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Multi-objective layout optimization of a satellite module using the Wang-Landau sampling method with local search

Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 527-542页

作者： Jing-fa LIU Liang HAO Gang LI Yu XUE Zhao-xia LIU Juan HUANG jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science&TechnologyNanjing 210044China School of Computer&Software Nanjing University of Information Science&TechnologyNanjing 210044China School of Mathematics and Statistics Nanjing University of Information Science&TechnologyNanjing 210044China Office of lnformationization Construction and Management Nanjing University of Information Science&TechnologyNanjing 210044China

The layout design of satellite modules is considered to be NP-hard. It is not only a complex coupled system design problem but also a special multi-objective optimization problem. The greatest challenge in solving this problem is that the function to be optimized is characterized by a multitude of local minima separated by high-energy barriers. The Wang-Landau(WL) sampling method, which is an improved Monte Carlo method, has been successfully applied to solve many optimization problems. In this paper we use the WL sampling method to optimize the layout of a satellite module. To accelerate the search for a global optimal layout, local search(LS) based on the gradient method is executed once the Monte-Carlo sweep produces a new layout. By combining the WL sampling algorithm, the LS method, and heuristic layout update strategies, a hybrid method called WL-LS is proposed to obtain a final layout scheme. Furthermore, to improve significantly the efficiency of the algorithm, we propose an accurate and fast computational method for the overlapping depth between two objects(such as two rectangular objects, two circular objects, or a rectangular object and a circular object) embedding each other. The rectangular objects are placed orthogonally. We test two instances using first 51 and then 53 objects. For both instances, the proposed WL-LS algorithm outperforms methods in the literature. Numerical results show that the WL-LS algorithm is an effective method for layout optimization of satellite modules.

关键词：多目标优化问题优化布局局部搜索采样算法卫星舱模块朗道蒙特卡罗方法

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Covalent Assembly of Penicillin Acylase in Mesoporous Silica Based on Macromolecular Crowding Theory

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Chinese Journal of Chemical Engineering 2007年第6期15卷 788-790页

作者：王安明周成王华沈树宝薛建跃欧阳平凯 College of Life science and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 China Department of Chemistry Chaohu College Chaohu 238000 China

改进青霉素 acylase (PA ) 的共有原子价固定，宏分子的拥挤理论被用于它的固定。到硅石的酶的集体比率的影响，以及，有在装配 PA 的活动的 glutaraldehyde 的激活时间，被学习。在中央毛孔，酶的固定上的β - 出租机动三轮车糊精(β -... 详细信息

改进青霉素 acylase (PA ) 的共有原子价固定，宏分子的拥挤理论被用于它的固定。到硅石的酶的集体比率的影响，以及，有在装配 PA 的活动的 glutaraldehyde 的激活时间，被学习。在中央毛孔，酶的固定上的β - 出租机动三轮车糊精(β - CD ) 的效果也被调查。当青霉素 acylase 在中央毛孔 covalently 集合了时，分别地，联合收益和相对活动到达了 99.5% 和 92.3% ，是显著的。这里的结果显示拥挤的那个模仿的大分子能显著地改善 covalently 使不能调动的 PA 的表演。

关键词：酶固定化青霉素酰基转移酶 β-环糊精高分子聚合理论

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冷媒辅助搅拌摩擦处理AZ31B镁合金的显微组织演变及力学性能

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Transactions of Nonferrous Metals Society of China 2023年第6期33卷 1729-1741页

作者：许楠任紫科范越顾帛坤沈骏宋亓宁赵建华包晔峰河海大学机电工程学院常州213022 重庆大学国家镁合金材料工程技术研究中心重庆400044 重庆大学材料科学与工程学院重庆400044

传统搅拌摩擦处理(FSP)后的AZ31B镁合金通常表现出强烈的基面织构,导致其强度和塑性匹配较差。本文作者采用冷媒辅助搅拌摩擦处理对AZ31B镁合金进行加工,研究液态二氧化碳冷却剂对搅拌区热循环、显微组织和力学性能的影响。使用液态二... 详细信息

传统搅拌摩擦处理(FSP)后的AZ31B镁合金通常表现出强烈的基面织构,导致其强度和塑性匹配较差。本文作者采用冷媒辅助搅拌摩擦处理对AZ31B镁合金进行加工,研究液态二氧化碳冷却剂对搅拌区热循环、显微组织和力学性能的影响。使用液态二氧化碳同步冷却法可显著降低搅拌区的峰值温度并提高冷却速度,搅拌区出现具有大量位错和■孪晶的细晶结构。在不连续动态再结晶、连续动态再结晶和孪晶诱导几何动态再结晶的综合作用下,搅拌区发生显著的晶粒细化。拉伸试验中由于位错和■孪晶产生的交互作用,搅拌区的极限抗拉强度和断后伸长率分别达293 MPa和18.6%,表现出良好的强度和塑性匹配。

关键词：镁合金搅拌摩擦处理 Zenner-Hollomon参数再结晶显微组织演变力学性能

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An efficient and coordinated mapping algorithm in virtualized SDN networks

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Frontiers of Information Technology & Electronic Engineering 2016年第7期17卷 701-716页

作者： Shui-qing GONG Jing CHEN Qiao-yan KANG Qing-wei MENG Qing-chao ZHU Si-yi ZHAO College of Information and Navigation Air Force Engineering University

Software-defined networking(SDN) enables the network virtualization through SDN hypervisors to share the underlying physical SDN network among multiple logically isolated virtual SDN networks(v SDNs),each with its own controller.The v SDN embedding,which refers to mapping a number of v SDNs to the same substrate SDN network,is a key problem in the SDN virtualization environment.However,due to the distinctions of the SDN,such as the logically centralized controller and different virtualization technologies,most of the existing embedding algorithms cannot be applied directly to SDN virtualization.In this paper,we consider controller placement and virtual network embedding as a joint vS DN embedding problem,and formulate it into an integer linear programming with objectives of minimizing the embedding cost and the controller-to-switch delay for each v SDN.Moreover,we propose a novel online vS DN embedding algorithm called CO-v SDNE,which consists of a node mapping stage and a link mapping stage.In the node mapping stage,CO-vS DNE maps the controller and the virtual nodes to the substrate nodes on the basis of the controller-to-switch delay and takes into account the subsequent link mapping at the same time.In the link mapping stage,CO-v SDNE adopts the k-shortest path algorithm to map the virtual links.The evaluation results with simulation and Mininet emulation show that the proposed CO-v SDNE not only significantly increases the long-term revenue to the cost ratio and acceptance ratio while guaranteeing low average and maximum controller-to-switch delay,but also achieves good v SDN performance in terms of end-to-end delay and throughput.

关键词： Software-defined networking(SDN) Network virtualization Controller placement Virtual network embedding Coordination

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Sustainable management of campus fallen leaves through low-temperature pyrolysis and application in Pb immobilization

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Journal of Environmental sciences 2024年第5期139卷 281-292页

作者： Rongli Tan Ke Li Yue Sun Xiaoliang Fan Zhengtao Shen Lingyi Tang School of Environment Nanjing UniversityNanjing 210023China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China School of Earth and Engineering sciences Nanjing UniversityNanjing 210023China Department of Earth and Atmospheric sciences University of AlbertaEdmonton T6G 2E3Canada

Realizing campus sustainability requires the environmental-friendly and economical treatment of tremendous fallen leaves.Producing fallen leaf biochar at a low temperature is a candidate approach.In this study,six common types of fallen leaves on the campus were pyrolyzed at 300℃.The obtained biochars were characterized and the adsorption mechanisms of lead(Pb)by the fallen leaf biochars were investigated.The adsorption capacity of leaf biochar for Pb was relatively high,up to 209 mg/g(Yulania denudata leaf biochar).Adsorption of Pb onto active sites was the rate-limiting step for most leaf biochars.But for Platanus leaf biochar,intraparticle diffusion of Pb^(2+)dominated owing to the lowest adsorption capacity.However,the highest exchangeable Pb fraction(27%)indicated its potential for removing aqueous Pb^(2+).Ginkgo and Prunus cerasifera leaf biochar immobilized Pb by surface complexation and precipitation as lead oxalate.Hence,they were suitable for soil heavy metal remediation.This study shed the light on the sustainable utilization of campus fallen leaves and the application of fallen leaf biochars in heavy metal remediation.

