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Theoretical investigations on the growth of graphene by oxygenassisted chemical vapor deposition

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Nano Research 2024年第6期17卷 4645-4650页

作者： xiaoli Sun Chaojie yu yujia Yang Zhihao Li Jianjian Shi Wanjian Yin Zhongfan Liu Beijing Graphene Institute(BGI) Beijing 100095China School of Physics and Electronics Shandong Normal UniversityJinan 250014China College of Energy Soochow Institute for Energy and Materials InnovationsLight Industry Institute of Electrochemical Power SourcesSUDA-BGI Collaborative Innovation CenterSoochow UniversitySuzhou 215006China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China Center for Nanochemistry Beijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Recently,graphene has drawn considerable attention in the field of electronics,owing to its favorable conductivity and high carrier *** to the industrialization of graphene is its high-quality microfabrication via chemical vapor ***,many problems remain in its preparation,such as the not fully understood cracking mechanism of the carbon source,the mechanism of its substrate oxidation,and insufficient defect repair *** help close this capability gap,this study leverages density functional theory to explore the role of O in graphene *** effects of Cu substrate oxidation on carbon source cracking,nucleation barriers,crystal nucleus growth,and defect repairs are *** was found to reduce energy change during dehydrogenation,rendering the process ***,the adsorbed O in graphene or its Cu substrate can promote defect repair and edge growth.

关键词： density functional theory oxygen-assisted graphene growth chemical vapor deposition Cu substrate

Numerical simulation of the coupled dynamics model of the projectile engraving process

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International Journal of Mechanical System Dynamics 2024年第2期4卷 188-201页

作者： Shujun Zhang Xiaoting Rui Hailong yu xiaoli Dong Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingChina National Key Laboratory of Complex Multibody System Dynamics NanjingChina

The projectile engraving process directly influences the projectile motion in-bore and impacts the firing accuracy,firing safety,and barrel life of the *** this reason,attention has been focused on this research *** address the limitations of the“instantaneous engraving”hypothesis adopted in the classical interior ballistic theory,the VUAMP user subroutine,one of ABAQUS's secondary development interfaces,is utilized in this paper to realize the modeling and numerical simulation of a coupled dynamics model of the projectile engraving *** addition to facilitating engineering applications,a polynomial fitting formula of the engraving resistance obtained by simulation is proposed and then used as a supplement to establish a closed and solvable interior ballistic model considering the projectile engraving *** comparing with test data,the simulation accuracy of the coupled dynamics model is *** results reveal that the engraving process takes 3.8 ms,accounting for 26%of the whole launch process,which takes 14.6 ms,demonstrating that the process is not *** results of this paper can serve as a reference for future studies on the coupled solution of the projectile engraving process and interior ballistics of guns or gun-like equipment.

关键词： projectile engraving process engraving resistance finite element method polynomial fitting interior ballistic simulation

Learning to represent 2D human face with mathematical model

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 54-68页

作者： Liping Zhang Weijun Li Linjun Sun Lina yu Xin Ning xiaoli Dong AnnLab Institute of SemiconductorsChinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering School of Integrated CircuitsUniversity of Chinese Academy of SciencesBeijingChina Beijing Key Laboratory of Semiconductor Neural Network Intelligent Sensing and Computing Technology BeijingChina

How to represent a human face pattern?While it is presented in a continuous way in human visual system,computers often store and process it in a discrete manner with 2D arrays of *** authors attempt to learn a continuous surface representation for face image with explicit ***,an explicit model(EmFace)for human face representation is pro-posed in the form of a finite sum of mathematical terms,where each term is an analytic function ***,to estimate the unknown parameters of EmFace,a novel neural network,EmNet,is designed with an encoder-decoder structure and trained from massive face images,where the encoder is defined by a deep convolutional neural network and the decoder is an explicit mathematical expression of *** authors demonstrate that our EmFace represents face image more accurate than the comparison method,with an average mean square error of 0.000888,0.000936,0.000953 on LFW,IARPA Janus Benchmark-B,and IJB-C *** results show that,EmFace has a higher representation performance on faces with various expressions,postures,and other ***,EmFace achieves reasonable performance on several face image processing tasks,including face image restoration,denoising,and transformation.

