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Rare Metals 2006年第z2期25卷 146-149页

作者： CHEN Ling han jing YU Shengxue Department of Applied Chemistry Yanshan University Qinhuangdao 066004 China Department of Applied Chemistry Yanshan University Qinhuangdao 066004 China Department of Applied Chemistry Yanshan University Qinhuangdao 066004 China

In order to prepare ornamental and anti-corrosive coating on aluminum alloys, preparation technology of black micro-arc ceramic coatings on Al alloys in silicate based electrolyte was studied. The influence of content of Na2WO4 and combination additive in solution on the performance of black ceramic coatings was studied; the anticorrosion performances of black ceramic coatings were evaluated through whole-immersion test and electrochemical method in 3.5% NaCl solution at different pH value; SEM and XRD were used to analyze the surface morphology and phase constitutes of the black ceramic coatings. Experimental results indicated that, without combination additives, with the increasing of Na2WO4 content in the electrolyte, ceramic coating became darker and thicker, but the color was not black; after adding combination additive, the coating turned to be black; the black ceramic coating was multi-hole form in surface. There was a small quantity of tungsten existing in the black ceramic coating beside α-Al2O3 phase and β-Al2O3 phase. And aluminum alloy with black ceramic coating exhibited excellent anti-corrosion property in acid, basic and neutral 3.5% NaCl solution.

关键词： aluminum alloy micro-arc oxidation black coating anti-corrosion performance

Em Algorithm of the Truncated Multinormal Distribution with Linear Restriction on the Variables

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 155-162页

作者： Bai-suo JIN jing-jing han Shu DING Bai-qi MIAO Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Nanjing Research Institute of Electronics Technology Nanjing 210039 China School of Economics Hefei University of Technology Hefei 230009 China

A new expectation-maximization（EM） algorithm is proposed to estimate the parameters of the truncated multinormal distribution with linear restriction on the variables. Compared with the generalized method of moments（GMM） estimation and the maximum likelihood estimation（MLE） for the truncated multivariate normal distribution, the EM algorithm features in fast calculation and high accuracy which are shown in the simulation results. For the real data of the national college entrance exams（NCEE）, we estimate the distribution of the NCEE examinees＇ scores in Anhui, 2003, who were admitted to the university of science and technology of China（USTC）. Based on our analysis, we have also given the ratio truncated by the NCEE admission line of USTC in Anhui, 2003.

关键词： EM algorithm truncated multinormal distribution linear restriction national college entrance exams

Test research on sticking mechanism during hot rolling of SUS 430 ferritic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 573-578页

作者： Jun-xian Liu Yong-jun Zhang jing-tao han School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The sticking phenomenon during hot rolling of SUS 430 ferritic stainless steel was investigated by means of a two-disc type high-temperature wear tester. The test results indicate that sticking particles on the surfaces of high chromium steel （HiCr） and high-speed steel （HSS） rolls undergo nucleation, growth, and saturation stages. Grooves on the roll surface generated by grinding provide nucleation sites for sticking particles. The number of sticking particles on the HiCr roll surface is greater than that on the HSS roll surface. The average surface roughnesses （Ra） of HiCr and HSS rolls change from 0.502 and 0.493 μm at the initial stage to 0.837 and 0.530 μm at the saturation stage, respectively. The test further proves that the sticking behavior is strongly dependent on roll materials, and the HSS roll is more benefi- cial to prevent particles sticking compared with the HiCr roll under the same hot-rolling conditions.

关键词： ferritic steel stainless steel hot rolling sticking rolls

FUNCTIONAL MAGNETIC RESONANCE IMAGING STUDY OF THE BRAIN IN PATIENTS WITH AMYOTROPHIC LATERAL SCLEROSIS

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Chinese Medical Sciences Journal 2006年第4期21卷 228-233页

作者： jing han Lin Ma Department of Neuroradiology Huanhu Hospital Tianjin 300060 Department of Radiology General Hospital of People＇s Liberation Army Beijing 100853

