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Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

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China Communications 2024年第6期21卷 23-39页

作者： jiang Jie Lyu Bin Chen Pengcheng Yang zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemical Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding Kun Zhao Shican jiang zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) *** findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关键词： Chemical-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites

A state-of-the-art review of the development of self-healing concrete for resilient infrastructure

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 151-169页

作者： Dong LU Xi jiang Yao ZHANG Shaowei ZHANG Guoyang LU zhen LENG Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The brittleness of cement composites makes cracks almost inevitable,producing a serious limitation on the lifespan,resilience,and safety of concrete *** address this brittleness,self-healing concrete has been developed for regaining its mechanical and durability properties after becoming cracked,thereby promising sustainable development of concrete *** paper provides a comprehensive review of the latest developments in self-healing *** begins by summarizing the methods used to evaluate the self-healing efficiency of ***,it compares strategies for achieving healing *** then discusses the typical approaches for developing self-healing ***,critical insights are proposed to guide future studies on the development of novel self-healing *** review will be useful for researchers and practitioners interested in the field of self-healing concrete and its potential to improve the durability,resilience,and safety of concrete infrastructure.

关键词： resilient infrastructure sustainable concrete self-healing cracks

Central cell:the key to determine persistent pollen tube attraction or termination

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Science China(Life Sciences) 2024年第9期67卷 2030-2032页

作者： jiang-Guo Meng Shi-zhen Li Hong-Ju Li Center for Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation Integrative Science Center of Germplasm Creation Western China(Chongqing)Science CitySchool of Life SciencesSouthwest UniversityChongqing400715 China Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Center for Molecular Agrobiology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China

Most eukaryotic species depend on sexual reproduction,characterized by fertilization,to produce a new *** process requires the transfer of sperm(male gamete),containing half of the genetic information,from the male to the egg cell(female gamete),which holds half of the maternal genome,within the female reproductive *** strategies have been evolved to ensure fertilization success in plants.

关键词： organs termination holds

Improved Variable Forgetting Factor Proportionate RLS Algorithm with Sparse Penalty and Fast Implementation Using DCD Iterations

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China Communications 2024年第10期21卷 16-27页

作者： Han zhen Zhang Fengrui Zhang Yu Han Yanfeng jiang Peng GNSS Research Center Wuhan UniversityWuhan 430072China School of Information Science and Technology Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The proportionate recursive least squares(PRLS)algorithm has shown faster convergence and better performance than both proportionate updating(PU)mechanism based least mean squares(LMS)algorithms and RLS algorithms with a sparse regularization *** this paper,we propose a variable forgetting factor(VFF)PRLS algorithm with a sparse penalty,e.g.,l_(1)-norm,for sparse *** reduce the computation complexity of the proposed algorithm,a fast implementation method based on dichotomous coordinate descent(DCD)algorithm is also *** results indicate superior performance of the proposed algorithm.

关键词： dichotomous coordinate descent proportionate matrix RLS sparse systems variable forgetting factor

Deliberate self-harm among pediatric psychiatric inpatients in China:A single-center retrospective study

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World Journal of Psychiatry 2024年第3期14卷 398-408页

作者： Xing-Zhi jiang Huan-Huan Li zhen-zhen Yu Chen Wang Department of Child and Adolescent Psychiatry Shenzhen Kangning HospitalShenzhen Mental Health CenterShenzhen Key Laboratory for Psychological Healthcare and Shenzhen Institute of Mental HealthShenzhen 518020Guangdong ProvinceChina Department of Psychiatry Xiamen Xianyue HospitalXiamen 361012Fujian ProvinceChina Department of Geriatric Medicine Dalian Medical UniversityDalian 116000Liaoning ProvinceChina Department of Neurology The Second Affiliated Hospital of Xiamen Medical CollegeXiamen 361000Fujian ProvinceChina Department of Neurology and Department of Neuroscience The First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina

BACKGROUND For children and adolescents,deliberate self-harm(DSH)is becoming a mental health problem of *** several studies on the prevalence and factors of DSH in the world,there is little information on DSH among children and adolescents in *** study explores the prevalence,types,associated risk factors and tendency of DSH in pediatric psychiatric inpatients in *** To understand the situation of DSH among hospitalized children and adolescents and its related *** In this study,we retrospectively studied 1414 hospitalized children and adolescents with mental illness at Xiamen Mental Health Center from 2014 to 2019,extracted the demographic and clinical data of all patients,and analyzed clinical risk factors of *** A total of 239(16.90%)patients engaged in at least one type of DSH in our ***(n=115,48.12%)was the most common type of ***(n=171,71.55%)were more likely to engage in DSH than males(n=68,28.45%).DSH was positively associated with depressive disorders[OR=3.845(2.196-6.732);P<0.01],female[OR=2.536(1.815-3.542);P<0.01],parental marital status[OR=5.387(2.254-12.875);P<0.01]and negative family history of psychiatric illness[OR=7.767(2.952-20.433);P<0.01],but not with occupation,substance use and history of physical *** Our findings suggest that for patients with depression,females,an abnormal marriage of parents,and no history of mental illness,attention should be paid to the occurrence of DSH.

关键词： Deliberate self-harm Children Adolescent Psychiatric inpatients Retrospective study

Effects of proton pump inhibitors on inflammatory bowel disease:An updated review

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World Journal of Gastroenterology 2024年第21期30卷 2751-2762页

作者： Yu Liang zhen Meng Xue-Li Ding Man jiang Department of Pharmacy The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina Department of Intervention The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

Inflammatory bowel disease(IBD)is believed to be caused by various factors,including abnormalities in disease susceptibility genes,environmental factors,immune factors,and intestinal *** pump inhibitors(PPIs)are the primary drugs used to treat acid-related *** are also commonly prescribed to patients with *** studies have suggested a potential association between the use of certain medications,such as PPIs,and the occurrence and progression of *** this review,we summarize the potential impact of PPIs on IBD and analyze the underlying *** findings may provide insights for conducting further investigations into the effects of PPIs on IBD and serve as an important reminder for physicians to exercise caution when prescribing PPIs to patients with IBD.

关键词： Drug safety Proton pump inhibitor Inflammatory bowel disease Ulcerative colitis Crohn’s disease

Highly Aligned Graphene Aerogels for Multifunctional Composites

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Nano-Micro Letters 2024年第6期16卷 276-342页

作者： Ying Wu Chao An Yaru Guo Yangyang Zong Naisheng jiang Qingbin zheng Zhong‑zhen Yu Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhenGuangdong 518172People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal *** maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been *** unique combination of aligned structure,high surface area,excellent electrical conductivity,mechanical stability,thermal conductivity,and porous nature of highly aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse *** review provides a comprehensive overview of recent advances in highly aligned graphene aerogels and their *** highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively and *** oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular *** review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability for electronics,environmental applications,thermal management,and energy *** and potential opportunities are proposed to offer new insights into prospects of this material.

关键词： Highly aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications

Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers

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Green Energy & Environment 2024年第9期9卷 1336-1365页

作者： Kaili Wang Tingting Zhou zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong jiang School of Chemistry & Chemical Engineering and Environmental Engineering Weifang University Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems CAS Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences College Engineering and Physical Sciences and School of Energy Resources University of Wyoming

The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future.

关键词： PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading