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Enhancing the Crystallization Performance of Poly(L-lactide) by Intramolecular Hybridizing with Tunable Self-assembly-type Oxalamide Segments

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Chinese Journal of Polymer Science 2021年第1期39卷 122-132,I0008页

作者： man-man Yu Wei-Jun yang De-Yu Niu Xiao-Xia Cai Yun-Xuan Weng Wei-fu Dong Ming-Qing Chen Peng-Wu Xu yang Wang Hong Chu Pi-Ming Ma The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics Beijing Technology and Business UniversityBeijing 100048China

In this work, hydroxyl-terminated oxalamide compounds N^(1),N^(2)-bis(2-hydroxyethyl)oxalamide(OXA1) and N^(1),N^(1)′-(ethane-1,2-diyl)bis(N^(2)-(2-hydroxyethyl)oxalamide(OXA2) were synthesized to initiate the ring-opening polymerization of L-lactide for preparation of oxalamide-hybridized poly(L-lactide)(PLA_(OXA)), i.e., PLA_(OXA1) and PLA_(OXA2). The crystallization properties of PLA were improved by the self-assembly of the oxalamide segments in PLA_(OXA) which served as the initial heterogeneous nuclei. The crystal growth kinetics was studied by HoffmanLauritzen theory and it revealed that the nucleation energy barrier of PLA_(OXA1) and PLA_(OXA2) was lower than that of PLA. Consequently, PLA_(OXA) could crystallize much faster than PLA, accompanied with a decrease in spherulite size and half-life crystallization time by 74.8% and 86.5%(T=125 ℃), respectively. In addition, the final crystallinity of PLA_(OXA1) and PLA_(OXA2) was 6 and 8 times higher, respectively, in comparison with that of neat PLA under a controlled cooling rate of 10 ℃/min. The results demonstrate that the hybridization of oxalamide segments in PLA backbone will serve as the self-heteronucleation for promoting the crystallization rate. The higher the content of oxalamide segments(PLA_(OXA2) compared with PLA_(OXA1)) is, the stronger the promotion effect will be. Therefore, this study may provide a universal approach by hybridizing macromolecular structure to facilitate the crystallization of semi-crystalline polymer materials.

关键词： Poly(L-lactide) Oxalamide compounds Self-heteronucleation Crystallization kinetics

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关注学习路上的慢跑者——苏霍姆林斯基“学困生”教育思想及启示

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兵团教育学院学报 2025年第1期35卷 56-64页

作者：王福关满姗翟玉洁石河子大学师范学院/兵团教育学院新疆石河子832003 石河子大学师范学院新疆石河子832003

苏霍姆林斯基在长期的教育实践中,形成了其独特的学困生教育观。本研究基于苏霍姆林斯基关于学困生的教育思想,主要从学校教育和家庭教育两方面分析了学困生的成因,并提出了相应的转化策略。苏霍姆林斯基的教育思想对当下学困生教育有... 详细信息

苏霍姆林斯基在长期的教育实践中,形成了其独特的学困生教育观。本研究基于苏霍姆林斯基关于学困生的教育思想,主要从学校教育和家庭教育两方面分析了学困生的成因,并提出了相应的转化策略。苏霍姆林斯基的教育思想对当下学困生教育有着重要启示,应让学生养成良好的学习习惯和学习的自觉性,构建学校的全面育人系统,强化教师的主导作用,引导学困生发挥自我转化的主体作用。

关键词：学困生苏霍姆林斯基转化策略启示

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Modified artificial neural network model with an explicit expression to describe flow behavior and processing maps of Ti2AlNb-based superalloy

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Journal of Iron and Steel Research International 2021年第11期28卷 1451-1462页

作者： Yan-qi fu Qing Zhao man-qian Lv Zhen-shan Cui School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Institute of Forming Technology and Equipment Shanghai Jiao Tong UniversityShanghai 200030China

