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添加复合稀释剂的低爆速乳化炸药的制备及性能

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工程爆破 2024年第2期30卷 132-139页

作者：何志伟李志远周汉红岳嘉伟张功震程维卢朝喜安徽理工大学化工与爆破学院安徽淮南232001 武汉市公安局治安管理局武汉430077 山东北方民爆器材有限公司山东淄博255208

以玻璃微球和滑石粉共同作为稀释剂制备一种低爆速乳化炸药。观察不同质量分数的玻璃微球和滑石粉对乳化炸药形貌的影响,并对乳化炸药的爆速、猛度、空中爆炸冲击波压力及储存稳定性进行测试。实验结果表明,随着滑石粉质量分数的增加,... 详细信息

以玻璃微球和滑石粉共同作为稀释剂制备一种低爆速乳化炸药。观察不同质量分数的玻璃微球和滑石粉对乳化炸药形貌的影响,并对乳化炸药的爆速、猛度、空中爆炸冲击波压力及储存稳定性进行测试。实验结果表明,随着滑石粉质量分数的增加,乳化炸药的形貌由乳胶状逐渐向颗粒状转化,爆速呈线性下降,对玻璃微球质量分数为5%、10%、15%的乳化炸药,测得最低爆速分别为3440、2740、2188 m/s。而随着滑石粉质量分数的增加,猛度、空中爆炸冲击波峰值超压均呈非线性下降,当滑石粉控制在一定量时,冲击波正压作用时间变化不大,乳化炸药储存稳定性较好。这种低爆速乳化炸药成本低廉、爆轰性能可调、储存稳定性好,具有较好的实用性。

关键词：低爆速乳化炸药玻璃微球滑石粉爆轰性能储存稳定性

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： wei-zhi Luo Mu he Liang Xia Qi-Chang he State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Investigation on Effects of Vertical Degree of Freedom on Gap Resonance Between Two Side-by-Side Boxes Under Wave Actions

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China Ocean Engineering 2022年第3期36卷 403-412页

作者： he zhi-wei GAO Jun-liang SHI Hua-bin ZANG Jun CheN Hong-zhou LIU Qian School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of MacaoMacao 999078China Centre for Infrastructure Geotechnical and Water Engineering(IGWE)Department of Architecture and Civil Engi-neeringUniversity of BathBA27AYUK School of Civil Engineering and Architecture Northeast Electric Power UniversityJilin 132012China

The possible wave resonance in the narrow gap formed by the parallel arrangement of ships will lead to the sharp increase of wave loads and the rapid growth of motion *** fluid resonance inside a narrow gap between two side-by-side boxes is investigated numerically based on an open-source CFD package,*** upstream box remains fixed,while the downstream box is allowed to heave freely under wave *** work aims to examine the influence of the motion of the downstream box on the fluid resonant behaviors inside the *** hydrodynamic behaviors considered include the wave height inside the gap,the heave displacement,and the reflection,transmission,and energy loss *** et al.(2021)reported the influence of the motion of the upstream box on gap resonant *** comparative study,some results of Gao et al.(2021)are also presented in this *** is found that the heave motion of any box in the two-box system leads to a smaller resonant wave height amplification and a larger fluid resonance *** frequency at which the maximum heave displacement of the downstream box occurs is less than the fluid resonant *** heave motion of any box in the two-box system results in a larger reflection coefficient and a smaller energy loss coefficient.

关键词： gap resonance wave height amplification heave motion OpenFOAM

基于Vpython的黏滞阻力作用下的物体运动仿真模拟

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大学物理 2024年第7期43卷 63-68,84页

作者：曲浩然刘玉颖赵志超赵云何志巍中国农业大学工学院机械工程系北京100083 中国农业大学理学院应用物理系北京100083 中国农业大学本科生院北京100083

大学物理教学中,黏滞阻力和终极速度是牛顿运动定律应用中很重要的概念内容.本文中我们首先对黏滞阻力和终极速度知识点进行比较与分析,进而应用Vpython软件对黏滞阻力作用下多种物体(蒲公英的种子、篮球、神舟飞船)的运动进行了仿真模... 详细信息

大学物理教学中,黏滞阻力和终极速度是牛顿运动定律应用中很重要的概念内容.本文中我们首先对黏滞阻力和终极速度知识点进行比较与分析,进而应用Vpython软件对黏滞阻力作用下多种物体(蒲公英的种子、篮球、神舟飞船)的运动进行了仿真模拟;有趣的是,在恒定质量基础上,我们还研究了变质量物体在黏滞阻力作用下的运动,例如对空中下落的质量不断变化的雨滴进行了理论分析和仿真模拟,结果表明:变质量的雨滴会趋近于一个终极速度,雨滴的半径大小不同、终极速度也不同;仿真模拟深化了对课本知识的理解.

关键词：黏滞阻力终极速度牛顿第二定律 Vpython

Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence

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Chinese Journal of Polymer Science 2024年第2期42卷 176-187,I0006页

作者： zhi Zou Xiang Xu Hai-Tao Zhao Jian-Nan Cheng wei-wei he Li-Fen Zhang Zhen-Ping Cheng Suzhou key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of JiangsuSoochow UniversitySuzhou215123China

Temperature-responsive polymers have garnered significant attention due to their ability to respond to external *** this work,dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization(RAFT)polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine(SBMA) and N-isopropyl acrylamide(NIPAAm) as *** thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate(BN) or hydrophilic monomer acrylic acid(AA),adjusting concentration or pH,or varying the degree of polymerization of the block chain *** cloud points of the copolymers are determined by UV-Vis spectrophotometry,and these copolymers exhibit both controlled upper and lower critical solu bility temperatures(LCST and UCST) in aqueous *** study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation *** is very interesting that the introduction of poly-acrylic acid(PAA) segments in the middle of di-block copolymer PSBMA_(55)-b-PNIPAAm_(80) to form PSBMA_(55)-b-PAA_(x)-b-PNIPAAm_(80) results in a reversal of temperature-responsive behaviors from 'U'(LCST UCST) type,while the copolymer PSBMA_(55)-b-P(NIPAAm_(80)-co-AA_(x)) *** work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials.

关键词： Temperature responsive polymers High critical solubility temperature(UCST) Low critical solubility temperature(LCST) Block copolymers

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： zhi-Lin Shen Jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： he-xiang Wu Jia Qu Lin-zhi Wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

OsPDR20 is an ABCG metal transporter regulating cadmium accumulation in rice

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Journal of Environmental Sciences 2024年第2期136卷 21-34页

作者： he Li Chao Li Di Sun zhi Min Yang Department of Biochemistry and Molecular Biology College of Life SciencesNanjing Agricultural UniversityNanjing 210095China

Cadmium(Cd)is a non-essential toxic heavy metal,seriously posing high environmental risks to human *** genetic resources relevant to functional genes is important for understanding the metal absorption and accumulation in crops and bioremediation of Cd-polluted *** study investigated a functionally uncharacterized ATP binding cassette transporter G family(ABCG)gene encoding a Pleiotropic Drug Resistance 20(PDR20)type metal transporter which is localized to the plasma membrane of ***20 was transcriptionally expressed in almost all tissues and organs in lifespan and was strongly induced in roots and shoots of young rice under Cd *** expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cellular tolerance with less Cd *** of OsPDR20 by RNA interference(RNAi)moderately attenuated root/shoot elongation and biomass,with reduced chlorophylls in rice grown under hydroponic medium with 2 and 10μmol/L Cd,but led to more Cd accumulation.A field trial of rice grown in a realistic Cd-contaminated soil(0.40 mg/kg)showed that RNAi plants growth and development were also compromised compared to wild-type(WT),with smaller panicles and lower spikelet fertility but little effect on yield of ***,OsPDR20 suppression resulted in unexpectedly higher levels of Cd accumulation in rice straw including lower leaves and culm and *** results suggest that OsPDR20 is actively involved in Cd accumulation and homeostasis in rice *** increased Cd accumulation in the RNAi plants has the potential application in phytoremediation of Cd-polluted wetland soils.

关键词： Rice ABCG transporter Cadmium accumulation Phytoremediation

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng he Hai-Bo Cheng Peng Zeng Chuan-zhi Zang Qing-wei Dong Guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix