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941.
Carbonyl compounds containing electron-withdrawing substituents are efficiently oxidized by aqueous sodium hypochlorite in the absence of added organic solvents using microwaves. 相似文献
942.
S. Nasu T. Sato S. X. Nakamura K. Sumiyoshi F. Myhrer K. Kubodera 《Few-Body Systems》2013,54(7-10):1595-1598
We have investigated the neutrino reactions via deuteron in the surface region of the supernova core. We evaluate the electron capture on deuterons and the neutrino emission from nucleon-nucleon scattering through the deuteron formation and found an important role of neutrino reactions with deuteron. 相似文献
943.
本文基于第一性原理方法研究了Y,Zr,Nb在Sn位掺杂SnO_2的键长变化、稳定性、能带结构以及态密度.结果表明:Y,Zr,Nb在Sn位掺杂SnO_2使附近的键长发生改变,改变量最大是Y掺杂SnO_2体系;掺杂体系的杂质替换能都为负值,表明体系为稳定结构;掺杂使SnO_2能级增多,能较好的调节带隙值;而Y掺杂SnO_2体系价带顶端有一条能级越过了费米线表明该体系呈现出半导体的特征;同时,Y,Zr,Nb掺杂SnO_2使导带底端的能级出现分离;在低能区的态密度仍主要由Sn、O的s轨道贡献;在高能区态密度的掺杂体系出现sp杂化的现象; Zr掺杂SnO_2的态密度能量向低能区移动. 相似文献
944.
Manqi Ruan Hang Zhao Gang Li Chengdong Fu Zhigang Wang Xinchou Lou Dan Yu Vincent Boudry Henri Videau Vladislav Balagura Jean-Claude Brient Peizhu Lai Chia-Ming Kuo Bo Liu Fenfen An Chunhui Chen Soeren Prell Bo Li Imad Laketineh 《The European Physical Journal C - Particles and Fields》2018,78(5):426
After the Higgs discovery, precise measurements of the Higgs properties and the electroweak observables become vital for the experimental particle physics. A powerful Higgs/Z factory, the Circular Electron Positron Collider (CEPC) is proposed. The Particle Flow oriented detector design is proposed to the CEPC and a Particle Flow algorithm, Arbor is optimized accordingly. We summarize the physics object reconstruction performance of the Particle Flow oriented detector design with Arbor algorithm and conclude that this combination fulfills the physics requirement of CEPC. 相似文献
945.
In this work we present an optical lattice setup to realize a full Dirac Hamiltonian in 2+1 dimensions. We show how all possible external potentials coupled to the Dirac field can arise from perturbations of the existing couplings of the honeycomb lattice pattern. This greatly simplifies the proposed implementations, requiring only spatial modulations of the intensity of the laser beams to induce complex non-Abelian potentials. We finally suggest several experiments to observe the properties of the quantum field theory in the setup. 相似文献
946.
Zhong‐Fu An Chao Zheng Dr. Run‐Feng Chen Jun Yin Jian‐Jian Xiao Hui‐Fang Shi Ye Tao Dr. Yan Qian Prof. Wei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15655-15661
A novel conjugated asymmetric donor–acceptor (CADA) strategy for preventing the redshift in photoluminescence, as well as preserving the merits of donor–acceptor architectures, was proposed and demonstrated for two triazine derivatives, which showed highly efficient, narrow, and blueshifted ultraviolet light emission in solid films along with special aggregation‐induced emission behavior. A mechanism of aggregation‐induced locally excited‐state emission by suppressing the twisted intramolecular charge‐transfer emission for the spectacular optoelectronic phenomena of these CADA molecules was suggested on the basis of both experimental measurements and theoretical calculations. By taking advantage of this special CADA architecture, fluorescent probes based on aggregates of conjugated asymmetric triazines in THF/water for the detection of explosives show superamplified detection of picric acid with high quenching constants (>1.0×107 M ?1) and a low detection limit of 15 ppb. 相似文献
947.
948.
949.
X. Hernandez M. A. Jiménez C. Allen 《The European Physical Journal C - Particles and Fields》2012,72(2):1884
Modified gravity scenarios where a change of regime appears at acceleration scales a<a
0 have been proposed. Since for 1M
⊙ systems the acceleration drops below a
0 at scales of around 7000 AU, a statistical survey of wide binaries with relative velocities and separations reaching 104 AU and beyond should prove useful to the above debate. We apply the proposed test to the best currently available data. Results
show a constant upper limit to the relative velocities in wide binaries which is independent of separation for over three
orders of magnitude, in analogy with galactic flat rotation curves in the same a<a
0 acceleration regime. Our results are suggestive of a breakdown of Kepler’s third law beyond a≈a
0 scales, in accordance with generic predictions of modified gravity theories designed not to require any dark matter at galactic
scales and beyond. 相似文献
950.