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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su ze-yu li li-Le liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

Generation and regulation of electromagnetic pulses generated by femtosecond lasers interacting with multitargets

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Nuclear Science and Techniques 2024年第1期35卷 96-107页

作者： Ya-Dong Xia De-Feng Kong Qiang-You He Zhen Guo Dong-Jun Zhang Tong Yang Hao Cheng yu-ze li Yang Yan Xiao liang Ping Zhu Xing-Long Xie Jian-Qiang Zhu Ting-Shuai li Chen lin Wen-Jun Ma Xue-Qing Yan State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Beijing Laser Acceleration Innovation Center Beijing 101407China Institute of Guangdong Laser Plasma Technology Guangzhou 510540China National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and FineChinese Academy of SciencesShanghai 201800China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(2))femtosecond(fs)lasers with metal flat,plastic flat,and plastic nanowire-array(NWA)*** analyses are conducted on the EMPs in terms of their spatial distribution,time and frequency domains,radiation energy,and *** results indicate that EMPs from metal targets exhibit larger amplitudes at varying angles than those generated by other types of targets and are enhanced significantly for NWA *** a plastic target holder and increasing the laser focal spot can significantly decrease the radiation energy of the ***,the composite shielding materials indicate an effective shielding effect against *** simulation results show that the NWA targets exert a collimating effect on thermal electrons,which directly affects the distribution of *** study provides guidance for regulating EMPs by controlling the laser focal spot,target parameters,and target rod material and is beneficial for electromagnetic-shielding design.

关键词： Electromagnetic pulses Laser plasma interaction Electromagnetic shielding Electron distribution

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数字技术驱动道路运输安全隐患综合防治

哈尔滨学院学报 2024年第2期45卷 46-49页

作者：周晓光史梁韩毅于立泽黑龙江海康软件工程有限公司黑龙江哈尔滨150000

道路运输系统是由很多因素组成的复杂动态系统,任何一起交通事故的发生都是多种因素共同作用的结果。文章结合大数据、物联网、信息化等数字技术对道路交通主要安全隐患进行精细管理,实现道路交通安全隐患预防预测、实时监管和闭环管理... 详细信息

道路运输系统是由很多因素组成的复杂动态系统,任何一起交通事故的发生都是多种因素共同作用的结果。文章结合大数据、物联网、信息化等数字技术对道路交通主要安全隐患进行精细管理,实现道路交通安全隐患预防预测、实时监管和闭环管理。重点介绍建立道路交通安全隐患研判大数据模型及建立道路交通安全风险主动预防模型,以实现隐患排查治理闭环管理相关技术的应用。

关键词：数字技术道路运输安全隐患综合防治

An Ultrasensitive, Durable and Stretchable Strain Sensor with Crack-wrinkle Structure for Human Motion Monitoring

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Chinese Journal of Polymer Science 2021年第3期39卷 316-326,I0005页

作者： ze-yu li Wei Zhai yun-Fei yu Guo-Jie li Peng-Fei Zhan Jian-Wei Xu Guo-Qiang Zheng Kun Dai Chun-Tai liu Chang-yu Shen Shen Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationSchool of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

Flexible strain sensor has promising features in successful application of health monitoring, electronic skins and smart robotics, ***, we report an ultrasensitive strain sensor with a novel crack-wrinkle structure(CWS) based on graphite nanoplates(GNPs)/thermoplastic urethane(TPU)/polydimethylsiloxane(PDMS) nanocomposite. The CWS is constructed by pressing and dragging GNP layer on TPU substrate,followed by encapsulating with PDMS as a protective layer. On the basis of the area statistics, the ratio of the crack and wrinkle structures accounts for 31.8% and 9.5%, respectively. When the sensor is stretched, the cracks fracture, the wrinkles could reduce the unrecoverable destruction of cracks, resulting in an excellent recoverability and stability. Based on introduction of the designed CWS in the sensor, the hysteresis effect is limited effectively. The CWS sensor possesses a satisfactory sensitivity(GF=750 under 24% strain), an ultralow detectable limit(strain=0.1%) and a short respond time of 90 ms. For the sensing service behaviors, the CWS sensor exhibits an ultrahigh durability(high stability>2×10^(4) stretching-releasing cycles). The excellent practicality of CWS sensor is demonstrated through various human motion tests,including vigorous exercises of various joint bending, and subtle motions of phonation, facial movements and wrist pulse. The present CWS sensor shows great developing potential in the field of cost-effective, portable and high-performance electronic skins.

关键词： Polymer nanocomposites Microstructure Flexible strain sensor Human motion monitoring

Synthesis of Chiral α-Benzyl-β^(2)-hydroxy Carboxylic Acids through Iridium-Catalyzed Asymmetric Hydrogenation of α-Oxymethylcinnamic Acids

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Chinese Journal of Chemistry 2014年第8期32卷 783-787页

作者： ze-yu li Song Song Shou-Fei Zhu Na Guo li-Xin Wang Qi-lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)

An asymmetric hydrogenation of α-oxymethylcinnamic acids was developed by using chiral spiro phosphineoxazoline/iridium complexes as catalysts to prepare β^(2)-hydroxycarboxylic acids with high reactivity(TON up to 2000)and excellent enantioselectivity(up to 99.5%ee).By using this highly efficient asymmetric hydrogenation as a key step,a concise total synthesis of natural product homoisoflavone(S)-(+)-4 was accomplished.

关键词： asymmetric hydrogenation chiral spiro ligands iridium catalysts α-oxymethylcinnamic acids α-benzyl-β^(2)-hydroxy carboxylic acids

Cutibacterium acnes in Atopic Dermatitis:Roles and Potential Therapeutic Applications

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International Journal of Dermatology and Venereology 2024年第1期7卷 12-17页

作者： Tian-ze yu Wei li Department of Dermatology Shanghai Institute of DermatologyHuashan HospitalFudan UniversityShanghai 200040China

Atopic dermatitis(AD)is a chronic relapsing inflammatory skin *** main initiating mechanisms of AD are disruptions in the skin microbiota,dysfunction of the skin barrier,and predominantly elevated type 2 immune *** acnes(***)is a commensal bacterium that is ubiquitous and predominant in healthy skin and shows intraspecific subtype *** abundance of *** is closely related to the sebum secreted by sebaceous *** has long been considered a proinflammatory skin bacterium that drives the development of acne *** evidence indicates that *** promotes skin microbiota homeostasis and skin barrier maintenance;however,the potential role of *** in AD remains largely *** review provides the latest information on the distribution of *** and its phylotypes in healthy skin and AD as well as an overview of the possible role of *** in the pathophysiological pathways underlying ***,the review focuses on new evidence regarding the protective functions of *** and its metabolites in AD and discusses the potential for therapeutic applications.

关键词： atopic dermatitis skin microbiota probiotic therapy

Multiscale spatiotemporal meteorological drought prediction:A deep learning approach

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Advances in Climate Change Research 2024年第2期15卷 211-221页

作者： Jia-li ZHANG Xiao-Meng HUANG yu-ze SUN Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModellingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China

Reliable monitoring and thorough spatiotemporal prediction of meteorological drought are crucial for early warning and decision-making regarding drought-related *** utilisation of multiscale methods is effective for a comprehensive evaluation of drought occurrence and progression,given the complex nature of meteorological ***,the nonlinear spatiotemporal features of meteorological droughts,influenced by various climatological,physical and environmental factors,pose significant challenges to integrated prediction that considers multiple indicators and time *** address these constraints,we introduce an innovative deep learning framework based on the shifted window transformer,designed for executing spatiotemporal prediction of meteorological drought across multiple *** formulate four prediction indicators using the standardized precipitation index and the standard precipitation evaporation index as core methods for drought definition using the ERA5 reanalysis *** indicators span time scales of approximately 30 d and one ***-term indicators capture more anomalous variations,whereas long-term indicators attain comparatively higher accuracy in predicting future *** focus on the East Asian region,notable for its diverse climate conditions and intricate terrains,to validate the model's efficacy in addressing the complexities of nonlinear spatiotemporal *** model's performance is evaluated from diverse spatiotemporal viewpoints,and practical application values are analysed by representative drought *** results substantiate the effectiveness of our proposed model in providing accurate multiscale predictions and capturing the spatiotemporal evolution characteristics of *** of the four drought indicators accurately delineates specific facets of the meteorological drought ***,three representative drought events,namely flash drought,sustained drought and severe drought,

关键词： Meteorological drought Spatiotemporal prediction Multiscale Swim transformer Deep learning

Compressive sensing SAR range compression with chirp scaling principle

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Science China(Information Sciences) 2012年第10期55卷 2292-2300页

作者： XIAO Peng,yu ze & li ChunSheng School of Electronics and Information Engineering,Beihang University,Beijing 100191,China School of Electronics and Information Engineering Beihang University Beijing China

Compressive sensing(CS) techniques offer a framework for the detection and allocation of sparse signal with a reduced number of *** paper proposes a novel SAR range compression,namely compressive sensing with chirp scaling(CS-CS),achieving the same range resolution as conventional SAR approach,while using fewer range *** order to realize accurate range cell migration correction(RCMC),chirp scaling principle is used to construct reference matrix for compressive sensing ***,error diagrams are designed for measurement of the performance of CS-CS,and some experiments of using real data are performed to deal with the errors caused by three conditions:SNR,sparsity and sampling.

关键词： synthetic aperture radar compressive sensing range cell migration correction error radar signal processing

Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron

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China Foundry 2024年第1期21卷 91-100页

作者： De-quan Shi ze-yu liu Gui-li Gao Yi-cheng Feng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Chemical Engineering Harbin University of Science&TechnologyHarbin 150040China School of Mechanical and Energy Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China

Thermal analysis plays a key role in the online inspection of molten iron *** solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten *** this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were *** results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an *** temperature at final solidification point TEShas little *** FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher *** to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these *** time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt.

关键词： FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron

A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun li Ming-Yi Wu Xu Han Si-yuan He ze-yu lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation