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Chinese Journal of Structural Chemistry 2006年第10期25卷 1243-1249页

作者： qian hui-fen HUANG Wei LI hui-hui YAO Cheng College of Sciences Nanjing University of Technology Nanjing 210009 China State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-（＋）-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate （1S,3R）-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework.

关键词： chiral amino acids and amino alcohols (1S,3R)-3-amino-2,2,3-trimethyl-cyclopentane-1-carboxylic acid hydrochloride hydrogen-bonding interactions crystal structures

Complex interactions among insect viruses-insect vector-arboviruses

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Insect Science 2024年第3期31卷 683-693页

作者： hui Wang qian Chen Taiyun Wei State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Vector-borne Virus Research CenterFujian Agriculture and ForestryUniversityFuzhouChina

Insects are the host or vector of diverse viruses including those that infect vertebrates,plants,and *** viruses reside inside their insect hosts and are vertically transmitted from parent to *** insect virus-host relationship is intricate,as these viruses can impact various aspects of insect biology,such as development,reproduction,sex ratios,and ***-borne viruses(arboviruses)that cause substantial global health or agricultural problems can also be vertically transmitted to insect vector *** infections with insect viruses and arboviruses are common in *** coinfections involve complex interactions,including synergism,dependence,and *** studies have shed light on the influence of insect viruses on the competence of insect vectors for *** this review,we focus on the biological effects of insect viruses on the transmission of arboviruses by *** also discuss the potential mechanisms by which insect viruses affect the ability of hosts to transmit arboviruses,as well as potential strategies for disease control through manipulation of insect *** of the interactions among insect vectors,insect viruses and arboviruses will provide new opportunities for development of innovative strategies to control arbovirus transmission.

关键词： arbovirus insect biology insect vectors insect virus interaction transmission

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三坐标测量机驱动的摄像机标定技术

光学精密工程 2010年第4期18卷 952-957页

作者：黄风山钱惠芬河北科技大学机械电子工程学院河北石家庄050018 天津大学精密测试技术及仪器国家重点实验室天津300072

为了降低摄像机的标定费用和提高标定精度,提出了一种基于三坐标测量机平动的摄像机标定技术,对该技术的原理、数学模型、标定步骤和标定精度进行了研究。根据摄像机标定的基本原理,利用三坐标测量机沿X、Y、Z轴移动和正交精度都很高的... 详细信息

为了降低摄像机的标定费用和提高标定精度,提出了一种基于三坐标测量机平动的摄像机标定技术,对该技术的原理、数学模型、标定步骤和标定精度进行了研究。根据摄像机标定的基本原理,利用三坐标测量机沿X、Y、Z轴移动和正交精度都很高的特点,以三坐标测量机带动待标定摄像机产生和白色陶瓷标准球球心(标定特征点)在X、Y、Z轴方向上的相对平动,得到标定特征点在测头坐标系中不同位置的坐标;在每一个确定位置,摄像机拍摄标定特征点的像,经图像处理后,计算出像点在计算机帧存坐标系中的坐标。引入测头坐标系,建立了该项摄像机标定技术的数学模型,给出了标定步骤,组建了标定系统。比对标定实验结果表明,基于三坐标测量机平动的摄像机标定系统与专用标定系统的标定精度相当,数据相差在±1μm以内,满足工程实际精度要求,成本低、标定效率高。

关键词：摄像机标定三坐标测量机平动测头坐标系数学模型

CdTe QDs@SiO2 composite material for efficient photocatalytic degradation of tetracycline composites

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Green Chemical Engineering 2024年第4期5卷 533-542页

作者： Taihang Zhou fen Qiao Sen qian Shoaib Muhammad Haitao Li Yanzhen Liu School of Energy & Power Engineering Jiangsu University Institute for Energy Research Jiangsu University

In the contemporary context,tetracycline is widely utilized as a prevalent antibiotic in various facets of ***,the excessive use of antibiotics has caused visible environmental ***,the scientific community has increasingly focused on developing catalysts that exhibit exceptional efficacy in the proficient degradation of *** this study,a novel nanomaterial was developed to encapsulate Cd Te quantum dots （QDs） with a *** distinct synthesis approach generated a composite material that showed heterogeneity and considerably increased the contact area with ***,the transfer of photoelectron to the SiO2spheres was significantly improved,leading to a more efficient separation during the catalytic *** study investigated how different factors,such as the loading of the catalyst,the initial concentration of tetracycline,p H levels,and the wight ratio of Cd Te QDs （SiO2+Cd Te QDs） affected the effectiveness of photocatalytic tetracycline *** findings indicated that the optimal degradation efficiency was observed at a catalyst concentration of 0.25 g/L and a solution p H of 9,leading to an impressive degradation rate of 96%within a mere 2 h timeframe.

关键词： Photocatalysis Silica-based catalyst Photocatalytic degradation Photocatalytic mechanism

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光笔式单摄像机三维坐标视觉测量系统

光电工程 2007年第4期34卷 69-72页

作者：黄风山钱惠芬河北科技大学机械电子工程学院

提出了一种光笔式单摄像机三维坐标视觉测量系统,系统主要由一支光笔、一架摄像机、一台笔记本电脑组成。光笔是一种手持式触发测头,在笔体上装有三个与球形笔尖测头中心成一条直线的点光源(发光二极管)。测量时使笔尖测头接触被测物体... 详细信息

提出了一种光笔式单摄像机三维坐标视觉测量系统,系统主要由一支光笔、一架摄像机、一台笔记本电脑组成。光笔是一种手持式触发测头,在笔体上装有三个与球形笔尖测头中心成一条直线的点光源(发光二极管)。测量时使笔尖测头接触被测物体表面,摄像机摄取笔体上三个发光二极管的像,由三个发光二极管的像面坐标就可计算出被测点的三维坐标。运用三点透视原理(P3P)建立了系统的数学模型并推导出了被测点坐标的求解公式。在三坐标测量机上做对比实验,实验测试结果表明,该系统达到了大尺寸现场测量要求的精度。

关键词：三维坐标测量光笔单摄像机视觉

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光笔式单摄像机三维坐标视觉测量系统建模

光电子．激光 2007年第1期18卷 85-88页

作者：黄风山钱惠芬河北科技大学机械电子工程学院天津大学精密测试技术与仪器国家重点实验室天津300072

提出了一种光笔式单摄像机三维坐标视觉测量系统,其主要由光笔、摄像机和笔记本电脑组成。测量时,使笔尖测头接触被测物体表面,摄像机摄取笔体上3个发光二极管的像,由3个发光二极管的像面坐标就可计算出被测点的三维坐标。运用三点透视... 详细信息

提出了一种光笔式单摄像机三维坐标视觉测量系统,其主要由光笔、摄像机和笔记本电脑组成。测量时,使笔尖测头接触被测物体表面,摄像机摄取笔体上3个发光二极管的像,由3个发光二极管的像面坐标就可计算出被测点的三维坐标。运用三点透视问题(P3P)原理建立了系统的数学模型,并用摄像机模型中的坐标变换原理证明了该模型解的唯一性,推导出了被测点坐标的求解公式。在三坐标测量机上做了对比实验,结果表明,该系统达到了大尺寸现场测量要求的精度。

关键词：光笔单摄像机建模三维坐标测量视觉

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激光跟踪测距三维坐标视觉测量系统建模

光电子．激光 2007年第11期18卷 1333-1335页

作者：黄风山钱惠芬河北科技大学机械电子工程学院

提出了一种激光跟踪测距视觉坐标测量系统,主要由摄像机、激光测距仪、计算机和光笔组成。测量时摄像机测量光笔上各光反射点的方向,激光测距仪跟踪捕捉并测量出某一光反射点到激光测距仪的距离,由测得的方向和距离计算出光笔笔尖接触... 详细信息

提出了一种激光跟踪测距视觉坐标测量系统,主要由摄像机、激光测距仪、计算机和光笔组成。测量时摄像机测量光笔上各光反射点的方向,激光测距仪跟踪捕捉并测量出某一光反射点到激光测距仪的距离,由测得的方向和距离计算出光笔笔尖接触点的三维坐标。根据n点透视问题(PnP)原理建立了系统的数学模型,激光测距仪测得的距离参数的引入,使得该数学模型可以线性求解,而且解具有唯一性。依据冗余技术给出了被测点三维坐标的求解方程组及其解法。和单摄像机视觉坐标测量系统的比对实验结果表明:在Z、Y和X轴方向上的测量稳定性精度可分别提高0.366、0.031和0.011 mm。

关键词：跟踪测距三维坐标视觉测量 n点透视问题(PnP) 冗余技术

Tuning heterogeneous microstructures to enhance mechanical properties of nano-TiN particle reinforced Haynes 230 composites by laser powder bed fusion

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Rare Metals 2024年第9期43卷 4548-4565页

作者： Wen-Jie Liu hui Li qian-Xing Yin He-Jun Du School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

Laser powder bed fusion(LPBF)is considered to be one of the most promising additive manufacturing technologies for producing components with geometries and high geometrical precision that are unattainable by traditional *** superalloy exhibits exceptional mechanical and high-temperature performances,rendering it a prime candidate for advanced aero-engine *** the high demand for LPBF-manufactured superalloys,the superalloy is one of the materials manufactured difficultly by LPBF due to their large laser absorptivity fluctuation,poor molten pool stability and sharp temperature ***,superalloys are characterized by severe pores,undesirable coarse columnar grains and poor mechanical *** this work,the effect of nano-TiN particles on defects,molten pool characteristics and microstructure and performance of the composites were *** 4.5 wt%TiN/Haynes230 samples exhibited exceptional nanohardness and elastic modulus with maximum values reaching 5.53 GPa and 240.03 GPa,*** superior mechanical properties were attributed to the combined effects of spatter and gas pore inhibition,grain refinement and duplex nanophases ***,the stability of molten pool was enhanced,and spatter was effectively suppressed by adding nano-TiN particles,while grain refinement and columnar to equiaxed transitions were ***,the matrix exhibited a high dislocation density due to a significant hindrance of dislocation movement caused by massive nano-phases(e.g.,TiN and M_(23)C_(6)),resulting in the formation of extensive dislocation tangles and *** work offers novel insights into the role of nanoparticles reinforced superalloy composites by LPBF.

关键词： Composites Laser powder bed fusion Molten pool characteristics Microstructure Mechanical properties

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： Ding-qian Dong feng-yuan He Xin-hui Chen hui Li Kai-hua Shi hui-wen Xiong Xin Xiang Li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

Significant annealing-induced hardening effect in nanolaminate d-nanotwinne d(CrCoNi)_(97.4)Al_(0.8)Ti_(1.8)me dium-entropy alloy by severe cold rolling

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Journal of Materials Science & Technology 2024年第3期170卷 156-166页

作者： Shuqing Yuan hui Fu Lei qian Chi Fai Cheung Xu-Sheng Yang State Key Laboratory of Ultra-precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518060China

Due to the easy coarsening caused by poor thermal stability,the verified annealing-induced hardening in nanograined metals can only maintain at a relatively low-temperature *** this study,a nanolam-inated(CrCoNi)_(97.4)Al_(0.8)Ti_(1.8)medium-entropy alloy with an average lamellae thickness of∼20 nm embedded by thinner nanotwins was fabricated by severe cold rolling to achieve superior thermal *** with the conventional nanotwinned CrCoNi with nanotwins inside ultra-fined grains,the hier-archical nanolaminated-nanotwinned(CrCoNi)_(97.4)Al_(0.8)Ti_(1.8) exhibits a significant annealing-induced hard-ening effect,i.e.,hardness increasing from∼250 HV in the original specimen to∼500 HV in the cold-rolled status and finally∼630 HV after annealing at 600℃for 1 *** microstructure characterizations reveal that the reduced dislocation density and formation of L1_(2)ordered domain are mainly responsible for such hardening effect,which is facilitated by the effectively suppressed coarsening with annealing temperature,i.e.,slow detwinning process and well-retained low-angle nanolamellar *** coarsening mechanisms from the cold-rolled nanolamellae to the fully recrystallized micro-equiaxed structures under the annealing temperatures ranging from 400 to 800℃ were also elucidated by atomic observations.

关键词： Annealing-induced hardening Thermal stability Nanolaminated-nanotwinned structure CrCoNi Detwinning Grain boundary migration