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Journal of Energy Chemistry 2025年第2期101卷 345-384页

作者： Rasoul Salami Yimin Zeng xue Han Sohrab Rohani Ying Zheng Department of Chemical and Biochemical Engineering Western University Canmet MATERIALS Natural Resources Canada

The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased *** the proposed methods,the hydrogenation of CO2to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce *** significant volumes of methanol are currently produced from CO2,developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process *** in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C *** these factors guides us toward developing more effective catalysts for ethanol *** this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or *** catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and *** following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO2into ***,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.

关键词： CO 2 hydrogenation Methanol Ethanol Catalytic mechanism Operando techniques Single atom catalyst Tandem catalyst

Spatiotemporal evolution of wildfire activity during the Paleocene-Eocene Thermal Maximum in China

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Science China Earth Sciences 2025年第2期68卷 509-522页

作者： xue-Ting WANG Zuoling CHEN Linlin CUI Xu WANG State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences College of Earth and Planetary SciencesBeijing 100049China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Paleocene-Eocene Thermal Maximum(PETM)was the most prominent warming event in the Cenozoic and serves as a geological analog for the current global warming driven by anthropogenic CO_(2)emissions from burning fossil *** a primary disruptor of Earth's ecosystems,wildfire activity affects the balance of ecosystems,the global carbon cycle,and climate ***,studying the evolution and driving mechanisms of wildfires during the PETM is essential for predicting wildfire activity under global warming scenarios and for understanding the carbon cycle in the context of wildfire *** research on wildfires during the PETM has mainly focused on the Northern Hemisphere,particularly Europe and North America,whereas studies on Chinese mainland remain *** this study,we analyzed black carbon(BC)concentration and carbon isotope(δ13C)in the Beigou section of the Nanyang Basin and the Xilutian section of the Fushun Basin to reconstruct the spatiotemporal evolution of wildfires in arid/semi-arid and humid *** integrated these findings with those of previous studies on the paleoclimate of the research area to elucidate the driving mechanisms behind wildfire *** results indicate that wildfire activity weakened at the onset of the PETM,with the negative carbon isotope period characterized by low wildfire activity,except for a brief resurgence in the Nanyang *** the recovery phase of the PETM,wildfire activity gradually increased,returning to the pre-PETM *** prolonged low wildfire state was likely caused by extremely high temperatures and precipitation as well as the resulting vegetation *** the PETM recovery phase,increased wildfire activity transformed“short-term carbon sinks”of the biological-atmospheric carbon cycle into“long-term carbon sinks”through the burial of *** process of carbon sink conversion may have acted as a negative feedback mechanism,contributing to carbon sequestration and the e

关键词： PETM Wildfire Carbon cycle Nanyang Basin Fushun Basin

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Design and Application of Turbine Cascade Partitioned Endwall Profiling

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Journal of Thermal Science 2025年第1期34卷 110-128页

作者： ZENG Fei JIANG Ruiqi xue Xingxu DU Wei LUO Lei ZHOU Xun AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412002China School of Energy Science and Technology Harbin Institute of TechnologyHarbin 150001China Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research InstituteTianjin 300270China

The influence of partitioned profiling design based on a large-pitch highly loaded cascade is studied by numerical *** partitioned profile is mainly composed of a pressure-side convex structure near the leading edge and a suction-side convex structure at the midstream and downstream sides of the *** influence of the change in the vertex axial position and peak value of the B-line on the secondary flow control is *** this paper,air(ideal gas)is selected as the flow *** average static pressure at the outlet and the average total temperature at the inlet are kept *** γ-θ is used as the turbulence *** results show that the pressure-side convex structure suppresses the spanwise and pitchwise migration of the inlet flow by adjusting the static pressure distribution of the flow field,so the development of the pressure-side leg of the horseshoe vortex is effectively *** suction-side convex structure adjusts the static pressure distribution of the flow field and increases the included angle between the cross-flow and suction surface,so the accumulation of low-momentum fluid,the development of a corner vortex and the flow separation at the trailing edge of the suction-side surface are all suppressed near the endwall-suction ***,the energy loss coefficient of the large-pitch highly loaded cascade is decreased from 0.0564 to 0.0485,representing a 25% reduction in secondary flow losses.

关键词： large-pitch highly loaded cascade highly loaded design non-axisymmetrical endwall design secondary flow control partitioned endwall profiling

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Bearing Fault Diagnosis Based on the Markov Transition Field and SE-IShufflenetV2 Model

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Structural Durability & Health Monitoring 2025年第1期19卷 125-144页

作者： Chaozhi Cai Tiexin Xu Jianhua Ren Yingfang xue School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan056038China

A bearing fault diagnosis method based on the Markov transitionﬁeld(MTF)and SEnet(SE)-IShufﬂenetV2 model is proposed in this paper due to the problems of complex working conditions,low fault diagnosis accuracy,and poor generalization of rolling ***,MTF is used to encode one-dimensional time series vibration sig-nals and convert them into time-dependent and unique two-dimensional feature ***,the generated two-dimensional dataset is fed into the SE-IShufﬂenetV2 model for training to achieve fault feature extraction and classiﬁ*** paper selects the bearing fault datasets from Case Western Reserve University and Paderborn University to experimentally verify the effectiveness and superiority of the proposed *** generalization performance of the proposed method is tested under the variable load condition and different signal-to-noise ratios(SNRs).The experimental results show that the average accuracy of the proposed method under different working conditions is 99.2%without adding *** accuracy under different working conditions from 0 to 1 HP is 100%.When the SNR is 0 dB,the average accuracy of the proposed method can still reach 98.7%under varying working ***,the bearing fault diagnosis method proposed in this paper is characterized by high accuracy,strong anti-noise ability,and ***,the proposed method can also overcome the inﬂuence of variable working conditions on diagnosis accuracy,providing method support for the accurate diagnosis of bearing faults under strong noise and variable working conditions.

关键词： Bearings Markov transitionﬁeld SE-IShufﬂenetV2

Effects of Shenqi Xiangyi granules in advanced gastric cancer chemotherapy

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 169-175页

作者： Xiao-Jing Shi Yu Song xue-xue Liang Ting Chen Huang-Yu Hao xue Han Ya-Nan Chen Department of Oncology Zhangjiagang First People's HospitalSuzhou 215600Jiangsu ProvinceChina

BACKGROUND Owing to the absence of specific symptoms in early-stage gastric cancer,most patients are diagnosed at intermediate or advanced *** a result,treatment often shifts from surgery to other therapies,with chemotherapy and targeted therapies being the primary options for advanced gastric cancer treatment.A total of 116 patients with advanced gastric cancer,admitted from January 2021 to December 2023,were selected and divided into two groups of 58 each using the random number table *** control group received FOLFOX4 chemothe-rapy(oxaliplatin+calcium+folinate+5-fluorouracil)combined with intravenous *** observation group received the same treatment as the control group,supplemented by oral administration of Senqi Shiyiwei *** groups underwent treatment cycles of 3 weeks,with a minimum of two *** therapeutic efficacy,immune mechanisms,and treatment-related toxicity and side effects were compared between the *** objective remission rate in the observation group(55.17%)was higher than that of the control group(36.21%)(P0.05).CONCLUSION Adjuvant therapy with Shenqixian granules may enhance the efficacy of simudizumab combined with FOLFOX4 chemotherapy in advanced gastric cancer and the immune function by increasing immune cell counts,making it a valuable option in clinical treatment.

关键词： Sindilizumab FOLFOX4 chemotherapy Advanced gastric cancer Ginseng Qi Xiangyi granule Clinic treatment

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： Li Ma Cai Dai Xingsi xue Cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy

Geochronology and geodynamic setting of the carbonate-hosted Pb-Zn deposits in world-class Sichuan-Yunnan-Guizhou triangle,South China

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Acta Geochimica 2025年第1期44卷 217-230页

作者： Zhongxi xue Wenxin Shi Chen Wei Tao Wu Zhilong Huang State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Mining Engineering Guizhou University of Engineering ScienceBijie 551700China Helmholtz-Zentrum Dresden Rossendorf Helmholtz Institute Freiberg for Resource Technology09599 FreibergGermany University of Chinese Academy of Sciences Beijing 100049China

Unraveling the precise mineralization age is vital to understand the geodynamic setting and ore-forming mechanism of the sediment-hosted Pb-Zn deposit;this has long been a *** Sichuan-Yunnan-Guizhou(SYG)triangle in the southwestern margin of the Yangtze Block is a globally recognized carbonate-hosted Pb-Zn metallogenic province and also an essential part of the South China low-temperature metallogenic *** region has>30 million tons(Mt)Zn and Pb resources and shows the enrichment of dispersed metals,such as Ga,Ge,Cd,Se,and *** the past 2 decades,abundant data on mineralization ages of Pb-Zn deposits within the SYG triangle have been documented based on various radioisotopic dating methods,resulting in significant progress in understanding the geodynamic background and ore formation of Pb-Zn deposits hosted in sedimentary rocks at SYG *** paper provides a comprehensive summary of the geochronological results and Pb-Sr isotopic data regarding Pb-Zn deposits in the SYG triangle,which identified two distinct Pb-Zn mineralization periods influencing the dynamic processes associated with the expansion and closure of the Paleo-Tethys Ocean in the western margin of the Yangtze *** predominant phase of Pb-Zn mineralization at SYG triangle spanned from the Middle Triassic to Early Jurassic(226-191 Ma),which was intensely correlated with the large-scale basin fluid transport triggered by the closure of the Paleo-Tethys Ocean and Indosinian *** secondary Pb-Zn mineralization phase occurred during the Late Devonian to Late Carboniferous and was controlled by extensional structures associated with the expansion of the Paleo-Tethys *** investigation is necessary to clarify the occurrence and potential factors involved in the Pb-Zn mineralization events during the Late Devonian to Late Carboniferous.

关键词： Sichuan-Yunnan-Guizhou triangle Carbonate hosted Pb-Zn deposit Radioisotopic dating Geodynamic setting Mississippi Valley-type(MVT)

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Meteorological effects on sources and future projection of nitrogen deposition to lakes in China

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Journal of Environmental Sciences 2025年第5期151卷 100-112页

作者： Cheng Shi Hao Guo xue Qiao Jingsi Gao Ying Chen Hongliang Zhang Department of Biological and Ecological Engineering Oregon State UniversityCorvallisOR 97331USA State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institute of New Energy and Low-carbon Technology Sichuan UniversityChengdu 610065China Engineering Technology Development Center of Urban Water Recycling Shenzhen PolytechnicShenzhen 518055China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200438China

Lake ecosystems are extremely sensitive to nitrogen growth,which leads to water quality degradation and ecosystem health *** depositions,as one of the main sources of nitrogen in water,are expected to change under future climate change ***,it remains not clear how nitrogen deposition to lakes respond to future meteorological *** this study,a source-oriented version of Community Multiscale Air Quality(CMAQ)Model was used to estimate nitrogen deposition to 263 lakes in 2013 and under three RCP scenarios(4.5,6.0 and 8.5)in *** total deposition of 58.2 Gg nitrogen was predicted for all lakes,with 23.3 Gg N by wet deposition and 34.9 Gg N by dry *** and ammonium in aerosol phase are the major forms of wet deposition,while NH3 and HNO_(3)in gas phase are the major forms of dry *** emissions contribute to 57%of wet deposition and 44%of dry *** future meteorological conditions,wet deposition is predicted to increase by 5.5%to 16.4%,while dry deposition would decrease by 0.3%to 13.0%.Changes in wind speed,temperature,relative humidity(RH),and precipitation rates are correlated with dry and wet deposition *** predicted changes in deposition to lakes driven by meteorological changes can lead to significant changes in aquatic chemistry and ecosystem *** from future emission scenarios,different climate scenarios should be considered in future ecosystem health evaluation in response to nitrogen deposition.

关键词： Deposition Nitrogen Lakes CMAQ Meteorological variations

An Online Exploratory Maximum Likelihood Estimation Approach to Adaptive Kalman Filtering

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 228-254页

作者： Jiajun Cheng Haonan Chen Zhirui xue Yulong Huang Yonggang Zhang the College of Intelligent Systems Science and Engineering Harbin Engineering University the Engineering Research Center of Navigation Instruments Ministry of Education the College of Intelligent Systems Science and Engineering the College of Future Technology Harbin Engineering University IEEE

Over the past few decades, numerous adaptive Kalman filters(AKFs) have been proposed. However, achieving online estimation with both high estimation accuracy and fast convergence speed is challenging, especially when both the process noise and measurement noise covariance matrices are relatively inaccurate. Maximum likelihood estimation(MLE) possesses the potential to achieve this goal, since its theoretical accuracy is guaranteed by asymptotic optimality and the convergence speed is fast due to weak dependence on accurate state ***, the maximum likelihood cost function is so intricate that the existing MLE methods can only simply ignore all historical measurement information to achieve online estimation,which cannot adequately realize the potential of MLE. In order to design online MLE-based AKFs with high estimation accuracy and fast convergence speed, an online exploratory MLE approach is proposed, based on which a mini-batch coordinate descent noise covariance matrix estimation framework is developed. In this framework, the maximum likelihood cost function is simplified for online estimation with fewer and simpler terms which are selected in a mini-batch and calculated with a backtracking method. This maximum likelihood cost function is sidestepped and solved by exploring possible estimated noise covariance matrices adaptively while the historical measurement information is adequately utilized. Furthermore, four specific algorithms are derived under this framework to meet different practical requirements in terms of convergence speed, estimation accuracy,and calculation load. Abundant simulations and experiments are carried out to verify the validity and superiority of the proposed algorithms as compared with existing state-of-the-art AKFs.

关键词： Adaptive Kalman filtering coordinate descent maximum likelihood estimation mini-batch optimization unknown noise covariance matrix

Solid-state synthesis of mesoporous metals via mechanochemical coordination self-assembly

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Science China Chemistry 2025年第2期68卷 492-498页

作者： Hailong Xiong Chunyu Qi Lantian xue Ling Zhang Hanyu Liu Zhen-An Qiao State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Mesoporous metals with large surface area,high pore volume,and uniform pore structure hold excellent advantages for various ***,the state-of-the-art synthesis methods are still limited to wet chemistry,which requires excessive solvents and a time-consuming drying ***,we report a facile and general mechanochemical coordination self-assembly strategy to prepare mesoporous metals(e.g.,Rh,Ru,Ir,Pt,Pd,Ag,Co,and Ni)with remarkable porous properties by using metal chlorides and cationic polymer *** with the wet chemistry process,this method proceeds without solvents and does not need complicated experimental conditions and long synthetic periods,which not only greatly reduces the consumption of cost and energy and environmental pollution,but also improves the synthesis efficiency and yield of target *** believe the developed approach will provide a general pathway for the scalable preparation of advanced porous materials.

关键词： mechanochemistry self-assembly mesoporous materials mesoporous metals electrocatalysis