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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth Sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3 & DENG Jun1 1 state key {2. of Geological Processes and Mineral Resources,china university of Geosciences,Beijing100083,china 2.{2. of nuclear Analysis Techniques,Institute of High Energy physics,Chinese Academy of Sciences,Beijing 100039,china 3 Department of Geology,peking university,Beijing {12.,china 1. state key {2. of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―350℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132.Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

β-delayed proton decays near the proton drip line

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3 , WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. {2. physics Department, china Institute of Atomic Energy, Beijing 102.13, china 3. Department of Technical physics, peking university, Beijing 100871, china 4. Shanghai Institute for {2. Research, Shanghai 2.1800, china 1. Institute of Modern physics Chinese Academy of Sciences 730000 Lanzhou China 2. nuclear physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical physics Peking University 100871 Beijing China 4. Shanghai Institute for nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93Pd are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142.o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3) The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Phase reaction of Au/Sn solder bonding for GaN-based vertical structure light emitting diodes

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Science china(Technological Sciences) 2010年第2期53卷 301-305页

作者： TIAN PengFei, SUN YongJian, CHEN ZhiZhong, QI ShengLi, DENG JunJing, YU TongJun, QIN ZhiXin & ZHANG GuoYi state key {2. for Artificial Microstructure and Mesoscopic physics, school of physics, peking university, Beijing 100871, china 1. state key {2. for Artificial Microstructure and Mesoscopic physics School of Physics Peking University Beijing 100871 China

Au/Sn solder bonding on Si substrates was used to fabricate the GaN-based vertical structure light emitting diodes (VSLEDs). The phase reaction of Au/Sn solder under different bonding conditions was investigated by the measurement of electron back scattering diffraction (EBSD), and the characteristics of VSLED were analyzed by scanning acoustic microscope (SAM), Raman scattering, current-voltage (I-V) and light output-current (L-I) curves. After the bonding process, horizontal stripes of Au/Sn phase (δ phase) and Au5Sn phase (ζ phase) were redirected to vertical stripes, and δ phase tended to move to the solder joint. Sn interstitial diffusion led to the distribution of δ phase and voids in Au/Sn solder, which could be seen in SAM and SEM images. Vertical distribution of the δ phase and ζ phase with proper voids in the Au/Sn bonding layer showed the best bonding quality. Good bonding quality led to little shift of the E2.high mode of Raman spectra peak in GaN after laser lift off (LLO). It also caused more light extraction and forward bias reduction to 2.9 V at 2. mA.

关键词： GaN LED bonding Au/Sn phase

An electrically tunable metasurface integrated with graphene for mid-infrared light modulation

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Chinese physics B 2017年第11期26卷 180-185页

作者：王宗鹏邓娅孙连峰 state key {2. for Mesoscopic physics School of Physics Peking University National Center for Nanoscience and technology

We propose a low-cost plasmonic metasurface integrated with single-layer graphene for dynamic modulation of midinfrared light. The plasmonic metasurface is composed of an array of split magnetic resonators（MRs） where a nano slit is included. Extraordinary optical transmission（EOT） through the deep subwavelength slit is observed by excitation of magnetic plasmons in the split MRs. Furthermore, the introduction of the slit provides strongly enhanced fields around the graphene layer, leading to a large tuning effect on the EOT by changing the Fermi energy of the graphene. The proposed metasurface can be utilized as an optical modulator with a broad modulation width（15 μm） or an optical switch with a high on/off ratio（〉 100）. Meanwhile, the overall thickness of the metasurface is 430 nm, which is tens of times smaller than the operating wavelength. This work may have potential applications in mid-infrared optoelectrical devices and give insights into reconfigurable flat optics and optoelectronics.

关键词： metasurface graphene optical modulator magnetic plasmon

Application of cathodoluminescence to zircon in FEG-ESEM

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Progress in Natural Science:Materials International 2006年第9期16卷 919-924页

作者： CHEN Li , XU Jun and SU Li (Electron Microscopy laboratory, school of physics,{2., Beijing 100871, china Geology Experimental Center, china university of Geoscience, Beijing 100083, china) Electron Microscopy laboratory School of Physics Peking University Beijing 100871 China Geology Experimental Center China University of Geoscience Beijing 100083 China

Cathodoluminescence (CL) image analysis of zircon is a key step of mineral micro-area compositional investigation and U-(Th)-Pb dating. We introduce a system consisting of field emission ESEM and high performance cathodoluminescence. This system has obvious advantages in imaging resolution and CL spectrum. We acquired some zircon CL images and spectra to demonstrate the ability of this system. Our results show that this system has a great potential application to characterize and identify the genesis of zircon.

