检索结果-南通市图书馆

Implanting Ni into N-doped puffed carbon: A new advanced electrocatalyst for oxygen evolution reaction

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2020年第9期31卷 2230-2234页

作者： Feng cao Guoxiang Pan Yujian Zhang Xinhui Xia Department of Materials Chemistry Huzhou UniversityHuzhou 313000China State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang ProvinceDepartment of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

Tailored design and synthesis of high-quality electrocatalysts is vital for the advancement of oxygen evolution reaction(OER).Herein,we report a powerful puffing method to fabricate hierarchical porous N-doped carbon with numerous embedded Ni ***,during the puffing and annealing process,rice precursor with N and Ni sources can be in-situ converted into Ni-embedded N-doped porous carbon(N-PC/Ni) *** obtained N-PC/Ni composite possesses a cross-linked porous architecture containing conductive carbon backbone and active Ni nanoparticles electrocatalysts for *** pore formation in N-PC/Ni composite is also proposed because of carbothermic *** N-PC/Ni composite is fully studied as electrocatalysts for *** to increased active surface area,enhanced electronic conductivity and reactivity,the designed N-PC/Ni composite exhibits superior OER performance with a low Tafel slope(~88 mV/dec) and a low overpotential as well as excellent long-term stability in alkaline *** proposed rational design strategy may provide a new way to construct other advanced metal/heteroatom-doped composites for widespread application in electrocatalysis.

关键词： Oxygen evolution reaction Electrocatalysis Porous carbon Metal-carbon composites N doping

A novel method for vibration signal transmission and attenuation analysis in complex planetary gearboxes

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第9期67卷 2939-2953页

作者： WEI ChaoHu cao HongRui SHI JiangHai YANG Yang DU MingGang National and Local Joint Engineering Research Center of Equipment Operation Safety and Intelligent Monitoring Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China China North Vehicle Research Institute Beijing 100072China

Planetary gearboxes play a crucial role in altering rotary speed and transmitting power in large machines like wind turbines and sophisticated vehicles. There are many nonlinear interfaces, such as splines, bearings, and gear pairs, in planetary gearboxes, and the resulting vibration signal transmission and attenuation mechanisms are still unknown. In this study, a novel method for quantitatively analyzing the transmission and attenuation of vibration signals is proposed. A multibody dynamic model of the planetary gearbox considering nonlinear gear meshing is presented and experimentally validated. To avoid the interference of foundation vibration on the transmission of the fault signal, the fault impact factor(FIF) is used to describe the intensity of the failure, which aligns well with the experimental signals. Based on the FIF, the vibration signal attenuation of nonlinear interfaces such as splines, bearings, and gear meshing interfaces is quantitatively evaluated. To clarify the transfer paths of fault vibration signals inside the gearbox, the transfer path area method(TPAM) based on FIF is proposed. According to the simulated results,the primary transfer paths of fault vibration signals within the gearbox have been identified, which is of great help in understanding the transmission and attenuation of vibration signals in planetary gearboxes.

关键词： planetary gearbox nonlinear interface fault mechanism vibration transmission vibration attenuation

Experimental and analytical study on seismic behavior of steel-concrete multienergy dissipation composite shear walls

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2015年第1期14卷 125-139页

作者： Dong Hongying cao Wanlin Wu Haipeng Qiao Qiyun Yu Chuanpeng College of Architecture and Civil Engineering Beijing University of Technology

In this paper, a steel-concrete multi-energy dissipation composite shear wall, comprised of steel-reinforced concrete （SRC） columns, steel plate （SP） deep beams, a concrete wall and energy dissipation strips, is proposed. In order to study the multi-energy dissipation behavior and restorability after an earthquake, two stages of low cyclic loading tests were carded out on ten test specimens. In the first stage, test on five specimens with different number of SP deep beams was carried out, and the test lasted until the displacement drift reached 2%. In the second stage, thin SPs were welded to both sides of the five specimens tested in the first stage, and the same test was carried out on the repaired specimens （designated as new specimens）. The load-bearing capacity, stiffness, ductility, hysteretic behavior and failure characteristics were analyzed for both stages and the results are discussed herein. Extrapolating from these results, strength calculation models and formulas are proposed herein and simulations using ABAQUS carried out, they show good agreement with the test results. The study demonstrates that SRC columns, SP deep beams, concrete wall and energy dissipation strips cooperate well and play an important role in energy dissipation. In addition, this study shows that the shear wall has good recoverability after an earthquake, and that the welding of thin SP＇s to repair a deformed wall is a practicable technique.

