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Microstructure and mechanical properties of in situ(Ti,Nb)C_p/Fe-based laser composite coating prepared with different heat inputs

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Rare Metals 2018年第10期37卷 852-858页

作者： qing-tang li Yong-Ping Lei Han-Guang Fu Zhong-Wei Wu Jian lin School of Materials Science and Engineering Beijing University of Technology

In this paper, in situ （Ti, Nb）C particle （（Ti, Nb）Cp） reinforced Fe-based composite coatings were produced by laser cladding on the surface of the high carbon steel. The effects of heat input on the microstructure, distribution characteristics of particle, and mechanical properties of the coating were investigated. The results show that （Ti, Nb）C multiple carbide particle is synthesized during solidification of molten pool. The size of particle coarsens gradually, the area ratio of particle increases, and the amount of particles presents a non-monotonous variation with the increase in energy density. The mechanical properties of the coating are improved dramatically compared with those of the substrate, benefiting from its higher hardness and dispersed in situ （Ti, Nb）Cp in it. With the change in heat input, the mechanical performances of the coating vary except the hardness. When energy density is 1 × 10^5 ***-2, tensile strength and wear resistance of the coating achieve optimal value due to moderate content and size of the particle in the coating.

关键词： Laser parameters (Ti, Nb)C particle Distribution characteristic Laser coating Mechanical property

Distribution Characteristics and Reinforcing Behavior of(Ti,Nb)C Reinforced Particle in the Coating Fabricated by Laser Rapid Cladding

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Journal of Iron and Steel Research International 2016年第2期23卷 124-129页

作者： qing tang li Yong ping LEI Han-guang FU Zhong-wei WU Jian liN School of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

（Ti, Nb）C reinforced Fe based laser coatings were prepared with normal and high scanning velocities of the laser beam. The distribution characteristics of reinforced particles in the coatings were investigated. The mechanical properties of coatings were tested. The results showed that the morphologies of the microstructure and the reinforced particle changed dramatically at high solidification rate due to rapid laser processing compared with that prepared by normal processing. Two kinds of particles were observed in the coating. One was （Ti, Nb）C multiple carbide particle with the size of micron and sub micron scales, in which a mass of dislocations were found. Another was nano sized particle including a Fe and （Ti, Nb）C obtained by rapid solidification. The microstructure of the coatings was highly refined and a large number of twin crystals were found in matrix. The resuhs of mechanical properties test revealed that the wear resistance of the coaling was improved by rapid laser processing, compared with that of the coating prepared with normal speeds. The ahove-mentioned conclusion indicated that rapid laser cladding can promote not on ly the processing efficiency but also lhe mechanical properties of the coating.

关键词： laser rapid cladding wear resistant coating (Ti,Nb)C particle formation mechanism mechanical property

A Comparison of the Biological Characteristics of EV71 C4 Subtypes from Different Epidemic Strains

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Virologica Sinica 2010年第2期25卷 98-106页

作者： li-chun WANG Song-qing tang Yan-mei li Hong-lin ZHAO Cheng-hong DONG Ping-fang CUI Shao-hui MA Yun liAO Long-ding liU Qi-han li Institute of Medical Biology Chinese Academy of Medical Sciences Peking Union Medical College Kunming 650118 China

The comparative analysis of the biological characterization and the genetic background study of EV71 circulating strains is commonly recognized as basic work necessary for development of an effective EV71 vaccine. In this study, we sequenced five EV71 circulating strains, isolated from Fuyang, Hefei, Kunming and Shenzhen city of China and named them FY-23, FY-22, H44, K9 and S1 respectively. The sequence alignment demonstrated their genotypes be C4. The genetic distance of the VP1 gene from these isolates suggested that they were highly co-related with genetic identity similar to other previously reported EV71 strains in China. Additionally, these strains were identified to display some obvious proliferation dynamics and plaque morphology when propagated in Vero cells. However, a distinctive difference in pathogenic ability in neonatal mice was found. Some differences in cross neutralization test & immunogenic analysis were also found. All these results are related to the biological characterization of circulating EV71 strains in China and aid in the development of an EV71 vaccine in the future.

关键词： Enterovirus 71 (EV71) Subtype C4 Epidemic strain Hand-foot and mouth disease (HFMD)

Optimization of clear liquid fermentation condition for ethanol production from Canna edulis Kerl

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Natural Science 2010年第2期2卷 115-119页

作者： Ying Shen qing-li tang Tian-Xiang Wu 不详

In this paper, clear liquid fermentation condition for ethanol production from Canna edulis Kerl with orthogonal design was studied. We have studied five factors that influenced clear liquid fermentation condition for ethanol production from Canna edulis Kerl by the single-factor test. The five factors were α-amylase amount, glu-coamylase amount, pH, nitrogen and auxiliary materials amount. Selected the best amounts of α-amylase, glucoamylase, pH, nitrogen source and auxiliary materials by means of the singe- factors test. And then, we used the Orthogonal test to optimize the fermentation process. The study showed that the best fermentation condi-tions were α-amylase amount 7 u/g ***, glu-coamylase amount 145u/g C. edulis, pH 4.4 and the amount of urea 0.08%, 1% of rice bran as auxiliary materials. The rate of alcohol which was produced by the best fermentation conditions is 21.5% that increased by 1.3% than the rate of alcohol by the single-factor test.

关键词： Alcohol Canna edulis Kerl Clear liquid Fermentation Orthogonal Design

Influence of the femoral head size on early postoperative gait restoration after total hip arthroplasty

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Chinese Medical Journal 2009年第13期122卷 1513-1516页

作者： ZHOU Yi-xin GUO Sheng-jie liU qing tang Jing li Yu-jun Department of Orthopaedic Surgery Beijing Jishuitan Hospital Fourth Clinical College of Peking University Beijing 100035 China

Background We investigated the effects of using large-diameter femoral heads in total hip prostheses on early postoperative gait restoration in patients undergoing total hip arthroplasty （THA）. Methods We collected data for 19 primary THAs using 28-mm metal-on-polyethylene heads （conventional group） and for 12 THAs （BHR group） using metal-on-metal femoral heads with an average size of 45 mm （range, 40-49mm）. All patients had unilateral femoral head avascular necrosis. All patients underwent Harris Hip Scores evaluation and gait analysis with the IDEEA device at the same 3 time points which were before surgery and then at 1 month and again at 3 months after surgery, and the parameters measured were walking speed, stride length （SL）, single limb support （SLS）, cycle duration （CD）, and swing power （SP）. Harris Hip Scores and gait analysis parameters for both groups were compared. Results Intraclass comparison indicated that Harris Hip Scores, speed scores, and gait parameter measures in both groups improved significantly with the passage of time; Interclass comparison showed no significance between Harristm postop - HarriSpreop and Harris3m postop- HarriSpreop in both groups. The speed in the BHR group at 1 month and at 3 months after surgery was significantly higher than that of conventional group. At 1 month after surgery, each mean for SLnormal - SLaffected, （SLSnormal - SLSaffected）/CD, and SPnormal - SPaffected in the BHR group was significantly lower than that for the conventional group. At 3 months after surgery, the differences between means for both groups for SLnormal - SLaffected, （SLSnormal- SLSaffected）/CD, and SPnormal - SPaffected were not significant, but the mean of SPnorrnal - SPaffected in the BHR group was significantly lower than that in the conventional group. Conclusions Our data suggest that large-diameter femoral heads in THA provide better early gait restoration than conventional-size femoral heads.

关键词： total hip arthroplasty femoral head size Harris Hip Score gait analysis

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内地与澳门缓刑立法比较研究

西南民族大学学报（人文社会科学版） 2009年第10期30卷 167-170页

作者：唐青利四川师范大学学生工作部

缓刑制度,在我国内地和澳门的刑法中均有规定,相较而言,殊同各有。本文对两地现行刑法中的缓刑制度,在适用条件、暂缓执行期限、缓刑执行、缓刑法律后果等方面作了粗略比较,客观评析了两地立法的优劣得失,以期能促进内地缓刑立法的完善。

关键词：缓刑内地澳门比较

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： li Xu Huiming Xu Changyong tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

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亲属在刑法上帮助退赔财产的法律制度研究

四川师范大学学报（社会科学版） 2009年第1期36卷 85-88页

作者：唐青利四川师范大学学生工作部成都610068

在目前的司法实践中,存在着大量亲属用自己的合法财产帮助犯罪人退还违法所得的现象;但是,由于这种现象没有相关法律的系统规范,在实际操作中伤害了亲属的善良感情也对执法机关造成了不好的影响。从亲属帮助罪犯退赔财产行为的立法现状... 详细信息

在目前的司法实践中,存在着大量亲属用自己的合法财产帮助犯罪人退还违法所得的现象;但是,由于这种现象没有相关法律的系统规范,在实际操作中伤害了亲属的善良感情也对执法机关造成了不好的影响。从亲属帮助罪犯退赔财产行为的立法现状、执法现状及该行为的性质来看,我国有必要建立"亲属在刑法上帮助退赔财产"的法律机制。

关键词：追缴责令退赔赃款赃物亲属

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing Shi Guofan Zhang Yuxuan Zhu Binbin li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation