固相萃取-毛细管柱-气相色谱法测定水中11种有机磷农药

提出了固相萃取分离-毛细管柱-气相色谱法测定水中11种有机磷农药的方法。水样经Waters oasis HLB固相萃取小柱分离并净化,甲醇-丙酮(70+30)混合液洗脱。用Varian cp-sil24CB色谱柱(30m×0.25mm,0.25μm)分离,脉冲火焰光度检测器检测。11种有机磷农药的质量浓度均在5.00μg·L-1以内与其峰面积呈线性关系,测定下限(10S/N)在0.03~0.05μg·L-1之间。方法用于地表水样和饮用水样分析,加标回收率在65.7%~124%之间,测定值的相对标准偏差(n=6)在1.8%~9.9%之间。     

固相萃取-在线凝胶渗透色谱-气相色谱-质谱法测定豆芽中53种农药残留量

采用固相萃取-在线凝胶渗透色谱-气相色谱-质谱法测定豆芽中53种农药残留量。豆芽样品以乙酸-乙腈(1+99)混合液提取,固相萃取小柱净化,采用在线凝胶渗透色谱-气相色谱分离,在质谱分析中采用选择离子监测模式。53种农药的质量浓度均在0.01~1.0mg·L-1范围内与其峰面积呈线性关系,方法的检出限在0.1~6.0μg·kg-1之间。在20,50,100μg·kg-1等3个浓度水平进行加标回收试验,回收率在72.3%~104%之间,测定值的相对标准偏差(n=6)在1.6%~6.6%之间。     

大体积固相萃取-气相色谱法测定海水中10种多氯联苯

采用大体积固相萃取-气相色谱法测定海水中10种多氯联苯的含量。海水样品采用大体积样品采样器与聚苯乙烯/二乙烯基苯固相萃取柱进行萃取。萃取流量为5.0mL·min-1,丙酮作为洗脱剂。用Agilent HP-5石英毛细管色谱柱(30m×0.32mm,0.25μm)分离,微池电子捕获检测器检测。10种多氯联苯的质量浓度均在10.0μg·L-1以内与其峰面积呈线性关系,方法的检出限(3S/N)在0.002 3~0.012μg·L-1之间。测定值的相对标准偏差(n=7)在0.9%~1.3%之间,在0.5,1.5,4.0μg·L-1等3个浓度水平进行加标回收试验,回收率在80.7%~127%之间。     

气相色谱-串联质谱法测定烟草中97种农药残留量

利用气相色谱-串联质谱法(GC-MS/MS)检测烟草中97种农药残留。样品以乙腈为溶剂经加速溶剂萃取(ASE),提取液用Carbon-NH2固相萃取小柱净化后,采用VF-5MS色谱柱分离,用电子轰击离子源-多反应监测模式(EI-MRM)检测。97种农药的质量浓度在20~1 000μg·L-1范围内与其峰面积呈线性关系,方法的测定下限(10S/N)在0.02~22.4μg·kg-1之间;在50,100,500μg·kg-1的加标水平下,测得回收率在67.4%~116%之间,测定值的相对标准偏差(n=6)在1.9%~14%之间。     

毛细管气相色谱法测定沉香中20种有机氯农药残留量

应用毛细管气相色谱法测定沉香中20种有机氯农药的残留量。样品以乙酸乙酯提取,提取液用凝胶色谱-固相萃取(GPC-SEP)进行净化。采用DB-1701P石英毛细管色谱柱(30m×0.25mm,0.25μm)分离样品,电子捕获检测器进行检测。20种有机氯农药的线性范围均为1~50μg·L-1,检出限均为0.1μg·kg-1。方法用于沉香样品分析,加标回收率在95.8%~114%之间,测定值的相对标准偏差(n=6)在0.3%~3.8%之间。     

顶空固相微萃取-气相色谱-质谱法测定蔬菜及水果中15种农药残留量

应用顶空固相微萃取-气相色谱-质谱法测定蔬菜及水果中15种农药的残留量。样品用顶空-固相微萃取进行前处理。经优化的试验条件:1采用100μm聚二甲基硅氧烷萃取头;2离子浓度:样品匀浆液中含(w)30%氯化钠;3萃取温度为70℃±1℃;4萃取时间为30min。在气相色谱分离中用HP-5MS色谱柱,在质谱分析中采用全扫描和选择离子监测模式。15种农药的质量浓度均在0.05~1.0mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.02~0.10μg·kg-1之间。以2种果品作基体,在0.05,0.2,0.5mg·kg-1 3个浓度水平进行加标回收试验,测得回收率在71.0%~96.0%之间,测定值的相对标准偏差(n=5)在0.5%~9.8%之间。     

分散固相萃取-高效液相色谱-串联质谱法测定铁皮石斛中8种有机磷农药残留

建立了分散固相萃取结合高效液相色谱-串联质谱法(d-SPE-HPLC-MS/MS)测定铁皮石斛栽培过程中可能使用的8种有机磷农药。前处理采用Qu ECh ERS方法,样品先经水浸润,用乙腈高速均质提取,经分散固相萃取净化,Waters Atlantis T3色谱柱分离,电喷雾串联质谱多反应监测模式测定,基质匹配标准曲线外标法定量。8种有机磷农药在测定的范围内线性关系良好(R0.997),在10,50,100μg/kg添加水平下8种农药的回收率范围为75.9%~117.8%,相对标准偏差在2.1%~12.3%(n=6)之间;检出限和定量限分别为0.15~5.47μg/kg和0.84~8.52μg/kg。该方法样品前处理简单、快速、选择性好、灵敏度高,适合于铁皮石斛鲜样中多种有机磷农药的快速测定。     

固相萃取-衍生化-气相色谱-质谱法测定水中类固醇类雌激素

采用固相萃取-衍生化-气相色谱-质谱法同时测定水中4种类固醇类雌激素雌酮(E1)、17β-雌二醇(E2)、17α-乙炔基雌二醇(EE2)、雌三醇(E3)。样品经Oasis HLB固相萃取柱,以丙酮为溶剂进行洗脱后,采用吡啶、N-甲基-N-三甲基硅基三氟乙酰胺于40℃衍生化20min后,采用气相色谱-质谱仪分析。E1、E2、EE2和E3的线性范围分别为5.00~500μg·L-1和10.0~500μg·L-1,4种类固醇类雌激素的检出限(3S/N)在1.5~3.0μg·L-1之间,测定下限(10S/N)在5.0~10μg·L-1之间;方法用于实际水样的分析,加标回收率在86.8%~93.8%之间,测定值的相对标准偏差(n=7)在7.1%~11%之间。     

气相色谱法测定鲍鱼不同组织中的多氯联苯

提出了气相色谱法测定鲍鱼不同组织(肌肉、内脏、整贝)中的多氯联苯含量的方法。样品经正己烷超声萃取,硫酸净化后,肌肉样品只需再经过弗罗里硅土固相萃取小柱净化,内脏和整贝则还需经石墨化碳黑固相萃取小柱净化。用DB-5MS毛细管色谱柱分离,电子捕获检测器检测。7种多氯联苯的质量浓度在1.25~100μg·L-1范围内与相应的峰面积呈线性关系,检出限(3S/N)在0.04~0.06μg·kg-1之间。在0.25,2.50,20.0μg·kg-1 3个浓度水平进行加标回收试验,回收率在78.0%~102%之间,测定值的相对标准偏差(n=5)在3.4%~6.9%之间。     

气相色谱法测定食品中仲丁灵残留量

提出了气相色谱法测定食品中仲丁灵残留量的方法。样品用正己烷-丙酮(1+1)混合液提取,提取液经凝胶渗透色谱和固相萃取净化。用DB-1701色谱柱分离,电子捕获检测器测定。仲丁灵的质量浓度在10.0~500μg·L-1范围内与其峰面积呈线性关系,检出限(3S/N)为1.4μg·kg-1。添加10,20,50μg·kg-1 3个浓度水平进行加标回收试验,回收率在84.2%~97.2%之间,测定值的相对标准偏差(n=8)在3.8%~15%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.     

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.

     

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。     

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.     

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。