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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Xue, Yuan-Yuan Wang, Zu-Jun Ma, Wu-Ying Liu, Min-Bo He, Bao-Ping Gou, Shi-Long Northwest Inst Nucl Technol State Key Lab Intense Pulsed Irradiat Simulat & Ef Xian 710024 Peoples R China Peking Univ Sch Phys State Key Lab Artificial Microstruct & Microscop P Beijing 100871 Peoples R China

This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor (CIS) following irradiation with back-streaming white neutrons from white neutron sources at the China spallation neutron source (CSNS) and Xi'an pulsed reactor (XAPR). The mean dark signal, dark signal non-uniformity (DSNU), dark signal distribution, and hot pixels of the CIS were compared between the CSNS back-n and XAPR neutron irradiations. The non-ionizing energy loss and energy distribution of primary knock-on atoms in silicon, induced by neutrons, were calculated using the open-source package Geant4. An analysis combining experimental and simulation results showed a noticeable proportionality between the increase in the mean dark signal and the displacement damage dose (DDD). Additionally, neutron energies influence DSNU, dark signal distribution, and hot pixels. high neutron energies at the same DDD level may lead to pronounced dark signal non-uniformity and elevated hot pixel values.

关键词： Displacement damage effects CMOS image sensor (CIS) CSNS back-n XAPR neutrons Geant4 Dark signal non-uniformity (DSNU) PROTON

Data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong Wang Da Shu Shou-qin Zhu Xiao-yuan Ji Bao-de Sun Shanghai key lab.of Advanced high-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State key lab.of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State key lab.ratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

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Reversible aqueous aluminum metal batteries enabled by a water-in-salt electrolyte

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Green Energy & Environment 2024年第7期9卷 1183-1191页

作者： Wenjing Tang Lijun Deng Longyuan Guo Shoubin Zhou Qinhai Jiang Jiayan Luo Shanghai key lab.of Advanced high-temperature Materials and Precision Forming State School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China School of Science Harbin Institute of TechnologyShenzhenGuangdong518055China key lab.ratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China HuaFu high Technology Energy Storage CO. LTDYangzhou225600China Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering Shaoxing312000China

Aluminum(Al),the most abundant metallic element on the earth crust,has been reckoned as a promising battery material for its the highest theoretical volume capacity(8046 mAh cm^(-3)).Being rechargeable in ionic liquid electrolytes,however,the Al anode and battery case suffer from *** the other hand,Al is irreversible in aqueous electrolyte with severe hydrogen evolution ***,we demonstrate a water-in-salt aluminum ion electrolyte(WISE)based on Al and lithium salts to tackle the above *** the WISE system,water molecules can be confined within the Li^(+)solvation *** diminished Al^(3+)-H_(2)O interaction essentially eliminates the hydrolysis effect,effectively protecting Al anode from ***,long-term Al plating/stripping can be ***,two types of high-performance full batteries have been demonstrated using copper hexacyanoferrate(CuHCF,a Prussian Blue Analogues)and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM)as *** reversibility of Al anode laid the foundation for low cost rechargeable batteries suffering for large-scale energy *** context:Al batteries are expected to become a safe and sustainable alternative to lithium *** decades,chase for a feasible Al secondary battery has not been *** key challenge is to find suitable cathode and electrolyte materials,together with which Al anode battery can function ***,fatal drawbacks have impeded the practical application of Al metal batteries(AMBs),such as sustained corrosion of Al anode and battery case in ionic liquid electrolytes,irreversibility issues as well as severe hydrogen evolution reaction during cycling in aqueous ***,electrolyte and their electrochemical kinetics play a vital role in the performance and environmental operating limitations of high-energy Al metal *** this work,we demonstrate a nearly neutral Al ion water-in-salt electrolyte(WISE)to tackle the above chal

关键词： Water-in-salt electrolyte Rechargeable aluminum anode Solvation sheath Hybrid battery Abundance

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Structural and Ferroelectric Transition in Few-Layer HfO_(2) Films by First Principles Calculations

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Chinese physics Letters 2024年第8期41卷 94-106页

作者： Ruiling Gao Chao Liu Bowen Shi Yongchang Li Bing Luo Rui Chen Wenbin Ouyang Heng Gao Shunbo Hu Yin Wang Dongdong Li Wei Ren Materials Genome Institute State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of High Temperature SuperconductorsInternational Center of Quantum and Molecular StructuresPhysics DepartmentInstitute for the Conservation of Cultural HeritageShanghai UniversityShanghai 200444China Hefei national Research Center for physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Shanghai World Foreign Language Academy Shanghai 200233China key lab.ratory of Silicate Cultural Relics Conservation(Ministry of Education) Shanghai UniversityShanghai 200444China Hongzhiwei Technology(Shanghai)Co. Ltd.Shanghai 201206China Zhangjiang lab.ratory Shanghai 201210China

