R=0.9994,检出限(3ρ/k)为2.52μg/mL,相对标准偏差为1.4%.     

荷移荧光光谱法测定牛奶中苄青霉素残留

采用荧光光谱法研究了电子供体苄青霉素降解产物与电子受体四氯苯醌(TCBQ)之间的荷移反应,结果表明TCBQ与苄青霉素的酸性降解产物在甲醇-水介质中易发生荷移反应,生成稳定的络合物,其荧光强度较苄青霉素降解产物本身有了显著的增强。据此建立一种测定苄青霉素的新方法,在最佳条件下,苄青霉素浓度在0.30～8.0 mg/L范围...     

以碘为受体的荷移络合物的荧光光谱研究及应用

采用荧光光谱法研究了诺氟沙星与碘形成荷移络合物的荧光性质,发现碘对诺氟沙星有强烈的荧光增敏效应。据此,建立了一种高灵敏的测定诺氟沙星的荷移荧光光谱新方法。优化了影响反应的不同变量和参数,在最佳实验条件下,方法线性范围为0.04~1.5μg/mL,检出限为0.01μg/mL。该方法用于药物制剂中诺氟沙星含量的测定,其回收率为98.09%~99.97%。     

阿米卡星荷移反应及荧光光谱性质研究

研究了阿米卡星与电子受体氯醌酸之间的荷移反应。实验表明:在无水乙醇中,阿米卡星与氯醌酸在室温(25±5℃)下可迅速形成紫色的荷移络合物,此络合物常温下可稳定50 min,其荧光强度较阿米卡星显著增强,最大激发和发射波长分别红移135 nm和53 nm。阿米卡星含量在80~800μg/L范围内与其荧光强度呈良好的线性关系,相关系数r为0.9994,检出限为28.9μg/L。本法用于实际样品分析,回收率为95.5%~101.4%,相对标准偏差(RSD)为0.47%。     

琥乙红霉素与甲基红的荷移反应研究

研究了电子给体琥乙红霉素与电子受体甲基红之间的电荷转移反应,确定了反应的最佳条件,建立了一种快速、简便测定琥乙红霉素的荷移分光光度法。结果表明:琥乙红霉素与甲基红在乙醇-水介质中即可生成稳定的1∶1络合物,该络合物的最大吸收波长为421nm,表观摩尔吸光系数和稳定常数分别为1.48×104 L·mol-1·cm-1和1.445×105。琥乙红霉素浓度在2.0~84.0μg/mL范围内符合比耳定律,线性相关系数为0.9991,检出限为1.06μg/mL。该方法用于测定药物制剂中琥乙红霉素的含量,加标回收率为98.2%~101.6%。     

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.     

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。     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

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。     

氯氧化镁生成热的研究

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^-。     

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.

     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

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.     

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。