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组合-填充药型罩成型及侵彻靶板数值模拟

火工品 2025年第1期 44-50页

作者：张卿尚王志军伊建亚何卓朗太忻贺磊中北大学机电工程学院山西太原030051

针对聚能射流侵彻披挂爆炸反应装甲坦克顶部装甲的高效毁伤问题,提出了一种新型的组合-填充药型罩结构。采用非线性动力学分析软件AUTODYN-2D对射流形成和侵彻靶板过程进行了数值模拟,并分析了填充物材料和起爆方式对射流成型的影响以... 详细信息

针对聚能射流侵彻披挂爆炸反应装甲坦克顶部装甲的高效毁伤问题,提出了一种新型的组合-填充药型罩结构。采用非线性动力学分析软件AUTODYN-2D对射流形成和侵彻靶板过程进行了数值模拟,并分析了填充物材料和起爆方式对射流成型的影响以及炸高对侵彻性能的影响。研究结果表明:所提出的组合-填充药型罩可以形成首尾相连的两级串联射流,填充物采用铝和特氟龙时射流成型效果较好,但铝成型更加稳定;点环起爆形成的射流动能比单独点起爆形成的前级射流动能提高67.06%,后级射流动能提高29.51%;在炸高区间为2~6 CD(装药直径)时,成型射流均可以侵彻披挂爆炸反应装甲的坦克顶甲,并保持一定的剩余头部速度,且最佳炸高为5 CD。本研究对反披挂爆炸反应装甲坦克顶甲的新结构药型罩设计具有参考意义。

关键词：药型罩爆炸反应装甲填充物起爆方式炸高数值模拟

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Damage evaluation of reinforced concrete frame based on a combined fiber beam model

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Science China(Physics,Mechanics & Astronomy) 2014年第4期57卷 723-730页

作者： shang Bing LIU ZhanLi ZHUANG zhuo Applied Mechanics Lab School of Aerospace Tsinghua University

In order to analyze and simulate the impact collapse or seismic response of the reinforced concrete(RC)structures,a combined fiber beam model is proposed by dividing the cross section of RC beam into concrete fiber and steel *** stress-strain relationship of concrete fiber is based on a model proposed by concrete codes for concrete *** stress-strain behavior of steel fiber is based on a model suggested by *** constitutive models are implemented into a general finite element program ABAQUS through the user defined subroutines to provide effective computational tools for the inelastic analysis of RC frame *** fiber model proposed in this paper is validated by comparing with experiment data of the RC column under cyclical lateral *** damage evolution of a three-dimension frame subjected to impact loading is also investigated.

关键词： RC frame structure fiber model beam-column element dynamic response impact

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： ya-Ping Shao zhuo-Min Chi Yong-Min Liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

The Structure and Sequence Analysis of TLR4 Gene in Cattle

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Agricultural Sciences in China 2009年第5期8卷 632-637页

作者： WANG Xing-ping LUORENG zhuo-ma XU shang-zhong GAO Xue LI Jun-ya REN Hong-yan CHEN Jin-bao Department of Life Sciences and Technology Xinxiang Medicine University Xinxiang 453003 P.R. China Laboratory of Molecular Biology and Bovine Breeding Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China

Toll-like receptor 4 （TLR4） is essential for initiating the innate response to lipopolysaccharide （LPS） from Gram-negative bacteria by acting as a signal transducting receptor. In order to help in investigating TLR4 as a candidate disease-resistance gene in cows, we isolated the cDNA （GenBank accession no. DQ839566） by RT-PCR and rapid amplification of cDNA ends （RACE） experiments and analyzed the sequence characters by bioinformatics. The results showed that cattle TLR4 gene about 3 739 bp contains an open reading frame of 2 526 bp encoded 841 amino acids （aa）, 470 bp 5′ untranslated region （UTR）, and 743 bp 3′ UTR. Tissue expression profile by RT-PCR indicated that TLR4 gene expresses in mammary glands, liver, muscle, duodenum, fats, uterus, kidneys, hearts, lungs, pancreas, and ovary. TLR4 protein domain predicted by bioinformatics consists of signal peptide, transmembrane helices domain, 3 sorts of leucine-rich repeat domains （LRR, LRR-TYP, and LRRCT）, and a toll-interleukinl-resistance domain （TIR）. Leucine-rich repeat domains were related with recognizing a broad of pathogen-associated molecular patterns （PAMP） from pathogen, and TIR domain for downstream signaling transduction was most conservative （98% identify） than other domains after alignment of protein from ovine, porcine, human, and mouse. In addition, a 470 bp 5′-flanking region sequence was amplified by PCR, and 15 putative DNA binding sites were predicted, but this sequence lacks TATA box, CCAAT character, and GC-rich regions.

关键词： cattle toll-like receptor 4 LRR domain TIR domain DNA binding site

In situ TiN-reinforced CoCr2FeNiTi(0.5) high-entropy alloy composite coating fabricated by laser cladding

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Rare Metals 2020年第10期39卷 1190-1195页

作者： ya-Xiong Guo Qi-Bin Liu Xiao-Juan shang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Materials Structure and Strength Guiyang 550025China

The fcc structural CoCr2 FeNiTi(0.5) high-entropy alloy(HEA) composite coating with TiN particles reinforced was acquired by laser cladding on the commercial904 L stainless *** results show that phase structure is mainly composed of fcc solid solution and TiN *** coating exhibits excellent structural stability below850℃.The microstructure consists of irregular dendrite and TiN *** electron microscopy(TEM) results reveal that the close-packed plane of fcc phase is(111) with interplanar spacing of ~ 0.208 *** interface between TiN and fcc matrix is *** the angle of boundary between dendrite and matrix is ~ 65°.The hardness and corrosion resistance of coating have much improvement compared with those of substrate.

关键词： TiN particle reinforced High-entropy alloy Semi-coherent interface Laser cladding

Coupling Relationship between Shelf-Edge Trajectories and Slope Morphology and Its Implications for Deep-Water Oil and Gas Exploration: A Case Study from the Passive Continental Margin, East Africa

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Journal of Earth Science 2020年第4期31卷 820-833页

作者： Mengtian Gao shang Xu Haiteng zhuo Yuxuan Wang Shaobo Wu Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Both the shelf-edge trajectories and slope morphology are indicative of deep-water sedimentation, but previous studies are relatively independent from each other in the two dimensions. An integrated investigation can enhance the understanding of deep-water sedimentary systems and enrich reservoir prediction methods. Based on the bathymetry data and seismic data published, this study identified ten slope areas at the continental margin of East Africa and classified the clinoforms into three types: concave-up, sigmoidal and planar. Combined with the distribution of main modern rivers in East Africa, nine modern source-to-sink systems were identified and the catchment area is positively correlated with the size of the shelf-edge delta. It is found that the slope morphology of East Africa is closely related to the geological setting, sediment supply and sediment transport pathway in submarine canyon of passive continental margin. When the sediment supply is stable, the concave-up slopes are dominated by the river-associated and shelf-incising canyons and the sigmoidal slopes are determined by the headless canyons. There exists a strong coupling relationship between the shelf-edge trajectories and slope morphology. In general, concave-up slopes correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories and high-quality reservoirs developed on the basin floor under the influence of river-associated and shelf-incising canyons which have bright prospects for oil and gas exploration. Additionally, sigmoidal slopes usually correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories at times of relative sea-level fall and the reservoirs mostly developed on the upper slope under the influence of headless canyons. Moreover, the planar slopes correspond to high-angle ascending trend trajectories which are hardly potential for exploration. The coupling model built in this study will provide an insight for oil and gas e

关键词： shelf-edge trajectories slope morphology source to sink deep water sediment East Africa continental margin

Multiplexed intracellular detection based on dual-excitation/dualemission upconversion nanoprobes

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Nano Research 2020年第7期13卷 1955-1961页

作者： Jianxi Ke Shan Lu zhuo Li Xiaoying shang Xingjun Li Renfu Li Datao Tu zhuo Chen Xueyuan Chen CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Multiplexed intracellular detection is desirable in biomedical sciences for its higher eficiency and accuracy compared to the single-analyte ***,it is very challenging to construct nanoprobes that possess multiple fluorescent signals to recognize the different intracellular species ***,we proposed a novel dual-excitation/dual-emission upconversion strategy for multiplexed detection through the design of upconversion nanoparticles(UCNP)loaded with two dyes for sensitization and quenching of the upconversion luminescence(UCL),*** on the two independent energy transfer processes of near-infrared(NIR)dye IR845 to UCNP and UCNP to visible dye PAPS-Zn,CIO-and Zn2+were simultaneously detected with a limit of detection(LOD)of41.4 and 10.5 nM,*** tilizing a purpose built 830/980 nm dual-laser confocal microscope,both intrinsic and exogenous CIO and Zn2+in live MCF-7 cells have been accurately *** dual-excitation/dual-emission ratiometric UCL detection mode enables not only monitoring multiple intracellular analytes but also eliminating the detection deviation caused by inhomogeneous probe distribution in *** modulation of NIR dye and visible dye with other reactive groups,the nanoprobes can be extended to analyze various intraellular species,which provides a promising tool to study the biological activities in live cells and diagnose diseases.

关键词： upconversion nanoparticles energy transfer dual-excitation dye sensitization ratiometric probe multiplexed detection

RF power and I/Q imbalance calibration in B3G/4G MIMO-OFDM systems

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 89-93,124页

作者： LI ya-zhuo ZHOU Ming-yu ZHANG Ping Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Radio frequency （RF） front-end nonidealities in multi-input and multi-output （MIMO） systems are more serious than in single-input and single-output systems and must be calibrated. According to the effects of RF power and in-phase/quadrature-phase （I/Q） imbalance, calibration methods for multi-input and multi-output-orthogonal frequency division multiplexing （MIMC-OFDM） systems in transmitter and interference in receiver are improved, respectively, in this article Furthermore, a calibration scheme including I/Q imbalance errors and amplitude variations is proposed and implemented in the B3G/4G time division duplex communication system. Simulation results show that the calibration algorithms are feasible, and the bit error rate （BER） performances for MIMO-OFDM systems are improved after calibrations.

关键词： calibration, B3G/4G MIMO-OFDM, front-end, I/Q imbalance

Distributed reinforcement learning to coordinate current sharing and voltage restoration for islanded DC microgrid

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Journal of Modern Power Systems and Clean Energy 2018年第2期6卷 364-374页

作者： Zifa LIU ya LUO Ranqun zhuo Xianlin JIN North China Electric Power University Guohua Energy Investment Co. Ltd.

A novel distributed reinforcement learning(DRL)strategy is proposed in this study to coordinate current sharing and voltage restoration in an islanded DC ***, a reward function considering both equal proportional current sharing and cooperative voltage restoration is defined for each local agent. The global reward of the whole DC microgrid which is the sum of the local rewards is regarged as the optimization objective for DRL. Secondly,by using the distributed consensus method, the predefined pinning consensus value that will maximize the global reward is obtained. An adaptive updating method is proposed to ensure stability of the above pinning consensus method under uncertain communication. Finally, the proposed DRL is implemented along with the synchronization seeking process of the pinning reward, to maximize the global reward and achieve an optimal solution for a DC microgrid. Simulation studies with a typical DC microgrid demonstrate that the proposed DRL is computationally efficient and able toprovide an optimal solution even when the communication topology changes.

关键词： Distributed reinforcement learning(DRL) Distributed information discovery DC microgrid Local reward function