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Chinese Science Bulletin 2006年第8期51卷 994-999页

作者： PING Fan LUO Zhexian JU Jianhua Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information Science & Technology Nanjing 210044 China China Meteorological Administration training center Beijing 100081 China

The rainfall over the Yangtze River val- ley during flood seasons (June to July) shows both interannual and decadal variations. The rainfall has been increasing since 1990, showing a decadal sig- nal. The variations of rainfall are influenced by the multi-scale interactions in the atmosphere-ocean coupled climate system. The rainfall, SST, and cir- culation are analyzed with the Chinese 160 station data, and other observational/reanalysis data, re- spectively. The separation between the interannual and decadal variations is carried out. The key areas affecting the Yangtze rainfall are the western Pacific warm pool on the interannual time scale and the EINO3 area on the decadal time scale, respectively. The circulation anomaly associated with the interan- nual variation occurs in the upper troposphere whereas that associated with the decadal variation appears in the lower troposphere.

关键词：长江流域降雨量动力学因素比较分析

Review of computer-generated hologram algorithms for color dynamic holographic three-dimensional display

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Light(Science & Applications) 2022年第9期11卷 1962-1978页

作者： Dapu Pi Juan Liu Yongtian Wang Beijing engineering Research center for Mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China

Holographic three-dimensional display is an important display technique because it can provide all depth information of a real or virtual scene without any special *** recent years,with the development of computer and optoelectronic technology,computer-generated holograms have attracted extensive attention and developed as the most promising method to realize holographic ***,some bottlenecks still restrict the development of computer-generated holograms,such as heavy computation burden,low image quality,and the complicated system of color holographic *** overcome these problems,numerous algorithms have been investigated with the aim of color dynamic holographic three-dimensional *** this review,we will explain the essence of various computer-generated hologram algorithms and provide some insights for future research.

关键词： holographic dynamic overcome

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang Jiang Hui-ting Zheng Fei Liu Hai-dong Zhao National engineering Research center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Simulation research on the energy dissipation and shock absorption performance of a swing column device based on fuzzy control

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Earthquake engineering and engineering Vibration 2022年第4期21卷 987-998页

作者： Zheng Yong Yuan Bo Research center of Space Structures Guizhou UniversityGuiyang 550004China College of Civil engineering Guizhou UniversityGuiyang 550004China Key Laboratory of Structural engineering of Guizhou Province Guiyang 550025China

Double-column bridge piers are prone to local damage during earthquakes,leading to the destruction of *** improve the earthquake resistance of double-column bridge piers,a novel swing column device(SCD),consisting of a magnetorheological(MR)damper,a current controller,and a swing column,was designed for the present *** verify the seismic energy dissipation ability of the SCD,a lumped mass model for a double-column bridge pier with the SCD was established according to the low-order modeling method proposed by ***,the motion equation of the double-column bridge pier with the SCD was established based on the D′Alembert principle and solved with the use of computational *** was found that the displacement response of the double-column bridge pier was effectively controlled by the ***,due to rough current selection and a time delay,there is a significant overshoot of the bridge acceleration using ***,to solve the overshoot phenomenon,a current controller was designed based on fuzzy logic *** was found that the SCD design based on fuzzy control provided an ideal shock absorption effect,while reducing the displacement and acceleration of the bridge pier by 36.43%‒40.63%and 30.06%‒33.6%,respectively.

关键词： swing column device double-column bridge pier fuzzy control MR damper structural control low-element modeling method

A highly sensitive luminescent metal-organic framework thermometer for physiological temperature sensing

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Journal of Rare Earths 2018年第6期36卷 561-566页

作者： Lin Zhang Yadan Xie Tifeng Xia Yuanjing Cui Yu Yang Guodong Qian State Key Laboratory of Silicon Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Materials Science and EngineeringZhejiang University

