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油浸法快速校正X射线衍射矿物定量分析
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作者 杨艳芳 《矿产保护与利用》 2001年第4期24-26,共3页
将油浸法应用到海泡石、刚玉等矿物岩石的X射线衍射矿物定量分析中 ,使其相互取长补短 ,相得益彰。实践证明 ,两者的结合是一种快捷、准确的矿物定量方法。
关键词 x线线衍射 油浸法 定量分析 快速校正 海泡石 刚玉
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Extraction of nickel from molybdenum leaching residue of metalliferous black shale by segregation roasting and acid leaching 被引量:4
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作者 楚广 赵思佳 杨天足 《Journal of Central South University》 SCIE EI CAS 2012年第2期340-346,共7页
The recovery of nickel from molybdenum leach residue by the process of segregation roasting-sulfuric acid leaching-solvent extraction was investigated. The residue was characterized by microscopic investigations, usin... The recovery of nickel from molybdenum leach residue by the process of segregation roasting-sulfuric acid leaching-solvent extraction was investigated. The residue was characterized by microscopic investigations, using X-ray fluorescence spectrometry (XRF) and X-ray diffractometry (XRD) techniques and the residue after segregation roasting was characterized by chemical phase analysis method. A series of experiments were conducted to examine the mass ratio of activated carbon (AC) to the residue, segregation roasting time and temperature, sulfuric acid concentration, liquid-to-solid ratio, leaching time, leaching temperature, addition amount of 30% H2O2, stirring speed (a constant) on the leaching efficiency of nickel. A maximum nickel leaching efficiency of 90.5% is achieved with the mass ratio of AC to the residue of 1:2.5, segregation roasting time of 2 h, segregation roasting temperature of 850 ℃, sulfuric acid concentration of 4.5 mol/L, liquid-to-solid ratio of 6:1, leaching time of 5 h, leaching temperature of 80 ℃, addition of 30% H202 of 0.6 mL for 1 g dry residue. Under these optimized conditions, the average leaching efficiency of nickel is 89.3%. The nickel extraction efficiency in the examined conditions is about 99.6%, and the nickel stripping efficiency in the examined conditions is about 99.2%. 展开更多
关键词 metalliferous black shale segregation roasting nickel leaching PC-88A solvent extraction
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Investigation of Temperature Dependency of Morphological Properties of Thermoplastic Polyurethane using WAXS and SAXS Monitoring 被引量:1
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作者 Steffen Thomas Witzleben Katharina Walbrueck +1 位作者 Stephanie Elisabeth Klein Margit Schulze 《Journal of Chemistry and Chemical Engineering》 2015年第8期494-499,共6页
Polyether and polyether/ester based TPU (thermoplastic polyurethanes) were investigated with wide-angle XRD (X-ray diffraction) and SAXS (small angle X-ray scattering). Furthermore, SAXS measurements were perfor... Polyether and polyether/ester based TPU (thermoplastic polyurethanes) were investigated with wide-angle XRD (X-ray diffraction) and SAXS (small angle X-ray scattering). Furthermore, SAXS measurements were performed in the temperature range of 30 ℃ to 130 ℃. Polyether based polymers exhibit only one broad diffraction signal in a region of 2 θ 15° to 25°. In case of polyurethanes with ether/ester modification, the broad diffraction signal arises with small sharp diffraction signals. SAXS measurements of polymers reveal the size and shape of the crystalline zones of the polymer. Between 30 ℃ and 130 ℃ the size of the crystalline zone changes significantly. The size decreases in most of investigated TPU. In the case of Desmopan 9365D an increase of the particle size was observed. 展开更多
关键词 Thermoplastic polyurethanes MORPHOLOGY mechanical properties SAxS WAxS temperature influence CRYSTALLINITY
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Simulation of X-ray Diffraction Line Broadening Caused by Stress Gradients and Determination of Stress Distribution by Fourier Analysis
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作者 Vladimir Ivanovltch Monin Joaquim Teixera de Assis Susana Marrero Iglesias 《Journal of Chemistry and Chemical Engineering》 2012年第9期838-842,共5页
Different physical, mechanical and chemical processes, such as: ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gra... Different physical, mechanical and chemical processes, such as: ion implantation, oxidation, nitridation and others create on the surface of materials residual stress state, characterized by high level and strong gradient. X-ray diffraction method widely used for stress measurements has some difficulties in interpretation of experimental data, when the depth of X-ray penetration is compared with thickness of surface layer where inhomogeneous stress distribution is localized. Early it has been shown by authors that diffraction line broadening occurs when analyzed surface is characterized by strong gradient. The interest to study the diffraction line broadening is connected to the possibility of obtaining information about parameters of surface stress distribution. In the present paper the convolution and deconvolution concepts of Fourier analysis were applied to study X ray diffraction line broadening caused by surface stress gradients. Developed methodology allows determining of stress distribution in superficial layers of materials. 展开更多
关键词 Stress gradient x-ray diffraction computer simulation Fourier analysis.
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Influence of Mineral Admixtures on Essential Properties of Ternary Cement Blends
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作者 Eugene Atiemo Charles Kwaku Kankam Francis Momade 《Journal of Civil Engineering and Architecture》 2014年第10期1221-1225,共5页
Two CaCO3-based materials (limestone and clamshells) and steel slag were used as mineral admixtures in cement to produce ternary blends and their influences on hydration and portlandite formation were analyzed. Addi... Two CaCO3-based materials (limestone and clamshells) and steel slag were used as mineral admixtures in cement to produce ternary blends and their influences on hydration and portlandite formation were analyzed. Additionally, mechanical properties were determined. These properties were determined using X-ray diffraction and scanning electron microscopic/energy dispersive X-ray analytical techniques as well as applying methods specified by EN (European Standards) and ASTM (American Standards for Testing and Materials). The portlandite (Ca(OH)E) content was considerably reduced from 36.9% of reference cement to between 13.79% and 15.5%. With the water demand and setting times of the cements containing up to 10%, admixtures did not change significantly. The mechanical tests results showed that ternary blends produced 2-day strengths higher than that specified by EN 197-1 and that blends containing up to 20% admixtures can be used to produce both Class 32.5N and 42.5N cements. 展开更多
关键词 LIMESTONE clamshells steel slag temary cement portlandite compressive strength.
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Structure of the organic crystallite unit in coal as determined by X-ray diffraction 被引量:14
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作者 Song Dangyu Yang Cunbei +2 位作者 Zhang Xiaokui Su Xianbo Zhang Xiaodong 《Mining Science and Technology》 EI CAS 2011年第5期667-671,共5页
X-ray diffraction (XRD) was used to study the structure of the organic crystallite unit (La, Lo doo2) in coals collected from Henan and Shanxi Provinces. XRD patterns of coal were collected in a step-scan mode (0... X-ray diffraction (XRD) was used to study the structure of the organic crystallite unit (La, Lo doo2) in coals collected from Henan and Shanxi Provinces. XRD patterns of coal were collected in a step-scan mode (0.1 °/step) over an angular range of 2-90° (20), allowing 8 s at each step. The structure of the crystallite unit was determined from the Scherrer equation and peak parameters deduced from whole pattern fitting. The results show that the structure of the crystallite unit in coal is mainly controlled by the coal rank. As the coal rank increases the average diameter of a coal crystallite unit (La) increases, the interlayer spacing (doo2) decreases slightly, and the average height of a coal crystallite unit (Lc) increases at first but then decreases. A new diffraction peak from the crystallite unit in coal was found at a low scattering angle in the XRD pattern (2-10~). This suggests a structure with an inter-layer spacing from 1.9 to 2.8 nm exists in coal crystallites. 展开更多
关键词 CoalCrystallitexRDWhole pattern fitting
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Structure-Property Relations in xWO3-0.31P2O5-0.31B2O3-(0.38-x)Cs2O (0.01 ≤ x ≤0.28) Glasses by IR, UV and EPR Spectroscopic Studies
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作者 Bidhu Bhusan Das Ayyacannou Srinivassan Murugesan Yogapriya 《Journal of Chemistry and Chemical Engineering》 2011年第4期369-375,共7页
