气相色谱法快速同时测定室内装饰装修材料胶黏剂中的苯、甲苯、二甲苯的含量

建立了快速、同时测定室内装饰装修材料胶黏剂中苯、甲苯、二甲苯含量的气相色谱检测法.样品用乙酸乙酯溶解处理后,用改性的聚乙二醇(FFAP)毛细管色谱柱分离,氢火焰离子化检测器检测,外标法定量.胶粘剂中苯、甲苯、二甲苯的浓度分别在8.58～171.40μg/mL、9.04～180.62μg/mL、8.80～175.92μg...     

用于快速评价和筛选离子液体的比较色谱法

建立了一种快速评价和筛选离子液体的比较气相色谱方法,以各离子液体系列中研究最多的离子液体为参比固定液,装填成参考柱,以新设计合成的离子液体为样品固定液,装填成样品柱.以正己烷、乙酸乙酯、苯、2-戊酮、吡啶、丁醇和1-硝基甲烷7种溶剂作为探针分子,采用调整保留时间和不对称因子为考察指标,能够有效地筛选出满足应用的离子液体.     

几种适宜于稗草中脱落酸薄层色谱分离和鉴定的展开剂

(二)样品预处理 稗草样品经溶剂萃取浓缩后,上1.5cm×20cm硅胶H干柱,以苯-乙酸乙酯-乙酸(50∶3∶1)混合液洗脱。洗脱液分步收集,经以苯-乙酸乙酯-乙酸(30∶5∶2)为展开剂的高效薄层检测,254nm紫外光显迹检查,合并富含R_f≈0.74斑点,对白菜种子萌发及幼根生长具有抑制活     

修正液中苯的测定

乙酸乙酯为溶剂对修正液样品进行预处理,并用气相色谱法测定样品中苯的含量.该方法操作方便,分析速度快,结果准确.     

溶剂型涂料中16种有害物质的气相色谱-质谱同时检测方法

建立了溶剂型涂料中16种有害物质(甲醇、卤代烃、苯系物和游离二异氰酸酯)的GC-MS同时检测方法,研究了乙酸乙酯、正己烷、四氢呋喃和乙腈对各有害物质的提取和分离效果,并对样品前处理和色谱条件进行了优化.样品中加入2-溴丙烷和1,2,4-三氯苯作内标,用乙腈超声萃取并经有机膜过滤后,用.GC-MS进行测定,内标法定量.结...     

气相色谱法同时测定醇酸类油漆中苯系物

用乙酸乙酯稀释油漆样品,在汽化温度下直接进样,采用PEG-20M毛细管柱,FID为检测器,用气相色谱法测定了醇酸类油漆中的苯、甲苯和二甲苯,内标法定量.测定结果的回收率为97.21%～100.66%,相对标准偏差不大于1.3%(n=4).     

乙醇合成丁二烯反应中液相产物的气相色谱分析

进行了用甘油柱和硅油柱串联以分离乙醇合成丁二烯液相产物中的副产物的研究.首先在甘油柱中将样品内大量乙醇和水同其他组分分离,井用反吹法将乙醇和水冲出柱外,其他组分进入硅油柱进一步被分离.通过颜色反应、化学处理和假设组分三种方法,鉴定出副产物中含有乙醛、乙醚、丙酮、戊醛、丁醛和乙酸乙酯等化合物;对前四种物质还进行了定量分析.     

高效液相色谱法测定虎杖中白藜芦醇、白藜芦醇苷和游离大黄素

用高效液相色谱法同时测定虎杖中白藜芦醇、白藜芦醇苷和游离大黄素含量.色谱柱为Waters Symmetry C18柱(3.9 mm×150 mm,5μm),流动相为0.015 mol-1 H3PO4-甲醇,流速为0.5 mL·min-1,检测波长为284nm.样品采用乙醇-水(1 1)溶液和乙酸乙酯提取.江西产虎杖样品中白藜芦醇、白藜芦醇苷和游离大黄素的回收率分别为97.9%,96.1%,95.6%,相对标准偏差小于5%.     

高效液相色谱法测定乳及乳制品中硫苯唑残留量

建立了高效液相色谱测定乳及乳制品中硫苯唑残留量的检验方法,用氢氧化钾皂化试样中脂肪,用乙酸乙酯提取硫苯唑,在45℃以下浓缩近干,定容至1.0 mL.在高效液相色谱测定中用ODS C18柱为固定相,甲醇和水(70+30)混合溶液作为流动相.在保留时间为4.43 min时用二极管阵列检测器检测硫苯唑的色谱峰,外标法定量.检出限(3S/N)为0.02 mg·kg-1,回收率在94.5%～98.6%之间,相对标准偏差(n=10)在1.3%～4.2%之间.     

GC/MS测定锅巴中丙烯酰胺含量

建立了一种测定市售锅巴中的丙烯酰胺含量的方法.该法样品前处理不必经过溴化衍生,样品脱脂后用水提取丙烯酰胺,提取液过活性炭柱,再用乙酸乙酯将活性炭柱中吸附的丙烯酰胺洗脱.洗脱液浓缩后经气相色谱-质谱(GC-MS)定量分析,检测限为0.06 mg/kg,适合测定市售锅巴中的丙烯酰胺的含量.还考察了丙烯酰胺在水的固液两相中的分配比.     

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。     

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.

     

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。     

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。     

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^-。     

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.     

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.     

NiY分子筛表面酸性影响其选择性吸附脱硫性能的机理研究

采用原位红外光谱技术,以噻吩、环己烯和苯为模型探针分子,分别考察单一烃分子在NiY分子筛上的吸附与反应行为以及噻吩与烯烃、芳烃间的竞争吸附和催化反应行为。单一探针分子吸附研究发现,NiY分子筛中与Ni物种相关的Lewis(L)酸位是噻吩的选择性吸附活性位;噻吩和环己烯在NiY分子筛中Brnsted(B)酸位上发生的质子化和低聚反应明显弱于HY分子筛。双探针分子竞争吸附研究发现,环己烯二聚体在NiY中强B酸位上的强化学吸附与噻吩存在显著的竞争吸附行为。另外,苯和噻吩在NiY上的竞争吸附现象在373K时明显减弱。由此,在选择性吸附脱硫过程中,减少吸附剂表面B酸中心可降低烯烃对噻吩的竞争吸附,另外适当提高吸附体系的温度可以有效避免芳烃对噻吩的竞争吸附。