硝普钠分光光度法测定对乙酰氨基酚

建立了硝普钠分光光度法测定对乙酰氨基酚的方法。研究表明:在碱性条件下,对乙酰氨基酚与硝普钠以1∶2的化学计量比反应形成一种绿色产物,其最大吸收波长为698nm。对乙酰氨基酚在1.7～102μg·mL-1浓度范围内与吸光度成良好线性关系,线性回归方程为A=0.02804+0.02285c(μg·mL-1),线性相关系数r=0.9986,表观摩尔吸收系数ε698=3.5×103L·mol-1·cm-1,检测限(3s·k-1)为1.42μg·mL-1。本方法成功应用于药物样品中对乙酰氨基酚含量的测定,回收率在97.6%～102.0%,结果满意。     

硝普钠褪色分光光度法测定硼

在碱性条件下,硼酸与硝普钠能够形成二亚硝铣铁氢化硼,最大褪色波长为459 nm。硼的浓度在0.6~120.1μg·m L~(-1)范围内与吸光度降低的程度成良好线性关系,线性回归方程为A=-0.0165-0.0077C(μg·m L~(-1)),线性相关系数为0.9991,检测限为0.36μg·m L~(-1)。此外,还详细讨论了硼酸与硝普钠的反应机理。该方法用于药物样品中硼含量的测定,结果满意。     

硝普钠显色测定药物样品中甲巯咪唑

在溶液中NaOH浓度为6.7×10-3mol/L及0℃(冰水浴)条件下,反应时间为30 min,硝普钠与甲巯咪唑生成化学计量比为1碱性条件下硝普钠与甲巯咪唑反应生成化学计量比为1∶1的绿色产物,其最大吸收波长为610 nm。甲巯咪唑在4.8~48 mg/L浓度范围内与吸光度呈良好线性关系,线性回归方程为A=-0.0617 0.01329C(mg/L),相关系数r=0.9991;检出限为0.47 mg/L;相对标准偏差RSD=0.2%。本法成功用于测定片剂药品中甲巯咪唑的含量,平均回收率大于97.2%。     

固相配位化学反应研究 XXXX: 硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物的固相反应

本文用气相色谱、红外光谱和Mossbauer谱等手段, 研究了硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物在氢气氛中的固相反应, 发现过渡金属盐的存在或多或少地影响了硝普钠的分解方式, 其中CuCl~2.2H~2O与硝普钠室温时就反应生成Cu[Fe(CN)~5NO].χH~2O; 在较高温度下, CoCl~2.6H~2O和NiCl~2.6H~2O与硝普钠的固相反应催化了硝普钠迅速分解; 而氯化锰与硝普钠的固相反应与纯配合物较为接近。探讨了第一步反应可能的机理, 并计算了反应动力学参数。     

固相配位化学反应研究 XXXX: 硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物的固相反应

本文用气相色谱、红外光谱和Mossbauer谱等手段, 研究了硝普钠与锰(II)、钴(II)、镍(II)、铜(II)氯化物在氢气氛中的固相反应, 发现过渡金属盐的存在或多或少地影响了硝普钠的分解方式, 其中CuCl~2.2H~2O与硝普钠室温时就反应生成Cu[Fe(CN)~5NO].χH~2O; 在较高温度下, CoCl~2.6H~2O和NiCl~2.6H~2O与硝普钠的固相反应催化了硝普钠迅速分解; 而氯化锰与硝普钠的固相反应与纯配合物较为接近。探讨了第一步反应可能的机理, 并计算了反应动力学参数。     

固相配位化学反应研究 ⅩⅩⅩⅩ.硝普钠与锰(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)、铜(Ⅱ)氯化物的固相反应

本文用气相色谱、红外光谱和Mssbauer谱等手段,研究了硝普钠与锰(Ⅱ)、钴(Ⅱ)、镍(Ⅱ)、铜(Ⅱ)氯化物在氢气氛中的固相反应,发现过渡金属盐的存在或多或少地影响了硝普钠的分解方式,其中GuCl_2·2H_2O与硝普钠室温时就反应生成Gu[Fe(GN)_5NO]·xH_2O;在较高温度下,GoCl_2·6H_2O和NiGl_2·6H_2O与硝普钠的固相反应催化了硝普钠迅速分解;而氯化锰与硝普钠的固相反应与纯配合物较为接近。探讨了第一步反应可能的机理,并计算了反应动力学参数。     

硝普钠分光光度法测定头孢他啶

建立了硝普钠分光光度法测定头孢他啶的方法。实验结果表明,在碱性条件下,头孢他啶与硝普钠以1∶2的化学计量比反应形成一种红褐色产物,其最大吸收波长为528 nm。 头孢他啶在2.50~810 mg/L浓度范围内与吸光度呈良好线性关系,线性回归方程为A=0.02704+0.00218ρ(mg/L),线性相关系数r＝0.9987,表观摩尔吸收系数ε528=1.2×103 L/(mol·cm),检测限(3σ/k)为1.38 mg/L。 本方法操作简便、快速,成功用于药品中头孢他啶含量的测定。     

“乙醇的催化氧化”实验改进

利用硝普钠、纸巾等生活中常见物品,改进"乙醇的催化氧化"实验。1实验用品酒精灯、试管、烧杯、小量筒、纸巾、胶头滴管、直径约1mm铜丝、酒精、硝普钠、2 mol/L NaOH溶液等。2实验步骤及现象(1)取一支注射用硝普钠(规格:50 mg),加5mL水溶解,制得1%Na2Fe(CN)5NO溶液。该溶液对光敏感,其保存和应用不应超过24h。如果是做学生分组实验,可以通过淘宝网购买该溶液使用,价格更低,操作更简便。     

硝普钠分光光度法测定头孢噻肟钠

建立了测定头孢噻肟钠的新方法,碱性溶液中硝普钠与头孢噻肟钠生成了化学计量比为2∶1的产物,其最大吸收波长λmax=525 nm,表观摩尔吸光系数3.9×103L.mol-1.cm-1。头孢噻肟钠在0.91~200μg/mL浓度范围内与吸光度呈现良好线性关系,线性回归方程A=0.010+0.00816ρ(μg/mL),线性相关系数r=0.9994,检出限(3σ/k)为0.62μg/mL。方法可用于药物样品和血清中头孢噻肟钠含量的测定。     

硝普钠分光光度法测定头孢克肟

研究了硝普钠(SNP)与头孢克肟(CEF)之间的显色反应机理,确定了最佳反应条件,建立了一种测定CEF的新方法。结果表明:在NaOH溶液浓度为0.17mol/L的碱性介质中,控制温度40℃,反应30min,CEF与SNP以1∶2化学计量比生成一种含亚硝基的红褐色化合物,最大吸收波长为530nm,表观摩尔吸光系数ε=1.96×103L/(mol·cm)。CEF的浓度在0.8~400μg/mL范围内服从比耳定律,线性相关系数为0.9991,检测限(3σ/k)为0.48μg/mL。     

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。     

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。     

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。