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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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An optimal design of the liquid-cooling plate channel in a power battery based on response surface methodology
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作者 Jinbo Zheng Jibin Jiang +2 位作者 Xiwei Yu Bingjun Yan Guofu Lian 《中国科学技术大学学报》 北大核心 2025年第2期52-65,51,I0002,共16页
The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the rel... The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters. 展开更多
关键词 response surface methodology power battery cooling channel optimal design
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2,3,5,4'-Tetrahydroxystilbene-2-O-β-glucoside Alleviates PCOS-like Characteristics by Upregulating The Expression of CYP19A1 in Granular Cells of Sinus Follicles to Inhibit Inflammatory Response
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作者 YAO Jian-Feng XU Bo +5 位作者 LIU Pin-Yue CHENG Di WEI Le PAN Xin-Yun MO Zhong-Cheng LI Ming 《生物化学与生物物理进展》 北大核心 2025年第3期735-750,共16页
Objective To investigate whether 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside(TSG)ameliorated polycystic ovary syndrome(PCOS)-like characteristics by inhibiting inflammation.Methods PCOS models were established ... Objective To investigate whether 2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside(TSG)ameliorated polycystic ovary syndrome(PCOS)-like characteristics by inhibiting inflammation.Methods PCOS models were established by injecting subcutaneously with dehydroepiandrosterone into female Sprague-Dawley rats,followed by receiving intraperitoneal injection of TSG.The granular cells(GCs)KGN were transfected with small interfering RNAs(si-NC and si-CYP19A1).The cells were preincubated with lipopolysaccharide(LPS)and then treated with or without TSG.The estrous cycle was monitored using vaginal exfoliated cells.The morphology of ovarian follicles was analyzed by H&E staining.ELISA was used to analyze estradiol(E2),testosterone(T),follicle stimulating hormone(FSH),luteinizing hormone(LH),IL-6,TNF-α,AGEs,CRP and Omentin-1 levels in serum.Immunohistochemistry was performed to analyze PCNA and CYP19A1 expressions in the GCs of ovaries.Tunel staining was executed to detect the apoptosis of GCs.Quantitative polymerase chain reaction(qPCR)and Western blot were implemented to measure the expression of CYP19A1 in the ovaries and transfected cells.qPCR was used to analyze the expression of IL-6 and TNF-αin the transfected cells treated with LPS and TSG.Results The estrous cycles were restored in TSG group.Compared with model group,the sinus follicles were reduced and corpus luteums were increased in TSG group.TSG group showed increased E2,and decreased T and LH,compared with model group.Pro-inflammatory factors(IL-6,TNF-α,CRP and AGEs)were decreased,and anti-inflammatory factor(Omentin-1)was increased in TSG group compared with those in model group.TSG could partially inhibit decrease of PNCA-positive GCs and increase of Tunel-positive GCs caused by PCOS.The CYP19A1 expression of GCs in TSG group was upregulated compared with model group.The expressions of IL-6 and TNFαin si-CYP19A1 cells were increased compared with si-NC cells.Compared with cells(si-NC and si-CYP19A1)treated without LPS,the expressions of IL-6 and TNF-αcells were increased,and the expression of CYP19A1 was downregulated in LPS-preincubated cells.Compared with cells treated with LPS,the expression of IL-6 and TNF-αwere decreased,and the expression of CYP19A1 was increased in cells treated with LPS and TSG.Compared with si-NC cells treated with LPS and TSG,the expressions of IL-6 and TNF-αcells were increased in the si-CYP19A1 cells treated with LPS and TSG.Conclusion TSG could alleviate PCOS-like characteristics by increasing the expression of CYP19A1 in GCs to inhibit inflammatory response. 展开更多
关键词 2 3 5 4'-tetrahydroxystilbene-2-O-β-glucoside granular cells CYP19A1 polycystic ovary syndrome inflammatory response
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Ballistic response mechanism and resistance-driven evaluation method of UHMWPE composite
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作者 Yemao He Johnny Qing Zhou +3 位作者 Yanan Jiao Hongshuai Lei Zeang Zhao Daining Fang 《Defence Technology(防务技术)》 2025年第2期1-16,共16页
The use of ultra-high molecular weight polyethylene(UHMWPE)composite in the design of lightweight protective equipment,has gained a lot of interest.However,there is an urgent need to understand the ballistic response ... The use of ultra-high molecular weight polyethylene(UHMWPE)composite in the design of lightweight protective equipment,has gained a lot of interest.However,there is an urgent need to understand the ballistic response mechanism and theoretical prediction model of performance.This paper explores the ballistic response mechanism of UHMWPE composite through experimental and simulation analyses.Then,a resistance-driven modeling method was proposed to establish a theoretical model for predicting the bulletproof performance.The ballistic response mechanism of UHMWPE composite encompassed three fundamental modes:local response,structural response,and coupled response.The occurrence ratio of these fundamental response modes during impact was dependent on the projectile velocity and laminate thickness.The bulletproof performance of laminate under different response modes was assessed based on the penetration depth of the projectile,the bulging height on the rear face of the laminate,the thickness of remaining sub-laminate,and residual velocity of the projectile.The absolute deviations of bulletproof performance indicator between theoretical value and experimental value were well within 11.13%,demonstrating that the established evaluation model possessed high degree of prediction accuracy. 展开更多
关键词 UHMWPE composite Ballistic response mechanism Theoretical model Performance evaluation
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Study of the explosion load characteristics and structural response law under a cabin water mist environment: Experimental tests and simulations
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作者 Xiaobin Li Ya Zhang +4 位作者 Yiheng Zhang Hai Huang Zhiping Wang Xingxing Wu Wei Chen 《Defence Technology(防务技术)》 2025年第7期387-404,共18页
To investigate the explosion load characteristics and structural response law in a water mist environment in a cabin,explosion experiments are carried out.The weakening rates of the initial peak overpressure,quasistat... To investigate the explosion load characteristics and structural response law in a water mist environment in a cabin,explosion experiments are carried out.The weakening rates of the initial peak overpressure,quasistatic pressure and structural residual deflection increase with increasing working pressure of the water mist nozzle.Specifically,the weakening rate of the initial peak overpressure ranges from 7.8%to 31.0%,the quasistatic pressure weakening rate ranges from 29.2%to 41.0%,and the weakening rate of the center of the plate residual deflection ranges from 10.8%to 34.4%under the various working pressures of the nozzles.To further explore the effect of water mist explosion suppression,a method for three-dimensional numerical simulations of water mist weakening the explosion shock wave is established to explore the explosion load characteristics of the compartment and the bulkhead response law.On the basis of the dimension analysis method,empirical formulas are derived to predict the residual deflection thickness in the center of the bulkheads.These findings provide the fundamental basis for the appli-cation of water mist in anti-explosive protection. 展开更多
关键词 Cabin explosion Blast response Fluidesolid coupling Load weakening Water mist suppression
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Optimization of Infrared-microwave Post-processing Process for 3D Printed Raspberry Preserves Based on AHP-CRITIC Hybrid Weighting Combined with Response Surface Method
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作者 Zheng Xianzhe Song Ruonan +2 位作者 Cong Hongyue Zhang Yuhan Xue Liangliang 《Journal of Northeast Agricultural University(English Edition)》 2025年第1期27-44,共18页
In order to improve the quality of 3D printed raspberry preserves after post-processing,microwave ovens combining infrared and microwave methods were utilized.The effects of infrared heating temperature,infrared heati... In order to improve the quality of 3D printed raspberry preserves after post-processing,microwave ovens combining infrared and microwave methods were utilized.The effects of infrared heating temperature,infrared heating time,microwave power,microwave heating time on the center temperature,moisture content,the chroma(C*),the total color difference(ΔE*),shape fidelity,hardness,and the total anthocyanin content of 3D printed raspberry preserves were analyzed by response surface method(RSM).The results showed that under combining with the two methods,infrared heating improved the fidelity and quality degradation of printed products,while microwave heating enhanced the efficiency of infrared heating.Infrared-microwave combination cooking could maintain relatively stable color appearance and shape of 3D printed raspberry preserves.The AHP–CRITIC hybrid weighting method combined with the response surface test to determine the comprehensive weights of the evaluation indicators optimized the process parameters,and the optimal process parameters were obtained:infrared heating temperature of 190℃,infrared heating time of 10 min and 30 s,microwave power of 300 W,and microwave heating time of 2 min and 6 s.The 3D printed raspberry cooking methods obtained under the optimal conditions seldom had color variation,porous structure,uniform texture,and high shape fidelity,which retained the characteristics of personalized manufacturing by 3D printing.This study could provide a reference for the postprocessing and quality control of 3D cooking methods. 展开更多
关键词 3D printing RASPBERRY MICROWAVE infrared heating hybrid weighting response surface method
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Investigation on dynamic response of liquid-filled cylindrical shellstructures under the action of combined blast and fragments loading
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作者 Zhujie Zhao Hailiang Hou +4 位作者 Dian Li Xiaowei Wu Yongqing Li Zhenghan Chen Linzhi Wu 《Defence Technology(防务技术)》 2025年第7期334-354,共21页
This study designs four types of liquid-filled cylindrical shell structures to investigate their protection characteristics against explosive shock waves and high-speed fragments.Bare charge and charge-driven prefabri... This study designs four types of liquid-filled cylindrical shell structures to investigate their protection characteristics against explosive shock waves and high-speed fragments.Bare charge and charge-driven prefabricated fragments are employed to examine the damage under blast shock waves and combined blast and fragments loading on various liquid-filled cylindrical shell structures.The test results are compared to numerical calculations and theoretical analysis for the structure's deformation,the liquid medium's movement,and the pressure waves'propagation characteristics under different liquid-filling methods.The results showed that the filling method influences the blast protection and the struc-ture's energy absorption performance.The external filling method reduces the structural deformation,and the internal filling method increases the damage effect.The gapped internal filling method improves the structure's energy absorption efficiency.The pressure wave loading on the liquid-filled cylindrical shell structure differs depending on filling methods.Explosive shock waves and high-speed fragments show a damage enhancement effect on the liquid-filled cylindrical shell structure,depending on the thickness of the internal liquid container layer.The specific impulse on the inner surface of the cylindrical shell positively correlates to the radial deformation of the cylindrical shell structure,and the external liquid layer limits the radial structural deformation. 展开更多
关键词 Blast wave Combined blast and fragments loading Filling method Liquid-filled structure Dynamic response
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Dynamic response of blast doors enhanced by enclosed-space TNT explosions: Experimental and numerical study
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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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Mechanical response and impact tendency index correction of gangue-coal combined structure
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作者 WEN Zhi-jie XU Chang-long +2 位作者 GONG Feng-qiang ZUO Yu-jun SONG Zhen-qi 《Journal of Central South University》 2025年第6期2288-2306,共19页
To investigate the mechanical response during failure and the impact tendency characteristics of gangue-coal combined structure,uniaxial compression tests were conducted on nine groups of combined structures,each with... To investigate the mechanical response during failure and the impact tendency characteristics of gangue-coal combined structure,uniaxial compression tests were conducted on nine groups of combined structures,each with varying gangue thicknesses and positions.The response patterns of compressive strength,elastic modulus,pre-peak accumulated energy,elastic energy index,and impact energy index were systematically analyzed.Furthermore,a new index for evaluating the impact tendency of gangue-containing coal was proposed,and its effectiveness was verified.The findings are as follows:(1)As the gangue thickness increases,both the compressive strength and the pre-peak energy of the combined structure decrease,whereas the elastic modulus increases accordingly.When the gangue is located in the lower middle position,the combined structure exhibits the lowest compressive strength and elastic modulus but the highest pre peak energy.(2)As the gangue shifts toward the middle position of the combined structure,the failure mode gradually transitions from comple te“crushing”failure to an incomplete“point-type”failure.As gangue thickness further increases,the failure region evolves from overall failure to localized failure,with the degree of failure shifting from complete to incomplete.The K_(crc)value corresponding to“crushing”complete failure is higher and has a stronger impact tendency compared to“point-type”incomplete failure.(3)The proposed comprehensive impact instability evaluation index K_(crc)for the gangue-coal combined structure has shown a significant positive correlation with compressive strength(R_(c))and impact energy index(K_(E)),further verifyi ng its rationality in comprehensively assessing the impact tendency of gangue-containing coal bodies.Applying this index to the evaluation of gangue-containing coal seams provides a more accurate reflection of their impact tendency compared with the residual energy index,which has a wide range of potential applications and practical significance. 展开更多
关键词 gangue-coal combined structure mechanical response peak elastic energy density difference impact tendency comprehensive impact instability index
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Environmental responsibility in sustainable business development
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作者 Mark W. Irwin 《化工新型材料》 CAS CSCD 北大核心 2010年第S1期12-12,共1页
China National Bluestar (Group) Co. , Ltd. is a Chinese-foreign joint venture enterprise jointly funded by China National Chemical Corporation (ChemChina) and The Blackstone Group. The business scope of Bluestar inclu... China National Bluestar (Group) Co. , Ltd. is a Chinese-foreign joint venture enterprise jointly funded by China National Chemical Corporation (ChemChina) and The Blackstone Group. The business scope of Bluestar includes research, develop-ment, manufacturing and marketing of chemical new materials, animal nutrient additives, water treatment technologies and fine chemicals, as well as the provision of a diverse range of technology and engineering services.The Company has experienced rapid development in size and internationalization in recent years and continues to invest in its business portfolio with significant emphasis on environmental responsibility as part of its commitment to Sustainable Development.Consistent with the view of the global chemical industry, as represented by the International Council of Chemical Associations (ICCA), Sustainable Development will only come about if three goals-economic, environmental and society-related-can be recon-ciled. The products and services offered by Bluestar ultimately touches many aspects of peoples lives on a daily basis ranging from basic needs such as food, clothing and housing to more discretionary areas such as consumer electronics and leisure activities. In ad-dition Bluestar interacts as a solution provider to other industries for cleaning, equipment and engineering services. Through priori-tizing environmental responsibility in all aspects of its technology and product development and implementing disciplined practices in operations, the Company is setting ambitious goals for improving its efficiency, reducing risks to health and the environment and making better products which, in turn, help individual and industry customers.Examples of ongoing investment in targeted portfolio expansion, a commitment to broad-based innovation and proactive efforts to reduce the environmental footprint of the business at all levels will be shown to demonstrate key measures for ensuring that the e-conomic, environmental and societal goals associated with Sustainable Development will be met. 展开更多
关键词 ENVIRONMENTAL responsibility SUSTAINABLE DEVELOPMENT CHEMICAL new materials
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On Lu Xun’s Responsibility Consciousness in Literary Translation
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作者 Gan Lu Luo Xianfeng 《学术界》 CSSCI 北大核心 2019年第7期208-213,共6页
In literary translation,Lu Xun shouldered the mission and responsibility to his motherland,the people,education,language,literature and art.In his opinion,foreign literature and culture would bring “fire and light” ... In literary translation,Lu Xun shouldered the mission and responsibility to his motherland,the people,education,language,literature and art.In his opinion,foreign literature and culture would bring “fire and light” to current society,provide Chinese children and youngsters with valuable readings and enhance the development of Chinese literature,language and characters.In his career of literary translation,Lu Xun fulfilled his long-cherished dream of being a “Spiritual Warrior” in China. 展开更多
关键词 Lu Xun LITERARY translation responsibility CONSCIOUSNESS value PURSUIT
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Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements 被引量:1
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作者 Yiming Zhang Ningfei Wang +3 位作者 Weihua Ma Ran Wang Long Bai Yi Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期473-484,共12页
In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measuremen... In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were performed.Two projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 g.The onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and analysed.Uniaxial compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching process.During the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant grain.The calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were observed.The dynamic mechanical response process of the dummy propellant grain was analysed in detail.The results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process. 展开更多
关键词 Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response
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Microscopic defects formation and dynamic mechanical response analysis of Q345 steel plate subjected to explosive load 被引量:1
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作者 Zhengqing Zhou Zechen Du +6 位作者 Yulong Zhang Guili Yang Ruixiang Wang Yuzhe Liu Peize Zhang Yaxin Zhang Xiao Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期430-442,共13页
As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate unde... As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate under the explosive load and its macroscopic dynamics simulation. Firstly, the defect characteristics of the steel plate were investigated by stereoscopic microscope(SM) and scanning electron microscope(SEM). At the macroscopic level, the defect was the formation of cave which was concentrated in the range of 0-3.0 cm from the explosion center, while at the microscopic level, the cavity and void formation were the typical damage characteristics. It also explains that the difference in defect morphology at different positions was the combining results of high temperature and high pressure. Secondly, the variation rules of mechanical properties of steel plate under explosive load were studied. The Arbitrary Lagrange-Euler(ALE) algorithm and multi-material fluid-structure coupling method were used to simulate the explosion process of steel plate. The accuracy of the method was verified by comparing the deformation of the simulation results with the experimental results, the pressure and stress at different positions on the surface of the steel plate were obtained. The simulation results indicated that the critical pressure causing the plate defects may be approximately 2.01 GPa. On this basis, it was found that the variation rules of surface pressure and microscopic defect area of the Q345 steel plate were strikingly similar, and the corresponding mathematical relationship between them was established. Compared with Monomolecular growth fitting models(MGFM) and Logistic fitting models(LFM), the relationship can be better expressed by cubic polynomial fitting model(CPFM). This paper illustrated that the explosive defect characteristics of metal plate at the microscopic level can be explored by analyzing its macroscopic dynamic mechanical response. 展开更多
关键词 Explosive load Q345 steel Micro defect Finite element simulation Dynamic response Data fitting
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Molecular Dynamics Simulation of Shock Response of CL-20 Co-crystals Containing Void Defects 被引量:1
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作者 Changlin Li Wei Yang +5 位作者 Qiang Gan Yajun Wang Lin Liang Wenbo Zhang Shuangfei Zhu Changgen Feng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期364-374,共11页
To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitro... To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitrobenzene(DNB),solvents ligands dimethyl carbonate(DMC) and gamma-butyrolactone(GBL)with void were simulated,using molecular dynamics method and reactive force field.It is found that the CL-20 co-crystals with void defects will form hot spots when impacted,significantly affecting the decomposition of molecules around the void.The degree of molecular fragmentation is relatively low under the reflection velocity of 2 km/s,and the main reactions are the formation of dimer and the shedding of nitro groups.The existence of voids reduces the safety of CL-20 co-crystals,which induced the sensitivity of energetic co-crystals CL-20/TNT and CL-20/DNB to increase more significantly.Detonation has occurred under the reflection velocity of 4 km/s,energetic co-crystals are easier to polymerize than solvent co-crystals,and are not obviously affected by voids.The results show that the energy of the wave decreases after sweeping over the void,which reduces the chemical reaction frequency downstream of the void and affects the detonation performance,especially the solvent co-crystals. 展开更多
关键词 CL-20 co-crystals Molecular dynamics simulation Reactive forcefield Impact response Hot spot Void defect
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Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof 被引量:1
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作者 ZHU Heng-zhong XU Lei WEN Zhi-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2488-2512,共25页
This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensi... This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensive field measurement program was conducted to determine entry deformation,roof fracture zone,and anchor bolt(cable)loading.The results indicate that GSERC deformation presents asymmetric characteristics.The maximum convergence near roof cutting side is 458 mm during the primary use process and 1120 mm during the secondary reuse process.The entry deformation is closely associated with the primary development stage,primary use stage,and secondary reuse stage.The key block movement of roof cutting structure,a complex stress environment,and a mismatch in the supporting design scheme are the failure mechanism of GSERC.A controlling ideology for mining states,including regional and stage divisions,was proposed.Both dynamic and permanent support schemes have been implemented in the field.Engineering practice results indicate that the new support scheme can efficiently ensure long-term entry safety and could be a reliable approach for other engineering practices. 展开更多
关键词 gob-side entry by roof cutting ground response failure mechanism following mining states control hard main roof
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Elastoplastic bridge deck response spectra of high-speed railway simply-supported girder bridge with CRTS Ⅱ track system 被引量:1
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作者 LIU Bo-lun HE Chang +2 位作者 LAI Zhi-peng JIANG Li-zhong LI Dong-ping 《Journal of Central South University》 CSCD 2024年第11期4174-4186,共13页
The seismic damage to ancillary facilities on high-speed railway(HSR)bridges can affect the normal movement of trains.To propose the bridge deck acceleration response spectra of the typical HSR simply-supported girder... The seismic damage to ancillary facilities on high-speed railway(HSR)bridges can affect the normal movement of trains.To propose the bridge deck acceleration response spectra of the typical HSR simply-supported girder bridge for simplifying the seismic responses analysis of the facilities on bridges,the finite element models of the HSR multi-span simply-supported girder bridges with CRTSII track were established,and the numerical model was validated by tests.Besides,the effects of the span number,peak ground acceleration(PGA),pier height on the seismic acceleration and response spectra of the bridge deck were investigated.Afterward,the bridge acceleration amplification factor curves and bridge deck response spectra with different PGAs and pier heights were obtained.The formula for bridge deck acceleration amplification factor,with a 95%guarantee rate,was fitted.Moreover,the finite element models of the overhead contact lines(OCL)mounted on rigid base and bridges were established to validate the fitted formula.The results indicated that the maximum seismic acceleration response is in the midspan of the beam.The proposed formula for the bridge deck acceleration response spectra can be used to analyze the earthquake response of the OCL and other ancillary facilities on HSR simply-supported girder bridges.The bridge deck acceleration response spectra are conservative in terms of structural safety and can significantly improving the analysis efficiency. 展开更多
关键词 high-speed railway CRT SⅡtrack-bridge system bridge deck acceleration response spectra overhead contact line seismic amplification effect
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Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA
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作者 Pham Binh Le Trung-Thanh Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期149-161,共13页
The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin lay... The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin layers(namely honeycomb-FGS shells)subjected to dynamic loading.Touratier's non-polynomial higher-order shear deformation theory(HSDT)is used due to its simplicity and performance.The governing equation is derived from Hamilton's principle.After verifying the present approach,the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail. 展开更多
关键词 IGA Elastic foundation Dynamic response FGM Auxetic honeycomb Shell
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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load
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作者 Zheng-qing Zhou Ze-chen Du +5 位作者 Xiao Wang Hui-ling Jiang Qiang Zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期580-593,共14页
As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive loads.In this paper,the evolution of microstructure and the mechanism of damage in the quasi-crackin... As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive loads.In this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were revealed.After the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro defects.In addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the plate.The stress parameters of the observation points were obtained through an effective numerical model.The mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro defects.The result shows that the generation and expansion of micro defects are related to the stress area(i.e.the upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile stress.Besides,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(i.e.the horizontal direction) were also studied.It was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decreased with the increase of the distance from the explosion center. 展开更多
关键词 Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation
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Theoretical and numerical research on the dynamic launch response of carbon fiber composite cartridges
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作者 Ruijie Zhang Hui Xu +2 位作者 Chenlei Huang Kun Liu Zhilin Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期426-436,共11页
Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of ... Understanding the dynamic response of composite material cartridges during the firing process is of great significance for improving their reliability and safety.A theoretical model describing the dynamic response of composite material cartridges is established based on the thick-walled cylinder theory and rate-dependent constitutive model of composite materials.The correctness of the theoretical model is validated through finite element simulations of cartridge deformation.The influence of chamber pressure and cartridge wall thickness on the cartridge's deformation process and stress distribution is analyzed.The results indicate that the primary deformation of composite material cartridges inside the chamber is elastic deformation.Compared to metal cartridges,composite material cartridges require higher pressure for touching-chamber and are more prone to developing gaps after unloading to ensure smooth extraction.During the deformation process,the touching-chamber behavior of the cartridge can improve the stress distribution.Under the same chamber pressure,the touching-chamber behavior can reduce the circumferential stress by approximately 30%.The inner wall surface of the cartridge is a critical area that requires attention.The touching-chamber behavior can be facilitated by appropriately reducing the cartridge wall thickness while ensuring overall strength.This study can provide guidance for the optimization design of composite material cartridges. 展开更多
关键词 Composite material cartridges Dynamic response Thick-walled cylinder theory Finite element simulation Toughing-chamber behavior
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Study on the Modern Value of Marxist Responsibility Ethics
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作者 Chen Fei Jiao Yuansheng 《学术界》 CSSCI 北大核心 2014年第4期249-254,共6页
The theory of Marxist responsibility ethics is based on the survival and development of human beings,having a strong humanistic color. Generally speaking,M arxist responsibility ethics includes the responsibility for ... The theory of Marxist responsibility ethics is based on the survival and development of human beings,having a strong humanistic color. Generally speaking,M arxist responsibility ethics includes the responsibility for human beings,the responsibility for nature and the responsibility for society. As far as the modern value function of M arxist responsibility is concerned,such a theory advocates respecting the natural environment,promoting the construction of ecological civilization,regulating the operation of the public power,strengthening the construction of responsible governments,promoting humanistic care,promoting the development of the principles of the political education in colleges and universities,advocating social responsibilities and encouraging enterprises to shoulder social responsibilities and so on. 展开更多
关键词 马克思主义 道德责任 现代价值 生态文明建设 社会责任 自然环境 人文色彩 价值功能
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