检索结果-南通市图书馆

Discrete element modeling and parameter calibration of safflower biomechanical properties

International Journal of Agricultural and Biological Engineering 2024年第2期17卷 37-46页

作者： Zhenguo Zhang Chao Zeng zhenyu xing Peng Xu Quanfeng Guo Ruimeng Shi Yunze Wang College of Mechanical and Electrical Engineering Xinjiang Agricultural UniversityUrumqi 830052China Key Laboratory of Xinjiang Intelligent Agricultural Equipment Xinjiang Agricultural UniversityUrumqi 830052China

Understanding the biomechanical properties of safflowers is essential for appropriately designing harvesting machinery and optimizing the harvesting *** is a flexible crop that lacks a basis for relevant simulation parameters,which causes difficulties in designing harvesting *** this study,a calibration method for safflowers was ***,a discrete element model was established by measuring the intrinsic parameters of a safflower,such as its geometric parameters,density,Poisson’s ratio,and modulus of ***,the contact and bonding parameters were calibrated using a combination of physical and simulation *** the contact parameter tests,the Hertz-Mindlin(no-slip)model was implemented for the stacking angle tests conducted regarding the safflower filament.A regular two-level factorial design was used to determine the important factors and perform the steepest climb ***,the Box-Behnken design was adopted to obtain the optimal contact *** the bonding parameter tests,the Hertz-Mindlin model with bonding contact was applied for the safflower shear simulation tests;moreover,the optimum bonding parameters were obtained through the central composite design *** results demonstrated that the relative errors between the simulated and measured stacking angles and maximum shear were 3.19%and 5.29%,*** a result,the safflower simulation parameters were accurately calibrated,providing a reference for appropriately setting the simulation parameters and designing key mechanical components.

关键词： safflower DEM parameter calibration shear test biomechanical properties

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Lithium sulfide:a promising prelithiation agent for high-performance lithium-ion batteries

引用

SusMat 2024年第1期4卷 34-47页

作者： Junkang Huang Weifeng Li Wenli Zhang Bixia Lin Yang Wang SiuWing Or Shuhui Sun zhenyu xing School of Chemistry South China Normal UniversityGuangzhouP.R.China Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhouP.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunP.R.China Department of Electrical and Electronic Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong Institut National de la Recherche Scientifique(INRS) Centreénergie Matériaux TélécommunicationsVarennesCanada

Lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low ***,irreversible lithium loss during the formation of the solid electrolyte interface greatly impairs energy density and *** compensate for the lithium loss,introducing an external lithium source,that is,a prelithiation agent,is an effective strategy to solve the above *** with other prelithiation strategies,cathode prelithiation is more cost-effective with simpler *** various cathode prelithiation agents,we first systematically summarize the recent progress of Li_(2)S-based prelithiation agents,and then propose some novel strategies to tackle the current *** review provides a comprehensive understanding of Li_(2)S-based prelithiation agents and new research directions in the future.

关键词： Li-ion batteries prelithiation Li2S prelithiation agent metallothermic reduction reaction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

玉米免耕播种自动调偏系统设计与试验

引用

农业机械学报 2024年第3期55卷 40-52页

作者：张振国郭全峰蒋贵菊王蕴泽邢振宇许鹏新疆农业大学机电工程学院乌鲁木齐830052 新疆智能农业装备重点实验室乌鲁木齐830052 博乐市农业农村局博乐833400

为适应新疆滴灌区宽窄行免耕种植模式,解决传统大型玉米免耕播种机播种过程中触碰根茬、无法精确约束路径、玉米粒距合格率低等问题,结合免耕播种农艺要求,在采用导航定位技术获取播种机当前位置与目标路径间偏差的基础上,设计一种玉米... 详细信息