关键词： artificial neural networks face analysis image processing mathematics computing

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发动机进气系统结构参数优化设计与试验

中国机械工程 2017年第10期28卷 1172-1177,1182页

作者：李强俞小莉浙江科技学院机械与汽车工程学院杭州310023 浙江大学动力机械及车辆工程研究所杭州310027

为研究进气系统结构参数对发动机动力性的影响,对进气系统的流场分布和流动特性进行了多物理场耦合数值模拟分析。分析了限流阀的进气锥角和扩散锥角对出口处平均速度和平均压力等指标的影响规律;对稳压腔的结构参数进行正交优化设计,... 详细信息

为研究进气系统结构参数对发动机动力性的影响,对进气系统的流场分布和流动特性进行了多物理场耦合数值模拟分析。分析了限流阀的进气锥角和扩散锥角对出口处平均速度和平均压力等指标的影响规律;对稳压腔的结构参数进行正交优化设计,据此获得其对各缸流速均匀性的影响规律。结果表明,稳压腔的腔体直径对各缸流速均匀性的影响最明显,而腔体长度的影响相对最小;限流阀对发动机低速工况充气效率的影响较小,而对中高速工况变化趋势的影响较大。对优化后的进气系统进行了发动机台架试验,验证了MOTEC ECU修正的电喷控制策略能有效改善发动机动力性。

关键词：发动机进气系统数值模拟优化设计

山豆根多糖对小鼠脾淋巴细胞炎性反应的调控机制

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基因组学与应用生物学 2024年第8期43卷 1379-1388页

作者：柏晶晶周家芳贾妮娜黄昌巧袁海峰余小丽蒋丽群胡效东李艳华胡庭俊广西大学动物科学技术学院南宁530004

本研究旨在基于转录组测序技术探讨山豆根多糖(Sophora subprosrate polysaccharide,SSP)对小鼠脾淋巴细胞炎性反应的调控机制。本研究采用小鼠原代脾淋巴细胞,设置细胞对照组和400μg/mL SSP药物组,基于Illumina NovaSeq 6000测序技术... 详细信息

本研究旨在基于转录组测序技术探讨山豆根多糖(Sophora subprosrate polysaccharide,SSP)对小鼠脾淋巴细胞炎性反应的调控机制。本研究采用小鼠原代脾淋巴细胞,设置细胞对照组和400μg/mL SSP药物组,基于Illumina NovaSeq 6000测序技术的全转录组测序数据,用DeSeq 2.0软件对mRNA、lncRNA和miRNA进行差异分析。利用基因本体论(gene ontology,GO)和京都基因和基因组百科全书(kyoto encyclopedia of genes and genomes,KEGG)富集对差异表达基因(differentially expressed genes,DEGs)进行功能分析。在DEGs中随机筛选出与炎性反应相关的mRNA、lncRNA和miRNA,利用RT-qPCR技术对测序结果进行验证。结果显示,与细胞对照组相比,400μg/mL SSP药物组共获得658个DEGs,其中373个上调,285个下调;GO功能和KEGG通路富集分析结果显示,DEGs与免疫及炎性反应等相关,主要富集在核苷酸结合寡聚化结构域(nucleotide-binding oligomerization domain,NOD)样受体信号通路、核因子κB(nuclear factor kappa-B,NF-κB)信号通路、视黄酸诱导型基因I(retinoic acid-inducible gene-I,RIG-I)样信号通路、调控干细胞多功能性信号通路、FOXO(forkhead box O)信号通路、趋化因子信号通路、丝裂原活化蛋白激酶(mitogen activated protein kinase,MAPK)信号通路和C型凝集素受体信号通路;RT-qPCR结果与全转录组测序的基因表达水平保持一致;对转录组DEGs的分析结果显示,山豆根多糖可能通过NF-κB信号通路和NOD样受体信号通路等下游炎症信号通路和免疫相关通路调控机体的炎性反应,该研究为山豆根多糖的开发应用提供了一定参考。

关键词：山豆根多糖小鼠脾淋巴细胞转录组学炎性反应

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曲轴疲劳裂纹扩展模式的时序方法预测

农业机械学报 2007年第9期38卷 163-167页

作者：周迅俞小莉浙江大学动力机械与车辆工程研究所

在外界载荷和构件内部材料特性的共同作用下,机械构件的疲劳裂纹的扩展行为往往具有阶段性,在不同的阶段内伴随不同的行为特性。为了研究这种阶段性并对这种阶段性进行预测,对曲轴疲劳试验过程中谐振台架的振动加速度进行了测录,并采用... 详细信息

