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Simulation of Ultrasonic Propagation Based on Raying　Model in Typical Structure

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Journal of Materials Science & Technology 2003年第z1期19卷 125-128页

作者： tie GANG Weizhi zhang Liwei GUO State Key Lab. of AWPT Harbin Institute of Technology Harbin 150001 China State Key Lab. of AWPT Harbin Institute of Technology Harbin 150001 China State Key Lab. of AWPT Harbin Institute of Technology Harbin 150001 China

The convenient and useful raying mode was selected to develop the analysis module of ultrasonic parameters, and the simulation of ultrasonic propagation in typical plane structure was carried out. Using this model, the ultrasonic propagation in the water immersion testing was analyzed. For the complex plate structure, the intelligent analysis and simulation module was developed.

关键词： Ultrasonic testing, Ray modeling, Computer simulation

Electrodeposition of photocatalytic TiO2 film on surface of alumina prepared by anodic oxidation

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中国有色金属学会会刊：英文版 2004年第z1期14卷 173-177页

作者： zhang Xin-yu CHEN tie-qun College of Mechanical Engineering South China University of TechnologyGuangzhou 510640 China College of Mechanical Engineering South China University of TechnologyGuangzhou 510640 China

A new electrochemical method to prepare photocatalytic TiO2 thin film was developed, by which the TiO2 was electrodeposited on surface of alumina by AC electrolysis in solution consisting of K2 [TiO(C2O4 )2] and C2H2O4. The deposited TiO2 thin film was primarily characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM) and energy dispersive spectrum (EDS) methods. The photocatalytic properties of this film were also studied by the photocatalytic degradation of methyl orange. The results show that the TiO2 film electrodeposited by this method is mainly in amorphous and with a little crystalline component mixed anatase and rutile. The surface of the alumina prepared by anodic oxidation is porous and the TiO2 electrodeposited on it is scattered and incompact. TiO2 thin film fixed on the surface of alumina shows photocatalytic activity to the degradation of methyl orange.

关键词： electrodeposition TiO2 film alumina anodic oxidation

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Chord error constraint based integrated control strategy for contour error compensation

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Frontiers of Mechanical Engineering 2020年第4期15卷 645-658页

作者： tie zhang Caicheng WU Yanbiao ZOU School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China

As the traditional cross-coupling control method cannot meet the requirements for tracking accuracy and contour control accuracy in large curvature positions, an integrated control strategy of cross-coupling contour error compensation based on chord error constraint, which consists of a cross-coupling controller and an improved position error compensator, is proposed. To reduce the contour error, a PI-type cross-coupling controller is designed, with its stability being analyzed by using the contour error transfer function. Moreover, a feed rate regulator based on the chord error constraint is proposed, which performs speed planning with the maximum feed rate allowed by the large curvature position as the constraint condition, so as to meet the requirements of large curvature positions for the chord error. Besides, an improved position error compensation method is further presented by combining the feed rate regulator with the position error compensator, which improves the tracking accuracy via the advance compensation of tracking error. The biaxial experimental results of non-uniform rational B-splines curves indicate that the proposed integrated control strategy can significantly improve the tracking and contour control accuracy in biaxial contour following tasks.

关键词： cross-coupling controller contour error tracking error position error compensator feed rate regulator

Microstructure,mechanical and thermal properties of Ni-P(-SiC)coating on high volume fraction SiC_(p)/Al composite

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Rare Metals 2023年第2期42卷 705-712页

作者： Gui-Wu Liu Wen-Qiang Luo Xiang-Zhao zhang Hai-cheng Shao tie-Zheng Pan Guan-Jun Qiao School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China Suzhou Pant Piezoelectric Tech Co.Ltd. Suzhou215300China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

Ni-P(-SiC)composite coatings were successfully deposited on 70 vol%SiC_(p)/Al composite by electroless *** surface microstructures and the phase structures of the Ni-P(-SiC)coatings were examined and analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD)before and after heat-treatment at200-400℃for 2 *** thermal diffusivity of the deposited samples and the interface adhesion between the coating and the substrate were *** experimental results show that SiC content in the coatings increases obviously and XRD peaks are enhanced with SiC content in the bath increasing from 3 to 9 g·L^(-1).After heat-treatment,the surface of the coating becomes smoother and no diffusion layer is produced at the interface.A new phase Ni3P forms in the coating during heat-treatment at 400℃.The critical load(L_(c))of Ni-P-SiC composite coating on SiC_(p)/Al composite reaches the maximum value of 84.9 N with SiC content of 3 g·L^(-1)after heat-treatment at 200℃and more or less decreases with the increase in SiC content and heat-treatment *** thermal diffusivity of deposited samples gradually increases as the temperature increases;however,it reduces firstly and then climbs with the increase in SiC content.

