电感耦合等离子体质谱法测定有机肥料中砷、镉、铅、铬、汞的含量

提出了用微波消解-电感耦合等离子体质谱法测定有机肥料中砷、镉、铅、铬、汞等5种元素的方法。有机肥料样品(0.200 0~0.500 0g)加入硝酸10mL和过氧化氢溶液1mL,按程序升温微波消解,将消解液蒸发至2mL,用硝酸(1+99)溶液定容至50mL。用电感耦合等离子体质谱法测定上述样液中的砷、镉、铅、铬、汞等元素。各元素的检出限(3.3s/k)为0.015~0.040mg·kg~(-1),测定值的相对标准偏差(n=6)均小于5.0%。按标准加入法进行回收试验,测得回收率在98.0%~101%之间。     

石墨消解-电感耦合等离子体光谱法测定土壤中全硼

建立聚乙烯离心管石墨消解-电感耦合等离子体光谱仪测定土壤中硼含量的方法。将土壤样品风干，粉碎至粒径不大于150μm，称量0.1 g土壤样品于50 mL离心管中，加入3 mL盐酸-硝酸-氢氟酸混合液（体积比为1∶1∶1）作为消解试剂，在石墨消解炉中于105℃消解45 min，将消解溶液静置至室温，用去离子水定容至50 mL，取上清液，采用电感耦合等离子体光谱法进行测定。硼的质量浓度在0～2.5μg/mL范围内与光谱强度的线性关系良好，线性方程为y=97 952x-326.14，相关系数为0.999 6，方法检出限为1.0 mg/kg。用该方法对国家标准物质进行测定，测定结果的相对标准偏差为0.79%～1.72%(n=12)，样品加标回收率为99.1%～100.7%。     

微波消解-电感耦合等离子体质谱法测定土壤中9种重金属元素

建立微波消解-电感耦合等离子体质谱法测定土壤中的钒、铬、钴、镍、铜、锌、钼、镉、铅9种重金属元素。采用硝酸-氢氟酸-过氧化氢三酸体系微波消解土壤样品后,加入高氯酸于赶酸仪中对样品进行处理,定容至50 mL容量瓶中,混匀至澄清,取分液用电感耦合等离子体质谱仪对土壤中的9种重金属元素进行定量分析。探讨了称样质量、样品处理试剂、干扰效应、溶液酸度对测定结果的影响,各元素的质量浓度在0～100.0μg/L范围内与其对应的信号强度线性关系良好,相关系数为0.999 2～0.999 9,方法检出限为0.013～1.0 mg/kg。对土壤标准物质进行测定,测定值的相对标准偏差为0.82%～4.73%(n=6),测定值与标准值相吻合,相对误差为-12.1%～11.11%。样品处理过程中未使用盐酸,该法适于土壤中重金属元素的含量测定。     

微波消解-电感耦合等离子体质谱(ICP-MS)法同时测定土壤中11种金属元素

称取0.25g样品加入5 mL硝酸和2 mL氢氟酸,用微波消解技术对样品进行前处理.以Re作为As、Pb、Tl的内标,Rh作为Cd、Co、Cr、Ni的内标,Bi作为Be、Cu、Zn的内标,Tb作为V的内标,建立了KED模式下微波消解电感耦合等离子体质谱(ICP-MS)法同时测定土壤中Be、As、Cd、Co、Cr、Cu、...     

微波消解-电感耦合等离子体发射光谱法同时测定土壤中主次金属元素

建立微波消解-电感耦合等离子体发射光谱法同时测定土壤中多种主次元素的分析方法。采用硝酸-氢氟酸-双氧水体系在微波消解仪中消解土壤样品,待消解完成后加入高氯酸驱赶氢氟酸,盐酸溶解盐类物质,将土壤中所有元素的矿物晶格破坏使待测溶液全部进入试液,采用电感耦合等离子体发射光谱进行测定。通过筛选合适分析谱线和合理设置背景扣除位置提高样品分析中的精密度和准确度。选用国家土壤标准物质进行方法验证,绝大多数实验结果与标准值吻合,RSD小于5%。本方法具有同时测定土壤样品多种元素、试剂用量少、操作简单等优点,表明该方法适合大批量土壤中主次元素的快速检测。     

微波消解-ICP-MS法同时测定木薯淀粉中铅、铜、镉、砷、汞的含量

用硝酸-过氧化氢溶液(3+3)作为消解剂,微波消解法处理木薯淀粉等样品,采用电感耦合等离子体质谱法,选择适合的同位素元素,运用碰撞池技术(CCT)降低元素Cu、As的多原子离子干扰,测定样品溶液中Pb、Cu、Cd、As、Hg等元素的含量,各元素线性相关系数为0.9997 ～0.9999,元素的检出限(3sd)分别为pb...     

微波消解-电感耦合等离子体质谱法同时测定有机肥料中9种有毒有害元素的含量

提出了微波消解-电感耦合等离子体质谱法(ICP-MS)同时测定有机肥料中As、Cd、Co、Cr、Ni、Pb、Sb、Tl、V等9种有毒有害元素含量的方法。取0.10 g有机肥料样品于聚四氟乙烯微波消解罐中,以2.5 mL盐酸、7.5 mL硝酸和2.0 mL氢氟酸为混合酸进行微波消解。消解结束后,于140℃赶酸,然后加入1.0 mL 50%(体积分数)硝酸溶液,再用水定容至50 mL,摇匀,过滤,取滤液待测,在线加入混合内标溶液。结果表明：9种元素标准曲线的线性范围均为2～100μg·L^-1,方法检出限(3s)为0.59～66.75μg·kg^-1;按照标准加入法对典型有机肥料样品进行回收试验,9种元素测定值的相对标准偏差(n=7)为2.0%～3.5%,回收率为81.5%～112%。     

电感耦合等离子体质谱法测定风电机组齿轮油中铅、砷、铬、镉的含量北大核心CSCD

取齿轮油样品0.300 0g,加入硝酸15mL,过氧化氢5mL及高氯酸1mL,按程序升温加热模式进行微波消解。所得消解后的溶液于180℃蒸发至近干,加水定容至20mL。采用电感耦合等离子体质谱法测定此溶液中铅、砷、铬、镉的含量,以内标法补偿基体效应。铅、砷、铬、镉的质量浓度在1.00～50.0μg·L-1范围内与其对应的信号强度呈线性关系,检出限(3S/N)依次为0.05,0.006,0.04,0.003μg·L-1。按标准加入法进行回收试验,回收率为81.3%～96.4%,测定值的相对标准偏差(n=6)为1.2%～4.3%。     

基于石墨消解法测定海洋沉积物中7种重金属的含量

鉴于目前常用的海洋沉积物中重金属测定的消解方法存在工作效率低、操作复杂、交叉污染、人员危险性高等问题,通过比对和参考现行规范、标准和文献资料中海洋沉积物重金属的不同消解方法,提出了全自动石墨消解海洋沉积物的方法,并以原子荧光光谱法测定汞和砷的含量,以电感耦合等离子体质谱法测定铜、铅、锌、镉、铬的含量。以6 mL盐酸、2 mL硝酸和8 mL水为消解酸,于100℃消解0.2 g样品1.5 h;消解结束后,冷却至室温,用水定容至50 mL,按照原子荧光光度计的工作条件测定汞和砷的含量。以5 mL盐酸、5mL硝酸为消解酸,先于120℃消解0.2 g样品1 h;然后加入2 mL硝酸、5 mL氢氟酸和2 mL高氯酸,于180℃继续消解4 h;消解结束后,冷却至室温,用水定容至50 mL,按照电感耦合等离子体质谱仪的工作条件测定铜、铅、锌、镉、铬的含量。结果表明：汞、砷标准曲线的线性范围分别在1.00μg·L^-1以内和10.0μg·L^-1以内,铜、铅、锌、镉、铬标准曲线的线性范围在100μg·L^-1以内,汞、砷、铜、铅、锌、镉、铬的检...     

电感耦合等离子体原子发射光谱法测定河流和湖泊沉积物中11种重金属元素含量

提出了用微波消解-电感耦合等离子体原子发射光谱法测定河流和湖泊沉积物中11种重金属元素(银、镉、钴、铬、铜、锰、镍、铅、锑、钒和锌)的方法。沉积物样品(0.100 0~0.500 0g)加入硝酸6mL,盐酸2mL,氢氟酸2mL,按程序升温微波消解,将消解液于130~140℃蒸发至近干,加水溶解残渣并定容至50mL。此溶液供电感耦合等离子体原子发射光谱法同时测定11种重金属元素含量,并选择了合适的分析谱线。光谱干扰运用背景扣除予以校准。测得各元素的检出限(3s)为0.20~2.00mg·kg~(-1)。以沉积物样品为基体,按标准加入法进行回收试验,测得回收率在81.6%~112%之间,相对标准偏差(n=6)均小于6.0%。按上述方法测定CRM(GBW 07360,GBW 07307a),测定值与认定值一致。     

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。