关键词： Fallen leaves Waste management Biochar Lead removal Sorption Circular campus

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Multifunctional MXene/C Aerogels for Enhanced Microwave Absorption and Thermal Insulation

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纳微快报:英文版 2023年第11期15卷 74-89页

作者： Fushuo Wu Peiying Hu Feiyue Hu Zhihua Tian Jingwen Tang Peigen Zhang Long Pan Michel WBarsoum Longzhu Cai ZhengMing Sun School of Materials science and Engineering Southeast UniversityNanjing 211189People’s Republic of China Department of Materials science&Engineering Drexel UniversityPhiladelphiaPA 19104USA The State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096People’s Republic of China

Two-dimensional transition metal carbides and nitrides(MXene)have emerged as promising candidates for microwave absorption(MA)materials.However,they also have some drawbacks,such as poor impedance matching,high self-stacking tendency,and high density.To tackle these challenges,MXene nanosheets were incorporated into polyacrylonitrile(PAN)nanofibers and subsequently assembled into a three-dimensional(3D)network structure through PAN carbonization,yielding MXene/C aerogels.The 3D network effectively extends the path of microcurrent transmission,leading to enhanced conductive loss of electromagnetic(EM)waves.Moreover,the aerogel’s rich pore structure significantly improves the impedance matching while effectively reducing the density of the MXenebased absorbers.EM parameter analysis shows that the MXene/C aerogels exhibit a minimum reflection loss(RL_(min))value of−53.02 dB(f=4.44 GHz,t=3.8 mm),and an effective absorption bandwidth(EAB)of 5.3 GHz(t=2.4 mm,7.44–12.72 GHz).Radar cross-sectional(RCS)simulations were employed to assess the radar stealth effect of the aerogels,revealing that the maximum RCS reduction value of the perfect electric conductor covered by the MXene/C aerogel reaches 12.02 dB m^(2).In addition to the MA performance,the MXene/C aerogel also demonstrates good thermal insulation performance,and a 5-mm-thick aerogel can generate a temperature gradient of over 30℃ at 82℃.This study provides a feasible design approach for creating lightweight,efficient,and multifunctional MXene-based MA materials.

关键词： MXene Microwave absorption Aerogel Radar cross-sectional(RCS)simulation Thermal insulation

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A Modified Model of Ecological Footprint Accounting and Its Application to Cropland in jiangsu,China

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Pedosphere 2008年第2期18卷 154-162页

作者： LIU Qin-Pu LIN Zhen-Shan FENG Nian-Hua LIU Yong-Mei Geographical science College Nanjing Xiaozhuang University Nanjing 210017 （China） Geographical science College Nanjing Normal University Nanjing 210097 （China）

Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and applied to a case study of jiangsu cropland,China.Comparisons between the EF and the EMEF with respect to grain,cotton,and food oil were outlined.Per capita EF and EMEF of cropland were also presented to depict the resources consumption level by comparing the biocapacity(BC)or emergetic biocapacity(EMBC,a new BC calculation by emergy analysis) of the same area.In the meanwhile,the ecological sustainability index(ESI),a new concept initiated by the authors, was established in the modified model to indicate and compare the sustainability of cropland use at different levels and between different regions.The results from conventional EF showed that per capita EF of the cropland has exceeded its per capita BC in jiangsu since 1986.In contrast,based on the EMBC,the per capita EMEF exceeded the per capita EMBC 5 years earlier.The ESIs of jiangsu cropland use were between 0.7 and 0.4 by the conventional method,while the numbers were between 0.7 and 0.3 by the modified one.The fact that the results of the two methods were similar showed that the modified model was reasonable and feasible,although some principles of the EF and EMEF were quite different. Also,according to the realities of jiangsu cropland use,the results from the modified model were more acceptable.

关键词：农田生态学足迹模型江苏土壤

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Design and Application of m-Hydroxybenzyl Alcohols in Regioselective(3+3)Cycloadditions of 2-Indolymethanols

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Chinese Journal of Chemistry 2023年第1期41卷 27-36页

作者： Yi-Cheng Shi Xin-Yu Yan Ping Wu Song Jiang Ran Xu Wei Tan Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhouJiangsu 221116China School of Petrochemical Engineering Changzhou UniversityChangzhouJiangsu 213164China

A new class of m-hydroxybenzyl alcohols has been designed as competent three-carbon building blocks and achieved their applica-tion in 2-indolylmethanol-involved regioselective(3+3)cycloadditions under the catalysis of Br?nsted acids.By this appoach,a series of indole-fused six-membered cycloadducts have been synthesized in overall good yields(up to 98%)with excellent regioselectivity(all>95:5 rr),thus affording a powerful method for the construction of indole-fused six-membered rings.Moreover,a catalytic asymmetric version of this(3+3)cycloaddition has been preliminarily investigated,which revealed the potential of the reaction for constructing chiral indole-fused six-membered rings in an enantioselective manner.This work not only has accomplished the first design of m-hydroxybenzyl alcohols as competent reactants,but also represents the first application of m-hydroxybenzyl alcohols as three-carbon building blocks in cycloadditions.In addition,this work provides a good example for regioselective and C3-nucleophilic(3+3)cycloadditions of 2-indolylmethanols,which will substantially enrich the chemistry of 2-indolylmethanols.

关键词： m-Hydroxybenzyl alcohols 2-lndolymethanols Cycloaddition Regioselectivity Heterocycles

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Molecular insights of nanozymes from design to catalytic mechanism

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science China Chemistry 2023年第5期66卷 1318-1335页

作者： Yuan Xu Zhixin Zhou Nankai Deng Kangchun Fu Caixia Zhu Qing Hong Yanfei Shen Songqin Liu Yuanjian Zhang jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical ResearchSchool of Chemistry and Chemical EngineeringMedical SchoolSoutheast UniversityNanjing 21l189China

Emerging as cost-effective potential alternatives to natural enzymes,nanozymes have attracted increasing interest in broad fields.To exploit the in-depth potential of nanozymes,rational structural engineering and explicit catalytic mechanisms at the molecular scale are required.Recently,impressive progress has been made in mimicking the characteristics of natural enzymes by constructing metal active sites,binding pockets,scaffolds,and delicate allosteric regulation.Ingenious in-depth studies have been conducted with advances in structural characterization and theoretical calculations,unveiling the“black box”of nanozymecatalytic mechanisms.This review introduces the state-of-art synthesis strategies by learning from the natural enzyme counterparts and summarizes the general overview of the nanozyme mechanism with a particular emphasis on the adsorbed intermediates and descriptors that predict the nanozyme activity.The emerging activity assessment methodology that illustrates the relationship between electrochemical oxygen reduction and enzymatic oxygen reduction is discussed with up-to-date advances.Future opportunities and challenges are presented in the end to spark more profound work and attract more researchers from various backgrounds to the flourishing field of nanozymes.

关键词： nanozyme mechanism descriptor free-ROS bound-ROS

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Roles of nanoparticles in arsenic mobility and microbial community composition in arsenic-enriched soils

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Journal of Environmental sciences 2024年第4期138卷 301-311页

作者： Ting Luo Qining Zheng Jie Yu Weihao Liang Yan Sun Guixiang Quan Feng Zhou School of Environmental science and Engineering Yancheng Institute of TechnologyYancheng 224051China jiangsu Provincial Key Laboratory of Coastal Ecology and Pollution Control Yancheng 224051China School ofEnvironment and Civil Engineering Jiangnan UniversityWuxi 214122China

Environmental effects of nano remediation engineering of arsenic(As)pollution need to be considered.In this study,the roles of Fe_(2)O_(3)and TiO_(2)nanoparticles(NPs)on the microbial mediated As mobilization from As contaminated soil were investigated.The addition of Fe_(2)O_(3)and TiO_(2)NPs restrained As(V)release,and stimulated As(Ⅲ)release.As(V)concentration decreased by 94% and 93% after Fe_(2)O_(3)addition,and decreased by 89% and 45% after Ti O_(2)addition compared to the Biotic and Biotic+Acetate(amended with sodium acetate)controls,respectively.The maximum values of As(Ⅲ)were 20.5 and 27.1μg/L at 48 d after Fe_(2)O_(3)and TiO_(2)NPs addition,respectively,and were higher than that in Biotic+Acetate control(12.9μg/L).The released As co-precipitated with Fe in soils in the presence of Fe_(2)O_(3)NPs,but adsorbed on TiO_(2)NPs in the presence of TiO_(2)NPs.Moreover,the addition of NPs amended with sodium acetate as the electron donor clearly promoted As(V)reduction induced by microbes.The NPs addition changed the relative abundance of soil bacterial community,while Proteobacteria(42.8%-70.4%),Planctomycetes(2.6%-14.3%),and Firmicutes(3.5%-25.4%)were the dominant microorganisms in soils.Several potential As/Fe reducing bacteria were related to Pseudomonas,Geobacter,Desulfuromonas,and Thiobacillus.The addition of Fe_(2)O_(3)and TiO_(2)NPs induced to the decrease of arr A gene.The results indicated that the addition of NPs had a negative impact on soil microbial population in a long term.The findings offer a relatively comprehensive assessment of Fe_(2)O_(3)and TiO_(2)NPs effects on As mobilization and soil bacterial communities.

关键词： Fe_(2)O_(3)and TiO_(2)nanoparticles Arsenic reduction Mobilization Functional gene Microbial community

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