微波消解—火焰原子吸收法测定豌豆中微量元素锰、锌、铜、铁的含量

探讨了采用微波消解法处理样品,以FAAS法在同一体系中测定豌豆中微量元素锰、锌、铜、铁的方法,包括硝酸、过氧化氢的用量以及消化时间长短对实验的不同影响和在同一体系中锰、锌、铜、铁的彼此干扰情况。在选定的条件下,测得豌豆中锰、锌、铜、铁的含量分别为:锰10.05 mg/g、锌9.48 mg/g、铜3.06 mg/g、铁18.30 mg/g,回收率96.8%~98.9%。     

羊水中锌铜铁锰钙的测定

对61例妊娠晚期(孕34～40周)孕妇羊水进行了微量元素锌、铜、铁、锰及常量元素钙的测定.测定结果依次为:锌0.938±0.631 mg/L,铜0.178±0.156 mg/L,铁1.471±0.706 mg/L,锰0.047±0.017 mg/L,钙56.4±22.9 mg/L,为羊水微量元素研究提供了参考.     

微波消解-电感耦合等离子体发射光谱法测定固体生物质燃料中8种元素

建立电感耦合等离子体发射光谱法同时测定固体生物质燃料中钾、钠、钙、镁、砷、铜、铁、锰8种元素的含量。样品采用5 mL硝酸溶液和2 mL过氧化氢溶液进行微波消解,在选定的仪器工作条件下进行测定。钠、钙、镁、砷、铜、铁、锰的质量浓度在0～5.0 mg/L,钾的质量浓度在0～50.0 mg/L范围内与光谱强度具有良好的线性关系,相关系数均大于0.999,方法检出限为0.002～0.022 mg/L。样品的加标回收率为91.9%～108.2%,测定结果的相对标准偏差为2.1%～6.8%(n=6)。该方法简便、快速、高效且准确,适用于固体生物质燃料中钾、钠、钙、镁、砷、铜、铁、锰的测定。     

电感耦合等离子体光谱法(ICP-AES)测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量

针对银精矿样品复杂,难消解的特点,研究了不同酸溶法和碱熔法对样品的消解情况,建立了硝酸,盐酸,氢氟酸,高氯酸消解银精矿的方法。根据元素灵敏度和抗干扰性,选定各元素的测定波长。通过酸溶样和碱熔样测定结果比对,验证了方法准确性。建立了四酸消解-电感耦合等离子体光谱法测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的方法,元素的线性相关系数均在0.9999以上。通过共存元素干扰实验,确定了银精矿中高含量元素(铜、铅、锌、铁、锑、铋等)对测定元素结果没有影响。方法检出限：Cu 0.0063 mg/L, Pb 0.0159 mg/L ,Zn 0.0090 mg/L,As 0.0192 mg/L, Cd 0.0093 mg/L ,Ca 0.0084 mg/L, Mg 0.0075 mg/L, Mn 0.0081 mg/L。测定下限：Cu 0.0105mg/L,Pb 0.0265 mg/L, Zn 0.0150 mg/L, As 0.0320 mg/L, Cd 0.0155 mg/L, Ca 0.0140 mg/L, Mg 0.0125 mg/L,Mn 0.0135 mg/L。3个样品的相对标准偏差在0.87%~3.56%之间,加标回收率在95.00%~103.56%之间。方法流程短,操作简单,快速,灵敏度和再现性高,结果准确可靠,可以满足银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的测定。     

钙、镁、铁、铝离子对土壤中总氟化物检测干扰的消除

建立钙、镁、铁、铝离子对离子选择电极法检测土壤总氟化物干扰的消除方法。通过对含不同浓度水平钙、镁、铁、铝离子的土壤样品中总氟化物进行测试,明确了在总离子强度调节缓冲溶液共存下钙、镁、铁、铝离子对土壤提取液中总氟化物检测结果存在负干扰。通过测试10种土壤样品总氟化物提取液中干扰最强的背景铝含量,对其中土壤提取液中铝离子质量浓度大于10.0 mg/L的3种土壤样品进行加标回收试验,结果表明了土壤总氟化物含量为327～926 mg/kg范围内,当样品提取液中的铝离子含量为50～100 mg/L时,通过减少提取液取样体积为5.00 mL并增加柠檬酸三钠总离子强度缓冲溶液体积至15.0 mL的方法可将加标回收率由56.4%～78.3%优化至94.7%～104.0%;当加入Ca~(2+),Mg~(2+),Fe~(3+)质量浓度为200～300 mg/L,加标回收率由63.1%～77.6%优化为92.4%～105.0%。用优化后的方法测定土壤总氟化物含量为246～2 240 mg/kg的5种标准样品,测试结果与标准值一致。该方法能有效地消除土壤样品总氟化物测定中含钙、镁、铁离子质量浓度为200～300 mg/L,铝离子质量浓度为50～100 mg/L而产生的干扰,具有良好的适用性。     

火焰原子吸收光谱法测定木瓜中7种微量元素的含量

采用火焰原子吸收法测定光皮木瓜中钙,铜,铁,硒,锌,锰,镁等微量元素的含量。优化了仪器工作条件,利用标准曲线法对待测样品进行定量分析。在设定的浓度范围内,7种元素的质量浓度与吸光度呈良好的线性关系,相关系数为0.992 9～0.999 4,7种元素的检出限为0.211～9.268 mg/L。对样品进行7次重复测定,测定结果的相对标准偏差均小于3.0%,加标浓度为1.000 0～10.010 0 mg/L时,加标回收率为96.51%～104.55%。该方法具有操作简单、干扰少等优点,为木瓜的开发提供了科学依据。     

广西黑老虎中微量元素测定

采用原子吸收光谱法测定广西黑老虎中锰、铁、铜、锌、镁、钙等6种微量元素，并与笋干和16种蔬菜中6种微量元素含量进行比较，结果发现，黑老虎中锰、铁、铜、锌、镁、钙等6种微量元素含量均较高，其中锰、钙、铜、锌含量高于笋干，锰、铁、铜、锌含量远远高于16种蔬菜中微量元素的含量，钙含量高于部分蔬菜含量。提示广西黑老虎中含有丰富的人体所需微量元素，作为药用植物，具有极高的药用价值。     

癫痫与微量元素

评论了微量元素锌,铜,铁,锰与癫痫的关系。癫痫患者血浆中锌、铜、铁含量比正常对照组增高,锰含量降低。锌／铜比值较正常对照组明显降低。而癫痫患者发锌,铁含量比正常人对照组升高,发铜,锰含量降低。     

电感耦合等离子体原子发射光谱法同时测定不锈钢中的11种元素

建立电感耦合等离子体原子发射光谱法同时测定不锈钢中硅、锰、磷、铬、镍、钼、钴、钒、钛、铜、铝11种元素含量的方法。样品采用盐酸溶液溶解,硝酸氧化,在优化的实验条件下,用电感耦合等离子体原子发射光谱法测定各元素含量。磷的质量浓度在0～5 mg/L范围内,钛、铝、钴的质量浓度在0～10 mg/L范围内,钒的质量浓度在0～15mg/L范围内,铜、硅、钼的质量浓度在0～20 mg/L范围内,锰的质量浓度在0～50 mg/L范围内,镍的质量浓度在0～80 mg/L范围内,铬的质量浓度在0～100 mg/L范围内与光谱强度呈良好的线性关系,相关系数均大于0.998,方法检出限为0.002～0.035 mg/L。测定结果的相对标准偏差均小于2%(n=6),加标回收率为97.9%～105.6%.该方法快速、准确,适用于实际生产中不锈钢样品的批量检测。     

微波消解-火焰原子吸收光谱法测定中药女贞子中9种金属元素

用微波消解法处理样品,用硝酸-过氧化氢(4+1)混合溶液作为消解剂进行微波消解,火焰原子吸收光谱法测定了中药女贞子中钙、镁、钾、钠、铁、锶、锰、铜和锌元素含量。9种元素检出限(3S/N)在0.000 6~0.024 8 mg.L-1之间,回收率在93.0%~107.3%之间,相对标准偏差(n=10)在0.86%~4.39%之间。试验结果表明:女贞子中钾、钙、镁、铁、钠、锌、锰、铜和锶质量分数分别为16 940,1 790,1 640,467.8,116.0,24.5,15.0,9.6,1.9μg.g-1,锌与铜含量的比值为2.55。由此可见,女贞子中钙、镁、钾元素含量丰富,铁含量也较高。为探讨中药金属元素种类及含量与治疗心血管疾病的关系等提供有用数据。     

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。