期刊文献+
共找到85,508篇文章
< 1 2 250 >
每页显示 20 50 100
Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner 被引量:2
1
作者 Bihui Hong Wenbin Li +2 位作者 Yiming Li Zhiwei Guo Binyou Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期374-385,共12页
This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double... This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner. 展开更多
关键词 Shaped charge Chemical vapor deposition TUNGSTEN double-layer charge liner X-ray PENETRATION
下载PDF
Discovery and Significance of the Triassic–Late Paleozoic Double-layered Basement in the Songliao Basin:Based on the Complete Coring Data from ICDP Borehole SK2
2
作者 YANG Zhuolong WANG Pujun +2 位作者 GAO Youfeng GAO Chuancheng TANG Xin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期75-76,共2页
The Songliao Basin(SLB)covers an area of approximately 260,000 km2in northeastern Asia and preserves a continuous and complete Cretaceous terrestrial record(Wang et al.,2021).The region is the most important petrolife... The Songliao Basin(SLB)covers an area of approximately 260,000 km2in northeastern Asia and preserves a continuous and complete Cretaceous terrestrial record(Wang et al.,2021).The region is the most important petroliferous sedimentary basin in China because of its continual annual oil and gas equivalent production of tens of millions of tons(ca.220–440 million barrels per year)since 1959.The SLB was previously thought to have developed on Hercynian basement and accumulated continuous sedimentary deposits during the Late Jurassic and Cretaceous(Wan et al.,2013;Wang et al.,2016). 展开更多
关键词 double-layered basement ICDP Triassic and Paleozoic Songliao Basin
下载PDF
Performance and Application of Double-layered Microcapsule Corrosion Inhibitors
3
作者 余海燕 WANG Yingxiang +2 位作者 WANG Ruizhi HU Lintong WANG Tianlei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期845-853,共9页
Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material co... Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material combining the solvent evaporation method and spray drying method.The protection by the outer capsule wall was used to prolong the service life of the corrosion inhibitor.The dispersion,encapsulation,thermal stability of microcapsules,and the degradation rate of capsule wall in concrete pore solution were analyzed by ultra-deep field microscopy,scanning electron microscopy,thermal analyzer,and sodium ion release rate analysis.The microcapsules were incorporated into mortar samples containing steel reinforcement,and the effects of double-layered microcapsule corrosion inhibitors on the performance of the cement matrix and the actual corrosion-inhibiting effect were analyzed.The experimental results show that the double-layered microcapsules have a moderate particle size and uniform distribution,and the capsules were completely wrapped.The microcapsules as a whole have good thermal stability below 230 ℃.The monolayer membrane structure microcapsules completely broke within 1 day in the simulated concrete pore solution,and the double-layer membrane structure prolonged the service life of the microcapsules to 80 days in the simulated concrete pore solution before the core material was completely released.The mortar samples containing steel reinforcement incorporated with the double-layered microcapsule corrosion inhibitors still maintained a higher corrosion potential than the monolayer microcapsule corrosion inhibitors control group at 60 days.The incorporation of double-layered microcapsules into the cement matrix has no significant adverse effect on the setting time and early strength. 展开更多
关键词 corrosion inhibitors MICROCAPSULE double-layer structure potentiodynamic polarization curve
原文传递
基于DWC PCIE Core的数据传输系统设计 被引量:3
4
作者 刘肖婷 《铁路通信信号工程技术》 2024年第1期26-29,46,共5页
在铁路信号系统中,为有效减少铁路信号系统设备CPU资源占用率,设计一种基于DWC PCIE Core的数据发送与接收系统。该系统采用内嵌ARM Cortex-A9双核的FPGA开发板套件,利用FPGA的灵活性和可扩展性,采用可配置的PCIE硬核IP模块以及以太网硬... 在铁路信号系统中,为有效减少铁路信号系统设备CPU资源占用率,设计一种基于DWC PCIE Core的数据发送与接收系统。该系统采用内嵌ARM Cortex-A9双核的FPGA开发板套件,利用FPGA的灵活性和可扩展性,采用可配置的PCIE硬核IP模块以及以太网硬核IP模块。该系统主要介绍Host PC与FPGA之间基于PCIE 2.0的DMA数据传输以及FPGA之间基于GMAC的以太网数据传输,通过PCIe总线、以太网基于DMA模块实现数据高速可靠传输。 展开更多
关键词 DWC PCIE core FPGA 数据传输 DMA
下载PDF
Time-sequenced damage behavior of reactive projectile impacting double-layer plates
5
作者 Ying Yuan Yi-qiang Cai +3 位作者 Huan-guo Guo Peng-wan Chen Rui Liu Hai-fu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期263-272,共10页
The time-sequenced damage behavior of the reactive projectile impacting double-layer plates is discussed.The analytical model considering the combined effect of kinetic and chemical energy is developed to reveal the d... The time-sequenced damage behavior of the reactive projectile impacting double-layer plates is discussed.The analytical model considering the combined effect of kinetic and chemical energy is developed to reveal the damage mechanism.The influences of impact velocity and reactive projectile chemical characteristics on the damage effect are decoupled analyzed based on this model.These analyses indicate that the high energy releasing efficiency and fast reaction propagation velocity of the reactive projectile are conducive to enhancing the damage effect.The experiments with various reactive projectiles impact velocity increasing from 702 to 1385 m/s were conducted to verify this model.The experimental results presented that,the damage hole radius of the rear-plate increases with the increase of impact velocity.At the impact velocity of 1350 m/s,the radius of damage hole formed by PTFE/Al/Bi_(2)O_(3),PTFE/Al/MoO_(3),PTFE/Al/Fe_(2)O_(3)projectile on the rear-plate become smaller in sequence.These results are consistent with the analytical model prediction,demonstrating that this model can predict the damage effect quantitatively.This work is of constructive significance to the application of reactive projectiles. 展开更多
关键词 Reactive projectile Damage behaviors Impact double-layer plates
下载PDF
Gas-and plasma-driven hydrogen permeation behavior of stagnant eutectic-solid GaInSn/Fe double-layer structure
6
作者 荆文娜 刘建星 +8 位作者 郭恒鑫 王思蜀 毕海林 陈波 陈建军 王宏彬 韦建军 叶宗标 芶富均 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期482-492,共11页
Gas-driven permeation(GDP)and plasma-driven permeation(PDP)of hydrogen gas through Ga In Sn/Fe are systematically investigated in this work.The permeation parameters of hydrogen through Ga In Sn/Fe,including diffusivi... Gas-driven permeation(GDP)and plasma-driven permeation(PDP)of hydrogen gas through Ga In Sn/Fe are systematically investigated in this work.The permeation parameters of hydrogen through Ga In Sn/Fe,including diffusivity,Sieverts'constant,permeability,and surface recombination coefficient are obtained.The permeation flux of hydrogen through Ga In Sn/Fe shows great dependence on external conditions such as temperature,hydrogen pressure,and thickness of liquid Ga In Sn.Furthermore,the hydrogen permeation behavior through Ga In Sn/Fe is well consistent with the multilayer permeation theory.In PDP and GDP experiments,hydrogen through Ga In Sn/Fe satisfies the diffusion-limited regime.In addition,the permeation flux of PDP is greater than that of GDP.The increase of hydrogen plasma density hardly causes the hydrogen PDP flux to change within the test scope of this work,which is due to the dissolution saturation.These findings provide guidance for a comprehensive and systematic understanding of hydrogen isotope recycling,permeation,and retention in plasma-facing components under actual conditions. 展开更多
关键词 liquid metals double-layer gas-driven permeation plasma-driven permeation
原文传递
Preparation and Microwave Absorbing Properties of Double-layer Fine Iron Tailings Cementitious Materials
7
作者 LI Huawei WANG Rong +3 位作者 WANG Yulin LIU Feiyu WANG Qian WEI Muwang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1126-1135,共10页
To develop the microwave absorbing(MA)properties of cementitious material mixed with mine solid waste,the iron tailings cementitious microwave absorbing materials were prepared.The iron tailings was treated into diffe... To develop the microwave absorbing(MA)properties of cementitious material mixed with mine solid waste,the iron tailings cementitious microwave absorbing materials were prepared.The iron tailings was treated into different particle sizes by planetary ball mill,and the physicochemical properties of iron tailings were tested by laser particle size analyzer and scanning electron microscope(SEM).The electromagnetic parameters of iron tailings cementitious materials were characterized by a vector network analyzer and simulated MA properties,and the MA properties of iron tailings-cement composite system with steel fiber as absorber was studied.Based on the design of the single-layer structure,optimum mix ratio and thickness configuration method of double-layer structure were further studied,meanwhile,the mechanical properties and engineering application were analyzed and discussed.The results show that the particle size of iron tailings can afiect its electromagnetic behavior in cementitious materials,and the smaller particles lead the increase of demagnetisation efiect induced by domain wall motion and achieve better microwave absorbing properties in cementitious materials.When the thickness of matching layer and absorbing layer is 5 mm,the optimized microwave absorbing properties of C1/C3 double-layer cementitious material can obtain optimal RL value of-27.61 dB and efiective absorbing bandwidth of 0.97 GHz,which attributes to the synergistic efiect of impedance matching and attenuation characteristics.The double-layer microwave absorbing materials obtain excellent absorbing properties and show great design flexibility and diversity,which can be used as a suitable candidate for the preparation of favorable microwave absorbing cementitious materials. 展开更多
关键词 microwave absorbing properties iron tailings electromagnetic parameters single-layer structure double-layer structure impedance matching
原文传递
Double-Layer-Optimizing Method of Hybrid Energy Storage Microgrid Based on Improved Grey Wolf Optimization
8
作者 Xianjing Zhong Xianbo Sun Yuhan Wu 《Computers, Materials & Continua》 SCIE EI 2023年第8期1599-1619,共21页
To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing confi... To reduce the comprehensive costs of the construction and operation of microgrids and to minimize the power fluctuations caused by randomness and intermittency in distributed generation,a double-layer optimizing configuration method of hybrid energy storage microgrid based on improved grey wolf optimization(IGWO)is proposed.Firstly,building a microgrid system containing a wind-solar power station and electric-hydrogen coupling hybrid energy storage system.Secondly,the minimum comprehensive cost of the construction and operation of the microgrid is taken as the outer objective function,and the minimum peak-to-valley of the microgrid’s daily output is taken as the inner objective function.By iterating through the outer and inner layers,the system improves operational stability while achieving economic configuration.Then,using the energy-self-smoothness of the microgrid as the evaluation index,a double-layer optimizing configuration method of the microgrid is constructed.Finally,to improve the disadvantages of grey wolf optimization(GWO),such as slow convergence in the later period and easy falling into local optima,by introducing the convergence factor nonlinear adjustment strategy and Cauchy mutation operator,an IGWO with excellent global performance is proposed.After testing with the typical test functions,the superiority of IGWO is verified.Next,using IGWO to solve the double-layer model.The case analysis shows that compared to GWO and particle swarm optimization(PSO),the IGWO reduced the comprehensive cost by 15.6%and 18.8%,respectively.Therefore,the proposed double-layer optimizationmethod of capacity configuration ofmicrogrid with wind-solar-hybrid energy storage based on IGWO could effectively improve the independence and stability of the microgrid and significantly reduce the comprehensive cost. 展开更多
关键词 Wind-solar microgrid hybrid energy storage optimization configuration double-layer optimization model IGWO
下载PDF
Enhancing electromagnetic wave absorption with core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres 被引量:1
9
作者 Xuewen Jiang Qian Wang +7 位作者 Limeng Song Hongxia Lu Hongliang Xu Gang Shao Hailong Wang Rui Zhang Changan Wang Bingbing Fan 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期90-104,共15页
Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric const... Material composition and structural design are important factors influencing the electromagnetic wave(EMW)absorption performance of materials.To alleviate the impedance mismatch attributed to the high dielectric constant of Ti_(3)C_(2)T_(x)MXene,we have successfully synthesized core‐shell structured SiO_(2)@MXene@MoS_(2)nanospheres.This architecture,comprising SiO_(2) as the core,MXene as the intermediate layer,and MoS_(2) as the outer shell,is achieved through an electrostatic self‐assembly method combined with a hydrothermal process.This complex core‐shell structure not only provides a variety of loss mechanisms that effectively dissipate electromagnetic energy but also prevents self‐aggregation of MXene and MoS_(2) nanosheets.Notably,the synergistic combination of SiO_(2) and MoS_(2) with highly conductive MXene enables the suitable dielectric constant of the composites,ensuring optimal impedance matching.Therefore,the core‐shell structured SiO_(2)@MXene@MoS_(2) nanospheres exhibit excellent EMW absorption performance,featuring a remarkable minimum reflection loss(RL_(min))of−52.11 dB(2.4 mm).It is noteworthy that these nanospheres achieve an ultra‐wide effective absorption bandwidth(EAB)of 6.72 GHz.This work provides a novel approach for designing and synthesizing high‐performance EMW absorbers characterized by“wide bandwidth and strong reflection loss.” 展开更多
关键词 core‐shell structure electromagnetic wave absorption multiloss mechanism SiO_(2)@MXene@MoS_(2)
下载PDF
基于C#.NET Core技术与三菱PLC的通信方式研究
10
作者 高宝东 《黑龙江科学》 2024年第8期95-97,101,共4页
为了实现智能制造产业中的实时监控、数据共享及各设备间的协同工作,在.NET Core 7.0环境下研究三菱小型PLC与计算机之间的串口通信和MC协议通信方式,开发了三菱PLC通信管理系统,成功实现了上位机对现场PLC的数据采集和远程操作,使用云... 为了实现智能制造产业中的实时监控、数据共享及各设备间的协同工作,在.NET Core 7.0环境下研究三菱小型PLC与计算机之间的串口通信和MC协议通信方式,开发了三菱PLC通信管理系统,成功实现了上位机对现场PLC的数据采集和远程操作,使用云端数据库技术和数据库管理工具对数据进行分析处理,从而实现对设备工作状态的实时监控及故障分析。 展开更多
关键词 .NET core PLC 通信 串口 MC协议
下载PDF
Structure–performance relationship of Au nanoclusters in electrocatalysis:Metal core and ligand structure
11
作者 Bowen Li Lianmei Kang +3 位作者 Yongfeng Lun Jinli Yu Shuqin Song Yi Wang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期63-89,共27页
Remarkable progress has characterized the field of electrocatalysis in recent decades,driven in part by an enhanced comprehension of catalyst structures and mechanisms at the nanoscale.Atomically precise metal nanoclu... Remarkable progress has characterized the field of electrocatalysis in recent decades,driven in part by an enhanced comprehension of catalyst structures and mechanisms at the nanoscale.Atomically precise metal nanoclusters,serving as exemplary models,significantly expand the range of accessible structures through diverse cores and ligands,creating an exceptional platform for the investigation of catalytic reactions.Notably,ligand‐protected Au nanoclusters(NCs)with precisely defined core numbers offer a distinct advantage in elucidating the correlation between their specific structures and the reaction mechanisms in electrocatalysis.The strategic modulation of the fine microstructures of Au NCs presents crucial opportunities for tailoring their electrocatalytic performance across various reactions.This review delves into the profound structural effects of Au NC cores and ligands in electrocatalysis,elucidating their underlying mechanisms.A detailed exploration of the fundamentals of Au NCs,considering core and ligand structures,follows.Subsequently,the interaction between the core and ligand structures of Au NCs and their impact on electrocatalytic performance in diverse reactions are examined.Concluding the discourse,challenges and personal prospects are presented to guide the rational design of efficient electrocatalysts and advance electrocatalytic reactions. 展开更多
关键词 Au nanoclusters core electrocatalytic performance LIGAND STRUCTURES
下载PDF
SIHC:一种高效的时态图上k-core查询算法
12
作者 周军锋 王春花 +1 位作者 杜明 陈子阳 《计算机学报》 EI CAS CSCD 北大核心 2024年第5期1045-1064,共20页
许多实体之间的关系可以建模为时态图,其中每条边都与表示其发生的时间相关联,k-core是捕获密集子图的基本模型,在近些年得到了广泛研究.给定时间区间I=[s,e]和k值,时态图G上的k-core子图查询从区间I对应的快照图GI中返回相应的k-core子... 许多实体之间的关系可以建模为时态图,其中每条边都与表示其发生的时间相关联,k-core是捕获密集子图的基本模型,在近些年得到了广泛研究.给定时间区间I=[s,e]和k值,时态图G上的k-core子图查询从区间I对应的快照图GI中返回相应的k-core子图.针对时态图中的k-core子图查询问题,现有方法是基于PHC索引(Pruned Historical Core-Index)的算法.对任意可能的k值,PHC索引维护了所有可能出现在某个时间区间的k-core子图中的顶点集Sk,且为集合中每个顶点存储了一组时间区间,用于判定该点是否属于给定时间区间的k-core子图.基于PHC索引查询k-core子图时,需要访问Sk集合中的所有顶点,并判断每个顶点的可满足性.由于Sk集合对应于最大区间快照图的k-core子图里的所有顶点,且实际中用户查询区间对应的快照图往往比最大区间快照图小得多,基于PHC索引的查询算法存在许多无效判断,需要对大量不在结果集中的顶点进行检测,且无效检测次数随着查询区间的缩短而增多,从而导致算法效率较低.针对该问题,本文提出一种新的索引,即最短区间历史核索引SIHC(Shortest Interval Historical Core Index).SIHC索引的基本思想是通过维护最短k核区间到顶点的倒排表,查询处理时,可基于用户给定的时间区间定位到SIHC索引中满足条件的区间,进而直接得到满足条件的k-core子图中的顶点,从而避免了基于PHC索引进行查询时所需的大量无效判断.我们从理论上证明了基于SIHC索引处理时态图上k-core子图查询的正确性,并设计了高效的索引构建算法.最后,基于真实世界的时态图进行了实验,实验结果表明本文提出的算法比现有算法快1~2个数量级. 展开更多
关键词 图数据管理 时态图 密集子图 k-core 最短k核区间
下载PDF
Optimization for sound insulation of a sandwich plate with a corrugation and auxetic honeycomb hybrid core
13
作者 Fenglian LI Yiping WANG Yuxing ZOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1595-1612,共18页
A sandwich plate with a corrugation and auxetic honeycomb hybrid core is constructed,and its sound insulation and optimization are investigated.First,the motion governing equation of the sandwich plate is established ... A sandwich plate with a corrugation and auxetic honeycomb hybrid core is constructed,and its sound insulation and optimization are investigated.First,the motion governing equation of the sandwich plate is established by the third-order shear deformation theory(TSDT),and then combined with the fluid-structure coupling conditions,and the sound insulation is solved.The theoretical results are validated by COMSOL simulation results,and the effects of the structural parameter on the sound insulation are analyzed.Finally,the standard genetic algorithm is adopted to optimize the sound insulation of the sandwich plate. 展开更多
关键词 OPTIMIZATION sound insulation hybrid core layer genetic algorithm
下载PDF
Structural Analysis for Qazzaz Metamorphic Core Complex,Northwestern Arabian Shield,Saudi Arabia
14
作者 Mansour H.AL-HASHIM Osama M.K.KASSEM 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1187-1201,共15页
Identifying deformational mechanisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic development.Thirty-three samples ... Identifying deformational mechanisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic development.Thirty-three samples were taken from the Qazzaz metamorphic core complex to estimate the finite strain for felsic and mafic minerals.These samples included gneisses rocks,monzogranite,and metavolcano-sedimentary rocks for both the Thalbah and Bayda groups.Using the Rf/j and Fry methods,the axial ratios(XZ)range about 2.20 to 7.10 and 1.90 to 9.10,respectively.For various rock units,the strain measurements show moderate to highly deformation.Most of the observed samples show shallow WNW dipping along a N to WNW trend of finite strain(X).The short axes(Z)based to be subvertical foliation related with a subhorizontal foliation.The results demonstrate that contacts generated at semi-brittle to ductile deformation and that the strain of magnitude has the same value for different lithologic units.It concluded that nappe generation in orogens results from pure shear deformation. 展开更多
关键词 Finite strain metamorphic core complex Qazzaz area Saudi Arabia
下载PDF
A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
15
作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
下载PDF
Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory
16
作者 F.SHIRDELAN M.MOHAMMADIMEHR F.BARGOZINI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1773-1790,共18页
Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive appearance.However,the inability of controlling and regulati... Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive appearance.However,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to scientists.In this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation theory.The core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear forces.The results show that the honeycomb core has a greater effect on the vibrations.When the parameters related to the core and the weight percentage of graphene increase,the frequency increases.The uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency increases.Furthermore,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(FOSDT)align closely.However,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the FOSDT being lower than those in the TSDT. 展开更多
关键词 vibration and control doubly curved shell micro-composite HONEYCOMB TRUSS corrugate core
下载PDF
Detecting the core of a network by the centralities of the nodes
17
作者 马佩杰 任学藻 +1 位作者 朱军芳 蒋艳群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期615-621,共7页
Many networks exhibit the core/periphery structure.Core/periphery structure is a type of meso-scale structure that consists of densely connected core nodes and sparsely connected peripheral nodes.Core nodes tend to be... Many networks exhibit the core/periphery structure.Core/periphery structure is a type of meso-scale structure that consists of densely connected core nodes and sparsely connected peripheral nodes.Core nodes tend to be well-connected,both among themselves and to peripheral nodes,which tend not to be well-connected to other nodes.In this brief report,we propose a new method to detect the core of a network by the centrality of each node.It is discovered that such nodes with non-negative centralities often consist in the core of the networks.The simulation is carried out on different real networks.The results are checked by the objective function.The checked results may show the effectiveness of the simulation results by the centralities of the nodes on the real networks.Furthermore,we discuss the characters of networks with the single core/periphery structure and point out the scope of the application of our method at the end of this paper. 展开更多
关键词 complex network core/periphery structure the objective function
原文传递
Core level excitation spectra of La and Mn ions in LaMnO3
18
作者 李福建 程新路 张红 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期327-332,共6页
Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In thi... Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field effects.We analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 theoretically.It is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ions.Furthermore,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates. 展开更多
关键词 lanthanum manganate the core level excitation spectra free-ion multiplet calculation oxidation state
原文传递
Facile in situ synthesis and characterization of Fe@Si/zeolite Na composites with magnetic core–shell structures from natural materials for enhanced curcumin loading capacity
19
作者 Munasir Nasir Nuhaa Faaizatunnisa +2 位作者 Muhammad Naufal Ariesta Lydia Rohmawati Rifqi Aulia Nurazizah 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期69-86,共18页
Curcumin is a natural polyphenol that is used in various traditional medicines.However,its inherent properties,such as its rapid degradation and metabolism,low bioavailability,and short half-life,are serious problems ... Curcumin is a natural polyphenol that is used in various traditional medicines.However,its inherent properties,such as its rapid degradation and metabolism,low bioavailability,and short half-life,are serious problems that must be resolved.To this end,a drug carrier incorporating natural magnetic cores in a zeolite framework was developed and applied to the loading of curcumin in ethanol solutions.In this system,curcumin is encapsulated in a zeolite Na(ZNA)magnetic core–shell structure(Fe@Si/ZNA),which can be easily synthesized using an in situ method.Synthesis of Fe_(3)O_(4) nanoparticles was carried out from natural materials using a co-precipitation method.Analysis of the prepared magnetic core–shell structures and composites was carried out using vibrating-sample magnetometery,Fourier transform infrared spectroscopy,transmission electron microscopy,and x-ray diffraction.The cumulative loading of curcumin in the ZNA composite with 9%nanoparticles was found to reach 90.70%with a relatively long half-life of 32.49 min.Stability tests of curcumin loading in the composite showed that adding magnetic particles to the zeolite framework also increased the stability of the composite structure.Adsorption kinetics and isotherm studies also found that the system follows the pseudo-second-order and Langmuir isotherm models. 展开更多
关键词 Zeolite Na Magnetic core–shell nanoparticles(MNPs) ZNA Adsorption CURCUMIN
下载PDF
矩阵对偶Core-EP逆性质的进一步研究
20
作者 魏佳艺 海国君 阿拉坦仓 《内蒙古大学学报(自然科学版)》 CAS 2024年第4期345-349,共5页
利用矩阵的Drazin逆以及Moore-Penrose逆描述了对偶Core-EP逆,并应用矩阵的Core-EP分解给出了对偶Core-EP逆的分块矩阵表达。受到EP矩阵的启发,得到了矩阵是k次对偶Core-EP矩阵的充要条件,并得到了一些矩阵为k次对偶Core-EP矩阵的结论。
关键词 广义逆 MOORE-PENROSE逆 DRAZIN逆 对偶core-EP逆 core-EP分解
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部