阻抑褪色光度法测定微量硫代硫酸根

基于加热和pH =5 .0～ 6.0条件下 ,硫代硫酸根抑制H2 O2 氧化结晶紫 (CV)的褪色反应 ,建立了一种测定硫代硫酸根的方法。硫代硫酸根在 4.5× 1 0 -5～ 4.5× 1 0 -4g/L范围内服从比耳定律 ;检出限为 3 .2×1 0 -6g/L。本法用于定影废液中硫代硫酸钠含量的测定 ,结果满意。     

基于甲醇自由基还原波的甲醇极谱测定

利用过硫酸根在电极上还原产生的硫酸根自由基SO4· - 将甲醇氧化成甲醇自由基HC·HOH ,该自由基还原产生极谱还原波 ,拟定了极谱测定甲醇的新方法。在 0 .0 33mol/LKH2 PO4+Na2 HPO4(pH 6.1± 0 .1 ) + 1 .6× 1 0 - 2 mol/LK2 S2 O8介质中 ,甲醇自由基还原波峰电流与甲醇浓度在 3.1 5× 1 0 - 4 mol/L～ 9 46× 1 0 - 3mol/L范围呈线性关系。用该方法测定了甲醇生产车间空气中的甲醇含量     

测定利血平的流动注射化学发光新体系

研究了利血平在酸性条件下与高碘酸钾和过氧化氢产生化学发光的行为 ,建立了高碘酸钾 -利血平 - H2 O2 - H2 SO4 流动注射化学发光新体系。利血平的浓度在 1 .0× 1 0 - 6～ 1 .0× 1 0 - 4g/m L范围内与化学发光强度呈良好的线性关系 ,检出限为 2 .7× 1 0 - 7g/m L。对 2× 1 0 - 5g/m L利血平进行 1 1次平行测定 ,得该法的相对标准偏差为 2 .63%。方法用于利血平片剂含量的测定 ,结果与药典法测得值一致     

流动注射-化学发光法测定盐酸林可霉素

盐酸林可霉素在 Na IO4 - H2 O2 - H+体系中能发生强的化学发光反应 ,据此建立了一种测定盐酸林可霉素的流动注射 _化学发光分析法 ,方法的检出限为 3.6× 1 0 -8g/m L,相对标准偏差为 1 .0 % (c S=1 .0× 1 0 -6g/m L,n=1 1 ) ,线性范围为 1 .0× 1 0 -7～ 9.0× 1 0 -5g/m L。该方法已用于盐酸林可霉素注射液的分析     

高锰酸钾-甲醛-尿酸化学发光体系的研究

在甲醛存在下,高锰酸钾与尿酸能够发生化学发光反应,产生很强的化学发光。据此采用流动注射技术,建立了一种利用高锰酸钾甲醛尿酸化学发光体系测定尿酸的化学发光分析法。方法的检出限为6×10-6 g/L;相对标准偏差为1. 8% (4. 0×10-4 g/L尿酸,n=11 );线性范围为2. 0×10-5 ~5. 0×10-3g/L。本法用于人体尿液中尿酸的测定,结果令人满意。并探讨了反应机理。     

四种阴离子的毛细管电泳电导检测(英文)

 采用柠檬酸 柠檬酸钠作为缓冲体系 ,使用负高压 ,对Cl-,NO3 -,HCO3 -和H2 PO4 -等 4种常见阴离子进行了分离检测 ,研究了缓冲剂的种类、浓度、pH值及操作电压对分离的影响。在选定的条件下 ,4种离子的定量线性范围 :Cl-5 0× 10 -5mol/L～ 2 5× 10 -3 mol/L ,NO3 -6 0× 10 -5mol/L～ 2 0× 10 -3 mol/L ,HCO3 -5 0× 10 -6mol/L～ 2 0× 10 -4 mol/L ,H2 PO4 -6 0× 10 -5mol/L～ 1 0× 10 -3 mol/L ;检出限 :Cl-1 5× 10 -5mol/L ,NO3 -3 0×10 -5mol/L ,HCO3 -1 0× 10 -6mol/L ,H2 PO4 -2 0× 10 -5mol/L ;峰面积的RSD (n =6 ) :Cl-3 1% ,     

蝶呤类化合物的荧光性能研究

研究了蝶呤类化合物的天然荧光特性。着重考察了新蝶呤、生物蝶呤、黄蝶呤和蝶呤在 p H7.7磷酸盐缓冲溶液条件下的荧光光谱及各种因素对其荧光强度的影响。在最佳实验条件下 ,四种蝶呤类化合物的线性范围为 :蝶呤 0 .6～ 2 .8μg/m L,新蝶呤 0～ 2 .6μg/m L,生物蝶呤 0～ 2 .4μg/m L,黄蝶呤 0～ 6.0 μg/m L,检出限依次为 :4.2 9× 1 0 - 7g/m L,6.71× 1 0 - 8g/m L,5.79× 1 0 - 9g/m L和 1 .75× 1 0 - 8g/m L     

锌电解液中痕量铜、镉、镍和钴的快速同时测定

研究了丁二酮肟 氨 氯化铵 柠檬酸钠 明胶 抗坏血酸体系中Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )的络合物吸附波 ,建立了同时、快速测定锌电解溶液中这些痕量元素的新方法。Cu(Ⅱ )、Cd(Ⅱ )、Ni(Ⅱ )和Co(Ⅱ )分别在 - 0 44V、- 0 76V、- 1 0 7V和 - 1 2 4V左右产生灵敏的络合物吸附波。信噪比为 3时 ,其检测限分别为 1 0× 1 0 - 8mol/L、1 3× 1 0 - 8mol/L、2 9× 1 0 - 1 0 mol/L和 3 6×1 0 - 1 1 mol/L。铜、镉、镍和钴的浓度分别为 2 0× 1 0 - 8mol/L～ 2 0× 1 0 - 5 mol/L、3 0× 1 0 - 8mol/L～ 3 0× 1 0 - 5mol/L、5 4× 1 0 - 1 0 mol/L～ 5 4× 1 0 - 7mol/L和 6 8× 1 0 - 1 1 mol/L～ 6 8× 1 0 - 8mol/L时 ,与相应峰电流之间有良好的线性关系。方法已用于锌电解液中铜、镉、镍和钴的快速同时测定 ,相对标准偏差分别小于或等于 4 7%、5 1 %、4 9%和 5 3 %。     

流动注射化学发光法测定扑热息痛

研究发现在碱性条件下 ,扑热息痛对鲁米诺 -铁氰化钾体系发光反应具有强烈的抑制作用 ,据此建立了流动注射化学发光测定痕量扑热息痛的新方法。扑热息痛浓度在 4 .0× 1 0 - 5～1 .0× 1 0 - 3g L范围内与发光强度呈良好的线性关系 ;检出限 ( 3σ)为 2 .4× 1 0 - 6 g L。相对标准偏差 (C =8.0× 1 0 - 4 g L ,n =1 1 )为 2 .3 %。方法用于片剂中扑热息痛含量测定 ,结果与标准方法一致。讨论了此体系发光机理     

火焰原子吸收光谱法间接测定青霉素V钾

基于青霉素V钾在酸性条件下的水解产物可与Pb2 + 形成沉淀 ,用火焰原子吸收光谱法测定沉淀中铅的含量 ,可间接测定药片中青霉素V钾的含量。在优化条件下 ,测定青霉素V钾的线性范围为 5 .15× 10 -5～ 4 .12× 10 -4mol/L ,线性回归方程为A =2 .4 2× 10 3 c - 0 .0 6 3 1,相关系数为 0 .999 1,检出限为 7.392× 10 -7mol/L ,测定结果的相对标准偏差为 0 .0 6 %～ 0 .6 9% ,回收率为 97.8%～ 10 2 .0 %。     

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.     

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。