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Phyton-International Journal of Experimental Botany 2024年第3期93卷 627-640页

作者： Haoxue Wu Xiaohan Zhang Xiaoyu Chen Kang Li Aixia Xu Zhen Huang jungang dong Chengyu Yu College of Agronomy Northwest A&F UniversityYangling712100China

Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus *** is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil *** this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype *** expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and *** three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and *** A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were *** proﬁle of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous *** mutations in BnFAD3 in the high-ALA accessions are reported for theﬁrst *** identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes.

关键词： Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation

MORPHOLOGY AND ELEMENTAL COMPOSITION OF DUSTFALL PARTICLES INSIDE EMPEROR QIN'S TERRA-COTTA WARRIORS AND HORSES MUSEUM

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China Particuology 2006年第6期4卷 346-351页

作者： Tafeng Hu Xuxiang Li jungang dong Bo Rong Zhenxing Shen Junji Cao Shun-Cheng Lee Judith C. Chow John G. Watson Department of Environmental Science and Engineering Xi'an Jiaotong University Xi'an 710049 China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Emperor Qin's Terra-cotta Warriors and Horses Museum Xi'an 710054 China Research Center of Urban Environmental Technology and Management Department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China Division of Atmospheric Sciences Desert Research Institute Nevada System of Higher Education Reno NV USA

Indoor dusffall samples were collected in Pit 1 and Pit 2 of Emperor Qin＇s Terra-cotta Warriors and Horses Museum in Xi＇an, Shaanxi Province, China. The morphological and elemental analysis for long-term （〉10 years） and short-term （～0.5 year） dusffall particles and lacquer pieces on the faces of partly assembled warriors were performed with scanning electron microscopy with energy dispersive X-ray spectrometer （SEM/EDX）. The results showed that the majority of dusffall samples appeared to be composed of mineral dust particles, fly ash, and biological particles with different elemental compositions. Most of the mineral particles had irregular shapes with smooth edges. Small floccules of calcium sulfate were more frequently observed in long-term dusffall samples than in short-term samples, implying a progressive chemical reaction between continuous dusffall particles and atmospheric sulfur dioxide. Crystals of calcium sulfate were also found near pits on both inner and outer surfaces of lacquer pieces, revealing an acid chemical reaction between sulfur dioxide and lacquer material as the cause of the formation of erosion pits and cracks on surface of lacquer pieces.

关键词： indoor dusffall morphology elemental composition SEM/EDX

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高精度光离子化传感器的设计

红外与激光工程 2020年第8期49卷 240-247页

作者：王晋郝现伟董钧港熊继军洪应平中北大学仪器科学与动态测试教育部重点实验室山西太原030051 北京宇航系统工程研究所北京100171 北京首都航天机械有限公司北京100076

针对当前国产光离子气体传感器因精度较小、成本较高而一直无法广泛应用的技术难点问题,提出了一种通过改进结构将射频紫外灯驱动模块和微弱电流检测模块分离的方法。基于光离子化和抗电磁干扰的机理,深入探讨了传感机制和减弱噪声的方... 详细信息

针对当前国产光离子气体传感器因精度较小、成本较高而一直无法广泛应用的技术难点问题,提出了一种通过改进结构将射频紫外灯驱动模块和微弱电流检测模块分离的方法。基于光离子化和抗电磁干扰的机理,深入探讨了传感机制和减弱噪声的方法,设计研制电源模块、紫外灯驱动模块和微弱电流检测模块等解调电路模块。设计特殊的外壳结构,使之在屏蔽外界干扰的同时,也降低了高压交流电给微弱电流检测模块带来的噪声干扰,进而提高了传感器的测试精度。构建了整体传感器的测试与标定系统。理论与实验结果表明:该传感器线性度良好,重复性为1.8%,在室温下工作稳定,可以应用到环境测量中。同时,所设计的传感器因其体积小、灵敏度高和响应快等优点,为其使用的便捷性和测量的实时性提供了可靠的解决方案。

