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1.
综述了地质样品中总锡分析方法(包括容量法、分光光度法、氢化物发生-原子荧光光谱法、原子吸收光谱法、极谱法、原子发射光谱法、电感耦合等离子体原子发射光谱法、电感耦合等离子体质谱法、X射线荧光光谱法)的研究进展。  相似文献   

2.
综述了铁矿石中砷含量的测定方法研究进展,主要包括分光光度法、原子吸收光谱法、原子荧光光谱法、电感耦合等离子体-原子发射光谱法、电感耦合等离子体质谱法和X射线荧光光谱法等(引用文献45篇)。  相似文献   

3.
食品中铝检测方法研究进展   总被引:1,自引:0,他引:1  
介绍了食品中铝的来源,并综述了近十年中食品中铝测定方法的研究进展,包括电感耦合等离子体原子发射光谱法、电感耦合等离子体质谱法、石墨炉原子吸收光谱法、电化学分析法以及分光光度法等方法(引用文献75篇)。  相似文献   

4.
本文综述了近年来国内食品中镉的检测技术,包括火焰原子吸收光谱法、石墨炉原子吸收光谱法、原子荧光光谱法、分光光度法、阳极溶出伏安法、电感耦合等离子体质谱法和电感耦合等离子体原子发射光谱法等传统检测技术,以及生物化学传感器法、免疫分析法、酶分析法和试纸法等快速检测技术(引用文献42篇)。  相似文献   

5.
介绍了炭素材料中微量元素的测定方法,内容包括国际标准、国外先进标准、中国国家标准和行业标准。测定方法涵盖了重量法、分光光度法、原子吸收光谱法、电感耦合等离子体原子发射光谱(ICP-AES)、电感耦合等离子体质谱法(ICP-MS)、X射线荧光光谱分析法(XRF)等。并阐述了铝用炭素中微量元素测定标准样品的研制。  相似文献   

6.
对2000~2008年间有关锗分析方法的研究进展作了综述。内容包括滴定法、分光光度法、荧光光谱法、原子荧光光谱法、原子吸收光谱法、电感耦合等离子体原子发射光谱法、电感耦合等离子体质谱法和电化学法等,指出了各分析方法的特点和不足,展望了这些分析方法在锗分析中的应用前景(引用文献65篇)。  相似文献   

7.
钴的检测方法进展   总被引:2,自引:0,他引:2  
综述了自1988至2005年间国内外钴的检测方法,包括分光光度法、原子吸收光谱法、极谱法、高效液相色谱法、化学发光法、电感耦合等离子体发射光谱法、电感耦合等离子体质谱法等。  相似文献   

8.
评述了2007年10月至2009年12月期间国内在金属材料分析领域的现状及进展概况.内容包括重量分析法、滴定分析法、分光光度法和荧光光度法、催化动力学光度法、原子吸收光谱法和原子荧光光谱法、电感耦合等离子体原子发射光谱法和电感耦合等离子体质谱法、光电直读光谱法、X射线荧光光谱法、原位统计分析及电化学方法等其他分析方法、...  相似文献   

9.
正地质样品中银的测定方法主要有分光光度法、原子发射光谱法~([1])、石墨炉原子吸收光谱法(GFAAS)~([2])、火焰原子吸收光谱法(FAAS)~([3])、电感耦合等离子体原子发射光谱法(ICP-AES)~([4])及电感耦合等离子体质谱法(ICP-MS)等。目前。较为常用的分析方法为原子发射光谱法、GFAAS及ICPAES,这3种方法因存在分析流程长、灵敏度低和线性范围窄等缺点,已无法满足地质工作日益发展的需求。而ICP-MS作为近几年出现的新型分析方  相似文献   

10.
流动注射分析法与多种仪器分析联用的进展   总被引:3,自引:0,他引:3  
对流动注射分析法(FIA)与多种仪器分析方法,包括分光光度法、电感耦合等离子体原子发射光谱法(ICP-AES)、原子吸收光谱法(AAS)、化学发光法(CL)、荧光光度法、电化学分析法、生物传感器、毛细管电泳、免疫分析法等联用在最近两年中的新进展作了评述,引述文献42篇.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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.  相似文献   

16.
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 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.  相似文献   

19.
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.  相似文献   

20.

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   

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