为适应新疆滴灌区宽窄行免耕种植模式,解决传统大型玉米免耕播种机播种过程中触碰根茬、无法精确约束路径、玉米粒距合格率低等问题,结合免耕播种农艺要求,在采用导航定位技术获取播种机当前位置与目标路径间偏差的基础上,设计一种玉米免耕播种自动调偏系统。该系统主要包括避茬装置、液压执行系统和控制系统,通过建立整机力学模型,对避茬装置和液压执行系统进行运动和受力分析,确定避茬装置和液压执行系统关键结构参数,获取避茬装置最佳挂接长度和液压执行系统最大驱动力。进一步优化控制系统,实现避茬装置自动调偏及接收反馈信息功能。对免耕播种避茬装置自动调偏系统进行性能试验,试验结果表明,神经网络PID的期望调偏角最大稳态误差为0.932°,超调量全部小于1%,平均响应稳态误差小于0.9°,满足预期。田间试验结果表明,当拖拉机作业速度不大于1.0 m/s、行间秸秆覆盖量不大于1.0 kg/m^(2)时,避茬率不小于85%,纵向调整距离不大于8.6 m,玉米粒距变异系数不大于21.63%。此时播种机调偏避茬效果最佳,满足玉米免耕播种机农艺指标要求。

关键词：免耕播种机玉米自动调偏避茬装置神经网络PID控制

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

梳夹式红花采收装置集花机构优化与整机性能试验

引用

农机化研究 2024年第7期46卷 158-163页

作者：赵敏义杨双平曹卫彬张振国邢振宇新疆农业大学机电工程学院乌鲁木齐830052 石河子大学机械电气工程学院新疆石河子832000

针对研制的梳夹式红花采收装置存在采摘后的花丝掉落严重,导致花丝采集效率低的问题,提出一种新型的气吹-气吸组合式集花机构。该机构利用正压气流吹动粘附花丝脱离采摘头,同时结合梳夹装置前端安装的采摘头护罩,利用负压气流收集采摘... 详细信息

针对研制的梳夹式红花采收装置存在采摘后的花丝掉落严重,导致花丝采集效率低的问题,提出一种新型的气吹-气吸组合式集花机构。该机构利用正压气流吹动粘附花丝脱离采摘头,同时结合梳夹装置前端安装的采摘头护罩,利用负压气流收集采摘后的花丝并防止花丝掉落。通过分析花丝在正压气流中受力情况,优化了集花机构的关键结构及工作参数。为验证整机性能,以含水率≥44.5%的新疆裕民红花为对象,对集花机构优化后的梳夹式红花采收装置进行了田间试验。试验结果表明:优化后的红花采收装置花丝采净率提升至81.74%,花丝掉落率降低至2.31%,相较于优化前采净率提高了4.47%,掉落率降低了0.31%,减少了花丝损失,整机性能得到提升,可为红花机械化高效低损采收提供参考。

关键词：集花机构梳夹式采摘头护罩气吹-气吸组合红花

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Arbitrary large-gradient wavefront shaping: from local phase modulation to nonlocaldiffraction engineering

引用

Photonics Research 2022年第4期10卷 896-904页

作者： Xipu Dong Jierong Cheng Yiwu Yuan zhenyu xing Fei Fan Xianghui Wang Shengjiang Chang Institute of Modern Optics Nankai UniversityTianjin 300350China Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology Tianjin 300350China Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology Tianjin 300350China

The powerful wavefront manipulation capability of metasurfaces originates from their subwavelength or deep subwavelength elements with designable optical responses, especially phase responses. However, they usually suffer from performance degradation as the spatial phase gradient is large. To solve this issue, we propose an accurate and efficient nonlocal diffraction engineering mechanism to tailor an arbitrary large-gradient wavefront utilizing superwavelength-scale elements. The fast-varying phase profile is cut into segments according to 2π zones rather than subwavelength discretization. Each phase segment is accurately implemented by precisely tailoring the diffraction pattern of the element, where diffraction angles, efficiencies, and phases are controlled simultaneously. As proof of the concept, high numerical aperture cylindrical metalenses are designed using this method and experimentally validated at the terahertz band. The cylindrical metalens is further extended to a fullspace metalens, which enables high-quality subwavelength imaging with resolved details of 0.65λ. The proposed mechanism offers an efficient way to capture the fast-varying wavefront using relatively coarse geometries with new physical insights.

