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Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 157-165,I0005页

作者： Enping wang Liuxuan Luo Yong Feng aiming Wu Huiyuan Li Xiashuang Luo Yangge Guo Zehao Tan Fengjuan Zhu Xiaohui Yan Qi Kang Zechao Zhuang Daihui Yang Shuiyun Shen Junliang Zhang China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 201306China Institute of Fuel Cells Key Laboratory for Power Machinery and Engineering of MOESchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Tangfeng Energy Technology Co.Ltd. Shanghai 201306China State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China Department of Chemical Engineering Columbia UniversityNY 10027USA

The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.

关键词： Platinum Cobalt Manganese Oxygen reduction reaction Ordered intermetallic L1_(2)atomic structure Proton-exchange membrane fuel cell

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基于离散伴随方法的翼型定常/非定常气动优化设计

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复旦学报（自然科学版） 2024年第2期63卷 209-215页

作者：王士源杨爱明复旦大学航空航天系上海200433

为了有效提升翼型的气动性能,本文发展了一种基于离散伴随方法的翼型定常/非定常气动优化设计方法。应用该方法,对给定目标压力下的翼型反设计问题和振荡翼型的时平均阻力优化问题进行了研究,所得结果表明:反设计得到的翼型几何外形与... 详细信息

为了有效提升翼型的气动性能,本文发展了一种基于离散伴随方法的翼型定常/非定常气动优化设计方法。应用该方法,对给定目标压力下的翼型反设计问题和振荡翼型的时平均阻力优化问题进行了研究,所得结果表明:反设计得到的翼型几何外形与目标翼型高度一致;振荡翼型的阻力优化计算经过12次迭代后,时平均阻力降低了约40%。

关键词：离散伴随方法气动优化设计振荡翼型时平均阻力

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基于碳源和碳汇视角的农业绿色发展研究--以四川省为例

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西南金融 2024年第1期 69-80页

作者：王懋雄罗爱明中国人民银行四川省分行四川成都610041 中国人民银行阿坝州分行四川阿坝624000

农业绿色发展事关生态安全、食品安全,事关高质量、可持续发展,是农业供给侧结构性改革的主攻方向,也是实施“双碳”战略和“五位一体”总体布局的具体体现。金融支持农业绿色发展,构建绿色农业品牌,有助于促进生态保护、提升资源利用... 详细信息

农业绿色发展事关生态安全、食品安全,事关高质量、可持续发展,是农业供给侧结构性改革的主攻方向,也是实施“双碳”战略和“五位一体”总体布局的具体体现。金融支持农业绿色发展,构建绿色农业品牌,有助于促进生态保护、提升资源利用效率、确保食品安全、降低碳排放,实现农户增收和农业高质量发展。四川既是我国农业大省,又是生态资源大省,本文以四川为例,从碳源和碳汇角度分析绿色农业的生态和经济效益,探索金融支持农业绿色发展的新模式,力求搭建起政府主导、市场化运作的工作机制,从而为全国的生态文明建设贡献应有的力量。

关键词：低碳农业绿色农业碳源碳汇碳资产碳交易绿色金融可持续发展

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内外生增长作用下中国城市群的人口负增长风险及其异质性

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热带地理 2024年第4期44卷 583-595页

作者：王梅梅王寅刘蔼明董蕴萱毛锦凰兰州大学资源环境学院兰州730000 西安电子科技大学马克思主义学院西安710000 兰州大学经济学院兰州730000

以中国19个城市群所含城市为研究对象,采用第七次人口普查资料等数据,优化模糊逻辑方法,借助ArcGIS和MATLAB平台构建人口流动复杂网络,以人口流动强度表征外生增长,以户籍人口生育率表征内生增长,以儿童比例、老龄化率、平均家庭规模、... 详细信息

以中国19个城市群所含城市为研究对象,采用第七次人口普查资料等数据,优化模糊逻辑方法,借助ArcGIS和MATLAB平台构建人口流动复杂网络,以人口流动强度表征外生增长,以户籍人口生育率表征内生增长,以儿童比例、老龄化率、平均家庭规模、人口密度、性别比5个指标构建人口负增长评价指标体系,用模糊逻辑方法测算人口负增长风险指数,进而用空间回归方法对城市群人口负增长风险的增长机制进行分析。结果表明:1)中国内地城市群的人口负增长风险平均值为0.48,流出型城市的人口负增长风险较流入型城市高。2)提升型城市群人口负增长风险受外生增长(人口流动引起的增长)和内生增长(由户籍生育率引起的增长)作用的共同影响,外生增长的影响更大。壮大型城市群人口负增长风险的动力机制是外生增长,培育型城市群人口负增长风险的动力机制是内生增长。3)根据中国城市群人口负增长风险及其影响因素,19个城市群的人口负增长风险及其机制可以划分为8个类型。综上,文章认为提升型城市群应以注重人口空间均衡,壮大型城市群应充分发挥大城市对人口的“截流”作用,培育型城市群应进行人力“固本”。

关键词：人口负增长风险外生增长内生增长城市群中国

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Leader-follower Optimal Selection Method for Distributed Control System in Active Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 314-323页

作者： Jian Le Liangang Zhao Cao wang Qian Zhou Yang wang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China

aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation and control tasks for an ADN.The distributed information exchange protocols of the distributed generation(DG)group devoted to node voltage regulation or exchange power control are developed using a DG power utilization ratio as the consensus variable.On these bases,this study further investigates the leader optimal selection method for a DG group to improve the response speed of the distributed control system.Furthermore,a single or multiple leader selection model is established to minimize the constraints of the one-step convergence factor and the number of leaders to improve the response speed of the distributed control system.The simulation results of the IEEE 33 bus standard test system show the effectiveness of the proposed distributed control strategy.In addition,the response speed of a DG control group can be improved effectively when the single or multiple leaders are selected optimally.

关键词： Active distribution1network consensus algorithm leader-follower system mixed-integer semidefinite programming optimal distributed control

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Decitabine in combination with idarubicin within a modified busulfan/cyclophosphamide conditioning regimen for patients with advanced myelodysplastic syndrome: A prospective multicenter clinical cohort study

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中华医学杂志(英文版) 2024年第9期137卷 2024 Feb 2页

作者： Cao Yigeng wang Mingyang wang Fuxu Guo Wenwen Ma Yueshen Li Xiaoyun He Yi Pang aiming Zhang Rongli Zhai Weihua Chen Xin Ma Qiaoling Wei Jialin Yang Donglin Huang Yong Feng Dan Liu Jia Gao Xin Wen Shupeng wang Wen wang Tao Li Ying Fang Xiaosheng Li Yingchun Zhang Xiaohan Cai Yun wang Yongqi Cao Weijie Lu Runqing Feng Sizhou Guo Rong Fu Yuewen Du Xin Liu Zhuogang wang Xin wang Ling Ma Liangming Liu Chuanfang Zhang Xuejun Han Mingzhe Jiang Erlie China Department of Hematology Second Hospital of Hebei Medical University Hebei Key Laboratory of Hematology Shijiazhuang Hebei China Center for Information and Resource State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood Diseases Department of Hematopoietic Stem Cell Transplantation Center Haihe Laboratory of Cell Ecosystem Institute of Hematology Blood Diseases Hospital Chinese Academy of Medical Sciences & Department of Hematology Qilu Hospital of Shandong University Jinan Shandong China Department of Hematology State Key Laboratory of Experimental Hematology Shanxi Bethune Hospital Third Hospital of Shanxi Medical University Taiyuan Shanxi China Department of Hematology Qingdao Central Hospital University of Health and Rehabilitation Sciences Qingdao Shandong National Clinical Research Center for Blood Diseases China Department of Hematology Shandong Provincial Hospital Cheeloo College of Medicine Shandong University Jinan Shandong China Department of Hematology Shandong Provincial Hospital Affiliated to Shandong First Medical University Haihe Laboratory of Cell Ecosystem Jinan Shandong China Department of Hematology Shengjing Hospital of China Medical University Shenyang Liaoning China Department of Hematology Shenzhen Second People’s Hospital Institute of Hematology The First Affiliated Hospital of Shenzhen University Shenzhen University School of Medicine Shenzhen Guangdong China Department of Hematology Henan Cancer Hospital Cancer Hospital Affiliated Zhengzhou University Zhengzhou Henan Blood Diseases Hospital China Department of Hematology Department of Hematology The First Affiliated Hospital of Zhengzhou University Zhengzhou Henan China Chinese Academy of Medical Sciences & Peking Union Medical College Tianjin

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Petrogenesis, oxidation state and volatile content of Dongga tonalite in the Gangdese belt, Xizang: Implication for porphyry Cu mineralization

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Acta Geochimica 2024年第2期43卷 280-295页

作者： Liqiang Zhang Xilian Chen Shaohao Zou Deru Xu Xuena wang Hua wang State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China

The Gangdese belt in Xizang has experienced both Jurassic subduction and Cenozoic continental collision processes, making it a globally renowned region for magmatic rocks and porphyry copper deposits. Numerous Jurassic intrusions have been identified in the belt. Apart from the quartz diorite porphyry in the large Xietongmen deposit, the Cu mineralization potential of other Jurassic intrusions in this belt remains unclear. This study presents zircon U–Pb dating and trace elements, apatite major and trace elements as well as published whole-rock geochemical and isotopic data of the Dongga tonalite in the central part of the Gangdese belt, aiming to reveal the petrogenesis, oxidation state, volatile content, and Cu mineralization potential of this intrusion. The Dongga tonalite has a zircon U–Pb age of 179.4 ± 0.9 Ma. It exhibits high whole-rock V/Sc values(8.76–14.6), relatively low apatite CeN/CeN*ratios(1.04–1.28), elevated zircon(Eu/Eu*)Nvalues(an average of 0.44), high Ce4+/Ce3+values(205–1896), and high ?FMQ values(1.3–3.7), collectively suggesting a high magmatic oxygen fugacity. The Dongga tonalite features amphibole phenocrysts, relatively high whole-rock Sr/Y ratios(20.3–58.9), and lower zircon Ti temperatures (502–740 ℃), reflecting a high magmatic water content. Estimation of magmatic sulfur content(0.002–0.024 wt%) based on apatite SO3contents indicates an enriched magma sulfur content. Combined with previous studies and the collected Sr–Nd–Hf isotopes, the Dongga tonalite is derived from juvenile lower crust related with subduction of the Neo-Tethys oceanic slab. When compared with Xietongmen orebearing porphyries, the Dongga tonalite exhibits remarkable similarities with the Xietongmen ore-bearing porphyries in terms of magma source, tectonic background, magmatic redox state, and volatile components, which indicates that the Dongga tonalite has a high porphyry Cu mineralization potential, and therefore, provides important guidance for the future mineralization exploration.

关键词： Tonalite Zircon Apatite Mineralization potential Dongga area Gangdese belt

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Proteomics analysis of coronary atherosclerotic heart disease with different Traditional Chinese Medicine syndrome types before and after percutaneous coronary intervention

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Journal of Traditional Chinese Medicine 2024年第3期44卷 554-563页

作者： wang Zhibo LI Ying wang Daoping MA Bo MIAO Lan REN Junguo LIU Jinghua LIU Jianxun Beijing Key Laboratory of Pharmacology of Chinese Materia Region Institute of Basic Medical SciencesXiyuan HospitalChina Academy of Chinese Medical SciencesNational Clinical Research Center of Cardiovascular Disease of Traditional Chinese Medicine the National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop ScienceChinese Academy of Agricultural Science Department of Cardiology Beijing Anzhen HospitalCapital Medical University

OBJECTIVE: To investigate the underlying protein molecular mechanisms of "Qi stagnation and blood stasis syndrome"(QS) and "Qi deficiency and blood stasis syndrome"(QD), as two subtypes of coronary artery disease(CAD) in Traditional Chinese Medicine(TCM),following percutaneous coronary intervention(PCI).METHODS: In this study, a total of 227 CAD patients with QS and 211 CAD patients with QD were enrolled; all participants underwent PCI. Label-free quantification proteomics were employed to analyze the changes in serum in two subtypes of CAD patients before and 6 months after PCI, aiming to elucidate the intervention mechanism of PCI in treating CAD characterized by two different TCM syndromes.RESULTS: Biochemical analysis revealed significant changes in tumor necrosis factor-α, high density lipoprotein cholesterol, blood stasis clinical symptoms observation, and Gensini levels in both patient groups post-PCI; Proteomic analysis identified 79 and 95 differentially expressed proteins in the QS and QD patient groups, respectively, compared to their control groups.complement C8 alpha chain, complement factor H,apolipoprotein H, apolipoprotein B, plasminogen,carbonic anhydrase 2, and complement factor Ⅰ were altered in both comparison groups. Furthermore,enrichment analysis demonstrated that cell adhesion and connectivity-related processes underwent changes in QS patients post-PCI, whereas lipid metabolism-related pathways, including the peroxisome proliferator-activated receptor signaling pathway and extracellular matrix receptor interaction, underwent changes in the QD group.The protein-protein interaction network analysis further enriched 52 node proteins, including apolipoprotein B,lipoprotein(a), complement C5, apolipoprotein A4,complement C8 alpha chain, complement C8 beta chain,complement C8 gamma chain, apolipoprotein H,apolipoprotein A-Ⅱ, albumin, complement C4-B,apolipoprotein C3, among others. The functional network of these proteins is posited to contribute to the pathophysiology of CAD characterized by TC

关键词： Traditional Chinese Medicine syndrome coronary atherosclerotic heart disease peptide mapping percutaneous coronary intervention proteomics

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Application study of a correction method for a spacecraft thermal model with a Monte-Carlo hybrid algorithm

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Chinese Science Bulletin 2011年第13期56卷 1407-1412页

作者： CHENG WenLong LIU Na LI Zhi ZHONG Qi wang aiming ZHANG ZhiMin HE ZongBo Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei 230027 China Research and Development Center China Academy of Space Technology Beijing 100094 China Beijing Institute of Spacecraft System Engineering Chinese Academy of Space Technology Beijing 100094 China

The correction of a thermal model for a thermally controlled satellite in ground test conditions is studied using a Monte Carlo hybrid algorithm.First,the global and local parameters are summarized according to sensitivity analyses on uncertain parameters,and then the model correction is treated as a parameter optimization problem to be solved with a hybrid algorithm.Finally,the correction of the thermal model is completed using a layered correction method.The sensitivity analysis showed that the effective emissivities across the multi-layer insulation (MLI) and the emissivities of the thermal control coating are global parameters,while the contact heat transfer coefficients are local parameters.After correction,the deviations between the calculated and test values were all within ± 3 ℃.The final results prove that the method in this study is superior to traditional methods and satisfies the requirements for thermal model correction.

关键词：校正方法混合算法热模型蒙特卡洛航天器敏感性分析应用模型修正

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Differentially Private Support Vector Machines with Knowledge Aggregation

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Computers, Materials & Continua 2024年第3期78卷 3891-3907页

作者： Teng wang Yao Zhang Jiangguo Liang Shuai wang Shuanggen Liu School of Cyberspace Security Xi’an University of Posts and TelecommunicationsXi’an710121China

With the widespread data collection and processing,privacy-preserving machine learning has become increasingly important in addressing privacy risks related to individuals.Support vector machine(SVM)is one of the most elementary learning models of machine learning.Privacy issues surrounding SVM classifier training have attracted increasing attention.In this paper,we investigate Differential Privacy-compliant Federated Machine Learning with Dimensionality Reduction,called FedDPDR-DPML,which greatly improves data utility while providing strong privacy guarantees.Considering in distributed learning scenarios,multiple participants usually hold unbalanced or small amounts of data.Therefore,FedDPDR-DPML enables multiple participants to collaboratively learn a global model based on weighted model averaging and knowledge aggregation and then the server distributes the global model to each participant to improve local data utility.aiming at high-dimensional data,we adopt differential privacy in both the principal component analysis(PCA)-based dimensionality reduction phase and SVM classifiers training phase,which improves model accuracy while achieving strict differential privacy protection.Besides,we train Differential privacy(DP)-compliant SVM classifiers by adding noise to the objective function itself,thus leading to better data utility.Extensive experiments on three high-dimensional datasets demonstrate that FedDPDR-DPML can achieve high accuracy while ensuring strong privacy protection.

关键词： Differential privacy support vector machine knowledge aggregation data utility

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