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Effect of non-vacuum storage condition on minimum explosible concentration of aluminum dust 被引量:3
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作者 ZHANG Shi-an ZHANG Lu-gang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第3期219-222,共4页
Non-vacuum storage condition has a great impact on the explosion characteristics of aluminum powders. In this paper, vacuum-packed flake and globular aluminum powders stored in a dryer after opening the vacuum package... Non-vacuum storage condition has a great impact on the explosion characteristics of aluminum powders. In this paper, vacuum-packed flake and globular aluminum powders stored in a dryer after opening the vacuum package are selected as the experimental samples, and a 20 L spherical explosion device is chosen to test the minimum explosible concentration (MEC) values of aluminum dusts under different storage time. The results show that the MEC values of two types of unoxidized aluminum powders are 30 g/m^3. The MEC values of flake and globular aluminum powders firstly go up with the increase of storage time in the dryer and then reach the maximum values of 50 g/m^3 and 60 g/m^3 at respective storage time until finally they stabilize gradually. The main reason is that the oxidation rate is faster owing to the bigger specific surface area of globular aluminum powders. Hence, the storage time has more significant effect on the MEC of globular aluminum powder than that of flake aluminum powder. After a period of time, the outer surface is oxidized to generate a layer of film, which prevents the further oxidation of aluminum powder, resulting in the temporary stability of MEC. 展开更多
关键词 storage condition oxidation rate aluminum powders minimum explosible concentration (MEC)
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进化的“寒武纪生命大爆发”——(一)一个让达尔文“挠头”的现象
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作者 郭建崴 《化石》 2025年第3期31-33,共3页
“寒武纪生命大爆发”(Cambrian Explosion)这一术语,是英国古生物学家布雷希尔(M.D.Brasier)在1979年正式提出的,其最新含义是指“距今5.41亿-5.2亿年的寒武纪早期生物多样性突然增加,几乎主要的现生后生动物门及一些已灭绝的动物线系... “寒武纪生命大爆发”(Cambrian Explosion)这一术语,是英国古生物学家布雷希尔(M.D.Brasier)在1979年正式提出的,其最新含义是指“距今5.41亿-5.2亿年的寒武纪早期生物多样性突然增加,几乎主要的现生后生动物门及一些已灭绝的动物线系类群均出现或起源于这一时期,显示在漫长的生物进化历史中寒武纪早期是最重要的时期之一,动物(尤其是在门一级的分类阶元)的辐射进化呈爆发性。” 展开更多
关键词 寒武纪生命大爆发 Cambrian Explosion
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Preparation and Performance of Large-Size Seamless Zirconium-Titanium-Steel Composite Plate 被引量:1
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作者 Wu Jiangtao Wang Ding +7 位作者 Huang Xingli Zou Juntao Zhang Penghui Gao Ruibo Yang Huan Zhang Tao Ren Qianyu Wei Yong 《稀有金属材料与工程》 北大核心 2025年第2期319-326,共8页
Zirconium-titanium-steel composite plate with the size of 2500 mm×7800 mm×(3+0.7+22)mm was prepared by explosive welding+rolling method,and its properties were analyzed by ultrasonic nondestructive testing,p... Zirconium-titanium-steel composite plate with the size of 2500 mm×7800 mm×(3+0.7+22)mm was prepared by explosive welding+rolling method,and its properties were analyzed by ultrasonic nondestructive testing,phased array waveform shape,interface structure shape,electronic scanning,and mechanical property testing.Results show that the rolling temperature of zirconiumtitanium complex should be controlled at 760°C,and the rolling reduction of each pass should be controlled at 10%–25%.The explosive velocity to prepare zirconium-titanium-steel composite plates should be controlled at 2450–2500 m/s,the density should be 0.78 g/cm3,the stand-off height should be 12 mm,and the explosive height of Zone A and Zone B should be 45–50 mm.Explosive welding combined with rolling method reduces the impact of explosive welding and multiple heat treatment on material properties.Meanwhile,the problems of surface wrinkling and cracking,which occur during the preparation process of large-sized zirconiumtitanium-steel composite plate,can be solved. 展开更多
关键词 large-size seamless zirconium-titanium-steel composite plate explosive welding+rolling phased array interface structure
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Microstructure Analysis of TC4/Al 6063/Al 7075 Explosive Welded Composite Plate via Multi-scale Simulation and Experiment 被引量:1
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作者 Zhou Jianan Luo Ning +3 位作者 Liang Hanliang Chen Jinhua Liu Zhibing Zhou Xiaohong 《稀有金属材料与工程》 北大核心 2025年第1期27-38,共12页
Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer ... Because of the challenge of compounding lightweight,high-strength Ti/Al alloys due to their considerable disparity in properties,Al 6063 as intermediate layer was proposed to fabricate TC4/Al 6063/Al 7075 three-layer composite plate by explosive welding.The microscopic properties of each bonding interface were elucidated through field emission scanning electron microscope and electron backscattered diffraction(EBSD).A methodology combining finite element method-smoothed particle hydrodynamics(FEM-SPH)and molecular dynamics(MD)was proposed for the analysis of the forming and evolution characteristics of explosive welding interfaces at multi-scale.The results demonstrate that the bonding interface morphologies of TC4/Al 6063 and Al 6063/Al 7075 exhibit a flat and wavy configuration,without discernible defects or cracks.The phenomenon of grain refinement is observed in the vicinity of the two bonding interfaces.Furthermore,the degree of plastic deformation of TC4 and Al 7075 is more pronounced than that of Al 6063 in the intermediate layer.The interface morphology characteristics obtained by FEM-SPH simulation exhibit a high degree of similarity to the experimental results.MD simulations reveal that the diffusion of interfacial elements predominantly occurs during the unloading phase,and the simulated thickness of interfacial diffusion aligns well with experimental outcomes.The introduction of intermediate layer in the explosive welding process can effectively produce high-quality titanium/aluminum alloy composite plates.Furthermore,this approach offers a multi-scale simulation strategy for the study of explosive welding bonding interfaces. 展开更多
关键词 TC4/Al 6063/Al 7075 composite plate explosive welding microstructure analysis multi-scale simulation
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Review of Research on Underwater Explosions Related to Ship Damage and Stability 被引量:1
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作者 Ruiyao Zhang Wei Xiao +1 位作者 Xiongliang Yao Xiaochao Zou 《哈尔滨工程大学学报(英文版)》 2025年第2期285-300,共16页
Researchers have achieved notable advancements over the years in exploring ship damage and stability resulting from underwater explosions(UNDEX).However,numerous challenges and open questions remain in this field.In t... Researchers have achieved notable advancements over the years in exploring ship damage and stability resulting from underwater explosions(UNDEX).However,numerous challenges and open questions remain in this field.In this study,the research progress of UNDEX load is first reviewed,which covers the explosion load during the shock wave and bubble pulsation stages.Subsequently,the research progress of ship damage caused by UNDEX is reviewed from two aspects:contact explosion and noncontact explosion.Finally,the research progress of ship navigation stability caused by UNDEX is reviewed from three aspects:natural factors,ship’s internal factors,and explosion factors.Analysis reveals that most existing research has focused on the damage to displacement ships caused by UNDEX.Meanwhile,less attention has been paid to the damage and stability of non-displacement ships caused by UNDEX,which are worthy of discussion. 展开更多
关键词 Underwater explosion Load characteristics Structural damage STABILITY Non-displacement ships
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Experimental Study on the Coupling Dynamics of Metal Jet,Waves,and Bubble During Underwater Explosion of a Shaped Charge 被引量:1
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作者 Yu Tian A-Man Zhang +1 位作者 Liu-Yi Xu Fu-Ren Ming 《Engineering》 2025年第7期168-187,共20页
Unlike conventional spherical charges,a shaped charge generates not only a strong shock wave and a pulsating bubble,but also a high strain rate metal jet and a ballistic wave during the underwater explosion.They show ... Unlike conventional spherical charges,a shaped charge generates not only a strong shock wave and a pulsating bubble,but also a high strain rate metal jet and a ballistic wave during the underwater explosion.They show significant characteristic differences and couple each other.This paper designs and conducts experiments with shaped charges to analyze the complicated process.The effects of liner angle and weight of shaped charge on the characteristics of metal jets,waves,and bubbles are discussed.It is found that in underwater explosions,the shaped charge generates the metal jet accompanied by the ballistic wave.Then,the shock wave propagates and superimposes with the ballistic wave,and the generated bubble pulsates periodically.It is revealed that the maximum head velocity of the metal jet versus the liner angle a and length-to-diameter ratio k of the shaped charge follows the laws of 1/(α/180°)^(0.55)andλ^(0.16),respectively.The head shape and velocity of the metal jet determine the curvature and propagation speed of the initial ballistic wave,thus impacting the superposition time and region with the shock wave.Our findings also reveal that the metal jet carries away some explosion products,which hinders the bubble development,causing an inward depression of the bubble wall near the metal jet.Therefore,the maximum bubble radius and pulsation period are 5.2%and 3.9%smaller than the spherical charge with the same weight.In addition,the uneven axial energy distribution of the shaped charge leads to an oblique bubble jet formation. 展开更多
关键词 Shaped charge Underwater explosion Metal jet WAVES BUBBLE Coupling dynamics
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Study on cook-off characteristics and thermal safety venting area of RBOE charge 被引量:1
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作者 Kebin Zhang Wenbin Li +3 位作者 Changfang Zhao Zhifang Wei Shuxia Zhang Jin Li 《Defence Technology(防务技术)》 2025年第1期271-287,共17页
RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomp... RBOE is a new type of DNAN-based high-energy melt-cast mixed explosive,whose safety under thermal stimulation is significantly affected by heating conditions and venting area of the warhead.Based on the thermal decomposition reaction characteristics and combustion characteristics of each component of RBOE explosive,the cook-off calculation models of RBOE warhead before and after ignition were established.In addition,closed and vented warheads were designed,as well as fast and slow cook-off test devices.The cook-off characteristics and thermal safety venting area of RBOE warhead were extensively studied.The results showed that the closed RBOE warhead underwent deflagration reaction under both slow and fast cook-off conditions.The calculation result of the shell wall temperature before slow cookoff ignition response of the warhead was 454.06 K,with an error of+1.75%compared to the test result of462.15 K,and the temperature rise rate calculated was in good agreement with the test.The calculated ignition time of RBOE warhead under fast cook-off was 161 s,with an error of+8.8%compared to the test result of 148 s,which verified the accuracy of cook-off model of RBOE warhead before ignition.According to the cook-off calculation model of the warhead after ignition and cook-off test of the vented warhead,it was determined that the thermal safety venting area was 1124.61 mm^(2)for fast cook-off and 530.66 mm~2 for slow cook-off,effectively preventing the reaction of warhead above combustion.Therefore,this study provides a scientific basis for the thermal safety design and evaluation of insensitive warheads. 展开更多
关键词 RBOE explosive Cook-off model Temperature distribution Pressure growth Venting area
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Oscillation mechanism and predictive model of explosion load for natural gas in confined tube 被引量:1
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作者 Chengjun Yue Li Chen Linfeng Xu 《Defence Technology(防务技术)》 2025年第3期13-27,共15页
Gas explosion in confined space often leads to significant pressure oscillation.It is widely recognized that structural damage can be severe when the oscillation frequency of the load resonates with the natural vibrat... Gas explosion in confined space often leads to significant pressure oscillation.It is widely recognized that structural damage can be severe when the oscillation frequency of the load resonates with the natural vibration frequency of the structure.To reveal the oscillation mechanism of gas explosion load,the experiment of gas explosion was conducted in a large-scale confined tube with the length of 30 m,and the explosion process was numerically analyzed using FLACS.The results show that the essential cause of oscillation effect is the reflection of the pressure wave.In addition,due to the difference in the propagation path of the pressure wave,the load oscillation frequency at the middle position of the tunnel is twice that at the end position.The average sound velocity can be used to calculate the oscillation frequency of overpressure accurately,and the error is less than 15%.The instability of the flame surface and the increase of flame turbulence caused by the interaction between the pressure wave and the flame surface are the main contributors to the increase in overpressure and amplitude.The overpressure peaks calculated by the existing flame instability model and turbulence disturbance model are 31.7%and 34.7%lower than the numerical results,respectively.The turbulence factor model established in this work can describe the turbulence enhancement effect caused by flame instability and oscillatory load,and the difference between the theoretical and numerical results is only 4.6%.In the theoretical derivation of the overpressure model,an improved model of dynamic turbulence factor is established,which can describe the enhancement effect of turbulence factor caused by flame instability and self-turbulence.Based on the one-dimensional propagation theory of pressure wave,the oscillatory effect of the load is derived to calculate the frequency and amplitude of pressure oscillation.The average error of amplitude and frequency is less than 20%. 展开更多
关键词 Gas explosion Oscillatory load Oscillation frequency Turbulence factor
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Bubble Theory and its Applications in Underwater Explosion, Marine Cavitation, and Seismic Exploration 被引量:1
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作者 Runze Xu Shiping Wang +1 位作者 Hemant J.Sagar Haikun Wang 《哈尔滨工程大学学报(英文版)》 2025年第2期255-284,共30页
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee... Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields. 展开更多
关键词 Bubble theory Underwater explosion Marine cavitation Seismic exploration
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Surface-covering water significantly amplifies the explosion impulse of shallow buried explosives 被引量:1
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作者 Zhenyu Zhao Wenbo Gao +6 位作者 Jianwei Ren Zihan Lan Zhiyang Zhang Huiyao Gao Chao He Changye Ni Tianjian Lu 《Defence Technology(防务技术)》 2025年第6期156-172,共17页
While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and ... While the moisture content of soil affects significantly the blast impulse of shallow buried explosives,the role of surface-covering water(SCW)on soil in such blast impulse remains elusive.A combined experimental and numerical study has been carried out to characterize the effect of SCW on transferred impulse and loading magnitude of shallow buried explosives.Firstly,blast tests of shallow buried explosives were conducted,with and without the SCW,to quantitatively assess the blast loading impulse.Subsequently,finite element(FE)simulations were performed and validated against experimental measurement,with good agreement achieved.The validated FE model was then employed to predict the dynamic response of a fully-clamped metallic circular target,subjected to the explosive impact of shallow buried explosives with SCW,and explore the corresponding physical mechanisms.It was demonstrated that shallow buried explosives in saturated soil generate a greater impulse transferred towards the target relative to those in dry soil.The deformation displacement of the target plate is doubled.Increasing the height of SCW results in enhanced center peak deflection of the loaded target,accompanied by subsequent fall,due to the variation of deformation pattern of the loaded target from concentrated load to uniform load.Meanwhile,the presence of SCW increases the blast impulse transferred towards the target by three times.In addition,there exists a threshold value of the burial depth that maximizes the impact impulse.This threshold exhibits a strong sensitivity to SCW height,decreasing with increasing SCW height.An empirical formula for predicting threshold has been provided.Similar conclusions can be drawn for different explosive masses.The results provide technical guidance on blast loading intensity and its spatial distribution considering shallow buried explosives in coast-land battlefields,which can ultimately contribute to better protective designs. 展开更多
关键词 Shallow buried explosives Fluid-structure interaction Surface-covering water Impulse distribution
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Dynamic response of blast doors enhanced by enclosed-space TNT explosions: Experimental and numerical study 被引量:1
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作者 Chenwei Wu Guokai Zhang +3 位作者 Yong He Liwang Liu Ju Liu Xiaoning Yang 《Defence Technology(防务技术)》 2025年第6期173-186,共14页
The afterburning of TNT and structural constraints in confined spaces significantly amplify the blast load,leading to severe structural damage. This study investigates the mechanisms underlying the enhanced dynamic re... The afterburning of TNT and structural constraints in confined spaces significantly amplify the blast load,leading to severe structural damage. This study investigates the mechanisms underlying the enhanced dynamic response of reinforced concrete blast doors with four-sided restraints in confined space. Explosion tests with TNT charges ranging from 0.15 kg to 0.4 kg were conducted in a confined space,capturing overpressure loads and the dynamic response of the blast door. An internal explosion model incorporating the afterburning effect was developed using LS-DYNA software and validated against experimental data. The results reveal that the TNT afterburning effect amplifies both the initial peak overpressure and the quasi-static overpressure, resulting in increased deformation of the blast door.Within the 0.15-0.4 kg charge range, the initial overpressure peak and quasi-static overpressure increased by an average of 1.79 times and 2.21 times, respectively. Additionally, the afterburning effect enhanced the blast door's deflection by 177%. Compared to open-space scenarios, the cumulative deflection of the blast door due to repeated shock wave impacts is significantly greater in confined spaces. Furthermore, the quasi-static pressure arising from the structural constraints sustains the blast door's deflection at a high level. 展开更多
