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Journal of Iron and Steel Research International 2023年第1期30卷 150-157页

作者： xu Xie Ming zhong Tan Zhao Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China State Key Laboratory of Metal Material for Marine Equipment and Application Ansteel Co.Ltd.Anshan 114021LiaoningChina

Fused CaF_(2)-TiO_(2) fluxes have been designed,prepared,and applied in the flux cored wires to join EH36 shipbuilding steels under high heat input electro-gas *** microstructural evolution in the weld metals subjected to varied CaF_(2)-TiO_(2) flux cored wires has been fully *** has been demonstrated that as the content of TiO2 in the fused fluxes increases,columnar grain size increases,and major constituents in the weld metal change from lath bainite,to granular bainite,and then to acicular *** phenomena are elucidated via salient chemical reactions involving oxygen pickup and concurrent titanium transfer.

关键词： Microstructural evolution Elemental variation Electro-gas welding High heat input Shipbuilding steel

An Exact Generalized Test for Homogeneity of Inverse Gaussian Scale Parameters

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 761-769页

作者： xu-hua LIU Xing-zhong xu Wei-yan MU Department of Mathematics China Agricultural University Beijing 100083 China College of Mathematics Beijing Institute of Technology Beijing 100081 China School of Science Beijing University of Civil Engineering and Architecture Beijing 100044 China

In this paper, we propose a new generalized p-value for testing homogeneity of scale parameters λi from k independent inverse Gaussian populations. The proposed generalized p-value is proved to have exact frequentist property, and it is also invariant under the group of scale transformation. Simulation results indicate that the proposed test is better than existing approximate χ^2 test.

关键词： Inverse Gaussian distribution Generalized p-value Exact frequentist property

Estimation of velocity potential of water waves using a Luenberger-like observer

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Science China(Information Sciences) 2020年第12期63卷 139-152页

作者： Yang YU Hai-Long PEI Cheng-zhong xu Key Laboratory of Autonomous Systems and Networked Control Ministry of EducationSouth China University of Technology Unmanned Aerial Vehicle Systems Engineering Technology Research Center of Guangzhou South China University of Technology LAGEPP University Claude Bernard-Lyon 1

We propose a Luenberger-like observer for a water wave system. The water wave dynamics are assumed to be governed by the linearized water wave equation(LWWE). Our proposed observer estimates the velocity potential of water waves by measuring only the surface wave elevation. The information of the water-wave velocity field is then extracted from the gradient of the velocity potential. It is shown that the estimation error of the observer converges exponentially to zero as time tends to infinity. Furthermore,we numerically solve the LWWE and observer equation by the finite difference method. The efficiency of our proposed numerical scheme and the performance of the observer are validated by numerical simulation results.

关键词： linearized water wave equation LWWE Luenberger-like observer numerical simulations

Glow Discharge Plasma-Assisted Preparation of Nickel-Based Catalyst for Carbon Dioxide Reforming of Methane

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Chinese Journal of Chemical Physics 2008年第5期21卷 481-486页

作者： Fang Guo Wei Chu Jun-qiang xu Lin zhong Department of Chemical Engineering Sichuan University Chengdu 610065 China Department of Chemical and Biological Engineering Chongqing Institute of Technology Chongqing 400050 China

A plasma-assisted method was employed to prepare Ni/γ-All2O3 catalyst for carbon dioxide reforming of methane reaction. The novel catalyst possessed higher activity and better coke-suppression performance than those of the conventional calcination catalyst. To achieve the same CH4 conversion, the conventional catalyst needed higher reaction temperature, about 50 ℃ higher than that of the N2 plasma-treated catalyst. After the evaluation test, the deactivation rate of the novel catalyst was 1.7%, compared with 15.2% for the conventional catalyst. Different from the characterization results of the calcined catalyst, a smaller average pore diameter and a higher specific surface area were obtained for the plasma-treated catalyst. The variations of the reduction peak temperatures and areas indicated that the catalyst reducibility was promoted by plasma assistance. The dispersion of nickel was also remarkably improved, which was helpful for controlling the ensemble size of metal atoms on the catalyst surface. The modification effect of plasma- assisted preparation on the surface property of alumina supported catalyst was speculated to account for the concentration increase of absorbed CO2. An enhancement of CO2 adsorption was propitious to the inhibition of carbon formation. The coke amount deposited on plasma treated catalyst was much smaller than that on the conventional catalyst.

关键词： Nickel-based catalyst Plasma CO2 reforming of CH4 Coke Adsorption of CO2

Operation optimization of the steel manufacturing process: A brief review

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1274-1287页

作者： Zhao-jun xu zhong Zheng Xiao-qiang Gao College of Material Science and Engineering Chongqing UniversityChongqing 400045China School of Economics and Business Administration Chongqing UniversityChongqing 400030China

Against the realistic background of excess production capacity, product structure imbalance, and high material and energy consumption in steel enterprises, the implementation of operation optimization for the steel manufacturing process is essential to reduce the production cost, increase the production or energy efficiency, and improve production management. In this study, the operation optimization problem of the steel manufacturing process, which needed to go through a complex production organization from customers' orders to workshop production, was analyzed. The existing research on the operation optimization techniques, including process simulation, production planning, production scheduling, interface scheduling, and scheduling of auxiliary equipment, was reviewed. The literature review reveals that, although considerable research has been conducted to optimize the operation of steel production, these techniques are usually independent and ***, the future work related to operation optimization of the steel manufacturing process based on the integration of multi technologies and the intersection of multi disciplines were summarized.

关键词： intelligent manufacturing operation optimization steel manufacturing process process simulation production planning production scheduling

Multiplicative Integral Theory of Generalized Orthopair Fuzzy Sets and Its Applications

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Journal of Systems Science and Systems Engineering 2022年第4期31卷 457-479页

作者： Jie Gao Zeshui xu Chao zhong Yunshu Mao School of Business Administration Southwestern University of Finance and EconomicsChengdu610207China Business School Sichuan UniversityChengdu610064China

There are two main issues of fuzzy multi-attribute decision-making:determine the weight of each attribute and choose an appropriate aggregation method to integrate the evaluation information of different *** order to solve the multi-attribute decision-making problem in generalized orthopair fuzzy environment with unknown attribute weights more effectively,we give a decision-making method based on generalized orthopair fuzzy definite *** be specific,we first introduce the complement operations of q-rung orthopair fuzzy numbers,and then investigate the multiplicative q-rung orthopair fuzzy *** the complement operations,we establish the mutual conversion formula between additive and multiplicative q-rung orthopair fuzzy calculus ***,we give a multiplicative integral-based q-rung orthopair fuzzy multi-attribute decision-making method,and discuss the relationship between the q-rung orthopair fuzzy definite integrals and the q-rung orthopair fuzzy weighted geometric *** with traditional decision-making methods,this method does not rely on subjective weight information,which is especially important when dealing with large sample ***,the application of election is studied to verify the feasibility and effectiveness of the proposed *** the introduction of generalized orthopair fuzzy sets,the expression form of election evaluation information has been *** also provide some examples to compare the obtained results with the results generated by the addition operation and reveal the correlation between them.

关键词： Fuzzy sets decision making aggregation operators

Preparation and near-infrared optical limiting property of fluorene-containing functional polyacetylene

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Chinese Chemical Letters 2011年第10期22卷 1257-1260页

作者： nai Bo Lin Yan Feng Shan Yi Guang Hong Yao xu College of Material Science and Engineering ＆ College of Chemistry and Chemical Engineering Donghua University Shanghai 201620 China College of Chemistry and Chemical Engineering Anhui University Hefei 230039 China

A novel functional polyacetylene containing fluorene group as a pendant,poly（2-（p-methylstyrene）-7-acetylene-9,9-dioctyl-fluorene）, was synthesized in moderate yield by[Rh（nbd）Cl]_2-Et_3N *** structures and properties of monomer and polymer were characterized and evaluated with FTIR,NMR,UV-vis,GPC and Z-scan,*** results show that the incorporation of fluorene into polyacetylene has endowed the resultant polymer with well optical limiting properties for laser at wavelength 780 nm based on two-photon absorption mechanism.

关键词： Substituted polyacetylene Fluorene Nonlinear optics Two-photon absorption

Liquid phase in-situ synthesis of LiF coated boron powder composite and performance study

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Defence Technology（防务技术） 2020年第3期16卷 635-641页

作者： Yang xu Qing-zhong Cui Cheng-wen Zhao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Shanxi Jiangyang Chemical Factory Shanxi 030000China

Among practical metal additives,boron(B) has a high volumetric heating value,making it a promising choice as a fuel *** B can theoretically yield a large amount of energy upon complete combustion,its combustion is retarded by the initial presence of B oxide,which coats the surfaces of B *** improve the ignition and combustion properties of B powder,LiOH and NH4F were used as precursors to synthesize uniformly LiF-coated B composites(LiF-B) in *** LiF-B mixture was also prepared for comparison using a physical method.X-ray diffraction(XRD),Fourier-transform infrared(FTIR),scanning electron microscope(SEM),and energy-dispersive X-ray spectroscopy(EDS) were used to characterize the morphologies and compositions of the *** thermal and combustion properties of the samples were characterized by thermal gravity-differential thermal gravity(TG-DTG),differential scanning calo rimetry(DSC) and closed bomb *** XRD,FTIR,SEM and EDS results demonstrated the successful preparation of the coated LiF-B *** TG-DTG and closed bomb experiment results indicated that the addition of LiF decreased the ignition temperature of B powder,and increasing its reaction *** results show that when LiF-B was added,the released heat of underwater explosive increased by 6727.2,7280.4 and 3109.6 J/g at heating rates of 5,10,and 15℃/min,***,LiF-B decreased the activation energy of secondary combustion reaction of explosive system as calculated through Kissinger’s method by 28.9%,which indicated an excellent catalytic effect for the thermal decomposition of underwater *** results reveal that LiF can improve the combustion efficiency of B powder,thereby increasing the total energy of *** mechanical sensitivity increased slightly after adding LiF-B to the underwater *** mpared to the underwater explosive with added B,the mechanical sensitivity of the explosive with added LiF-B was significantly

关键词： Boron LiF Coating Thermal decomposition properties Energy efficiency

Cooper Pairing Near the Boundary in the -U Hubbard Model

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Chinese Physics Letters 1997年第9期14卷 698-700页

作者： xu Yuan YAN Xin-zhong Institute of Physics Chinese Academy of SciencesBeijing 100080

The Cooper pairing near the boundary of a superconductor is analyzed by using the linear-response theory The system is described by the square lattice(t,-U)Hubbard model occupying half *** half filling,the pairing also corresponds to the antiferromagnetic ordering in the repulsive Hubbard *** numerical result clearly shows that,at weak to intermediate coupling(U/t≤l),the boundary exerts strong influence on the order parameter;the weaker the coupling,the deeper the order parameter is suppressed near the *** present scheme is valid in the whole temperature regime of Cooper pairing.

关键词： space. Hubbard coupling

Research progress based on observations of the New Vacuum Solar Telescope

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Science China(Technological Sciences) 2020年第9期63卷 1656-1674页

作者： YAN XiaoLi LIU zhong ZHANG Jun xu Zhi Yunnan Observatories Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The purpose of this paper is to introduce the main scientific results made by the one-meter New Vacuum Solar Telescope(NVST),which was put into commission on 2010. NVST is one of the large aperture solar telescopes in the world, located on the shore of Fuxian lake of Yunnan province in China, aiming at serving solar physicists by providing them with high resolution photospheric and chromospheric observational data. Based on the data from NVST and complementary observations from space(e.g.,Hinode, SDO and IRIS, etc), dozens of scientific papers have been published with a wide range of topics concentrating mainly on dynamics and activities of fine-scale magnetic structures and their roles in the eruptions of active-region filaments and *** achievements include dynamic characteristics of photospheric bright points, umbral dots, penumbral waves, and sunspot/light bridge oscillation, observational evidence of small-scale magnetic reconnection, and fine-scale dynamic structure of *** these new results will shed light on the better understanding of solar eruptive activities. Data release, observation proposals,and future research subjects are introduced and discussed.

关键词： sunspots solar flares solar filaments/prominences jets Ellerman bombs magnetic reconnection