电感耦合等离子体质谱（ICP-MS）法测定垃圾焚烧飞灰中的重金属

基于全自动消解仪优化程序,以HNO3-HF-HClO4消解体系消解飞灰样品,通过选择合适的待测同位素以及干扰元素校正方程校正质谱干扰,建立了全自动消解-电感耦合等离子质谱(ICP-MS)法测定飞灰样品中铍、钒、铬、锰、镍、铜、锌、镉、铅等9种元素的新方法。采用嵌片技术和碰撞模式消除基体干扰,采用单一内标~(103) Rh进行信号漂移校正,9种元素校准曲线的线性相关系数均大于0.999,方法检出限在0.01～0.3μg/g。用飞灰标准物质SRM1633C进行验证,平均相对标准偏差RSD在0.54%～2.4%,加标回收率为85%～120%,各元素的测定值与标准值吻合。方法具有较好的准确度和精密度,适合垃圾焚烧产生飞灰样品中全量金属的测定。     

全自动消解电感耦合等离子体质谱仪测定环境土壤中铍钡铊银

采用HNO3-HF-HCl O_4消解体系,利用全自动消解仪优化的程序消解土样,电感耦合等离子体质谱仪(ICP-MS)碰撞气流速3.0~4.0 mL/min,以7Li,~(103)Rh,~(209)Bi作为内标,通过编辑干扰元素校正方程校正质谱干扰,建立全自动消解电感耦合等离子体质谱仪测定土壤中铍、钡、铊、银4种元素的新方法。结果表明:铍、钡、铊、银校准曲线r0.999,方法检出限在0.005~0.1μg/g之间,RSD为0.19%~2.0%,加标回收率在100.0%~109.2%,该方法用GSS-13和GSS-10标准样品验证,相对误差-3.8%~1.7%,与标准值吻合。采用实验方法对松花江河岸土壤中4种元素进行测定,并用电感耦合等离子体发射光谱法(ICP-AES)进行仪器比对,结果基本一致。     

微波消解-电感耦合等离子体光谱仪测定环境土壤中镧铈铷锶四种元素的研究

基于HNO3-HF-HCl酸消解体系,建立微波消解-电感耦合等离子体发射光谱仪测定环境土壤中镧铈铷锶四种元素的方法。利用恒定的氩气流作内标校正土壤基体干扰,采用径向观测模式,利用多重谱线拟合技术(MSF)校正光谱干扰,提升本方法的检出限和精密度。结果表明：该方法校准曲线r>0.999,检出限在1.5~7.0 μg/g,RSD在0.9%~5.7%之间,加标回收率83.0%~117%,该方法用GSS-8、GSS-13标准样品验证,效果良好。     

分类消解-电感耦合等离子体原子发射光谱法测定环境土壤中15种金属元素的含量

测定土壤中铍、锌、钼、铊、钛、锑等6种元素以硝酸-氢氟酸-高氯酸混合酸为消解体系,采用全自动消解法进行消解;测定土壤中钒、锰、钴、镍、铜、镉、钡、铅、铬等9种元素以硝酸-氢氟酸-盐酸混合酸为消解体系,采用微波消解法进行消解。以氩为内标元素校正土壤基体的雾化效率及电离效率。电感耦合等离子体原子发射光谱法(ICP-AES)采用多向观测模式,结合多重谱线拟合技术(MSF)校正光谱干扰,测定环境土壤中上述15种元素的含量,检出限为0.1~3.7 mg·kg~(-1)。按上述方法测定标准样品GSS~(-1)0和GSS~(-1)3,各元素的测定值与认定值吻合,相对标准偏差(n=11)为0.15%~2.6%。以吉林市某河岸土壤为实际测定样品,各元素的测定值与电感耦合等离子体质谱法(ICP-MS)的测定值一致,相对标准偏差(n=11)为1.6%~4.5%。     

电感耦合等离子体质谱法测定可食性油墨中的13种化学元素

采用微波消解-电感耦合等离子体质谱法测定可食性油墨中的铬、砷、硒、镍、铁、锰、铜、铅、镉、锑、锌、钡和铝等13种化学元素。以硝酸-过氧化氢(3+2)混合液为消解剂对样品进行微波消解,以铋、锗、钪和铟作为内标消除基体干扰,采用碰撞/反应池技术和干扰校正公式消除质谱干扰。各元素的质量浓度在一定范围内与其对应的信号强度呈线性关系,相关系数在0.999 1~0.999 9之间,方法的检出限(3s/k)在0.003~2mg·kg~(-1)之间。加标回收率在80.0%~110%之间,测定结果的相对标准偏差(n=7)在2.3%~7.3%之间。     

电感耦合等离子体质谱法同时测定葡萄中40种痕量元素

葡萄样品用微波消解处理后,采用电感耦合等离子体质谱法测定所得样品溶液中40种元素的含量。使用合适的同位素、内标和干扰校正方程消除了被测元素的干扰。方法的检出限(3s)在0.003 6～0.53μg·L-1之间。方法用于苹果标准物质(GBW 10019)的分析,测定值与认定值相符,相对标准偏差(n=6)在1.6%～8.5%之间。     

ICP-MS法测定菊花茶中砷镉铜铅锌

采用电感耦合等离子体质谱(ICP-MS)法,对菊花茶中微量元素砷、铅、镉、铜、锌进行了分析。用HNO3-H2O2消解样品,通过在线加入内标校正基体效应和接口效应,通过修正方程校正质量数干扰。测定元素校正曲线的相关系数都在0.999 5以上,各元素的检出限在0.020~0.14μg.L-1,样品分析结果的相对标准偏差为1.5%~4.3%(n=10),加标回收率在93.9%~101.6%之间。用此方法测定茶叶标准物质GBW 07605,结果与标准值基本一致。     

电感耦合等离子体质谱法测定高纯铝中杂质元素

高纯铝样品经盐酸(1+1)溶液微波消解,采用电感耦合等离子体质谱法测定所得样品溶液中钛、铁、铜、锌、镓、银、镉、铟和铅等杂质元素的含量。选择适当的待测元素的同位素克服了质谱干扰,定量加入50μg·L~(-1)铯和锗内标元素有效地校正了基体效应。选用碰撞室技术消除了多原子离子对部分被测元素的干扰。结果表明:方法的检出限(3s)在0.003～0.042μg·L~(-1)之间。高纯铝样品中9种元素测定结果的相对标准偏差(n=10)在2.9%～9.5%之间。方法用于精铝标准样品(R11C)的测定,结果与认定值基本相符。     

电感耦合等离子体质谱(ICP-MS)法测定金绿宝石中16种痕量稀土元素

金绿宝石结构稳定,常规敞开酸溶、密闭酸溶、微波消解三种前处理方法并不能将其完全分解,测定结果偏低。本文采用碳酸钠-硼酸混合熔剂进行熔融,样品分解完全,建立了电感耦合等离子体质谱法(ICP-MS)测定金绿宝石中16种痕量稀土元素的分析方法。选择丰度高、干扰小的同位素、动能歧视碰撞池(KED)模式及干扰系数校正法消除质谱干扰,以185Re为内标元素及样品稀释降低基体干扰。实验表明：各稀土元素的校准曲线相关系数r值在0.9991~0.9998之间,方法检出限为0.0001~0.0134 μg/g,定量限为0.0005~0.0670 μg/g。采用国家标准物质GBW07151验证方法的精密度,计算出相对标准偏差(RSD, n=7)在1.3%~4.6%之间,并将此方法用于金绿宝石实际样品中稀土元素的测定,RSD为0.9%~3.2%,加标回收率为94%~104%,符合国家地质矿产行业标准,结果稳定、可靠。     

微波消解-电感耦合等离体子质谱法(ICP-MS)同时测定畜禽粪便中7种重金属元素

粪便样品干燥、研磨后,称取0.25 g样品,加入8 mL硝酸,采用微波消解方法进行前处理。采用KED模式消除质谱干扰,采用内标校正消除非质谱干扰(Ge作为Cu、Zn、Cr的内标,Bi作为Hg和Pb的内标,Rh作为As和Cd的内标),建立了可同时测定畜禽粪便中Cu、Zn、Cr、As、Cd、Pb、Hg 7种重金属元素的微波消解-电感耦合等离子体质谱法。方法线性相关系数均在0.9995以上,检出限为0.005~0.305μg/L,加标回收率为83.6%~112%,相对标准偏差为0.70%~5.6%。方法灵敏度、准确度和精密度高,实用性强,适用于同时检测畜禽粪便中多种重金属元素,对畜禽粪便的科学还田具有指导意义。     

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。     

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.     

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.     

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.     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

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^-。     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.