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A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

Science china Earth Sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3 1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china 2 Graduate School of Chinese Academy of Sciences,Beijing 100049,china 3 Department of Science and Technology,Bryant university,Smithfield RI 02917,USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China Department of Science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification,systematics,and palaeoclimatological *** recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with suffi-cient size a critical technique in palaeoclimatological ***,for plants with originally thin and fragile cuticles,e.g.,most deciduous plants,conventional techniques sometimes fail to obtain cuticular membranes with sufficient size,or sometimes unable to recover *** has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeoclimatological ***,we describe a new method using clear nail polish as a medium to "strengthen" the originally thin and fragile cuticles prior to maceration *** demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile ***,with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living representative,***,as a comparative reference,has been widely used as a model genus for the study of evolution of plants,palaeoclimatological reconstruction,and plant adaptation to climate *** its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious *** new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词：植物化石叶角质层膜制备叶表皮大气二氧化碳浓度化石角质层气孔频率落叶植物

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Organic thin-film solar cells:devices and materials

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Science china Chemistry 2012年第4期55卷 553-578页

作者： LI ZhiGang1, ZHAO XinYan2, LI Xin1,2, GAO ZhiQiang1, MI BaoXiu1 & HUANG Wei2 1Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering, Nanjing university of Posts & Telecommunications, Nanjing 210046, china 2Key Laboratory for Organic electronics & Information Displays (KLOEID) institute of Advanced Materials (IAM), Nanjing university of Posts & Telecommunications, Nanjing 210046, china Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering Nanjing University of Posts & Telecommunications Nanjing China Key Laboratory for Organic electronics & Information Displays (KLOEID) institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing China

In recent years, the performance of organic thin-film solar cells has gained rapid progress, of which the power conversion efficiencies (ηp) of 3%-5% are commonly achieved, which were difficult to obtain years ago and are improving steadily now. The ηp of 7.4% was achieved in the year 2010, and ηp of 9.2% was disclosed and confirmed at website of Mitsubishi Chemical in April, 2011. The promising future is that the ηp of 10% is achievable according to simulation results. Apparently, these are attributed to material innovations, new device structures, and also the better understanding of device physics. This article summarizes recent progress in organic thin-film solar cells related to materials, device structures and working principles. In the device functioning part, after each brief summary of the working principle, the methods for improvements, such as absorption increment, organic/electrode interface engineering, morphological issues, are addressed and summarized accordingly. In addition, for the purpose of increasing exciton diffusion efficiency, the benefit from triplet exciton, which has been proposed in recent years, is highlighted. In the active material parts, the chemical nature of materials and its impact on device performance are discussed. Particularly, emphasis is given toward the insight for better understanding device physics as well as improvements in device performance either by development of new materials or by new device architecture.

关键词：有机太阳能电池新材料新设备功率转换效率器件性能器件结构器件物理工作原理

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基于微细加工技术的微谐振腔型滤波器

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中国激光 2004年第6期31卷 659-661页

作者：宋康李以贵陈水良上海交通大学微纳米技术研究院薄膜与微细技术教育部重点实验室上海200030

　设计了一种新工艺———利用硅微结构直接作为模具来制作微小固体染料激光器谐振腔型滤波器。首先通过组合刻蚀工艺制作硅模具 ,再利用硅模具复制得到微谐振腔。组合刻蚀工艺是采用深层反应离子刻蚀 (deep RIE)再结合EPW湿法刻蚀 (一... 详细信息

　设计了一种新工艺———利用硅微结构直接作为模具来制作微小固体染料激光器谐振腔型滤波器。首先通过组合刻蚀工艺制作硅模具 ,再利用硅模具复制得到微谐振腔。组合刻蚀工艺是采用深层反应离子刻蚀 (deep RIE)再结合EPW湿法刻蚀 (一种各向异性刻蚀技术 )。由于EPW湿法刻蚀对〈110〉面刻蚀速率较慢 ,可制作出具有光学镜面的侧壁〈110〉的硅模具 ,利用此模具可复制出正方形固态染料微谐振腔。以激光染料若丹明 6G掺杂的聚甲基丙烯酸甲脂 (PMMA)为工作物质 ,在调QNd∶YAG自倍频激光 5 32nm抽运下 ,得到 6 0 0nm波长的激光输出。这种谐振腔可应用在染料激光器和滤波器中 ,对其原理、设计、制作工艺和性能都作了介绍。