关键词：光离子化解调电路电磁干扰降噪

一种分布式电源的自适应虚拟同步控制策略研究

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电气传动 2019年第7期49卷 78-81,89页

作者：董军刚王丽荣河北软件职业技术学院智能工程系河北保定071003 保定天威保变电气股份有限公司河北保定071003

分布式发电是未来电力可持续使用的重要方式之一。但是,分布式电源的大量接入降低了电网的整体惯性,从而影响到系统的动态响应特性。采用虚拟同步控制方法,可以使得分布式电源具有传统同步发电机的特性,且其惯性大小可在一定范围内调整... 详细信息

分布式发电是未来电力可持续使用的重要方式之一。但是,分布式电源的大量接入降低了电网的整体惯性,从而影响到系统的动态响应特性。采用虚拟同步控制方法,可以使得分布式电源具有传统同步发电机的特性,且其惯性大小可在一定范围内调整是一重要优势。研究了已有的虚拟同步控制方法,分析了系统惯性与频率变化率之间的关系,提出了一种可根据频率变化率自适应改变惯性时间常数的虚拟同步发电机控制策略。最后,通过搭建的微电网实验平台,验证了所提控制方法对弱电网系统的良好支持作用。

关键词：分布式电源微电网虚拟同步发电机自适应控制频率控制

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang GUO Wenqing YANG Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： Chi Ma Dianbiao dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Decision and Coordination in a Closed-Loop Supply Chain with Product Recycling Under Different Low-Carbon Regulations

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Journal of the Operations Research Society of China 2024年第3期12卷 695-728页

作者： Qian-dong dong Hai-Wen Xu School of Management and Engineering Nanjing UniversityNanjing210093JiangsuChina School of Science Civil Aviation Flight University of ChinaGuanghan618307SichuanChina

The implementation of recycling activity is of great significance to closed-loop supply chain ***’environmental awareness and governmental subsidy are considered in the two-echelon closed-loop supply *** types of decision-making structures are proposed under different carbon emission *** subsidy sharing mechanism is designed to resolve the channel members’conflict caused by double *** paper provides insight into the effect of environmental awareness and government subsidy under different low-carbon regulations on the supply chain benefit and social welfare via the game *** analysis results display that the government subsidy and subsidy sharing mechanism are profitably beneficial to the whole supply chain and social ***,a noteworthy result reveals that social welfare is not always directly proportional to consumers’environmental *** welfare decreases slightly with the increase in consumers’environmental awareness when consumers’environmental awareness is ***,social welfare will be significantly improved when consumers’environmental awareness increases beyond a certain threshold.

关键词： Closed-loop supply chain Recycling Coordination Social welfare Game theory Carbon emissions

Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 43-53页

作者： dong Ma Qinhui Wang State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by ***,the PG decomposition temperature remains high and the product yield remains *** adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be ***,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic ***,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same *** effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting ***,the reaction mechanism is *** is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition *** example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) *** process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

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Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： dong ZHAO Wenjing REN School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression

Modeling urban scale human mobility through big data analysis and machinelearning

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Building Simulation 2024年第1期17卷 3-21页

作者： Yapan Liu Bing dong Department of Mechanical&Aerospace Engineering Syracuse University263 Link HallSyracuseNY 13244USA

In the United States,the buildings sector consumes about 76%of electricity use and 40% of all primary energy use and associated greenhouse gas *** behavior has drawn increasing research interests due to its impacts on the building energy ***,occupant behavior study at urban scale remains a challenge,and very limited studies have been *** an effort to couple big data analysis with human mobility modeling,this study has explored urban scale human mobility utilizing three months Global Positioning System(GPS)data of 93,o00 users at Phoenix Metropolitan *** research extracted stay points from raw data,and identified users'home,work,and other locations by Density-Based Spatial Clustering ***,daily mobility patterns were constructed using different types of *** propose a novel approach to predict urban scale daily human mobility patterns with 12-hour prediction horizon,using Long Short-Term Memory(LSTM)neural network *** shows the developed models achieved around 85%average accuracy and about 86%mean *** developed models can be further applied to analyze urban scale occupant behavior,building energy demand and flexibility,and contributed to urban planning.

关键词： urban human mobility big data analysis urban scale occupant behavior recurrent neural networks