苯磺酰甘氨酸稀土(Pr、Yb)对种子、幼苗的生物效应

合成了Pr、Yb的苯磺酰化甘氨酸配合物,观测了它们对水稻幼苗初期生长的影响以及对油菜种子萌发和幼苗生长情况。结果表明,适宜含量的该类配合物可促进种子萌发的启动,并对种苗根系和幼苗的生长有明显促进作用,并以2.5×10-6~5.0×10-6含量范围效果最佳。     

Folin-Ciocalteu比色法测定石榴叶中多酚的含量

正石榴是石榴科石榴属落叶灌木,诸多研究表明,其果皮、种子、果汁、茎、叶等均含有各种对人体有益的营养成分,具有一定的保健和药用价值[1-6]。其中石榴叶很早就被发现具有收敛止泻、解毒杀虫的功效,在埃及作为传统药材[7]。现代研究显示,石榴叶还具有调节血脂水平、清除自由基、抗氧化、提高免疫力等作用[7-8],且这些活性效用均与其所富含的多酚类物质相关。但是,目前鲜见对石榴叶中多酚含量测定的报道,研究者多将焦点集中在石榴皮中多     

均三溴偶氮胂分光光度法测定植物体及种子中铈组稀土

随着稀土元素在农业上应用研究的深入,需要对种子、植株中微量铈组稀土进行测定。目前已有人用中子活化法^[1]萃淋树脂分离富集光度法^[2]进行测定。由于植物中钙等干扰元素的含量高(钙含量为0.1—5 mg/g),给直接光度法测定带来困难。     

电化学氢化物发生-原子荧光光谱法测定尿中砷的含量

正砷及其化合物广泛存在于土壤、水、空气、植物及动物等环境中,都有可能被人体吸收,从而引起砷中毒,砷含量高时有可能致人死亡,故对人体尿砷含量的检测有重要意义。目前,测定砷含量的方法有分光光度法[1]、氢化物发生-原子吸收光谱法[2]、原子荧光光谱法[3-4]、电感耦合等离子体原子发射光谱法[5]和电感耦合等离子体质谱法[6]等,其中,氢化物发生原子荧光光谱法具有仪器便宜,样品前处理简     

油菜籽中主要硫甙的分离提纯

用柱色谱方法从甘蓝型油菜籽中分离提纯了1-硫［(1Z)-3-羟基-1-［(磺酸基)亚氨基］-4-戊烯基］-1-硫代-β-D-葡萄糖钾盐(progoitrin)。用甲醇溶液提取菜籽中的硫甙,得到粗提物;粗提物经酸性氧化铝色谱柱与反相C18硅胶柱进一步分离提纯,得到纯品。对纯品进行紫外光谱、红外光谱、核磁共振氢谱、质谱和元素分析,测得的数据与文献值相符。用高效液相色谱测得硫甙提取物的纯度为99%。该方法操作简便,得到的硫甙样品纯度高,是一种有价值的硫甙提取方法,具有良好的应用前景。     

低氧低分压环境下聚氨酯泡沫塑料富集-电感耦合等离子体质谱法测定地质样品中微量金

金具有良好的稳定性,不容易迁移富集,在岩石矿物中含量较低。微量金的分析方法主要有化学光谱法[1-2]、石墨炉原子吸收光谱法[3-4]、分光光度法[5-6]和电感耦合等离子体质谱法[7-8]等。化学光谱法和分光光度法存在流程长、工作强度大等缺点;石墨炉原子吸收光谱法稳定性差、线性范围窄,不适合     

固相萃取-气相色谱-质谱法测定粮谷中敌草快的残留量

<正>敌草快的化学名称为1,1′-亚乙基-2,2′-联吡啶二溴盐,是一种非选择性触杀型的除草剂,也是一种接触性的干燥剂,适用于农田除草,还可作为种子植物的干燥剂[1-2]。目前,已有文献报道的敌草快的检测方法有高效液相色谱法[3-4]、高效液相色谱-串联质谱法[5-6]、分光光度法[7]以及气相色谱-串联质谱     

国家标准方法测定土壤中总砷消解方法的改进

正随着现代工农业的快速发展,城镇和农村生活水平不断提高,土壤中砷的污染日益严重。准确、快捷、有效地测定土壤中砷的含量,成为近年来土壤分析方法研究的重要内容。目前土壤样品中砷前处理方法主要有硝酸-硫酸-高氯酸混合酸电热板消解法[1]、盐酸-硝酸-水(3+1+4)混合液水浴消解法[2-4]、微波消解法[5-7]和程序控温石墨消解法[8]等。     

溴邻苯三酚红双波长分光光度法测定铝合金中铜北大核心CSCD

在铝合金中加入铜,能增加铝合金的强度,提高铝合金的应力腐蚀抗力,因此测定铝合金中铜的含量具有重要意义。溴邻苯三酚红是一种重要的显色试剂,已用于羟自由基[1]、碘[2]、蛋白质[3]、乙二胺四乙酸（EDTA）[4]、钼[5]、硒[6]、铌[7]、铝[8]等的测定。双波长分光光度法在光度分析中的应用较为广泛[9-10]。     

肥皂草素Saporin-S6二级结构的圆二色光谱及激光喇曼光谱法表征

肥皂草素是从石竹科植物肥皂草 (Saponaria officinalis)的种子中提取的一种单链核糖体失活蛋白(sc RIP) ,它可选择性地作用于真核细胞的核糖体和原核细胞裸露的 r RNA使其脱嘌呤 ,从而抑制蛋白质的合成 [1] .核糖体失活蛋白种类繁多 ,性质稳定 ,制备安全简便 ,与单克隆抗体结合后所制备的单链免疫毒素在肿瘤治疗和骨髓移植等方面有着广泛的应用前景[2 ] .Stirpe等[1] 首次分离到肥皂草毒蛋白 ,并证明其为不含糖基的单链 RIP.SO-6是种子中含量最丰富的核糖体失活蛋白 [3] ,且具有特殊的稳定性[4 ] .肥皂草素在医学上的应用十分广泛 ,…     

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.     

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。     

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^-。     

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.     

解决能源问题的新途径——光解水制氢的研究

面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。