The elevated-temperature deformation behavior of Ti2AlNb superalloy was observed by isothermal compression experiments in a wide range of temperatures(950–1200°C)and strain rates(0.001–10 s^(-1)).The flow behavior is nonlinear,strongly coupled,and *** constitutive models,namely the double multivariate nonlinear regression model,artificial neural network model,and modified artificial neural network model with an explicit expression,were applied to describe the Ti2AlNb superalloy plastic deformation *** comparative predictability of those constitutive models was further evaluated by considering the correlation coefficient and average absolute relative *** comparative results show that the modified artificial network model can describe the flow stress of Ti2AlNb superalloy more accurately than the other developed constitutive *** explicit expression obtained from the modified artificial neural network model can be directly used for finite element *** modified artificial neural network model solves the problems that the double multivariate nonlinear regression model cannot describe the nonlinear,strongly coupled,and multivariable flow behavior of Ti2AlNb superalloy accurately,and the artificial neural network model cannot be embedded into the finite element software ***,the modified artificial neural network model is mainly dependent on the quantity of high-quality experimental data and characteristic variables,and the modified artificial neural network model has not physical ***,the processing maps were applied to obtain the optimum processing parameters.

关键词： Modified artificial neural network model Ti2AlNb superalloy Double multivariate nonlinear regression model Explicit expression Processing map

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Revealing component synergy of Ni‒Fe/black phosphorous composites synthesized by self-designed electrochemical method for enhancing photoelectrocatalytic oxygen evolution reaction

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Frontiers of Materials Science 2023年第2期17卷 143-153页

作者： He Xiao Shoufeng Xue Zimei fu man Zhao Li Zhang Junming Zhang Haishun Wu Jianfeng Jia Nianjun yang Key Laboratory of Magnetic Molecules&Magnetic Information Materials(Ministry of Education) School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuan 030032China Department of Chemistry Hasselt University3590 DiepenbeekBelgium

Developing high-activity and low-cost catalysts is the key to eliminate the limitation of sluggish anodic oxygen evolution reaction(OER)during electrocatalytic overall water ***,Ni‒Fe/black phosphorous(BP)composites are synthesized using a simple three-electrode system,where exfoliation of bulky BP and synthesis of NiFe composites are simultaneously *** light illumination,the optimized Ni‒Fe/BP composite exhibits excellent photoelectrocatalytic OER performance(e.g.,the overpotential is 58 mV lower than a commercial RuO_(2) electrocatalyst at a current density of 10 mA·cm^(-2)).The electron transfer on this composite is proved to follow a Ni‒BP‒Fe *** electronic structure of this Ni‒Fe/BP composite is effectively regulated,leading to optimized adsorption strength of the intermediate OH*and improved intrinsic activity for the *** with active sites on the support,this Ni‒Fe/BP composite possesses abundant electrochemical active sites and a bug surface area for the *** introduction of light further accelerates the electrocatalytic *** work provides a novel and facile method to synthesize high-performance metal/BP composites as well as the approaches to reveal their OER mechanisms.

关键词： black phosphorous (photo-)electrocatalysis oxygen evolution reaction

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An improved image blind deblurring based on dark channel prior

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Optoelectronics Letters 2021年第1期17卷 40-46页

作者： WANG man-wei ZHU fu-zhen BAI Yu-yang College of Electronic Engineering Heilongjiang UniversityHarbin 150000China

In order to solve the ringing effect caused by the incorrect estimation of the blur kernel, an improved blind image deblurring algorithm based on the dark channel prior is proposed. First, in the blur kernel estimation stage, high-pass filtering is introduced to enhance the image quality and enhance the edge information to make the blur kernel estimation more accurate. A combination of super Laplacian prior and dark channel prior is introduced to estimate the potential clear image. Then the accurate blur kernel is estimated through alternate iterations from coarse to fine. In the image restoration stage, a weighted least square filter is introduced to suppress the ringing effect of the original clear image to further improve the quality of image restoration. Finally, image deconvolution based on Laplace priors and L_(0) regularized priors is used to restore clear images. Experimental results show that our approach improves the peak signal-to-noise ratio(PSNR) by about 0.4 d B and structural similarity(SSIM) by about 0.01, respectively. Compared with the existing image deblurring algorithms, this method can estimate the blur information more accurately, so that the restored image can achieve the effect of keeping the edges and removing ringing.

关键词： image kernel estimation

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Corrosion behavior of a spark plasma sintered Fe-2OMn-11Al-1.8C- 5Cr alloy in molten aluminum

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Journal of Iron and Steel Research International 2018年第5期25卷 563-571页

作者： Jian Liu Wei-ping Chen Xian-man Zhang Zhi-qiang fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640 Guangdong China College of Engineering and Technology Normal College ofZunyi Zunyi 563006 Guizhou China Mechanical and Electrical Engineering College Hainan University Haikou 570228 Hainan China

The corrosion behavior of an Fe-20Mn-11Al-1.8C-5Cr alloy prepared by spark plasma sintering was investigated via immersion tests in molten aluminum at 750℃ for 1 and 4 h, respectively, and a hot work steel （AlSI H13） was included as a reference. The experimental results show that the corrosion rate of Fe-20Mn-11Al-1.8C-5Cr alloy is - 24% of that of H13 steel, suggesting that Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum possesses better corrosion resistance than H13 steel. Detailed analysis show that k-carbide （（Fe, Mn）3AlCx） and Cr7C3 carbide precipitated in the matrix play a key role in enhancing the corrosion resistance of Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum. Both of them show better corrosion resistance than 7-Fe matrix and H13 steel, and can also take on the role of roots in grasping the corrosion product and restrain them from spalling into the molten aluminum.

关键词： Fe-Mn-Al-C-Cr alloy · Molten aluminum. Immersion · Corrosion behavior

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Reduction behavior and mechanism of Hongge vanadium titanomagnetite pellets by gas mixture of H2 and CO

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Journal of Iron and Steel Research International 2017年第1期24卷 34-42页

作者： Wei Li Gui-qin fu man-sheng Chu Miao-yong Zhu School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Hongge vanadium titanomagnetite（HVTM）pellets were reduced by H2-CO gas mixture for simulating the reduction processes of Midrex and HYL-III shaft *** influences of reduction temperature,ratio ofφ（H2）toφ（CO）,and pellet size on the reduction of HVTM pellets were evaluated in detail and the reduction reaction kinetics was *** results show that both the reduction degree and reduction rate can be improved with increasing the reduction temperature and the H2 content as well as decreasing the pellet *** rational reduction parameters are reduction temperature of 1050℃,ratio ofφ（H2）toφ（CO）of 2.5,and pellet diameter in the range of 8-11 *** these conditions（pellet diameter of 11mm）,final reduction degree of 95.51% is *** X-ray diffraction（XRD）pattern shows that the main phases of final reduced pellets under these conditions（pellet diameter of 11 mm）are reduced iron and *** peak intensity of reduced iron increases obviously with the increase in the reduction ***,relatively high reduction temperature promotes the migration and coarsening of metallic iron particles and improves the distribution of vanadium and chromium in the reduced iron,which is conducive to subsequent melting *** the early stage,the reduction process is controlled by interfacial chemical reaction and the apparent activation energy is 60.78kJ/*** reduction process is controlled by both interfacial chemical reaction and internal diffusion at the final stage,and the apparent activation energy is 30.54kJ/mol.

关键词： Hongge vanadium titanomagnetite Pellet Gas-based direct reduction Behavior and mechanism Kinetics

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Bibliometric Review of Biodiversity Offsetting During 1992-2019

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Chinese Geographical Science 2022年第2期32卷 189-203页

作者： YU Shuling CUI Baoshan XIE Chengjie man Ying fu Jing State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China Yellow River Estuary Wetland Ecosystem Observation and Research Station Ministry of EducationDongying 257500China East China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesShanghai 200090China

Biodiversity offsetting plays a crucial role in managing the impacts of development on natural habitats. Developers, conservation groups, governments and financial institutions have used biodiversity offsetting to design measurable conservation actions to compensate for significant residual adverse biodiversity impacts arising from development. However, the concepts and methodologies of biodiversity offsetting have rarely been systematically reviewed, and best practices are still lacking. This hinders the development and applications of this field, and makes it difficult for new researchers to learn, develop, and apply biodiversity offsetting. This paper aims to review research progress on biodiversity offsetting during the period of 1992 to 2019. We mainly used bibliometric analysis and social network analysis methods to expose the topic diversity, development and promotion of this research field, and assess collaboration among biodiversity offsetting scholars. Our research identified 1190 records, and revealed that the total number of publications increased rapidly since 2002. The most productive journal, country, and author were Biological Conservation, USA, and Dr. Maron M of University of Queensland, respectively. Co-author analysis identified that the 23 authors most relevant to biodiversity offsetting were involved in a collaboration network. And they were mainly from 30 countries in a collaboration network, and the authors from USA, Australia and the United Kingdom have the most cooperation, which mainly driven by policy related to biodiversity offsetting. Our review shows that biodiversity offsetting research is at an early stage of rapid development with topically diverse and collaborative science domains. The majority of studies focus on terrestrial environments, which makes the implementation of aquatic ecosystem is more difficult. Theoretical problems and the implications of research evolution and social network in biodiversity offsetting are discussed,

关键词： academic influence biodiversity offsetting compensation bibliometric analysis social network analysis

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Asymmetric Synthesis of the Ring A Substructure of Genkwadane A

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Chinese Journal of Chemistry 2018年第9期36卷 831-836页

作者： Jing Feng Hongli Yin Yi man Shaomin fu BO Liu Key Laboratory of Green Chemistry & Technology of Ministry of Education College of Chemistry Sichuan University Chengdu Sichuan 610064China

A practical approach to the asymmetric synthesis of the ring A substructure of genkwadane A, a daphnane diterpenoid, was developed. This synthesis features the Mukaiyama aldol reaction to introduce the quaternary stereogenic center at C4 and VO（acac）2-catalyzed Jackson-Ellman-Bolrn sulfoxidation to deliver the corresponding sulfoxide. The Dieckmann-type condensation was efficiently promoted by KHMDS and the ring A substructure was finally accomplished through Barton iodination condition.

关键词： genkwadane A daphnane Mukaiyama aldol sulfoxidation Dieckmann-type condensation

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The diversity of soil culturable fungi in the three alpine shrub grasslands of Eastern Qilian Mountains

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Frontiers of Earth Science 2013年第1期7卷 76-84页

作者： Junzhong ZHANG Baiying man Benzhong fu Li LIU Changzhi HAN Key Laboratory of Forest Disaster Warning and Control in Yunnan Province College of Forestry Southwest Forestry University Kunming 650224 China Sontan college Guangzhou University Guangzhou 511370 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China

To understand the diversity of culturable fungi in soil at alpine sites, Rhododendron fruticosa shrubland, Salix cupularis fruticosa shrubland, and Dasiphoru fruticosa shrubland of the Eastern Qilian Mountains were selected to investigate. Three methods, including tradi- tional culturing, rDNA internal transcribed spacer （ITS） sequence analysis, and economical efficiency analysis, were carried out to estimate the diversity of soil culturable fungi of these three alpine shmblands. A total of 35 strains of culturable fungi were cultured by dilution plate technique and were analyzed by rDNA ITS sequence. The diversity indices such as species abundance （S）, Shannon-Wiener index （H）, Simpson dominance index （D）, and Pielou evenness index （3） of Rhododendron fruticosa shrubland, Salix cupularis fruticosa shrubland, and Dasiphoru fruticosa shrubland were ranged between 16 and 17, 2.66-2.71, 0.92, 0.95~）.97 respectively. The results showed that the diversity of soil fungi were abundant in these three types of alpine shrub grasslands, while further study should be done to explore their potential value.

关键词： alpine shrub grasslands culturable fungi rDNA ITS sequence analysis diversity

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