检索结果-南通市图书馆

A High-Accuracy Curve Boundary Recognition Method Based on the Lattice Boltzmann Method and Immersed Moving Boundary Method

引用

Computer Modeling in Engineering & Sciences 2024年第9期140卷 2533-2557页

作者： Jie-Di Weng Yong-Zheng Jiang Long-Chao Chen Xu Zhang Guan-Yong Zhang hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment Hunan University of Science and TechnologyXiangtan411201China School of Mechanical Engineering Hunan Chemical Vocational Technology CollegeZhuzhou412000China

Applying numerical simulation technology to investigate fluid-solid interaction involving complex curved bound-aries is vital in aircraft design,ocean,and construction ***,current methods such as Lattice Boltzmann(LBM)and the immersion boundary method based on solid ratio(IMB)have limitations in identifying custom curved ***,IBM based on velocity correction(IBM-VC)suffers from inaccuracies and numerical ***,this study introduces a high-accuracy curve boundary recognition method(IMB-CB),which identifies boundary nodes by moving the search box,and corrects the weighting function in LBM by calculating the solid ratio of the boundary nodes,achieving accurate recognition of custom curve *** addition,curve boundary image and dot methods are utilized to verify *** findings revealed that IMB-CB can accurately identify the boundary,showing an error of less than 1.8%with 500 ***,the flow in the custom curve boundary and aerodynamic characteristics of the NACA0012 airfoil are calculated and compared to *** showed that IMB-CB yields lower lift and drag coefficient errors than IBM-VC,with a 1.45%drag coefficient *** addition,the characteristic curve of IMB-CB is very stable,whereas that of IBM-VC is *** the moving boundary problem,LBM-IMB-CB with discrete element method(DEM)is capable of accurately simulating the physical phenomena of multi-moving particle flow in complex curved *** research proposes a new curve boundary recognition method,which can significantly promote the stability and accuracy of fluid-solid interaction simulations and thus has huge applications in engineering.

关键词： Fluid-solid interaction curve boundary recognition method Lattice Boltzmann method immersed moving boundary method

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Electrocatalytic oxidation behavior of L-cysteine at Pt microparticles modified nanofibrous polyaniline film electrode

引用

Journal of Central South University of technology 2008年第2期15卷 170-175页

作者：马淞江罗胜联周海晖旷亚非宁晓辉 college of Chemistry and chemical Engineering Hunan University of Science and Technology college of Chemistry and chemical Engineering Hunan University

Platinum(Pt)/nanofibrous polyaniline(PANI) electrode was prepared by pulse galvanostatic method and characterized by scanning electron *** electrochemical behavior of L-cysteine at the Pt/nanofibrous PANI electrode was investigated by cyclic *** results indicate that the pH value of the solution and the Pt loading of the electrode have great effect on the electrocatalytic property of the Pt /nanofibrous PANI electrode;the suitable Pt loading of the electrode is 600 μg/cm2 and the suitable pH value of the solution is 4.5 for investigating L-cysteine *** L-cysteine sensor based on the Pt/nanofibrous PANI electrode has a good selectivity,reproducibility and *** Pt/nanofibrous PANI electrode is highly sensitive to L-cysteine,and the linear calibration curve for the oxidation of L-cysteine can be observed in the range of 0.2-5.0 mmol/L.

关键词： electrocatalytic oxidation electrode polyaniline platinum L-cysteine nanofibre

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of praseodymium on catalytic graphitization of furan resin carbon

引用

Journal of Rare Earths 2010年第1期28卷 69-71页

作者：易守军陈金华肖雄刘露樊桢 college of Chemistry and chemical Engineering Hunan University School of Chemistry and chemical Engineering Hunan University of Science and Technology

We introduced a new catalyst,rare earth element praseodymium,for the catalytic graphitization of furan resin *** extent of graphitization of the furan resin carbon was examined by X-ray diffraction and Raman *** morphology of furan resin carbon was characterized by scanning electron *** effects of the praseodymium content and the heat-treatment temperature on the catalytic graphitization of furan resin carbon were also *** results indicated that the praseodymium c...

关键词： catalytic graphitization praseodymium furan resin X-ray diffraction Raman spectroscopy rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Synthesis and Characterization of Li_(1.05)Co_(0.3)Ni_(0.35)Mn_(0.3)M_(0.05)O_2(M=Ge,Sn)Cathode Materials for Lithium Ion Battery

引用

Journal of Wuhan University of technology(Materials Science) 2012年第2期27卷 212-216页

作者：陈玉红申玉双 Department of chemical and Environmental Engineering Hebei Chemical & Pharmaceutical Vocational Technology College

In order to improve the electrochemical performance and thermal stability of Li1.05Co1/3Nil/3Mnl/302 materials, Lil.05CO0.3 Ni0.35Mno.3Mo.0502（M=Ge,Sn） cathode materials were synthesized via co-precipitation method. The structure, electrochemical performance and thermal stability were characterized by X-ray diffraction（XRD）, charge/discharge cycling, cyclic voltammetry（CV）, electrochemical impedance spectroscopy（EIS） and differential scanning calorimetry（DSC）. ESEM showed that Sn-doped and Ge- doped slightly increased the size of grains. XRD and CV showed that Sn-doped and Ge-doped powders were homogeneous and had the better layered structure than the bare one. Sn-doped and Ge-doped improved high rate discharge capacity and cycle-life performance. The reason of the better cycling performance of the doped one was the increasing of lithium-ion diffusion rate and charge transfer rate. Sn-doped and Ge-doped also improved the mateials thermal stability.

关键词： lithium-ion batteries cathode materials Gedoped Sn-doped coprecipitation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

La-EDTA coated Fe_3O_4 nanomaterial:Preparation and application in removal of phosphate from water

引用

Journal of Environmental Sciences 2013年第2期25卷 413-418页

作者： Jiao Yang Qingru Zeng Liang Peng Ming Lei Huijuan Song Boqing Tie Jidong Gu Department of Environmental Science&Engineering Hunan Agricultural University School of Metallurgical Science and technology Central South University hunan Perochemical vocational technology college

La-EDTA-Fe3O4 was prepared by a chemical co-precipitation method. The magnetic composite was characterized by transmission electron microscopy （TEM）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FT-IR）. Furthermore, the adsorption properties of La-EDTA-Fe3O4 toward phosphate in water were investigated. The uptake rate of phosphate in water by La-EDTA-Fe3O4 was 3-1000 times than that of EDTA-Fe3O4, and reached 97.8% at 7 hr. The adsorption process agreed well with the Freundlich model and kinetics studies showed that the adsorption of phosphate proceeds according to pseudo second-order adsorption kinetics. The maximum removal rate was achieved at pH 6.0-7.0. The La-EDTA-Fe3O4 had good adsorption properties and could be separated well from aqueous solution by a permanent magnet. Therefore, this nanomaterial has potential application for the removal of phosphate from large water bodies.

关键词： La-EDTA-Fe3O4 phosphate magnetic materials

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation of anodic films on 2024 aluminum alloy in boric acid-containing mixed electrolyte

引用

中国有色金属学会会刊：英文版 2008年第4期18卷 825-830页

作者：马淞江罗鹏周海晖付超鹏旷亚非 college of Chemistry and chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China college of Chemistry and chemical Engineering Hunan UniversityChangsha 410082China

The anodizing oxidation process on 2024 aluminum alloy was researched in the mixed electrolyte with the composition of 30 g/L boric acid, 2 g/L sulfosalicylic acid and 8 g/L phosphate. The results reveal that the pre-treatment and the composition of the mixed electrolyte have influence on the properties of the films and the anodizing oxidation process. Under the condition of controlled potential, the anodizing oxidation current—time response curve displays "saddle" shape. First, the current density reaches a peak value of 8-20 A/dm2 and then decreases rapidly, finally maintains at 1-2 A/dm2. The film prepared in the mixed electrolyte is of porous-type with 20 nm in pore size and 500 μm-2 in porosity. Compared with the conventional anodic film obtained in sulfuric acid, the pore wall of the porous layer prepared in this work is not continuous, which seems to be deposited by small spherical grains. This porous structure of the anodic film may result from the characteristics of the mixed electrolyte and the special anodizing oxidation process. The surface analysis displays that the anodic film is amorphous and composed of O, Al, C, P, S, Si and no copper element is detected.

关键词： 2024铝合金硼酸混合电解液阳极电镀阳极薄膜

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Research progress of catalysts for direct coal liquefaction

引用

Journal of Energy Chemistry 2025年第1期 481-497页

作者： Wei Song Penggao Liu Xinyue Chen Ting Wang Chunrong He Rui Hao Kaiyu Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University college of Chemistry and chemical Engineering Henan Polytechnic University hunan Provincial Key Laboratory of chemical Power Sources College of Chemistry and Chemical Engineering Central South University

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Hybrid Ti_2AlC Bonded Diamond Composites Prepared by a Self-propagation Sintering Approach

引用

Journal of Wuhan University of technology(Materials Science) 2019年第1期34卷 82-85页

作者： ZHANG Wangxi LIANG Baoyan LUO Wei WANG Yanzhi School of Materials and chemical Engineering Zhongyuan University of Technology Department of chemical Engineering Sichuan Vocational College of Chemical Technology

Ti, Al, graphite and diamond powders were used as raw materials to prepare Ti_2AlC matrixbonded diamond composite using self-propagating high-temperature synthesis(SHS) method. The effect of diamond size and content on the fabrication of Ti_2AlC-bonded diamond material was investigated. Results showed that Ti_2AlC matrix-bonded diamond composites could be obtained by SHS. The phase composition and microstructure of the Ti_2AlC-bonded diamond material were influenced by the diamond content and size. When the diamond(93 μm) additive amounts were 10% and 20%, the product phases included Ti_2AlC, TiC and Al_3Ti. However, excess Ti and Al persisted in the sample that contained 30% diamond. Diamond bonded well with the matrix in the sample that contained 10% diamond. Moreover, addition of coarse diamond particles with sizes of 93 and 125 μm produced a mainly Ti_2AlC matrix. However, diamond adequately reacted with Ti to form TiC when finer diamond particles(5 and 10 μm) were used.

关键词： titanium aluminum carbide diamond content size self-propagation high temperature sintering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tricolor emitting and energy transfer in the phosphor Ba_2ZnSi_2O_7:Ce^(3+),Eu^(3+),Eu^(2+) for white-LED based near-UV chips

引用

Journal of Rare Earths 2015年第5期33卷 463-468页

作者：邓升智邱忠贤张茂美周文理张吉林李承志荣春英余丽萍廉世勋 Key Laboratory of chemical Biology & Traditional Chinese Medicine Research (Ministry of Education) Key Laboratory of Sustainable Resources Pro-cessing and Advanced Materials of hunan Province college college of Chemistry and chemical Engineering hunan Normal University Changde vocational Technical college

The red, green and blue （R/G/B） tricolor emitting phosphors Ba2ZnSi2O7 co-doped with Ce3＋and Eu3＋were synthesized in air atmosphere by a conventional high temperature solid-state reaction technique. All of the excitation spectrum of the phosphor Ba2ZnSi2O7：Ce,Eu showed a strong broad band absorption in the n-UV region whenever monitored by red （630 nm）-emitting or by green （500 nm）-and blue （402 nm）-emitting. Under the excitation of 330 nm, the emission spectrum containing a blue-violet emis-sion band, a green emission and four sharp lines originated from the characteristic transitions of Ce3＋, Eu2＋and Eu3＋ions, of which the relative intensities of the three emission bands could be controlled by the doping concentration of Ce3＋. The ca. CIE chromaticity co-ordinates （x=0.317, y=0.309） of the phosphor Ba1.94ZnSi2O7：0.03Eu,0.01Ce was very close to the standard white （x=0.33, y=0.33）, which suggested that it was a novel single-phased white-light emitting phosphor for LED-based near-UV chip. The mechanisms of energy transfer from Eu2＋to Eu3＋via Ce3＋was also discussed.

关键词： rare earths Ba2ZnSi2O7:Eu,Ce R/G/B tricolor emitting phosphor white-LEDs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

One-step pickling-activation before magnesium alloy plating

引用

中国有色金属学会会刊：英文版 2009年第2期19卷 504-510页

作者：王新娟余刚欧阳越军何晓梅张俊叶立元 State Key Laboratory of Chemo/Bisensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University Department of Chemistry and chemical Engineering Huaihua College Department of Chemistry and chemical Engineering Hunan Institute of Technology

A one-step pickling-activation process was proposed as an environmental friendly pretreatment method in phosphate-permanganate solution before electroplating on magnesium alloys. The effects of pickling-activation on qualities of coating were assessed by adhesion and porosity testing of copper plating. The interfacial reactions between specimen and solution were analyzed with SEM,EDX and XRD. The results show that the developed process of pickling-activation can equalize the potentials on substrate surface. The compacted zinc film can be obtained by zinc immersion after treating magnesium alloy in the pH 4-6 phosphate-permanganate solution for 3-5 min. The adhesion and corrosion resistance of copper plating are enhanced. The one-step pickling-activation can replace the existing two-step process of acid pickling and activation which contains a great deal of chromium and fluorine. The procedure of surface pretreatment is simplified and the production environment is improved.

关键词：激活过程合金电镀镁合金酸洗高锰酸钾溶液预处理方法 X射线衍射表面预处理

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：