Glasses in the series of xWO3-0.31P2O5-0.31B2O3-(0.38-x)Cs2O (0.01 ≤ x ≤0.28) (G1-G4: x= 0.01, 0.1, 0.19, 0.28) were prepared by sol-gel method. Glassy phase in the samples were ascertained by powder X-ray d... Glasses in the series of xWO3-0.31P2O5-0.31B2O3-(0.38-x)Cs2O (0.01 ≤ x ≤0.28) (G1-G4: x= 0.01, 0.1, 0.19, 0.28) were prepared by sol-gel method. Glassy phase in the samples were ascertained by powder X-ray diffraction pattern. Differential scanning calorimetry (DSC) traces of the samples show glass transition temperature Tg, in the range 247-253 ℃. IR spectra at 300 K of G1-G4 show the presence of [WO6], [WO4], [PO4]^3-, [PO3]^2-, [BO4]^+, [BO3] units in the glass matrix. Observed electron paramagnetic resonance (EPR) lineshapes show two signals with very different intensities which are associated with W^5+ (5d^1) and Mo^5+ (4d^1) (impurity) paramagnetic sites. Signal with values ofg factors in the range 1.68 〈 g⊥ 〈 1.72 and 1.58 〈 gⅡ 〈 1.62 are due to W^5+ ions present in axially distorted octahedral symmetry. The optical absorption spectra show that the W^5+ ions have pyramidal coordination, involving a tungstyl ion WO^3+ (C4v symmetry). EPR and optical studies suggest the existence of blocks of octahedra linked by tungsten clusters. 展开更多
关键词 Sol-gel method oxide glasses W^5+ ion EPR small polaron optical absorption
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Synthesis and Crystal Structure of a Novel Polymer Copper(Ⅱ) Complex
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作者 王军 卑凤利 +3 位作者 李人宇 杨绪杰 陆路德 汪信 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期665-668,共4页
A novel chain complex was synthesized and its crystal structure has been deter- mined by X-ray diffraction technique. It was found that the local coordination geometry around Cu(Ⅱ) is a distorted tetrahedron and C14H... A novel chain complex was synthesized and its crystal structure has been deter- mined by X-ray diffraction technique. It was found that the local coordination geometry around Cu(Ⅱ) is a distorted tetrahedron and C14H9CuNO3CH3OH is bridged by the carboxylate oxygen atom to form an infinite one-dimensional linear chain. The hydrogen bond exists between O(1) and solvate molecule O(4). The crystal belongs to monoclinic, space group P21 with a = 9.6650(19), b = 7.1280(14), c = 9.925(2) ? b = 98.39(3)? V = 676.4(2) 3, Z = 2, F(000) = 342 and m(MoK? = 1.629 mm-1 . 展开更多
关键词 SALICYLALDEHYDE o-aminobenzoic acid crystal structure one-dimensional chain N-salicylidene-2-amino-phenylacidato copper(Ⅱ)
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Crystallographic Parameters and Band Gap of CdSxSe1-x Mixed Crystals
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作者 Abdullah A. Al-Bassam Usamh A. Elani 《Journal of Energy and Power Engineering》 2014年第4期770-774,共5页
Crystals of CdSxSe1-x alloys have been grown from the vapour phase. Some of the physical properties, such as lattice parameters, crystal structure and x-rays data of CdSxSe1-x alloys were determined using x-ray diffra... Crystals of CdSxSe1-x alloys have been grown from the vapour phase. Some of the physical properties, such as lattice parameters, crystal structure and x-rays data of CdSxSe1-x alloys were determined using x-ray diffractometry. X-ray diffractometry has shown that CdS-CdSe mixed crystals had the wurtzite structure for all compositions between CdS and CdSe. The lattice parameters (both a and c) were found to show a linear dependence with composition. The dependence of the lattice parameters of a and c on composition can be expressed as: a(x) = 4.165 + 0.16x; c(x) = 6.713 + 0.27x. The variation of band gap with composition was determined for these samples from optical absorption measurements, which showed that the band gap varied smoothly and monotonically, but not linearly over the composition range typical results were found between 2.42-1.74 eV at room temperature. 展开更多
关键词 Thin films mixed crystals lattice parameter SEMICONDUCTORS devices.
