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1.
胡斌  江祖成 《分析化学》1993,21(10):1139-1143
本文系统研究了氟化电热蒸发/电感耦合等离子体原子发射光谱(ETV-ICP-AES)测定难熔元素的基体效应。与常规气动雾化(PN)-ICP-AES中的基体效应比较,氟化ETV-ICP-AES中的基体效应更小。对难熔基体元素,由于基体和待测元素与氟化剂之间的竞争反应,随着基体浓度的增加,待测元素谱线强度降低;对常见基体元素,由于热循环中基体与待测元素之间的选择挥发,对待测元素的蒸发和传输过程无明显影响  相似文献   

2.
胡斌  江祖成 《分析化学》1996,24(4):377-381
本文探讨了电热蒸发-电感耦合等离子体原子发射光谱法(ETV-ICP-AES)测定不同挥发性元素Ti、Ni和Pb时含氟基体改进剂的改进作用。发现聚四氟乙烯(PTFE)是所试验的含氟试剂是最理想的基体改进剂。与无基体改进剂的情形相比,采用PTFE作基体改进剂可使难烷元素Ti和中等挥发元素Ni的检出了奶分别改善350和8倍,但对易挥发元素Pb则无明显的影响。这表明,以PTFE为基体改进剂ETV-ICP-  相似文献   

3.
1 引  言随着国内半导体工业的蓬勃发展 ,半导体材料及器件中的分析技术也显得越来越重要。在半导体制造过程中 ,硼磷硅玻璃 (BPSG)作为硅片表面的平整介质和钝化层 ,其中B、P的含量直接影响它的性能。B、P分析方法有多种 ,如美国Balazs公司采用的是等离子体发射光谱法 (ICP OES)。本文用等离子体质谱法 (ICP MS)对B、P进行检测 ,与Balazs的分析结果对照 ,效果良好 ,而且与ICP OES相比 ,B、P的检出限降低了 1~ 2个数量级 ,有很高的实用价值。2 实验部分2 1 仪器及试剂 VGPQ3等离子体…  相似文献   

4.
复合固体超强酸SO_4~(2-)/TiO_2-Fe_2O_3催化合成丁酸异丁酯   总被引:3,自引:0,他引:3  
采用溶胶 凝胶法制备的复合固体超强酸催化剂SO2-果表明物质的量比n(Ti)∶n(Fe)=2∶1时催化剂活性最高,这与文献结果[2]有所不同。1 实验部分1 1 试剂和仪器丁酸、异丁醇、苯、表面活性剂(PEG-600)、乙醇、三氯化铁等为分析纯;钛酸四丁酯为化学纯。上海产WZS-1型阿贝折射仪;日本岛津GC-16A气相色谱仪;GEMINI2360型氮气吸附全自动表面分析仪。1 2 催化剂SO2-4/TiO2-Fe2O3的制备、酸强度及BET表面积测定  取一定量的钛酸四丁酯剧烈搅拌下缓慢滴加到80ml无水乙醇中,搅拌20min,快速加入80ml2…  相似文献   

5.
有机溶剂对ICP—AES分析性能影响的研究   总被引:3,自引:0,他引:3  
研究了有机溶剂对电感耦合等离子体-原子发射光谱(ICP-AES)分析性能的影响。MonteCarol模拟结果和实验结果表明,只要选择合适的操作参数,有机溶剂直接引入ICP不仅不会影响ICP的稳定性,还会提高某些元素的灵敏度,从而提高了ICP-AES的分析性能。  相似文献   

6.
虞磊  吕宝源 《分析化学》2000,28(1):42-45
对电感耦合等离子体原子发射光谱(ICP-AES)法测定高纯三甲基镓(99.9999T,相对于金属镓的含量)中Cu、Fe、Si、Zn等31种痕量杂质元素的含量进行了研究,考察了基体元素镓对杂质元素的光谱和非光谱干扰以及基体浓度对杂质元素谱线信噪比和检出限的影响在优化的实验条件下,获得了满意的结果。  相似文献   

7.
采用ICP AES法同时测定新疆大宗进口商品普碳钢中硅、锰和磷。通过对ICP操作条件的选择 ,三种元素测定谱线的校准和确定 ,基体匹配法消除铁基体对被测元素光谱线的光谱干扰 ,选择标样进行测定 ,结果满意 ,方法适用于大批量普碳钢的元素测定 ,简单、快速、准确。1 试验部分1.1 仪器与工作条件ICP IRIS全谱直读等离子光谱仪 (美国热电公司 )功率 115 0W ,积分时间高波 10s ,低波 5s,样品冲洗时间 30s ,冲洗泵速 10 0r·min- 1,分析泵速 10 0r·min- 1(1.85ml·min- 1) ,延迟时间 0s ,雾化气压力2 10kP…  相似文献   

8.
ICP-AES中基体元素对硫的光谱干扰(Ⅱ)卢汉兵张保军,魏路线(武汉华中师范大学分析测试中心,武汉,430070)(武汉工学院微观分析中心)关键词电感耦合等离子体发射光谱,光谱干扰,硫ICP-AES中,由于对200nm以下的光谱干扰研究工作报道极少...  相似文献   

9.
于爱民  刘晓晶 《分析化学》1993,21(11):1320-1322
本文提出一种测定贵金属元素的微波等离子体炬原子发射光谱法(MPTAES)。采用自制的超声雾化微量进样装置进样,以氩气为工作气体,探讨了观察高度,微波功率,体系介质,氩气流量和共存元素对被测元素发射信号的影响。选用合适的分析线和MPT光源的工作参数,其方法的检出限分别为5.8(Au),0.5(Ag)12(Pt),1.6(Rh)和t1.0ng/ml(Pd)。实际样品中金和银的测定结果是令人满意的。  相似文献   

10.
ICP—AES法测定镍基合金中合金元素含量   总被引:3,自引:0,他引:3  
ICP AES法灵敏度高 ,线性范围宽 ,并同时测定多种元素 ,已成为现代分析测试技术中一个重要的检测手段 ,广泛地应用在各个领域。由于核电用材镍基合金焊丝及焊带是以镍作为基体 ,硅、锰、铬、铁等元素含量较高 ,而钛、铝的含量却很低 ,其基体较复杂 ,各元素含量相差又较悬殊 ,所以给分析工作带来困难。本文采用PS 6型ICP多道真空光谱仪 ,通过对镍基合金试样的溶解方法、等离子体发射光谱仪的工作参数、共存元素的干扰、离峰分析校正等进行了研究 ,从而制定了相应准确有效的方法 ,解决了生产检测的困难 ,结果满意[1] 。1 试验部分…  相似文献   

11.
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.  相似文献   

12.
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。  相似文献   

13.

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.

  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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, Mo, 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 600-700oC. 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.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
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^-。  相似文献   

18.
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.  相似文献   

19.
20.
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。  相似文献   

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