微波消解-分光光度法快速测定农药废水中的总磷

利用微波消解技术对农药废水样品进行预处理,然后进行其中总磷的测定,消解时间从传统的高温高压消解30 min缩短到8 min.用微波消解-分光光度法和高压消解-分光光度法对两个农药废水样品进行了6次平行比对测定,测定结果经统计检验无显著性差异.微波消解法测定结果的相对标准偏差为0.483％～0.906％(n=6),加标回收率为95.5％～97.0％.该方法准确、快捷,适用于农药废水中总磷的快速测定.     

密封恒温分光光度法快速测定化学需氧量

建立了密封恒温消解样品,测定化学需氧量（CDDcr)的分光光度法。应用正交试验法确定了密封恒温法消解试样的最佳条件,此方法有机物的氧化率为98.33%-99.50%。CODcr值在0-800mg/mL范围内符合比耳定律。样品测定的相对标准偏差为0.39%（n=12),加标回收率为97.50%-99.56%。用该法测得的CODcr值与标准回流法所得结果一致。     

密封消解法测定COD的研究

探讨了用XJ-Ⅰ型COD消解装置快速处理水样,KMnO4滴定测定化学需氧量的新方法.对常规消解和密封消解的两种测试方法进行了比较,实验结果表明,密封法消解应用于环境污水的分析,具有试剂用量少,加热速度快,准确度高等优点.     

微波消解凯氏定氮法快速测定酱油中全氮

研究了凯氏定氮法测定酱油中全氮时样品的微波消解方法,进行了微波消解条件的选择及消解结果精密度试验,并与国家标准方法对比,验证了方法的准确度。试验结果表明,消解完全仪需20min,相对标准偏差均小于2%（n=7）,回收率范围为96%～103%,经t检验,微波溶样法与国家标准凯氏定氮法的测定结果无显著性差异。     

提高化学需氧量比色法测定准确度的研究

HACH密封消解比色法测定化学需氧量(COD) 即在传统的COD测定方法[1]基础上,采用密闭条件消解试样, 比色法测定, 具有批量分析、快捷简便等优点,统计检验表明,COD快速测定法与标准回流法比较,其分析结果无显著性差异,在准确度、精密度方面与标准回流法具有可比性.     

冷原子荧光光谱法测定沉积物中总汞方法的改进

应用国家标准方法(GB/T 22105.1-2008)测定沉积物中总汞量时,对其中的样品消解方法作如下改进:①试样置于盐酸-硝酸(3+1)混合酸中浸泡过夜,次日加水定容为50mL,取其上层清液供冷原子荧光光谱法测定其总汞量;②上述试样溶液如在1～3d内分析毋需加入保护剂及稀释剂,按改进后的方法,总汞的质量浓度在4.00ng.L-1以内与荧光强度呈线性关系,检出限(3S/N)为0.011ng.L-1。用于沉积物中总汞的测定,经t-检验与国家标准方法测定值无显著差异。方法的日内(n=6)和日间(n=5)相对标准偏差分别在1.1%～3.7%和5.9%～7.0%之间。     

程序控温湿法消解石墨炉原子吸收法测定苹果中的铅

对程序控制温度、湿法消解苹果样品中铅的消解条件和石墨炉原子吸收光谱测定方法进行了研究和探讨。在本法选择的条件下,回收率为92．0％～107．0％,相对标准偏差为4．1％。经t检验及对比实验证明,与国家标准方法无显著差异。     

水中总磷量的密闭微波增压消解快速测定

研究了用聚四氟乙烯密封带密封容器，利用微波加热技术，在较高的温度和压力下消解样品，快速测定环境水样中总磷量的方法；讨论了微波功率、微波消解时间、酸度等因素对测定结果的影响，与标准方法对照，经t检验法及F检验法检验，测定结果没有显著性差异，多次加标回收率在98％－103％之间，相对标准偏差≤1．3％，结果令人满意；该法具有操作简便、快速、不污染环境、宜于大批量样品的测定、便于推广普及等优点，可用于其它样品的分析测定。     

微波消解样品-电感耦合等离子体原子发射光谱法测定刺参体壁中微量元素

刺参体壁中5种微量元素（锌、铁、铜、铬及锰）,采用电感耦合等离子体原子发射光谱法（ICP-AES）进行测定。试样置于聚四氟乙烯消解罐中,加入10mol·L^-2次氯酸溶液5mL后加盖密闭,在MDS-2003F型密闭压力自控微波消解仪中进行消解,所得溶液供ICP-AES测定。统计检验的结果表明：所测得的结果与常规方法所得结果之间无显著差异。对方法的精密度与回收率作了试验,所测得的相对标准偏差（n=5）在1．09％～3．16％之间,回收率在93．49／6～102．6％之间。     

流动注射光度法测定水中总磷方法的改进

对全自动流动注射分析仪的分析流路进行了改进,将先消解后进样的模式改为先进样后消解的模式,提出了一种改进的流动注射光度法测定水中总磷含量的方法。总磷的质量浓度在0.01～2.0mg.L-1范围内与吸光度呈线性关系,检出限(3S/N)为1.4μg.L-1。方法用于水样中总磷的测定,经t-检验测定值与国标法测定值无显著差异。水样的加标回收率在93.0%～105.0%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。     

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。     

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.     

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.     

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。     

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.     

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。