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991.
ZHAI Shuo HONG HaiYan ZHOU YongFeng & YAN DeYue State Key Laboratory of Metal Matrix Composites College of Chemistry Chemical Engineering Shanghai Jiao Tong University Shanghai China 《中国科学:化学》2010,(5)
A novel hyperbranched multiarm copolymer of HBPO-star-PDEAEMA with a hydrophobic poly(3-ethyl-3-(hydroxymethyl) oxetane)(HBPO) core and many cationic poly(2-(N,N-diethylamino) ethyl methacrylate)(PDEAEMA) arms has been synthesized through an atom transfer radical polymerization(ATRP) method,and been applied to spontaneously reduce and stabilize gold nanoparticles(AuNPs) in water without other additional agents.The size of the nanoparticles could be effectively controlled at about 4 nm,and the nanoparticles ... 相似文献
992.
Thermodynamic analysis of the theoretical energy consumption in the removal of organic contaminants by physical methods
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JI YuanHui LU XiaoHua YANG ZhuHong & FENG Xin State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing University of Technology Nanjing China 《中国科学:化学》2010,(3)
The essential requirements for evaluating the sustainable development of a system and the thermodynamic framework of the energy conservation mechanism in the waste-removal process are proposed.A thermodynamic method of analysis based on the first and second laws of thermodynamics is suggested as a means to analyze the theoretical energy consumption for the removal of organic contaminants by physical methods.Moreover,the theoretical energy consumption for the removal by physical methods of different kinds of... 相似文献
993.
R. Bailhache A. Andronic P. Braun-Munzinger for the ALICE Collaboration 《Indian Journal of Physics》2010,84(12):1695-1700
The possibility to detect the Z0 in the ALICE central barrel is studied via the electronic decay channel Z0 → e
+
e
−. The signal and the background are simulated with the leading order event generator PYTHIA 6. The total cross-sections are
taken from NLO calculations. Based on test beam data, the electron identification performance of the Transition Radiation
Detector is extrapolated to high momenta. The expected yields for minimumbias pp collisions at 14TeV are presented. An isolation cut on the single electron, together with a minimum transverse momentum cut,
allows to obtain a clear signal. The expected background is of the order of 1% with the main contribution coming from misidentified
pions from jets. 相似文献
994.
For a set Ω of size n≥7 and Ω{3} the set of subsets of Ω of size 3, we examine the ternary codes obtained from the adjacency matrix of each of the three graphs with vertex set Ω{3}, with adjacency defined by two vertices as 3-sets being adjacent if they have zero, one or two elements in common, respectively. 相似文献
995.
PARALLEL AUXILIARY SPACE AMG FOR H(curl) PROBLEMS 总被引:2,自引:0,他引:2
In this paper we review a number of auxiliary space based preconditioners for the second order definite and semi-definite Maxwell problems discretized with the lowest order Nedelec finite elements. We discuss the parallel implementation of the most promising of these methods, the ones derived from the recent Hiptmair-Xu (HX) auxiliary space decomposition [Hiptmair and Xu, SIAM J. Numer. Anal., 45 (2007), pp. 2483-2509]. An extensive set of numerical experiments demonstrate the scalability of our implementation on large-scale H(curl) problems. 相似文献
996.
Mackinnon AJ Patel PK Borghesi M Clarke RC Freeman RR Habara H Hatchett SP Hey D Hicks DG Kar S Key MH King JA Lancaster K Neely D Nikkro A Norreys PA Notley MM Phillips TW Romagnani L Snavely RA Stephens RB Town RP 《Physical review letters》2006,97(4):045001
Protons accelerated by a picosecond laser pulse have been used to radiograph a 500 microm diameter capsule, imploded with 300 J of laser light in 6 symmetrically incident beams of wavelength 1.054 microm and pulse length 1 ns. Point projection proton backlighting was used to characterize the density gradients at discrete times through the implosion. Asymmetries were diagnosed both during the early and stagnation stages of the implosion. Comparison with analytic scattering theory and simple Monte Carlo simulations were consistent with a 3+/-1 g/cm3 core with diameter 85+/-10 microm. Scaling simulations show that protons>50 MeV are required to diagnose asymmetry in ignition scale conditions. 相似文献
997.
ZHUANG MuDe LIU Zheng REN Bin & TIAN ZhongQun State Key Laboratory of Physical Chemistry of Solid Surfaces 《中国科学:化学》2010,(2)
Tip-enhanced Raman spectroscopy (TERS) has been used to obtain the Raman signal of surface species on silicon single crystal surfaces without the necessity for surface enhancement by addition of Ag nanoparticles. By illuminating the hydrogen terminated silicon surface covered with a droplet of 4-vinylpyridine with UV light, a 4-ethylpyridine modified silicon surface can be easily obtained. By bringing a scanning tunneling microscope (STM) Au tip with a nanoscale tip apex to a distance of ca. 1 nm from the m... 相似文献
998.
JIA MingLi WAN Yan WANG XueFei & XIA ong State Key Laboratory of Molecular Reaction Dynamics Beijing National Laboratory for Molecular Sciences 《中国科学:化学》2010,(2)
Photoinduced electron transfer (ET) between C60 and porphyrin (P) in a new polymer containing porphyrin, poly(p-phenyle nevinylene), and pendant fullerene units has been investigated by nanosecond transient absorption and phosphorescence spectroscopy. Compared to the physically doping material systems, binding porphyrin/C60 through chemical bonds in a polymer detains the formation of the triplet states of porphyrins and C60. The formation of intermediate charge transfer state (CSS) of P·+-C60·? was observed... 相似文献
999.
YANG Fan LIU YuWen OU LiHui WANG Xin & CHEN ShengLi Hubei Electrochemical Power Sources Key Laboratory 《中国科学:化学》2010,(2)
A density functional theory (DFT)-calculation scheme for constructing the modified embedded atom method (MEAM) potentials for face-centered cubic (fcc) metals is presented. The input quantities are carefully selected and a more reliable DFT approach for surface energy determination is introduced in the parameterization scheme, enabling MEAM to precisely predict the surface and nanoscale properties of metallic materials. Molecular dynamics simulations on Pt and Au crystals show that the parameterization empl... 相似文献
1000.
XIAO TieJun & HOU ZhongHuai Hefei National Laboratory for Physical Sciences at the Microscale 《中国科学:化学》2010,(2)
Fluctuation theorem for entropy production in a mesoscopic chemical reaction network is discussed. When the system size is sufficiently large, it is found that, by defining a kind of coarse-grained dissipation function, the entropy production in a reversible reaction channel can be approximately described by a type of detailed fluctuation theorem. Such a fluctuation relation has been successfully tested by direct simulations in a linear reaction model consisting of two reversible channels and in an oscillat... 相似文献