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Journal of Materials Science and Chemical Engineering 2025年第1期13卷 20-44页

作者： Hao duan Xiaoyan Shang Xihao Wu Liuliu Ma Chen Xing Jun Zhu Department of Materials Science Fudan University Shanghai China Fineblend Polymer (Shanghai) Co. Ltd. Shanghai China National Engineering Research Center for Nanotechnology Shanghai China

Amid the escalating plastic pollution issue, the development of biodegradable and recyclable polymeric materials has become a focus within the scientific community. Chain extenders, which are an important class of compounds, facilitate the elongation of polymer chains through reactive functional groups, thereby enhancing the performance of the materials. Epoxy-based chain extenders, due to their cost-effectiveness, low toxicity, high reaction efficiency, and effective reactivity with hydroxyl and carboxyl groups, have emerged as a promising class of chain extenders. This manuscript comprehensively elaborates on the varieties, structural characteristics, and performance of chain extenders, the challenges they face, and the methods for their modification. Special emphasis is placed on the application of epoxy-based chain extenders in biodegradable polymers, such as polylactic acid (PLA), and their subsequent influence on the structural and performance properties of these materials.

关键词： Chain Extender Epoxy Type GMA Biodegradable PLA Recycle

A Review:From Aquatic Lives Locomotion to Bio-inspired Robot Mechanical Designations

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Journal of Bionic Engineering 2023年第6期20卷 2487-2511页

作者： Pengxiao bao Liwei Shi Lijie duan Shuxiang Guo Zhengyu Li School of Medical Technology Beijing Institute of TechnologyBeijing100081China School of Life Science Beijing Institute of TechnologyBeijing100081China The Key Laboratory of Convergence Medical Engineering System and Healthcare Technology The Ministry of Industry and Information TechnologyBeijing Institute of TechnologyNo.5ZhongguancunSouth StreetBeijing100081China The Department of Electronic and Electrical Engineering Southern University of Science and TechnologyShenzhen518055GuangdongChina

With the development of camera technology,high-speed cameras have greatly contributed to capturing the movement and posture of animals,which has dramatically promoted experimental biology *** the same time,with the concept of bionics gradually gaining popularity among researchers,the design of robots is absorbing more and more biological features,where the interest in the bio-inspired robot is hewed *** with the traditional robot,the bio-inspired robot imitates the motion pattern to achieve similar propulsion features,which may be more effective and *** this paper,the motion patterns of aquatic animals are divided into four categories according to their propulsion mechanisms:drag-based,lift-based,jet-based,and *** bio-inspired robots imitating aquatic prototypes are introduced and ***,the prospect of aquatic bio-inspired robots is discussed.

关键词： Bionic Bio-inspired robot Aquatic animal Propelling mechanism Structure design

H_∞ CONTROL OF NETWORKED MULTI-AGENT SYSTEMS

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Journal of Systems Science & Complexity 2009年第1期22卷 35-48页

作者： Zhongkui LI Zhisheng duan lin HUANG State Key Lab for Turbulence and Complex Systems and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China.

This paper concerns the disturbance rejection problem arising in the coordination control of a group of autonomous agents subject to external disturbances. The agent network is said to possess a desired level of disturbance rejection, if the H∞ norm of its transfer function matrix from the disturbance to the controlled output is satisfactorily small. Undirected graph is used to represent the information flow topology among agents. It is shown that the disturbance rejection problem of an agent network can be solved by analyzing the H∞ control problem of a set of independent systems whose dimensions are equal to that of a single node. An interesting result is that the disturbance rejection ability of the whole agent network coupled via feedback of merely relative measurements between agents will never be better than that of an isolated agent. To improve this, local feedback injections are applied to a small fraction of tile agents in the network. Some criteria for possible performance improvement are derived in terms of linear matrix inequalities. Finally, extensions to the case when communication time delays exist are also discussed.

关键词： Coordination control graph theory H∞ control linear matrix inequality (LMI) pinning control.

Surgical treatment of four segment lumbar spondylolysis:A case report

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World Journal of Clinical Cases 2021年第17期9卷 4408-4414页

作者： duan-Ming Li bao-Gan Peng Department of Orthopedics The Third Medical Center of People's Liberation Army General HospitalBeijing 100039China

Four-level lumbar spondylolysis is extremely *** far,only 1 case has been reported in the *** SUMMARY A 19-year-old man presented with severe back pain irresponsive to conservative therapies for 2 *** radiographs and two-dimensional computed tomography scan showed four segment lumbar spondylolysis on both sides of *** magnetic resonance imaging showed normal signal in all lumbar *** daily activities were severely limited,surgery was recommended for the *** patient underwent four-level bilateral isthmic repair at *** surgery,L2-L5 isthmi were curetted bilaterally,freshened,and then grafted with autologous iliac bone that was bridged and compressed with a pedicular screw connected to a sub-laminar hook by a short *** symptoms of back pain almost *** has been followed-up for 96 mo,and his symptoms have never *** was found in all repaired isthmi 14 mo after surgery according to evaluation of lumbar radiography and computed tomography *** We report here 1 case of four-level lumbar spondylolysis that was treated successfully with direct isthmic repair.

关键词： Lumbar spondylolysis Isthmic repair Pedicle screw-hook system Case report

Biodegradation of 2-methylquinoline by Enterobacter aerogenes TJ-D isolated from activated sludge

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Journal of Environmental Sciences 2013年第7期25卷 1310-1318页

作者： lin Wang Yongmei Li Jingyuan duan State Key Laboratory of Pollution Control and Resource Reuse Tongji University

Bacterial strain Enterobacter aerogenes TJ-D capable of utilizing 2-methylquinoline as the sole carbon and energy source was isolated from acclimated activated sludge under denitrifying conditions. The ability to degrade 2-methylquinoline by E. aerogenes TJ-D was investigated under denitrifying conditions. Under optimal conditions of temperature （35°C） and initial pH 7, 2-methylquinoline of 100 mg/L was degraded within 176 hr. The degradation of 2-methylquinoline by E. aerogenes TJ-D could be well described by the Haldane model （R 2 〉 0.91）. During the degradation period of 2-methylquinoline （initial concentration 100 mg/L）, nitrate was almost completely consumed （the removal efficiency was 98.5%）, while nitrite remained at low concentration （〈 0.62 mg/L） during the whole denitrification period. 1,2,3,4-Tetrahydro-2-methylquinoline, 4-ethyl-benzenamine, N-butyl-benzenamine, N-ethyl-benzenamine and 2,6-diethyl-benzenamine were metabolites produced during the degradation. The degradation pathway of 2-methylquinoline by E. aerogenes TJ-D was proposed. 2-Methylquinoline is initially hydroxylated at C-4 to form 2-methyl-4-hydroxy-quinoline, and then forms 2-methyl-4-quinolinol as a result of tautomerism. Hydrogenation of the heterocyclic ring at positions 2 and 3 produces 2,3-dihydro-2-methyl-4-quinolinol. The carbon-carbon bond at position 2 and 3 in the heterocyclic ring may cleave and form 2-ethyl-N-ethyl-benzenamine. Tautomerism may result in the formation of 2,6-diethyl-benzenamine and N-butyl-benzenamine. 4- Ethyl-benzenamine and N-ethyl-benzenamine were produced as a result of losing one ethyl group from the above molecules.

关键词： biodegradation Enterobacter aerogenes TJ-D 2-methylquinoline denitrifying conditions activated sludge

Construction of controllable size silver nanoparticles immobilized on nanofibers of chitin microspheres via green pathway

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Nano Research 2016年第7期9卷 2149-2161页

作者： lin Guo Bo duan lina Zhang College of Chemistry & Molecule Sciences Wuhan University Wuhan 430072 China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

In the present work, nanofibrous chitin microsphere （NCM） was prepared via sol-gel transition from a chitin solution dissolved in a NaOH/urea aqueous system at low temperatures. Ag nanoparticles （AgNPs） were synthesized via an in situ reduction of silver nitrate using trisodium citrate dehydrate and were immobilized on chitin nanofibers to obtain composite microspheres that consist of nanofibers and AgNPs （NCM-Ag）. The size of AgNPs could be controlled in the range of 10 to 70 nm, depending on the concentration of AgNO3. X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared （FT-IR） analyses showed that the chitin nanofibers have a strong affinity toward AgNPs, resulting from the interaction between the acetamino group of chitin and the AgNPs. The NCM-Ag exhibited a perfect nanoporous structure and high surface area, as well as high stability in organic solvents. Moreover, in the catalytic epoxidation of olefin （particularly, the conversion of styrene to styrene epoxide）, NCM-Ag exhibited an excellent selectivity of up to 90%. Converting chitin powder into chitin microspheres using an environmentally friendly technique is a green process, which is beneficial for the large-scale synthesis of industrial products. More importantly, this work provides a green synthetic pathway for the construction of size-controlled noble metal nanoparticles immobilized on nanofiber support, which have a wide range of potential applications.

关键词： chitin microsphere nanofibers immobilization of silvernanoparticles selective epoxidation controllable nano-size

Comparative transcriptome analysis identifies key regulators of nitrogen use efficiency in chrysanthemum

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Journal of Integrative Agriculture 2025年第1期24卷 176-195页

作者： Lijiao Ge Weihao Miao Kuolin duan Tong Sun Xinyan Fang Zhiyong Guan Jiafu Jiang Sumei Chen Weimin Fang Fadi Chen Shuang Zhao College of Horticulture Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Landscaping Ministry of Agriculture and Rural AffairsNanjing 210095China Jiangsu Yanjiang Institute of Agricultural Sciences Nantong 226012China

Nitrogen(N)is a limiting factor that determines the yield and quality of *** variation in N use efficiency(NUE)has been reported among chrysanthemum *** performed a transcriptome analysis of two chrysanthemum genotypes,'Nannonglihuang'(LH,N-efficient genotype)and'Nannongxuefeng"(XF,N-inefficient genotype),under low N(0.4 mmol L^(-1)N)and normal N(8 mmol L^(-1)N)treatments for 15 d and an N recovery treatment for 12 h(low N treatment for 15 d and then normal N treatment for 12 h)to understand the genetic factors impacting NUE in *** two genotypes exhibited contrasting responses to the different N *** N-efficient genotype LH had significant superiority in agronomic traits,N accumulation and glutamine synthase activity under both normal N and low N *** N treatment promoted root growth in LH,but inhibited root growth in *** analysis revealed that the low N treatment increased the expression of some N metabolism genes,genes related to auxin and abscisic acid signal transduction in the roots of both genotypes,as well as genes related to gibberellin signal transduction in roots of *** N recovery treatment just increased the expression of genes related to cytokinin signal transduction in roots of *** expression levels of the NRT2.1,AMT1.1,and Gln1 genes related to gibberellin and cytokinin signal transduction were higher in roots of LH than in XF under different N treatments,suggesting that the genes related to N metabolism and hormone(auxin,abscisic acid,gibberellin,and cytokinin)signal transduction in roots of LH are more sensitive to different N treatments than those of ***-expression network analysis(WGCNA)also identified hub genes like bZIP43,bHLH93,NPF6.3,IBR10,MYB62,PP2C,PP2C06 and NLP7,which may be the key regulators of N-mediated responses in chrysanthemum and play crucial roles in enhancing NUE and resistance to low N stress in the N-efficient chrysanthemum *** results r

关键词： chrysanthemum genotype NUE gene expression transcriptome analysis

The shifts of precipitation phases and their impacts

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Science China Earth Sciences 2025年第2期68卷 425-443页

作者： Xuemei LI Tao CHE Yuanlong TANG Huan’e duan Guigang WANG Xu ZHANG Chuanming YANG Jun WU Yue ZHANG Lanhai LI Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Lanzhou 730070China Key Laboratory of Science and Technology in Surveying&Mapping Gansu Province Lanzhou 730070China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese academy of SciencesUrumqi 830011China Tianshan Snow Cover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China

Precipitation comes in various phases, including rainfall, snowfall, sleet, and hail. Shifts of precipitation phases, as well as changes in precipitation amount, intensity, and frequency, have significant impacts on regional climate, hydrology,ecology, and the energy balance of the land-atmosphere system. Over the past century, certain progress has been achieved in aspects such as the observation, discrimination, transformation, and impact of precipitation phases. Mainly including: since the1980s, studies on the observation, formation mechanism, and prediction of precipitation phases have gradually received greater attention and reached a certain scale. The estimation of different precipitation phases using new detection theories and methods has become a research focus. Avariety of discrimination methods or schemes, such as the potential thickness threshold method of the air layer, the temperature threshold method of the characteristic layer, and the near-surface air temperature threshold method,have emerged one after another. Meanwhile, comparative studies on the discrimination accuracy and applicability assessment of multiple methods or schemes have also been carried out simultaneously. In recent years, the shift of precipitation from solid to liquid(SPSL) in the mid-to-high latitudes of the Northern Hemisphere has become more pronounced due to global warming and human activities. It leads to an increase in rain-on-snow(ROS) events and avalanche disasters, affecting the speed, intensity, and duration of spring snow-melting, accelerating sea ice and glacier melting, releasing carbon from permafrost, altering soil moisture, productivity, and phenological characteristics of ecosystems, and thereby affecting their structures, processes, qualities, and service functions. Although some progress has been made in the study of precipitation phases, there remains considerable research potential in terms of completeness of basic data, reliability of discrimination schemes, a

关键词： Precipitation phases Shift of precipitation from solid to liquid(SPSL) Climate change Water cycle processes Snowandicepr sses Snow and ice-related disasters Carbon emission from permafrost Ecosystems

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CORRESPONDENCE ANALYSIS ON IMAGES OF JIANGXI PROVINCE AS A TOURIST DESTINATION

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Chinese Geographical Science 2005年第3期15卷 275-280页

作者： MAO duan-qian ZHANG Jie bao Hao-sheng Department of Urban and Resources Sciences Nanjing University Nanjing 210093 P. R. China Department of Geography Jiangxi Normal University Nanchang 330027 P. R. China

This paper delineates the images of Jiangxi Province as tourist destination perceived by about 2000 sample visitors at Lushan Mountain and other 3 famous resorts (Jinggangshan Mountains, Longhushan Mountain, and Sanqingshan Mountain), with a result that the most common image is the famous scenic mountain image with partial attribute of image of religious culture destination. In order to reveal the similarities and dissimilarities of images among the four destinations, a correspondence analysis on 16 image attributes was employed. The results indicate that the tourists’ images on Longhushan Mountain, Sanqingshan Mountain and Lushan Mountain are very similar: having a lot of good tourist sites, famous mountain scenery, being close to nature and having good guide service, and others, but religious culture and good shopping facilities having not made deep impression on tourist, while Jinggangshan Mountains is famous for its red culture. The correspondence analysis visualizes the strengths and weaknesses of the destinations, which is useful for market positioning among the competitive places. Finally, some marketing suggestions for the four destinations were provided.

关键词： tourist destination image cognitive attribute evaluative attribute correspondence analysis

Derivation and analysis on the analytical structure of interval type-2 fuzzy controller with two nonlinear fuzzy sets for each input variable

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Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 587-602页

作者： Bin-bin LEI Xue-chao duan Hong bao Qian XU MOE Key Laboratory of Electronic Equipment Structure Design Xidian University Xinjiang Observatory National Astronomical ObservatoriesChinese Academy of Sciences

Type-2 fuzzy controllers have been mostly viewed as black-box function generators. Revealing the analytical structure of any type-2 fuzzy controller is important as it will deepen our understanding of how and why a type-2 fuzzy controller functions and lay a foundation for more rigorous system analysis and design. In this study, we derive and analyze the analytical structure of an interval type-2 fuzzy controller that uses the following identical elements: two nonlinear interval type-2 input fuzzy sets for each variable, four interval type-2 singleton output fuzzy sets, a Zadeh AND operator, and the Karnik-Mendel type reducer. Through dividing the input space of the interval type-2 fuzzy controller into 15 partitions, the input-output relationship for each local region is derived. Our derivation shows explicitly that the controller is approximately equivalent to a nonlinear proportional integral or proportional differential controller with variable gains. Furthermore, by comparing with the analytical structure of its type-1 counterpart, potential advantages of the interval type-2 fuzzy controller are analyzed. Finally, the reliability of the analysis results and the effectiveness of the interval type-2 fuzzy controller are verified by a simulation and an experiment.

关键词： Interval type-2 fuzzy controller Analytical structure Karnik-Mendel type reducer