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Improved genetic algorithm based on reinforcement learning for electric vehicle front-end structure optimization design

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Advances in Manufacturing 2024年第3期12卷 556-575页

作者： feng-yao Lyu Zhen-Fei Zhan Gui-Lin Zhou Ju Wang jie Li Xin He Chongqing Jiaotong University Chongqing400074People’s Republic of China Changan Automobile Co.Ltd. Chongqing404100People’s Republic of China

The structural optimization of electric vehicles involves numerous design variables and constraints,making it a complex engineering optimization task over the past *** population-based evolutionary algorithms encounter issues such as converging to local optima and lacking population diversity when tackling such optimization ***,the solutions obtained for the optimization may be flawed or *** address these problems,an improved genetic algorithm(GA)based on reinforcement learning is proposed in this *** proposed method introduces a population delimitation method based on individual fitness *** population is divided into two parts:the excellent population and the ordinary population,and different selection and cross-mutation methods are applied to each part *** efficient crossover and mutation methods are then applied to the ordinary population to enhance the generation of excellent ***,the proposed approach replaces the traditional fixed crossover and mutation rates with a dynamic selection method based on reinforcement learning to enhance optimization efficiency.A markov decision process model is constructed based on GA environment in this *** population state determination method and reward method are designed for reinforcement learning in the GA environment,dynamically selecting the most appropriate genetic parameters based on the current state of the ***,the uncertainty in the manufacturing process is introduced into the optimization problem and the case study results demonstrate that the proposed reinforcement learning-based GA significantly outperforms other evolutionary algorithms when applied to solving the structural optimization of electric vehicles.

关键词： Structure optimization Genetic algorithm(GA) Q-learning

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Spatial-and spin-resolution ARPES and magnetism beamline at SSRF

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Nuclear Science and Techniques 2024年第8期35卷 23-37页

作者： Fang‑Yuan Zhu jie‑feng Cao Xiang‑Yu Meng Jun‑Qin Li Rui Yu ya‑Mei Wang Shan Qiao Bo Zhao Ming‑Zhu Zhang Zhong‑Kai Liu Mei‑Xiao Wang Yong Wang Ren‑Zhong Tai Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China ShanghaiTech Laboratory for Topological Physics School of Physical Science and TechnologyShanghai Tech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

The BL07U beamline is a new extreme ultraviolet and soft X-ray beamline housed in the Shanghai Synchrotron Radiation Facility. Beamlines are used in nano-resolved angle-resolved photoemission spectroscopy(nano-ARPES), spin-resolved angle-resolved photoemission spectroscopy(spin-ARPES), X-ray magnetic circular dichroism spectroscopy, and X-ray magnetic linear dichroism spectroscopy for certain scientific research. The BL07U beamline, which is based on a pair of elliptical polarized undulators and a variable-included-angle plane-grating monochromator, delivers circularly or linear polarized X-rays within the energy range of 50–2000 eV. The beamline features two branches: One dedicated to nano-ARPES,which has a minimum spot size of only ~ 200 nm, and another branch comprising spin-ARPES, a vector magnetic field, and superconductive magnetic end-station.

关键词： Soft X-ray beamline Nano-ARPES Spin-ARPES XMCD/XMLD

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Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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Chinese Journal of Polymer Science 2024年第8期42卷 1122-1133页

作者： ya-Dong Li Hong Li Lu-Kun feng feng Bao Ming-Liang Wang Cai-Zhen Zhu Zhao-Hui Zheng Xiao-Bin Ding Jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling

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Petroleum Science 2024年第2期21卷 741-751页

作者： Shuang-Biao Han Chao-Han Xiang Xin Du Lin-feng Xie jie Huang Cheng-Shan Wang College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China

The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen *** gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been *** on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different *** gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary *** increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to *** origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and *** shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic ***,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived *** discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.

关键词： Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin

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Short-term Association of Meteorological Elements on COVID-19 Pandemic in a Semi-arid City of Northwest China,2021-2022

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Biomedical and Environmental Sciences 2024年第5期37卷 537-542页

作者： feng feng Liu MA Yu Xia CHENG Bo Wen LIU Zong Rui ZHAO Yu Han yaNG jie College of Atmospheric Sciences Key Laboratory of Semi-Arid Climate ChangeMinistry of EducationLanzhou UniversityLanzhou 730000GansuChina Minhe Meteorological Bureau Minhe 810800QinghaiChina

The coronavirus disease 2019(COVID-19)outbreak in late 2019 significantly impacted global *** virus’s rapid spread,with its long incubation period and high infection level,caused substantial disruption to regular social frameworks,production,and lifestyles^([1]).COVID-19 is primarily transmitted through close contact,long-range contaminants,and airborne routes.

关键词： Northwest COV primarily

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Oil-soluble polymer brushes-functionalized nanoMOFs for highly efficient friction and wear reduction

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Friction 2024年第7期12卷 1499-1511页

作者： Jianxi LIU Yong QIAN Dongsheng LI Wei WU Mengchen ZHANG jie yaN Bin LI feng ZHOU State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China Shaanxi Engineering Research Center of Special Sealing Technology Xi'an Aerospace Propulsion InstituteXi'an 710100China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Nanomaterials as lubricating oil additives have attracted significant attention because of their designable composition and structure,suitable mechanical property,and tunable surface ***,the poor compatibility between nanomaterials and base oil limits their further *** this work,we demonstrated oil-soluble poly(lauryl methacrylate)(PLMA)brushes-grafted metal-organic frameworks nanoparticles(nanoMOFs)as lubricating oil additives that can achieve efficient friction reduction and anti-wear *** were synthesized by free-radical polymerization,which was coordinatively grafted onto the surface of the UiO-67 ***,PLMA brushes were grown on the macroinitiator-modified UiO-67 by surface-initiated atom transfer radical polymerization,which greatly improved the lipophilic property of the UiO-67 nanoparticles and significantly enhanced the colloidal stability and long-term dispersity in both non-polar solvent and base *** adding UiO-67@PLMA nanoparticles into the 500 SN base oil,coefficient of friction and wear volume reductions of 45.3%and 75.5%were achieved due to their excellent mechanical properties and oil ***,the load-carrying capacity of 500 SN was greatly increased from 100 to 500 N by the UiO-67@PLMA additives,and their excellent tribological performance was demonstrated even at a high friction frequency of 65 Hz and high temperature of 120℃.Our work highlights oil-soluble polymer brushes-functionalized nanoMOFs for highly efficient lubricating additives.

关键词： MOFs polymer brushes surface modification tribological properties friction reduction anti-wear

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Single-atom catalysis for advanced oxidation and reduction systems in water decontamination

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Rare Metals 2024年第8期43卷 3576-3606页

作者： jie Teng Jin-Hui Xu Wen-Xin Sun Xue-feng Liu Xia Xu Guo-Shuai Liu School of Urban Construction Changzhou UniversityChangzhou 213164China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Water scarcity is an escalating global crisis,posing a severe threat to populations ***,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant *** this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent *** exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction ***,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be *** review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of *** results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,*** oxidation and reduction processes of SACs and functional SACs materials in water purification were ***,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.

关键词： Single-atom catalysis Water treatment Oxidation Reduction

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Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme

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Nuclear Science and Techniques 2024年第4期35卷 15-28页

作者： Xue-Chao Zhao Rui yan Gui-feng Zhu ya-Fen Liu Jian Guo Xiang-Zhou Cai yang Zou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academies in TMSR Energy System Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to ***,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel ***,using plutonium or enriched uranium as the initial fuel for MSR is more *** this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and ***,the structural design and fuel management scheme of the SM-MSR-Pu were ***,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the *** results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be *** a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten *** temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1) over the 50-year operating time,which ensures a long-term safe ***,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will *** achieve an optimal burn-up performance,setting the entire operation time to 30 years is ***,more than 3600 kg of plutonium eventually accumulate in the *** research is required to effectively utilize this accumulated plutonium.

关键词： Molten salt fuel Plutonium utilization ^(233)U TRUs mole fraction Temperature feedback coefficient

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Spherical cationic polymer networks with porphyrin photosensitizer for sustainable and efficient photocatalysis

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Nano Research 2024年第5期17卷 3934-3941页

作者： Lingling Zhang Liwei Wu Junhui Bao Longhui Li Zejun Liu feng Bai jie Ju Xi yao Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China Department of Chemistry City University of Hong KongKowloonHong Kong 999077China

The continuous and sustainable photo-activity on micro-or nano-carriers has always been a key stepping stone in the industrialization of photo-catalysis,photo-synthesis,and ***,we report a new series of positively charged hollow microspheres carrying porphyrin *** hollow spheres are formed through crosslinking of well-ordered porous thin laminates,initiated by co-assembly of regular monomers and those decorated with porphyrin *** the surface of an individual sphere,densely distributed positive sites attract anionic *** superficial porphyrin decomposes the accumulated reactants under 1 *** degradation and release of products,the photoactive sites are thereby *** demonstrate that polymer network(1:10)exhibited superior sustainable photocatalytic performance with complete degradation of methyl orange(MO)in 40 min with no observable performance deterioration after six *** established close loop of adsorption-reaction-release cycle makes possible many efficient and continuous photo-catalytic processes.

关键词： hydrogen bonding assembly porphyrin sustainable photo-activity anionic pollutant

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Diagnosis and treatment of biliary mucinous cystic neoplasms: A single-center experience

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 495-501页

作者： Jun-Jun Jia ya-Fen Cheng Mei-Bao feng Li Liu Ming-Qi Shuai Xiao-Dong Shen Xiao-feng Tang Shu-Sen Zheng Division of Hepatobiliary and Pancreatic Surgery Department of Surgerythe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of International Healthcare Center the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Pathology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Library the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and prognosis of BMCNs in a large single center. Methods: We analyzed 49 patients with BMCNs confirmed by postoperative pathology at the First Afflliated Hospital, Zhejiang University School of Medicine between January 2007 and December 2021. Results: Among the 49 patients, 37 were female(75.5%), and the average age was 57.04 years. Common symptoms included abdominal discomfort, jaundice and fever, while 22 patients(44.9%) had no symptoms. Serum carbohydrate antigen(CA) 19-9 and CA125 concentrations were elevated in 34.8% and 19.6% of patients, respectively. Forty-eight patients had tumors in the intrahepatic bile ducts and only one had a tumor in the extrahepatic bile duct. Forty-eight patients with noninvasive intrahepatic BMCNs were further analyzed in terms of pathological features: 34(70.8%) had low-grade intraepithelial neoplasms(LGINs), and 14(29.2%) had high-grade intraepithelial neoplasms(HGINs). The potential immunohistochemical markers of BMCNs were cytokeratin(CK) 19, CK7, estrogen receptor and progesterone receptor. Follow-up data for 37 patients with intrahepatic BMCNs were obtained. The median overall survival(OS) of BMCNs was not reached. The longest survival time was 137 *** 5-and 10-year OS rates were 100% and 85.4%, respectively. The 5-and 10-year recurrence-free survival(RFS) rates were 93.9% and 80.2%, respectively. Conclusions: BMCNs are rare cystic neoplasms that commonly occur in middle-aged females. BMCNs can only be diagnosed and classified by postoperative pathology, as there are no specific clinical presentations, serological indicators or imaging modalities for preoperative diagnosis. Complete surgical resection is necessary for BMCNs, and the postoperative prognosis is favorable.

关键词： Biliary mucinous cystic neoplasms Low-grade intraepithelial neoplasms High-grade intraepithelial neoplasms Overall survival Recurrence-free survival

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