高碘酸钾-酸性品红-NTA-DDMAA体系催化光度法测定良量锰

报道了以氨三乙酸为活化剂,以N-十二烷基二甲基铵基乙酸(DDMAA)为增敏剂,高碘酸钾氧化酸性品红催化光度法测定痕量锰的新方法,在DDMAA存在下,灵敏度提高了7倍(Mn²⁺量为1.2～2.4μg/L)和14倍(Mn²⁺量为2.4～5.2μg/L),相对标准偏差为2.0%,检出限为1.4×10^-7g/L,可用于茶叶中锰的测定.     

以N-十二烷基二甲基铵基乙酸为增敏剂催化光度法测定锰

基于存在增敏剂N-十二烷基二甲基铵基乙酸（DDMAA）和活化剂氨三乙酸,锰（Ⅱ）催化高碘酸钾氧化萘酚绿B的反应,拟定了测定痕量锰的新催化光度法。本法在两性表面活性剂DDMAA存在下,灵敏度提高10．3倍（Mn~(2+)量为0~6．0μg/L）和5．3倍（Mn~(2+)量为6．0~14μg/L）,相对标准偏差为0．5％,检出限为5．6×10~(-8)g/L,可用于酒样和谷物制品中锰的测定。     

锌试剂和高碘酸钾反应动力学测定超痕量锰

在 p H4.74的 HAc- Na Ac缓冲溶液中 ,以氨三乙酸为活化剂 ,KIO4 氧化锌试剂的反应受 Mn( )的催化加速 ,从而建立了测定超痕量锰的新方法。研究了影响反应速率的条件 ,测定了反应的表观活化能及表观速率常数。该法的检出限为 2 .4× 1 0 -11g/m L,测定范围是 0 .0～ 2 0 ng/1 0 m L。可用于蒸馏水中超痕量锰及大豆、面粉中痕量锰的测定     

二溴羧基偶氮胂催化动力学光度法测定痕量锰(Ⅱ)的研究

在 HAc- Na Ac介质中 ,在氨三乙酸存在下 ,表面活性剂溴化十六烷基三甲胺对锰 ( )催化高碘酸钾氧化二溴羧基偶氮胂的褪色反应有强烈的增敏作用。研究了反应的最佳条件 ,建立了动力学光度法测定痕量锰的新方法。该方法的检出限为4.1 0× 1 0 - 11g/m L,线性范围 0～ 1 4 μg/L,用于食品及铝合金中痕量锰 ( )的测定 ,结果令人满意。     

亚临界水萃取-高效液相色谱法测定聚碳酸酯水杯中双酚A和苯酚的迁移量

建立了亚临界水萃取-高效液相色谱同时测定聚碳酸酯(PC)水杯中双酚A和苯酚迁移量的方法。选择萃取温度120 ℃、萃取压力6.89 MPa(1000 psi)、静态萃取时间1 h、萃取1次对11种样品进行测定。双酚A的迁移量为6.81～11.16 μg/g。5种样品中未检出苯酚,其余样品中苯酚迁移量为3.25～6.08 μg/g。在优化的测定条件下,双酚A和苯酚在8 min内达到基线分离。双酚A和苯酚分别在0.05～20 mg/L和0.02～20 mg/L范围内线性关系良好,相关系数(r)均大于0.9997,检出限分别为7.6 μg/L和2.0 μg/L。日内及日间的重复性(以RSD计)分别小于5.21%及11.63%。传统的浸提法结果表明长时间浸提会使PC材料发生微弱水解。相比传统的浸提法,该方法的萃取效率提高了49～106倍。该方法简便、快速、环保,可用来测定PC水杯中双酚A和苯酚的迁移量。     

基于BSTFA衍生/GC-MS与DLLME/HPLC的老化变压器油中短碳链羧酸的分析

以N,O-双(三甲基硅烷基)三氟乙酰胺(BSTFA)为硅烷化试剂,建立了衍生化气相色谱-质谱(GC-MS)测定老化变压器油中短链羧酸的定性分析方法;并建立了分散液液微萃取/高效液相色谱(DLLME/HPLC)测定其中甲酸、乙酸和糠酸的定量分析方法。结果表明:以乙腈为萃取剂,BSTFA为硅烷化试剂,60℃下反应60 min后进行GC-MS测定,在老化变压器油中检出甲酸、乙酸和糠酸等14种短碳链羧酸。以水为萃取剂对标准油样中的甲酸、乙酸和糠酸进行萃取,取水萃取相直接进行HPLC测定。在最佳条件下,甲酸、乙酸在0.05～50.0 mg/L及糠酸在0.01～2.0 mg/L质量浓度范围内线性良好,相关系数(r)大于0.998,检出限(LOD)分别为36.1、47.3、7.0μg/L,相对标准偏差(RSD)分别为2.4%、3.3%和3.6%,3种羧酸的富集倍数为8～10倍。老化油样的加标回收率为91.7%～107%。该法简单有效,为变压器油纸绝缘老化特征量的正确使用和羧酸类物质对油纸绝缘老化影响的研究提供了数据。     

固相萃取-离子色谱法测定饮用水中的痕量卤代乙酸

建立了固相萃取-离子色谱(SPE-IC)测定饮用水中痕量卤代乙酸(HAAs)(包括一氯乙酸、二氯乙酸、三氯乙酸、一溴乙酸和二溴乙酸)的方法。固相萃取采用LiChrolut EN SPE柱来进行痕量待测物的预浓缩（25倍）和基体杂质的消除,用NaOH(10 mmol/L)洗脱;色谱分离采用亲水性、高容量、氢氧化物选择型阴离子交换柱Dionex IonPac AS16(250 mm×4 mm i.d.),以NaOH为流动相进行浓度梯度淋洗,淋洗速度为0.8 mL/min,电导检测,进样量为500 μL。结果表明,用SPE-IC法测定HAAs,一溴乙酸的检测限为12.5 μg/L,其余4种HAAs的检测限为0.38~1.69　μg/L。该法可实现对饮用水中痕量卤代乙酸的测定。     

高碘酸钾氧化刚果红和萘酚绿B褪色催化动力学光度法测定茶叶中的微量锰

在NH3-NH4Cl缓冲溶液介质中,以氨三乙酸为活化剂,利用微量Mn(Ⅱ)对KIO4氧化刚果红和萘酚绿B的褪色反应具有催化作用,通过测量480nm和720nm波长处催化和非催化体系吸光度的变化,建立了双波长双指示剂催化动力学光度法测定微量Mn(Ⅱ)的新方法。方法的线性范围为2.4～40μg/L,检出限为0.301μg/L。用于茶叶中锰的测定,加标回收率为96.2%～101.4%。     

液相色谱-串联质谱法测定生活饮用水中4种卤代乙酸的含量

提出了液相色谱-串联质谱法测定生活饮用水中二氯乙酸、三氯乙酸、一碘乙酸和二碘乙酸等4种卤代乙酸含量的方法。取0.5 mL过滤后的水样,与0.5 mL乙腈混合。以Torus DEA色谱柱为固定相,以体积比10∶90的含1.0 mmol·L^-1乙酸铵的2.0%(体积分数)氨水溶液-乙腈混合液为流动相进行等度洗脱。分离后的4种目标物经电喷雾离子源负离子模式扫描,采用多反应监测模式进行检测,外标法定量。结果显示：4种卤代乙酸的质量浓度在5～100μg·L^-1内与定量离子峰面积呈线性关系,检出限(3S/N)为0.3～3.0μg·L^-1;对自来水水样进行3个浓度水平的加标回收试验,回收率为70.1%～114%,测定值的相对标准偏差为(n=6)为0.90%～5.8%;方法用于10份末梢水分析,其中一碘乙酸、二碘乙酸和三氯乙酸均未检出,有8份样品检出二氯乙酸,检出量为2.0～4.4μg·L^-1。     

催化动力学光度法测定痕量锰

在活化剂氨三乙酸存在下,基于锰(Ⅱ)催化高碘酸钾氧化亮绿SF的反应,建立了测定痕量锰(Ⅱ)的催化动力学光度法。在优化的实验条件下,测定锰(Ⅱ)的线性范围为0.6~6.0 ng/mL,检出限为6.0×10-11g/mL,相对标准偏差为2.5%(n=9)。该法灵敏度高,选择性和重现性较好,已用于测定饮用水和葡萄酒试样中的痕量锰。     

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.     

探究“铁的锈蚀条件”实验创新设计

设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。