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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1273-1282页

作者： Hang Zhao Jian-jun Li Zhi-zhen Zheng Ai-hua wang Qi-wen Huang da-wen Zeng State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology

In this work, an in situ synthesized TiC-reinforced metal matrix composite （MMC） coating of approximately 350-400μm thickness was fabricated on a gray cast iron （GCI） substrate by plasma transferred arc （PTA） surface alloying of Ti-Fe alloy powder. Microhard- ness tests showed that the surface hardness increased approximately four-fold after the alloying treatment. The microstructure of the MMC coating was mainly composed of residual austenite, acicular martensite, and eutectic ledeburite. Scanning electron microscopy （SEM） and X-ray diffraction analyzes revealed that the in situ TiC particles, which were formed by direct reaction of Ti with carbon originally contained in the GCI, was uniformly distributed at the boundary of residual anstenite in the alloying zone. Pin-on-disc high-temperature wear tests were performed on samples both with and without the MMC coating at room temperature and at elevated temperatures （473 K and 623 K）, and the wear behavior and mechanism were investigated. The results showed that, after the PTA alloying treatment, the wear resistance of the sam- ples improved significantly. On the basis of our analysis of the composite coatings by optical microscopy, SEM with energy-dispersive X-ray spectroscopy, and microhardness measurements, we attributed this improvement of wear resistance to the transformation of the microstruc- ture and to the presence of TiC particles.

关键词： gray cast iron composite coatings particle-reinforced composites titanium carbide surface alloying microstructure wear

Group-blind multi-user detection under multi-path channel

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 45-51页

作者： wang Dong-yu LIU wen-kai YANG Jun YANG da-cheng Department of Electronic Engineering North China University of Technology Beijing 100041 China School of Computer Science and Technology Beijing University of Posts and Telecommunications Beijing 100876 China School of Communication and Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes an improved generalized side-lobe canceller （GSC） receiver structure based on a new group constraint, which is suitable to eliminate multiple-access interference （MAI）, inter-symbol interference （ISI） in direct-sequence code-division multiple access （DS/CDMA） downlink multi-user system. The new group constraint is deduced to construct the group-blind adaptive multi-user detector. The analysis indicates that the improved GSC under the new constraint not only retains the property of suppressing ISI and canceling MAI, but also can extract useful information from the succeeding bit for the desired user. The simulations show that the improved GSC filter can cancel the MAI efficiently whether the wireless channel length is short or long,

关键词： group-blind detection GSC constraint ISI MAI

Adaptive STBC-VBLAST transmission for mobile WiMAX

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 38-42页

作者： JIN Jing wang Fei YANG Hong-wen YANG da-cheng School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Multiple-input multiple-output（MIMO） technology can provide high data rate and substantial *** time block code（STBC） provides diversity gain and obtains signal of better quality even under bad channel ***,it has no contribution to system average ***-bell laboratory layered space-time（VBLAST） improves peak data rate but leads to higher packet error rate（PER） at cell edge when the channel condition is *** get both higher system average throughput and cell edge throughput,an adaptive STBC-VBLAST transmission for downlink mobile WiMAX system is proposed and analyzed through system-level simulation in this *** proposed approach compares the effective capacity of two candidate MIMO modes（STBC or VBLAST） and reports its decision to the base station with only one extra signaling *** simulation results show that the proposed approach can attain a balance between STBC and ***,the cell throughput approximates that of pure VBLAST and the cell edge throughput is close to that of pure STBC.

关键词： mobile WiMAX MIMO STBC VBLAST adaptive STBC-VBLAST transmission

A drawstring triboelectric nanogenerator with modular electrodes for harvesting wave energy

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Nano Research 2023年第8期16卷 10931-10937页

作者： da Zhao Hengyu Li Jianlong wang Qi Gao Yang Yu Jianming wen Zhong Lin wang Tinghai Cheng School of Mechatronic Engineering Changchun University of TechnologyChangchun 130012China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China College of Engineering Zhejiang Normal UniversityJinhua 321004China Georgia Institute of Technology AtlantaGA 30332-0245USA

The development and utilization of marine blue energy has become the focus of current research.A drawstring triboelectric nanogenerator with modular electrodes(DS-TENG)is proposed to harvest wave *** displacement and water wave adaptability are improved by using the drawstring structure in the ***,the modular electrode design is applied to improve the durability and replaceability of the generation *** rationality of the structure is verified by theoretical analysis,and performance experiments on the fundamental output,displacement and frequency,durability and application are carried *** DS-TENG can achieve output performance of 98.03 nC,3.63μA,238.50 V and 923.92µW at 150 mm and 1.0 *** addition,the performance drops by 6.11%after 110,000 cycles for DS-TENG *** paper will provide reference for the design of TENG that adapts to a wide range of wave heights.

