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Synthesis and Characterization of a Two-dimensional Cadmium(II) Compound Involving Covalent and Hydrogen Bonds

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Chinese Journal of Structural Chemistry 2004年第4期23卷 403-406页

作者： WANGRui-hu HANLei LINZheng-Zhong LUOJun-hua HONGMao-Chun StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

A two-dimensional hydrogen-bonded cadmium(II) compound [Cd(dapm)2- (CH3COO)2(H2O)2] (dapm = diaminodiphenylmethane) has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group C2/c with a = 27.572(3), b = 5.5064(5), c = 23.310(2) , = 124.785(1)o, C15H19Cdo.5ON2O3, Mr =331.52, V = 2906.6(5) ?, Z = 4, Dc = 1.515 g/cm3, F(000) = 1368 and = 0.801 mm-1. The final R = 0.0403 and wR = 0.1014 for 1795 observed reflections with I≥4(I). The centrosymmetric Cd(II) is six- coordinated in a distorted octahedral geometry, and the dapm in a trans mode acts as a monoden- tate ligand. The intermolecular hydrogen bonds among coordinated aqua molecules with coordi- nated acetate oxygen atoms and uncoordinated dapm nitrogen atoms form a two-dimensional supramolecular framework.

关键词： crystal structure hydrogen bonding cadmium complex

On the shepherding of Uranian epsilon ring

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Science China Mathematics 2000年第6期43卷 666-672页

作者：周济林孙义燧 Bambi hu Department of Astronomy Nanjing University Nanjing 210093 China Department of Physics and Center for Nonlinear studies Hong Kong Baptist University Hong Kong China Department of Astronomy Nanjing University Nanjing 210093 China Department of Physics and Center for Nonlinear studies Hong Kong Baptist UniversityHong KongChina Department of PhysicsUniversity of HoustonHouston TX 77204USA Correspondence should be addressed to Zhou Jilin

To explain the long-term existence of Uranian narrow rings, we study the dynamical evolution of Uranian epsilon ring under the influence of its two shepherding satellites: Cordelia and Ophelia. The model of planar-elliptic restricted three-body problem is employed, in which the three bodies are Uranus, a satellite and a test particle. Dissipations due to interparticle collisions are also taken into consideration. A mapping system has been obtained based on the differential equation system. Numerical results show that only those particles originally lying in the libration region of the resonance can be shepherded. The size of the libration region depends mainly on the orbital eccentricity and mass of the shepherd satellite. For the outer shepherd Ophelia with larger orbital eccentricity, if its mass is a third of the nominal mass 2.5 × 1019 g, most of the orbits are regular and the outer edge of the ring can be shepherded, but more fuzzy than the inner edge. Thus we infer that Ophelia has a smaller mass.

关键词： Uranian rings shepherding mechanism mapping approach.

Fine-Grained Ship Recognition Based on Visible and Near-Infrared Multimodal Remote Sensing Images: Dataset,Methodology and Evaluation

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Computers, Materials & Continua 2024年第6期79卷 5243-5271页

作者： Shiwen Song Rui Zhang Min hu Feiyao huang Department of Aerospace Science and Technology Space Engineering UniversityBeijing101416China

Fine-grained recognition of ships based on remote sensing images is crucial to safeguarding maritime rights and interests and maintaining national ***,with the emergence of massive high-resolution multi-modality images,the use of multi-modality images for fine-grained recognition has become a promising ***-grained recognition of multi-modality images imposes higher requirements on the dataset *** key to the problem is how to extract and fuse the complementary features of multi-modality images to obtain more discriminative fusion *** attention mechanism helps the model to pinpoint the key information in the image,resulting in a significant improvement in the model’s *** this paper,a dataset for fine-grained recognition of ships based on visible and near-infrared multi-modality remote sensing images has been proposed first,named Dataset for Multimodal Fine-grained Recognition of Ships(DMFGRS).It includes 1,635 pairs of visible and near-infrared remote sensing images divided into 20 categories,collated from digital orthophotos model provided by commercial remote sensing *** provides two types of annotation format files,as well as segmentation mask images corresponding to the ship ***,a Multimodal Information Cross-Enhancement Network(MICE-Net)fusing features of visible and near-infrared remote sensing images,has been *** the network,a dual-branch feature extraction and fusion module has been designed to obtain more expressive *** Feature Cross Enhancement Module(FCEM)achieves the fusion enhancement of the two modal features by making the channel attention and spatial attention work cross-functionally on the feature map.A benchmark is established by evaluating state-of-the-art object recognition algorithms on ***-Net conducted experiments on DMFGRS,and the precision,recall,mAP0.5 and mAP0.5:0.95 reached 87%,77.1%,83.8%and 63.9%,*** experiments demons