关键词： steel reinforced concrete steel plate deep beam multi energy dissipation composite shear wall seismic behavior

Mathematical Model and Geometrical Model of Double Pitch ZN-type Worm Gear Set Based on Generation Mechanism

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2015年第3期28卷 549-555页

作者： SHU linsen cao Huajun LI Xianchong ZHANG Chenglong LI Yuxia State Key Laboratory of Mechanical Transmission Chongqing University

The current researches on the tooth surface mathematical equations and the theory of gearing mainly pay attention to the ordinary type worm gear set（e.g., ZN, ZA, or ZK）. The research of forming mechanism and three-dimensional modeling method for the double pitch worm gear set is not enough. So there are some difficulties in mathematical model deducing and geometry modeling of double pitch ZN-type worm gear set based on generation mechanism. In order to establish the mathematical model and the precise geometric model of double pitch ZN-type worm gear set, the structural characteristics and generation mechanism of the double pitch ZN-type worm gear set are investigated. Mathematical model of the ZN-type worm gear set is derived based on its generation mechanism and the theory of gearing. According to the mathematical model of the worm gear set which has been developed, a geometry modeling method of the double pitch ZN-type worm and worm gear is presented. Furthermore, a geometrical precision calculate method is proposed to evaluate the geometrical quality of the double pitch worm gear set. As a result, the maximum error is less than 6′10–4 mm in magnitude, thus the model of the double pitch ZN-type worm gear set is available to meet the requirements of finite element analysis and engineering application. The derived mathematical model and the proposed geometrical modeling method are helpful to guiding the design, manufacture and contact analysis of the worm gear set.

关键词： double pitch ZN-type worm gear set generation mechanism mathematical model geometrical model

Magnetism and superconductivity in Eu(Fe_(1-x)Ni_x)As_2(x= 0,0.04)

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2018年第12期61卷 37-44页

作者： YaBin Liu Yi Liu WenHe Jiao Zhi Ren GuangHan cao Department of Physics Zhejiang University Department of Physics Zhejiang University of Science and Technology Institute for Natural Sciences Westlake Institute for Advanced Study Collaborative Innovation Centre of Advanced Microstructures Nanjing University State Key Lab of Silicon Materials Zhejiang University

We report Eu-local-spin magnetism and Ni-doping-induced superconductivity(SC)in a 112-type ferroarsenide system Eu(Fe_(1-x)Ni_x)As_*** non-doped EuFeAs_2exhibits two primary magnetic transitions at ~100 and ~40 K,probably associated with a spin-density-wave(SDW)transition and an antiferromagnetic ordering in the Fe and Eu sublattices,*** additional successive transitions possibly related to Eu-spin modulations appear at 15.5 and 6.5 *** the Ni-doped sample with x=0.04,the SDW transition disappears,and SC emerges at T_c=17.5 *** Eu-spin ordering remains at around 40 K,followed by the possible reentrant magnetic modulations with enhanced spin ***,SC coexists with a weak spontaneous magnetization below 6.2 K in Eu(Fe_(0.96)Ni_(0.04))As_2,which provides a complementary playground for the study of the interplay between SC and magnetism.

关键词： superconductivity magnetism Ni doping iron-based superconductors Eu(Fe1-xNix)As2

Triggering mechanism and dynamic process of water-rock flow in Nanfen waste dump in 2010

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2021年第10期18卷 2565-2579页

作者： cao Chun-hui FENG Ji-li TAO Zhi-gang State Key Laboratory for Deep Geomechanics and Underground Engineering China University of Mining and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology BeijingBeijing 100083China

Water-rock flow is a kind of debris flow with more coarse particles and low viscosity, which occurs in many areas of the world. In this work, the water-rock flow that occurred on May 24, 2010, at Nanfen’s open-pit mine of China was investigated by combining field investigation, meteorological and hydrological survey with numerical simulation to understand its triggering mechanism and dynamic process. The field data shows that the short-term high-intensity rainfall is the most direct inducement to trigger water-rock flow in the waste dump. The loose shallow gravel soil and the V-shaped valley with a certain slope provide the necessary conditions of the occurrence of water-rock flow in the waste dump. Moreover, the possibility criterion of water-rock flow is presented by analyzing the historical rainfall data. In addition, the smoothed particle hydrodynamics(SPH) method was employed to simulate the waterrock flow under the conditions of Newtonian fluid with uniform distribution of water and coarse-grained materials. The simulating results show that the flow distance, velocity, shape, and deposition profile of water-rock flow are in good agreement with the field observation. The present work is beneficial to the risk assessment and mitigation design of water-rock flow disaster in the waste dump.

