电感耦合等离子体质谱法测定烟酰胺药物元素杂质

建立了烟酰胺药物中30种元素杂质的ICP-MS分析方法,并根据USP< 233>进行了验证,在优化的实验条件下,本方法的检出限在4.0×10-4～0.4μg/L之间,加标回收率在86.3％～116.0％之间,与ICP-OES检测结果基本一致.用所建立方法对烟酰胺以及稳定性样品进行了元素杂质检测,根据样品制备工艺初步判断元素杂质的来源.     

电感耦合等离子体发射光谱(ICP-AES)法测定铂金材料中杂质元素

建立了微波消解-电感耦合等离子体原子发射光谱(ICP-AES)法同时测定铂饰品国家标准物质中金、铜、铱、钴、钯、铑、钌7种杂质元素含量的方法.方法中7种元素的检出限为:钯与钌＜0.0001％,其它元素＜0.00062％.经与国家标准物质认定值比对,结果满意.稀释系数95.5％～104.7％.方法测定结果与标准样品认定值一致,可满足铂金材料中杂质元素检测.     

等离子体质谱多内标法测定金属铒中多种痕量元素

本方法采用ICP—MS法同时测定高纯金属铒中14个稀土元素和15种非稀土元素杂质，确定了合适的样品稀释浓度，采用Sc、In、Cs、Tl4个内标，杂质元素的检出限在0．04～16μg／g之间，样品的加标回收率在86％～105％之间，能够满足4N金属铒产品的检测需求。     

Microwave Digestion-ICP- OES Determination of Common or Micro Impurities in Titanium Slag

钛渣样品采取高压密闭微波加热方式以HF、HNO3进行消解,采用电感耦合等离子体原子发射光谱法(ICP- OES)直接同时测定常量、微量杂质铁、铅、砷、铬、铜、磷、锰、钒、镁、钙.考察了消解条件、基体钛以及共存元素之间的干扰影响、等离子体参数等测定条件,通过优选元素分析谱线、以及采用基体匹配与同步背景校正相结合的方式消除光谱干扰和基体效应.测定50、60、70、80、90等不同品位钛渣中杂质元素的结果表明:方法检测范围涵盖了0.005％～10.0％的钙、镁、铁,以及0.005％ ～2.0％的铅、砷、铬、铜、磷、锰、钒,校准曲线相关系数大于0.9992;背景等效浓度0.002％ ～0.0015％,检测限0.0009～0.0038％;含量不小于1.0％的RSD低于0.677％,在0.010％～0.10％含量范围内RSD低于3.85％;回收率为90.0％～108.0％.以本法对70、80、90 3个高钛渣标准样品的定值分析结果与传统化学方法对照一致.     

表面增强拉曼光谱法同时检测奶粉中三聚氰胺和二聚氰胺

本文建立了奶粉中同时检测三聚氰胺及二聚氰胺的表面增强拉曼光谱法.奶粉样品经15％三氯乙酸溶液提取,中性氧化铝吸附杂质后进行拉曼光谱检测.三聚氰胺线性范围为0.0050～0.075 mg/L,检出限为0.0015 mg/L,回收率在79.5％～124％之间,相对标准偏差小于8.8％(n=5);二聚氰胺线性范围为0.50～l0mg/L,检出限为0.15 mg/L,回收率在76.5％～112％之间,相对标准偏差小于9.4％(n=5).该方法相比常规表面增强拉曼光谱法,仅通过一种样品前处理手段即可对奶粉中的三聚氰胺或二聚氰胺进行定性检出及定量分析,相比色谱等检测方法具有样品前处理过程简单、耗时短等优点,在奶粉质量监控方面具有良好的应用前景.     

离子交换色谱-电感耦合等离子体质谱法测定高纯钛中痕量杂质元素

建立了离子交换色谱-电感耦合等离子体质谱(ICP-MS)测定高纯钛中Mg、Cr、Fe、V、Mn、Co、Ni、Cu、Zn、Sr、Cd、Ba、Tl、Pb等痕量杂质元素分析方法,并对ICP-MS工作参数及条件进行了优化和选择.高纯钛用HF和HNO3溶解后进入离子色谱的阳离子交换柱,经HF(3+97)淋洗后,用HNO3洗脱,洗脱下来的溶液进入电感耦合等离子体质谱检测.方法的检出限在0.00099～0.85 μg/L之间,测定下限为0.0033～2.8 μg/L,各元素的回收率在90%～110%之间.利用本方法对纯度＞99.99%高纯钛样品的杂质元素进行分析,结果表明,其精密度和准确度均满足痕量分析的要求.     

电感耦合等离子体质谱法检测氧化镓中杂质元素

建立了电感耦合等离子体质谱法(ICP-MS)测定氧化镓中杂质元素的检测方法,采用微波消解技术溶样,以5 ng/mL Rh为内标补偿校正镓基体的抑制效应,采用碰撞室技术(CCT)消除多元素分子离子的干扰.方法的检出限为0.10～1.0 ng/mL,加标回收率在85%～110%之间,RSD为0.6%～7.1%.该方法能满足99.95%～99.995%氧化镓中杂质元素的分析要求.     

ICP-AES法测定出口工业硅中11种杂质元素

利用ICP-AES分析技术,对试样溶解方法,元素分析谱线,共存元素干扰,仪器分析参数,无机酸介质影响等因素进行了研究,确定了最佳工作条件,建立了可同时测定出口金属硅中11种杂质元素的简单、快速和适用的分析方法,结果表明,该方法线性范围宽,检出限低,准确性高,操作步骤简单,11个元素测定回收率在85％～105％之间,相对标准偏差在1．9％～8．1％之间。     

二阶导数-同步荧光法同时测定微量维生素B_1,B_2和烟酰胺

建立了二阶导数-同步荧光法同时测定微量维生素B1,B2和烟酰胺含量的方法.在最佳实验条件下,维生素B1,B2和烟酰胺的检测限分别为2.1,2.6,和2.8 ng/mL,相对标准偏差为1.5%～4.9%,加标回收率为92%～105%.该方法可用于样品中微量维生素的测定.     

电感耦合等离子体质谱法测定太阳能级多晶硅中杂质元素

多晶硅样品经氢氟酸和硝酸混合酸消解,采用电感耦合等离子体质谱法测定所得样品溶液中23种杂质元素的含量。通过调整分辨率来调整多原子离子对部分被测元素的干扰。方法的检出限(3s)在0.3～19.7ng.g-1之间。方法用于太阳能级多晶硅样品中23种元素的测定,回收率在85.2%～111%之间,相对标准偏差(n=11)在0.9%～4.6%之间。     

利用手持技术改进测定乙醇分子结构实验

利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

光谱仪测试范围的扩展

由于石化行业的生产需要，其材质的使用具有多样性和广泛性，经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识，根据光谱仪的测试能力及标样的采集，实现了一个或几个元素测量范围的扩展，并对其测量的影响因素进行了研究。     

Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin

The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.     

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.     

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.

     

物质分配系数的测定实验改进

实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。     

Calculation of enthalpies of hydrogenation of hydrocarbons

Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.     

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。