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Influence of substituting B_(2)O_(3) with Li_(2)O on the viscosity,structure and crystalline phase of low-reactivity mold flux

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1320-1328页

作者： Rongzhen Mo Xubin Zhang Ying Ren Junjie Hu Lifeng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Lecture at College of Materials Science and Engineering Chongqing UniversityChongqing 400030China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The low-reactivity mold flux with low SiO_(2)content is considered suitable for the continuous casting of high-aluminum steel since it can significantly reduce the reaction between Al in steel and SiO_(2)in mold ***,the traditional low-reactivity mold flux still presents some problems such as high viscosity and strong crystallization *** this study,the co-addition of Li_(2)O and B_(2)O_(3)in CaO–Al_(2)O_(3)–10wt%Si O_(2)based low-reactivity mold flux was proposed to improve properties of mold flux for high-aluminum steel,and the effect of Li_(2)O replacing B_(2)O_(3)on properties of mold flux was *** viscosity of the mold flux with 2wt%Li_(2)O and 6wt%B_(2)O_(3)reached a minimum value of 0.07 Pa·*** break temperature and melting point showed a similar trend with the ***,the melt structure and precipitation of the crystalline phase were studied using Raman and X-ray diffraction spectra to better understand the evolution of *** demonstrated that with increasing Li_(2)O content in the mold flux from 0 to 6 wt%,the degree of polymerization of aluminate and the aluminosilicate network structure increased because of increasing Li+released by Li_(2)O,indicating the added Li_(2)O was preferentially associated with Al^(3+)as a charge *** precipitation of LiAlO_(2)crystalline phase gradually increased with the replacement of B_(2)O_(3)by Li_(2)***,Li_(2)O content should be controlled below 2wt%to avoid LiAlO_(2)precipitation,which was harmful to the continuous casting of highaluminum steels.

关键词： low-reactivity mold flux viscosity structure crystalline phase

Effect of ZrO_2 crystalline phase on the Performance of Ni-B/ZrO_2 Catalyst for the CO Selective Methanation

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Chinese Journal of Chemical Engineering 2011年第3期19卷 434-438页

作者：刘其海廖列文刘自力董新法 School of Chemistry and Chemical Engineering ZhongKai University of Agriculture and Engineering School of Chemistry and Chemical Engineering Guangzhou University School of Chemistry and Chemical Engineering South China University of Technology

Amorphous Ni-B/ZrO2 catalysts were prepared by coprecipitation-chemical reduction with KBH4 aqueous solution,and various crystalline phase ZrO2(amorphous-ZrO2,tetragonal-ZrO2 and monoclinic-ZrO2) supported Ni-B catalysts were obtained by thermal treatment in 5%H2-N2 stream at different *** effect of ZrO2 polymorphs and the treatment temperature on the catalytic performance for the CO selective methanation were investigated,and the catalysts were characterized by N2 physisorption,Powder X-ray diffraction(XRD), Temperature-Programmed Desorption(CO-TPD and H2-TPD),and Differential Scanning Calorimeter(DSC).The treatment temperature affected strongly the crystalline structure of ZrO2,and the CO methanation activity and selectivity of the Ni-B/ZrO2 catalysts were significantly influenced by the crystalline phase of *** the three forms of ZrO2 polymorphs(amorphou-ZrO2,tetragonal-ZrO2 and monoclinic-ZrO2),the amorphous-ZrO2 supported nickle catalyst showed highest CO methanation activity,attributing in large part to the largest specific surface area and the optimum CO/H2 absorption intensity of the Ni-B/amorphous-ZrO2 catalyst.

关键词： crystalline phase carbon monoxide selective methanation Ni-B/ZrO2 catalyst

The Formula of Dependence of Mechanical Characteristics of Materials on crystalline phase Composition in the Matrix

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Advances in Materials Physics and Chemistry 2020年第8期10卷 178-188页

作者： Z. Kovziridze Institute of Bionanoceramics and Nanocomposite Technology Georgian Technical University Tbilisi Georgia

Objective: For materials science and generally, for long-term operation of work-pieces in industry the significant role is attributed to dependence of macro-mechanical properties of consolidated body on crystalline phase composition, its dimensions, form, distribution in matrix and the form factor. While working in responsible fields of technology of ceramics and ceramic composites the above referred properties are attributed extremely great role with the view of durability and endurance at the terms of heavy mechanical loads. For description of the resistance of any concrete type work-piece, the crystalline phase plays the greatest role in mechanical strength or deformation of any material. It plays the important role in correlative explanation of materials mechanics and matrix properties. In our case, in the process of destruction of ceramic materials and composites, which will give us exhaustive response to the role of macro- and micro-mechanical properties of materials, the role of a macro- and micro-structural component, that is, of crystalline phase in the process of transition of stable state of materials into meta-stable state is extremely big. Our study aims to develop a formula of dependence of macro-mechanical properties of ceramic and ceramic composites on crystalline phase, the most powerful component of their structure, which will enable theorists and practitioners to select and develop technologies and technological processes correctly. Method: On the basis of the study of micro- and macro-mechanical properties of ceramics and ceramic composites and the morphology of crystalline phase and the analysis of the study we determined and created parameters of the formula. Results: The formula covers macro-mechanical properties, that is when the work-piece is thoroughly destructed: mechanic at bending at three and four-point load, mechanic at contraction;among morphological characteristics: composition of cr

关键词： crystalline phase Macro-Mechanical Properties Mechanic at Bending Mechanic at Compaction Factor of Spreading of crystalline phase in Matrix

crystalline-phase-dependent catalytic performance of MnO_2 for aerobic oxidation reactions

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Science China Materials 2017年第12期60卷 1196-1204页

作者：徐杨正黄剑楠杨圣双王建凤陈伟陈艳马德琨杨云黄少铭 Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou University School of Materials and Energy Guangdong University of Technology

Knowledge of the catalytic performances of different crystalline phases of a material is vital for the development of superior catalysts. In this study, different phases of MnO2 （（α,β,γ and δ） have been prepared by the oxidation of Mn^2＋, and their catalytic performances were evaluated using the aerobic oxidation of benzyl alcohol to benzaldehyde as a model reaction, α-MnO2 promoted the reaction to the highest yield. However, when the yields were normalized by the corresponding surface areas, δ-MnO2 exhibited the highest specific activity and a-MnO2 the lowest, indicating that the diverse microstructures resulting from the crystalline phase have a profound effect on catalytic performance, α-MnO2 showed the highest catalytic stability, resulting from its unchanged composition and morphology after use. Informed by the experimental results, a possible reaction mechanism involving the Mars-van Krevelen process was proposed. This work provides useful information for the development of effective catalysts for aerobic oxidation.

关键词： crystalline phase MnO2 aerobic oxidation

Hydroxyapatite-modified micro/nanostructured titania surfaces with different crystalline phases for osteoblast regulation

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Bioactive Materials 2021年第4期6卷 1118-1129页

作者： Pinliang Jiang Yanmei Zhang Ren Hu Xiankuan Wang Yuekun Lai Gang Rui Changjian Lin College of Materials Xiamen UniversityXiamen361005China State Key Lab of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China National Engineering Research Center of Chemical Fertilizer Catalyst(NERC-CFC) College of Chemical EngineeringFuzhou UniversityFuzhou350116China Department of Orthopedics Surgery The First Affiliated Hospital of Xiamen UniversityXiamen361003China

Surface structures and physicochemical properties critically influence osseointegration of titanium(Ti)*** studies have shown that the surface with both micro-and nanoscale roughness may provide multiple features comparable to cell dimensions and thus efficiently regulate cell-material ***,less attention has been made to further optimize the physicochemical properties(e.g.,crystalline phase)and to further improve the bioactivity of micro/nanostructured ***,micro/nanostructured titania surfaces with different crystalline phases(amorphous,anatase and anatase/rutile)were prepared and hydroxyapatite(HA)nanorods were deposited onto the as-prepared surfaces by a spin-assisted layer-by-layer assembly method without greatly altering the initial multi-scale morphology and *** effects of crystalline phase,chemical composition and wettability on osteoblast response were *** is noted that all the micro/nanostructured surfaces with/without HA modification presented *** activities of MC3T3-E1 cells suggested that the proliferation trend on the micro/nanostructured surfaces was greatly influenced by different crystalline phases,and the highest proliferation rate was obtained on the anatase/rutile surface,followed by the anatase;but the cell differentiation and extracellular matrix mineralization were almost the same among *** ultrathin HA modification on the micro/nanostructured surfaces with different crystalline phases,it exhibited similar proliferation trend as the original surfaces;however,the cell differentiation and extracellular matrix mineralization were significantly *** results indicate that the introduction of ultrathin HA to the micro/nanostructured surfaces with optimized crystalline phase benefits cell proliferation,differentiation and maturation,which suggests a favorable biomimetic microenvironment and provides the potential for enhanced implant osseointegration in vi

关键词： Micro/nanostructured surfaces crystalline phase Hydroxyapatite Cell response Bioactivity

The effect of annealing temperature and film thicknesson the phase of pentacene on the p^+-Si substrate

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Chinese Physics B 2008年第10期17卷 3822-3826页

作者：袁广才徐征赵谡玲张福俊黄金昭黄金英田雪雁徐叙瑢 Institute of Optoelectronic Technology Beijing Jiaotong University ChinaKey Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education

This paper investigates the morphology and crystallization properties of the two crystalline phases of pentacene grown by thermal evaporation on p^＋-Si substrates at room temperature by the methods of atomic force microscopy and x-ray diffraction. This kind of substrate induces a thin film phase and a triclinic phase which are formed directly onto p^＋-Si substrates and constitute a layer consisting of faceted grains with a step height between terraces of 15.8A（1A=0.1 nm） and 14.9A, respectively. Above the critical thickness of the thin film phase, lamellar structures are found with an increasing fraction with the increase of the film thickness. When the film thickness is fixed, the fraction of lamellar structures increases with the increase of annealing temperature. These lamellar structures are identified as the second phase with a interplanar distance of 14.9A corresponding to the pentacene triclinic phase. Furthermore, the thin film phase consisting of several micrometre sized uniformly oriented grains at an annealing temperature of less than 80℃ and a deposition rate of 0.6A/s is observed.

关键词： pentacene morphology crystalline phase thin-film transistors

微观尺度下聚偏二氟乙烯介电性能的晶相依赖性（英文）

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微观尺度下聚偏二氟乙烯介电性能的晶相依赖性（英文）

Microstructure and magnetic properties of electrodeposited Gd-Co alloy films

2024第五届全国功能高分子材料学术研讨会

作者：苏梦悦周峻陈雨晴郭皓敏张梓轩王奕隆金赣吴锴西安交通大学电工材料电气绝缘国家重点实验室可再生能源纳米材料研究中心

The polyvinylidene fluoride(PVDF) consists of various phases that can be transformed into each *** crystal phases each have specific physical and chemical properties appropriate for various industrial ***,the mapping relationship between specific phases and physical properties remains challenging,resulting in a lack of understanding of the morphology relationship characteristics in *** this work,PVDF with two typical crystalline phases(αandβ) has been synthesized by a modified solution method at different ***-situ Kelvin probe force microscopy(KPFM) and Piezoelectric force microscopy(PFM) were employed to investigate the responses of different PVDF crystalline phases to dielectric,charge mobility,and polarization *** morphology of αphase is confirmed to be dendrite with a small charge injection barrier and higher charge decay rate,while βphase demonstrates as spherulite with a smaller relative permittivity(ε')and lower charge ***,a clear reversible transformation of polarization occurs in the spherulite phase under a ±10 V bias,consistent with its polar intrinsic *** work provides deep insights into understanding the crystalline morphology of PVDF significantly correlates with physical-chemical properties such as molecular conformation,crystalline phase components,and dielectric properties.

关键词： Polyvinylidene fluoride(PVDF) crystalline phase Kelvin probe force microscopy(KPFM) Charge injection Dielectric

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Rare Metals 2008年第6期27卷 586-590页

作者： LAI Heng LI Jiaxin ZHOU Weichao ZHUANG Bin WU Xiaoping HUANG Zhigao Shool of Physics and Optoelectronics Technology Fujian Normal University Fuzhou 350007 China Department of Chemistry Fuzhou University Fuzhou 350002 China

Gd-Co alloy films were synthesized by potentiostatic electrolysis on Cu substrates in urea-acetamide-NaBr-KBr melt at 353 K. The electroreduction of Co^2＋ and Gd^3＋ was investigated by cyclic voltammetry. The reduction of Co^2＋ is an irreversible process. Gd^3＋ cannot be reduced alone, but it can be inductively co-deposited with Co^2＋. Both the Gd content and microstructure of the prepared Gd-Co alloy films can be controlled by the deposited potential. The content of Gd was analyzed using an inductively coupled plasma emission spectrometer （ICPES）, and the microstructure was observed by scanning electron micrograph （SEM）. The films were crystallized by heat-treatment at 823 K for 30 s in Ar atmosphere, and then were investigated by XRD. The hysteresis loops of the Gd-Co alloy films were measured by a vibrating sample magnetometer （VSM）. The experimental results reveal that the deposited Gd-Co alloy films are amorphous, while the annealing causes the samples to change from amorphous to polycrystalline, thus enhancing their magnetocrystalline anisotropy and coercivity. Moreover, the magnetic properties of the Gd-Co alloy films depend strongly on the Gd content.

关键词： electrodeposited films Gd-Co alloys surface microstructure crystalline phase magnetic properties

Influence of Fe_2O_3 and V_2O_5 on crystalline Structure of Mg-Al Spinel Synthesized by Waste Aluminum Slag

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Chinese Journal of Structural Chemistry 2007年第6期26卷 659-663页

作者：郑韵虹阮玉忠于岩吴任平 School of Materials Science and Engineering Fuzhou University

Mg-Al spinel is synthesized by using industrial waste-residue and basic magnesium carbonate in the aluminum factory as the main raw materials. The influence of V2O5 and Fe2O3 mineralizers on the structure, cell parameters and microscopic morphology of synthesized Mg-Al spinel has been discussed. The Mg-Al spinel is characterized by using XRD, SEM and relevant analytical software, such as Philips plus, Rietveld quantification and so on. The experimental results show that certain amounts of V2O5 and Fe2O3 are beneficial to the formation of Mg-Al spinel, and the optimum addition of V2O5 and Fe2O3 is respectively 2wt% and 3wt%. V2O5 has few effects on cell parameters of Mg-Al spinel; but Fe2O3 can form solid solution with Mg-Al spinel in which Mg-Fe spinel can also dissolve to form continuous solid solution. Therefore, with the increase of Fe2O3 content, the cell parameters of Mg-Al approximately present linear increase.

关键词： Mg-Al spinel mineralizer crystalline phase cell parameters