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Parallel optical coherence tomography using a CCD camera

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Chinese Optics Letters 2004年第8期2卷 475-476页

作者：屈军乐 ravi s.jonnal donald t.miller Institute of Optoelectronics Shenzhen University Shenzhen 518060 School of Optometry Indiana University Bloomington IN 47405 USA school of Optometry Indiana University Bloomington IN 47405 USA school of Optometry Indiana University Bloomington IN 47405 USAarallel optical coherence tomography is demonstrated using a 12-bit scientific-grade charge-coupled device array. A superluminescent diode in combination with a free-space Michelson interferometer was employed to achieve 10-μm axial resolution and 1.1-μm transverse resolution on a 902×575 /μm2 field of view. We imaged a test mirror and bovine retinal tissue using a four-step phase shift method.

Parallel optical coherence tomography is demonstrated using a 12-bit scientific-grade charge-coupled device array. A superluminescent diode in combination with a free-space Michelson interferometer was employed to achieve 10-μm axial resolution and 1.1-μm transverse resolution on a 902×575 /μm2 field of view. We imaged a test mirror and bovine retinal tissue using a four-step phase shift method.

关键词： Cameras Charge coupled devices Interferometers Phase shift semiconductor diodes

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视网膜单细胞成像技术研究

激光生物学报 2004年第3期13卷 194-197页

作者：屈军乐 jonnal R s t.orn K e miller D t 深圳大学光电子学研究所中国广东深圳518060 Indiana University school of Optometry

建立了一台基于37单元变形镜、shack-hartman波前像差传感器和12位科研级CCD相机的自适应光学视网膜相机。采用一个中心波长为679nm的超辐射二极管(sLD)作为相机的光源,通过将超辐射二极管和多模光纤耦合,显著减小了sLD光源的空间相干性... 详细信息

建立了一台基于37单元变形镜、shack-hartman波前像差传感器和12位科研级CCD相机的自适应光学视网膜相机。采用一个中心波长为679nm的超辐射二极管(sLD)作为相机的光源,通过将超辐射二极管和多模光纤耦合,显著减小了sLD光源的空间相干性,从而消除了散斑噪声对成像的影响。多模光纤的输出提供了一种高亮度、均匀照明的光源,使人眼视网膜单细胞成像的速度达到4.8幅秒。

关键词：自适应光学视网膜像差变形镜 shack-hartman波前像差传感器

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(english edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAeI H.GHANDVAR e.JUMAeV s.KHAtIR t.CUONG-Le school of Mechanical engineering Babol Noshirvani University of Technology Department of Mechanical engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for engineering Application and technology solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Development of an AO-OCt camera for imaging single cells and layers of the human retina

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Development of an AO-OCT camera for imaging single cells and...

中国光学学会2004年学术大会

作者： jonnal ravi s t.orn karen e miller donald t school of Optometry Indiana University Bloomington IN 47405 USA school of Optometry Indiana University Bloomington IN 47405 USA school of Optometry Indiana University Bloomington IN 47405 USA

An en face coherence gated camera equipped with adaptive optics (AO) has been constructed for imaging single cells in the living human retina the high axial resolution of coherence gating combined wit

关键词： optical coherence tomography coherence gating adaptive optics eye retina cone photoreceptors.

来源： cnki会议评论

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美国页岩油气地质特征及勘探开发进展

石油勘探与开发 2024年第4期51卷 807-828页

作者： MCMAHON t P LARsON t e ZHANG t sHUsteR M 美国德克萨斯大学奥斯汀分校杰克逊地质科学学院经济地质局奥斯汀78758-4445德克萨斯州美国

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比... 详细信息

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比世)、早二叠世、晚侏罗世和晚白垩世(塞诺曼期—土伦期),构造沉积环境主要包括克拉通内盆地、前陆盆地和被动大陆边缘盆地。古生界富烃页岩主要分布于以下6个盆地:阿巴拉契亚盆地(尤蒂卡页岩和马塞勒斯页岩)、阿纳达科盆地(伍德福德页岩)、威利斯顿盆地(巴肯页岩)、阿卡马盆地(费耶特维尔页岩)、沃思堡盆地(巴内特页岩)和二叠盆地(狼营组和斯帕瑞组/骨泉组页岩)。中生界富烃页岩主要发育在西墨西哥湾盆地(海恩斯维尔组和鹰滩组)和落基山盆地群(以丹佛和粉河盆地的尼尔布拉勒组页岩为主)。通过对各页岩区带的详细分析发现,页岩的岩相和矿物成分存在差异,“页岩储层”并非只是页岩,很多情况下页岩油气还产自粉砂岩和碳酸盐岩等多种岩石类型。美国的页岩油气资源丰富,页岩油地质资源量超过0.246×1012 t,页岩气地质资源量超过290×1012 m3。在开启“页岩革命”的水平井水力压裂技术出现之前,美国经过了长达20年的勘探开发实践和理论技术积累。自2007年至2023年,美国页岩油气产量从约11.2×104t/d油当量增加到超过300.0×104t/d油当量,2017年页岩油气产量超过了常规油气,2023年在油气总产量中的占比增加到60%以上。页岩油气的开发主要得益于钻完井技术的改进,“立体开发”的攻关,以及重复压裂、提高原油采收率和“U”形井等技术的应用。基于美国丰富的页岩资源基础和技术的不断进步,页岩油气的产量将继续为全美的油气生产做出更大贡献。

关键词：美国页岩油页岩气页岩储层非常规储层油气产量资源评价

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Geometrical, microstructural and mechanical characterization of pulse laser welded thin sheet 5052-H32 aluminium alloy for aerospace applications

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transactions of Nonferrous Metals society of China 2019年第4期29卷 667-679页

作者： t.e.ABIOYe H.ZUHAILAWAtI s.AIZAD A.s.ANAsYIDA structural Materials Niche Area School of Materials and Mineral Resources Engineering Engineering CampusUniversiti Sains Malaysia Industrial and Production engineering Department School of Engineering and Engineering TechnologyFederal University of Technology Akure

Pulse laser welding of 0.6 mm-thick AA5052-H32 was performed to determine the optimum set of parameters including laser pulse current,pulse frequency and pulse duration that meets the AWs D17.1 specifications for aerospace *** microstructure and mechanical properties of the weldments were also *** between the parameters and weld bead geometry were *** quality weld joints without solidification crack that met AWs D17.1 requirements were obtained at(I)high pulse energy(25 J)and high average peak power(4.2 kW)and(II)low pulse energy(17.6 J)and low average peak power(2.8 kW).the weld joint formed at lower heat energy input exhibited finer dendritic grain *** vapourisation and hard phase compound(Al0.5Fe3si0.5)formation decreased in the weld joint formed at lower heat energy ***,the tensile strength of the weldment formed at lower heat energy input(168 MPa)is by a factor of 1.15 higher but showed^29%decrease in hardness(111 HV0.1)at the joint when being compared with the weldment formed at higher heat energy *** parameters selection is critical to obtaining 0.6 mm-thick AA5052-H32 pulse laser weld joints that meet AWs D17.1 requirements for aircraft structures.

关键词： pulse laser welding aluminium alloy thin sheet microstructure mechanical properties solidification cracking intermetallic compound

Phase transfer Catalysis: Oxidation of 2-Methyl-1-butanol

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Chinese Journal of Chemical engineering 2014年第9期22卷 1000-1004页

作者： t.sankarshana e.Yadagiri J.s.N.Murthy University College of technology Osmania University

In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. the present study involves the phase transfer catalyzed oxidation of 2-methyl-l-butanol by quaternary ammonium permanganate （tricaprylyl methyl ammonium permanganate）. the attempt was to compare the kinetics under homogeneous and heterogeneous conditions. experiments were conducted in a batch reactor to determine the kinetics under homogeneous conditions. A baffled horosilicate agitated reactor was used to find the enhancement factor and the kinetics under heterogeneous conditions. the rate constants determined under both homogeneous and heterogeneous conditions agreed very weU. the oxidation was found to be first order with respect to each of the reactants, quaternary ammonium permanganate and the alcohol, resulting in an overall second order rate expression. Aliquat336 （tricaprylylmethylammonium chloride） was found to be the best compared with the other catalysts tested （triethylbenzylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide and tetrabutylammonium hydrogen sulfate） and it gave an enhancement factor of 9.8.

关键词： Aliquat336Phase transfer catalysisPotassium permanganate2-Methyl-l-butanolenhancement factor

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小麦抗白粉病基因Pm12的RFLP标记

中国科学（B辑） 1993年第6期23卷 589-594页

作者：贾继增 t. e. miller s. M. Reader M. D. Gale 中国农业科学院作物品种资源研究所北京100081 英国植物研究中心剑桥实验室Norwich NR4 7UJ

春小麦品系Line 31携带有一个来自斯卑尔脱山羊草的显性抗白粉病基因Pm 12(miller等,1988)。16个RFLP(restriction fragment length polymorphism)探针用于鉴定Line 31及其亲本,结果表明Line 31是一个6B/6s易位系。用5个探针所进行的连... 详细信息

春小麦品系Line 31携带有一个来自斯卑尔脱山羊草的显性抗白粉病基因Pm 12(miller等,1988)。16个RFLP(restriction fragment length polymorphism)探针用于鉴定Line 31及其亲本,结果表明Line 31是一个6B/6s易位系。用5个探针所进行的连锁分析进一步揭示Pm 12位于易位染色体的着丝点附近,与6s长臂上的α-淀粉酶位点(α-Amy-s1)紧密连锁,遗传距离仅为1.1 cM。本研究结果表明RFLP技术在鉴定小麦外源染色体及外源基因上具有广阔的应用前景。

关键词：小麦基因多态性抗白粉病

Correlation of microstructural and corrosion characteristics of quaternary shape memory alloys Cu-Al-Ni-X(X=Mn or ti)

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transactions of Nonferrous Metals society of China 2015年第4期25卷 1158-1170页

作者： s.N.sAUD e.HAMZAH t.ABUBAKAR H.R.BAKHsHesHI-RAD Faculty of Mechanical engineering Universiti Teknologi MalaysiaJohor Bahru 81310 Johor Malaysia

the effects of different contents(0.4%, 0.7%, and 1.0%, mass fraction) of Mn or ti additions on the micro structure, shape memory effect and the corrosion behaviour of Cu-Al-Ni shape memory alloys were studied by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, differential scanning calorimetry and electrochemical and immersion tests in NaCl solution. It was observed that the microstructure, shape memory effect and corrosion characteristics are highly sensitive to the composition variations. It was found that the highest strain recovery was with 0.7% addition of Mn or ti. this may be attributed to the presence of precipitation with a high volume fraction and the grain refinement. the electrochemical test showed that the formation of oxide layers in both Cu-Al-Ni-Mn and Cu-Al-Ni-ti shape memory alloys(sMAs) provided good passivation which enhanced the corrosion resistance of the alloys. Immersion test showed that in Cu-Al-Ni-Mn sMAs, pitting corrosion occurred through feebleness in the oxide layer. A corrosion product adjacent to the pits was rich in Al/Mn oxide and depleted in Cu while inside of the pit it was rich in Cu. In Cu-Al-Ni-ti sMAs, localized corrosion occurred on the surface of the specimens and dealuminization attack was also observed in the matrix.

关键词： Cu-Al-Ni alloy shape memory effect electrochemical test alloying addition microstructure