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Seismic hazard prediction using multispectral amplification maps in a complex topographic area: A case study of Qiaozhuang town, Sichuan Province, Southwest China

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Journal of Mountain Science 2022年第3期19卷 726-739页

作者： LUO Yong-hong XU Qiang zhan wei-wei GRELLE Gerardo State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection Chengdu University of TechnologyChengdu 610059China Department of Civil and Environmental Engineering Tufts UniversityMedfordMA 02155USA Department of Civil and Environment Engineering University of RomeRome 00184Italy

Earthquakes can cause widely distributed slope failures and damage in mountainous *** accurate prediction of ground motions in mountainous areas is essential for managing the seismic risk of urban cities near mountains but is restricted primarily by complex seismic site amplification effects in areas of uneven *** study selected Qiaozhuang town located in the Qingchuan–Pingwu fault zone,Southwest China,as a case study.A simulator for mapped seismic responses using a hybrid model(Si Se RHMap)was applied to compute the multispectral seismic topographic amplification maps at the three slope units surrounding Qiaozhuang town(weigan hill,***,and ***).Post-earthquake damage survey maps,1 D seismic site response spectral ratios,and H/V spectral ratios of earthquake data were used to validate the computed seismic site amplification factors and resonance *** results suggest that strong topographic amplification effects usually occur at distinct slope locations,such as hilltops,convex slope positions,upslope,and narrow *** computed topographic amplification factors in the study area reached up to 2.4 at upslope or hilltops,and the resonance frequencies were between 3 and 10 *** effects can be as important as stratigraphic effects when assessing seismic amplification effects in the study *** conclude that both topographic and stratigraphic effects should be considered in the comprehensive seismic hazard assessment of the study area or other similar mountain towns.

关键词： Seismic hazard prediction Multispectral amplification map topographic effects Stratigraphic effects SiSeRHMap Wenchuan earthquake

Biologically inspired collective construction with visual landmarks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第5期13卷 315-327页

作者： Zheng-wei zhan Hong zhanG Yi-bin LI School of Control Science and Engineering Shandong University Jinan 250061 China Department of Computing Science University of Alberta Edmonton Alberta T6G 2E8 Canada

We describe our research in using environmental visual landmarks as the basis for completing simple robot construction *** by honeybee visual navigation behavior,a visual template mechanism is proposed in which a natural landmark serves as a visual reference or template for distance determination as well as for navigation during collective *** validate our proposed mechanism,a wall construction problem is investigated and a minimalist solution is *** results show that,using the mechanism of a visual template,a collective robotic system can successfully build the desired structure in a decentralized fashion using only local sensing and no direct *** addition,a particular variable,which defines tolerance for alignment of the structure,is found to impact the system *** decreasing the value of the variable,system performance is improved at the expense of a longer construction *** visual template mechanism is appealing in that it can use a reference point or salient object in a natural environment that is new or unexplored and it could be adapted to facilitate more complicated building tasks.

关键词： Biologically inspired Swarm robotics Collective construction Visual landmark Template

Experimental study on ceramic balls impact composite armor

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Defence Technology（防务技术） 2020年第2期16卷 408-416页

作者： wei-zhan Wang Zhi-gang Chen Shun-shan Feng Tai-yong Zhao Underground Target Damage Technology National Defense Key Discipline Laboratory North University of ChinaTaiyuan 030051ShanxiChina State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology100081BeijingChina

Ceramic balls represent a new type of damaging element,and studies on their damaging power of composite armor are required for a comprehensive evaluation of the effectiveness of various types of *** goal of this study was to determine the impact ofφ7 mm toughened Al2 O3 ceramic balls on a composite ceramic/metal *** influences of the ceramic panel and the thickness of the metal backing material on the destroying power of the ceramic balls were first *** on the agreement between numerical simulation,experimental results,and calculation models of the target plate resistance,the response mechanism of the ceramic balls was further *** results indicate that for a back plate of Q235 steel,with an increasing thickness of the ceramic panel,the piercing speed limit of the ceramic balls gradually increases and the diameter of the out-going hole on the metal back *** conditions were tested to assess the effects on the piercing speed,the diameter of the out-going hole,the micro-element stress,and the integrity of the recovered ceramic bowl.

关键词： Impact Penetration Infinitesimal Interface collapse

Photocatalytic activity of ferric oxide/titanium dioxide nanocomposite films on stainless steel fabricated by anodization and ion implantation

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 725-732页

作者： wei-ting zhan Hong-wei Ni Rong-sheng Chen Gao Yue Jun-kai Tai Zi-yang Wang Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology

A simple surface treatment was used to develop photocatalytic activity for stainless steel. AISI 304 stainless steel specimens after anodization were implanted by Ti ions at an extracting voltage of 50 kV with an implantation dose of 3 × 10^15 ***-2 and then annealed in air at 450℃ for 2 h. The morphology was observed by scanning electron microscopy. The microstructure was characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The photocatalytic degradation of methylene blue solution was carried out under ultraviolet light. The corrosion resistance of the stainless steel was evaluated in NaCl solution （3.5 wt%） by electrochemical polarization curves. It is found that the Ti ions depth profile resembles a Gaussian distribution in the implanted layer. The nanostructured Fe203/TiO2 composite film exhibits a remarkable enhancement in photocatalytic activity referenced to the mechanically polished specimen and anodized specimen. Meanwhile, the annealed Ti-implanted specimen remains good corrosion resistance.

关键词： surface treatment stainless steel nanocomposite films photocatalysis ion implantation electrochemicalanodization

Research on Effect of Four Natural Ultraviolet Light Absorbers on Photostabilization of Azadirachtin-A

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Agricultural Sciences in China 2006年第11期5卷 855-858页

作者： TAN wei-hong SONG zhan-qian Institute of Chemical Industry of Forest Products/Key Laboratory on Forest Chemical Engineering Chinese Academy of Forestry Nanjing 210042 P.R.China

This study examined the photostabilization of Azadirachtin-A （Aza-A） when exposed to ultraviolet light in the presence of some natural absorbers. Aza-A extract solutions with and without natural UV light absorbers in methanol were applied onto the surface of glass slides. At particular intervals, the remaining concentration of Aza-A was analyzed by HPLC. Using first-order kinetic equation, the dissipation half-life values （DT^0） for the degradation of Aza-A under ultraviolet radiation were obtained. It indicated that the addition of ferulic acid, gallic acid, and rutin provided moderate degree of photostabilization of Aza-A and that addition of aloin provided the best photostabilization of Aza-A, among these UV absorbers studied. Photostabilization of Aza-A by different UV light absorbers appears to be due to the competitive energy absorption of UV photons by the absorbers molecules. The dissipation half-life values of Aza-A after irradiation under ultraviolet light suggested that the addition of aloin （in 1 ： 1 mol ratio） can provide better photostabilization of azadirachtin molecule.

关键词： ultraviolet light photostabilization Aza-A bioinsecticide

In-line response of vertical cylinders in regular and random waves

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Acta Oceanologica Sinica 2007年第6期26卷 124-138页

作者： LI Yok-sheung SU wei zhan Jiemin zhan Sheng Department of Civil ＆ Structural Engineering The Hong Kong Polytechnic UniversityHong Kong China Department of Applied Mechanics and Engineering Zhongshan University Guangzhou 510275 China

The in-line response of a vertical flexibly mounted cylinder in regular and random waves is reported. Both theoretical analyses and experimental measurements have been performed. The theoretical predictions are based on the Morison equation which is solved by the incremental harmonic balance method. Experiments are then performed in a wave flume to determine the accuracy of the Morison equation in predicting the in-line response of the cylinder in regular and random waves. The interaction between waves and vibrating cylinders are investigated.