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Visible-Light Activities of Erbium Doped BiVO4 Photocatalysts
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作者 张爱平 张进治 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期73-78,I0002,共7页
Er-doped BiVO4 composite photocatalyst was hydrothermal synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray Spectroscopy, X-ray photoelectron spectroscopy, ... Er-doped BiVO4 composite photocatalyst was hydrothermal synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray Spectroscopy, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectra techniques. The activity of the catalyst was determined by oxidative decomposition of methyl orange in aqueous solution under visible-light irradiation. X-ray photoelectron spectroscopy and energy-dispersive X-ray Spectroscopy analysis revealed that the doped Er existed in the form of Er2O3. It also showed that the Er doping can enhance the visible-light absorption abilities of catalysts and their visible-light-driven photocatalytic activities in comparison with those of pure BiVO4. 展开更多
关键词 PHOTOCATALYSIS Composite photocatalyst VISIBLE-LIGHT
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The Mineral Transformation of Huainan Coal Ashes in Reducing Atmospheres 被引量:9
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作者 LI Han-xu Yoshihiko Ninomiya +1 位作者 DONG Zhong-bing ZHANG Ming-xu 《Journal of China University of Mining and Technology》 2006年第2期162-166,共5页
By using the advanced instrumentation of a Computer Controlled Scanning Electron Microscope (CCSEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF), the ash composition and the mineral components of six ty... By using the advanced instrumentation of a Computer Controlled Scanning Electron Microscope (CCSEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF), the ash composition and the mineral components of six typical Huainan coals of different origins were studied. The transformation of mineral matter at high temperatures was tracked by XRD in reducing conditions. The quartz phase decreased sharply and the anorthite content tended to increase at first and then decreased with increasing temperatures. The formed mullite phase reached a maximum at 1250 ℃ but showed a tendency of slow decline when the temperature was over 1250 ℃. The mullite formed in the heating process was the main reason of the high ash melting temperature of Huainan coals. Differences in peak intensity of mullite and anorthite reflected differences in phase concentration of the quenched slag fractions, which contributed to the differences in ash melting temperatures. The differences in the location of an mnorphous hump maximum indicated differences of glass types which may affect ash melting temperatures. For Huainan coal samples with relatively high ash melting tempera- tures, the intensity of the diffraction lines for mullite under reducing condition is high while for the samples with relatively low ash melting temperature the intensity for anorthite is high. 展开更多
关键词 crystalline component xRD Huainan coal ash melting
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Development of 3D crystallographic orientation measurement for grain deformation analysis in aluminum alloy 被引量:1
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作者 M.KOBAYASHI H.TODA +4 位作者 D.J.LECLERE T.KAMIKO K.UESUGI A.TAKEUCHI Y.SUZUKI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2094-2101,共8页
Development of inhomogeneous deformation is an interest matter in material engineering. Synchrotron radiation tomography provides 3D distribution map of local strain in polycrystalline aluminum alloy by tracking micro... Development of inhomogeneous deformation is an interest matter in material engineering. Synchrotron radiation tomography provides 3D distribution map of local strain in polycrystalline aluminum alloy by tracking microstructural features. To perform further deep analysis on development of inhomogeneous deformation, crystallographic grain orientation is necessary. Three-dimensional X-ray diffraction technique was developed. A new crystallographic orientation measurement method was described in 3D space, utilizing grain boundary tracking (GBT) information. 展开更多
关键词 synchrotron radiation x-ray tomography x-ray diffraction plastic deformation crystallographic orientation
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Reactive Adsorption of Thiophene on ZnNi/Diatomite-Pseudo-Boehmite Adsorbents 被引量:2
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作者 Meng Xuan Weng Huixin Shi Li 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2012年第3期33-38,共6页
