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Journal of Materials Science and Chemical Engineering 2020年第10期8卷 11-20页

作者： Vasiliy A. Tyumentsev Alfiya G. Fazlitdinova Condensed Matter Physics Department Physics Faculty Chelyabinsk State University Chelyabinsk Russia

The properties of synthetic graphite materials, widely used in advanced fields, are determined by their structure, which is formed in the process of high-temperature (~2500°C) heat treatment. The fine structure of a graphitizing carbon material based on petroleum coke containing 1.3 wt% S at various stages of graphitization was studied by x-ray diffraction analysis. Some of the samples contained the addition of dispersed Fe2O3. It is shown that the heat-treated material in the range 1200°C - 2600°C is heterogeneous, its component composition is determined by the processing temperature and the presence of Fe2O3 additive. The observed dependence of the component composition on the heat treatment temperature suggests that the process of graphitization of the carbon material, apparently, develops through a number of metastable states.

关键词： Graphitization x-ray diffraction analysis Microstructure Coherent Scattering Regions

Microstructure and optical absorption properties of Au/NiO thin films

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 115-120页

作者： Cui-hua Zhao Bo-ping Zhang Shi-jing Wang Peng-peng Shang Can Chen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China College of Materials Science and Engineering Guangxi University Nanning 530004 China

Au nanoparticles dispersed NiO composite films were prepared by a chemical solution method. The phase structure, microstructure, surface chemical state, and optical absorption properties of the films were characterized by x-ray diffraction, transmission electron microscopy, x-ray photoelectron spectroscopy, and Uv-vis spectrometer. The results indicate that Au particles with the average diameters of 35–42 nm are approximately spherical and disperse in the NiO matrix. The optical absorption peaks due to the surface plasmon resonance of Au particles shift to the shorter wavelength and intensify with the increase of Au content. The bandwidth narrows when the Au content increases from 8.4wt% to 45.2wt%, but widens by further increasing the Au content from 45.2wt% to 60.5wt%. The band gap E g increases with the increase of Au contents from 8.4wt% to 45.2wt%, but decreases by further increasing the Au content.

关键词： thin films nanostructured materials solutions synthesis x-ray diffraction analysis optical properties microstructure

Isolation and Crystal Structure of 1',4'-Trans-diol of Abscisic Acid

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1085-1089页

作者： WANG Tian-Shan ZHOU Jin-Yan TAN Hong Chengdu Institute of Biology The Chinese Academy of Sciences Chengdu 610041 China Department of Chemistry Hainan Normal University Haikou 571158 China

1 ′,4′-Trans-diol of abscisic acid was isolated from botrytis cinerea as a colorless crystal. The molecular and crystal structures have been determined by x-ray diffraction analysis. It crystallizes in orthorhombic system, space group P212121 with a = 6.724（3）, b = 17.559（6）, c = 12.265（2）,A,α =β=γ= 90°, V= 1448.1（8）,A^3, Z=4, Dx = 1.222 g/cm^3, F（000） = 576 and μ（MoKa） = 0.087 mm^-1. The final R = 0.0628 and wR = 0.1604 for 2501 independent reflections with Rint - 0.0160 and 1679 observed reflections with 1 〉2σ（I）. There are three intermolecular hydrogen bonds in a unit cell.

关键词： botrytis cinerea abscisic acid 1′,4′-trans-diol of abscisic acid x-ray diffraction analysis

Theoretical and Experimental Study of the Reaction of 2-Guanidinobenzimidazole on a Series of meta-Substituted Benzaldehydes

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Chemical Research in Chinese Universities 2017年第5期33卷 765-772页

作者： MONIA Chebbi HAMMOUDA Chebbi HEDI M'rabet YOUS SEF Arfaoui Unit of Physical Chemistry of Condensed Materials Laboratory of Materials Crystallochemistry and Applied Thermodynamic Laboratory of Organic and Heterocyclic Synthesis Department of Chemistry Faculty of Sciences University of Tunis EI-Manar 2092 Tunisia

The syntheses of a variety of 1,3,5-triazinebenzimidazoles obtained by the cyclocondensafion reaction of 2-guanidinobenzimidazole with a series of meta-substituted benzaldehydes were reported. The prepared compounds were fully characterized by IR and NMR spectroscopies. Based on the density functional theory（DFT） calculations method, quantum chemical calculations were performed by Gaussian 09 set of programs. All possible transition states, reactants and products were fully optimized at the hybrid density functional B3LYP level using the 6-311＋G（d,p）. The geometries of five possible tautomers of 2-amino-4-aryl[1,3,5]triazino[1,2-a]benzimidazoles were optimized in ethanol, using conductor like polarizable confinuum（CPCM） in the gas phase. The energetic diagrams of tautomeric equilibrium showed that form A is the most stable tautomer which proved to be in accordance with the x-ray diffraction structure analysis. In order to interpret the reaction mechanism, the chemical reactivity was studied using local and global reactivity indexes.

关键词： 2-Amino-4-aryltriazino[1,2-a]benzimidazole 2-Guanidinobenzimidazole Density functional theory Tautomeric equilibrium Reaction mechanism x-ray diffraction analysis

Phase diagram of the CsBr-CaBr_2 system

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Rare Metals 2006年第3期25卷 293-296页

作者： BAO xinhua CHEN Nianyi LU Wencong CHENG Zhixuan LUO Yunyun LU Weiying xIA Yiben School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Sciences Shanghai University Shanghai 200444 China

The phase diagram of the CsBr-CaBr2 system was re-determined by using differential thermal analysis and high ternperature and room ternperature x-ray diffraction analysis. It is concluded that there are three intermediate compounds in this system： *** melting compound, CsCaBr3, with a melting point of 823℃ and two incongruently melting compounds, Cs2CaBr4 and Cs3Ca2Br7, whose peritectic points being 597℃ and 635℃, respectively. x-ray diffraction analysis indicated that compound CsCaBr3 is of slightly distorted perovskite structure.

关键词： phase diagram CsBr-CaBr2 system differential thermal analysis (DTA) x-ray diffraction analysis perovskite structure

Isolation and Crystal Structure of Trans-2,2',4,4'-tetramethyl-6,6'-dinitro Azobenzene

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Chinese Journal of Structural Chemistry 2004年第9期23卷 1005-1008页

作者： WANG xiao-Ling YANG Bo-Lun LI Zong-xiao YUAN Chun-Lan YU Kai-Bei Environmental and Chemical Engineering Institute Xian Jiaotong UniversityXi'an 710049China Department of Chemistry and Chemical Engineering Baoji College of Arts and SciencesBaoji 721007China Chengdu Institute of Organic Chemistry The Chinese Academy of SciencesChengdu 610041China

Trans-2,2?,4,4?-tetramethyl-6,6?-dinitro azobenzene (C16H16N4O4, Mr = 328.32) was isolated from benzene extract of the leaves of Aconitum sungpanense Hand. Mazz. as a new compound, and characterized by spectral methods and x-ray diffraction analysis. It crystallizes in monoclinic system, space group P21/c with a = 8.544(1), b = 13.997(2), c = 7.161(1) ? ?= 112.97(1), V = 788.4(2) ?, Z = 4, Dc = 1.383 g/cm3, F(000) = 344 and ?MoKa) = 0.102 mm-1. The final R = 0.0395 and wR = 0.1140 for 1913 independent reflections with Rint = 0.0109 and 1329 observed reflections with I > 2s(I). The molecule is composed of two phenyl rings through trans N=N.

关键词： trans-2,2′,4,4′-tetramethyl-6,6′-dinitro azobenzene aconitum sungpanense Hand.Mazz. spectral methods x-ray diffraction analysis

Crystal Structure of 8-Demethoxyrunanine

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Chinese Journal of Structural Chemistry 2008年第10期27卷 1250-1254页

作者：王晓玲 Department of Chemistry and Chemical Engineering Baoji University of Arts and Sciences

A new hasubanane-type alkaloid, 8-demethoxyrunanine, was isolated from Sino- menium acutum and characterized by melting point, HREIMS, 1H NMR, and x-ray diffraction analysis. x-ray diffraction reveals that the title compound crystallizes in the orthorhombic system, space group P212121 with a = 7.308（1）, b = 21.742（5）, c = 22.893（4）A, V = 3637.5（11） A^3, Z = 8, Dx = 1.254 g/cm^3, F（000） = 1472, μ（MoKα） = 0.087 mm^-1, the final R = 0.0438 and wR = 0.0575 for 4497 independent reflections with Rint = 0.0192 and 2091 observed reflections with I 〉 2σ（I）. Four rings （ring A： one benzene ring, ring B： one hexagon carbon ring in a half-chair conformation, ring C： one hexagon carbon ring with α,β-unsaturated ketone segment （-CR2=CR1-C=O） in a screw-boat conformation, and ring D： one nonplanar tetrahydropyrrole） form a hasubanane-type alkaloid.

关键词： Sinomenium acutum 8-dernethoxyrunanine crystal structure x-ray diffraction analysis

Effect of Calcium Leaching on the Properties of Cement-based Composites

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Journal of Wuhan University of Technology(Materials Science) 2011年第5期26卷 990-997页

作者：林威廷鄭安 Institute of Nuclear Energy Research Atomic Energy Council Dept.of Civil Engineering National Ilan University

Leaching is one of the major factors that alter the mechanical properties of cement-based *** study is aimed to investigate the effect of leaching on the properties of cement-based *** with two water/cementitious ratios and two mineral admixtures were *** electrical potential was applied to accelerate the leaching *** strength test,scanning electronic microscopy,thermogravimetric analysis and x-ray diffraction analysis were *** results demonstrated that the calcium leaching reduced compressive strengths of concrete specimens,and such effect was prominent on the specimens without mineral *** leaching resistance increased with a decrease in water/cementitious ratio and an increase in amount of mineral *** mineral admixtures would reduce the amount of calcium hydroxide and refine the pore structure through pozzolanic reactions.A fair relationship was found between the calcium leaching and the compressive strength.

关键词： leaching slag silica fume x-ray diffraction analysis thermo gravimetric analysis

Two Labdane Diterpenes from Leonurus heterophyllus

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Chinese Chemical Letters 2006年第10期17卷 1321-1324页

作者： xian ZHANG Guo Ping PENG School of Pharmacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 Botanical Refinement Engineering Research Center Nanjing University-of Traditional Chinese Medicine Nanjing 210029

Two new labdane diterpenoids named heteronone A （1） and heteronone B （2） were isolated from the aerial parts of Leonurus heterophyllus Sweet. Their structures were established by various spectroscopic means, and t... 详细信息

关键词： Labdane diterpenes leonurus heterophyllus Sweet. x-ray diffraction analysis

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan University of Technology(Materials Science) 2008年第6期23卷 901-906页

作者：莫祥银 analysis and Testing Center & Jiangsu Key Laboratory of Biofunctional Materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of China, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with x-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy