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Chinese Journal of Polymer Science 2020年第2期38卷 158-163,I0006页

作者： si-qi Teng Zhi-Guo Jiang Zhao-Bin qiu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Two octaisobutyl-polyhedral oligomeric silsesquioxanes(oib-POSS)reinforced biodegradable poly(ε-caprolactone)(PCL)composites were prepared via two different methods,i.e.,melt compounding and solution casting,which were named as m PCL/oib-POSS and s PCL/oibPOSS,respectively,in this ***-POSS dispersed finely in both composites;moreover,oib-POSS aggregates were larger in m PCL/oib-POSS than in s PCL/*** the different preparation methods,oib-POSS obviously promoted the crystallization of PCL,especially in s PCL/oib-POSS,but did not modify the crystal structure of *** storage moduli of PCL were improved significantly in both ***/oib-POSS composites with enhanced crystallization behavior and improved dynamic mechanical properties were successfully prepared through both methods;moreover,the solution casting method was more effective than the melt compounding method.

关键词： Poly(ε-caprolactone) POSS Crystallization

Structural Manipulation of Aminal-crosslinked Polybutadiene for Recyclable and Healable Elastomers

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Chinese Journal of Polymer Science 2021年第10期39卷 1337-1344,I0008页

作者： Zheng-Hai Tang Hui Zeng si-qi Wei si-Wu Wu Bao-Chun Guo Department of Polymer Materials and Engineering South China University of TechnologyGuangzhou 510640China

Recently,increasingly growing efforts have been devoted to incorporating dynamic covalent bonds into covalently crosslinked networks to address the persistent trade-offs between chemical crosslinking and ***,a series of dynamic aminal bond crosslinked polybutadiene rubbers(PAPB)are prepared by crosslinking aldehyde group-terminated polybutadiene rubber(APB)with *** varying the molecular weight of APB,the crosslinking density of PAPB is changed,which offers the platform to regulate the mechanical characteristics and dynamic ***,with the decrease of APB molecular weight,*** the increase of crosslinking density,the modulus of PAPB gradually increases while the elongation at break conversely decreases,and the activation energy for network rearrangement initially decreases and then *** resultant PAPB exhibit vitrimer-like behaviors that can alter the network topologies at elevated temperatures without the loss of structural integrity through dissociative aminal exchange reactions,while the protic source can accelerate aminal dissociation and result in network dissolution even at room *** to the aminal exchange,PAPB are thermally malleable and can almost restore the original mechanical characteristics after recycling;besides,they are capable of healing at a relatively low crosslinking density.

关键词： Aminal Recyclability Healing Structural manipulation Dynamic covalent network

Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： ye TIAN Tielin SHI qi XIA State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

Regional Equity and Influencing Factor of Social Assistance in China

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Chinese Geographical Science 2021年第4期31卷 611-628页

作者： WANG Jiawei ye Shilin qi Xinhua State Key Laboratory for Subtropical Mountain Ecology of the Ministry of Science and Technology and Fujian Province Fujian Normal UniversityFuzhou 350007China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China

Social assistance is the last safety net in the social security system and plays a vital role in poverty alleviation in countries around the world. Promoting the equal financial assistance is meaningful to achieve equalization of social assistance. Based on the provincial panel data from 2002 to 2017, this paper analyzes the dynamic characteristics and main influencing factors of the equity of social assistance in China, using the Theil index and geographically weighted regression(GWR) model. The results suggest that the level of per capita social assistance expenditure(PSAE) in China keeps increasing year by year, but the changes in different regions and provinces are quite different. These changes not only significantly changed the spatial pattern of PSAE in China, but also greatly improved its spatial coupling with the deeply impoverished areas. Further analysis shows that the regional inequality of PSAE between provinces is obvious during the study period, and the inter-regional inequality is significantly higher than the intra-regional *** makes inter-regional inequality become the main source of the regional inequality of PSAE in China for a long time. According to GWR results, there is obvious spatiotemporal heterogeneity in the influence intensity and direction of the per capita financial revenue,urbanization rate, urban unemployment rate, natural disaster-affected area, and transfer payment intensity on the PSAE. The urbanization rate and per capita financial revenue are the main driving factors of PSAE, and the impact intensity of per capita financial revenue tends to strengthen. The remaining three factors have a positive effect on PSAE, but the effect intensity is not high.

关键词： social assistance regional equity spatiotemporal pattern poverty alleviation influencing factors China

A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-qi Yu Tao Yu Jian-Hua ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Removal of pharmaceutical in a biogenic/chemical manganese oxide system driven by manganese-oxidizing bacteria with humic acids as sole carbon source

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Journal of Environmental Sciences 2023年第4期126卷 734-741页

作者： Tingming ye Huijuan Liu Weixiao qi Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China University of Chinese Academy of Sciences Beijing 100049China

Bioaugmented sand filtration has attracted considerable attention because it can effectively remove contaminants in drinking water without additional chemical reagent *** this study,a synthesized chemical manganese dioxide (MnO_(2)) -coated quartz sand(MnQS) and biogenic manganese oxide (BioMnOx) composite system was proposed to simultaneously remove typical pharmaceutical contaminants and Mn_(2)+.We demonstrated a manganese-oxidizing bacterium,Pseudomonas ***-1,could oxidize Mn_(2)+to generate BioMnOxusing humic acids (HA) as sole carbon *** coaction of MnQS,QJX-1,and the generated BioMnOxin simultaneously removing caffeine and Mn_(2)+in the presence of HA was *** found a synergistic effect between *** and BioMnOxtogether significantly increased the caffeine removal efficiency from 32.8%(MnQS alone) and 21.5%(BioMnOxalone) to 61.2%.Meanwhile,Mn_(2)+leaked from MnQS was rapidly oxidized by QJX-1 to regenerate reactive BioMnOx,which was beneficial for continuous contaminant removal and system *** degradation intermediates of caffeine oxidized by MnQS and BioMnOxwere detected by LC-QTOF-MS analysis,which implied that caffeine was oxidized by a different ***,this work promotes the potential application of bioaugmented sand filtration in pharmaceutical removal in the presence of natural organic matter in drinking water.

关键词： Bioaugmentation MnO_(2)-coated quartz sand Manganese-oxidizing bacteria Humic acid Caffeine

PV Array Reconfiguration Based on the Shaded Cells'Number for PV Modules

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 733-742页

作者： Jun qi Xun Huang Beijia ye Dan Zhou College of Information Engineering Zhejiang University of TechnologyHangzhou 310014China

Reconfiguration can increase the output power for a PV array under partial ***,traditional reconfiguration methods consider the PV module as either totally shaded or totally unshaded,and module-based simulation is employed to evaluate the reconfiguration ***,there is an unneglectable error when treating a partially shaded PV module as totally shaded,through using a more accurate cellbased *** on the analysis of the determinant factors on MPPs’power of a PV array,a new reconfiguration method is proposed based on the exact partial shadow shape projected on the PV *** method restructures the electrical connection among PV modules of a PV array according to the shaded cells’number(SCN)of every PV *** cell-based simulations are carried out on a PV array to verify the effectiveness of the proposed SCN-based reconfiguration *** comparisons among various reconfiguration methods and shadow distributions clearly show its suitability to different irregular shadows and its superiority in PV output power enhancement.

关键词： Maximum power point(MPP) partial shadow PV array PV module reconfiguration

Filters for manufacturability in design optimization of variable stiffness composites

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Chinese Journal of Aeronautics 2021年第4期34卷 153-159页

作者： ye TIAN Yuhang HUO Tielin SHI qi XIA State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China

In the design optimization of variable stiffness composites,manufacturing constraints imposed by the automated fiber placement technology must be *** the present paper,two filters are proposed to address this issue,and they are incorporated into the Shepard interpolation-based design optimization framework developed in our previous *** fiber angle arrangement of a composite is represented by a continuous function that interpolates fiber angles at scattered design *** filters are appointed for each design point to deal with two typical manufacturing constraints,i.e.,fiber curvature and gap/*** each design point,the sensitivity is first filtered in a rectangular region around this point,and by this means the fiber curvature is controlled;then in another rectangular region around this design point,the filtered sensitivities are averaged,and the result is used to update the corresponding design *** numerical examples are investigated,and the results show that the proposed method is effective.

关键词： Composite laminates Design optimization Fiber angle Filter Manufacturing constraints

Image De-occlusion via Event-enhanced Multi-modal Fusion Hybrid Network

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Machine Intelligence Research 2022年第4期19卷 307-318页

作者： si-qi Li Yue Gao qiong-Hai Dai Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Institute for Brain and Cognitive Sciences Tsinghua UniversityBeijing 100084China Beijing Laboratory of Brain and Cognitive Intelligence Beijing Municipal Education CommissionTsinghua UniversityBeijing 100084China Key Laboratory for Information System Security School of SoftwareTsinghua UniversityBeijing 100084China Department of Automation Tsinghua UniversityBeijing 100084China

Seeing through dense occlusions and reconstructing scene images is an important but challenging *** framebased image de-occlusion methods may lead to fatal errors when facing extremely dense occlusions due to the lack of valid information available from the limited input occluded *** cameras are bio-inspired vision sensors that record the brightness changes at each pixel asynchronously with high temporal ***,synthesizing images solely from event streams is ill-posed since only the brightness changes are recorded in the event stream,and the initial brightness is *** this paper,we propose an event-enhanced multi-modal fusion hybrid network for image de-occlusion,which uses event streams to provide complete scene information and frames to provide color and texture *** event stream encoder based on the spiking neural network(SNN)is proposed to encode and denoise the event stream efficiently.A comparison loss is proposed to generate clearer *** results on a largescale event-based and frame-based image de-occlusion dataset demonstrate that our proposed method achieves state-of-the-art performance.

关键词： Event camera multi-modal fusion image de-occlusion spiking neural network(SNN) image reconstruction

A general solution for Stokes flow and its application to the problem of a rigid plate translating in a fluid

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Acta Mechanica sinica 2015年第1期31卷 32-44页

作者： Xiang-Yu Li si-Cong Ren qi-Chang He School of Mechanics and Engineering Southwest Jiaotong University School of Mechanical Engineering Southwest Jiaotong University Universit'e Paris-Est Laboratoire Mod'elisation et Simulation Multi Echelle UMR 8208 CNRS 5 Boulevard Descartes77454 Marne-la-Vall'ee France

A general solution for 3D Stokes flow is given which is different from, and more compact than the exist ing ones and more compact than them in that it involves only two scalar harmonic functions. The general solution deduced is combined with the potential theory method to study the Stokes flow induced by a rigid plate of arbitrary shape trans lating along the direction normal to it in an unbounded fluid. The boundary integral equation governing this problem is derived. When the plate is elliptic, exact analytical results are obtained not only for the drag force but also for the ve locity distributions. These results include and complete the ones available for a circular plate. Numerical examples are provided to illustrate the main results for circular and ellip tic plates. In particular, the elliptic eccentricity of a plate is shown to exhibit significant influences.

关键词： Stokes flow 3D general solutions Potentialtheory method Circular plate Elliptic plate