Objective To study the activation changes of the brain in patients with amyotrophic lateral sclerosis （ALS） while executing sequential finger tapping movement using the method of blood oxygenation level dependent （BOLD） functional magnetic resonance imaging （tMRI）. Methods Fifteen patients with definite or probable ALS and fifteen age and gender matched normal controls were enrolled. MRI was performed on a 3.0 Tesla scanner with standard headcoiL The functional images were acquired using a gradient echo single shot echo planar imaging （EPI） sequence. All patients and normal subjects executed sequential finger tapping movement at the frequency of 1-2 Hz during a block-design motor task. Structural MRI was acquired using a three-dimensional fast spoiled gradient echo （3D-FSPGR） sequence. The tMRI data were analyzed by statistical parametric mapping （SPM）. Results Bilateral primary sensorimotor cortex （ PSM）, bilateral premotor area （ PA）, bilateral supplementary motor area （SMA）, bilateral parietal region （ PAR）, contralateral inferior lateral premotor area （ ILPA）, and ipsilateral cerebellum showed activation in both ALS patients and normal controls when executing the same motor task. The activation areas in bilateral PSM, bilateral PA, bilateral SMA, and ipsilateral cerebellum were significantly larger in ALS patients than those in normal controls （ P 〈 0.05 ）. Extra activation areas including ipsilateral ILPA, bilateral posterior limb of internal capsule, and contralateral cerebellum were only detected in ALS patients. Conclusions Similar activation areas are activated in ALS patients and normal subjects while executing the same motor task. The increased activation areas in ALS patients may represent neural reorganization, while the extra activation areas in ALS patients may indicate functional compensation.

关键词： amyotrophic lateral sclerosis blood oxygenation level dependent functional compensation neural reorganization

Investigating core axial power distribution with multiconcentration gadolinium in PWR

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Nuclear Science and Techniques 2022年第11期33卷 22-32页

作者： jing-Gang Li jing-han Peng Chao Wang Jun Chen Fei Xu Yun-Fan Ma China Nuclear Power Technology Research Institute Shenzhen 518000China

Core axial power distribution is an essential topic in pressurized water reactor(PWR)reactivity *** PWRs limit stability against axial core power oscillations at a high-cycle *** the‘‘camel’’peak power shape typically occurs with increasing depletion,the approaches used for the axial power control deserve special *** study aims to investigate the performance of different gadolinium rod design schemes in core axial power control during power operation based on the reactivity balance strategy,and to propose new multiconcentration gadolinium rod design *** the new design schemes,low-concentration gadolinium pellets are filled in the axial hump part of the gadolinium rod,and high-concentration gadolinium pellets are filled in the other *** impact of different gadolinium rod design schemes on the main core characteristics was evaluated using the nuclear design code package PCM developed by *** results show that the new gadolinium rod design significantly impacts the core axial power *** new design schemes can efficiently improve the core axial power distribution along the entire cycle by reducing the core axial power peak at the end of a cycle,enhancing the reactor operation stability,and achieving a better core safety margin,revealing a sizeable potential application.

关键词： Gadolinium PCM software package Fuel assembly Core axial power distribution Reactivity

Restoring ancient civilizations with “Herit-Materials”:Technological advances in its studies

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Science China(Technological Sciences) 2023年第7期66卷 1952-1974页

作者： MA Xiao LI WeiDong han jing HUANG Xiao LUO HongJie Institute for the Conservation of Cultural Heritage School of Cultural Heritage and Information ManagementShanghai UniversityShanghai 200444China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China

Cultural relics are man-made objects left from ancient times,with historical,artistic,and scientific ***-interdisciplinary research of cultural relics would enable people to obtain a variety of information associated with them,from which the restoration of ancient civilization was *** to natural weathering,many cultural relics are in a fragile state,and conservation treatments that can prolong their lifetime are important,which may involve the use of conservation *** this paper,we define the new term “Herit-Materials” as two types of materials,including ancient cultural relics themselves and novel functional materials for conservation *** the first type of Herit-Materials-cultural relics themselves,as one type of ancient materials,the concept of the relationship between the structure,composition,performance,and technology of them was *** research paradigm for ancient cultural relics is also *** such a paradigm,the way how analysis and research were performed on ancient cultural relics are illustrated in detail with examples of ancient ceramics and textile ***,as the second type of Herit-Materials,three categories of conservation materials,such as emergent conservation materials on archaeological sites,consolidation materials,and cleaning materials were reviewed in detail,including basic concepts,criteria for choosing appropriate materials for conservation purposes,evaluation of the conservation effects after application,along with the application methods of those conservation ***,as Herit-Materials’ studies have attracted more and more researchers and have also created new inter-disciplinary research fields,the following research directions are recommended for scholars who have an interest,including the development of the advanced and comprehensive analytical technique of Herit-Materials,non-destructive and in-situ characterization & testing of Herit-Materials,the database of comp

关键词： cultural relics conservation materials Herit-Materials ancient civilization menthol ancient ceramics

Balanced strength and ductility by asymmetric gradient nanostructure in AZ91 Mg alloy

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Journal of Materials Science & Technology 2024年第17期184卷 167-179页

作者： Bingqian Xu Jiapeng Sun Lingling Wang jing han Guosong Wu College of Mechanics and Materials Hohai UniversityNanjing 211100China School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116China

High-strength Mg alloys have historically suffered from a challenge in achieving good ***,we report an asymmetric gradient nanostructure design prepared by ultrasonic severe surface rolling(USSR)at room *** conventional gradient-nanostructured materials that employ a hard-soft-hard sandwich structure,this new design incorporates a combined gradient distribution of grain microstructure and nanoprecipitates throughout the entire sample along the thickness *** nanoprecipitates are identified as theβ-Mg_(17)Al_(12)phase and are primarily generated through In-situ pre-cipitation promoted by the USSR-induced high-density dislocations and temperature ***-ing from this unique microstructure,an outstanding strength-ductility synergy is achieved,with a yield strength of 372.8 MPa,an ultimate tensile strength of 453.3 MPa,and an elongation of 11.5%.The en-hanced strength can be attributed to several mechanisms,including grain boundary strengthening,dislocation strengthening,precipitation strengthening,twin strengthening,and hetero-deformation induced(HDI)*** HDI hardening and activation of multiple deformation modes also contribute to good *** work provides a promising and effective method for overcoming the longstanding strength-ductility trade-offdilemma in Mg alloys.

关键词： Mg alloy Strength-ductility synergy Gradient nanostructure Precipitates AZ91

Recent Research Progress of Paper-Based Supercapacitors Based on Cellulose

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Energy & Environmental Materials 2024年第3期7卷 345-373页

作者： Chuanyin Xiong Tianxu Wang jing han zhao Zhang Yonghao Ni College of Bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Materials Science and Engineering Tianjin Polytechnic UniversityTianjin 300387China Department of Chemical and Biomedical Engineering The University of MaineOronoMaine 04469USA University of New Brunswick Limerick Pulp&Paper CtrFredericton New Brunswick E3B 5A3Canada

In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good *** an important energy storage device,paper-based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent *** present,researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage *** development of paper-based supercapacitors provides an important direction for the development of green and sustainable ***,it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and *** this review,the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites,preparation skills,and electrochemical ***,some opinions on the problems in the development of this field and the future development trend were *** is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.

关键词： cellulose electrochemical performance flexibility paper-based supercapacitor porous

Titanium effect on the microstructure and properties of laminated high boron steel plates

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 492-499页

作者： Lin-lin Yuan jing-tao han jing Liu Dong-bin Wei Mehari Zelalem Abathun School of Materials Science and Engineering University of Science and Technology Beijing School of Electrical Mechanical and Mechatronic Systems University of TechnologySydney

High-boron steel is an important material used for thermal neutron shielding. The appropriate amount of added boron must be de- termined because excessive boron may deteriorate the steel＇s workability. A uniform microstructure can be formed by adding titanium to boron steel. In this study, casting and hot rolling were used to fabricate laminated high-boron steel plates whose cores contained 2.25wt% boron and 0wt%-7.9wt% titanium. The effects of titanium content and hot-rolling and heat-treatment processes on the microstructure and properties of the laminated plates were studied. The results indicated that the optimum titanium content was 5.7wt% when the boron content was 2.25wt%, and that the best overall properties were obtained after heat treatment at 1100℃ for 4 h. The tensile strength, yield strength, and elongation at the specified temperature and holding time were as high as 526.88 MPa, 219.36 MPa, and 29%, respectively.

关键词： boron steel laminated materials titanium boride hot rolling heat treatment

Applications of transition-metal sulfides in the cathodes of lithium-sulfur batteries

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Tungsten 2020年第2期2卷 134-146页

作者： jing‑han Zuo Yong‑Ji Gong School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Lithium-sulfur(Li-S)batteries are considered as one of the most promising candidates for next-generation energy storage systems with high energy density and reliable ***,the commercial applications of lithium-sulfur batteries is hindered by several shortcomings like the poor conductivity of sulfur and its reaction products,and the loss of active materials owing to the diffusion of lithium polysulfides(LiPSs)into the ***,the effective restraining of the LiPSs and the promotion of the sluggish conversion are highly demanded to fulfill the potential of lithium-sulfur ***,we summarize the applications of transition-metal sulfides(TMSs)in the cathodes over recent years and demonstrate the unique advantages they possess to realize reliable long-life lithium-sulfur batteries.

关键词： Lithium–sulfur battery Transition metal sulfides Polysulfide adsorption Electrode conductivity Electrocatalysis