关键词： phase gradient local

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Expression, purification, and subcellular localization of phospholipase C in Dunaliella salina

引用

Journal of Oceanology and Limnology 2019年第4期37卷 1363-1371页

作者： CONG Yuting WANG Yuan YUE Jinrong xing zhenyu GAO Xiangnan CHAI Xiaojie Key Laboratory of Hydrobiology in Liaoning Province College of Fisheries and Life Science Dalian Ocean University

Plants possess effective mechanisms to respond quickly to the external environment. Rapid activation of phosphatidylinositol-specific phospholipase C (PLC) enzymes occurs after a stimulus. The PLC in Dunaliella salina plays important roles in growth and stress responses. However, the molecular basis of PLC action in D. salina remains little understood. To gain insight into the potential biological functions of this enzyme, we cloned a phospholipase C gene from D. salina in a previous study, named DsPLC (GenBank No. KF573428). Here, we present the prokaryotic expression, purification, and characterization of the DsPLC gene. The entire coding region of DsPLC was inserted into an expression vector pET32a, and the DsPLC gene was successfully expressed in Escherichia coli. The DsPLC protein was purified and identified using a polyclonal antibody and western blotting. Expressing DsPLC fused with a green fluorescent protein (GFP) in onion showed that DsPLC-GFP was localized to the intracellular membrane. Quantitative real-time PCR analysis revealed that the relative expression of the DsPLC gene was induced significantly by 3.0-mol/L NaCl at 4 h. Our results support the importance of PLC enzymes in plant defense signaling. This study provides a basis for further functional studies of the DsPLC gene and for additional analysis of the potential roles of PLC enzymes in response to abiotic stress.

关键词： Dunaliella salina DsPLC gene prokaryotic expression subcellular localization salt stress

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Oxygen-modulated metal nitride clusters with moderate binding ability to insoluble Li_(2)S_(x) for reversible polysulfide electrocatalysis

引用

InfoMat 2023年第4期5卷 1-13页

作者： Menghao Cheng zhenyu xing Rui Yan Zhenyang Zhao Tian Ma Mi Zhou Xikui Liu Shuang Li Chong Cheng College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengduthe People's Republic of China College of Biomass Science and Engineering Sichuan UniversityChengduthe People's Republic of China

Multiphase sulfur redox reactions with advanced homogeneous and heterogeneous electrochemical processes in lithium–sulfur(Li–S)batteries possess sluggish *** slow kinetics leads to significant capacity decay during charge/discharge ***,electrocatalysts with adequate sulfurredox properties are required to accelerate reversible polysulfide conversion in *** this study,we have fabricated an oxygen-modulated metal nitride cluster(C-MoN_(x)-O)that has a moderate binding ability to the insoluble Li_(2)S_(x)for reversible polysulfide electrocatalysis.A Li–S battery equipped with CMoN_(x)-O electrocatalyst displayed a high discharge capacity of 875 mAh g^(-1)at 0.5 *** capacity decay rate of each cycle was only 0.10%after 280 cycles,which is much lower than the control groups(C-MoO_(x):0.16%;C-MoN_(x):0.21%).Kinetic studies and theoretical calculations suggest that C-MoN_(x)-O electrocatalyst presents a moderate binding ability to the insoluble Li_(2)S_(2)and Li_(2)S when compared to the C-MoO_(x)and C-MoN_(x)***,the C-MoN_(x)-O can effectively immobilize and reversibly catalyze the solid–solid conversion of Li_(2)S_(2)–Li_(2)S during charge–discharge cycling,thus promoting reaction kinetics and eliminating the shuttle *** study to design oxygen-doped metal nitrides provides innovative structures and reversible solid–solid conversions to overcome the sluggish redox chemistry of polysulfides.

关键词： electrocatalysts lithium-sulfur batteries metal nitride reversible polysulfide catalysis shuttle effects Menghao Cheng

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ancient mitochondrial genome depicts sheep maternal dispersal and migration in Eastern Asia

引用

Journal of Genetics and Genomics 2024年第1期51卷 87-95页

作者： Liu Yang xing Zhang Yaning Hu Piao Zhu Hua Li zhenyu Peng Hai Xiang Xinying Zhou xingbo Zhao National Engineering Laboratory for Animal Breeding Key Laboratory of AnimalGeneticsBreeding and ReproductionMinistry of Agriculture and Rural AffairsCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding School of Life Science and EngineeringFoshan UniversityFoshanGuangdong 528225China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhenGuangdong 518083China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

Sheep have been one of the most important groups of animals since ancient ***,the knowledge of their migration routes and genetic relationships is still poorly *** investigate sheep maternal migration histories alongside Eurasian communications routes,in this study,we obtain mitochondrial genomes(mitogenomes)from 17 sheep remains in 6 Chinese sites and 1 Uzbekistan site dated 4429–3100 years before present(BP).By obtaining the mitogenomes from the sheep(4429–3556 BP)found in the Tongtian Cave site in Xinjiang,Altai region of northwest China,our results support the emergence of haplogroup C sheep in Xinjiang as early as 4429–3556 *** combined phylogenetic analyses with extant ancient and modern sheep mitogenomes suggest that the Uzbekistan-Altai region may have been a migration hub for early sheep in eastern *** least two migration events have taken place for sheep crossing Eurasia to China,one passing by Uzbekistan and Northwest China to the middle and lower reaches of the Yellow River at approximately 4000 BP and another following the Altai region to middle Inner Mongolia from 4429 BP to 2500 ***,this study provides further evidence for early sheep utilization and migration patterns in Eastern Asia.

关键词： Sheep Ancient DNA Eastern Asia Mitochondrial genome Migration Altai

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

锂硒电池研究进展

引用

化学进展 2022年第11期34卷 2517-2539页

作者：黄祺邢震宇华南师范大学化学学院广州510006 环境理论化学教育部重点实验室广州510006

锂硒电池因其高能量密度、高体积比容量和适中的输出电压等优点而成为备受关注的二次电池。然而,由于穿梭效应、较差的导电性、低活性物质利用率以及较快的容量衰减等问题,锂硒电池的实际应用受到了极大的阻碍。近些年,研究人员深入研... 详细信息

锂硒电池因其高能量密度、高体积比容量和适中的输出电压等优点而成为备受关注的二次电池。然而,由于穿梭效应、较差的导电性、低活性物质利用率以及较快的容量衰减等问题,锂硒电池的实际应用受到了极大的阻碍。近些年,研究人员深入研究了锂硒电池的充放电机理,同时也探索了各种碳材料、金属化合物等新材料作为正极载体、中间层和电解液添加剂对于电化学性能的影响。本文系统地总结了锂硒电池的电极材料、中间层和添加剂等的研究进展,并且重点介绍了在充放电机理和系统优化方面的进步,以期为锂硒电池的进一步发展提供新的思路。

关键词：锂硒电池穿梭效应电极材料电解液中间层

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cloning of Ds MAPK Gene and Construction of Antisense Expression Vector

引用

Agricultural Biotechnology 2018年第4期7卷 8-11,24页

作者： Jinrong YUE Yuting CONG Xiangnan GAO zhenyu xing Wenjing YUE Xiaojie CHAI Dalian Ocean University/Key Laboratory of Maricuhure&Stock Enhancement in North China's Sea Ministry of Agricuhure/Key Laboratory of Marine Bio-Resources Restoration and Habitat Reparation in Liaoning ProvinceDalian 116023China

In order to investigate the role of MAPK gene in adaptation of Dunaliella salina to hypersaline environment, the Ds MAPK gene of D. salina was amplified by PCR. After inverted insertion of the open reading flame ofDs MAPK gene into downstream sequence of 35S promoter of plant expression vector, an antisense expression vector of Ds MAPK gene was successfully constructed and introduced into D. salina cells by LiAc/PEG-mediated method. The expression of Ds MAPK gene in transgenic D. salina was analyzed by semi-quantitative RT-PCR method. The results showed that the expression of Ds MAPK gene in D. salina was significantly inhibited at the transcriptional level. The study laid the foundation for further identification of the function of Ds MAPK gene.

关键词： Dunaliella salina Ds MAPK Antisense expression vector Semi-quantitative RT-PCR

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：