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Retaining the self-released chalcogenate at reconstructed cobalt sites by self-transformed carbonate regulation for boosted oxygen evolution

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Journal of Energy Chemistry 2024年第10期97卷 46-54页

作者： Jingxuan zhao Zhe Xue Qing Wang Xiangyang Li Shoujie Liu Xu zhao School of Chemical Engineering and Technology Xi'an Jiaotong University Key Laboratory of Materials Physics Institute of Solid State Physics Hefei Institutes of Physical Science (HFIPS) Chinese Academy of Sciences School of Materials Science and Engineering Anhui University

The in-situ generated oxyanions at electrochemically reconstructed catalysts from metal-based nonoxide compounds have been proven to significantly accelerate oxygen evolution reaction（OER） ***,it remains a challenge to retain these self-released oxyanions at reconstructed catalysts,hindering its utilization as a tool to develop efficient OER ***,we demonstrate a versatile selftransformed carbonate regulation strategy to efficiently retain the self-released chalcogenate at Co oxyhydroxides reconstructed from carbon-incorporated Co selenides under OER *** selftransformed CO32-can induce electron accumulation and narrow d bond at Co sites to facilitate the Co3d-O 2p orbital hybridization between Co sites and SeOx2-for enhanced SeOx2-retention,which can accelerate the rate-limiting step for*OOH formation during *** to CoOOH-SeOx2-with limited SeOx2-residues,CoOOH-CO32-/SeOx2-with elevated SeOx2-retention by CO32-regulation exhibited a 5.6-fold increase in current density and a remarkable lower Tafel slope towards *** strategy paves a rational avenue to design efficient catalysts for electrooxidation reactions through finely regulating self-released oxyanions at reconstructed structures.

关键词： Carbonate regulation Chalcogenate retention Electrochemical reconstruction Orbital hybridization Oxygen evolution reaction

Clarification of the dispersion mechanism of cathode slurry of lithium-ion battery under effects of both poly vinylidene fluoride/carbon black ratio and mixing time

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Particuology 2024年第5期88卷 116-127页

作者： Zhilong Wang Zhenzhen zhao Ye Yang An Zhang Xiayi Liu Tong zhao Yahui Cui School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China

This paper presents the effects of both poly vinylidene fluoride(PVDF)/carbon black(CB)ratio(m PVDF:m CB)and mixing time t on the dispersion mechanism of the cathode slurry of lithium-ion battery(LIB).The dispersion mechanism is deduced from the electrochemical,morphological and rheological properties of the cathode slurry by using electrical impedance spectroscopy(EIS),scanning electron microscopy and rheology methods,*** the perspective of EIS method,static simulation models are established in the COMSOL Multiphysics software;meanwhile,the simulated results are used to verify the correctness of the electrochemical properties of the cathode *** a result,the following conclusions are able to be ***,in the case of the mass ratio m_(PVDF):m_(CB)=5:10,LiCoO_(2) particles are completely coated by the mixture of CB and PVDF to form a stable polymer gel *** or lower m_(PVDF):m_(CB) leads to the larger impedance and worse dispersion status for the cathode ***,when t=6 min,a good gel-like conductive network structure is formed by coating the thinner evenly dispersed CB–PVDF double layer around LiCoO_(2) ***,a strategy regarding to both m_(PVDF):m_(CB) and t in experimental scale is proposed,which has the capability of improving the performance of LIB.

关键词： Cathode slurry Dispersion mechanism Lithium-ion battery(LIB)

Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample

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Journal of Forestry Research 2024年第3期35卷 167-174页

作者： Chenxi Xu Yaru zhao Wenling An Qingyu zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People's Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People's Republic of China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049People's Republic of China Graduate School of Environment Studies Nagoya UniversityNagoya 4648601Japan

Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each ***,we developed a method by which each proxy can be measured in the same ***,the sample is polished for ring width *** obtaining the ring width data,the sample is cut to form a 1-mm-thick wood *** sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray ***,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,*** density and the element content are ***,cellulose is isolated from the 1-mm wood plate by removal of lignin,and *** producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)*** on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research.

关键词： Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes

Switchable shape memory polymer bio-inspired adhesive and its application for unmanned aerial vehicle landing

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Chinese Journal of Aeronautics 2024年第3期37卷 380-390页

作者： Qingsong HE Zefang zhao Qiyun ZHONG Siyuan LIU Kai DENG Yongqi LIU Ning ZHANG Zijie zhao Fengjiang ZHAN Jianfeng zhao Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-Sized UAV Ministry of Industry and Information TechnologyUnmanned Aerial Vehicles Research InstituteNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Functional Morphology and Biomechanics Institute of ZoologyKiel UniversityKiel 24098Germany

Controlled and switchable adhesion is commonly observed in biological *** recent years,many scholars have focused on making switchable bio-inspired ***,making a bio-inspired adhesive with high adhesion performance and excellent dynamic switching properties is still a challenge.A Shape Memory Polymer Bio-inspired Adhesive(SMPBA)was successfully developed,well realizing high adhesion(about 337 kPa),relatively low preload(about90 kPa),high adhesion-to-preload ratio(about 3.74),high switching ratio(about 6.74),and easy detachment,which are attributed to the controlled modulus and contact area by regulating temperature and the Shape Memory Effect(SME).Furthermore,SMPBA exhibits adhesion strength of80–337 kPa on various surfaces(silicon,iron,and aluminum)with different roughness(Ra=0.021–10.280)because of the conformal contact,reflecting outstanding surface *** finite element analysis verifies the bending ability under different temperatures,while the adhesion model analyzes the influence of preload on contact area and ***,an Unmanned Aerial Vehicle(UAV)landing device with SMPBA was designed and manufactured to achieve UAV landing on and detaching from various *** study provides a novel switchable bio-inspired adhesive and UAV landing method.

关键词： Bio-inspired adhesive Shape memory polymers Switchable adhesive Unmanned aerial vehicle Landing

Cascaded channel decoupling based solution for RIS regulation matrix

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Intelligent and Converged Networks 2024年第1期5卷 19-27页

作者： Yajun zhao Beijing Institute of Technology Beijing 100081China ZTE Corporation Beijing 100029China

This article presents a pioneering solution to address the challenges of reconfigurable intelligent surface(RIS),employing a cascaded channel decoupling *** novel method streamlines the RIS regulation matrix by dividing the process of electromagnetic wave modulation into two separate sub-processes:virtual receiving response and virtual regular transmission,resulting in the decoupling of the RIS cascaded ***,the paper explores the practical implementation of this channel decoupling method in two typical scenarios,including single-user and multi-user access,offering detailed insights into its *** numerical simulations,the article demonstrates the effectiveness and reduced complexity of the proposed scheme in enhancing the efficiency of the RIS regulation matrix.

关键词： reconfigurable intelligent surface channel decoupling receiving matrix transmitting matrix

Principal components of nuclear mass models

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 65-71页

作者： Xin-Hui Wu Pengwei zhao Department of Physics Fuzhou UniversityFuzhou 350108China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Principal component analysis(PCA)is employed to extract the principal components(PCs)present in nuclear mass models for the first *** effects from different nuclear mass models are reintegrated and reorganized in the extracted *** PCs are recombined to build new mass models,which achieve better accuracy than the original theoretical mass *** comparison indicates that using the PCA approach,the effects contained in different mass models can be collaborated to improve nuclear mass predictions.

关键词： nuclear mass principal component analysis nuclear models statistical methods

Trajectory of COVID-19 response and management strategy in China:scientific rationale driven strategy adjustments

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Frontiers of Medicine 2024年第1期18卷 19-30页

作者： Zeyu Zhang Yue Yan Lina zhao Yizhou Bian Ning zhao You Wu Dahai zhao Zongjiu Zhang Institute for Hospital Management Tsinghua UniversityBeijing100084China School of Medicine Tsinghua UniversityBeijing100084China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai200030China Yale University-Shanghai Jiao Tong University Joint Center for Health Policy Shanghai Jiao Tong UniversityShanghai200030China

The pneumonia caused by novel coronavirus SARS-CoV-2 infection in early December 2019,which was later named coronavirus disease 2019(COVID-19)by the World Health Organization(WHO),rapidly spread across the *** has made extraordinary efforts to this unprecedented pandemic,put its response and control at a very high level of infectious disease management(Category B but with measures for Category A),given top priority to the people and their lives,and balanced the pandemic control and socio-economic *** more than three years’fighting against this disease,China downgraded the management of COVID-19 to Category B infectious disease on January 8,2023 and the WHO declared the end of public health emergency on May 5,***,the ending of pandemic does not mean that the disease is no longer a health *** against COVID-19 from China and the whole world should be learned to prepare well for the future public health *** article gives a systematic review of the trajectory of COVID-19 development in China,summarizes the critical policy arrangements and provides evidence for the adjustment during policy making process,so as to share experiences with international community and contribute to the global health for all humanity.

关键词： COVID-19 public health response and control strategy science-based policy making

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边缘检测眼底图像屈光度测量的研究

计算机工程与应用 2011年第9期47卷 204-206页

作者：赵俊奇陈安世郭智勇阎洁中北大学光电仪器厂太原030051 清华大学环境工程系北京100084

为了解决人眼屈光度测量精度问题,提出了一套基于眼底视网膜图像处理的眼睛屈光度参数测量方法。该方法将从眼底视网膜上反射成像在CCD上的六点红外图像采集到计算机中处理。首先定位六点区域,然后利用边缘CANNY检测算子对六个区域分别... 详细信息

为了解决人眼屈光度测量精度问题,提出了一套基于眼底视网膜图像处理的眼睛屈光度参数测量方法。该方法将从眼底视网膜上反射成像在CCD上的六点红外图像采集到计算机中处理。首先定位六点区域,然后利用边缘CANNY检测算子对六个区域分别图像去噪、平滑处理和边缘检测,最后再用最小二乘拟合的方法计算测量图像的中心,求出眼睛屈光度。实验用标准模拟眼进行了检测,并与二值化法进行了比较,精度明显提高。实验结果表明,该方法使测量精度能达到±0.25D,达到国家计量部门的要求。

关键词：屈光度测量 CANNY算子边缘检测最小二乘法

Vitamin A regulates mitochondrial biogenesis and function through p38 MAPK‑PGC‑1α signaling pathway and alters the muscle fiber composition of sheep

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Journal of Animal Science and Biotechnology 2024年第2期15卷 898-910页

作者： Pengkang Song Jiamin zhao Fanqinyu Li Xiaoyi zhao Jinxin Feng Yuan Su Bo Wang Junxing zhao College of Animal Science Shanxi Agricultural UniversityTaiguShanxi 030801People’s Republic of China State Key Laboratory of Animal Nutrition and Feeding Department of Animal Nutrition and Feed ScienceCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193People’s Republic of China

Background Vitamin A(VA)and its metabolite,retinoic acid(RA),are of great interest for their wide range of physiological ***,the regulatory contribution of VA to mitochondrial and muscle fiber composition in sheep has not been *** Lambs were injected with 0(control)or 7,500 IU VA palmitate into the biceps femoris muscle on d 2 after *** the age of 3 and 32 weeks,longissimus dorsi(LD)muscle samples were obtained to explore the effect of VA on myofiber type *** vitro,we investigated the effects of RA on myofiber type composition and intrinsic *** The proportion of type I myofiber was greatly increased in VA-treated sheep in LD muscle at *** greatly promoted mitochondrial biogenesis and function in LD muscle of *** exploration revealed that VA elevated PGC-1αmRNA and protein contents,and enhanced the level of p38 MAPK phosphorylation in LD muscle of *** addition,the number of type I myofibers with RA treatment was significantly increased,and type IIx myofibers was significantly decreased in primary *** with in vivo experiment,RA significantly improved mitochondrial biogenesis and function in primary myoblasts of *** then used si-PGC-1αto inhibit PGC-1αexpression and found that si-PGC-1αsignificantly abrogated RA-induced the formation of type I myofibers,mitochondrial biogenesis,MitoTracker staining intensity,UQCRC1 and ATP5A1 expression,SDH activity,and enhanced the level of type IIx muscle *** data suggested that RA improved mitochondrial biogenesis and function by promoting PGC-1αexpression,and increased type I *** order to prove that the effect of RA on the level of PGC-1αis caused by p38 MAPK signaling,we inhibited the p38 MAPK signaling using a p38 MAPK inhibitor,which significantly reduced RA-induced PGC-1αand MyHC I *** VA promoted PGC-1αexpression through the p38 MAPK signaling pathway,improved mitochondrial biogenesis,and altered

关键词： Mitochondria Muscle fiber type PGC-1α p38 MAPK Retinoic acid Vitamin A