The discovery of ferroelectricity in HfO_(2)-based materials with high dielectric constant has inspired tremendous research interest for next-generation electronic ***,films structure and strain are key factors in exploration of ferroelectricity in fluorite-type oxide HfO_(2) *** we investigate the structures and straininduced ferroelectric transition in different phases of few-layer HfO_(2) films(layer number𝑁=1–5).It is found that HfO_(2) films for all phases are more stable with increasing films *** them,the Pmn2_(1)(110)-oriented film is most stable,and the films of𝑁=4,5 occur with a𝑃21 ferroelectric transition under tensile strain,resulting in polarization about 11.8μC/cm^(2) along in-plane𝑎-*** ferroelectric transition is caused by the strain,which induces the displacement of Hf and O atoms on the surface to non-centrosymmetric positions away from the original paraelectric positions,accompanied by the change of surface Hf–O bond *** importantly,three new stable HfO_(2)2D structures are discovered,together with analyses of computed electronic structures,mechanical,and dielectric *** work provides guidance for theoretical and experimental study of the new structures and strain-tuned ferroelectricity in freestanding HfO_(2) films.

关键词： properties ferroelectric positions

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Remarkable average thermoelectric performance of the highly oriented Bi(Te,Se)-based thin films and devices

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Journal of Materiomics 2024年第2期10卷 366-376页

作者： Zhiliang Li Xiaoqi Yang Zhi Gao Jingxuan Wang Yuli Xue Jianglong Wang Qian Cao Zhihai Ding Shufang Wang Hebei key lab.of Optic-Electronic Information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei ProvinceCollege of Physics Science and TechnologyHebei UniversityBaoding071002China Huabei Cooling Device Co. LtdXianghe065400China

Bi(Te,Se)-based compounds have attracted lots of attention for nearly two centuries as one of the most successful commercial thermoelectric(TE)materials due to their high performance at near room *** with 3D bulks,2D thin films are more compatible with modern semiconductor technology and have unique advantages in the construction of micro-and *** device applications,high average TE performance over the entire operating temperature range is ***,highly c-axis-oriented N-type Bi(Te,Se)epitaxial thin films have been successfully prepared using the pulsed laser deposition technology by adjusting the deposition *** film deposited at~260℃demonstrate a remarkable average power factor(PFave)of~24.4 mW·cm^(-1)·K^(-2)over the tem-perature range of 305e470 K,higher than most of the state-of-the-art Bi(Te,Se)-based ***,the estimated average zT value of the film is as high as~*** then constructed thin-film TE devices by using the above oriented Bi(Te,Se)films,and the maximum output power density of the device can reach up to~30.1 W/m^(2)under the temperature difference of 40 ***,the outstanding average TE performance of the highly oriented Bi(Te,Se)thin films will have an excellent panorama of applications in semiconductor cooling and power generation.

关键词： Bismuth telluride Oriented thin film Thermoelectric device Average power factor Output power density

Deuterium Clusters Fusion Induced by the intense Femtosecond Laser Pulse

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Chinese physics Letters 2007年第2期24卷 494-496页

作者：刘红杰郑志坚谷渝秋张保汉李镛周南性模韩载旻李勇雨芮权海陈家斌王红斌焦春晔何颖玲温天舒温贤仑陈铭 Laser fusion research center China Academy of Engineering Physics Mianyang China 621900 national key lab. of high temperature intense plasma -phys-ics Mianyang China 621900 Korea Atomic Energy Research Institute P.O.BOX 105 Yuseong Daejeon 305-600 Korea

Neutrons （2.45MeV） from deuterium cluster fusion induced by the intense femtosecond （3Ors） laser pulse are experimentally demonstrated. The average neutron yield 103 per shot is obtained. It is found that the yield slightly increases with the increasing laser spot size. No neutron can be observed when the laser intensity I 〈 4.3 × 10^15 W/cm^2.