关键词： triboelectric nanogenerator wave energy harvesting drawstring modular electrodes motion displacement

Stress release in high-capacity flexible lithium-ion batteries through nested wrinkle texturing of graphene

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Journal of Energy Chemistry 2021年第10期30卷 243-249,I0008页

作者： Jing Chen Lei wen Ruopian Fang da-Wei wang Hui-Ming Cheng Feng Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026.AnhuiChina School of Chemical Engineering The University of New South WalesSydney 2052Australia Tsinghua-Berkeley Shenzhen Institute Tsinghua UniversityShenzhen 518055GuangdongChina

Flexible lithium-ion batteries(LIBs)are critical for the development of next-generation smart *** reaction-based electrodes have been considered promising to construct high energy-density flexible LIBs,which satisfy the ever-increasing demand for practical ***,these electrodes suffer from inferior lithium-storage performance and structural instability during deformation and long-term lithiation/*** are caused by the sluggish reaction kinetics of active-materials and the superposition of responsive strains originating from the large lithiation-induced stress and applied ***,we propose a stress-release strategy through elastic responses of nested wrinkle texturing of graphene,to achieve high deformability while maintaining structural integrity upon prolonged cycles within high-capacity *** wrinkles endow the electrode with a robust and flexible network for effective stress *** resulting electrode shows large reversible stretchability,along with excellent electrochemical performance including high specific capacity,high-rate capability and long-term cycling *** strategy offers a new way to obtain high-performance flexible electrodes and can be extended to other energy-storage devices.

关键词： Wrinkling graphene Structural design Stress release High-capacity active material Flexible electrodes

A Heuristic Sampling Method for Maintaining the Probability Distribution

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Journal of Computer Science & Technology 2021年第4期36卷 896-909页

作者： Jiao-Yun Yang Jun-da wang Yi-Fang Zhang wen-Juan Cheng Lian Li Key Laboratory of Knowledge Engineering with Big data of Ministry of Education Hefei University of Technology Hefei 230601China National Smart EldeTca/re International Science and Technology Coopemtion Base Hefei University of Technology Hefei 230601China School of Computer Science and Information Engirwering Hefei University of TechnologyHefei 230601China School of Mathematics Hefei University of TechnologyHefei 230601China

Sampling is a fundamental method for generating data *** many data analysis methods are developed based on probability distributions,maintaining distributions when sampling can help to ensure good data analysis ***,sampling a minimum subset while maintaining probability distributions is still a *** this paper,we decompose a joint probability distribution into a product of conditional probabilities based on Bayesian networks and use the chi-square test to formulate a sampling problem that requires that the sampled subset pass the distribution test to ensure the ***,a heuristic sampling algorithm is proposed to generate the required subset by designing two scoring functions:one based on the chi-square test and the other based on likelihood *** on four types of datasets with a size of 60000 show that when the significant difference level,a,is set to 0.05,the algorithm can exclude 99.9%,99.0%,93.1%and 96.7%of the samples based on their Bayesian networks-ASIA,ALARM,HEPAR2,and ANDES,*** subsets of the same size are sampled,the subset generated by our algorithm passes all the distribution tests and the average distribution difference is approximately 0.03;by contrast,the subsets generated by random sampling pass only 83.8%of the tests,and the average distribution difference is approximately 0.24.

关键词： Bayesian network chi-square test sampling probability distribution

PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong Liu Xiaolin Li Xiaowei Zhou Wei Chen Aidong wen Minna Liu Yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

Performance analysis of amplify-and-forward relaying with hybrid-ARQ in Rayleigh fading channels

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 32-37页

作者： ZHENG Kan HU Li-jie GU da-qing wang Hai-la wang wen-bo Wireless Signal Processing and Network Lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Orange R&D (Beijing) Beijing 100080 China

Hybrid automatic repeat request（HARQ） is a well-known technique for improving system throughput and link performance of wireless communication systems,including cooperative communication *** amplify-and-forward（AF） relaying method is one of the most attractive cooperative diversity schemes because of its low *** this article,the end-to-end performance in terms of block error rate（BLER） and normalized throughput of AF relaying with HARQ transmission under the Rayleigh fading channel is *** results validate the proposed analysis and demonstrate the gain of HARQ schemes in AF relaying *** analytical method can be extended to the systems with other HARQ protocols and other cooperative relaying schemes.

关键词： cooperative diversity AF HARQ BLER

Decolorization of reactive brilliant red K-2BP by white rot fungus under sterile and non-sterile conditions

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Journal of Environmental Sciences 2006年第3期18卷 428-432页

作者： GAO da-wen wen Xiang-hua QIAN Yi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environment Science and Engineering TsinghuaUniversity Beijing 100084 China.

Almost all the studies both domestic and international using white rot fungus for dye wastewater treatment are performed under sterile conditions. However, it is obviously unpractical that wastewater with dyes is treated under sterile conditions. A feasible study was made for using white rot fungus Phanerochaete chrysosporium to degrade reactive brilliant red K-2BP dye under non-sterile conditions. The results showed that there was no decolorizing effect under non-sterile condition if white rot fungus was incubated under non-sterile condition, and the decolorization was always near to 0% during decolorizing test for 3 d; in the meantime, a lot of yeast funguses were found in liquid medium when white rot fungus was incubated under non-sterile conditions; however, if white rot fungus was incubated under sterile condition firstly, its decolorization was above 90% under non-sterile condition, which was similar to that of sterile condition. So we point out that the treating process for wastewater with dyes should be divided into two stages. The first stage is that white rot fungus should be incubated under sterile conditions, and the second stage is that reactive brilliant red K-2BP is decolorized under non-sterile conditions. The method not only save the operation cost which decolorizing reactive brilliant red K-2BP under sterile condition, but also provide the feasibility for using white rot fungus to degrade wastewater with dyes under non-sterile conditions.

关键词： white rot fungus Phanerochaete chrysosporium reactive brilliant red K-2BP decolorization non-sterile condition

基于地理分区的陕北黄土高原生态系统服务权衡/协同的尺度效应研究

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水土保持研究 2025年第1期32卷 305-315页

作者：温昕王继军韩晓佳中国科学院水土保持与生态环境研究中心中国科学院水利部水土保持研究所中国科学院大学西北农林科技大学水土保持研究所中国科学院生态环境研究中心

[目的]明晰生态系统服务的权衡/协同关系，保证生态系统服务长期有效供应，实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例，利用1990—2020年土地利用变化数据，基于InVEST模型量化4种关键生态系统服务即碳储量、... 详细信息

[目的]明晰生态系统服务的权衡/协同关系，保证生态系统服务长期有效供应，实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例，利用1990—2020年土地利用变化数据，基于InVEST模型量化4种关键生态系统服务即碳储量、产水量、土壤保持量和生境质量的时空分布特征，通过相关性分析探讨了各类生态系统服务间的权衡/协同关系和呈现的尺度特征。[结果](1) 1990—2020年碳储量和生境质量处于不断增加的趋势，产水量和土壤保持量呈现先降低后增加总体增加的趋势，空间上呈东南略低西北略高的分布。(2)陕北黄土高原生态系统服务以协同作用为主，且在1990—2020年协同效应不断增强，权衡作用主要发生在产水量与其他生态系统服务之间，权衡作用的区域主要分布在研究区西部和东北部地区。(3)生态系统服务间的权衡/协同作用存在着空间尺度效应，随着空间尺度的增加，相关性逐渐增强而显著性有所下降，且作用关系的方向性会发生改变。[结论]陕北黄土高原生态系统服务以协同为主，生态系统服务间的权衡/协同作用存在着空间尺度效应。

关键词：生态系统服务权衡/协同作用尺度效应地理分区陕北黄土高原