关键词： in-line response cylinder waves IHB method

Characterization of ghrelin mRNA expression in fasting Larimichthys crocea juveniles

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Acta Oceanologica Sinica 2021年第6期40卷 35-40页

作者： Feng Liu Xiaokang Lv Tianqi Chu Mengjie Wang wei zhan Bao Lou Institute of Hydrobiology Zhejiang Academy of Agricultural SciencesHangzhou 310021China Key Laboratory of Mariculture and Enhancement of Zhejiang Province Marine Fisheries Research Institute of ZhejiangZhoushan 316021China School of Fishery Zhejiang Ocean UniversityZhoushan 316022China

Larimichthys crocea is a marine fish species cultured in ***-term starvation is often applied to improve the quality of cultured ***,and the expression of ghrelin in tissues of stomach,muscle,brain,intestines,liver,and kidney,involved in starvation response,under starvation conditions were studied to understand the effect of starvation on the expression of ghrelin in *** *** ghrelin expression was tissue-specific,and expression was significantly higher in the stomach compared to other tissues(P<0.01).Additionally,ghrelin expression in different tissues changed along with prolongation of *** the stomach,ghrelin expression levels increased gradually at the beginning of the fast,and then declined after eight days of *** expression in the brain and intestines increased at the beginning of the fast,and then decreased with longer fasting ***,ghrelin expression declined at the beginning of the fast,then increased with longer fasting in the kidneys and *** results suggest that ghrelin is involved in starvation response in *** *** study provids insights into ghrelin function and an important reference for the development of reasonable feeding strategies for *** juveniles.

关键词： Larimichthys crocea starvation ghrelin gene expression

Heat treatment bimetallic PdAu nanocatalyst for oxygen reduction reaction

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Journal of Energy Chemistry 2020年第1期29卷 217-223,I0008页

作者： Qingyun Hu wei zhan Yifei Guo Laiming Luo Ronghua zhang Di Chen Xinwen Zhou College of Biological and Pharmaceutical Science China Three Gorges University

Pd-based nanocatalyst is a potential oxygen reduction oxidation(ORR)catalyst because of its high activity in alkaline medium and low *** this work,bimetallic Pd Au nanocatalysts are prepared by one-pot hydrothermal method using triblock pluronic copolymers,poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)(PEO19-PPO69-PEO19)(P123)as reducer and stabilizer,and heat-treatment method is applied to regulate catalyst structure and improve catalyst *** results show that the heat treatment can agglomerate the catalyst to a certain extent,but effectively improve the crystallinity and alloying degree of the *** ORR performance of the Pd Au nanocatalysts obtained under different heat treatment conditions is systematically *** with commercial Pd black and Pd Au catalyst before heat treatment,the ORR performance of Au Pd nanocatalyst obtained after heat treatment for one hour at 500℃ has been *** Pd Au nanocatalysts after heat treatment also display enhanced anti-methanol toxicity ability in acidic medium.

关键词： PdAu catalysts Nanochain Heat treatment Oxygen reduction reaction Anti-methanol oxidation

Antibacterial properties and corrosion resistance of AISI 420 stainless steels implanted by silver and copper ions

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 322-327页

作者： Hong-wei Ni Han-shuang zhang Rong-sheng Chen wei-ting zhan Kai-fu Huo Zhen-yu Zuo Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education School of Materials and Metallurgy Wuhan University of Science andTechnology Wuhan 430081 China

Silver or copper ions are often chosen as antibacterial agents. But a few reports are concerned with these two antibacterial agents for preparation of antibacterial stainless steel （SS）. The antibacterial properties and corrosion resistance of AISI 420 stainless steel implanted by silver and copper ions were investigated. Due to the cooperative antibacterial effect of silver and copper ions, the Ag/Cu implanted SS showed excellent antibacterial activities against both Gram-negative Escherichia coli （E. coli） and Gram-positive Staphylococcus aureus （S. aureus） at a total implantation dose of 2~ 1017 ions/cm2. Electrochemical polarization curves revealed that the corrosion resistance of Ag/Cu implanted SS was slightly enhanced as compared with that of un-implanted SS, The implanted layer was characterized by X-ray photoelec- tron spectroscopy （XPS）. Core level XPS spectra indicate that the implanted silver and copper ions exist in metallic state in the implanted layer.

关键词： ion implantation antibacterial properties stainless steel Escherichia coli Staphylococcus aureus corrosion resistance