在外界载荷和构件内部材料特性的共同作用下,机械构件的疲劳裂纹的扩展行为往往具有阶段性,在不同的阶段内伴随不同的行为特性。为了研究这种阶段性并对这种阶段性进行预测,对曲轴疲劳试验过程中谐振台架的振动加速度进行了测录,并采用经典时序方法对这一监测信号进行建模,计算了其在各个时间段中的异常度曲线。与曲轴疲劳裂纹扩展速率曲线进行对比,结果表明时序方法对裂纹扩展模式具有一定的预测能力。

关键词：曲轴疲劳裂纹预测时序方法

BnaWRKY75 positively regulates the resistance against Sclerotinia sclerotiorum in ornamental Brassica napus

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Horticultural Plant Journal 2024年第3期10卷 784-796页

作者： Kexin yu Yijie Zhang Xiaoyuan Fei Luyue Ma Rehman Sarwar xiaoli Tan Zheng Wang School of Life Sciences Jiangsu UniversityZhenjiangJiangsu 212013China School of Food and Biological Engineering Jiangsu University ZhenjiangJiangsu 212013China Key Laboratory for Theory and Technology of Intelligent Agricultural Machinery and Equipment Jiangsu UniversityZhenjiangJiangsu 212013China

With the development of tourism at home and abroad,Rapeseed(Brassica napus)has become an important ornamental ***,its ornamental value at the inflorescence stage is greatly reduced by Sclerotinia *** of important genes in the defense responses is critical for molecular breeding,which is an important strategy for controlling the *** this study,we isolated a *** WRKY transcription factor gene,***75 was found to encode a nucleus-localized protein and exhibited relatively high expression in the *** thaliana transgenic plants expressing BnaWRKY75 showed enhanced resistance to ***,and both ProBnaWRKY75:GUS and gene expression analyses showed that BnaWRKY75 was highly responsive to *** infection,indicating the involvement of BnaWRKY75 in response to this ***,overexpression(OE)of BnaWRKY75 in *** significantly enhanced the resistance to ***,whereas the resistance was reduced in RNAi transgenic *** ***,the BnaWRKY75-OE *** plants exhibited constitutive activation of salicylic acid-,jasmonic acid-,and ethylene-mediated defense responses and the inhibition of both H_(2)O_(2)and O_(2)·^(-)accumulation in response to this *** contrast,BnaWRKY75-RNAi plants showed a reverse pattern,suggesting that BnaWRKY75 is involved in hormonal signaling pathways and in the control of reactive oxygen species *** conclusion,these data indicate that BnaWRKY75,a regulator of multiple defense responses,positively regulates resistance against ***,which may guide the improvement of resistance in rapeseed.

关键词： Brassica napus BnaWRKY75 Defense response Sclerotinia sclerotiorum

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谐振式曲轴弯曲疲劳试验恒载荷控制方法

农业机械学报 2006年第12期37卷 168-171,181页

作者：周迅俞小莉浙江大学动力机械与车辆工程研究所

为研究谐振式曲轴弯曲疲劳试验中试件裂纹扩展对谐振系统载荷放大特性的影响,且在此基础上实现试验系统的高精度恒载荷控制,对谐振系统的振动模型进行了详细的模态和谐响应有限元分析,通过对计算阻尼系数合理修正,有限元分析的结果可以... 详细信息

为研究谐振式曲轴弯曲疲劳试验中试件裂纹扩展对谐振系统载荷放大特性的影响,且在此基础上实现试验系统的高精度恒载荷控制,对谐振系统的振动模型进行了详细的模态和谐响应有限元分析,通过对计算阻尼系数合理修正,有限元分析的结果可以很好地符合试验结果。根据多种裂纹尺寸条件下的分析结果,建立了试件裂纹尺寸、试件承载水平与系统振动特性之间的关系。讨论了为实现恒载荷特性,在试验过程中对加载频率进行调整的必要性,提供了以振动加速度为参考状态变量进行恒载荷控制的依据。

关键词：曲轴疲劳试验恒载荷控制有限元分析

Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang Jia yu Zhe Pu Wenhui Guo Ruoqi Yang yu Wen Zhijiang Rong Hui Wang xiaoli Wu Bo Wang Hongyan Sun School of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China School of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization