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Design and analysis of Salisbury screens and Jaumann absorbers for solar radiation absorption

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Frontiers in Energy 2018年第1期12卷 158-168页

作者： xing FANG C. Y. ZHAO hua BAO Institute of Engineering Thermophysics Shanghai Jiao Tong UniversityShanghai 200240 China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong University Shanghai 200240 China

Two types of resonance absorbers, i.e., Salis- bury screens and Jaumann absorbers are systematically investigated in solar radiation absorption. Salisbury screen is a metal-dielectric-metal structure which overcomes the drawback of bulky thickness for solar spectrum. Such structures have a good spectral selective absorption property, which is also insensitive to incident angles and polarizations. To further broaden absorption bandwidth, more metal and dielectric films are taken in the structure to form Jaumann absorbers. To design optimized structural parameters, the admittance matching equations have been derived in this paper to give good initial structures, which are valuable for the following optimization. Moreover, the analysis of admittance loci has been conducted to directly show the effect of each layer on the spectral absorptivity, and then the effect of thin films is well understood. Since the fabrication of these layered absorbers is much easier than that of other nanostructured absorbers, Salisbury screen and Jaumann absorbers have a great potential in large-area applications.

关键词： thin films admittance loci solar absorber

Mechanical Properties and Fracture Behavior of Cu-Co-Be Alloy after Plastic Deformation and Heat Treatment

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Journal of Iron and Steel Research International 2016年第9期23卷 933-939页

作者： Yan-jun ZHOU Ke-xing SONG Jian-dong xing Zhou LI Xiu-hua GUO State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong University School of Materials Science and Engineering Henan University of Science and Technology Collaborative Innovation Center of Nonferrous Metals Henan University of Science and Technology School of Materials Science and Engineering Central South University

Mechanical properties and fracture behavior of Cu-0.84Co 0.23Be alloy after plastic deformation and heat treatment were comparatively investigated. Severe plastic deformation by hot extrusion and cold drawing was adopted to induce large plastic strain of Cu 0.84Co-0.23Be alloy. The tensile strength and elongation are up to 476.6 MPa and 18%, respectively. The fractured surface consists of deep dimples and micro voids. Due to the formation of su- persaturated solid solution on the Cu matrix by solution treatment at 950℃ for 1 h, the tensile strength decreased to 271.9 MPa, while the elongation increased to 42%. The fracture morphology is parabolic dimple. Furthermore, the tensile strength increased significantly to 580.2 MPa after aging at 480 ℃ for 4 h. During the aging process, a large number of precipitates formed and distributed on the Cu matrix. The fracture feature of aged specimens with low elongation （4.6%） exhibits an obvious brittle intergranular fracture. It is confirmed that the mechanical properties and fracture behavior are dominated by the microstrueture characteristics of Cu-0.84Co 0.23Be alloy after plastic de- formation and heat treatment. In addition, the fracture behavior at 450 ℃ of aged Cu-0.84Co 0.23Be alloy was also studied. The tensile strength and elongation are 383.6 MPa and 11.2%, respectively. The fractured morphologies are mainly candy-shaped with partial parabolic dimples and equiaxed dimples. The fracture mode is multi mixed mechanism that brittle intergranular fracture plays a dominant role and ductile fracture is secondary.

关键词： Cu-Co-Be alloy heat treatment mechanical property fracture behavior plastic deformation

Combined experimental and simulation study on corrosion behavior of B10 copper-nickel alloy welded joint under local turbulence

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Journal of Iron and Steel Research International 2023年第8期30卷 1598-1612页

作者： Da-lei Zhang Ran Liul Ying-shuang Liul Shao-hua xing Zong-hao He Yao Qian Jin-zeng Liu Xiao-hui Dou Xin-wei Zhang School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266237ShandongChina

The corrosion behavior of B10 copper-nickel alloy welded joints in seawater pipeline system was analyzed under local turbulence induced by weld residual *** corrosion behavior was evaluated by array electrode technology,mor-phology and elemental characterization,and COMSOL Multiphysics *** results provide a theoretical basis for the corrosion and leakage of B10 alloy in seawater pipeline under the action of *** results show that residual height-induced turbulence exhibits a significant effect on the corrosion behavior in different areas of welded joints in B10 *** can damage some surfaces,causing polarity deflection followed by acceleration of corrosion,or it is easier to form a protective film to slow down *** Multiphysics results show that the shear rate and turbulent kinetic energy increase linearly with the increase in residual height and *** corrosion behavior of alloy surface is influenced by controlling the mass transfer rate and surface state.

关键词： Array electrode technology Welded joint Corrosion COMSOL Multiphysics simulation Seawater

Application of a support vector machine for prediction of slope stability

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Science China(Technological Sciences) 2014年第12期57卷 2379-2386页

作者： XUE Xin hua YANG xing Guo CHEN Xin State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University College of Water Resource and Hydropower Sichuan University

Slope stability estimation is an engineering problem that involves several parameters. To address these problems, a hybrid model based on the combination of support vector machine(SVM) and particle swarm optimization(PSO) is proposed in this study to improve the forecasting performance. PSO was employed in selecting the appropriate SVM parameters to enhance the forecasting accuracy. Several important parameters, including the magnitude of unit weight, cohesion, angle of internal friction, slope angle, height, pore water pressure coefficient, were used as the input parameters, while the status of slope was the output parameter. The results show that the PSO-SVM is a powerful computational tool that can be used to predict the slope stability.

关键词： slope stability support vector machine particle swarm optimization prediction

Colon Interposition for Corrosive Esophageal Stricture: Single Institution Experience with 119 Cases

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Current Medical Science 2019年第3期39卷 415-418页

作者： Wen-hui zeng Wan-li JIANG Gan-jun KANG xing-hua ZHANG Guo-hua FAN Qing GENG Song-ping XIE Jie huaNG Department of Thoracic Surgery Renmin Hospital of Wuhan University Wuhan 430060 China

The colon is an alternative graft organ for esophageal *** present study reviewed our experience with the colon interposition for esophageal replacement following corrosive ingestion,to evaluate the outcomes of colon interposition based on our surgical experience. The clinical data of 119 patients who underwent colon interposition for esophageal replacement from January 2005 to March 2017 were retrospectively analyzed. The routes of the colon interposition were retrosternal in 119 (100%). The median operative time was 390 min (range: 290-610 min) and the median blood loss was 615 mL (range:270-2500 mL). Of these 119 patients, the cervical anastomosis was performed at the hypopharynx (n=20,16.8%), the larynx (n=3,2.5%), and the cervical esophagus (n=96, 80.7%). Five patients experienced cervical anastomotic leakage (4 cases for esophagus-colon, and one for hypopharynx-colon).One patient experienced wound infection of the abdominal wall. Three patients had injury of recurrent laryngeal nerve and hoarseness. Three patients had stress ulcer with bleeding and treated with octreotide. Two patients suffered from incomplete intestinal obstruction. The postoperative follow-up was made for 12 months in all patients and all of them were alive. In conclusion, The colon is well-suited for esophageal reconstruction. The selection of the colon graft should be flexible and be based on the inspection of blood supply and the length needed. We must therefore make every effort to reduce the number of postoperative complications, and improve the quality of life for patients.

关键词： corrosive esophageal stricture colon interposition outcomes

Structure of Independent Sets in Direct Products of Some Vertex-transitive Graphs

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Acta Mathematica Sinica,English Series 2012年第4期28卷 697-706页

作者： xing Bo GENG Jun WANG hua Jun ZHANG School of Mathematical Science Dalian University of Technology Department of Mathematics Shanghai Normal University Department of Mathematics Zhejiang Normal University

Let Circ（r, n） be a circular graph. It is well known that its independence number α（Circ（r, n）） = r. In this paper we prove that for every vertex transitive graph H, and describe the structure of maximum independent sets in Circ（r, n） × H. As consequences, we prove for G being Kneser graphs, and the graphs defined by permutations and partial permutations, respectively. The structure of maximum independent sets in these direct products is also described.

关键词： Vertex-transitivity primitivity independence number

New explicit algebraic stress and flux model for active scalar and simulation of shear stratified cylinder wake flow

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Science China(Technological Sciences) 2009年第9期52卷 2536-2546页

作者： hua ZuLin GU Li xing LingHang DAI WenHong Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education College of Environmental Science&EngineeringHohai UniversityNanjing 210098China Yangtze River Scientific Research Institute Wuhan 430010China Centre for Water and Environment Queen’s UniversityKingstonOntarioK7L3N6Canada

On the numerical simulation of active scalar,a new explicit algebraic expression on active scalar flux was derived based on Wikstrm,Wallin and Johansson model (aWWJ model). Reynolds stress algebraic expressions were added by a term to account for the buoyancy effect. The new explicit Reynolds stress and active scalar flux model was then established. Governing equations of this model were solved by finite volume method with unstructured grids. The thermal shear stratified cylinder wake flow was computed by this new model. The computational results are in good agreement with laboratorial measurements. This work is the development on modeling of explicit algebraic Reynolds stress and scalar flux,and is also a further modification of the aWWJ model for complex situations such as a shear stratified flow.

关键词： active scalar explicit algebraic model scalar flux Reynolds stress thermal shear stratified cylinder wake flow numerical simulation

Role of Nitric Oxide Dependence on Nitric Oxide Synthase-like Activity in the Water Stress Signaling of Maize Seedling

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Journal of Integrative Plant Biology 2008年第4期50卷 435-442页

作者： Gang-Ping Hao Yu xing Jian-hua Zhang Department of Biological Science Taishan Medical University Taian 271000 China Department of Biology Hong Kong Baptist University Hong Kong China

Nitric oxide （NO） has been known as an important signal in plant antioxidative defense but its production and roles in water stress are less known. The present study investigated whether NO dependence on a NO synthase-like （NOS） activity is involved in the signaling of drought-induced protective responses in maize seedlings. NOS activity, rate of NO release and drought responses were analyzed when NO donor sodium nitroprusside （SNP）, NO scavenger c-PTIO （2-（4-carboxyphenyl）- 4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide） and NOS inhibitor L-NAME （NG-nitro-L-arginine methyl ester） were applied to both detached maize leaves and whole plants. Both NOS activity and the rate of NO release increased substantially under dehydration stress. The high NOS activity induced by c-PTIO as NO scavenger and NO accumulation inhibited by NOS inhibitor L-NAME in dehydration-treated maize seedlings indicated that most NO production under water deficit stress may be generated from NOS-like activity. After dehydration stress for 3 h, detached maize leaves pretreated with NO donor SNP maintained more water content than that of control leaves pretreated with water. This result was consistent with the decrease in the transpiration rate of SNP-treated leaves subjected to drought treatment for 3 h. Membrane permeability, a cell injury index, was lower in SNP-treated maize leaves under dehydration stress for 4 h when compared with the control leaves. Also, superoxide dismutase （SOD） activity of SNP combined drought treatment maize leaves was higher than that of drought treatment alone, indicating that exogenous NO treatment alleviated the water loss and oxidative damage of maize leaves under water deficit stress. When c-PTIO as a specific NO scavenger was applied, the effects of applied SNP were overridden. Treatment with L-NAME on leaves also led to higher membrane permeability, higher transpiration rate and lower SOD activities than those of control leaves, indicating that NOS-like activity

关键词： anti-oxidative defense maize (Zea mays) nitric oxide nitric oxide synthase signal transduction water stress.

Explicit Representations for Local Lagrangian Numerical Differentiation

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Acta Mathematica Sinica,English Series 2007年第2期23卷 365-372页

作者： He Yu WANG Feng CUI xing hua WANG Computing Center Zhejiang University Department of Mathematics Hong Kong Baptist University Department of Mathematics Zhejiang University

It is shown that in Lagrangian numerical differentiation formulas, the coefficients are explicitly expressed by means of cycle indicator polynomials of symmetric group. Moreover, asymptotic expansions of the remainders are also explicitly represented as a fixed number of interpolation nodes approaching infinitely to the point at which the derivative is evaluated. This implies that complete explicit formulas for local Lagrangian numerical differentiation can be obtained.

关键词： numerical differentiation explicit representation local estimate symmetric group cycle indicator