关键词： zircon cathodoluminescence ESEM.

Exact Periodic-Wave Solutions for(2.1)-Dimensional Boussinesq Equation and (3+1)-Dimensional KP Equation

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Communications in Theoretical physics 2004年第8期42卷 239-241页

作者： ZHAO Qiang LIU Shi-Kuo FU Zun-Tao school of physics, peking university, Beijing {2., china school of physics Peking University Beijing 100871 China

The(2.1)-dimensional Boussinesq equation and(3+1)-dimensional KP equation are studied by using theextended Jacobi elliptic-function *** exact periodic-wave solutions for the two equations are obtained.

关键词： Jacobi elliptic-function method (2.l)-dimensional Boussinesq equation (3+l)-dimensional KP equation periodic-wave solutions

A SQP optimization method for shimming a permanent MRI magnet

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Progress in Natural Science:Materials International 2009年第10期19卷 1439-1443页

作者： Zhe Jina,Xing Tangb,Bin Menga,Donglin Zu b,Weimin Wanga,a Institute of Quantum Electronics,school of Electronics Engineering and Computer Science,peking {2.,Beijing 100871,china b Institute of Heavy Ion physics,Beijing key laboratory of Medical physics and Engineering,school of physics,peking {2.,Beijing 100871,china [a]Institute of Quantum Electronics School of Electronics Engineering and Computer Science Peking University Beijing 100871 China [b]Institute of Heavy Ion physics Beijing Key Laboratory of Medical Physics and Engineering School of Physics Peking University Beijing 100871 China

Based on the sequential quadratic programming(SQP) method,a new approach is presented in this paper to gain a uniform magnetic field for a permanent MRI magnet with biplanar ***,the adopted shimming piece is modeled as a magnetic dipole moment to calculate its effect on the background field over the imaging region of ***,the SQP method is utilized to determine the ideal solution for the shimming ***,the ideal solution is discrete,and the quantization error control technique is used for special *** new method helps to reduce the inhomogeneity from 12.4.5 ppm to 2..4 ppm over a 36 cm diameter spherical volume(DSV),within hours in practical shimming work.

关键词： Magnetic resonance imaging(MRI) Field shimming Sequential quadratic programming(SQP) Permanent MRI magnet

The size effect on transport properties of colossal magnetoresistance materials La_(0.67)Ca_(0.33)MnO_3

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Science china(physics,Mechanics & Astronomy) 2008年第3期51卷 251-257页

作者： LI PeiGang1,2.LEI Ming1,2.GUO YanFeng2.GUO Xi2.CHEN LeiMing2. TANG WeiHua1,2.SONG PengYun3 & CHEN JinPing3 1 Department of physics,Center for Optoelectronics Materials and Devices,Zhejiang Sci-Tech university,Hangzhou 310018,{2. 2.National laboratory for Condensed Matter physics,Institute of physics,Chinese Academy of Sciences,Beijing 100080,{2. 3 Department of physics,peking university,Beijing 100875,{2. 1. Department of physics Center for Optoelectronics Materials and Devices Zhejiang Sci-Tech University Hangzhou 310018 China 2. National laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 3. Department of physics Peking University Beijing 100875 China

High quality La0.67Ca0.33MnO3 (LCMO) film was deposited via a novel pulsed electron deposition technique on SrTiO3(100) single crystal substrate. The micro-bridge with different widths was fabricated by using electron beam lithography (EBL) technique and their transport properties were studied. For the micro-bridges with width of 2.and 1.5 μm,the insulator-to-metal transition temperature (TP) keeps un-changed compared with the film. For the micro-bridges with width of 1 μm,the TP shifts towards the lower temperature by 50 K. When the width decreases down to 500 nm,the insulator-to-metal transition disappears. The magnetoresistance be-havior of these micro-bridges was studied,and the results show that the low field magnetoresistance (LFMR) decreases and the high field magnetoresistances (HFMR) keep almost unchanged as the width of micro-bridge is reduced.

关键词： colossal magnetoresistance pulsed electron deposition electron beam lithography electrical transport properties

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1 & TAN Wenchang2.1. Institute of Applied Mathematics, school of Math & System Science, Shandong university, Jinan 2.0100,{2. 2. state key laboratory of Turbulence and Complex Systems & Department of Mechanics and Engineering Science, peking university, Beijing 100871,{2. 1. Institute of Applied Mathematics School of Math & System Science Shandong University Jinan 250100 China 2. state key {2. of Turbulence and Complex Systems & Department of Mechanics and Engineering Science Peking University Beijing 100871 China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics