超声雾化顶空单滴微萃取-气相色谱-质谱法测定果汁中的芳香成分

本文建立了超声雾化顶空单滴微萃取-气相色谱-质谱(GC-MS)联用测定果汁中的β-月桂烯、D-柠檬烯和异戊酸叶醇酯含量的方法。考察了萃取溶剂、萃取时间、富集时间等影响芳香成分萃取效率的因素。在最优的实验条件下,对三种果汁中的芳香成分进行了分析,测得三种果汁中β-月桂烯、D-柠檬烯和异戊酸叶醇酯的含量分别为12.0~488.6μg·mL~(-1)、542.8~1.237×10~4μg·mL~(-1)和0.0470~498.5μg·mL~(-1)。方法的回收率范围为78.5%~110.4%,相对标准偏差为1.3%~4.4%。     

超高效液相色谱法同时测定洋常春藤中8种成分含量

建立了同时测定洋常春藤中绿原酸、隐绿原酸、芦丁、烟花苷、常春藤皂苷C、常春藤皂苷D、常春藤皂苷B和α-常春藤皂苷8种成分的超高效液相色谱法(UHPLC)。以80%甲醇为溶剂,将药材粉末于85℃、料液比1∶100条件下水浴回流1 h,制备供试品溶液;采用Agilent ZORBAX Eclipse Plus-C_(18)(2.1 mm×100 mm,1.8μm)色谱柱,以乙腈-0.05%磷酸溶液为流动相进行梯度洗脱。结果表明,上述8种成分均获得良好的分离度;仪器精密度、方法重复性的相对标准偏差(RSD)均小于3.0%;样品溶液在室温条件下24 h内稳定;8种成分在对应质量浓度范围内线性关系良好(r≥0.999 5),检出限为0.40～10.58μg·mL~(-1),定量下限为1.31～34.61μg·mL~(-1),平均回收率为97.3%～108%,RSD(n=6)为0.51%～3.2%。该方法适用于洋常春藤中上述8种化学成分的定量分析。     

RP-HPLC法同时测定复方公英片中3种活性成分的含量

本实验建立了RP-HPLC法同时测定复方公英片(板蓝根、蒲公英)中(R,S)-告依春、咖啡酸、阿魏酸3种成分的含量。采用Agilent ZORBAX SB-C_(18)(4.6mm×250mm,5μm)色谱柱,以甲醇(A)-0.1%磷酸水溶液(B)为流动相,梯度洗脱,流速1.0mL·min~(-1),柱温30℃,进样量5μL,检测波长为245nm((R,S)-告依春)、320nm(咖啡酸、阿魏酸)。结果(R,S)-告依春、咖啡酸、阿魏酸的质量浓度在0.595～5.950mg·mL~(-1)、0.291～2.91mg·mL~(-1)、0.009～0.082mg·mL~(-1)范围内与色谱峰面积呈良好的线性关系,精密度、稳定性和重复性良好,平均加样回收率分别为99.51%(RSD=1.75%)、99.50%(RSD=1.84%)、99.36%(RSD=1.69%)。该方法简便、快速、准确,可作为复方公英片的质量控制提供依据。     

注射液中酚磺乙胺及焦亚硫酸钠含量的同时测定

酚磺乙胺及焦亚硫酸钠均在酸性的吐温80-罗丹明6G体系中产生化学发光,但具体发光条件不同,因此利用化学发光分析法,在同一体系中根据不同条件可对针剂注射液中酚磺乙胺及焦亚硫酸钠的含量进行同时测定。酚磺乙胺的质量浓度在0.05~3.0μg·mL~(-1)范围内与光信号呈现良好的线性关系,检出限为0.01μg·mL~(-1),相对标准偏差小于3.5%(n=5)。测定焦亚硫酸钠的工作曲线线性范围为0.07~5.0μg·mL~(-1),检出限为0.02μg·mL~(-1),相对标准偏差小于4.2%(n=5)。该测定方法可用于针剂药物中酚磺乙胺及焦亚硫酸钠的含量测定,结果令人满意。     

三叉耳蕨挥发油HS-SPME-GC-MS分析

采用顶空固相微萃取和气质联用技术(HS-SPME-GC-MS),从根中鉴定了31个成分,从叶中鉴定了22个成分。其中有16个共有成分。三叉耳蕨根的挥发油的主要成分是十六醛(11.24%)、正十六酸(9.07%)、十六烷(6.31%)和2,6,10,14-四甲基-十五烷(6.05%)。叶的挥发油的主要成分是邻苯二甲酸二乙酯(9.85%)、(E)-4-(2,6,6-三甲基-2-环己-1-烯基)-3-丁烯-2-酮(9.32%)、6,10,14-三甲基-2-十五烷酮(8.25%)和(E)-4-(2,6,6-三甲基-1-环己-1-烯基)-3-丁烯-2-酮(8.05%)。     

乙醇敏化钛黄与蛋白质作用的共振光散射光谱研究及其分析应用

研究了在乙醇存在下钛黄（TY）与蛋白质作用的共振光散射（RLS）光谱特征 。基于RLS的增强,建立了一种测定蛋白质的新方法。考察了各种影响因素,在优 化条件下确定了RLS强度与蛋白质浓度之间的关系。当TY浓度为4 * 10~(-5)mol· L~(-1)时,牛血清白蛋白（BSA）、人血清白蛋白（HSA）和溶菌酶(lysozyme)的线 性响应范围分别为0.1～6.0 μg·mL~(-1), 0.1～5.0 μg·mL~(-1), 0.2～3.0 μg·mL~(-1),检出限分别为12.7 ng·mL~(-1), 11.6 ng·mL~(-1)和18.8 ng· mL~(-1)。三种合成样品五次平行测定的回收率和相对标准偏差（RSD）分别为96. 0%～102.3%和0.8%～3.2%。将该方法与经典的Bradford方法分别用于人血清试样中 蛋白的测定,两种方法的分析结果经F-检验和双总体T-检验证明无显著性差异。     

气相色谱-质谱法测定涂料中的六溴环十二烷

提出了用气相色谱-质谱法测定涂料中六溴环十二烷含量的方法。样品用二氯甲烷-丙酮(1+1)混合溶剂超声提取,提取液经硅胶固相萃取小柱净化、平行蒸发定量浓缩后,用DB-5MS毛细管柱进行分离,全扫描模式和选择离子监测模式测定。六溴环十二烷的质量浓度在1～50mg·L-1范围内与其峰面积呈线性关系,测定下限(10S/N)为10 mg·kg-1。添加5,20,50mg·L-1 3个浓度水平进行加标回收试验,回收率在82.0%～106%之间,测定值的相对标准偏差(n=8)在2.8%～5.3%之间。     

微波辅助萃取/高效液相色谱串联质谱法对山银花中活性成分含量的测定

建立了微波辅助萃取/高效液相色谱串联质谱法(MAE/HPLC-MS/MS)同时测定山银花中10种活性成分含量的方法。山银花药材采用MAE萃取,萃取溶剂为乙醇-水(7∶3),固液比1∶30,萃取温度70℃,萃取时间10 min。采用HPLC-MS/MS测定萃取液中活性成分的含量,色谱柱采用Agilent Poroshell120 SB-C18(100 mm×2.1 mm,2.7μm),以0.5%甲酸-乙腈为流动相进行梯度洗脱,负离子多重反应离子监测模式检测。在优化条件下,10种成分的定量分析在10 min内完成。结果表明,10种活性成分的线性范围为0.05～500 mg/L,相关系数(r)不低于0.996 9,检出限和定量下限分别在69～4 413μg/kg和231～14709μg/kg范围,回收率为94%～105%。采用该方法检测6个不同产地的山银花样品,10种活性成分的含量在3.98～14 356.31 mg/kg范围。该方法快速、准确,可有效地用于山银花药材的质量控制。     

氢核磁共振定量法测定盐酸伊托必利片含量

以马来酸作为内标物质,氢核磁共振定量法(qHNMR)测定盐酸伊托必利片中盐酸伊托必利的含量。选择盐酸伊托必利δ7. 31～7. 40处为定量峰,马来酸δ6. 31处为内标峰,在恒温300K,弛豫延迟时间15 s,采样时间4. 01 s,扫描次数为64次条件下采集盐酸伊托必利片的qHNMR图谱。比较HPLC法与qHNMR法测定盐酸伊托必利片含量的结果。qHNMR法在2. 31～18. 66 mg·mL~(-1)的范围内线性关系良好。低、中、高浓度的平均回收率分别为98. 52%、99. 72%、101. 11%,RSD为1. 17%(n=9),检测限(LOD)为50. 0 ng·mL~(-1),定量限(LOQ)为120. 0 ng·mL~(-1)。盐酸伊托必利片的qHNMR法含量测定结果与HPLC法的测定结果基本一致。qHNMR法可用于测定盐酸伊托必利片中盐酸伊托必利含量的测定。     

液相色谱-质谱法测定土壤和沉积物中的六溴十二烷

采用液相色谱-质谱法测定土壤和沉积物中六溴十二烷的含量。样品经索氏提取器或ASE快速溶剂萃取仪,用正己烷-二氯甲烷(1+1)混合溶剂提取,经硅胶净化柱净化。以Hypersil C18色谱柱为固定相,以水和甲醇-乙腈(8+2)溶液为流动相进行梯度洗脱,采用电喷雾负离子源-选择反应监测模式检测。α-六溴环十二烷、β-六溴环十二烷和γ-六溴环十二烷的质量浓度的线性范围为5.0~500μg·L-1,方法的检出限(3S/N)分别为12.5,12.4,9.95 ng·kg-1。应用该方法对土壤和沉积物中的六溴环十二烷进行测定,加标回收率在78.5%~111%之间,测定值的相对标准偏差(n=7)为4.1%~11%。     

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。     

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.     

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^-。     

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.     

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.     

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。     

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.