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Azomethine ylide-formation from N-phthaloylglycine by photoinduced decarboxylation:A theoretical study

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中国科学:化学 2012年第10期42卷 1499-1500页

作者： FANG Qiu,DING LiNa & FANG WeiHai* College of chemistry,beijing Normal{2.,beijing 100875,China College of chemistry beijing Normal{2. beijing 100875 China

In this work,we report the first CASPT2./CASSCF study of the mechanism of the photodecarboxylation of *** charge transfer excited state SCT(1ππ*) is initially populated upon irradiation at 2.6 *** a result of a fast internal conversion to the lowest excited singlet state SCT-N(1ππ*),this state becomes a favorable precursor state for proton transfer,which triggers ***,the excited state intramolecular proton transfer(ESIPT) and decarboxylation processes proceed in an asynchronous concerted *** ESIPT process is accomplished in the SCT-N(1ππ*) state,but the CO2.molecule is finally formed in the ground state via the SCT/S0 conical *** ylide is formed in the ground state as a complex with CO2.A barrier of ～15 kcal/mol indicates that azomethine ylide is stable in the ground state,which is consistent with the experimental *** work provides mechanistic details about the formation of azomethine ylide by photoreaction of N-phthaloylglycine.

关键词： N-phthaloylglycine photodecarboxylation excited state intramolecular proton transfer CASPT2./CASSCF method

A systematic investigation of high harmonic generation using mid-infrared driving laser pulses

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Science China(Physics,Mechanics & Astronomy) 2010年第6期53卷 1054-1059页

作者： YAO JinPing 1,2.,XIONG Hui 1 ,XU Han 1 ,FU YuXi 1,2.,ZENG Bin 1,2.,CHU Wei 1,2.,CHENG Ya 1 ,XU ZhiZhan 1 ,LIU XiaoJun 3 & CHEN Jing 4,5 1 State Key Laboratory of High Field Laser Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 2.1800,China 2.Graduate university of Chinese Academy of Sciences,beijing 100049,China 3 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,China 4 Institute of Applied Physics and Computational Mathematics,beijing 100088,China 5 Center for Applied Physics and Technology,Peking university,beijing 100084,China State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China Graduate university of Chinese Academy of Sciences Beijing China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Institute of Applied Physics and Computational Mathematics Beijing China Center for Applied Physics and Technology Peking University Beijing China

We report on a systematic investigation of the influences of gas pressure,focal position and focusing geometry on high harmonic generation by use of mid-infrared femtosecond laser pulses. We also discuss the spatial characteristics of harmonics under different focusing conditions. By optimizing the parameters,we experimentally observed the generation of 1 kHz,low divergence coherent X-ray beams in the water-window region.

关键词： mid-infrared laser pulses high harmonic generation water window

Improvement of tribological behavior of a Ti-Al-V alloy by nitrogen ion implantation

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Rare Metals 2006年第Z1期25卷 309-314页

作者： LIU Yanzhang ZU Xiaotao QIU Shaoyu HUANG Xinquan department of Applied Physics University of Electronic Science and Technology of China Chengdu 610054 China National Key Laboratory for Nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China Department of Applied Physics University of Electronic Science and Technology of China Chengdu 610054 China National Key Laboratory for Nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China National Key Laboratory for Nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China

The tribological properties especially wear and hardness of a Ti-Al-V alloy with nitrogen implantation (energy 60 keV) were investigated. The implantation was carried out at fluences range from 1×1016 to 4×1017 ions/cm2. Glancing angle X-ray diffraction (GAXRD) and X-ray photoelectron spectroscopy (XPS) analyses were performed to obtain surface characterization of the implanted sample. The unimplanted and implanted samples were also annealed at 600 ℃ in order to understand the influence of annealing on the tribological properties of Ti-Al-V. The hardness shows significant improvement at the higher fluence. After annealing at 600 ℃, the friction coefficient exhibits a relative decrease for the nitrogen-implanted samples. In addition, the wear rates of the implanted samples exhibits a great decrease after annealing at 600 ℃. Nature of the surface and reason for the variation and improvement in wear resistance were discussed in detail.

关键词： nitrogen ion implantation Ti-Al-V alloy phase formation tribological properties

Experimental Study on Localization of Absorbers within Tissue Phantom Using a Simple Phased Array System

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Chinese Journal of Lasers 1999年第6期 3-5页

作者： LIN Fang WANG Guangzhi SU Chang DING Haishu (department of Electrical Engineering & Applied Electronics, tsinghua university,{2., China)

A simple phased array system with two anti phase near infrared (NIR) light sources whose intensities are modulated sinusoidally at 2.0 MHz is established, and experiments for exploring the light distribution in homogeneous tissue phantom (0.2.% intralipid) and the perturbations of intensity null and phase transition by absorbers are carried out. Results conform closely with the prediction by diffusion theory and the results of other groups [1,2. . Our measurements clearly demonstrate the distortion of the light distribution by the existence of absorbers and the effects on the perturbations caused by different sizes and locations of the objects. Particularly, we have studied the possibility of distinguishing between two absorbers and obtained initial results.

关键词： phased array near infrared spectroscopy diffusion theory

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各种因素对过冷水发生结冰的影响

太阳能学报 2003年第6期24卷 814-821页

作者：曲凯阳江亿清华大学建筑学院建筑技术科学系北京100084

研究外界因素对过冷水发生结冰的影响,是研究防止结冰以及制冰方法的基础。本文研究了结冰基体表面粗糙度,表面材料,表面面积,对结冰基体表面的摩擦、按压等作用,水的流动状态以及对水的磁化等对过冷水发生结冰的影响,对实验结果进行了... 详细信息

研究外界因素对过冷水发生结冰的影响,是研究防止结冰以及制冰方法的基础。本文研究了结冰基体表面粗糙度,表面材料,表面面积,对结冰基体表面的摩擦、按压等作用,水的流动状态以及对水的磁化等对过冷水发生结冰的影响,对实验结果进行了初步的理论解释,并对文献的实验结果进行了分析。

关键词：过冷水结冰发生影响因素制冰方法防止结冰

文化神经科学:一个新兴的跨学科领域(英文)

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心理科学 2011年第3期34卷 514-519页

作者：张力朱滢首都师范大学心理学系学习与认知重点实验室北京100048 北京大学心理学系北京100871

文化神经科学是一个将文化,心理与大脑整合起来的新兴的跨学科领域。本文简要地介绍了从2.00年到2.10年在文化神经科学领域内的各种观点,同时回顾了该领域里一些典型的功能性磁共振(fMRI)的研究成果。文章认为,文化神经科学可为人类心... 详细信息

文化神经科学是一个将文化,心理与大脑整合起来的新兴的跨学科领域。本文简要地介绍了从2.00年到2.10年在文化神经科学领域内的各种观点,同时回顾了该领域里一些典型的功能性磁共振(fMRI)的研究成果。文章认为,文化神经科学可为人类心理的研究提供一个全新的,整合性的理论框架,而且,它还为中国心理家提供了机遇:使用中国被试开展文化神经科学研究去取得世界一流的成果。

关键词：文化神经科学社会脑

STUDIES ON PROGRAMMING FEATURES AND METHODS OF FLOATING GATE MOSFET AS ANALOG MEMORY FOR SYNAPTIC WEIGHTS IN NEURAL NETWORKS

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Journal of Electronics(China) 1992年第4期9卷 350-352,354-357页

作者：王阳李志坚石秉学 Institute of Microelectronics Tsinghua UniversityBeijing 100084

The features of the floating gate devices as analog memory have been *** properties of the devices,compatibility and endurance of program-ming,and programming methods are presented in this *** results illustrate that thedevice can be used to store the analog weights for the neural networks,and the method that thestored value is adjusted continuously to approach to a given analog values is a rather practicalmethod for storing weights of neural networks.

关键词： Neural network Floating gate MOSFET Analog memory Synaptic weight Programming

Amplitude Squeezing of a Weakly Interacting Bose System with Spontaneous U(1) Symmetry Breaking

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Communications in Theoretical Physics 2007年第12期48卷 1047-1050页

作者： JIAO Zhi-Yong department of Applied Physics,China university of Petroleum(East China),Dongying 2.7061,ChinaYU Zhao-Xian department of Physics,beijing Information Science and Technology university,beijing 100101,ChinaWANG Ji-Suo department of Physics,Liaocheng university,Liaocheng 2.2.59,China department of Applied Physics China University of Petroleum (East China) Dongying 257061 China department of Physics Beijing Information Science and Technology University Beijing 100101 China department of Physics Liaocheng University Liaocheng 252059 China

We study the quantum fluctuations and the amplitude squeezing of a weakly interacting Bose system withspontaneous U(1) symmetry *** is found that this system can exhibit amplitude squeezing.

关键词： Bose system amplitude squeezing

Red Mechanoluminescence and Photoluminescence from Novel Europium Complexes

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Chinese Chemical Letters 2000年第7期11卷 635-638页

作者： Wei Guo ZHU Tong Suo YUAN Xiao Qiang WEI Zhi Yun LU Yan HUANG Yu LIU Qiang PENG Ming Gui XIE(department of chemistry Sichuan{2., Chengdu 610064 department of chemistry, Xiangtan{2., Xiangtan 411105 department of Biochemistry Qiongzho department of chemistry Sichuan University Chengdu 610064 China department of chemistry Xiangtan University Xiangtan 411105 China department of Biochemistry Qiongzhou University Tongshi 572200 China

Two new binuclear (europium and lanthanum) beta-diketone complexes Eu0.9La0.1(TTA)(3)Phen and Eu0.5La0.5(TTA)(3)Phen in which Phen is 1,10-phenanthroline, TTA is an anion of thenoyltrifluoroacetone (HTTA) were synthesized for the first time. They showed intense photoluminescence (PL) and mechanoluminescence (ML), and had their maximum PL and ML spectra peaked at 613.5 nm with half bandwidth of 10 nm respectively. Their PL and ML intensity were obviously stronger than these from Eu(TTA)(3)Phen. It is considered that binuclear (europium and lanthanum) beta-diketones complexes are promising ML and PL materials.

关键词： europium beta-diketone chelate synthesis mechanoluminescence (ML) photoluminescence (PL)