高效液相色谱-荧光-紫外串联测定土壤中16种多环芳烃

采用高效液相色谱-荧光-紫外检测器串联测定土壤中16种多环芳烃。通过液相色谱柱、荧光激发和发射波长等条件的优化,实现16种多环芳烃组分基线完全分离来和15种多环芳烃荧光高灵敏度检测,并通过荧光-紫外串联检测来提高定性的准确度等。在优化的实验条件下,荧光检测器的检出限为0.015~0.8μg/L;紫外检测器检出限为0.4~30μg/L;方法精密度为0.58%~1.36%(荧光)、1.13%~5.48%(紫外);样品加标回收率为76.4%~111%。     

ACF-SPME检测海洋水体中的多环芳烃

使用新型活性炭纤维(ACF)作为固相微萃取(SPME)技术的萃取纤维,检测了海水中的多环芳烃。得到ACF-SPME萃取多环芳烃的最优条件为:在搅拌条件下,盐浓度10%,pH3,温度60℃水浴中直接萃取40min。并确定16种多环芳烃的RSD(n=5)为1.8%～10%、线性范围为0.1～500μg/L、检出限为0.1～100μg/L。对东海近海海水进行了分析,结果表明海水中PAHs浓度在检测限以下,同时进行加标回收实验,得到16种多环芳烃的回收率在80%～128%。     

沥青基活性炭纤维复合活化工艺的研究

以沥青基炭纤维为原料，研究了用铵盐作为化学活化剂对其进行浸渍预处理，然后采用（H2O＋CO2）活化的方法制备活性炭纤维，讨论了工艺条件对活性炭纤维性能的影响并通过光电子能谱XPS探讨了活化过程中炭纤维表面官能团的变化。结果表明：采用这种物理和化学复合活化工艺，可以在较高得率下提高活性炭纤维比表面积。同时浸渍处理、H2O流量、活化温度和活化时间等工艺参数显著影响活性炭纤维的比表面积和得率，优化的工艺为：经铵盐浸渍6h，炭纤维在水蒸气与CO2流量比3：1的混合气氛中900℃活化30min。XPS研究表明，活化后炭纤维表面的含氧官能团C－O明显减少，铵盐浸渍未能增加活性炭纤维表面的含氮基团。     

漩涡辅助液液微萃取-气相色谱法测定水样中痕量多环芳烃

建立了漩涡辅助分散液液微萃取(VAEDLLME)结合气相色谱测定环境水样中12种多环芳烃的方法。对萃取剂种类和体积、漩涡时间以及盐浓度的影响等参数进行优化。实验结果表明,方法线性范围为0.1~5.0μg/L,相关系数r≥0.9851,检出限为0.001~0.01μg/L,加标回收率为95.0%~124.4%,相对标准偏差(RSD)为1.4%~27%。方法适用于环境水样中12种多环芳烃的分析检测。     

超声波提取–气相色谱–质谱联用法测定城市污水处理厂脱水污泥中16种多环芳烃

采用超声波提取,气相色谱–质谱联用法检测,建立城市污水处理厂脱水污泥中16种多环芳烃的测定方法。以二氯甲烷–正己烷(体积比为1∶1)为提取剂,超声波提取20 min。在优化的仪器条件下,16种多环芳烃的质量浓度在0.05~100μg/m L范围内与色谱峰面积呈良好线性关系(r≥0.999 3),方法的检出限在0.12~0.38μg/kg之间,加标回收率为80%~120%,测定结果的相对标准偏差小于4.5%(n=6)。该方法样品前处理简单、重现性好、检出限低、准确度高,适用于城市污水处理厂脱水污泥中16种多环芳烃的测定。     

非平衡体系中固相微萃取技术的定量分析研究--快速监测水中痕量的有机污染物(多环芳烃)

采用固相微萃取技术,以100μm膜厚的聚二甲基硅氧烷纤维萃取水中10种多环芳烃,在60min采样时间内纤维上的吸附量与采样的时间近乎成正比,分配体系达到平衡前可以定量地测定水中的待测物.该方法的线性范围在0.1～100μg/L,检出限在0.01～0.03μg/L,15μg/L的回收率在80%～100%,相对标准偏差在20%以下.     

磁性微孔聚合物富集/表面增强拉曼光谱法测定水与土壤中多环芳烃

建立了磁性聚亚苯基共轭微孔聚合物富集/表面增强拉曼光谱法测定水样和土壤中4种多环芳烃的分析方法。待测物经磁性聚亚苯基共轭微孔聚合物吸附萃取,甲醇洗脱后进行SERS检测。结果表明,蒽、芘、荧蒽和苯[α]芘在0.1~10μg/L范围内与其SERS特征峰峰强呈良好的线性关系,检出限为0.03μg/L,回收率为71.6%~115.8%,相对标准偏差不大于13.7%。该分析方法灵敏度高,能够满足实际水样和土壤中4种多环芳烃同时检测的要求。     

分散固相萃取净化/高效液相色谱法测定婴幼儿奶粉与米粉中15种多环芳烃

建立了高效液相色谱-荧光检测法同时测定婴幼儿奶粉和米粉中15种多环芳烃的检测方法。样品经乙腈提取,PSA分散固相萃取净化;乙腈-水梯度洗脱,Waters PAH专用柱分离,荧光检测器检测,外标法定量。在最优条件下,15种多环芳烃均得到有效分离,线性范围为1.0~50μg/L,相关系数均大于0.995,方法检出限(LODs,S/N=3)为0.05~0.3μg/kg,回收率为86.5%~106.8%,精密度(RSD,n=6)为0.7%~7.5%。该方法操作简单、灵敏度高,适用于婴幼儿奶粉和米粉中多环芳烃的检测。     

凝胶色谱净化-气相色谱-质谱法同时测定烧烤肉制品中19种多环芳烃

提出了凝胶色谱净化-气相色谱-质谱法同时测定烧烤肉中19种多环芳烃含量的方法。烧烤肉样品经正己烷-二氯甲烷(1+1)溶液超声提取30min后,上清液经凝胶色谱净化,所得净化液用HP-5MS色谱柱分离,全扫描模式和选择离子监测模式测定。19种多环芳烃的峰面积与质量浓度在5~200μg·L-1范围内呈线性关系,检出限(3S/N)在0.1~0.5μg·kg-1之间。在20,40,80μg·kg-1 3个浓度水平进行加标回收试验,19种多环芳烃的回收率在58.0%~122%之间,相对标准偏差(n=6)小于21.5%。     

纳米多孔双金属氧化物在镍钛合金纤维上的原位生长及其对多环芳烃的选择性固相微萃取

采用阳极氧化法在镍钛合金(NiTi)纤维上原位生长了双金属氧化物纳米孔(NiTiONPs)涂层,通过扫描电镜(SEM)和能谱(EDS)考察了电解质组成和电压对形貌的影响。将NiTiONPs涂层的NiTi纤维与高效液相色谱-紫外检测器联用,研究了4种典型芳香分析物的萃取性能。结果表明,富含TiO2的NiTiONPs涂层对多环芳烃(PAHs)具有良好的萃取效率,尤其对苯并[a]芘的萃取选择性优于市售聚二甲基硅氧烷纤维和聚丙烯酸酯纤维。在优化条件下,PAHs的线性范围为0.05~200μg/L,相关系数均大于0.999,检出限为0.012~0.134μg/L。对单支纤维日内和日间分析的相对标准偏差(RSDs)分别为4.0%~5.5%和6.0%~6.8%,使用分批组装的5支纤维分析的RSDs为6.4%~7.6%。实际水样分析的加标回收率为84.5%~111.5%。所制备NiTi纤维至少可重复使用250次以上,重现性好。     

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.     

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.     

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^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

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.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。