关键词： Water-rock flow Waste dump Triggering mechanism Smoothed particle hydrodynamics Rainfall intensity

Synthesis of porous hematite nanorods loaded with CuO nanocrystals as catalysts for CO oxidation

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2011年第6期20卷 669-676页

作者： Jianliang cao Yan Wang Tianyi Ma Yuping Liu Zhongyong Yuan Institute of New Catalytic Materials science Key Laboratory of Advanced Energy Materials Chemistry （Ministry of Education） College of Chemistry Nankai University Tianjin 300071 China

Porous hematite （α-Fe2O3） nanorods with the diameter of 20-40 nm and the length of 80-300 nm were synthesized by a simple surfactant-assisted method in the presence of cetyltrimethylammonium bromide （CTAB）.The α-Fe2O3 nanorods possess a mesostructure with a pore size distribution in the range of 5-12 nm and high surface area,exhibiting high catalytic activity for CO *** nanocrystals were loaded on the surface of porous α-Fe2O3 nanorods by a deposition-precipitation method,and the catalysts exhibited superior activity for catalytic oxidation of CO,as compared with commercial α-Fe2O3 powders supported CuO *** enhanced catalytic activity was attributed to the strong interaction between the CuO nanocrystals and the support of porous α-Fe2O3 nanorods.

关键词： porous materials iron oxide nanostructures CuO supported nanocatalysts catalytic CO oxidation

DMFVAE:miRNA-disease associations prediction based on deep matrix factorization method with variational autoencoder

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2024年第6期18卷 259-270页

作者： Pijing WEI Qianqian WANG Zhen GAO Ruifen cao Chunhou ZHENG Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Key Lab of Intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and TechnologyAnhui UniversityHefei 230601China Key Lab of Intelligent Computing and Signal Processing of Ministry of Education School of Artificial IntelligenceAnhui UniversityHefei 230601China

MicroRNAs(miRNAs)are closely related to numerous complex human diseases,therefore,exploring miRNA-disease associations(MDAs)can help people gain a better understanding of complex disease *** increasing number of computational methods have been developed to predict ***,the sparsity of the MDAs may hinder the performance of many *** addition,many methods fail to capture the nonlinear relationships of miRNA-disease network and inadequately leverage the features of network and neighbor *** this study,we propose a deep matrix factorization model with variational autoencoder(DMFVAE)to predict potential *** first decomposes the original association matrix and the enhanced association matrix,in which the enhanced association matrix is enhanced by self-adjusting the nearest neighbor method,to obtain sparse vectors and dense vectors,***,the variational encoder is employed to obtain the nonlinear latent vectors of miRNA and disease for the sparse vectors,and meanwhile,node2vec is used to obtain the network structure embedding vectors of miRNA and disease for the dense ***,sample features are acquired by combining the latent vectors and network structure embedding vectors,and the final prediction is implemented by convolutional neural network with channel *** evaluate the performance of DMFVAE,we conduct five-fold cross validation on the HMDD v2.0 and HMDD v3.2 datasets and the results show that DMFVAE performs ***,case studies on lung neoplasms,colon neoplasms,and esophageal neoplasms confirm the ability of DMFVAE in identifying potential miRNAs for human diseases.

关键词： miRNA-disease association deep matrix factorization self-adjusted nearest neighbor variational encoder network structure

Self-assembly of porphyrins on perovskite film for blade-coating stable large-area methylammonium-free solar cells

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第8期34卷 306-310页

作者： Taorui Liu Yajun Liu Xingbang Gao Jing cao State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Phase transition and phase separation of formamidinium-cesium(FA-Cs)perovskite during the fabrication and operation processes reduce the efficiency and stability of perovskite solar cells(PSCs).Here,we develop an in situ molecular self-assembly approach on perovskite surface using an amine nickel porphyrin(NiP).The NiP doped perovskite precursor solution was deposited on substrate by blade-coating under ambient *** molecules self-assemble into supramolecule bound on perovskite surface during the vacuum-assisted *** a modification controls the perovskite grain growth to generate the uniform perovskite *** supramolecule can release the residual lattice strain to inhibit the phase transition of perovskite film,and promote the charge extraction and transport to suppress the phase separation of FA-Cs perovskite during long-term illumination ***,the best efficiency of large-area NiP-based FA-Cs-PSCs with the active area of 1.0 cm2 is up to 20.3%(certified as 19.2%),which is close to the record efficiency(20.37%)by *** NiP-doped device reveals the remarkably improved overall *** work affords a novel way to address the phase transition and phase separation in FA-Cs perovskite.

关键词： MA-free perovskite Ni porphyrin Supramolecule Self-assemble Phase transition Phase separation