纤维素衬层压片-X射线荧光光谱法测定砂岩型铀矿中9种主次元素

目的是采用粘结性强、腐蚀性低有机纤维素替换粉末压片法中硼酸衬层,降低硼酸衬层在样品分析过程中受热挥发,分散的硼酸粉末附着于仪器金属部件、滤光片、准直器,硼酸粉尘累积,增加仪器维护保养成本甚至会影响仪器运行和检测结果等不良影响。方法研究其有机纤维素作为衬层可能性及对样品检测结果的影响,微晶纤维粉改善砂岩型铀矿样品的过程中会出现样品粘结性差、分层和裂纹的效果。结果该方法测定砂岩型铀矿中9种主次元素的精密度(RSD,n=11)为0.34-4.76%,准确度为0.06-5.52%,相较于硼酸衬层和未添加辅助粘结剂样品的测定值,应用格拉布斯法检验各元素统计量G均在1.25-1.40%之间。结论采用羟甲基纤维素作为衬层可用于砂岩型铀矿中主次元素的测定,添加微晶纤维素0.5g可改善矿石粘结性能,提升实验制备样片的稳定性,降低了样品分析对仪器金属部件及检测效果的影响。     

X射线荧光光谱法测定钒铁合金中主次元素含量

用熔融制样法将钒铁合金样品在铂金坩埚中与四硼酸锂和偏硼酸锂熔融,熔体在铂金坩埚中自动成型,用X射线荧光光谱法测定钒铁合金中钒、硅、锰、铝和磷等主次元素含量。经试验求得熔融时,四硼酸锂、混合溶剂(四硼酸锂∶偏硼酸锂=67∶33)和样品的最佳质量比为30比5比1。各元素的检出限在12.4～51.2μg.g-1之间。方法用于标准样品分析,测定值与认定值相符。     

X射线荧光光谱法测定白云石中12种元素的含量

采用X射线荧光光谱法测定白云石中钠、镁、铝、硅、磷、硫、钾、钙、锰、铁、钛、锌等12种元素的含量。样品以四硼酸锂和偏硼酸锂为熔剂和溴化锂为脱模剂于1 050℃熔融,样片用于X射线荧光光谱分析。以GBW 07114、GBW 07216A、GBW 07217A、YSBC 11703-1995、YSBC28722-1993、YSBC 28723-1993等标准物质为基础制作工作曲线。优化了各元素的基体校正数学模型。对白云石样品重复测定11次,测得其相对标准偏差(n=11)在0.2%~7.3%之间。方法用于白云石标准样品的分析,所得结果与认定值相符。     

X射线荧光光谱法测定钒钛磁铁矿中的主次量元素

采用X射线荧光光谱法测定钒钛磁铁矿中铁、钛、硅、铝、锰、钒、钙、镁等8种主次量元素。样品以四硼酸锂、偏硼酸锂和氟化锂(质量比为4.5比1比0.4)为熔剂,脱模所得熔块用于X射线荧光光谱分析。以GBW 07224、GBW 07225、GBW 07227、YSBC 19701-76、GSB 03-2584-2010、YSBC 19722-2011等6种标准物质和光谱纯二氧化硅、氧化钙、氧化铝、五氧化二钒、二氧化钛为基础制作校准曲线。优化了各元素的基体校正数学模型。各元素的检出限在3.79~39.06mg·kg-1之间。对钒钛磁铁矿标准样品GBW 07225重复测定10次,测得其相对标准偏差(n=10)在0.83%~2.9%之间。方法用于钒钛磁铁矿标准样品GBW 07225,GBW 07227的分析,所得结果与认定值相符。     

电感耦合等离子体原子发射光谱法测定水晶泥玩具中硼酸和硼酸盐

建立电感耦合等离子体原子发射光谱快速测定水晶泥玩具中硼酸和硼酸盐的分析方法。以纯水为溶剂,采用水浴震荡萃取方式提取样品中硼酸和硼酸盐,外标法定量硼元素,硼酸和硼酸盐的含量以硼酸的形式表示。硼的质量浓度在0.1～5 mg/L范围内与信号强度呈良好的线性关系,线性相关系数(r)为0.999 8,硼酸的检出限为0.007mg/L,定量限为0.021 mg/L。水晶泥玩具样品中硼酸和硼酸盐在3个浓度水平的加标回收率为84.6%～108.4%,测定结果的相对标准偏差小于5%(n=5)。该方法检测快速,适用于水晶泥玩具样品中硼酸和硼酸盐的检测。     

一体化碰撞反应(iCRC)-电感耦合等离子体质谱(ICP-MS)法测定地质样品中痕量稀土元素

钡以及轻稀土元素氧化物对中、重稀土元素的干扰一直是质谱测试中存在的问题。建立了石墨粉垫底碳酸钠-硼酸混合熔剂熔融前处理样品,以103 Rh为内标校正,一体化碰撞反应-电感耦合等离子体质谱(ICP-MS)法测定地质样品中稀土元素含量的方法。探讨了碳酸钠-硼酸混合熔剂熔融前处理样品注意事项、碰撞模式下碰撞气流量和离子透镜的参数优化、干扰校正实验等问题,采用国家标准物质GBW07403、GBW07405、GBW07427、GBW07429验证,实验结果表明,各元素线性关系良好,相关系数均大于0.999,方法检出限在0.01～0.03mg/kg,相对误差为0.13%～7.1%,相对标准偏差为0.79%～6.6%,测定结果与标准值相吻合。对实际样品分析,得到平滑的球粒陨石归一化的稀土元素配分曲线,证明测定结果是合理可信的。方法熔剂用量少,过程空白低,对器皿的侵蚀小,直接加热浸取,简化了操作过程,适用于大批量地质样品中稀土元素的测定。     

一体化碰撞反应 (iCRC)-电感耦合等离子体质谱法测定地质样品中痕量稀土元素

钡以及轻稀土元素氧化物对中、重稀土元素的干扰一直是质谱测试中存在的问题。建立了石墨粉垫底碳酸钠-硼酸混合熔剂熔融前处理样品,以_¹⁰³Rh为内标校正,一体化碰撞反应-电感耦合等离子体质谱仪法测定地质样品中稀土元素含量的方法。探讨了碳酸钠-硼酸混合熔剂熔融前处理样品注意事项、碰撞模式下碰撞气流量和离子透镜的参数的优化、干扰校正试验等问题,采用国家标准物质GBW07403、GBW07405、GBW07427、GBW07429验证,实验结果表明,各元素线性关系良好,相关系数均大于0.999,方法检出限在0.01～0.03mg/kg之间,相对误差为0.13%～7.1%,相对标准偏差为0.79%～6.59%,测试结果与标准值相吻合。对实际样品分析,得到平滑的球粒陨石归一化的稀土元素配分曲线,证明测定结果是合理可信的。该方法熔剂用量少,过程空白低,对器皿的侵蚀小,直接加热浸取,简化了操作过程,适用于大批量地质样品中稀土元素的测定。     

熔融制样-X射线荧光光谱法测定火力发电厂烟气脱硫石膏中主次量元素

建立了熔融制样-X射线荧光光谱法(XRFS)测定火力发电厂烟气脱硫石膏中9种主次量元素(以元素氧化物形式表示)的方法,并用正交试验优化了熔融制样条件。将样品与四硼酸锂-偏硼酸锂混合熔剂(质量比12∶22)按1∶8的质量比混合,加入40 g·L~(-1)溴化锂溶液0.6 mL,在自动燃气熔样机上于1 050℃熔融4.5 min,冷却脱模后即得玻璃样片,在优化的XRFS条件下测定。采用硫酸钙、氧化钙、石膏成分分析标准物质和煤灰成分分析标准物质配制的标准样品系列制作校准曲线,并用理论α系数法校正基体效应。结果显示:9种主次量元素氧化物线性相关系数均大于0.990 0,检出限为0.006 4%～0.059 9%。方法用于2个烟气脱硫石膏样品的分析,2次平行测定值的差值均小于国家标准GB/T 5484-2012规定的重复性限,且测定值和GB/T 5484-2012的基本一致。     

波长色散X射线荧光光谱法测定钴精矿中钴、铜和锰

采用高纯氧化物经四硼酸锂和偏硼酸锂熔融制备人工标准样品,以氧化镱为内标,制作校准曲线,建立了波长色散型X射线荧光光谱法测定钴精矿中钴、铜、锰元素的分析方法.重点研究了混合熔剂、试样稀释比、氧化剂和内标选择、方法检出限、方法准确度和精密度等,结果表明,各元素校准曲线线性范围宽,相关系数均大于0.999,钴、铜、锰元素检出...     

一次消解土壤样品测定汞、砷和硒

建立了测定土壤中3种挥发性元素(汞、砷、硒)的一次消解方法,确定以程序控温石墨自动消解仪+王水-氢氟酸-硼酸络合敞开体系为最佳消解体系,采用氢化物发生-原子荧光光谱法(HG-AFS)分别测定同一消解液中汞、砷、硒的含量.采用国家标物中心有证标准物质土壤环境样品GSS-1~GSS-8进行了方法验证,结果均符合标准偏差的允许范围.此消解方法相比于现行标准方法,避免了针对各元素的分次处理,简化了消解步骤,节省了前处理时间,减少了试剂消耗,提高了实验效率,适用性广、灵敏度高、检出限低,尤其适合批量样品的微量/痕量元素分析,可作为一种大规模土壤样品中重金属污染监测和治理的快捷方法.     

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。