The thiophene removal ability of the synthesized ZnNi/diatomite-pseudo-boehmite adsorbent was tested in a lab- scale fixed-bed reaction system. X-ray diffractograms (XRD) were used to characterize the adsorbent samp... The thiophene removal ability of the synthesized ZnNi/diatomite-pseudo-boehmite adsorbent was tested in a lab- scale fixed-bed reaction system. X-ray diffractograms (XRD) were used to characterize the adsorbent samples. The effects of Zn/Ni molar ratio, various model fuels and regeneration patterns on the RADS tests were studied. The adsorption mecha- nism was investigated by XRD and MS analyses. The results indicted that thiophene in the model fuel was first decomposed on the surface Ni of the adsorbent to form Ni3S2 while the hydrocarbon portion of the molecule was released back into the process stream, followed by reduction of Ni3S2 to form H2S in the presence of H2, and then HzS is stored in the adsorbent accompanied by the conversion of ZnO into ZnS. 展开更多
关键词 reactive adsorption DESULFURIZATION THIOPHENE OLEFIN REGENERATION
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Synthesis and Study of Heteronuclear Citrates 被引量:1
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作者 Nani Bldzlna Zhorzhohani Iamze Alim Beshkenadze Maia Avtandil Gogaladze Givi Tengiz Begheluri 《Journal of Chemistry and Chemical Engineering》 2014年第4期385-389,共5页
Terms of synthesis were determined for creation of new generation premixes and for their testing in experiments. Heteronuclear chelate citrates of general formula: M12MnL2.nH2O (where, M^I = Zn, Co, Fe, Mn, Cu; MH =... Terms of synthesis were determined for creation of new generation premixes and for their testing in experiments. Heteronuclear chelate citrates of general formula: M12MnL2.nH2O (where, M^I = Zn, Co, Fe, Mn, Cu; MH = Mn, Zn, Co, Cu; n = 0/4) were synthesized. Identity and composition of synthesized compounds were defined by microelemental analysis, determination of melting temperature and X-ray diffraction analysis. X-ray diffraction method was used also to define crystallinity of the compounds and their citric acid (H4L) component. X-ray amorphous and iso-structural orders were also revealed. 展开更多
关键词 Bio-metals chelate compounds microelemental analysis x-ray diffraction analysis.
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Preparation and characterization of sulfated TiO_2 with rhodium modification used in esterification reaction and decomposition of methyl orange 被引量:3
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作者 Yu Niu Fuying Li +3 位作者 Kai Yang Ting Qiu Renzhang Wang Cheng Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第6期767-774,共8页
A unique Rh/TiO2 solid acid catalyst modified with H2S04 was synthesized and evaluated in the esterification reaction of propylene glycol methyl ether and decomposition of methyl orange (MO) in aqueous phase under h... A unique Rh/TiO2 solid acid catalyst modified with H2S04 was synthesized and evaluated in the esterification reaction of propylene glycol methyl ether and decomposition of methyl orange (MO) in aqueous phase under halogen lamp irradiation. For this purpose, rhodium (Rh) nanoparticles were loaded on S02-/Ti02 via the photo-deposition method. It was found that S024-/Rh-Ti02 exhibited stronger catalytic activity than S02-/ Ti02. The new catalysts were characterized by X-ray powder diffraction (XRD), Brunauer-Emmett-Teller (BET), Transmission electron microscopy (TEM) and high-resolution (HRTEM), X-ray photoelectron spec- troscopy (XPS) and Fourier Transform infrared spectroscopy (FrlR). Results from XRD and BET show that S02-/Rh-Ti02 has higher specific surface area and smaller pore size than S02-fri02. The distribution of loaded Rh was found to be uniform with a particle size of 2-4 nm. Data from XPS reveal that Rh primarily exists as Rh~ and Rh3 + in Rh-Ti02 and SO^-/Rh-TiO~. These valence forms of Rh likely contribute to the en- hanced catalytic activity. Furthermore, FT-IR spectra of the catalysts show an abundance of surface hydroxyl groups, which help the formation of hydroxyl radicals and the enhancement of surface acid density. The results show that more acid sites are formed on the sulfated Rh-Ti02, and these acidic sites are largely responsible for improving the catalytic performance. This superior SO]-/Rh-Ti02 catalyst has potential applications in reactions reouirinz efficient acid catalysts, includinz esterification reactions and waste water treatment. 展开更多
关键词 RhodiumEsterification reactionSO2 /Ti02Photo-depositionMethyl orange
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Temperature dependence on reaction of CaCO_3 and SO_2 in O_2/CO_2 coal combustion
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作者 王宏 徐辉碧 +1 位作者 郑楚光 邱建荣 《Journal of Central South University》 SCIE EI CAS 2009年第5期845-850,共6页
