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Structural mass prediction in conceptual design of blended-wing-body aircraft

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Chinese Journal of Aeronautics 2019年第11期32卷 2455-2465页

作者： Wensheng zhu Zhouwei fan Xiongqing YU College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The Blended-Wing-Body(BWB) is an unconventional configuration of aircraft and considered as a potential configuration for future commercial aircraft. One of the difficulties in conceptual design of a BWB aircraft is structural mass prediction due to its unique structural feature. This paper presents a structural mass prediction method for conceptual design of BWB aircraft using a structure analysis and optimization method combined with empirical calibrations. The total BWB structural mass is divided into the ideal load-carrying structural mass, non-ideal mass, and secondary structural mass. Structural finite element analysis and optimization are used to predict the ideal primary structural mass, while the non-ideal mass and secondary structural mass are estimated by empirical methods. A BWB commercial aircraft is used to demonstrate the procedure of the BWB structural mass prediction method. The predicted mass of structural components of the BWB aircraft is presented, and the ratios of the structural component mass to the Maximum TakeOff Mass(MTOM) are discussed. It is found that the ratio of the fuselage mass to the MTOM for the BWB aircraft is much higher than that for a conventional commercial aircraft, and the ratio of the wing mass to the MTOM for the BWB aircraft is slightly lower than that for a conventional aircraft.

关键词： Aircraft conceptual design Blended-Wing-Body Finite element method Mass prediction Structural optimization

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溴乙烯在外电场中的解离性质研究

原子与分子物理学报 2025年第4期42卷 20-26页

作者：周华森韩博元努尔比耶·艾则孜章吴熠朱奕虹刘玉柱南京信息工程大学江苏省大气海洋光电探测重点实验室南京210044 江苏省大气环境与装备技术协同创新中心南京210044

溴乙烯具有极高的毒性,它不仅会污染环境,还会损害人类的身心健康.因此,研究它的分子结构及其解离方式,不仅具有重要的科学意义,而且也具有极高的社会意义.本文采用密度泛函理论(DFT),以B3LYP/6-31G++(d,p)基组,深入探索溴乙烯分子在0 V... 详细信息

溴乙烯具有极高的毒性,它不仅会污染环境,还会损害人类的身心健康.因此,研究它的分子结构及其解离方式,不仅具有重要的科学意义,而且也具有极高的社会意义.本文采用密度泛函理论(DFT),以B3LYP/6-31G++(d,p)基组,深入探索溴乙烯分子在0 V·nm^(-1)~80 V·nm^(-1)外电场的影响下,其分子结构和解离特性.通过计算,随着外电场的增强:分子总能量和碳碳双键(C=C)的键长减小,碳溴键(C-Br)的键长和偶极矩增大.能隙E_(G)先增大后减小,分子结构稳定性降低.红外光谱主要产生了6个特征吸收峰,且普遍存在红移现象.分子解离特性表现为:当外部电场强度升高时,势垒会显著减弱,直至达到154.26 V·nm^(-1)时,势垒就会完全消除,溴乙烯分子的解离能相应减弱,这表明,当外部电场强度升高时,溴乙烯分子会发生逐步的分解.因此,这一结论可以为进一步探讨溴乙烯分子和其相关的化合物的解离研究提供依据.

关键词：溴乙烯红外光谱外电场解离势能面降解

Resolving a nearly 90-year-old enigma:The rare Fagus chienii is conspecific with *** based on molecular and morphological evidence

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Plant Diversity 2023年第5期45卷 544-551页

作者： Dan-Qi Li Lu Jiang Hua Liang Da-Hai zhu Deng-Mei fan yi-Xuan Kou yi Yang Zhi-Yong Zhang College of Forestry Jiangxi Agricultural UniversityNanchang 330045China Laboratory of Subtropical Biodiversity Jiangxi Agricultural UniversityNanchang 330045China Lushan Botanical Garden Jiangxi Province and Chinese Academy of SciencesJiujiang 332900China Longxi-Hongkou National Reserve Chengdu 611830China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541004China Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guilin 541006China

Taxonomic uncertainties of rare species often hinder effective prioritization for *** such taxonomic uncertainty is the 90-year-old enigma of Fagus *** was previously only known from the type specimens collected in 1935 in Pingwu County of Sichuan Province,China,and has long been thought to be on the verge of ***,morphological similarities to closely related Fagus species have led many to question the taxonomic status of *** clarify this taxonomic uncertainty,we used the newly collected samples to reconstruct a molecular phylogeny of Chinese Fagus species against the phylogenetic backbone of the whole genus using seven nuclear *** addition,we examined nine morphological characters to determine whether *** is morphologically distinct from its putatively closest relatives(***,***,and ***).Both morphological and phylogenetic analyses indicated that *** is conspecific with *** recommended that *** should not be treated as a separate species in conservation ***,conservation strategies such as in situ protection and ex situ germplasm preservation should be adopted to prevent the peculiar“***”population from extinction.

关键词： Conspecific Fagus chienii F.hayatae Phylogenetics Morphology Conservation

Improvement of the Bayesian neural network to study the photoneutron yield cross sections

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Nuclear Science and Techniques 2022年第11期33卷 1-9页

作者： Yong-yi Li fan Zhang Jun Su Department of Computing Changzhi UniversityChangzhi 046011China Department of Physics Changzhi UniversityChangzhi 046011China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

This work is an attempt to improve the Bayesian neural network (BNN) for studying photoneutron yield cross sections as a function of the charge number Z, mass number A, and incident energy ε. The BNN was improved in terms of three aspects:numerical parameters, input layer, and network structure. First, by minimizing the deviations between the predictions and data, the numerical parameters, including the hidden layer number, hidden node number, and activation function, were selected. It was found that the BNN with three hidden layers, 10 hidden nodes, and sigmoid activation function provided the smallest deviations. Second, based on known knowledge,such as the isospin dependence and shape effect, the optimal ground-state properties were selected as input neurons. Third, the Lorentzian function was applied to map the hidden nodes to the output cross sections, and the empirical formula of the Lorentzian parameters was applied to link some of the input nodes to the output cross sections. It was found that the last two aspects improved the predictions and avoided overfitting, especially for the axially deformed nucleus.

关键词： Bayesian neural network Photoneutron cross sections Giant dipole resonance

Fibrous MXene Aerogels with Tunable Pore of Contaminated Seawater

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Nano-Micro Letters 2023年第5期15卷 298-312页

作者： fan Wu Siyu Qiang Xiao-Dong zhu Wenling Jiao Lifang Liu Jianyong Yu yi-Tao Liu Bin Ding Innovation Center for Textile Science and Technology College of TextilesDonghua UniversityShanghai 201620People’s Republic of China State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science&TechnologyQingdao 266042People’s Republic of China

The seawater desalination based on solardriven interfacial evaporation has emerged as a promising technique to alleviate the global crisis on freshwater ***,achieving high desalination performance on actual,oil-contaminated seawater remains a critical challenge,because the transport channels and evaporation interfaces of the current solar evaporators are easily blocked by the oil slicks,resulting in undermined evaporation rate and conversion ***,we propose a facile strategy for fabricating a modularized solar evaporator based on flexible MXene aerogels with arbitrarily tunable,highly ordered cellular/lamellar pore structures for high-efficiency oil interception and *** core design is the creation of 1D fibrous MXenes with sufficiently large aspect ratios,whose superior flexibility and plentiful link forms lay the basis for controllable 3D assembly into more complicated pore *** cellular pore structure is responsible for effective contaminants rejection due to the multi-sieving effect achieved by the omnipresent,isotropic wall apertures together with underwater superhydrophobicity,while the lamellar pore structure is favorable for rapid evaporation due to the presence of continuous,large-area evaporation *** modularized solar evaporator delivers the best evaporation rate(1.48 kg m-2h-1)and conversion efficiency(92.08%)among all MXene-based desalination materials on oil-contaminated seawater.

关键词： Fibrous MXene aerogels Tunable pore structures Modularized solar evaporator Photothermal desalination

Macroscopic–microscopic calculations offission potential surface of uranium isotopes in the three quadratic surfaces parametrization

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Communications in Theoretical Physics 2020年第10期72卷 113-118页

作者： Xin zhu Zhi-Ming Wang Wen-Jie zhu Chun-Lai Zhong yi-Mo Zhang Long-Yong Liao Tie-Shuan fan State Key Laboratory of Nuclear Physics and Technology Institute for Heavy Ion PhysicsSchool of PhysicsPeking UniversityBeijing100871China

Five-dimensional(5D)fission potential energy surfaces(PES)for uranium nuclei are investigated based on the macroscopic–microscopic Lublin–Strasbourg drop model in the threequadratic-surface parametrization,and the heights of static fission barriers are *** and symmetric fission paths are presented on the 5D PES of 236U for different nuclear *** calculated barrier heights,EAand EB,are quite consistent with the experimental data for all even–even nuclei of uranium isotopes,from 230U to 244U.

关键词： potential energy surface uranium nuclei three quadratic surfaces

Built in electric field boosted photocatalytic performance in a ferroelectric layered material SrBi_(2)Ta_(2)O_(9)with oriented facets:Charge separation and mechanism insights

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Journal of Materials Science & Technology 2022年第28期123卷 222-233页

作者： Biru Liao Xiaomin Liao Huiyuan Xie Yuanchu Qin yi zhu Yang Yu Sen Hou Yuanming Zhang Xiaoyun fan College of Chemistry and Materials Science Jinan UniversityGuangzhou 510632China Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 510632China Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications Jinan UniversityGuangzhou 510632China

Antibiotics have received increasing attention due to their potential adverse effects on aquatic life and human *** to efficiently degrade them into harmless substances is a challenging *** materials with a built-in electric field can offer a strong separation ability for the photoinducedcharge pairs and are now found to be used as ***,a series of different morphologies of SrBi_(2)Ta_(2)O_(9)ferroelectric photocatalysts with high antibiotic degradation efficiency have been successfully synthesized through a molten salt *** the addition of KCl,SrBi_(2)Ta_(2)O_(9)(SBTO 3)with exposed(001)facets shows the most excellent photocatalytic activity for decomposing tetracycline(TC)and ciprofloxacin(CIP)under visible light illumination(λ>420 nm).The rate constants of SBTO 3 for TC and CIP degradation are 1.38×10^(–1)and 4.54×10^(–2)min^(–1),which are 18 and 138 times that of the unmodified sample,*** enhancement of photocatalytic performance is mainly attributed to the spontaneous polarization electric field along the[001]direction which provides a strong driven force for the separation of photoinduced *** KPFM results also confirm that the superior photocatalytic activity is consistent with the big large surface potential changes before and after light *** possible degradation pathways and intermediates of TC and CIP were well analyzed by DFT calculation and *** results highlight that morphology control of the ferroelectric materials exhibits enhanced photocatalytic performance for the degradation of the antibiotic.

关键词： SrBi_(2)Ta_(2)O_(9) Morphology Ferroelectric Photocatalysis Antibiotics Built-in electric field

Cooperation Mechanism Design for Integrated Electricity‑Heat Systems with Information Asymmetry

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Journal of Modern Power Systems and Clean Energy 2023年第3期11卷 873-884页

作者： Jizhong zhu Haohao zhu Weiye Zheng Shenglin Li Junwei fan School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China IEEE

Cooperation between electric power networks(EPNs)and district heating networks(DHNs)has been extensively studied under the assumption that all information exchanged is ***,EPNs and DHNs belonging to different entities may result in marketing *** paper proposes a cooperation mechanism for integrated electricity-heat systems(IEHSs)to overcome information ***,a fraud detection method based on multiparametric programming with guaranteed feasibility reveals the authenticity of the ***,all honest entities are selected to form a ***,to maintain operational independence and distribute benefits fairly,Benders decomposition is enhanced to calculate Shapley values in a distributed ***,the cooperative surplus generated by the coalition is allocated according to the marginal contribution of each *** results show that the proposed mechanism stimulates cooperation while achieving Pareto optimality under asymmetric information.

关键词： Information asymmetry integrated electricityheat system Benders decomposition fraud detection Shapley value

A NON-LINEAR MODEL FOR ESTIMATING THE COST OF ACHIEVING EMISSION REDUCTION TARGETS:THE CASE OF THE U.S.,CHINA AND INDIA

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Journal of Systems Science and Systems Engineering 2012年第3期21卷 297-315页

作者： Lei zhu Xiao-Bing ZHANG ying fan Center for Energy & Environmental Policy Research Institute of Policy and Management Chinese Academy of Sciences Beijing 100190 China Department of Economics University of Gothenburg SE 40530 G teborg Sweden

With the world talking about climate change, the United States （U.S.）, China and India have announced their carbon emission reduction targets. For these three countries to achieve their targets, significant questions arise, shch as what will be the annual emission reduction efforts to achieve those targets, how much it would cost and what would be the economic effects. This paper puts the carbon intensity reduction targets of China and India together with the absolute emission reduction target of the U.S. into the same non-linear model to quantitatively study the optimal emission control strategies and associated total cost for achieving those targets by the year 2020, and estimate and compare the minimized total costs of the three countries to reach their targets. Our results show that the total cost for the U.S. to achieve its emission reduction target is greater than those of China and India in terms of absolute amount. However, in terms of proportion of total cost to GDP, China and India＇s ratios are significantly greater than that of the U.S., indicating that for the developing countries such as China and India, the achievement of emission reduction targets needs relatively greater effort.

关键词： Emission reduction cost analysis emission reduction strategy optimization model