关键词 Internal explosion Afterburning effect Constraint effect Reinforced concrete blast door Dynamic response Enhancement effect
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Adsorption and visual detection of nitro explosives by pillar[n]arenes-based host–vip interactions 被引量:1
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作者 Xueru Zhao Aopu Wang +3 位作者 Shimin Wang Zhijie Song Li Ma Li Shao 《Chinese Chemical Letters》 2025年第4期211-215,共5页
Aromatic nitro compounds present substantial health and environmental concerns due to their toxic nature and potential explosive properties.Consequently,the development of host–vip molecular recognition systems for... Aromatic nitro compounds present substantial health and environmental concerns due to their toxic nature and potential explosive properties.Consequently,the development of host–vip molecular recognition systems for these compounds serves a dual-purpose:enabling the fabrication of high-performance sensors for detection and guiding the design of efficient adsorbents for environmental remediation.This study investigated the host–vip recognition behavior of perethylated pillar[n]arenes toward two aromatic nitro molecules,1-chloro-2,4-dinitrobenzene and picric acid.Various techniques including^(1)H NMR,2D NOESY NMR,and UV-vis spectroscopy were employed to explore the binding behavior between pillararenes and aromatic nitro vips in solution.Moreover,valuable single crystal structures were obtained to elucidate the distinct solid-state assembly behaviors of these vips with different pillararenes.The assembled solid-state supramolecular structures observed encompassed a 1:1 host–vip inclusion complex,an external binding complex,and an exo-wall tessellation complex.Furthermore,based on the findings from these systems,a pillararene-based test paper was developed for efficient picric acid detection,and the removal of picric acid from solution was also achieved using pillararenes powder.This research provides novel insights into the development of diverse host–vip systems toward hazardous compounds,offering potential applications in environmental protection and explosive detection domains. 展开更多
关键词 Pillar[n]arenes Host–vip interactions Aromatic nitro compounds Adsorptive separation Explosive detection
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Interfacial and Mechanical Properties of Cu/Al Composite Plates Manufactured by Rolling and Underwater Explosive Welding
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作者 Zhou Dapeng Liu Zhongshu +3 位作者 Huang Jiawen Chen Jinhua Chen Xiang Zhou Xiaohong 《稀有金属材料与工程》 北大核心 2025年第10期2461-2469,共9页
Cu/Al composite plates were fabricated using rolling and underwater explosive welding techniques,separately,to compare their interfacial microstructures and mechanical performance.Interface morphology,grain orientatio... Cu/Al composite plates were fabricated using rolling and underwater explosive welding techniques,separately,to compare their interfacial microstructures and mechanical performance.Interface morphology,grain orientation,grain boundary characteristics,and phase distribution were analyzed through optical microscope,scanning electron microscope,and electron backscattered diffractometer.Mechanical properties were assessed using tensile shear tests,90°bending tests,and hardness measurements.Vickers hardness and nanoindentation test results further provided information on the hardness distributions.Results indicate that the diffusion layer in rolled Cu/Al composites is relatively fragile,while that produced by underwater explosive welding features a diffusion layer of approximately 18μm in thickness,which is metallurgically bonded through atomic diffusion.The tensile shear strength of these composites ranges from 64.45 MPa to 70.84 MPa,and in the 90°three-point bending test,the underwater-explosive-welded samples exhibit superior flexural performance.This study elucidates the effects of different manufacturing methods on the interfacial properties and mechanical performance of Cu/Al composites,offering essential insights for the selection of manufacturing methods and applications. 展开更多
关键词 underwater explosive welding Cu/Al composites ROLLING EBSD NANOINDENTATION
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Numerical Simulation and Experiment of TA1/Q235 Composite Plate by Explosive Welding
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作者 Shi Changgen Jiang Jialin +2 位作者 Wang Haitao Luo Xuchuan Feng Ke 《稀有金属材料与工程》 北大核心 2025年第12期3032-3047,共16页
To further reduce the explosive thickness and to improve the bonding quality of titanium/steel composite plates,explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive(53#)un... To further reduce the explosive thickness and to improve the bonding quality of titanium/steel composite plates,explosive welding experiments of TA1/Q235 were conducted using a low detonation velocity explosive(53#)under the guidance of the explosive welding lower limit principle with the flyer plate thicknesses of 1,2,and 4 mm and gaps of 3,6,and 8 mm.The weldability window for titanium/steel explosive welding was calculated,and a quantitative relationship between dynamic and static process parameters was developed.Aβ-V_(p) high-speed inclined collision model was proposed,and two-dimensional numerical simulations for the explosive welding tests were performed using the smoothed particle hydrodynamics(SPH)algorithm,revealing the growth evolution mechanisms of the typical waveform morphology characteristics.Through microstructural characterization techniques,such as optical microscope,scanning electron microscope,energy dispersive spectrometer,and electron backscattered diffractometer,and mechanical property tests in terms of shear strength,bending performance,and impact toughness,the microstructure and mechanical properties of the interfaces of explosively welded TA1/Q235 composite plates were investigated.Results show that the quality of interface bonding is excellent,presenting typical waveform morphology with an average interface shear strength above 330 MPa and an average impact toughness exceeding 81 J.All samples can be bent to 180°without significant delamination or cracking defects. 展开更多
关键词 explosive welding weldability window SPH numerical simulation microstructure mechanical property
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Microstructure and Mechanical Properties of Explosively Welded Nickel/Steel Composite Plate Interface
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作者 Li Yan Wang Guicheng +3 位作者 Zhang Wenbin Yang Haijuan Li Jucai Liu Cuirong 《稀有金属材料与工程》 北大核心 2025年第8期1971-1979,共9页
High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscop... High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscope,scanning electron microscope,electron backscatter diffraction,and mechanical property testing,and the microstructural features and mechanical properties of the explosive welding interface were explored.The results show that along the direction of explosive welding,the pure nickel N6/steel 45#composite plate interface gradually evolves from a flat bond to a typical wavy bond.The grains at the crests and troughs exhibit high heterogeneity,and the closer to the interface,the finer the grains.Recrystallization and low-stress deformation bands are formed at the bonding interface.Nanoindentation tests reveal that plastic deformation occurs in the interfacial bonding zone,and the nanohardness values in the crest regions are higher than that in the trough regions.The tensile strength of the N6/45#interface is 599.8 MPa,with an average shear strength of 326.3 MPa.No separation phenomenon is observed between N6 and 45#after the bending test. 展开更多
关键词 explosive welding pure nickel N6/steel 45#composite plate MICROSTRUCTURE NANOINDENTATION
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Basic theory of dust explosion of energetic materials: A review
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作者 Mengli Yin Chunyan Wang +4 位作者 Haoyang Guo Yuhuai Shi Shengnan Shi Wenhui Wang Xiong Cao 《Defence Technology(防务技术)》 2025年第6期48-66,共19页
Due to the presence of nitro groups, the dust generated during the production and utilization of energetic materials may potentially lead to dust explosion even under low-oxygen or anaerobic conditions.Considering the... Due to the presence of nitro groups, the dust generated during the production and utilization of energetic materials may potentially lead to dust explosion even under low-oxygen or anaerobic conditions.Considering the high energy density of energetic materials, dust explosion can cause serious production safety accidents. Therefore, it is necessary to understand the dust explosion characteristics of energetic materials and the mechanism of dust explosion. According to the literature review, among various influencing factors, the physical and chemical properties of dust are the decisive factors affecting the explosion characteristics of dust. In addition to experimental studies, numerical simulation is another important tool. However, it is subjected to certain limitations. Moreover, it is essential but challenging to fully understand the underlying mechanism. In addition, given the safety hazards posed by dust explosion, explosion suppression has attracted extensive attention for research. Depending on the medium used, there are different forms of suppression, including powder explosion suppression, water spray explosion suppression, inert gas explosion suppression, porous material explosion suppression, and vacuum chamber explosion suppression. As for the selection of explosion suppression agent, consideration must be given to the characteristics of the material. Furthermore, the above research has laid a foundation for discussing the future progress in studying dust explosion of energetic materials, with nano dust and the constraints of existing technology as the focal point. 展开更多
关键词 Energetic dust explosion Influencing factors CFD simulation Explosion mechanism Explosion suppression Nano dust
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CO_(2)-H_(2)O co-electrolysis to CO/O_(2) for safe oxidative double carbonylation of ethylene/acetylene
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作者 Yanwei Cao Yunhao Qu +5 位作者 Bin Su Gongwei Wang Yang Huang Zhenmin Luo Lin Zhuang Lin He 《Chinese Journal of Catalysis》 2025年第7期202-210,共9页
Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that sy... Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that synergizes CO_(2)-H_(2)O co-electrolysis(producing CO/O_(2) feeds)with oxidative double carbonylation of ethylene/acetylene to synthesize CO_(2)-derived C_(4) diesters(dimethyl succinate,fumarate,and maleate).A group of versatile building blocks for manufacturing plasticizers,biodegradable polymers,and pharmaceutical intermediates.Remarkably,CO_(2) exhibits dual functionality:serving simultaneously as a CO/O_(2) source and an explosion suppressant during the oxidative carbonylation process.We systematically investigated the explosion-suppressing efficacy of CO_(2) in flammable gas mixtures(CO/O_(2),C_(2)H_(4)/CO/O_(2),and C_(2)H_(2)/CO/O_(2))across varying concentrations.Notably,the mixed gas stream from CO_(2)/H_(2)O co-electrolysis at an industrial-scale current densities of 400 mA/cm^(2),enabling direct utilization in oxidative double carbonylation reactions with exceptional compatibility and inherent safety.Extended applications were demonstrated through substrate scope expansion and gram-scale synthesis.This study establishes not only a safe protocol for oxidative carbonylation processes,but also opens an innovative pathway for sustainable CO_(2) valorization,including CO surrogate and explosion suppressant. 展开更多
关键词 Carbon dioxide ELECTROLYSIS Explosion suppressant Double Carbonylation Explosion limits ETHYLENE ACETYLENE
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Investigation on dynamic response of ship structure under multi-load combined action of underwater explosion considering cavitation effect
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作者 Yufan Chen Jian Qin +5 位作者 Zhichao Lai Xiangyao Meng Yanbo Wen Yipeng Jiang Zhenhuang Guan Ruiyuan Huang 《Acta Mechanica Sinica》 2025年第11期168-192,共25页
In this paper,the load characteristics of shock wave,bubble pulsating water jet and cavitation closure are studied by carrying out underwater explosion experiments and numerical simulation of fixed square plates with ... In this paper,the load characteristics of shock wave,bubble pulsating water jet and cavitation closure are studied by carrying out underwater explosion experiments and numerical simulation of fixed square plates with 2.5,5 and 10 g trinitrotoluene.The results show that under the combined action of multiple loads,the impulse of bubble pulsation and water jet load plays a leading role in the process of underwater explosion,and the impulse of cavitation closure load is greater than that of shock wave.The damage to the structure cannot be ignored,and the pressure time-history curve presents a“multi-peak”state,and it is pointed out that the water jet is a concentrated load.Then,the dynamic response of the full-scale model of the ship under the combined action of multiple loads is studied,and the dynamic response of the ship under different cabin water depths and different explosion distances is discussed.The results show that when the ship is empty,the damage degree of the ship is the most serious,and the influence of cavitation effect on the half cabin is weaker than that of the empty cabin,so the damage degree is the second,and the damage degree is the smallest when the cabin is full.When the distance parameter is less than 0.68,the shock wave and the after flow play a leading role in the dynamic response of the ship.When the distance parameter is between 0.68 and 1.38,the combined action of the bubble pulsating water jet and the cavitation closure multi-load causes the main damage to the ship.When the distance parameter is greater than 1.38,the bubble pulsation and the cavitation closure load play a leading role. 展开更多
关键词 Underwater explosion CAVITATION Multi-load Cabin water depth Explosion distance Full-size ship
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Electric explosion characteristics of multi-point series explosion foil initiator
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作者 Zheng Ning Lirong Bao +4 位作者 Ang Li Songmao Zhao Zeyu Cheng Peng Zhu Ruiqi Shen 《Defence Technology(防务技术)》 2025年第12期166-176,共11页
Investigating the characteristics of synchronous electrical explosions of multiple exploding foil initiators(EFI)in the same circuit,a four-point series-connected EFI circuit utilizing flexible flat cables was designe... Investigating the characteristics of synchronous electrical explosions of multiple exploding foil initiators(EFI)in the same circuit,a four-point series-connected EFI circuit utilizing flexible flat cables was designed to analyze the electrical explosion characteristics.Loop current and terminal voltages of each EFI were recorded to characterize the multi-point series-connected EFI explosion.The effects of voltage,capacitance,and loop length on the response time,energy deposition,and energy utilization efficiency of the multi-point series-connected EFI were explored.Based on the FIRESET model,a mathematical model for the multi-point series-connected EFI explosion was developed,and the influence of initial resistivity on the peak voltage during electrical explosion was quantitatively analyzed.Results indicate that the primary factor influencing the response time is the conduction performance of the switch,while the synchronization deviation is minimally affected by variations in voltage and capacitance.At an inter-electrode spacing of 50 mm,within the voltage range of 1,500–3,000 V and capacitance range of 0.22–1.5μF,the minimum and maximum synchronization deviations of the four-point EFI were 2 ns and 11 ns,respectively.As input energy increases,the deposited energy of the EFI rises,but the overall energy utilization efficiency decreases.The computational results of the proposed model align well with the experimental data.Furthermore,higher initial resistivity in the series-connected circuit corresponds to a higher peak voltage during electrical explosion.This work elucidates the characteristics of multi-point series-connected EFI explosions,offering valuable insights for the design of multi-point EFI circuits. 展开更多
关键词 Explosive foil initiator(EFI) Multipoint electric explosion Synchronism Series circuit Electric explosion curve
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2D Numerical Simulation of Blasting Crater and Breaking Fragmentations
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作者 Jingao Wu Yong Fan +1 位作者 Zhendong Leng Guangdong Yang 《Computer Modeling in Engineering & Sciences》 2025年第7期811-839,共29页
The formation process of blasting craters and blasting fragments is simulated using the continuumdiscontinuum element method(CDEM),providing a reference for blasting engineering design.The calculation model of the bla... The formation process of blasting craters and blasting fragments is simulated using the continuumdiscontinuum element method(CDEM),providing a reference for blasting engineering design.The calculation model of the blasting funnel is established,and the formation and fragmentation effect of the blasting crater under different explosive burial depths and different explosive package masses are numerically simulated.The propagation law of the explosion stress wave and the formation mechanism of the blasting crater are studied,and the relationship between the rock-crushing effect and blasting design parameters is quantitatively evaluated.Comparing the results of numerical simulation with the results of field tests and theoretical calculations indicated that the three are consistent,which proves the accuracy of numerical simulation.The results showed that the area of the blasting crater rises with the increase of explosive package mass and explosive burial depth.Taking the proportion of broken blocks with particle size ranging from 0.01 to 0.1 m as the research object,it can be found that the proportion of broken blocks with an explosive burial depth of 0.62 to 1.12 m is 0.45 to 0.18 times that with an explosive burial depth of 0.5 m.The proportion of broken blocks with an explosive radius of 4 to 12 cm is 1.14 to 3.29 times that with an explosive radius of 2 cm.The quantitative analysis of the blasting effect and blasting design parameters provides guidance for the design of blasting engineering. 展开更多
关键词 Blasting crater explosive burial depth explosive mass fragmentation gradation crater diameter CDEM
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