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Integrated optical-readout of a high-Q mechanical out-of-plane mode

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Light(Science & Applications) 2022年第10期11卷 2485-2491页

作者： jingkun guo Simon Groblacher Kavli Institute of Nanoscience Department of Quantum NanoscienceDelft University of Technology2628CJ DelftThe Netherlands

The rapid development of high-QM macroscopic mechanical resonators has enabled great advances in *** improvements could allow for quantum-limited or quantum-enhanced applications at ambient *** of the remaining challenges include the integration of high-QM structures on a chip,while simultaneously achieving large coupling strengths through an optical ***,we present a versatile fabrication method,which allows us to build fully integrated optomechanical *** place a photonic crystal cavity directly above a mechanical resonator with high-QM fundamental out-of-plane mode,separated by a small *** highly confined optical field has a large overlap with the mechanical mode,enabling strong optomechanical interaction ***,we implement a novel photonic crystal design,which allows for a very large cavity photon number,a highly important feature for optomechanical experiments and sensor *** versatile approach is not limited to our particular design but allows for integrating an out-of-plane optical read-out into almost any device ***,it can be scaled to large arrays and paves the way to realizing quantum experiments and applications with mechanical resonators based on high-QM out-of-plane modes alike.

关键词： optical resonator mode

Carbohydrate-derived porous carbon materials:An ideal platform for green organic synthesis

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Chinese Chemical Letters 2022年第1期33卷 186-196页

作者： Yamei Lin Jie Yu Xing Zhang jingkun Fang guo-Ping Lu He Huang School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityNanjing 210023China School of Pharmaceutical Sciences Nanjing Tech UniversityNanjing 210009China School of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Porous carbon materials have attracted much attention in the field of organic synthesis in recent years,due to their tunable properties,excellent catalytic activity and ***-based carbohydrates emerge as an ideal precursor for the generation of these materials owing to their renewability,low cost,non-toxicity and high content of functional ***,carbon materials prepared from carbohydrates is of considerable importance for the sustainable development of organic *** present review not only summarizes recent examples of carbohydrate-derived porous carbon material-catalyzed organic reactions including the oxidation,hydrogenation,cross-coupling,esterification and condensation reactions,but also introduces the preparation and functionalization strategies of these ***,the challenges and opportunities of organic synthesis over these sustainable materials have also been *** review will stimulate further research on exploring novel carbohydrate-derived porous carbon materials and new sustainable organic synthetic processes over these materials.

关键词： Carbohydrates Carbon materials Green chemistry Catalysis Organic synthesis

Trapping and Driving Individual Charged Micro-particles in Fluid with an Electrostatic Device

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Nano-Micro Letters 2016年第3期8卷 270-281页

作者： Jingjing Xu Zijing Lei jingkun guo Jie Huang Wei Wang Uta Reibetanz Shengyong Xu Key Laboratory for the Physics & Chemistry of Nanodevices and Department of Electronics Peking University Institute of Microelectronics Peking University Medical Faculty Institute for Medical Physics and Biophysics University of Leipzig

A variety of micro-tweezers techniques, such as optical tweezers, magnetic tweezers, and dielectrophoresis technique, have been applied intensively in precise characterization of micro/nanoparticles and bio-molecules. They have contributed remarkably in better understanding of working mechanisms of individual sub-cell organelles, proteins, and DNA. In this paper, we present a controllable electrostatic device embedded in a microchannel, which is capable of driving,trapping, and releasing charged micro-particles suspended in microfluid, demonstrating the basic concepts of electrostatic tweezers. Such a device is scalable to smaller size and offers an alternative to currently used micro-tweezers for application in sorting, selecting, manipulating, and analyzing individual micro/nanoparticles. Furthermore, the system offers the potential in being combined with dielectrophoresis and other techniques to create hybrid micro-manipulation systems.

关键词： Electrostatic tweezers Charged particles Coulomb potential well Manipulation Trap

Bone morphogenetic protein 4 induces cholinergic differentiation of brain-derived neural stem cells in vivo and in vitro

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Neural Regeneration Research 2010年第21期5卷 1611-1616页

作者： Yan Chang jingkun Pan Lei Tian Shuilong guo Yun Luo Xin Cui Yilong Xue Laboratory of Cell Biology Institute of Geriatrics General Hospital of Chinese PLA Beijing 100853 China

In vitro studies have demonstrated that many factors of bone morphogenetic proteins （BMPs） induce cholinergic differentiation of neural stem cells. However, BMP retains the potential to induce increased numbers of cholinergic neurons in central nervous system regions that are rich in cholinergic cells, which is an important determinant of BMP. Therefore, BMP-4 was added to neural stem cell culture medium or the adult rat hippocampal dentate gyrus. Results demonstrated that BMP-4 induced cholinergic differentiation of neural stem cells in vitro and increased the number of cholinergic neurons in the adult rat hippocampal dentate gyrus.

关键词： bone morphogenetic protein neural stem cell induced differentiation cholinergic neuron neural regeneration

Solid-state-reaction fabrication and properties of a high-doping Nd:YAG transparent laser ceramic

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Frontiers of Chemical Science and Engineering 2008年第3期2卷 248-252页

作者： Jiang LI Yusong WU Yubai PAN Wenbin LIU Liqiong AN Shiwei WANG jingkun guo Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China Graduate School of the Chinese Academy of Sciences Beijing 10039China

High-quality neodymium-doped yttrium aluminum garnet(Nd:YAG)transparent ceramic(4.0 mole percent)was fabricated by a solid-state reaction method and vacuum *** microstructure,optical transmittance,spectral properties and laser performance were *** average grain size of the sample is about 10 *** transmittance of a 2.8-mm thick sample reaches 79.5%at the laser wavelength of 1064 *** highest absorption peak is centered at 807 nm and the absorption coefficient is 13.9 cm^(-1).The absorption coefficient at the laser wavelength is 0.2 cm^(-1).The main emission peak is at 1064 nm and the fluorescence lifetime is 102 ms.A laser diode(808 nm)whose maximum output is about 1000 mW was used as a pump source and an endpumped laser experiment was *** 1064 nm-CW-laser output was obtained and the threshold is 733 *** 998 mW of maximum absorbed pump power,a laser output of 17 mW is obtained with a slope efficiency of 6.1%.

关键词： transparent laser ceramic optical properties microstructure high-doping concentration solid state reaction

纳米SiC及Si_3N_4/SiC的高温等静压研究

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无机材料学报 1997年第2期12卷 191-194页

作者：董绍明江东亮谭寿洪郭景坤中国科学院上海硅酸盐研究所上海200050

采用高温等静压（HIP）工艺，制备了纳米结构的单相SiC及Si3N4／SiC复相陶瓷，并通过X射线衍射分析、透射及高分辨电镜对其相组成及结构进行了表征．实验表明，在温度1850℃、压力200MPa条件下保温lh，可获得晶粒尺寸＜100nm、结构均匀... 详细信息

采用高温等静压（HIP）工艺，制备了纳米结构的单相SiC及Si3N4／SiC复相陶瓷，并通过X射线衍射分析、透射及高分辨电镜对其相组成及结构进行了表征．实验表明，在温度1850℃、压力200MPa条件下保温lh，可获得晶粒尺寸＜100nm、结构均匀、致密的单相SiC纳米结构陶瓷．对于St3N4／SiC复相体系，初始粉末的结晶形态对烧结体的结构有很大的影响.将初始粉末进行预处理后：在温度1750℃、压力150MPa条件下保温1h，可获得晶粒尺寸在50nm左右、结构致密、均匀的复相Si3N4／SiC纳米陶瓷材料．

关键词：纳米陶瓷高温等静压陶瓷压制成型碳化硅陶瓷

Two-step preparation of carbon nanotubes/Ru02/polyindole ternary nanocomposites and their application as high-performance supercapacitors

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Frontiers of Materials Science 2020年第2期14卷 109-119页

作者： Danhua ZHU Qianjie ZHOU Aiqin LIANG Weiqiang ZHOU Yanan CHANG Danqin LI Jing WU guo YE jingkun XU Yong REN Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Department of Mathematical Sciences Zibo Normal CollegeZibo 255130China

A ternary single-walled carbon nanotubes/RuO2/polyindole(SWCNT/RuO2/PIn)nanocomposite was fabricated by the oxidation polymerization of indole on the prefabricated SWCNT/RuO2 binary *** nanocomposite was measured by FTIR,XRD,SEM,TEM,EDS and XPS,together with the electrochemical *** electrochemical results demonstrated that the symmetric supercapacitor used SWCNT/RuO2/PIn as electrodes presented 95%retention rate after 10000 cycles,superior capacitive performance of1203 F·g^-1 at1 A·g^-1,and high energy density of 33 w h·kg^-1 at 5000 W·kg^-*** high capacitance performance of SWCNT/RuO2/PIn nanocomposite was mainly ascribed to the beneficial cooperation effect among *** indicated that the SWCNT/RuO2/PIn nanocomposite would be a good candidate for high-performance supercapacitors.

关键词： SWCNT/RuO2/PIn nanocomposite supercapacitor

层状Al_2O_3-TiC复相陶瓷的制备与性能

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无机材料学报 1997年第6期12卷 802-808页

作者：曾宇平江东亮谭寿洪郭景坤中国科学院上海硅酸盐研究所上海200050

利用流延成型工艺制备了Al_2O_3－TiC复相陶瓷薄膜．通过叠层、预压、脱粘和热压烧结工艺，制备了层状结构复相陶瓷．讨论了分散剂、pH值、固含量对浆料粘度的影响．用TGA分析了陶瓷膜的脱粘过程．用SEM和光学显微镜分析了素坯膜的微观... 详细信息

利用流延成型工艺制备了Al_2O_3－TiC复相陶瓷薄膜．通过叠层、预压、脱粘和热压烧结工艺，制备了层状结构复相陶瓷．讨论了分散剂、pH值、固含量对浆料粘度的影响．用TGA分析了陶瓷膜的脱粘过程．用SEM和光学显微镜分析了素坯膜的微观形貌和材料在压应力作用下裂纹扩展情况．由于裂纹沿弱界面扩展使应力松弛，有效地提高了材料的断裂韧性和断裂功。

关键词：流延成型断裂复合陶瓷层状氧化铝碳化钛

Morphological characteristics of α-Al_2O_3 crystallites obtained directly from hydro/solvothermal solvents

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Chinese Science Bulletin 1998年第2期43卷 163-166页

作者： WANG Buguo, TIAN Mingyuan, SHI Erwei, ZHONG Weizhuoand guo jingkun Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201800, China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China

The morphological characteristics of α_Al-2O-3 crystallites obtained directly from hydro/solv othermal solvents are reported and the formation mechanisms of corundum morphology are discussed from crystal growth and crystal chemistry principles. The crystal growth process is considered as a process of incorporation of growth units on the growth interfaces, and the crystal morphology is determined by the linkage of the coordinated polyhedra.

关键词： hydrothermal crystallization α_Al-2O-3 crystallites morphology growth mechanisms.