关键词： high-ENERGY IONS NUCLEAR-FUSION ELECTRON GENERATION ATOMIC CLUSTERS JET EXPLOSIONS EMISSION

Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH2/Nafion composite membranes

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GREEN ENERGY & ENVIRONMENT 2024年第11期9卷 1734-1746页

作者： Li, Xu Zhang, Dongwei Chen, Si Geng, Yingzhao Liu, Yong Qian, Libing Chen, Xi Li, Jingjing Fang, Pengfei He, Chunqing Wuhan Univ Sch Phys & Technol Key Lab Nucl Solid State Phys Hubei Prov Wuhan 430072 Peoples R China Hubei Univ Sci & Technol Sch Nucl Technol & Chem & Biol Xianning 437100 Peoples R China Foshan Univ Sch Mat Sci & Hydrogen Energy Guangdong Key Lab Hydrogen Energy Technol Foshan 528000 Peoples R China

high-performance proton exchange membranes are of great importance for fuel cells. Here, we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH2 (PCP-MCN), a kind of hybrid metal organic framework, which exhibits a superior proton conductivity. PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes. Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated. Significant enhancement in proton conduction for PCP-MCN around 55 degrees C is interestingly found due to the thermal motion of the PCP molecular chains. Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains, i.e., the formation of substantial acid-base pairs (-SO3 ...H+-NH-), which further improves compatibility between additive and Nafion matrix. At the same humidity and temperature condition, the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion. Proton conductivity (sigma) over wide ranges of humidities (30 100% RH at 25 degrees C) and temperatures (30 98 degrees C at 100% RH) for prepared membranes is measured. The sigma in PCPMCN/Nafion composite membranes is remarkably enhanced, i.e. 0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98 degrees C and 100% RH, because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation- deprotonation processes. The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN. In particular, when 3 wt.% PCP-MCN was added to Nafion, the power density of a single-cell fabricated with this composite membrane reaches imp

关键词： Nafion composite membrane Surface-modified MIL-101-Cr-NH2 Proton conductivity Single-cell performance METAL-ORGANIC FRAMEWORK FUEL-CELLS GRAPHENE OXIDE HYBRID MEMBRANE NAFION MATRIX ACID DURABILITY SUPERPLASTICIZERS ANNIHILATION DENSITY

Simulation Study on the Heat Transfer Characteristics of a Spray-Cooled Single-Pipe Cooling Tower

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2109-2126页

作者： Kaiyong Hu Zhaoyi Chen Yunqing Hu Huan Sun Zhili Sun Tonghua Zou Jinghong Ning Tianjin key lab.of Refrigeration Technology Department of Refrigeration and Low Temperature EngineeringTianjin University of CommerceTianjin300134China Jiangsu Yongzhiyu Technology Development Co. Ltd.Xuzhou221700China Shandong Onar Refrigeration Technology Co. Ltd.Binzhou256600China

The current study focuses on spray cooling applied to the heat exchange components of a cooling *** optimization of such processes is attempted by assessing different spray flow rates and droplet *** simplicity,the heat exchanger of the cooling tower is modeled as a horizontal round tube and a cooling tower spray cooling model is developed accordingly using a computational fluid dynamics(CFD)*** study examines the influence of varying spray flow rates and droplet sizes on the heat flow intensity between the liquid layer on the surface of the cylindrical tube and the surrounding air,taking into account the number of *** is observed that on increasing the spray flow strength,the heat flow intensity and extent of the liquid film in the system are enhanced ***,the magnitude of droplet size significantly impacts heat transfer.A larger droplet size decreases evaporation in the air and enhances the deposition of droplets on the round *** facilitates the creation of the liquid film and enhances the passage of heat between the liquid film and *** the number of nozzles,while maintaining a constant spray flow rate,results in a decrease in the flow rate of each individual *** decrease is not favorable in terms of heat transfer.

关键词： Spray cooling droplet sizes number of nozzles CFD

Negative enthalpy alloys and local chemical ordering:a concept and route leading to synergy of strength and ductility

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national Science Review 2024年第4期11卷 172-184页

作者： Zibing An Tao Yang Caijuan Shi Shengcheng Mao Lihua Wang Ang Li Wei Li Xianmeng Xue Ming Sun Yifan Bai Yapeng He Fuzeng Ren Zhouguang Lu Ming Yan Yang Ren Chain-Tsuan Liu Ze Zhang Xiaodong Han Beijing key lab.of Microstructure and Property of Advanced Materials College of Materials Science &Engineering Beijing University of Technology Department of Materials Science and Engineering City University of Hong Kong key lab.ratory of Partial Acceleration physics& Technology Institute of High Energy PhysicsChinese Academy of Sciences Department of Materials Science &Engineering Southern University of Science and Technology Department of physics City University of Hong Kong State key lab.ratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering(LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys(RHEAs). In contrast to conventional ‘trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength(1160 MPa) and uniform ductility(24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

关键词： negative enthalpy alloys local chemical ordering strength ductility dislocation

Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

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Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi Liu Wenjie Xu Shichao Xu Haifeng Wu Baoli Zhang Li Song Zhen-Gang Wang State key lab.ratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China national Synchrotron Radiation lab.ratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions