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How to Deal with the Trade-off between Development and Decarbonization for Rural Logistics in China?Evidence from Jiangsu

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Journal of Systems Science and Systems Engineering 2023年第6期32卷 656-686页

作者： Xiaoyu Bian jing xu School of Economics and Management Jiangsu University of Science and TechnologyZhenjiang212013China Business School Yangzhou UniversityYangzhou225009China

Rural logistics faces a dilemma between development and high carbon emissions in China.We assess the tension between rural logistics development and carbon emissions from the perspective of policy guidance by modeling a rural logistics system using Jiangsu’s data.We simulate the development trend of Jiangsu rural logistics under carbon abatement policies from 2021–2030,with a focus on promoting its development while simultaneously reducing carbon emissions at a minimal cost.The findings show that rural logistics will move towards high carbon emissions without a carbon abatement policy,while the huge tax pressure of carbon reduction policies reduces the profitability of rural logistics,leading to a trade-off between development and decarbonization.From the perspective of implementation timing and manner of carbon abatement policies implementation,we propose a pathway for securing the profitability of rural logistics and resolving the trade-off.

关键词： Rural logistics carbon emissions policy guidance decarbonization development trade-off

Challenges and prospects for room temperature solid-state sodiumsulfur batteries

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Nano Research 2024年第3期17卷 1402-1426页

作者： Yashuang Qiu jing xu Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China

Room temperature sodium-sulfur(Na-S)batteries,known for their high energy density and low cost,are one of the most promising next-generation energy storage systems.However,the polysulfide shuttling and uncontrollable Na dendrite growth as well as safety issues caused by the use of organic liquid electrolytes in Na-S cells,have severely hindered their commercialization.Solid-state electrolytes instead of liquid electrolytes are considered to be the most direct and effective solution to solve the above problems.However,its practical application is still greatly challenged due to the poor interfacial compatibility between the all-solid-state electrolytes and the anode/cathode,ionic conductivity,and the shuttle effect caused by the presence of liquid phase in the quasi-solid-state electrolytes.This paper presents a comprehensive review of solid-state Na-S batteries from the perspective of regulating interfacial compatibility and improving ionic conductivity as well as suppressing polysulfide shuttle.According to different components,solid-state electrolytes were divided into five categories:solid inorganic electrolytes,solid polymer electrolytes,polymer/inorganic solid hybrid electrolytes,gel polymer electrolytes,and liquid–solid inorganic hybrid electrolytes.Finally,the prospect of developing high performance solid-state electrolytes to improve the cycling stability of room temperature Na-S cells is envisaged.

关键词： sodium-sulfur batteries solid-state electrolytes ionic conductivity polysulfide shuttling interfacial compatibility

Total synthesis of a putative yuzurimine-type Daphniphyllum alkaloid C_(14)–epi-deoxycalyciphylline H

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Chinese Chemical Letters 2024年第4期35卷 336-339页

作者： jingping Hu jing xu Shenzhen Grubbs Institute and Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Southern University of Science and TechnologyShenzhen 518055China

One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. Key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.

关键词： Total synthesis Daphniphyllum alkaloids Yuzurimine-type alkaloids Prins reaction Enyne cycloisomerization

Can You Feel the Love Tonight: A Dipeptidergic Circuit for Pleasant Touch

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Neuroscience Bulletin 2022年第8期38卷 966-968页

作者： jing-jing Yan Wen Zhang Xiao-Hong xu Institute of Neuroscience State Key Laboratory of NeuroscienceCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai200031China

Soft and gentle touches such as the maternal caressing of infants foster a sense of well-being,promote social bonding,and have long-lasting impacts on the brain and behaviors.Dr.Xiang Yu's group recently identified a dipeptidergic excitatory circuit,from tachykinin 1(Tacl)-expressing neurons in the ventrolateral periaqueductal gray(/vIPAG)to oxytocin neurons in the paraventricular hypothalamus(PVH),that mediates the enduring effects of gentle touch on social behaviors.

关键词： peptidergic gentle hypothalamus

Fast algorithms for singular value decomposition and the inverse of nearly low-rank matrices

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National Science Review 2023年第6期10卷 24-27页

作者： Chen xu Weiwei xu Kaili jing Department of Mathematics and Statistics University of Ottawa School of Mathematics and Statistics Xi'an Jiao Tong University School of Mathematics and Statistics Nanjing University of Information Science and Technology

PROBLEM Matrix computation is a fundamental task in science and engineering;it is recognized as one of the seven computational’giants’of massive data analysis [1],analogous to the seven’dwarfs’in highperformance computing.In recent years,as the scale of datasets rapidly grows,analysts and engineers frequently need to deal with big matrices with a nearly lowrank structure.The big size of a matrix brings great numerical hurdles to matrix computation.In this work,we focus on two typical tasks in matrix computation:singular value decomposition (SVD) and matrix inverse on nearly low-rank matrices that are potentially of big sizes.

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Vehicle and pedestrian detection method based on improved YOLOv4-tiny

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Optoelectronics Letters 2023年第10期19卷 623-628页

作者： LI jing xu Zhengjun xu Liang School of Computer Science and Engineering Tianjin University of TechnologyTianjin300384China School of Electrical Engineering and Automation Tianjin University of TechnologyTianjin300384China

Aiming at the problem of low detection accuracy of vehicle and pedestrian detection models,this paper proposes an improved you only look once v4(YOLOv4)-tiny vehicle and pedestrian target detection algorithm.Convolutional block attention module(CBAM)is introduced into cross stage partial Darknet-53(CSPDarknet53)-tiny module to enhance feature extraction capabilities.In addition,the cross stage partial dense block layer(CSP-DBL)module is used to replace the original simple convolutional module superposition,which compensates for the high-resolution characteristic information and further improves the detection accuracy of the network.Finally,the test results on the BDD100K traffic dataset show that the mean average precision(mAP)value of the final network of the proposed method is 88.74%,and the detection speed reaches 63 frames per second(FPS),which improves the detection accuracy of the network and meets the real-time detection speed.

关键词： replace network method

Introducing a drought index to a crop model can help to reduce the gap between the simulated and statistical yield

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Atmospheric and Oceanic Science Letters 2018年第4期11卷 307-313页

作者： WANG Guo-Cheng ZHANG Qing xu jing-jing LAPC Institute of Atmospheric Physics Chinese Academy of Sciences

农田作物生产模型是一个用于评估众多环境和人为因子影响下作物产量变化的重要工具。然而,将所有与作物生长相关的环境因子考虑进模型中是不现实的。因此,模型往往会在一些极端环境条件发生时高估作物的产量。在本文中,我们试图将一个... 详细信息

农田作物生产模型是一个用于评估众多环境和人为因子影响下作物产量变化的重要工具。然而,将所有与作物生长相关的环境因子考虑进模型中是不现实的。因此,模型往往会在一些极端环境条件发生时高估作物的产量。在本文中,我们试图将一个干旱指数(SPEI)应用到一个农田生态系统过程模型(Agro-C)。同时,对比了模型是否考虑干旱指数的情况下与统计产量之间的差距;用于对比的统计产量是黄淮海平原各县近20年来的小麦和玉米统计数据。研究结果显示:在干旱发生的年份里,模型确实部分高估了作物产量;而在模型中加入干旱指数,则能够一定程度提高模型模拟干旱年份粮食作物的精度。

关键词： Agro-C model crop yield drought index

Multifractal Characteristics of Intermittent Turbulence in the Urban Canopy Layer

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Atmospheric and Oceanic Science Letters 2015年第2期8卷 72-77页

作者： xu jing-jing HU Fei International Center for Climate and Environment Science (ICCES) Institute of Atmospheric Physics Chinese Academy of Science State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences

The multifractality of energy and thermal dissipation of fully developed intermittent turbulence is investigated in the urban canopy layer under unstable conditions by the singularity spectrum for the fractal dimensions of sets of singularities characterizing multifractals. In order to obtain high-order moment properties of smallscale turbulent dissipation in the inertial range, an ultrasonic anemometer with a high sampling frequency of 100 Hz was used. The authors found that the turbulent signal could be singular everywhere. Moreover, the singular exponents of energy and thermal dissipation rates are most frequently encountered at around 0.2, which is significantly smaller than the singular exponents for a wind tunnel at a moderate Reynolds number. The evidence indicates a higher intermittency of turbulence in the urban canopy layer at a high Reynolds number, which is demonstrated by the data with high temporal resolution. Furthermore, the temperature field is more intermittent than the velocity field. In addition, a large amount of samples could be used for verification of the results.

关键词：多重分形分形特征间歇性冠层城市奇异指数高时间分辨率湍流耗散

On the scaling law of ramp structures in scalar turbulence

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Atmospheric and Oceanic Science Letters 2018年第4期11卷 372-377页

作者： CHEN Dong-Wei HU Fei xu jing-jing State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences

斜坡结构在标量湍流中广泛存在,指标量的浓度随时间缓慢爬升然后突然下降的现象,它表明湍流并非完全随机的。基于北京市325米气象铁塔的湍流观测数据,本文利用小波分析提取了温度、水汽和二氧化碳序列中的斜坡结构,其上升部分线性拟合... 详细信息

斜坡结构在标量湍流中广泛存在,指标量的浓度随时间缓慢爬升然后突然下降的现象,它表明湍流并非完全随机的。基于北京市325米气象铁塔的湍流观测数据,本文利用小波分析提取了温度、水汽和二氧化碳序列中的斜坡结构,其上升部分线性拟合的斜率与持续时间存在明显的标度律,三者幂指数相差不大,而且在下降部分也存在类似的规律。同时将斜坡结构上升部分的最大值按时间顺序排列,发现最大值序列依然存在斜坡结构。这表明标量湍流中斜坡结构是自相似的,小尺度的斜坡结构叠加在大尺度的斜坡结构上。

关键词：标量湍流斜坡结构标度律自相似