The temperature dependence on the reaction of desulfurization reagent CaCO3 and SO2 in O2/CO2 coal combustion was investigated by thcrmogravimetric analysis, X-ray diffraction measurement and pore structure analysis. ... The temperature dependence on the reaction of desulfurization reagent CaCO3 and SO2 in O2/CO2 coal combustion was investigated by thcrmogravimetric analysis, X-ray diffraction measurement and pore structure analysis. The results show that the conversion of the reaction of CaCO3 and SO2 in air is higher at 500-1 100 ℃ and lower at 1 200 ℃ compared with that in O2/CO2 atmosphere. The conversion can be increased by increasing the concentration of SO2, which causes the inhibition of CaSO4 decomposition and shifting of the reaction equilibrium toward the products. XRD analysis of the product shows that the reaction mechanism of CaCO3 and SO2 differs with temperature in O2/CO2 atmosphere, i.e. CaCO3 directly reacts with SO2 at 500 ℃ and CaO from CaCO3 decomposition reacts with SO2 at 1 000 ℃. The pore analysis of the products indicates that the maximum specific surface area of the products accounts for the highest conversion at 1 100 ℃ in O2/CO2 atmosphere. The results reveal that the effect of the atmosphere on the conversion is temperature dependence. 展开更多
关键词 CACO3 SO2 O2/CO2 coal combustion temperature dependence
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Liquidus and phase equilibria in CaO-SiO2-5%MgO-20%Al2O3-TiO2 system
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作者 孙丽枫 石俊杰 +3 位作者 张波 邱吉雨 王昭云 姜茂发 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期48-55,共8页
The single hot thermocouple technique (SHTT) and high temperature equilibrium technique were combined to investigate the phase diagram of the CaO-SiO2-5%MgO-20%AlzO3-TiO2 system. The 1300 ℃ to 1500 ℃ liquidus line... The single hot thermocouple technique (SHTT) and high temperature equilibrium technique were combined to investigate the phase diagram of the CaO-SiO2-5%MgO-20%AlzO3-TiO2 system. The 1300 ℃ to 1500 ℃ liquidus lines are calculated according to the thermodynamic equations based on the pseudo-melting temperatures measured by the single hot thermocouple technique. The phase equilibria relationships are experimentally determined at 1400 ℃ using the high temperature equilibria technique followed by X-ray fluorescence (XRF), X-ray diffraction(XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analysis. The liquid phase(L), melilite solid solution phase ((C2MSz,C2AS)ss), diopside phase(CMS2) and perovskite phase (CaO·TiO2) are found. Coupled with the liquidus lines and equilibria results, the phase diagram is constructed for the specified region of the CaO-SiO2-5%MgO-20%Al2O3-TiO2 system. 展开更多
关键词 phase diagram LIQUIDUS EQUILIBRIUM TiO2 single hot thermocouple technique (SHTT) THERMODYNAMICS
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Preparation High-Temperature Behavior of Conversion Coating of Alumina Film on FeCrAI (Ce) Stainless Steel
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作者 H. Essom 《Journal of Chemistry and Chemical Engineering》 2012年第12期1083-1092,共10页
FeCrAI (Ce) stainless steel was functionalized by a conversion treatment in order to allow alumina by diffusion coatings with strong interfacial bonding. The very porous conversion coating produced in a pack alumini... FeCrAI (Ce) stainless steel was functionalized by a conversion treatment in order to allow alumina by diffusion coatings with strong interfacial bonding. The very porous conversion coating produced in a pack aluminization technique had excellent adhesion and was conductive enough to permit conditions favorable for the precipitation of alumina oxyhydroxide during aluminum diffusion coatings. In this work, the bed was prepared as a mixture of A1, NH4C1 and A1203. In the high-activity bed were heat-treated at 1,173 K in an atmosphere made up of team with subsequent air-cooling. The effect of the bed content on the coating was examined. With the high-activity, the desired Fe2Al5 was formed as the outermost coating layer. The coating presented chemical composition gradients suitable for strong adhesion. The improvement of the thermal oxidation behaviour was studied at 1,373 K. Two different aqueous environments, which are (1) NaC1 and (2) H2SO4, are employed for using the technique of potentiodynamic polarization curve. The obtained experimental electrochemical parameters (Ecorr, Jcorr etc,) were used to compare the corrosion resistance of the tested steel state complemented by MEB (electronic scanning microscopy) in combination with dispersive analysis X in energy (EDS) or X ray diffraction indicated that the elements concentration maximum was located in the vicinity of the interface especially in the FeCrAI (Ce) coated by spherical A1203 powder. These results an discussed in terms of an addition effect on the development of the microstructure of oxide films. 展开更多
关键词 COATING ALUMINA corrosion MORPHOLOGY heat treatment adhesion.
