检索结果-南通市图书馆

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

在线全文

学校读者我要写书评

暂无评论

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

HZSM-5表面酸碱中心的表征及对芥子气的催化降解性能

在线全文

学校读者我要写书评

暂无评论

石油学报（石油加工） 2008年第B10期24卷 116-119,123页

作者：汤海荣程振兴解放军防化指挥工程学院北京102205

采用Hammett指示剂法、表面零电荷点ZPC（Zeropointofcharge）和CO2（NH3）TPD法对HZSM-5表面酸碱中心的强度和数量进行了表征，研究了HZSM-5对芥子气（HD）催化降解，并采用GC-MS、GC—FPD等手段检测了催化降解的产物。结果表明，HZSM-... 详细信息

采用Hammett指示剂法、表面零电荷点ZPC（Zeropointofcharge）和CO2（NH3）TPD法对HZSM-5表面酸碱中心的强度和数量进行了表征，研究了HZSM-5对芥子气（HD）催化降解，并采用GC-MS、GC—FPD等手段检测了催化降解的产物。结果表明，HZSM-5的pKa值为-3．0～-5．6，为典型的固体酸性氧化物。在25℃空气（20％～30％RH）条件下，HZSM-5能降解HD液滴，反应的假-级速率常数为5．3×10^-6s^-1。HD液滴于HZSM-5表面的降解产物主要为2-chloroethyl2-hydroxyethylsulfide（cH）和1，4-dithiane，表明HD液滴在酸中心的作用下主要发生加成-消去反应。

关键词： HZSM-5 芥子气降解酸碱中心 TPD

Rapid development of double-hit mRNA antibody cocktail against orthopoxviruses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第4期9卷 1768-1776页

作者： Hang Chi Suo-Qun Zhao Ru-Yi Chen xing-xing Suo Rong-Rong Zhang Wen-Hui Yang Dong-Sheng Zhou Min Fang Bo Ying Yong-Qiang Deng cheng-Feng Qin State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyAMMS100071BeijingChina College of Life Sciences Inner Mongolia Agricultural UniversityHohhot010018Inner MongoliaChina School of Life Sciences Henan UniversityKaifeng475004HenanChina Suzhou Abogen Biosciences Co. LtdSuzhou215123JiangsuChina Research Unit of Discovery and Tracing of Natural Focus Diseases Chinese Academy of Medical Sciences100071BeijingChina

The Orthopoxvirus genus,especially variola virus(VARV),monkeypox virus(MPXV),remains a significant public health threat *** development of therapeutic antibodies against orthopoxviruses is largely hampered by the high cost of antibody engineering and manufacturing ***-encoded antibodies have emerged as a powerful and universal platform for rapid antibody ***,by using the established lipid nanoparticle(LNP)-encapsulated mRNA platform,we constructed four mRNA combinations that encode monoclonal antibodies with broad neutralization activities against *** vivo characterization demonstrated that a single intravenous injection of each LNP-encapsulated mRNA antibody in mice resulted in the rapid production of neutralizing *** importantly,mRNA antibody treatments showed significant protection from weight loss and mortality in the vaccinia virus(VACV)lethal challenge mouse model,and a unique mRNA antibody cocktail,Mix2a,exhibited superior in vivo protection by targeting both intracellular mature virus(IMV)-form and extracellular enveloped virus(EEV)-form *** summary,our results demonstrate the proof-of-concept production of orthopoxvirus antibodies via the LNP-mRNA platform,highlighting the great potential of tailored mRNA antibody combinations as a universal strategy to combat orthopoxvirus as well as otheremerging viruses.

