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原子与分子物理学报 1998年第S1期15卷 161-162页

作者：赵仪韩克利何国钟 y.j.yan 西北师大物理系大连化学物理研究所十一室香港科技大学化学系

从密度矩阵方法出发，得出了分子动力学优化控制的线性公式，并进一步简化得到数值上容易实现的简单公式。

关键词：分子动力学优化控制线性控制理论密度矩阵方法波函数控制过程分子系统大连化学物理研究所数值方法优化控制理论

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Transient electromagnetic S-inversion in tunnel prediction

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Transient electromagnetic S-inversion in tunnel prediction

Pseudo-seismic wavelet transformation of transient electromagnetic response in engineering geology exploration

中国科学院地质与地球物理研究所2007学术年会

作者： G.Q.Xue,y.j.yan,X.Li,and Q.y.Di 1 Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing,China. 2 Department of Engineering Mechanics,Northwestern Polytechnical University,Xi’an,China. 3 School of Geology and Survey Engineering,Chang An University, Xi’an,China.

[1]This paper presents S-inversion method to tunnel prediction to forecasting water-filled faults or fracture zones ahead of the front wall of a tunnel during tunnel excavation. S-inversion is an interpretation method of transient electromagnetic(TEM) data using the second derivative of the conductivity parameter based on the moving thin sheet *** iS suggested for the technology of second derivative of vertical apparent conductivity,which iS traditionally used in surface TEM data interpretation,the theoretical analyses and the method of numerical calculation in detail are also ***,a real tunnel forecasting is studied for TEM surveys,and results show that the proposed method is effective and successful for exploring and predicting unfavorable geology during tunnel ***:Xue,G.Q.,***,***,and

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Pseudo-seismic wavelet transformation of transient electroma...

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

中国科学院地质与地球物理研究所2007学术年会

作者： G.Q.Xue,y.j.yan,and X.Li 1 Institute of Geology and Geophysics,Chinese Academy of Sciences, Beijing,China. 2 Department of Engineering Mechanics,Northwestern Polytechnical University,Xi’an,China. 3 School of Geology and Survey Engineering,Chang An University, Xi’an,China.

[1]This paper presents some new theoretical analysis and numerical simulations of that transient electromagnetic diffusion-field response is transformed into a pseudo- seismic wavelet in engineering geology *** can clearly reveal the electric interface under *** simplify the integral equation used in the transformation, the integral range is separated into seven windows,and each window is compiled into a group of integral coefficients. Then,the accuracy of the coefficients is tested,and the calculated coefficients are used to derive the pseudo-seismic wavelet by optimization ***,several geoelectric models are designed,so that model responses are transformed into the pseudo-seismic *** transformed imaginary wave shows that some reflection and refraction phenomena appear when the wave meets the electric *** result supports the introduction of the seismic interpretation in data processing of transient electromagnetic ***:Xue,G.Q.,***,and ***(2007),Pseudo-seismic wavelet transformation of transient electromagnetic response in engineering geology exploration,

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journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang yan Li Libo Chen Handong jiao Zhijing yu jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China Life Sciences 2025年第1期68卷 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng yan Kun jiang Bingbing Song He Li Maomao Cao Dianqin Sun Fan yang Xinxin yan Shaoli Zhang yi Teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute Linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrendyears, smoking, and limited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang yang jianfeng Zheng Guoyu Wang yifei Gao yatao yang jia Li Xiaojin Han yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Ethanol

Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting

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journal of Energy Chemistry 2025年第1期100卷 26-38页

作者： Xiaodong yang Haochen Shen Xiaoming Xiao Zhichao Li Qi Zhou Wei yang Bin jiang yongli Sun Luhong Zhang Zhenhua yan School of Chemical Engineering and Technology Tianjin University Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides （M/SLDH） through spontaneous redox and sulfurization *** developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction （OER） and hydrogen evolution reaction （HER） performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm-2in 1 M KOH,*** both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm-2and exhibited high structural robustness,maintaining stability at 1000 mA cm-2for 300 ***-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water ***,ultraviolet photoelectron spectroscopy （UPS） and density functional theory （DFT） analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER *** study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.

关键词： Ultraviolet photoelectron spectroscopy

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

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journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen Liu Zhen Wu Hao Wang Xudong Zhang yuanzhen Chen yongning Liu Shengwu Guo Shenghua Chen yanli Nan yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp Ltd Network Information Center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558Co0.074O2（L1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to Li1.2Ni0.13Mn0.54Co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co LLOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

小世界、结构洞与城市创新的网络机制:来自长三角城市群的证据

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管理工程学报 2025年第2期39卷 14-26页

作者：袁燕吴妍杨大鹏浙江科技大学经济与管理学院浙江杭州310023 浙江金融职业学院电子商务与新消费研究院浙江杭州310018 中共浙江省委党校工商管理教研部浙江杭州311121

近年来,创新网络作为区域和城市创新驱动力的重要性得到了广泛关注。一些研究将网络关系视为知识在城市内和城市间传播的渠道,并通过网络分析视角洞察城市创新的结构和动态。然而,城市创新的网络机制,特别是数字经济发展背景下的数字赋... 详细信息

近年来,创新网络作为区域和城市创新驱动力的重要性得到了广泛关注。一些研究将网络关系视为知识在城市内和城市间传播的渠道,并通过网络分析视角洞察城市创新的结构和动态。然而,城市创新的网络机制,特别是数字经济发展背景下的数字赋能城市创新能力提升机制还有待进一步研究。本文利用长三角城市群26个城市2009年—2018年联合申请专利数据构建了城市创新网络,探讨了网络结构属性——小世界和结构洞对城市创新能力的影响。结果表明,小世界与城市创新能力呈“倒U型”关系,数字经济发展水平正向调节了二者之间的“倒U型”关系,结构洞对城市创新能力具有正向影响。本文厘清了创新网络结构对城市创新能力的影响,回应了以往研究关于小世界和结构洞对创新影响的理论争议,为区域创新的理论研究提供了新颖性观点,深化了对城市群创新发展规律的认识,对推进中国城市群协同创新具有重要意义。

关键词：创新网络城市创新能力专利合作数字经济

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