以盐酸肼还原天青I催化光度法测定痕量钼

基于天青Ⅰ与盐酸肼氧化还原反应钼的催化活性,拟定了测定痕量钼新的动力学方法。本法钼的检测限为6×10~(-4)μg/ml,可测定浓度范围为1×10~(-3)～9×10~(-1)μg Mo/ml。本法可用于井水、温泉水和废水中钼的测定。     

无机偶合反应化学发光分析 Ⅱ.H_2O_2-Na_2S_2O_3-鲁米诺体系测定痕量钼

本文将钼催化过氧化氢氧化硫代硫酸钠的反应与鲁米诺-H_2O_2化学发光反应相偶合,建立了痕量钼的无机偶合反应化学发光分析法。此方法的检出限是1.2×10~(-10)g/ml钼,相对标准偏差为2.7％(对5×10~(-9)g/ml钼11次测定),工作曲线的线性范围为1×10~(-9)～1×10~(-3)g/ml。此法巴成功地用于天然水中痕量钼的测定。     

磷钼蓝光度法测定钼

利用磷钼杂多酸测磷,这是众所周知的,但用于钼的测定,还未见报道。本文提出在含MoO_4~(2-)溶液中,过量PO_4~(3-)的存在下使之形成磷钼杂多酸,经抗坏血酸还原后,直接用于钼的测定,方法十分简便。在测定波长690nm处,摩尔吸光系数为7.0×10~2,钼量在0—12mg/mL范围内符合比尔定律,满足高含量钼快速分析的要求。方法用于钼铁中钼的测定,获得较为满意的结果。     

钼簇合物的簇解反应和两个多钼酸盐化合物的晶体结构

含μ-Cl桥的三核钼簇阴离子[Mo~3(μ~3-O)(μ-Cl)~3(μ-OAc)~3Cl~3]^-在Fe^3^+作用下发生簇解反应, 形成钼同多酸盐[FeCl(DMF)~5][Mo~6O~1~9]。在合成[Mo~3(μ~3-S)(μ-S~2)~3(dtp)~3Cl]簇合物的反应中如果有CuI存在, 则形成钼磷杂多酸盐(Et~4N)~4[PMo~1~2O~4~0](DMF)~2。本文报道这两个多钼酸盐化合物的晶体结构, 并讨论有关的簇解反应。     

用CL—7301萃淋树脂分离铼和钼

本工作研究了CL—7301萃淋树脂从含铼钼的H_2SO_4-(NH_4)_2SO_4水溶液中分离铼钼的性能。铼和钼的吸附率都随溶液酸度增加而降低,但铼的吸附率远比钼的大。两者的分离系数在1～6N酸度范围内4N时有最大值,β_(Mo)~(Re)=120。铼的饱和吸附容量随铼浓度的增加而增大。柱吸附实验表明,铼的吸附容量达28毫克·克~(-1)树脂。用氨水淋洗铼几乎全部被洗脱,回收率接近100％,而钼的吸附量低于0.17毫克·克~(-1)树脂。溶液的铼含量可由0.3克·升~(-1)浓集到10克·升~(-1)以上,钼含量由5.0克·升~(-1)降至0.05克·升~(-1)以下,使二者达到有效的分离。     

分光光度法同时测定鬼针草中锗和钼的含量

采用苯基荧光酮(苯芴酮)-CTMAB分光光度法对鬼针草中锗和钼的含量同时进行了测定。实验表明,锗质量浓度在0~1.1μg/mL、钼质量浓度在0~1.1μg/mL与吸光度呈线性关系。相关系数(r):锗为0.994,钼为0.971。摩尔吸光系数:锗ε514.50=8.29×104L.mol-1.cm-1,钼ε524.50=5.56×104L.mol-1.cm-1。方法检出限:锗为6.08μg/L;钼为12.62μg/L。回收率:锗为100.0%,钼为99.2%。RSD:锗为0.2%,钼为0.2%。     

催化光度法测定痕量钼：钼（Ⅵ）—盐酸联氨—酸性品红体系

基于钼(Ⅵ)催化盐酸联氨还原酸性品红反应,拟定了测定痕量钼的新催化光度法。可测定钼量范围为0.04～9.0μg/ml,检出限为4.6×10~(-3)μg/ml。用于测定豆类中钼。     

Mo-苯芴酮-Triton X-100增溶光度法测定微量钼

应用有机染料测定微量钼的光度法,灵敏度虽高但操作较繁琐。随着保护胶和表面活性剂的应用,微量钼的测定又有一些灵敏度较高的方法。用阿拉伯树胶作为钼与苯芴酮络合物的保护胶比色测定钼,摩尔吸光系数为3.02×10~4。用氯化十六烷基吡啶作为钼与苯芴酮络合物的增溶剂,可在波长540nm处测定钼。用溴化十六烷基三甲基铵作钼与苯芴酮络合物的增溶剂,摩尔吸光系数为1.03×10~5。我们用非离子表面活性剂Trition X-100作钼     

电感耦合等离子体发射光谱法测定铀钼合金中钼EI北大核心CSCD

采用电感耦合等离子体发射光谱(ICP-AES)法测定铀钼合金中钼含量,考察了合金溶解、溶液中钼水解以及铀钼萃取分离等条件。确定溶液中H+浓度在3 mol/L时,铀钼合金在24 h内不会发生水解。选择发射波长202.031 nm为分析谱线。铀钼合金中钼含量在10~160μg/mL范围内呈线性关系,线性方程为y=3614.4x-1978,相关系数为0.9998,方法相对标准偏差小于1%。     

还原剂与鲁米诺化学发光反应的研究：Ⅲ.钼（Ⅲ）—鲁米诺化学发光反应

本文发现钼(Ⅱ)与鲁米诺可以发生化学发光反应,产生很强的发光信号,不稳定的钼(Ⅱ)可在流动注射体系中通过锌汞齐还原柱由钼(Ⅵ)产生。此反应能够用于痕量钼的测定。方法的线性范围是1×10~(-9)～4×10~(-7)g/ml钼,相对标准偏差小于2％(n=11)。此方法用于测定几种水样和钢样中的痕量钼,得到满意的结果。     

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。