关键词： proof universal neutral

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing Wang Ling Wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

Improved genome annotation of Brassica oleracea highlights the importance of alternative splicing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Horticultural Plant Journal 2024年第4期10卷 961-970页

作者： Yinqing Yang Lei Zhang Qi Tang Lingkui Zhang xing Li Shumin Chen Kang Zhang Ying Li Xilin Hou Feng cheng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing 210095China State Key Laboratory of Vegetable Biobreeding Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture and Rural AffairsSino-Dutch Joint Laboratory of Horticultural GenomicsBeijing 100081China

Brassica oleracea has been developed into many important crops,including cabbage,kale,cauliflower,broccoli and so *** genome and gene annotation of cabbage(cultivar JZS),a representative morphotype of ***,has been widely used as a common reference in biological *** its genome assembly has been updated twice,the current gene annotation still lacks information on untranslated regions(UTRs)and alternative splicing(AS).Here,we constructed a high-quality gene annotation(JZSv3)using a full-length transcriptome acquired by nanopore sequencing,yielding a total of 59452 genes and 75684 ***,we re-analyzed the previously reported transcriptome data related to the development of different tissues and cold response using JZSv3 as a reference,and found that 3843 out of 11908 differentially expressed genes(DEGs)underwent AS during the development of different tissues and 309 out of 903 cold-related genes underwent AS in response to cold ***,we also identified many AS genes,including BolLHCB5 and BolHSP70,that displayed distinct expression patterns within variant transcripts of the same gene,highlighting the importance of JZSv3 as a pivotal reference for AS ***,JZSv3 provides a valuable resource for exploring gene function,especially for obtaining a deeper understanding of AS regulation mechanisms.

关键词： Brassica oleracea Oxford nanopore technologies Gene annotation Alternative splicing

Structural regulation of coal-derived hard carbon anode for sodium-ion batteries via pre-oxidation

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2585-2596页

作者： Meng-Yuan Su Kai-Yang Zhang Edison Huixiang Ang Xue-Li Zhang Yan-Ning Liu Jia-Lin Yang zhen-Yi Gu Faaz A.Butt xing-Long Wu Faculty of Chemistry Northeast Normal UniversityChangchun 130024China MOE Key Laboratory for UV Light-Emiting Materials and Technology.Northeast Normal University.Ministry of Education Changchun 130024China Natural Sciences and Science Education National Institute of EducationNanyang Technological UniversitySingapore 637616Singapore Materials Engineering Department NED University of Engineering and TechnologyKarachi 75300Pakistan

Hard carbon(HC)is broadly recognized as an exceptionally prospective candidate for the anodes of sodium-ion batteries(SIBs),but their practical implementation faces substantial limitations linked to precursor factors,such as reduced carbon yield and increased ***,a cost-effective approach is proposed to prepare a coal-derived HC anode with simple pre-oxidation followed by a post-carbonization process which effectively expands the d_(002)layer spacing,generates closed pores and increases defect *** these modifications,the resulting HC anode attains a delicate equilibrium between plateau capacity and sloping capacity,showcasing a remarkable reversible capacity of 306.3 mAh·g^(-1)at 0.03 A·g^(-1).Furthermore,the produ ced HC exhibits fast reaction kinetics and exceptional rate performance,achieving a capacity of 289 mAh·g^(-1)at 0.1 A·g^(-1),equivalent to~94.5%of that at 0.03 A·g^(-1).When implemented in a full cell configuration,the impressive electrochemical performance is evident,with a notable energy density of 410.6 Wh·kg^(-1)(based on cathode mass).In short,we provide a straightforward yet efficient method for regulating coal-derived HC,which is crucial for the widespread use of SIBs anodes.

关键词： Sodium-ion batteries Hard carbon Anode Coal Pre-oxidation

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Research on the influences of motion characteristics of jetting projectile charge under water

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Adverse Effects of Opioid Analgesics in Osteoarthritis Treatment:A Global Meta-Analysis,2000-2022

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第25期6卷 589-596,I0001-I0012页

作者： Heng Jiang xing xing He Zhu Tuo Dong School of Public Health Harbin Medical UniversityHarbin CityHeilongjiang ProvinceChina School of Public Health Peking UniversityBeijingChina

Osteoarthritis(OA)treatment commonly depends on nonsteroidal anti-inflammatory drugs and opioid ***,the clinical use of opioids is controversial due to their adverse effects and addiction *** study,drawing on 24 randomized controlled trials(RCTs)with a total of 9,586 patients,thoroughly explored the various side effects associated with opioid use in OA *** results provide additional insight into the non-addictive risks of opioids and may assist clinicians in their judicious use,potentially fostering the advancement of safer treatment *** reducing the risks of misuse and addiction,public health and safety can be enhanced.

关键词： potential thoroughly insight