检索结果-南通市图书馆

A Fully Implicit Finite Difference Scheme for the Variable-Order Fractional Advection-Diffusion Equation with a Nonlinear Source Term

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Fully Implicit Finite Difference Scheme for the Variable-O...

Effect of low-speed waterjet pressure on the rock-breaking performance of unsubmerged cavitating abrasive waterjet

第二届国际计算科学与工程国际学术研讨会

作者： Wei-yuan Ma Ya-bin Shao hai-dong zhang School of Mathematics and Computer Science Northwest University for Nationalities

This paper proposes a finite difference scheme for variable-order nonlinear fractional diffusion equation, in which the nonlinear source term is considered implicit. A linear iterative algorithm for nonlinear scheme is introduced. The stability and convergence of the method are proved by discrete energy method. The convergence order of the method is O （ h）. Some examples demonstrate that the method is efficient and reliable.

关键词： Variable-order nonlinear fractional diffusion equation Fully implicit difference scheme Iterative algorithm Convergence Stability

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Petroleum Science 2024年第04期21卷 2638-2649页

作者： Chen-Xing Fan Deng Li Yong Kang hai-Tao zhang Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan University School of Power and Mechanical Engineering Wuhan University

Unsubmerged cavitating abrasive waterjet(UCAWJ) has been shown to artificially create a submerged environment that produces shear cavitation, which effectively enhances rock-breaking performance. The shear cavitation generation and collapse intensity depend on the pressure difference between the intermediate high-speed abrasive waterjet and the coaxial low-speed waterjet. However, the effect of the pressure of the coaxial low-speed waterjet is pending. For this purpose, the effect of low-speed waterjet pressure on rock-breaking performance at different standoff distances was experimentally investigated,and the effects of erosion time and ruby nozzle diameter on erosion performance were discussed. Finally,the micromorphology of the sandstone was observed at different locations. The results show that increased erosion time and ruby nozzle diameter can significantly improve the rock-breaking performance. At different standoff distances, the mass loss increases first and then decreases with the increase of low-speed waterjet pressure, the maximum mass loss is 10.4 g at a low-speed waterjet pressure of0.09 MPa. The surface morphology of cavitation erosion was measured using a 3D profiler, the increase in both erosion depth and surface roughness indicated a significant increase in the intensity of the shear cavitation collapse. At a low-speed waterjet pressure of 0.18 MPa, the cavitation erosion surface depth can reach 600 μm with a roughness of 127 μm.

关键词： Rock-breaking Coaxial low-speed waterjet pressure Abrasive waterjet Cavitation Unsubmerged environment

Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2024年第3期12卷 444-455页

作者： WEN-JIN zhang HAO-CHANG MO WEN-JIE CHEN XIAO-dong CHEN JIAN-WEN dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

The RFI Fast Mitigation Algorithm Based on Block LMS Filter

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第1期24卷 265-272页

作者： Han Wu hai-Long zhang Ya-Zhou zhang Jie Wang Xu Du Ting zhang Xin-Chen Ye Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China

The radio telescope possesses high sensitivity and strong signal collection *** receiving celestial radiation signals,it also captures Radio Frequency Interferences(RFIs)introduced by human ***,as signals originating from sources other than the astronomical targets,significantly impacts the quality of astronomical *** paper presents an RFI fast mitigation algorithm based on block Least Mean Square(LMS)*** enhances the traditional adaptive LMS filter by grouping L adjacent time-sampled points into one block and applying the same filter coefficients for filtering within each *** transformation reduces multiplication calculations and enhances algorithm efficiency by leveraging the time-domain convolution *** algorithm is tested using baseband data from the Parkes 64 m radio telescope's pulsar observations and simulated *** results confirm the algorithm's effectiveness,as the pulsar profile after RFI mitigation closely matches the original pulsar profile.

关键词： methods:data analysis techniques:interferometric (stars:)pulsars:individual(J0437-4715)

High-throughput calculation-based rational design of Fe-doped MoS_(2) nanosheets for electrocatalytic p H-universal overall water splitting

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第4期91卷 194-202页

作者： Guangtong hai Xiangdong Xue Zhenyu Wu Canyang zhang Xin Liu Xiubing Huang Institute of Zhejiang University-Quzhou Zhejiang UniversityQuzhou 324000ZhejiangChina Beijing Key Laboratory of Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and TechnologyBeijing 100083China CentreÉnergie Matériaux et Télécommunications(EMT) Institut national de la recherche scientifique(INRS)Varennes J3X1P7QuébecCanada

Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheets(SFe-DMNs)were prepared based on the high-throughput density functional theory(DFT)calculation *** to the synergistic effect between Fe atom and MoS_(2)and optimized intermediate binding energy,the SFe-DMNs could deliver outstanding activity for both HER and *** assembled into a two-electrode electrolytic cell,the SFe-DMNs could achieve the current density of 50 mA cm^(-2)at a low cell voltage of 1.55 V under neutral *** results not only confirmed the effectiveness of high-throughput screening,but also revealed the excellent activity and thus the potential applications in fuel cells of SFe-DMNs.

关键词： High-throughput calculation Overall water splitting Single atom doped catalyst Molybdenum disulfide nanosheet

Salinity effect-induced ENSO amplitude modulation in association with the interdecadal Pacific Oscillation

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第4期42卷 1019-1036页

作者： hai ZHI Xiaokun WANG Rong-Hua zhang Pengfei LIN Jifeng QI College of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laoshan Laboratory Qingdao 266237China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China

A 110-year ensemble simulation of an ocean general circulation model(OGCM)was analyzed to identify the modulation of salinity interdecadal variability on El Niño-Southern Oscillation(ENSO)amplitude in the tropical Pacific during *** simulating results show that sea surface salinity(SSS)variation in the region exhibits notable and coherent interdecadal variability signal,which is closely associated with the Interdecadal Pacific Oscillation(IPO).As salinity increases or reduces,the SSS modulations on ENSO amplitude during its warm/cold events vary asymmetrically with positive/negative IPO ***,salinity interdecadal variability can enhance or reduce ENSO-related conditions in upper-ocean stratification,contributing noticeably to ENSO *** anomalies associated with the mixed layer depth and barrier layer thickness can modulate ENSO amplitude during positive and negative IPO phases,resulting in the asymmetry of sea surface temperature(SST)anomaly in the tropical *** positive IPO phases,SSS interdecadal variability contributes positively to El Niño amplitude but negatively to La Niña amplitude by enhancing or reducing SSS interannual variability,and vice versa during negative IPO ***,the results indicate that the modulation of the ENSO amplitude by the SSS interdecadal variability is 15%-28%during negative IPO phases and 30%-20%during positive IPO phases,***,the SSS interdecadal variability associated with IPO and its modulation on ENSO amplitude in the tropical Pacific are among factors essentially contributing ENSO diversity.

关键词： El Niño-Southern Oscillation(ENSO)amplitude Interdecadal Pacific Oscillation(IPO) ocean salinity variability tropical Pacific upper-ocean stratification

Transverse mode-coupling instability with longitudinal impedance

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： hai-Sheng Xu Chun-Tao Lin Na Wang Jing-Ye Xu Yuan zhang Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEPC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

同方期刊数据库

Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

在线全文

学校读者我要写书评

暂无评论

Tungsten 2024年第3期6卷 585-595页

作者： hai-Qi zhang Xiao-Jun Zeng Qing-Qing zhang Zu-Liang zhang Chu-Long Jin Rong-hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Microstructure in Ni80 Fe20/Cu magneticmultilayers and spin valve

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

电子显微学报 2000年第1期 17-25页

作者： WANG Wen\|dong\ SUN hai\|ping\ zhang Ze (Beijing Laboratory of Electron Microscopy,Institute of Physics,Chinese Academy of Sciences,Beijing,100080,P.R.China)

用高分辨电子显微学及平行电子能量损失谱方法研究了Ni80Fe20Cu基磁性多层膜和自旋阀的显微结构。高分辨像显示,磁性多层膜及自旋阀均具有沿薄膜生长方向的柱晶结构。Ni,Fe,Cu和Mn元素的成分分布图显示,柱晶内仍保持完整的层状结构。沿... 详细信息

用高分辨电子显微学及平行电子能量损失谱方法研究了Ni80Fe20Cu基磁性多层膜和自旋阀的显微结构。高分辨像显示,磁性多层膜及自旋阀均具有沿薄膜生长方向的柱晶结构。Ni,Fe,Cu和Mn元素的成分分布图显示,柱晶内仍保持完整的层状结构。沿薄膜生长方向的自旋阀元素分布曲线分析表明,NiFe层中的Ni元素沿柱晶晶界向相邻Cu层扩散。讨论了这些低维磁电子学材料的显微结构对磁输运性能的影响。

关键词： Fe 磁性多层膜显微结构柱晶薄膜生长晶体生长高分辨电子显微学自旋阀 Cu magneticmultilayers and spin valve