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Gas adsorption in shaped zeolitic imidazolate framework-8
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作者 朱吉钦 江璐 +2 位作者 代成娜 杨娜 雷志刚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第8期1275-1282,共8页
Zeolitic imidazolate framework-8(ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The in fluence of the shaping conditions on the microstructure of the shaped samp... Zeolitic imidazolate framework-8(ZIF-8) was prepared through a solve-thermal reaction method and then shaped using different additives. The in fluence of the shaping conditions on the microstructure of the shaped samples was characterized by the XRD, BET, and SEM techniques. The results demonstrate that the compressive strength of the various shaped tablets is greatly increased and capable of meeting the industrial requirements compared to the unshaped ZIF-8 and that the loss rate of speci fic surface areas was maintained at 10% after the addition of 10%(by mass) binder and 10%(by mass) solvent. The adsorption isotherms of CO2, CH4, C3H8, and C3H6 on powdery ZIF-8and the shaped tablets(T-shaped ZIF-8, C-shaped ZIF-8, and N-shaped ZIF-8) were determined through volumetric measurements under different pressures and temperatures(298.2, 323.2, and 348.2 K). The adsorption capacities of the gases on both the ZIF-8 powder and the shaped tablets follow the order C3H6 N C3H8N CO2 N CH4. Furthermore,the results show that the adsorption capacities of the gases on the shaped tablets are lower by approximately 10%–20% than those on the powdery ZIF-8. In fact, the adsorption equilibrium isotherms for CO2, CH4, C3H8, and C3H6 on both powdery and shaped ZIF-8 can be well described by the Langmuir equation. 展开更多
关键词 ZIF-8 Shaping Gas adsorption Model reduction Materials
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Adsorption behavior of petroleum asphaltenc Adsorption model
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作者 ZHANG Lei QUE Guo-he DENG Wen-an ZHAO Li-wa 《Journal of Chemistry and Chemical Engineering》 2009年第4期53-58,共6页
Asphaltene is one of the most heavy components, asphaltene adsorption is a serious problem in oil production and processing. In this paper, the progress in the investigation of asphaltene adsorption from the aspects o... Asphaltene is one of the most heavy components, asphaltene adsorption is a serious problem in oil production and processing. In this paper, the progress in the investigation of asphaltene adsorption from the aspects of adsorption model and adsorption behavior is reviewed. Asphaltene of adsorption model include the Langmuir, Freundlich, Langmuir-Freundlich, Rcdlich-Pctcrson, BET adsorption isothcrm. The adsorption behavior of asphaltene was characterized by a variety of structure-probing methods such as N:-adsorption, X-ray diffraction (XRD), small-angle X-ray scattering (SAXS) measurements, and FT-IR spectroscopy. To understand better the adsorption progress of petroleum, asphaltene must understand the whole adsorption behavior of asphaltene. 展开更多
关键词 petroleum asphaltene adsorption model Freundlich model Langmuir model
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