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Full-Range Compressive Stress-Strain Curves for Cold-Formed 304 Stainless Steel Circular Hollow Sections After Exposure to Vacuum Brazing

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Acta Mechanica Solida Sinica 2018年第5期31卷 557-572页

作者： bin Hu Yang jin Lin-Zhi Wui Center for Composite Materials Harbin Institute of Technology Harbin 150001 China Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil Engineering Harbin Engineering University Harbin 150001 China

With the rapid development of microscale cellular structures, the small-diameter cold-formed welded stainless steel tubes have recently been used for creating the metallic lat- tice topologies with high mechanical properties. In this paper, to obtain the accurate material properties of the circular hollow section （CHS） under pure compression, a series of concentric compression tests are conducted on the millimeter-scale cold-formed 304 stainless steel circu- lar tubular stub columns after exposure to a vacuum brazing process. The tests cover a total of 18 small-diameter stub tubes with measured thickness-to-diameter ratios （t/D） from 0.023 to 0.201. A generalized three-stage nominal stress-strain model is developed for describing the compressive behavior of the post-brazing CHSs over the full strain range. This mechanical model is especially applicable to computer code implementation. Hence, an interactive computer pro- gram is developed to simultaneously optimize three strain hardening exponents （n1, n2, n3） in the expression of the model to produce the stress-strain curve capable of accurately replicating the test data. To further reduce the number of the model and material parameters on which this model depends, this paper also develops five expressions for determining the 2.5% proof stress （ap2）, n2, the ultimate compressive strength （σp3）, n3, and the ultimate plastic strain （p3%） for given experimental values of three basic material parameters （E0, σ0.01, σ0.2）. These expressions are validated to he effective for the CHSs with t/D 〉_ 0.027. The analytically predicted full-range stress-strain curves have generally shown close agreement with the ones obtained experimentally.

关键词： Compression test Stress-strain curve Cold-formed 304 Stainless steel Circular hollow section (CHS) Post-brazing

Effect of Cl- Concentration on the SCC Behavior of 13Cr Stainless Steel in High-Pressure CO2 Environment

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1459-1469页

作者： jin-jin Zhao Xian-bin Liu Shuai Hu En-Hou Han National Engineering Center for Corrosion Control Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

An effect of Cl-concentration on the stress corrosion cracking(SCC)behavior of 13 Cr stainless steel was investigated by employing electrochemical measurements and the slow strain rate tensile *** tests were conducted in various solutions with different concentrations of NaCl at 90℃ under 3 MPa CO2 with 3 MPa *** results indicate that the passive film of the specimen formed in the 10% NaCl solution has the best protective effect on the *** SCC susceptibility does not increase with increasing the chloride ion concentration,the lowest SCC susceptibility occurs when the NaCl concentration is 10%,and the specimens show higher SCC susceptibility in the 5% NaCl and 20% NaCl solutions.

关键词： 13Cr Cl- Stress corrosion cracking CO2 environment

Time-domain channel estimator based on cyclic correlationfor OFDM systems with guard interval

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 26-31页

作者： IM Se-bin CHOI Hyung-jin Communication Research Center Harbin Institute of Technology

Channel impulse response （CIR） can be estimated on the basis of cyclic correlation in time-domain for orthogonal frequency division multiplexing （OFDM） systems, This article proposes a generalized channel estimation method to reduce the estimation error by taking the average of different CIRs. Channel impulse responses are derived according to the different starting points of cyclic correlation. In addition, an effective CIR length estimation algorithm is also presented. The whole proposed methods are more effective to OFDM systems, especialiy to those with longer cyclic prefix. The analysis and the simulation results verify that the mean square error performance is 4-5 dB better than the conventional schemes under the same conditions.

关键词： CIR OFDM channel estimation mean squareerror (MSE)

An Improved Feasible QP-free Algorithm for Inequality Constrained Optimization

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Acta Mathematica Sinica,English Series 2012年第12期28卷 2475-2488页

作者： Zhi bin ZHU jin Bao JIAN College of Mathematics and Computing Science Guilin University of Electronic Technology College of Mathematics and Informational Science Guangxi University College of Mathematics and Informational Science Yulin Normal University

In this paper, an improved feasible QP-free method is proposed to solve nonlinear inequality constrained optimization problems. Here, a new modified method is presented to obtain the revised feasible descent direction. In view of the computational cost, the most attractive feature of the new algorithm is that only one system of linear equations is required to obtain the revised feasible descent direction. Thereby, per single iteration, it is only necessary to solve three systems of linear equations with the same coefficient matrix. In particular, without the positive definiteness assumption on the Hessian estimate, the proposed algorithm is still global convergence. Under some suitable conditions, the superlinear convergence rate is obtained.

关键词： Inequality constrained optimization feasible QP-free method system of linear equations,global convergence superlinear convergence rate

Structure of a Phase-Separating System in the Presence of Oscillatory Particles

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Communications in Theoretical Physics 2004年第5X期42卷 773-778页

作者： HUANGFu-bin ZHUYue-jin LOUSen-Yue physicsDepartment ShanghaiJiaoTongUniversityShanghai200030China physicsDepartment NingboUniversityNingbo315211China

We numerically simulate the processing of the phase separation of the polymer blend-particle system under fluctuating fields by new discretization's form. Due to the presence of oscillatory particles which have an affinity for one of the components, the ordering mechanism of phase separation will be changed. By changing the oscillatory frequency ω and amplitude γ, we can find the formation of the striped structures either parallel or perpendicular to the oscillatory direction and obtain a diagram describing the orientational ordering of the domain structures.

关键词：共混聚合物相位独立性薄膜材料动力学结构

Painleve Nonstandard Truncation Expansion Solutions of Dynamics Equation ofDiblock Copolymer

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Communications in Theoretical Physics 2005年第3期43卷 561-566页

作者： QIANXian-Min ZHUYue-jin HUANGFu-bin physicsDepartment ShanghaiJiaoTongUniversityShanghai200030China／／physicsDepartmentShaoxingCollegeofArtsandSciencesShaoxing312000China PhysicsDepartment NingboUniversityNingbo315211China PhysicsDepartment ShanghaiJiaoTongUniversityShanghai200030China

Through Pickering's and extended Painleve nonstandard truncated expansionmethod, this paper solves the phase-separating dynamics equation of diblock copolymer, and obtainsvarious exact solutions. We discuss non-comple... 详细信息

关键词： Painleve nonstandard truncated expansion phase separation diblockcopolymer hyperbolic function elliptic function

Plasmonic CsPbBr_(3)–Au nanocomposite for excitation wavelength dependent photocatalytic CO_(2) reduction

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Journal of Energy Chemistry 2021年第2期30卷 309-315,I0011页

作者： jin-Feng Liao Ya-Ting Cai Jun-Yan Li Yong Jiang Xu-Dong Wang hong-Yan Chea Dai-bin Kuang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510217GuangdongChina

The optoelectronic performance of CsPbBr_3 nanocrystal(NC) has been dramatically limited by the severe charge carrier recombination and its narrow light absorption range,which are anticipated to be resolved via coupling with plasmonic Au nanoparticle(NP).In view of this,CsPbBr_3-Au nanocomposite is fabricated and further employed as a concept model to study the electronic interaction between perovskite NC and Au NP for the first *** has been found that the excitation-wavelength dependent carrier transfer behavior exists in CsPbBr_3-Au *** illumination with visible light(λ>420 nm),photo-generated electrons in CsPbBr_3 can inject into Au with an electron injection rate and efficiency of 2.84×10~9 s^(-1) and 78%,*** boosted charge separation is further translated into a 3.2-fold enhancement in CO_2 photocatalytic reduction activity compared with pristine CsPbBr_*** the other hand,when solely exciting Au NP with longer wavelength light(λ>580 nm),the localized surface plasmon resonance(LSPR) induced hot electrons in Au NPs can transfer to CsPbBr_3 NC and further participate in photocatalytic reaction towards CO_2 *** present study provides new insights into preparing plasmonic nanostructure to enhance the performance of perovskite based optoelectronic devices.

关键词： Perovskite Gold nanoparticle Photocatalysis Localized surface plasmon resonance

Application of pole-zero cancellation circuit in nuclear signal filtering and shaping algorithm

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Nuclear Science and Techniques 2021年第8期32卷 85-94页

作者： Huai-Ping Wang Jian-bin Zhou Xiao-Ping Ouyang Xian-Guo Tuo Xu hong Yi Liu Jie Yu You-Xian jin College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyNo.1 East 3 RoadErxian BridgeChenghua DistrictChengdu 610059China Northwestern Institute of Nuclear Technology Xi’an 710024China Engineering Research Center of Nuclear Technology Application(East China University of Technology) Ministry of EducationNanchang 330013China

In radiation measurement and digital nuclear spectrum systems,traditional nuclear signal processing circuits in nuclear electronics have been gradually replaced by digital algorithm modules with the application of highperformance programmable hardware logic devices(such as FPGA or DSP).Referring to the digital realization method of inverse RC integral circuit systems,the function of the pole-zero cancellation(PZC)circuit was analyzed,a new modified cascade equivalent model of PZC was established,and the time-domain digital PZC(DPZC)recursive algorithm was derived in detail in this *** parameters kIand k_(D)are included in the new algorithm,where kIshould match the exponential decay time constant of the input signal to realize the pole-zero compensation,while the decay time constant of the output signal can be changed with the adjustable parameter k_(D)(which is larger than the decay time constant of the input signal).Based on the new DPZC algorithm module,two trapezoidal(triangular)shaping filters were designed and *** amplitude–frequency characteristics of the output signal of the proposed trapezoidal shaping algorithm and the convolution trapezoidal shaping algorithm were compared,with fixed peaking *** results show that the trapezoidal shaping algorithm based on DPZC can better suppress high-frequency ***,based on the Na I(Tl)scintillator(u75 mm×75 mm)detector and^(137)Cs source,the effect of the k_(D)value on the energy resolution of the DPZC trapezoidal(triangular)shaping algorithm was *** experimental results show that,with an increase in k_(D),the energy resolution of the system improved and reached the maximum when k_(D)was greater than 10,and the optimal energy resolution of the system was 7.72%.

关键词： Pole-zero cancellation C–R inverse system Trapezoidal/triangular shaping Amplitude–frequency characteristics Energy resolution

Full-frame Data Reduction Method:A Data Mining Tool to Detect the Potential Variations in Optical Photometry

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Research in Astronomy and Astrophysics 2023年第5期23卷 110-141页

作者： Zhi-bin Dai Hao Zhou jin Cao Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China School of Information Science and Engineering of Yunnan University Kunming 650500China

A Synchronous Photometry Data Extraction(SPDE)program,performing indiscriminate monitoring of all stars appearing in the same field of view of an astronomical image,is developed by integrating several Astropy affiliated packages to make full use of time series observed by traditional small/medium aperture ground-based *** complete full-frame stellar photometry data reductions implemented for the two time series of cataclysmic variables:RX J2102.0+3359 and Paloma J0524+4244 produce 363 and 641 optimal light curves,respectively.A cross-identification with SIMBAD finds 23 known stars,of which 16 are red giant-/horizontal-branch stars,2 W UMa-type eclipsing variables,2 program stars,an X-ray source and 2 Asteroid Terrestrial-impact Last Alert System *** on the data products from the SPDE program,a follow-up light curve analysis program identifies 32 potential variable light curves,of which 18 are from the time series of RX J2102.0+3359,and 14 are from that of Paloma J0524+*** are preliminarily separated into periodic,transient,and peculiar *** querying for the 58 VizieR online data catalogs,their physical parameters and multi-band brightness spanning X-ray to radio are compiled for future analysis.

关键词： catalogs-stars fundamental parameters-stars variables general-methods data analysis-techniques photometric