关键词：激光技术硅模具微细加工技术微谐振腔滤波器

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Magnetic Properties of NiCuZn Ferrite thin films Prepared by the Sol-gel Method

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Journal of Wuhan university of Technology(Materials Science) 2007年第3期22卷 506-509页

作者：刘锋 institute of Microelectronics Tsinghua University

Ni0.4Cu0.2Zn0.4Fe2O4 thin films were fabricated on Si substrates by using the sol-gel method and rapid thermal annealing （RTA）, and their magnetic properties and crystalline structures were investigated. The samples calcined at and above 600 ℃ have a single-phase spinel structure and the average grain size of the sample calcined at 600 ℃ is about 20 nm. The initial permeability μi, saturation magnetization M and coercivity H of the samples increase with the increasing calcination temperature. The sample calcined at 600 ℃ exhibits an excellent soft magnetic performance, which has μi=33.97 （10 MHz）, Hc=15.62 Oe and Ms=228.877 emu/cm^3. Low-temperature annealing can enhance the magnetic properties of the samples. The work shows that using the sol-gel method in conjunction with RTA is a promising way to fabricate integrated thin-film devices.

关键词： Ni0.4Cu0.2Zn0.4Fe2O4 thin films, sol-gel-method rapid thermal processing magnetic properties

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Radio-frequency transistors from millimeter-scale graphene domains

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Chinese Physics B 2014年第11期23卷 470-475页

作者：魏子钧傅云义刘竞博王紫东贾越辉郭剑任黎明陈远富张酣黄如张兴 institute of Microelectronics Peking University State Key Laboratory of Electronic thin films and Integrated devices University of Electronic Science and Technology of China School of Physics Peking University

Graphene is a new promising candidate for application in radio-frequency （RF） electronics due to its excellent elec- tronic properties such as ultrahigh carrier mobility, large threshold current density, and high saturation velocity. Recently, much progress has been made in the graphene-based RF field-effect transistors （RF-FETs）. Here we present for the first time the high-performance top-gated RF transistors using millimeter-scale single graphene domain on a SiO2/Si substrate through a conventional microfabrication process. A maximum cut-off frequency of 178 GHz and a peak maximum os- cillation frequency of 35 GHz are achieved in the graphene-domain-based FET with a gate length of 50 nm and 150 nm, respectively. This work shows that the millimeter-scale single graphene domain has great potential applications in RF devices and circuits.

关键词： millimeter-scale graphene domain radio-frequency transistor cut-off frequency maximum oscil-lation frequency

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Synthesis,Characterization and photocatalytic Properties of Doped Semiconducting Nano-particles

Synthesis,Characterization and Photocatalytic Properties of ...

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13th Asian Chemical Congress

作者： Wang Zegao,Jia Chunyang~* (State key Laboratory of Electronic thin films and Integrated devices university of Electronic Science and Technology of china,Chengdu,610054,P.R.china)

TiO is considered as the most attractive photocatalyst due to its high oxidative power,photostability, low cost and *** dioxide(TiO)doped with copper(Cu)and co-doped with yttrium (Y),barium(Ba)and copper(Cu)elements were prepared by a simple sol-gel *** prepared powders,which were named as Sample 1(1wt%Cu doped TiO),Sample 2(1wt%Y,Ba,Cu co-doped TiO)and Sample 3(2wt%Y,Ba,Cuco-doped TiO).

关键词： TiO2 Doping photocatalytic hydrogen photodegradation

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The L-shell ionization of Ho and Os induced by electron impact

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Chinese Science Bulletin 2006年第16期51卷 1929-1933页

作者： WU Zhangwen, GOU Chengjun, YANG Dailun, PENG Xiufeng, HE Fuqing & LUO Zhengming Key Laboratory for Radiation Physics and Technology of the Education Ministry of china institute of Nuclear Science and Technology, Sichuan university, Chengdu 610064, china Key Laboratory for Radiation Physics and Technology of the Education Ministry of china China institute of Nuclear Science and Technology Sichuan University Chengdu China

The electron-induced L-shell X-ray par- tial production cross sections, total production cross sections and mean ionization cross sections for Ho and Os have been measured as functions of electron energies from near threshold up to 36 keV by using a thin target with thick substrate technique. The influ- ence of the electrons reflected from the substrate was corrected by using the electron transport biparti- tion model. Also, the corrected measured results were compared with theoretical predictions proposed by Gryzinski and McGuire.

关键词：钬锇电子冲击电离 X射线

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Temperature dependence of the thickness and morphology of epitaxial graphene grown on SiC (0001) wafers

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Chinese Physics B 2012年第4期21卷 438-441页

作者：郝昕陈远富李萍剑王泽高刘竞博贺加瑞樊睿孙继荣张万里李言荣 State Key Laboratory of Electronic thin films and Integrated devices University of Electronic Science and Technology of ChinaChengdu 610054China Beijing National Laboratory for Condensed Matter Physics and institute of Physics Chinese Academy of SciencesBeijing 100190China

Epitaxiai graphene is synthesized by silicon sublimation from the Si-terminated 6H SiC substrate. The effects of graphitization temperature on the thickness and surface morphology of epitaxial graphene are investigated. X-ray photoelectron spectroscopy spectra and atomic force microscopy images reveal that the epitaxial graphene thickness increases and the epitaxial graphene roughness decreases with the increase in graphitization temperature. This means that the thickness and roughness of epitaxial graphene films can be modulated by varying the graphitization temperature. In addition, the electrical properties of epitaxial graphene film are also investigated by Hall effect measurement.

关键词： epitaxial graphene thickness morphology graphitization temperature

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Preparation of InSb nanocrystals embedded in SiO_2 thin films

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Chinese Science Bulletin 1998年第19期43卷 1610-1615页

作者： ZHU Kaigui 1, SHI Jianzhong 1, WEI Yanfeng 2 and ZHANG Lide 1 1. institute of Solid State Physics, Chinese Academy of Science, Hefei 230031, china 2. State Key Laboratory of Surface Physics, Fudan university, Shanghai 200433, china institute of Solid State Physics Chinese Academy of Science Hefei China State Key Laboratory of Surface Physics Fudan University Shanghai China

InSb nanocrystals embedded in SiO 2 thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed that InSb nanocrystals dispersed uniformly in SiO-2 matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of InSb nanocrystals depended on annealing temperature and time, but not on the t 1/3 rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films.

关键词： InSb nanocrystals radio-frequency sputtering quantum confinement.

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photoluminescence from Ge-SiO_2 thin films and its mechanism

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Chinese Science Bulletin 2001年第15期46卷 1268-1271页

作者： DONG Yemin, CHEN Jing, TANG Naiyun, YE Chunnuan, WU Xuemei, ZHUGE Lanjian & YAO Weiguo1. Department of Physics, Suzhou university, Suzhou 215006, china 2. Shanghai institute of Metallurgy, Chinese Academy of Sciences, Shanghai 200050, china Department of Physics Suzhou University Suzhou China Shanghai institute of Metallurgy Chinese Academy of Sciences Shanghai China

Ge-SiO2 thin films were deposited on p-type Si substrates using the radio frequency (rf) magnetron sputtering technique with a Ge-SiO2 composite target. films were annealed in N2 ambience for 30 min at 300℃-1000℃ with an interval of 100℃. Through the X-ray diffraction, the average size of Ge nanocrystals (nc-Ge) was determined. They increased from 3.9 to 6.1 nm with increasing annealing temperature in the range of 600℃-1000℃. Under ultraviolet excitation, all samples emit a strong violet band centered at 396 nm. With the formation of nc-Ge, the samples exhibit another emission of orange band with the peak at 580 nm and its intensity increases with the increasing size of *** peak positions of two bands do not shift obviously. Experimental data indicate that the violet band comes from GeO defect and the orange band originates mainly from the luminescence centers at the interface between the nc-Ge and SiO2 matrix.

关键词： Ge-SiO2 thin films rf magnetron sputtering photolumi- nescence light emitting mechanism.

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