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排序方式: 共有567条查询结果,搜索用时 15 毫秒
1.
Ajeel Raheem K. Salim W. S.-I. W. 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1161-1173
Journal of Thermal Analysis and Calorimetry - Over the last few decades, tremendous consideration is drawn towards corrugation surfaces because of their advantages over the improvement in thermal... 相似文献
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3.
Mousa Z. Al-Noaimi Raid J. Abdel-Jalil Mustafa M. El-Abadelah Salim F. Haddad Younis N. H. Baqi Wolfgang Voelter 《Monatshefte für Chemie / Chemical Monthly》2006,37(12):745-750
In the presence of RuCl3, N-phenylamidrazone underwent oxidative cyclization into 1,4-dihydro-1-phenyl-1,2,4-benzotriazine, the structure of which is
established by spectral and X-ray diffraction data. 相似文献
4.
Derrouiche S Gravejat P Bianchi D 《Journal of the American Chemical Society》2004,126(40):13010-13015
The heats of adsorption of two linear CO species adsorbed on the Au degrees particles (denoted L(Au degrees)) and on the Ti(+delta) sites (denoted L(Ti+delta)) of a 1% Au/TiO(2) catalyst are determined as the function of their respective coverage by using the AEIR procedure (adsorption equilibrium infrared spectroscopy) previously developed. Mainly, the evolutions of the IR band area of each adsorbed species (2184 cm(-1) for L(Ti+delta) and at 2110 cm(-1) for L(Au degrees)) as a function of the adsorption temperature T(a), at a constant CO adsorption pressure P(CO), provide the evolutions of the coverages theta(LTi+delta) and theta(LAu degrees ) of each adsorbed CO species with T(a) in isobar conditions that give the individual heats of adsorption. It is shown that they linearly vary from 74 to 47 kJ/mol for L(Au degrees ) and from 50 to 40 kJ/mol for L(Ti+delta) at coverages 0 and 1, respectively. These values are consistent with literature data on model Au particles and TiO(2). In particular, it is shown that the mathematical formalism supporting the AEIR procedure can be applied to literature data on Au-containing solids (single crystals and model particles). 相似文献
5.
The complex of cadmium with the reagent 2-(-5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) has been studied. The composition, stability constant, and free energy change of formation of the complex have been determined. A sensitive spectrophotometric method for the determination of cadmium has been developed and applied for a range of concentration of 0.4–4.0 μg/ml cadmium using the complex Cd-5-Br-PADAP. The optimum conditions for maximum sensitivity of determination such as standing time, pH, wavelength, and order of addition have been determined. The effect of foreign ions on this method has been also studied. 相似文献
6.
The preparation of CuI + Ag2S and Cu2[HgI4] + Ag2S membranes hydrophobised by PTFE is described. The pressed membranes mounted in a multi-purpose all-solid-state electrode body have been examined as electrochemical sensors for Cu2+ and I– ions. For the electrode with (CuI + Ag2S + PTFE)-membrane experimental slopes of 29 mV(pCu)–1 and 62 mV(pI)–1 were obtained, in good agreement with the theoretical values. For practical measurement in solutions where both Cu2+ and I– can be present, the investigated electrode offers certain advantages in comparison with a commercial Cu-ISE. 相似文献
7.
The W/Pt bimetallic pair has been applied in various potentiometric titrations. Except for the neutralization of dicarboxylic acids, e.g., oxalic, the pair is suitable for neutralization titrations where ΔE/ΔV values at the equivalence point are higher on W than on Pt. Tungsten oxides increase the inflexion pd. The pair is also suitable for oxidation/reduction titrations using permanganate, dichromate, and ceric sulfate, and for precipitation reactions with silver nitrate. However, it gives a small inflexion pd in the oxidation of thiosulfate by iodine. EDTA titrations of copper, magnesium, and calcium give a sharp inflexion in the case of copper only. This pair may be useful in routine analyses requiring a robust electrode assembly but not a high degree of accuracy. 相似文献
8.
G. Bigazzi S. Meloni M. Oddone G. Radi 《Journal of Radioanalytical and Nuclear Chemistry》1986,98(2):353-363
Iron and trace elements, such as rare-earth elements, scandium, rubidium, cesium, tantalum, thorium and uranium were determined by instrumental neutron activation analysis in geological samples of obsidian rocks from the Mediterranean Area and in obsidian artifacts found in some prehistorical human settlements in Italy. REE patterns and discriminant analysis allow a firm identification of the source material of artifacts, thus confirming and implementing fission track data of the same artifacts and rocks on the origin of the obsidian rock used to mould the artifacts. 相似文献
9.
The complexes of the reagent 5-Br-PADAP with the metal ions La(III), Ce(III), and Y(III) have been studied.The composition and stability of these complexes have been determined. A sensitive spectrophotometric procedure for the determination of the metal ions La(III), Ce(III), and Y(III) has been proposed. The limitations of this procedure and the effect of other ions have been studied. 相似文献
10.
The adsorptive behavior of the anti-inflammatory drug meloxicam was studied by cyclic, differentia-pulse and square-wave voltammetry on a hanging mercury drop electrode (HMDE). The drug was accumulated at HMDE and a well-defined stripping peak current was obtained at -1.42 V vs. Ag/AgCl (saturated KCl) electrode in acetate buffer solution (pH 5.0). A voltammetric procedure was developed for the determination of meloxicam using square-wave cathodic adsorptive stripping voltammetry (SW-CASV). The optimum working conditions for the determination of the drug were established. The analysis of meloxicam in human plasma was carried out satisfactorily. 相似文献