关键词： Ni-P-SiC coating SiC_(p)/Al composite Microstructure Adhesion force Thermal diffusivity

ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期 272-283页

作者： Yuwei Hua Yizhi zhang Zhenming Guo Shan Bian Yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

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Accuracy Enhancement of Discontinuous Galerkin Method for Hyperbolic Systems

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Numerical Mathematics(Theory,Methods and Applications) 2014年第2期7卷 214-233页

作者： tie zhang Jingna Liu Department of Mathematics and the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110004China

We study the enhancement of accuracy,by means of the convolution postprocessing technique,for discontinuous Galerkin(DG)approximations to hyperbolic *** investigations have focused on the superconvergence obtained by this technique for elliptic,time-dependent hyperbolic and convection-diffusion *** this paper,we demonstrate that it is possible to extend this postprocessing technique to the hyperbolic problems written as the Friedrichs’systems by using an upwind-like DG *** prove that the L2-error of the DG solution is of order k+1/2,and further the post-processed DG solution is of order 2k+1 if Qkpolynomials are *** key element of our analysis is to derive the(2k+1)-order negative norm error *** experiments are provided to illustrate the theoretical analysis.

关键词： Discontinuous Galerkin method hyperbolic problem accuracy enhancement postprocessing negative norm error estimate

Ecosystem valuation and the conservation of wild lands in vigorous economic regions:A case study in Jiuduansha Wetland,Shanghai

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Chinese Science Bulletin 2007年第19期52卷 2664-2674页

作者： SU tie zhang EnDi School of Life Sciences East China Normal University Shanghai 200062 China

As the loss of wild lands to satisfy traditional economic development has become a global environmental problem in recent decades, using ecosystem valuation to estimate the total economic value (TEV) of an ecosystem has become popular. The main purpose of the ecosystem valuation is to strengthen the importance of ecosystems, and bring the ecosystem services into the traditional cost-benefit analyses of land use strategy. Some studies have illustrated that in remote areas, wilderness can produce more value if it is conserved, rather than converted to traditional agricultural or industrial uses. The same situation does not seem to exist in vigorous economic regions. Thus, a case study was conducted on the Jiuduansha Wetland in Shanghai using three approaches: the direct market valuation, the replacement valuation and the contingent valuation. The net present TEVs of three land use scenarios over one hundred years were evaluated. The results proved that simply based on ecosystem valuation, when compared with the other two scenarios of "conservation" and "selective use", "partial conversion into terrene (dry land)" of Jiuduansha might be the optimal scenario for the well-being of the people in Shanghai. Land price was identified as the most important factor. This situation is likely due to the scarcity of land available for traditional economic development in Shanghai. Thus, we speculated that the fate of the wilderness to "be destroyed" in vigorous economic regions could not be changed simply based on ecosystem valuation. However, the variety of interest by local residents in wilderness might enhance the TEVs of scenarios such as "conservation" and "selective use", and affect the valuation results. Since some important benefits of natural ecosystems remain unknown and others are underestimated, we suggested that any land use decisions regarding the Jiuduansha Wetland should be conservative and cautious as converting wetlands into terrene is an irreversible process.

关键词：土地利用生态评价湿地环境

Targeting Epac2 and GluA3-containing AMPARs:a novel therapeutic strategy for Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3223-3224页

作者： Tong zhang Martina Schmidt Department of Molecular Pharmacology Groningen Research Institute of PharmacyUniversity of GroningenGroningenThe Netherlands School of Pharmacy Tianjin Medical UniversityTianjinChina

Alzheimer's disease(AD)is a neurodegenerative disease that manifests progressive decline in memory and *** the early stage of AD,memory retrieval is impaired preceding memory acquisition and consolidation(Roy et al.,2016).Prior to the onset of symptoms,pathological amyloid-β(Aβ)plagues and tau protein tangles accumulate in extracellular and intracellular spaces,respectively,leading to *** these hallmark pathologies,Aβ is proposed to be the primary etiology by triggering a cascade of pathogenic events,including neuroinflammation,oxidative stress,tau hyperphosphorylation,synaptic/neuronal dysfunction,and neuronal death(zhang et al.,2023b).

关键词： Alzheimer impaired Aβ