Thermal sensing and imaging in the physiological temperature range are of great importance for studying physiological processes and treating diseases. Metal-organic frameworks(MOFs) exhibit great promise for developing luminescent thermometers due to their remarkable structural diversities and tunable luminescence properties. Here, we synthesized a series of luminescent mixed-lanthanide MOFs,EuTbBPT(x = 0.019, 0.058, 0.106; H3 BPT = biphenyl-3,4’,5-tricarboxylate acid) and adopted powder X-ray diffraction(PXRD), thermogravimetric analysis(TGA) and Fourier transform infrared(FT-IR) to characterize the resulting products. The temperature-dependent photoluminescence emission spectra were recorded to investigate their potential applications in physiological temperature readout. It is found that the intensity ratio of Tbto Euis linearly correlated with temperature and the relative sensitivity is higher than 1.5%/℃ over the entire physiological temperature range. Furthermore,the temperaturedependent luminescence color emission allows for visual colorimetric temperature *** lifetime testing and triplet energy level measurement were further conducted to study the mechanism.

关键词： Lanthanide metal-organic frameworks Luminescent thermometer Ratiometric Colorimetric High sensitivity Physiological temperature

Water in the Neck-Zipper Region of Kinesin

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Chinese Physics Letters 2009年第7期26卷 376-379页

作者：黄艳宾潘章张辉安莉孔德信纪青 School of Science Hebei University of Engineering Handan 056038 School of Science Hebei University of Technology Tianjin 300130 Basic Courses Department Tangshan College Tangshan 063000 Shandong Provincial Research center for Bioinformatlc engineering and Technique Center for Advanced Study Shandong University of Technology Zibo 255049

Neck linker （NL） is one of the most important mechanical elements of kinesin motors. The zipping up process of the neck-zipper （NZ） formed by NL and the related secondary structure elements is one of the major parts of kinesin＇s power stroke. All the weak interactions that are responsible for the formation of NZ are sensitive to or dependent on water. To investigate the role of water in the NZ region, a molecular dynamics （MD） model is set up with a crystal structure of kinesin 2KIN surrounded by a 10 A water layer, and minimization is performed to determine the positions of hydrogen atoms and other atoms. It is revealed that water molecules can assist the docking process of NL by forming hydrogen bonds at those positions where direct hydrogen bonding between the two sides of NZ is hindered and then acts as a constructive component of NZ at the docked state of NL. This result may improve the understanding of the mechanism for the docking of NL of kinesin wherein the function of water has not been comprehended sufficiently.

关键词： Biological physics

Isothermal oxidation behavior and mechanism of a nickel-based superalloy at 1000°C

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 776-783页

作者： Zhi-yuan Zhu Yuan-fei Cai You-jun Gong Guo-ping Shen Yu-guo Tu Guo-fu Zhang School of Material Science and engineering Jiangsu University of Science and Technology Technology center Jiangsu Shenyuan Special Steel Co.Ltd

The oxidation behavior of a nickel-based superalloy at 1000°C in air was investigated through X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy analysis. A series of oxides, including external oxide scales（Cr_2O_3,（TiO_2 ＋ Mn Cr_2O_4）） and internal oxides（Al_2O_3,Ti N）, were formed on the surface or sub-surface of the substrate at 1000°C in experimental still air. The oxidation resistance of the alloy was dependent on the stability of the surface oxide layer. The continuity and density of the protective Cr_2O_3 scale were affected by minor alloying elements such as Ti and Mn. The outermost oxide scale was composed of TiO_2 rutile and Mn Cr_2O_4 spinel, and the growth of TiO_2 particles was controlled by the outer diffusion of Ti ions through the pre-existing oxide layer. Severe internal oxidation occurred beneath the external oxide scale, consuming Al and Ti of the strength phase γ′（Ni_3（Al,Ti）） and thereby severely deteriorating the surface mechanical properties. The depth of the internal oxidation region was approximately 35 μm after exposure to experimental air at 1000°C for 80 h.

关键词： nickel-based superalloy isothermal oxidation oxide scale internal oxidation

High-precision analytical solutions for Earth coverage of constellation equipped with reentry glide vehicles

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Chinese Journal of Aeronautics 2024年第9期37卷 385-398页

作者： Ping MA Weibo SUN Jie GAO Tao CHAO Control and Simulation center Harbin Institute of TechnologyHarbin 150001China Beijing Institute of Spacecraft System engineering Beijing 100094China

To efficiently and accurately design satellite constellations equipped with Reentry Glide Vehicles(RGVs),new analytical solutions are developed for calculating their coverage ***,a new coverage model is established by approximating the Reentry Reachable Domain(RRD).However,the computation of real-time relative distances between satellites and targets,which is essential for coverage analysis based on this model,imposes a significant compu-tational *** address this challenge,a coverage analysis method based on two-dimensional map theory is *** method represents the coverage conditions of a target as a fixed area on a two-dimensional map and transforms the satellite trajectory into a series of parallel *** determining the intersection points between these lines and the area boundaries,the coverage ana-lytical solutions for a target point are *** this basis,coverage theorems are presented for rapid calculation of the constellation coverage performance for an *** results demon-strate the effectiveness and high precision of the proposed analytical solutions.

关键词： Constellation Analytical solutions Reentry glide vehicle Reentry reachable domain Two-dimensional map

Modulating morphology via side-chain engineering of fused ring electron acceptors for high performance organic solar cells

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Science China Chemistry 2019年第6期62卷 790-796页

作者： Fuwen Zhao Dan He Jingming Xin Shuixing Dai Han Xue Li Jiang Zhixiang Wei Wei Ma Xiaowei Zhan Yongfang Li Chunru Wang Institute of Chemistry Chinese Academy of Sciences State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Department of Materials Science and engineering College of Engineering Peking University National center for Nanoscience and Technology

In this work, four fused ring electron acceptors(FREAs), 2F-C5, 2F-C6, 2F-C8 and 2F-C10, are developed to investigate the effect of side-chain size on the molecular properties and photovoltaic performance of FREA systematically. The elongation of side-chains in the FREAs not only improves their solubility in the processing solvent, but also enhances their miscibility with the donor PBDB-T. It helps the FREA diffuse into the donor PBDB-T during film-formation, thus leading to the decrease in domain size and domain purity from PBDB-T:2F-C5 to PBDB-T:2F-C10 blend films in sequence. The smaller domain size affords more D/A interfaces to benefit exciton dissociation and inhibit monomolecular recombination. However, severe bimolecular recombination occurs when the domain purity decreases to a critical point. Due to the dual function of the increment of side-chain length, both short-circuit current density(J_(SC)) and fill factor(FF) of devices exhibit an evolution of first increasing then decreasing from 2F-C5, 2F-C6, 2F-C8 to 2F-C10 based OSCs. The PBDB-T:2F-C8 based OSCs get a fine balance in morphology with moderate domain size as well as high domain purity simultaneously for the least charge carrier recombination, thus achieving the highest power conversion efficiency of 12.28% with the best J_(SC)(21.27 mA cm^(-2)) and FF(71.96%).

关键词： solar cells fused ring electron acceptor side-chain length morphology

EABDS: Attribute-Based Secure Data Sharing with Efficient Revocation in Cloud Computing

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Chinese Journal of Electronics 2015年第4期24卷 862-868页

作者： HUANG Qinlong MA Zhaofeng YANG Yixian FU Jingyi NIU Xinxin Information Security center Beijing University of Posts and Telecommunications National engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and Telecommunications

Ciphertext-policy attribute-based encryption(CP-ABE) is becoming a promising solution to guarantee data security in cloud computing. In this paper,we present an attribute-based secure data sharing scheme with Efficient revocation(EABDS) in cloud *** scheme first encrypts data with Data encryption key(DEK) using symmetric encryption and then encrypts DEK based on CP-ABE, which guarantees the data confidentiality and achieves fine-grained access control. In order to solve the key escrow problem in current attribute based data sharing schemes, our scheme adopts additively homomorphic encryption to generate attribute secret keys of users by attribute authority in cooperation with key server, which prevents attribute authority from accessing the data by generating attribute secret keys *** scheme presents an immediate attribute revocation method that achieves both forward and backward *** computation overhead of user is also reduced by delegating most of the decryption operations to the key *** security and performance analysis results show that our scheme is more secure and efficient.

关键词： Attribute-based encryption Data sharing Attribute revocation Key escrow Cloud computing