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Journal of Forestry Research 2024年第3期35卷 175-188页

作者： niu zhu Jinniu Wang Dongliang Luo Xufeng Wang Cheng Shen Ning Wu Ning Zhang Binghui Tian Aihong Gai Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041People's Republic of China College of Resources and Environmental Sciences Gansu Agricultural UniversityLanzhou 730070People's Republic of China Mangkang Ecological Monitoring Station Tibet Ecological Security Barrier Ecological Monitoring NetworkQamdo 854500People's Republic of China Northwest Institute of Eco Environmental Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China

Evapotranspiration is an important parameter used to characterize the water cycle of *** under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qinghai-Tibet Plateau,an open-path eddy covariance system was set up to monitor the forest from November 2020 to October 2021 in a core area of the Three Parallel Rivers in the Qing-hai-Tibet *** results show that the evapotranspira-tion peaked daily,the maximum occurring between 11:00 and 15:*** factors had significant effects on evapotranspiration,among them,net radiation the greatest(R^(2)=0.487),and relative humidity the least(R^(2)=0.001).The energy flux varied considerably in different seasons and sensible heat flux accounted for the main part of turbulent *** energy balance ratio in the dormant season was less than that in the growing season,and there is an energy imbalance at the site on an annual time scale.

关键词： Evapotranspiration Energy balance Subalpine forest Three Parallel Rivers region Southeast Qinghai-Tibet Plateau

采用两步炭化法和熔盐模板法制备N、S共掺杂煤基硬炭及共储钠性能（英文）

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新型炭材料(中英文) 2024年第2期39卷 297-307页

作者：牛慧祝王海花孙立宇杨晨榕王雨曹瑞杨存国王洁舒珂维陕西科技大学化学与化工学院陕西科技大学西安市先端性能材料与高分子创新团队陕西科技大学陕西省工业化学添加剂重点实验室西安北方惠安化学工业有限公司

硬炭因资源丰富、结构稳定及安全性高等优势，已成为钠离子电池常用阳极材料。其中，煤基衍生硬炭受到了广泛的关注。本工作以长焰煤为碳源，硫脲为氮硫源，NaCl为模板，通过两步炭化工艺和杂原子掺杂相结合的方法合成了N和S共掺杂的煤... 详细信息

硬炭因资源丰富、结构稳定及安全性高等优势，已成为钠离子电池常用阳极材料。其中，煤基衍生硬炭受到了广泛的关注。本工作以长焰煤为碳源，硫脲为氮硫源，NaCl为模板，通过两步炭化工艺和杂原子掺杂相结合的方法合成了N和S共掺杂的煤基硬炭（NSPC1200）。两步炭化过程在调节碳微晶结构和扩大层间距方面发挥了重要的作用。N和S的共掺杂调节了炭材料的电子结构，赋予其更多的活性位点；此外，引入NaCl作为模板有助于孔结构的构建，有利于电极和电解质之间的接触，从而实现Na+和电子的有效传输。在协同作用下，样品NSPC1200表现出优异的储钠能力，在20 mAg-1电流密度下呈现314.2 mAhg-1的可逆容量。即使在100 mAg-1下循环200次，仍保持224.4 mAhg-1的比容量。这项工作成功实现了策略性调整煤基炭材料微观结构的目标，最终获得了具有优异的电化学性能的硬炭阳极。

关键词：硬炭钠离子电池煤衍生炭两步炭化氮硫共掺杂

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柔性材质管线交互式仿真的研究与实现

计算机仿真 2024年第6期41卷 416-422页

作者：朱牛牛丁刚毅闫大鹏北京理工大学计算机学院北京100081

针对目前交互式引擎中柔性材质管线受到外界约束后横截面变形仿真不足的问题,提出了虚拟环境下柔性材质管线的交互式仿真框架。给出了一种适用于基于位置动力学模拟框架的基于约束的柔性材质管线物性建模方法,弥补了现有柔性管线仿真横... 详细信息

针对目前交互式引擎中柔性材质管线受到外界约束后横截面变形仿真不足的问题,提出了虚拟环境下柔性材质管线的交互式仿真框架。给出了一种适用于基于位置动力学模拟框架的基于约束的柔性材质管线物性建模方法,弥补了现有柔性管线仿真横截面不发生变形的缺点以及传统有限元方法计算速度慢、边界条件设置复杂的缺点,提高了柔性管线仿真的速度。在仿真引擎的基础上实现了柔性材质管线的交互式仿真系统,并进行了实验验证。结果表明上述系统能够有效模拟柔性管线横截面变形并且实现了交互式实时仿真。

关键词：柔性材质管线仿真框架基于位置动力学实时仿真

黄土高原典型丘陵沟壑区的滑坡灾损土地生态修复研究进展

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草业科学 2024年第6期41卷 1306-1323页

作者：朱牛刘桦王金牛宿星石凝罗栋梁盖艾鸿甘肃农业大学资源与环境学院甘肃兰州730070 中国科学院成都生物研究所四川成都610041 西藏生态安全屏障监测站网芒康生物多样性与生态站西藏昌都854500 甘肃省科学院地质自然灾害防治研究所甘肃兰州730000 中国科学院西北生态环境资源研究院甘肃兰州730000

我国是地质灾害频发的国家,滑坡是地质灾害的主要类型之一。陇中黄土丘陵区地处黄土高原西段的黄河流域上游,一直以来是滑坡事件的高发区,因其突发性造成的次生灾害给当地人民生命财产安全带来了较大隐患。近年来随着社会防治力度与投... 详细信息

我国是地质灾害频发的国家,滑坡是地质灾害的主要类型之一。陇中黄土丘陵区地处黄土高原西段的黄河流域上游,一直以来是滑坡事件的高发区,因其突发性造成的次生灾害给当地人民生命财产安全带来了较大隐患。近年来随着社会防治力度与投入加大,该区域有关滑坡的理论研究和技术修复手段有了较为全面的提升,特别在生态修复研究与实践领域取得了一定的进展。但是,该区域现有的针对性研究方法与灾损土地的修复手段仍然存在一定的局限性与不足。因此,本文就陇中黄土丘陵区滑坡的影响因素和现有修复模式进行综述,首先采用地理信息系统手段图示研究区域的环境概况,进而运用文献计量学的方法系统概括该领域的研究热点内容,并就目前滑坡灾损土地修复的不足之处提出相关解决办法,以期能够全面阐述滑坡灾损治理的必要性,为未来滑坡治理梳理潜在的研究方向,促进滑坡治理更好地发展。

关键词：陇中地区黄土丘陵地质灾害修复模式人类活动文献计量分析

The Exchange Attack and the Mixture Differential Attack Revisited: From the Perspective of Automatic Evaluation

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Chinese Journal of Electronics 2024年第1期33卷 19-29页

作者： Kexin QIAO Zhiyu ZHANG Zhongfeng niu Liehuang zhu School of Cyberspace Science and Technology Beijing Institute of Technology State Key Laboratory of Cryptology Institute of Information Engineering Chinese Academy of Sciences School of Cryptography University of Chinese Academy of Sciences

Recent results show that the differential properties within quadruples boom as a new inspiration in cryptanalysis of Advanced Encryption Standard(AES)-like constructions. These methods include the exchange attack proposed in Asiacrypt’19, the mixture differential attack proposed in To SC’18, etc., where the essential properties are obtained by manually scrutinizing the structures of the AES-like constructions. This paper presents a novel framework and an automatic tool based on mixed integer linear programming to search for mixture differential distinguishers for general constructions. This framework considers what equality patterns among quadruples can make a distinguisher and traces how the patterns propagate through cipher components with accurate probability *** this tool, a 5-round AES distinguishing attack with lower complexity and more 6-round distinguishing attacks in the chosen plaintext scenarios are deduced. We prove that no exchange-type or mixture differential distinguisher exists for 7 and above rounds AES if the details of the Sbox and Mix Columns matrix are not taken into account.

关键词： Ciphers Estimation Encryption Mixed integer linear programming Complexity theory Standards

UAV-assisted cooperative offloading energy efficiency system for mobile edge computing

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Digital Communications and Networks 2024年第1期10卷 16-24页

作者： Xue-Yong Yu Wen-Jin niu Ye zhu Hong-Bo zhu Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing210003China Engineering Research Centerof Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjng Universityof Posts and Telecommunications Nanjing210003China

Reliable communication and intensive computing power cannot be provided effectively by temporary hot spots in disaster areas and complex terrain ground *** this has greatly developed the application and integration of UAV and Mobile Edge Computing(MEC)to the Internet of Things(loT).However,problems such as multi-user and huge data flow in large areas,which contradict the reality that a single UAV is constrained by limited computing power,still *** to allowing UAV collaboration to accomplish complex tasks,cooperative task offloading between multiple UAVs must meet the interdependence of tasks and realize parallel processing,which reduces the computing power consumption and endurance pressure of *** the computing requirements of the user terminal,delay constraint of a computing task,energy constraint,and safe distance of UAV,we constructed a UAV-Assisted cooperative offloading energy efficiency system for mobile edge computing to minimize user terminal energy ***,the resulting optimization problem is originally nonconvex and thus,difficult to solve *** tackle this problem,we developed an energy efficiency optimization algorithm using Block Coordinate Descent(BCD)that decomposes the problem into three convex ***,we jointly optimized the number of local computing tasks,number of computing offloaded tasks,trajectories of UAV,and offloading matching relationship between multi-UAVs and multiuser *** results show that the proposed approach is suitable for different channel conditions and significantly saves the user terminal energy consumption compared with other benchmark schemes.

关键词： Computation offloading Internet of things(IoT) Mobile edge computing(MEC) Block coordinate descent(BCD)

Machine Learning-Based Research on Tensile Strength of SiC-Reinforced Magnesium Matrix Composites via Stir Casting

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 453-466页

作者： Zhihong zhu Wenhang Ning Xuanyang niu Yuhong Zhao Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

SiC is the most common reinforcement in magnesium matrix composites,and the tensile strength of SiC-reinforced magnesium matrix composites is closely related to the distribution of *** a uniform distribution of SiC requires fine control over the parameters of SiC and the processing and preparation ***,due to the numerous adjustable parameters,using traditional experimental methods requires a considerable amount of experimentation to obtain a uniformly distributed composite ***,this study adopts a machine learning approach to explore the tensile strength of SiC-reinforced magnesium matrix composites in the mechanical stirring casting *** analyzing the influence of SiC parameters and processing parameters on composite material performance,we have established an effective predictive ***,six different machine learning regression models have been developed to predict the tensile strength of SiC-reinforced magnesium matrix *** validation and comparison,our models demonstrate good accuracy and reliability in predicting the tensile strength of the composite *** research findings indicate that hot extrusion treatment,SiC content,and stirring time have a significant impact on the tensile strength.

关键词： Machine learning Stirring casting Magnesium matrix composite Tensile strength

Sliding behaviors of the trapezoidal roof rock block under a lateral dynamic disturbance

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 741-760页

作者： Feng Dai Wancheng zhu Min Ren Shunchuan Wu Leilei niu Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming650093China Center for Rock Instability and Seismicity Research Department of Mining EngineeringSchool of Resource and Civil EngineeringNortheastern UniversityShenyang110819China

The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A series of laboratory tests,numerical simulations and theoretical analyses were carried out in this study to disclose the sliding mechanism of roof rock blocks under lateral ***,the experiments on trapezoidal key block under various clamping loads and disturbance were conducted,followed by numerical simulations using the fast Lagrangian analysis of continua(FLAC3D).Then,based on the conventional wave propagation model and the classical shear-slip constitutive model,a theoretical model was proposed to capture the relative displacement between blocks and the sliding displacement of the key *** results indicate that the sliding displacement of the key block increased linearly with the disturbance energy and decreased exponentially with the clamping load when the key block was disturbed to slide(without instability).Meanwhile,when the key block was disturbed to fall,two types of instability process may appear as immediate type or delayed *** addition,the propagation of stress waves in the block system exhibited obvious low-velocity and lowfrequency characteristics,resulting in the friction reduction effect appearing at the contact interface,which is the essential reason for the sliding of rock *** results can be applied to practical underground engineering and provide valuable guidance for the early detection and prevention of rockfalling disasters.

关键词： Lateral dynamic disturbance Trapezoidal rock block system Low-velocity and low-frequency wave Friction reduction effect Instability mode

Breeding exceptionally fragrant soybeans for soy milk with strong aroma

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Journal of Integrative Plant Biology 2024年第4期66卷 642-644页

作者： Hongtao Xie Minglei Song Xuesong Cao Qingfeng niu Jianhua zhu Shasha Li Xin Wang Xiaomu niu Jian-Kang zhu Bellagen Biotechnology Co.Ltd. Jinan 250000China Institute of Advanced Biotechnology and School of Life Sciences Southern University of Science and TechnologyShenzhen 518055China School of Life Sciences Anhui Agricultural UniversityHefei 230036China Shandong Normal University Jinan 250000China

Soybean(Glycine max(L.)Merr.)is a major source of vegetable protein and oil in human diet and animal *** seeds have been extensively used in various food products and *** quality,particularly the aroma,affects cooking and eating,and ultimately influences consumer *** milk is particularly popular in China and has been gaining popularity in many other countries in the world.

关键词： exceptional soybean cooking

Melittin enhanced intracellular trehalose with synergistic membrane stabilization of macromolecular protectants for cell cryopreservation

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Science China(Technological Sciences) 2024年第4期67卷 1160-1169页

作者： niu QingJing GAO ShuHui zhu KongYing REN LiXia YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Analysis and Measurement Center Tianjin UniversityTianjin 300072China

Cryopreservation plays an essential role in biobanking and cell therapy,but the physiological toxicity of traditional cryoprotectants such as glycerol and dimethyl sulfoxide(DMSO)has raised safety issues for biomedical ***,a nonreducing disaccharide that accumulates in desiccation-or cold-tolerant organisms,has been considered as a biocompatible ***,a naturally occurring membrane-active cationic peptide,melittin,was utilized to facilitate membraneimpermeable trehalose entry into cells for effective cell ***(ethylene glycol)and poly(vinyl pyrrolidone)were applied as macromolecular protectants to improve the stabilization of cell *** the optimal protocol,the postthaw recovery of human red blood cells in freezing bags at a hematocrit of~50%could achieve 82.9%with favorable cell morphologies and physiological ***,the cryosurvival of L929 fibroblasts reached 84.3%compared to the conventional method using 10%(v/v)*** short,this work by using trehalose and melittin provides a biocompatible solvent-free approach for long-term cryostorage of cells.

关键词： melittin intracellular trehalose membrane stabilization macromolecular protectants cell cryopreservation

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