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A New Female Cone,Araucaria beipoiaoensis *** the Middle Jurassic Tiaojishan Formation,Beipiao,Western Liaoning,China and Its Evolutionary Significance

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Acta Geologica Sinica(English Edition) 2008年第2期82卷 266-282页

作者： ZHENG shaolin zhang Lidong zhang Wu YANG Yaiun Shenyang Institute of Geology and Mineral Resources Ministry of Land and Resources Shenyang 110032 Liaoning Province China

A new species of Araucaria, Araucaria beipiaoensis sp. nov., collected from the Middle Jurassic Tiaojishan Formation, southern hill of Shebudai village, near Beipiao city, western Liaoning is based on a permineralized female cone, which is ovate to elliptical in shape, about 11 cm × 7 cm × 4.5 cm in size. The cone bears rhomboid bracts that are spirally attached, texture thicker, with wings on both sides, with a detached lamina-like apex at the tip. In inner structure the ovuliferous scales are thicker and fused with bracts at the end with a ligular sulcns. There is one wingless ovule/seed per seed-scale complex embedded in the ovuliferous scale tissue, with the micropyle directed toward the cone axis. The ovules/seeds are long ovate or elliptical in shape, 1 cm long and near the base about 3 mm in diameter; the ovule/seed integuments have begun differentiation into 3 layers： the sarcotesta, sclerotesta, and endotesta. The nucellus is free from the enclosing integuments except in the chalazal region where it is fused to the inner layer （endotesta） of integument. Some ovules show cellularized nucellar tissue. Mature seeds exhibit the papery-thin wavy nucellus characteristically near to the micropyle. The embryonic tissue appears to be four cotyledons. The morphology and structure of the cone shows a close relationship to the araucarian cones of fossil and living genera but differs from any known species. The new species is distributed in the Middle Jurassic of the northern hemisphere, especially Asia, and has important significance for the evolution of the Family Araucariaceae.

关键词： Araucaria female cone Middle Jurassic Tiaojishan Formation western Liaoning

Quantum-mechanical understanding on structure dependence of image potentials of single-walled boron nitride nanotubes

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Chinese Physics B 2024年第12期33卷 467-475页

作者： Yu zhang Zhiman zhang Weiliang Wang shaolin zhang Haiming Huang Solid State Physics&Material Research Laboratory School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research and Graduate School of Guangzhou UniversityGuangzhou 510555China School of Physics Guangdong Province Key Laboratory of Display Material and TechnologyCenter for Neutron Science and TechnologySun Yat-sen UniversityGuangzhou 510275China

The recent discovery of field emission devices based on one-dimensional nanostructures has attracted much interest in emerging applications on next-generation flat panel displays,molecule-based sensors,and so *** achieve a comprehensive understanding of surface potentials at the nano-emitters during the tunneling process,in this study we systematically investigated the image potentials of single-walled boron nitride nanotubes with different edges,diameters and lengths in the frame of a composite first-principles *** image potentials of zigzag single-walled boron nitride nanotubes are found to be dependent on the non-equivalent *** the image potentials of isolated armchair single-walled boron nitride nanotube can be well fitted with the image potential of an ideal metal sphere of a size comparable to the tube *** the contrary,the image potentials of zigzag and grounded armchair single-walled boron nitride nanotubes exhibit a strong length-dependence characteristic and are significantly different from that of an ideal metal sphere,which originates from the significant axial symmetry breaking of induced charge at the tip for the long *** correlation between the testing electron and electronic structure of single-walled boron nitride nanotube has also been discussed.

关键词： boron nitride nanotubes quantum chemistry image potentials structure dependence

Tribological properties of copper matrix composites reinforced with homogeneously dispersed graphene nanosheets

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Journal of Materials Science & Technology 2018年第10期34卷 1925-1931页

作者： Xin Gao Hongyan Yue Erjun Guo shaolin zhang Longhui Yao Xuanyu Lin Bao Wang Enhao Guan School of Materials Science and Engineering Harbin University of Science and Technology Department of Physics Dongguk University

Graphene reinforced copper matrix composites （Gr/Cu） were fabricated by electrostatic self-assembly and powder metallurgy. The morphology and structure of graphene oxide, graphene oxide-Cu powders and Gr/Cu composites were characterized by scanning electronic microscopy, transmission electronic microscopy, X-ray diffraction and Raman spectroscopy, respectively. The effects of graphene contents, applied loads and sliding speeds on the tribological behavior of the composites were investigated. The results indicate that the coefficient of friction of the composites decreases first and then increases with increasing the graphene content. The lowest friction coefficient is achieved in 0.3 wt~ Gr/Cu composite, which decreases by 65% compared to that of pure copper. The coefficient of friction of the composite does not have significant change with increasing the applied load, however, it increases with increasing the sliding speed. The tribological mechanisms of the composite under different conditions were also investigated.

关键词： Graphene nanosheets Copper matrix composites Tribological properties Microstructure

The Rise of Two‑Dimensional‑Material‑Based Filters for Airborne Particulate Matter Removal

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Advanced Fiber Materials 2023年第2期5卷 461-483页

作者： Jun Liu Enze Tian shaolin zhang Deyu Kong Kehai Liu Xuedong Bai Kaihui Liu School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research and Graduate School of Guangzhou UniversityGuangzhou 510555China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China State Key Laboratory for Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China

Airborne particulate matter(PM)has been the leading contributor to air pollution,posing a substantial risk to human health,and effective filtration technologies are ***-dimensional(2D)materials,such as graphene,graphitic carbon nitride(g-C3N4),molybdenum disulfide(MoS2),and MXenes have emerged in recent years for PM filtration due to their exception-ally large specific surface area and unique electrical ***,the most extensively used 2D materials for PM filtration followed by a summary of their fabrication methods and corresponding morphologies were *** them,the coating is the most cost-effective technique for achieving large-scale and quick *** can effectively enhance filtration efficiency and reduce pressure drop by upgrading electrostatic force and lowering the fiber *** initial and long-term performance of 2D-material-based filters was *** all 2D materials,GO is the most studied and shows the best performance by upgrading the dipole–dipole and electrostatic interaction between filters and *** study is expected to explore various 2D materials beyond GO,to evaluate filtration efficiency for submicron PM at m/s level air velocity,and to extend the service life for potential applications.

关键词： Two-dimensional material Graphene PM filtration Fabrication Electrospinning Coating

Recent progress on gas sensors based on graphene-like 2D/2D nanocomposites

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Journal of Semiconductors 2019年第11期40卷 85-98页

作者： Songyang Yuan shaolin zhang Advanced Institute of Engineering Science for Intelligent Manufacturing Guangzhou UniversityGuangzhou 510006China School of Physics and Electronic Engineering Guangzhou UniversityGuangzhou 510006China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China

Two-dimensional(2D)nanomaterials have demonstrated great potential in the field of flexible gas sensing due to their inherent high specific surface areas,unique electronic properties and flexibility ***,numerous challenges including sensitivity,selectivity,response time,recovery time,and stability have to be addressed before their practical application in gas detection *** of graphene-like 2D/2D nanocomposites as an efficient strategy to achieve high-performance 2D gas sensor has been reported *** review aims to discuss the latest advancements in the 2D/2D nanocomposites for gas *** first elaborate the gas-sensing mechanisms and the collective benefits of 2D/2D hybridization as sensor ***,we systematically present the current gas-sensing applications based on different categories of 2D/2D ***,we conclude the future prospect of 2D/2D nanocomposites in gas sensing applications.

关键词： gas sensor 2D nanomaterials 2D/2D nanocomposite heterojunction flexible sensor

三维打印碳纤维增强聚合物复合材料热残余解析解

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复合材料学报 2019年第5期36卷 1151-1158页

作者：舒小平张少林淮海工学院机械工程学院连云港222005

三维打印碳纤维增强聚合物(CFRP)复合材料因层间材料失配和打印过程中梯度降温而产生热残余现象,影响工件成形质量。本文取代简单的同步降温假设,提出了符合实际制备工艺的梯度降温概念,据此建立了三维打印正交铺层复合材料板和梁的热... 详细信息

三维打印碳纤维增强聚合物(CFRP)复合材料因层间材料失配和打印过程中梯度降温而产生热残余现象,影响工件成形质量。本文取代简单的同步降温假设,提出了符合实际制备工艺的梯度降温概念,据此建立了三维打印正交铺层复合材料板和梁的热残余变形和应力的解析解。为反映三维打印过程中随时序动态变化的制备和降温过程,考虑每层制备轮次的降温梯度并进行热残余分析,最后合成得到热残余变形和应力。讨论了4种梯度降温模式,覆盖了所有可能的三维打印工艺。以CFRP复合材料三维打印为例,验证了本文解析解的精度和可靠性,显示了同步降温假设会产生显著的误差,表明热残余水平与降温梯度成正比,讨论了铺层方式对热残余的影响。为优化三维打印CFRP复合材料的结构设计和制备工艺、降低热残余水平提供了可靠的分析方法。

关键词：残余应力三维打印纤维复合材料梯度降温

EFFECTS OF EXOTIC SPECIES ON ENDANGERED SPECIES THROUGH PREDATION

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Applied Mathematics(A Journal of Chinese Universities) 2004年第3期19卷 257-262页

作者：张少林 Dept.ofBasicCourses ZhejiangUniversityofScienceandTechnologyHangzhou310012China.

In this paper, an important problem arising from conservation biology is considered. Namely, how does the introduced species affect the survival of a native endangered species through predation? By using Kamke comparison theorem and some results in Cui and Chen’s paper (1998), some sufficient conditions that guarantee the permanence of the species and global stability of a unique positive periodic solution are obtained. Biological implication of these results are discussed. MR Subject Classification 34C25 - 92D25 Keywords ecological invasion - diffusion - permanence - predation global stability Supported by the Research Foundation of Education Department of Zhejiang Province (20038049).

关键词： MR Subject Classification 34C25 92D25

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效应幅度:外语定量研究不能忽视的测度值

外语教学理论与实践 2009年第3期 67-70,96页

作者：张少林广西师范大学

是否报告并分析研究结果的效应幅度,是判断定量研究报告质量高低的基本标准之一。本文讨论我国外语定量研究长期忽略效应幅度的现象及原因,阐述效应幅度的概念、意义,以及它与显著性水平、概率和样本容量的关系,并以便于操作的方式介绍... 详细信息

是否报告并分析研究结果的效应幅度,是判断定量研究报告质量高低的基本标准之一。本文讨论我国外语定量研究长期忽略效应幅度的现象及原因,阐述效应幅度的概念、意义,以及它与显著性水平、概率和样本容量的关系,并以便于操作的方式介绍各种常用推断统计方法中效应幅度的计算程序与判断标准。

关键词：外语测度判断标准报告质量样本容量计算程序统计方法忽略

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基于球面贝塞尔的姿态过渡与插补方法

华中科技大学学报（自然科学版） 2017年第10期45卷 75-79页

作者：张少林景奉水王硕中国科学院自动化研究所复杂系统管理与控制国家重点实验室北京100190 中国科学院大学北京100190

为了避免机器人姿态规划中反复加减速运动,节省时间,提出一种基于球面贝塞尔曲线的过渡和插补方法,用于相邻运动指令之间的姿态过渡.首先,将相邻指令的起始姿态和终点姿态表示为四元数;然后,提出球面贝塞尔曲线控制顶点的选择方法,并分... 详细信息

为了避免机器人姿态规划中反复加减速运动,节省时间,提出一种基于球面贝塞尔曲线的过渡和插补方法,用于相邻运动指令之间的姿态过渡.首先,将相邻指令的起始姿态和终点姿态表示为四元数;然后,提出球面贝塞尔曲线控制顶点的选择方法,并分析了该方法的连续性;最后,利用对球面贝塞尔曲线求导和S型加减速方法给出了插补方法,并考虑了计算的简便性.在六自由度机器人上的实验表明:角速度和旋转轴快速地过渡到下一条指令的状态,具有较好的平滑性.插补过程采用迭代求导方式,具有很好的计算简便性.

关键词：姿态过渡球面贝塞尔姿态插补姿态平滑轨迹规划