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变温条件下Energetic磁滞模型参数修正方法
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作者 陈彬 曾庆麟 +2 位作者 贾燕峰 黄力 唐波 《高电压技术》 EI CAS CSCD 北大核心 2024年第11期5174-5183,共10页
铁磁材料的磁滞特性存在温度依赖性,导致铁芯类设备的性能会受到温度的影响。但是现有的Energetic磁滞模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,首先研究了Energetic各个模型参数对磁滞回形状特征值的影响,分析了铁... 铁磁材料的磁滞特性存在温度依赖性,导致铁芯类设备的性能会受到温度的影响。但是现有的Energetic磁滞模型无法对温度进行有效表征,导致损耗计算结果误差较大。为此,首先研究了Energetic各个模型参数对磁滞回形状特征值的影响,分析了铁磁材料磁滞特性的温度依赖性。然后在采用公式法进行参数辨识的基础上,提取不同温度下磁滞回线的形状特征值,并引入居里温度和临界指数等系数,提出了各形状特征值关于温度的表达式。进一步将特征值表达式与各模型参数的辨识公式相结合,提出了考虑温度特性的模型参数辨识方法,建立了一种变温条件下的修正Energetic磁滞模型。最后,以纳米晶合金的极限磁滞回线测量结果为例,模拟该材料在各温度下的磁滞回线,并与多组测量值进行对比,验证了模型的准确性和可行性。 展开更多
关键词 energetic模型 温度特性 磁滞回线 参数辨识 铁磁材料 居里温度
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基于Energetic和改进Jiles-Atherton-Sablik模型的电工钢片动态磁致伸缩特性模拟 被引量:4
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作者 陈昊 李琳 王亚琦 《中国电机工程学报》 EI CSCD 北大核心 2024年第2期848-858,I0035,共12页
准确模拟电工钢片的动态磁致伸缩特性是电工装备铁心振动和噪声分析的关键步骤。该文提出一种基于Energetic磁滞模型和改进Jiles-Atherton-Sablik(J-A-S)模型的电工钢片动态磁致伸缩特性模拟方法。首先,基于静态Energetic磁滞模型和损... 准确模拟电工钢片的动态磁致伸缩特性是电工装备铁心振动和噪声分析的关键步骤。该文提出一种基于Energetic磁滞模型和改进Jiles-Atherton-Sablik(J-A-S)模型的电工钢片动态磁致伸缩特性模拟方法。首先,基于静态Energetic磁滞模型和损耗分离理论,考虑由励磁频率引起的动态损耗密度分量,并采用场分离技术建立动态Energetic磁滞模型。其次,将动态Energetic磁滞模型求解的动态磁场强度作为改进J-A-S模型的已知量,从而根据铁磁材料的非线性本构关系,建立以磁感应强度为输入量的动态磁致伸缩逆模型。在此基础上,设计电工钢片动态磁致伸缩曲线的模拟流程。最后,将所提方法的模拟结果与实测结果和现有方法模拟结果进行对比,可知所提方法的模拟结果与实测结果吻合更好,从而验证所提模拟方法的准确性。 展开更多
关键词 电工钢片 动态磁致伸缩特性 energetic磁滞模型 改进Jiles-Atherton-Sablik模型
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Progress on the application of graphene-based composites toward energetic materials:A review
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作者 Ting Zhang Xiaoming Gao +4 位作者 Jiachen Li Libai Xiao Hongxu Gao Fengqi Zhao Haixia Ma 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期95-116,共22页
Carbon material is an important additive in energetic materials.Graphene is a monolayer carbon material in which carbon atoms are arranged in two-dimensional honeycomb structure,who has special optical,electrical,and ... Carbon material is an important additive in energetic materials.Graphene is a monolayer carbon material in which carbon atoms are arranged in two-dimensional honeycomb structure,who has special optical,electrical,and mechanical properties.Recently,the application of graphene-based composites in energetic materials has received extensive attention.This review mainly summarizes the applications of graphene and graphene-based nanomaterials in energetic materials.The effects of these materials on the thermal stability,sensitivity,mechanical property,ignition and combustion of energetic materials were discussed.Furthermore,the progress of functionalized modification of graphene has been summarized,including covalent bonding modification and doping modification.These studies show that graphenebased materials exhibit excellent performances and might emerge as promising candidate for energetic materials. 展开更多
关键词 Graphene Desensitization Thermal decomposition Catalytic combustion energetic materials
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Loss of energetic particles due to feedback control of resistive wall mode in HL-3
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作者 Yifei ZHAO Yueqiang LIU +7 位作者 Guangzhou HAO Zhengxiong WANG Guanqi DONG Shuo WANG Chunyu LI Guanming YANG Yutian MIAO Yongqin WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第10期17-28,共12页
Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1(n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investig... Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1(n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investigated for the HL-3 tokamak.The MARS-F(Liu et al 2000 Phys.Plasmas 73681)code,facilitated by the test particle guiding center tracing module REORBIT,is utilized for the study.The RWM is found to generally produce no EP loss for cocurrent particles in HL-3.Assuming the same perturbation level at the sensor location for the close-loop system,feedback produces nearly the same loss of counter-current EPs compared to the open-loop case.Assuming however that the sensor signal is ten times smaller in the close-loop system than the open-loop counter part(reflecting the fact that the RWM is more stable with feedback),the counter-current EP loss is found significantly reduced in the former.Most of EP losses occur only for particles launched close to the plasma edge,while particles launched further away from the plasma boundary experience much less loss.The strike points of lost EPs on the HL-3 limiting surface become more scattered for particles launched closer to the plasma boundary.Taking into account the full gyro-orbit of particles while approaching the limiting surface,REORBIT finds slightly enhanced loss fraction. 展开更多
关键词 energetic particles resistive wall mode HL-3
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A review of ultra-high temperature heat-resistant energetic materials
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作者 Rongzheng Zhang Yuangang Xu +4 位作者 Feng Yang Pengcheng Wang Qiuhan Lin Hui Huang Ming Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期33-57,共25页
Heat-resistant energetic materials refer to a type of energetic materials that possess a high melting point,high stability and operational safety. By studying the structures of these energetic materials has showed tha... Heat-resistant energetic materials refer to a type of energetic materials that possess a high melting point,high stability and operational safety. By studying the structures of these energetic materials has showed that the thermal stability can be enhanced by introducing amino groups to form intra/inter-molecular hydrogen bonds, constructing conjugate systems and designing symmetrical structures. This article aims to review the physical and chemical properties of ultra-high temperature heat-resistant energetic compounds and provide valuable theoretical insights for the preparation of ultra-high temperature heatresistant energetic materials. We also analyze the selected 20 heat-resistant energetic materials with decomposition temperatures higher than 350℃, serving as templates for the synthesis of various highperformance heat-resistant energetic materials. 展开更多
关键词 Heat-resistant energetic materials Organic synthesis CONJUGATED Hydrogen bond Symmetrical structure STABILIZATION
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Alkylene-functionality in bridged and fused nitrogen-rich poly-cyclic energetic materials:Synthesis,structural diversity and energetic properties
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作者 Man Xu Nanxi Xiang +2 位作者 Ping Yin Qi Lai Siping Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期18-46,共29页
From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exh... From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark materials.The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich poly-heterocycles.Furthermore,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials.In this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials. 展开更多
关键词 energetic materials Alkyl bridge strategy Nitrogen-rich azoles Fused heterocycles AZOLES
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The Sigma-1 Receptor as a Pharmacologic Chaperone: Energetics
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作者 Robert B. Raffa Joseph V. Pergolizzi Jr. 《Journal of Biosciences and Medicines》 2024年第8期347-356,共10页
Initially thought to be an opioid receptor subtype, Sigma-1 receptors (S1R) are now known to be unique proteins that have chaperone-like properties. As such, they play critical roles in cellular signaling, homeostasis... Initially thought to be an opioid receptor subtype, Sigma-1 receptors (S1R) are now known to be unique proteins that have chaperone-like properties. As such, they play critical roles in cellular signaling, homeostasis, and cell survival. These roles offer significant insight for understanding homeostasis of normal physiologic processes, and the pathophysiologic consequences of disruption of normal function. Because of the broad nature of chaperone action, S1R agonists and antagonists represent potential drug discovery goals for the pharmacotherapeutic treatment of a variety of disorders that result from dysfunctional proteins. The present study summarizes the S1R as a pharmacologic chaperone crucial for protein folding and cellular homeostasis. Through literature review and thermodynamic analysis, it explores how S1R stabilizes target proteins, influencing neuroprotection and potential drug therapies. The binding of chaperones to target proteins is thermodynamically favorable, offering insights into treating diseases linked to protein misfolding. 展开更多
关键词 CHAPERONE Sigma-1 Receptor energeticS THERMODYNAMICS Isothermal Titration Microcalorimetry
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Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance
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作者 Binghui Duan Hongchang Mo +3 位作者 Bojun Tan Xianming Lu Bozhou Wang Ning Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期387-399,共13页
The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves... The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the problem.Two types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)layer.The morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was validated.The grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)binder.Due to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,respectively.Furthermore,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted polymers.These findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns. 展开更多
关键词 HMX crystals Polyalcohol bonding agent energetic polymer Core-shell structure Interfacial reinforcement
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Assessment of electrostatic discharge sensitivity of nitrogen-rich heterocyclic energetic compounds and their salts as high energy-density dangerous compounds:A study of structural variables
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作者 Mohammad Hossein Keshavarz Sedigheh Heydari Bani +1 位作者 Reza Bakhtiari Seyyed Hesamodin Hosseini 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期15-22,共8页
Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent years.The substantial energy-density content within these compounds can lead to potentially dangerous... Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent years.The substantial energy-density content within these compounds can lead to potentially dangerous explosive reactions when subjected to external stimuli such as electrical discharge.Therefore,developing a reliable model for predicting their electrostatic discharge sensitivity(ESD)becomes imperative.This study proposes a novel and straightforward model based on the presence of specific groups(-NH_(2) or-NH-,-N=N^(+)-O^(-)and-NNO_(2),-ONO_(2) or-NO_(2))under certain conditions to assess the ESD of NRHECs and their salts,employing interpretable structural parameters.Utilizing a comprehensive dataset comprising 54 ESD measurements of NRHECs and their salts,divided into 49/5 training/test sets,the model achieves promising results.The Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Maximum Error for the training set are reported as 0.16 J,0.12 J,and 0.5 J,respectively.Notably,the ratios RMSE(training)/RMSE(test),MAE(training)/MAE(test),and Max Error(training)/Max Error(test)are all greater than 1.0,indicating the robust predictive capabilities of the model.The presented model demonstrates its efficacy in providing a reliable assessment of ESD for the targeted NRHECs and their salts,without the need for intricate computer codes or expert involvement. 展开更多
关键词 Electrostatic discharge sensitivity Heterocyclic energetic compounds containing azole compound Interpretable structural parameter Safety
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Solar energetic particles intensity variations associated with a tilted-dipole 3D corotating interaction region
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作者 YuJi Zhu Fang Shen +2 位作者 Xi Luo Yang Wang BoFeng Tang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第5期797-810,共14页
The effect of a tilted-dipole three-dimensional corotating interaction region(CIR)on the transport and acceleration of solar energetic particles(SEPs)is studied.In this work,we discussed how the particle intensity lon... The effect of a tilted-dipole three-dimensional corotating interaction region(CIR)on the transport and acceleration of solar energetic particles(SEPs)is studied.In this work,we discussed how the particle intensity longitudinal and radial dependence might be influenced by the background structures.Moreover,we investigate how the spectral index distribution is modulated by the CIR structure We use the focused transport equation(FTE)to describe the propagation and acceleration of SEPs in a tilt-dipole 3D CIR,generated by the high-resolution 3D magnetohydrodynamic(MHD)model.The forward stochastic differential method is used to solve the FTE.The protons with theE~(-4.4)spectrum from 0.5 to 15 MeV are injected uniformly at the heliographic equator of 0.15 AU.Physical quantities are extracted along each interplanetary magnetic field(IMF)line to show the results.In the tilted-dipole CIR background,if injected from the solar equator at the inner boundary,particles in the slow flow are transported to higher latitudes due to the extension of the IMF lines to higher latitudes.The longitudinal patterns of the particles are dominated by the density of IMF lines.The focusing effect modulates the longitudinal variation of the particle intensity and gives rise to new longitudinal intensity peaks.The adiabatic effect largely increases the intensity fluctuation along the longitude.The structure of the solar wind can also lead to the difference of the indexαin the empirical functionI_(max)=kR~(-α),describing the radial variation of peak intensity according to our simulation.Under the influence of the CIR structure,the indexαvaries from 1.9 to 3.4 at 0.3-1.0 AU.The variation of the solar wind speed should be considered when estimating the radial dependence of the SEP peak intensity.The spectra indices rise near the CIR boundaries and drop near the stream interface(SI).The adiabatic effect makes the spatial variability of the spectral index larger.The spectral index could be similar at different radial distances in the CIR structure. 展开更多
关键词 solar energetic particle(SEP) corotating interaction regions(CIR) magnetohydrodynamic(MHD)
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Modification of a ReaxFF potential at short range for energetic materials
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作者 Weiyi Li Tao Wang +6 位作者 Wenhua Li Jintao Wang Wanxiao Guo Zexin Jiang Yilin Fang Xiyao Yun Ning Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第12期176-182,共7页
The ReaxFF can describe the properties of energetic materials(EMs)at equilibrium state,but does not work properly in simulating high-energy particle irradiation process because of its weak short-range interaction.In t... The ReaxFF can describe the properties of energetic materials(EMs)at equilibrium state,but does not work properly in simulating high-energy particle irradiation process because of its weak short-range interaction.In this paper,a modification was made for such a potential by connecting ZieglerBiersack-Littmark(ZBL)potential to ReaxFF-lg through comparing to Density Functional Theory(DFT)results to accurately describe short-range interactions.After modification,the newly fitted ReaxFF-lg/ZBL potential predicts better the equation of state for EMs In displacement cascade simulations,comparing to results from ab initio molecular dynamics(AIMD),ReaxFF-lg/ZBL presented the similar transferred energy from a primary knock-on atom to surrounding atoms,better than the original ReaxFF-lg potential.Further large-scale displacement cascade simulations indicated ReaxFF-lg/ZBL could be applied for cascade simulations with PKA energy from less than 1 keV to high energy(e.g.35 keV)cases,which is suitable for effectively simulating high-energy displacement cascades in EMs using molecular dynamics method. 展开更多
关键词 Molecular dynamics Potential modification energetic materials Displacement cascade Density functional theory Ab initio molecular dynamics
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Design,preparation,and characterization of a novel ZnO/CuO/Al energetic diode with dual functionality:Logic and destruction
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作者 Jialu Yang Jiaheng Hu +3 位作者 Yinghua Ye Jianbing Xu Yan Hu Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期57-68,共12页
Self-destructing chips have promising applications for securing data.This paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemi... Self-destructing chips have promising applications for securing data.This paper proposes a new concept of energetic diodes for the first time,which can be used for self-destructive chips.A simple two-step electrochemical deposition method is used to prepare ZnO/CuO/Al energetic diode,in which N-type ZnO and P-type CuO are constricted to a PN junction.This paper comprehensively discusses the material properties,morphology,semiconductor characteristics,and exploding performances of the energetic diode.Experimental results show that the energetic diode has typical rectification with a turn-on voltage of about 1.78 V and a reverse leakage current of about 3×10^(-4)A.When a constant voltage of 70 V loads to the energetic diode in the forward direction for about 0.14 s or 55 V loads in the reverse direction for about 0.17 s,the loaded power can excite the energetic diode exploding and the current rises to about100 A.Due to the unique performance of the energetic diode,it has a double function of rectification and explosion.The energetic diode can be used as a logic element in the normal chip to complete the regular operation,and it can release energy to destroy the chip accurately. 展开更多
关键词 energetic diode ZnO—CuO—Al thermite ZnO/CuO PN junction Electrical explosion performance Self-destructing chips
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Research Progress of Additive Manufacturing Technology in Energetic Material Field at Home and Abroad
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作者 Runpeng Jiang 《Journal of Materials Science and Chemical Engineering》 2024年第3期51-59,共9页
As a subversive manufacturing technology, additive manufacturing technology has many technical advantages such as high freedom of design and not limited by complex structure of parts. The application of additive manuf... As a subversive manufacturing technology, additive manufacturing technology has many technical advantages such as high freedom of design and not limited by complex structure of parts. The application of additive manufacturing technology to the charge molding of energetic materials will subvert the traditional manufacturing concept of energetic materials, realize the advanced charge design concept, shorten the research and development time of weapons and equipment, and improve the comprehensive performance of weapons and equipment, which is of great significance for the rapid development of high-tech weapons and equipment. This paper analyzes the research progress of additive manufacturing technology in the field of energetic materials at home and abroad and puts forward some suggestions for future research of this technology. . 展开更多
关键词 Additive Manufacturing Technology energetic Material Research Progress
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Synthesis and characterization of a 1,3-dibutylimidazolium azide([BBIm][N_(3)]) : A promising green energetic ionic liquid
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作者 Nawel Matmat Amir Abdelaziz +6 位作者 Djalal Trache Achour Sabrina Ahmed Fouzi Tarchoun Hani Boukeciat Sourbh Thakur Weiqiang Pang Thomas M.Klapotke 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期1-15,共15页
In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in thi... In the pursuit of advancing imidazolium-based energetic ionic liquids (EILs),the current study is devoted to the synthesis and characterization of 1,3-dibutyl-imidazolium azide ([BBIm][N_(3)]),as a novel member in this ionic liquids class.The chemical structure of this EIL was rigorously characterized and confirmed using FTIR spectroscopy,1D,and 2D-NMR analyses.The thermal behavior assessment was conducted through DSC and TGA experiments.DSC analysis revealed an endothermic glass transition at T_(g)=-61℃,followed by an exothermic degradation event at T_(onset)=311℃.Similarly,TGA thermograms exhibited a one-stage decomposition process resulting in 100% mass loss of the sample.Furthermore,the short-term thermal stability of the azide EIL was investigated by combining the non-isothermal TGA data with the TAS,it-KAS,and VYA/CE isoconversional kinetic approaches.Consequently,the Arrhenius parameters(E_(a)=154 kJ·mol^(-1),Log(A/s^(-1))=11.8) and the most probable reaction model g(a) were determined.The observed high decomposition temperatures and the significantly elevated activation energy affirm the enhanced thermal stability of the modified EIL.These findings revealed that[BBIm][N_(3)]EIL can be a promising candidate for advanced energetic material application. 展开更多
关键词 1 3-dibutyl-imidazolium azide[BBIm][N_(3)] energetic imidazolium-base ionic liquids 1D-/2D-NMR analyses Short-term thermal stability Isoconversional approaches
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谐波激励条件下铁心动态Energetic建模与验证 被引量:9
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作者 赵志刚 马习纹 +1 位作者 姬俊安 张鹏 《电工技术学报》 EI CSCD 北大核心 2020年第20期4241-4250,共10页
谐波激励条件下,表征铁心磁性能的磁滞回线发生明显畸变甚至出现局部回环,导致铁心损耗显著增加。为精确模拟和计算谐波激励条件下铁磁材料的磁滞特性和铁心损耗,该文在传统静态Energetic谐波磁滞模型的基础上,依据损耗分离理论,建立综... 谐波激励条件下,表征铁心磁性能的磁滞回线发生明显畸变甚至出现局部回环,导致铁心损耗显著增加。为精确模拟和计算谐波激励条件下铁磁材料的磁滞特性和铁心损耗,该文在传统静态Energetic谐波磁滞模型的基础上,依据损耗分离理论,建立综合考虑谐波特征的动态Energetic谐波磁滞模型。实现人工鱼群算法结合归一化处理技术对传统静态Energetic谐波磁滞模型参数的辨识,并提出一种可以有效考虑局部回环影响的动态损耗系数求解方法。搭建磁通密度波形可控的变压器铁心磁性能测试平台,对不同谐波阶次、谐波含量、谐波相位激励条件下的变压器铁心磁滞特性和损耗特性进行实验研究。通过模型仿真结果与实验数据的对比,验证了该文所建动态Energetic谐波磁滞模型的正确性和有效性。 展开更多
关键词 谐波激励 局部回环 动态energetic谐波磁滞模型 铁心损耗 磁滞特性
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基于Energetic模型的直流偏磁条件下电工钢片磁特性模拟及实验验证 被引量:15
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作者 赵志刚 马习纹 姬俊安 《中国电机工程学报》 EI CSCD 北大核心 2020年第14期4656-4665,共10页
直流偏磁条件下,变压器励磁电流畸变,损耗显著增加,导致变压器局部过热甚至绝缘老化。为研究直流偏磁对铁磁材料磁滞和损耗特性的影响,该文首先在静态Energetic磁滞模型的基础上,考虑涡流损耗和异常损耗对磁滞回线的影响,建立动态Energe... 直流偏磁条件下,变压器励磁电流畸变,损耗显著增加,导致变压器局部过热甚至绝缘老化。为研究直流偏磁对铁磁材料磁滞和损耗特性的影响,该文首先在静态Energetic磁滞模型的基础上,考虑涡流损耗和异常损耗对磁滞回线的影响,建立动态Energetic模型,并利用优化算法和损耗分离理论分别提取无偏磁条件的静态Energetic磁滞模型参数和动态损耗系数。通过对比磁滞回线仿真结果与实测数据,验证了所建模型的准确性;其次,搭建磁性能测试系统,实验获取了不同偏磁工况下电工钢片的磁滞特性和损耗特性数据,并分析直流偏磁量对磁滞损耗、动态损耗(涡流损耗与异常损耗之和)的影响规律;最后,基于上述分析结果,提出一种对不同偏磁条件下铁磁材料的磁滞回线及磁损耗进行预测的新方法。对比预测结果与实验结果,发现二者吻合较好,验证了该文方法的正确性。 展开更多
关键词 直流偏磁 动态energetic模型 爱泼斯坦方圈 磁损耗 磁滞回线
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Male Allocare in Rhinopithecus bieti at Xiaochangdu, Tibet: Is It Related to Energetic Stress? 被引量:2
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作者 向左甫 霍晟 肖文 《Zoological Research》 CAS CSCD 北大核心 2010年第2期189-197,共9页
Male allocare among nonhuman primates has frequently been investigated from the perspective of the caretaker. Here we examined whether male allocare relates to environmental factors or the females' energetic stress. ... Male allocare among nonhuman primates has frequently been investigated from the perspective of the caretaker. Here we examined whether male allocare relates to environmental factors or the females' energetic stress. We researched the possible differences of allocare between sexes in free-ranging black-and-white snub-nosed monkeys (Rhinopithecus bieti) in Tibet. A combination of stepwise least squares regression analysis was used to identify the influence of ecological factors (temperature, rainfall, etc.) and infant age that best account for seasonal variation of allocare. The results indicate, except for the functions of infant age, however, that male allocare is a negative function of temperature and female allocare is a positive function of temperature. Specifically, we tested the energetic stress hypothesis, which predicts that the energetic burden of females in a severe environment favour an increased rate of male allocare during the seasons of high energetic stress. We analyzed the allocare difference between high energetic stress season (Mar - Apr), when temperature was low, food availability was scarce, and infants were young, and low energetic stress season (Jun - Aug), based on data obtained during June 2003 - June 2004. Our results supported the energetic stress hypothesis because male allocare in high energetic stress season was higher than that of in low energetic stress season and female allocate was reverse. Therefore, we propose it is the energetic stress on female that make male allocare possible. Male take these interests for other aims and meet some functional hypothesis, which are addressed from the perspective of the male. 展开更多
关键词 Parental investment Intensive male infant caretaking energetic stress hypothesis COLOBINAE
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Adsorption/reaction energetics measured by microcalorimetry and correlated with reactivity on supported catalysts: A review 被引量:1
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作者 李林 林坚 +3 位作者 李筱玉 王爱琴 王晓东 张涛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2039-2052,共14页
The formations and transformations of the chemical bonds of reactants and intermediates on cata- lyst surfaces occur in conjunction with the evolution of heat during catalytic reactions. Measure- ment of this evolved ... The formations and transformations of the chemical bonds of reactants and intermediates on cata- lyst surfaces occur in conjunction with the evolution of heat during catalytic reactions. Measure- ment of this evolved heat is helpful in terms of understanding the nature of the interactions be- tween the catalyst and the adsorbed species, and provides insights into the reactivity of the catalyst. Although various techniques have previously been applied to assessments of evolved heat, direct measurements using a Tian-Calvet microcalorimeter are currently the most reliable method for this purpose. In this review, we summarize the relationship between the adsorption/reaction energetics determined by microcalorimetry and the reactivities of supported catalysts, and examine the im- portant role of microcalorimetry in understanding catalytic performance from the energetic point of view. 展开更多
关键词 Catalysis Microcalorimetry Reactivity energetics Binding strength Catalyst characterization
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基于模拟退火与Levenberg-Marquardt混合算法的Energetic磁滞模型参数提取 被引量:26
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作者 刘任 李琳 《中国电机工程学报》 EI CSCD 北大核心 2019年第3期875-884,966,共11页
利用Energetic磁滞模型进行磁滞特性模拟的首要任务在于模型参数的精确快速辨识。该文针对现有Energetic磁滞模型参数提取方法存在的收敛速度慢、求解精度低的问题,提出一种基于模拟退火(simulated annealing,SA)算法与Levenberg-Marqua... 利用Energetic磁滞模型进行磁滞特性模拟的首要任务在于模型参数的精确快速辨识。该文针对现有Energetic磁滞模型参数提取方法存在的收敛速度慢、求解精度低的问题,提出一种基于模拟退火(simulated annealing,SA)算法与Levenberg-Marquardt(L-M)混合算法的Energetic模型参数提取方法,其综合SA算法全局搜索能力强,以及L-M算法局部收敛速度快的优点。在混合算法迭代初期,采用SA算法快速锁定全局最优解所在区域;而后,根据引入的普适性混合算法切换过渡准则,将SA算法当前最优解赋予L-M算法;针对基于传统L-M算法提取Energetic模型参数出现的病态矩阵问题,该文将该模型参数的灵敏度函数矩阵进行归一化处理,从而推导出适用于Energetic模型参数快速提取的归一化L-M算法。归一化L-M算法在接收到SA算法提供的最优解后,将其作为初始值,快速收敛于全局最优解。仿真及实验结果表明,该文所提混合算法同时具有收敛速度快、提取精度高的优异性能,可实现Energetic模型参数的准确快速辨识。 展开更多
关键词 energetic磁滞模型 参数提取 模拟退火算法 LEVENBERG-MARQUARDT算法
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基于场分离技术与损耗统计理论的动态Energetic磁滞模型 被引量:20
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作者 刘任 李琳 《中国电机工程学报》 EI CSCD 北大核心 2019年第21期6412-6418,共7页
建立准确且高效的动态Energetic磁滞模型对磁性元器件的优化设计具有重要意义。然而,现有动态Energetic模型物理意义并不明确,且有效性尚未得到实验验证。针对原始静态Energetic模型仅包含磁滞损耗,而无法考虑磁性材料在交流激励下的动... 建立准确且高效的动态Energetic磁滞模型对磁性元器件的优化设计具有重要意义。然而,现有动态Energetic模型物理意义并不明确,且有效性尚未得到实验验证。针对原始静态Energetic模型仅包含磁滞损耗,而无法考虑磁性材料在交流激励下的动态涡流及剩余损耗的问题,首先从能量平衡的角度出发,基于场分离技术与损耗分离的思想,推导了各损耗分量与其对应的磁场强度分量之间的等效关系;其次,利用损耗统计理论推导涡流与剩余损耗相应磁场强度分量的解析表达式,从而在此基础上运用场量叠加的方式,建立一种基于场分离技术与损耗统计理论的新型解析动态Energetic模型。仿真及实验结果表明,所提动态Energetic模型不仅物理意义清晰明确,同时具有较高的准确性与实用性。 展开更多
关键词 动态energetic磁滞模型 能量平衡 场分离技术 损耗统计理论
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