关键词： Multi-modality dataset ship recognition fine-grained recognition attention mechanism

NANOINDENTATION SIMULATION OF PE/POSS UNDER DIFFERENT SHAPES OF INDENTERS

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维普期刊数据库

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Acta Mechanica Solida Sinica 2011年第4期24卷 365-372页

作者： Enlai hu Yi Sun Fanlin Zeng Jianmin Qu Department of Astronautic Science and Mechanics Harbin Institute of TechnologyHarbin 150001China Northwestern University Department Civil & Environment EngineeringEvanstonIL 60208 USA

In this paper,the nanoindentation simulation on the two models of neat polyethylene（PE） and the polyethylene incorporated with 25wt% POSS（POSS-PE） is performed to reveal the reinforcing mechanism of the mechanical *** influence of the indenter shapes on nanoindentation is researched by using three different shapes of diamond indenters（cube-corner indenter,cylindrical indenter with spherical tip and cylindrical indenter with flat tip）.The molecular mechanics method is adopted to eliminate the temperature *** different indenters,the load-displacement responses,hardnesses（indentation hardness and Martens hardness） and Young＇s moduli of PE and POSS-PE are *** with PE,all the mechanical properties are improved ***,we analyze the source of loading drop phenomena and the enhancement mechanism of ***,the result shows that the different shapes of indenters cause a large impact on indentation hardness,but a little impact on Martens *** Young＇s modulus of the flat indenter is much larger than that of cube-corner indenter and spherical indenter.

关键词： molecular simulation nanoindentation shape of indenter hardness Young's mod-ulus

Disk Thicknesses and Some Parameters of 108 Non-Edge-On Spiral Galaxies

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 579-589页

作者： Tao hu Qiu-He Peng Hong-Shi Zong Department of Astronomy Nanjing University Nanjing 210093 Department of Physics Nanjing University Nanjing 210093 Department of Physics and Electronics Zhangzhou Normal University Zhangzhou 363000 Joint Astrophysics Center of Chinese Academy of Sciences-Peking University Beijing 100871 Open Laboratory of Cosmic Ray and High Energy Astrophysics Chinese Academy of Sciences Beijing 100039

We present disk thicknesses, some other parameters and their statistics of 108 nonedge-on spiral galaxies. The method for determining the disk thickness is based on solving Poisson＇s equation for a disturbance of matter density in three-dimensional spiral galaxies. From the spiral arms found we could obtain the pitch angles, the inclination of the galactic disk, and the position of the innermost point （the forbidden region with radius r0 to the galactic center） of the spiral arm, and finally the thickness.

关键词： galaxy: disk- galaxies: fundamental parameters- galaxies: spiral - galaxies:structure

The effect of axial stiffness of mooring lines on the horizontal motion of FDPSO

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 10-15页

作者： WEI YueFeng YANG JianMin CHEN Gang hu ZhiQiang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

FDPSO is a multifunction floating platform,which has the integral function of drilling,production,storage and offloading.A spread mooring system is adopted to position the *** coupled analysis in time domain for FDPSO system is conducted in the present paper,using the code *** effect of axial stiffness of the mooring line on the horizontal motion of FDPSO is studied by employing five types of different axial stiffness in the calculation of the motion response of FDPSO ***,the results of a model test conducted in the State Key Laboratory of Ocean Engineering in Shanghai Jiao Tong University are used to investigate the feasibility of the numerical method.

关键词： FDPSO motion performance mooring lines axial stiffness

Personalized Recommendation Algorithm Based on Preference Features

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Tsinghua Science and Technology 2014年第3期19卷 293-299页

作者： Liang hu Guohang Song Zhenzhen Xie Kuo Zhao the School of Computer Science and Technology Jilin University

A hybrid collaborative filtering algorithm based on the user preferences and item features is proposed.A thorough investigation of Collaborative Filtering （CF） techniques preceded the development of this *** proposed algorithm improved the user-item similarity approach by extracting the item feature and applying various item features＇ weight to the item to confirm different item *** preferences for different item features were obtained by employing user evaluations of the *** is expected that providing better recommendations according to preferences and features would improve the accuracy and efficiency of recommendations and also make it easier to deal with the data *** addition,it is expected that the potential semantics of the user evaluation model would be *** would explain the recommendation results and increase accuracy.A portion of the MovieLens database was used to conduct a comparative experiment among the proposed algorithms,i.e.,the collaborative filtering algorithm based on the item and the collaborative filtering algorithm based on the item *** Mean Absolute Error （MAE） was utilized to conduct performance *** experimental results show that employing the proposed personalized recommendation algorithm based on the preference-feature would significantly improve the accuracy of evaluation predictions compared to two previous approaches.

关键词： recommendation system collaborative filtering user preference

Single‑Atom Cobalt‑Based Electrochemical Biomimetic Uric Acid Sensor with Wide Linear Range and Ultralow Detection Limit

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Nano-Micro Letters 2021年第1期13卷 99-111页

作者： Fang Xin hu Tao hu Shihong Chen Dongping Wang Qianghai Rao Yuhang Liu Fangyin Dai Chunxian Guo Hong Bin Yang Chang Ming Li Institute of Materials Science and Devices Suzhou University of Science and TechnologySuzhou 215009People’s Republic of China Institute for Advanced Cross‑field Science and College of Life Science Qingdao UniversityQingdao 200671People’s Republic of China Institute for Clean Energy and Advanced Materials School of Materials and EnergySouthwest UniversityChongqing 400715People’s Republic of China School of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715People’s Republic of China Suzhou Institute of Biomedical Engineering and Technology Chinese Academy of SciencesSuzhou 215163People’s Republic of China State Key Laboratory of Silkworm Genome Biology College of BiotechnologySouthwest UniversityChongqing 400715People’s Republic of China

Uric acid(UA)detection is essential in diagnosis of arthritis,preeclampsia,renal disorder,and cardiovascular diseases,but it is very challenging to realize the required wide detection range and low detection *** present here a single-atom catalyst consisting of Co(Ⅱ)atoms coordinated by an average of 3.4 N atoms on an N-doped graphene matrix(A-Co-NG)to build an electrochemical biomimetic sensor for UA *** A-Co-NG sensor achieves a wide detection range over 0.4-41,950μM and an extremely low detection limit of 33.3±0.024 nM,which are much better than previously reported sensors based on various nanostructured ***,the A-Co-NG sensor also demonstrates its accurate serum diagnosis for UA for its practical *** of experimental and theoretical calculation discovers that the catalytic process of the A-Co-NG toward UA starts from the oxidation of Co species to form a Co^3+-OH-UA*,followed by the generation of Co^3+-OH+^*UA_H,eventually leading to N-H bond dissociation for the formation of oxidized UA molecule and reduction of oxidized Co^3+to Co^2+for the regenerated *** work provides a promising material to realize UA detection with wide detection range and low detection limit to meet the practical diagnosis requirements,and the proposed sensing mechanism sheds light on fundamental insights for guiding exploration of other biosensing processes.

关键词： Single-atom cobalt Nanozyme Biocatalysis Uric acid Molecular interaction

Cost-optimal Calculation for Ice-Storage Systems Using Neural Network

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Journal of Thermal Science 2002年第2期11卷 138-143页

作者： Zhihua hu huanqun Qian Haipeng Zhang Fangde Zhou Xi An Jiao Tong Univ State Key Lab Multiphase Flow Power Engn Xian 710049 Shaanxi Peoples R China

Based on the eminent characteristics of the ice-storage systems, which can shift cooling electrical demand from peak time to off peak time, this paper describes the ice storage air-conditioning system that is now used much frequently. The authors develop the operating cost model by simplification and introduce a neural network model and try to solve the optimal cost problem of operation by using this neural network model. In calculation, any trajectory of the neural network converges to its solution in finite time, which is consistent with result by simplex method. Comparing with different methods, the neural network is more effective, which can be alternative to simplex method in calculating the optimal cost model for ice storage air-conditioning systems.

关键词： ice-storage linear programming neural network.