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991.
992.
Yao Chengli Zhu Jinmiao Li Hongying Zheng Bin Wei Yanxin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(13):2680-2685
Russian Journal of Physical Chemistry A - Zinc oxide (ZnO) nanostructured materials have received significant attention because of their unique physicochemical and electronic properties. In... 相似文献
993.
QIN Qing HUANG Nan LIU Wei-Bin LIU Yu-Dong PENG Yue-Mei QIU Jing WANG Dou WANG Xin-Hao WANG Na WANG Jiu-Qing WEI Yuan-Yuan WEN Xue-Mei XING Jun XU Gang Yu Cheng-Hui ZHANG Chuang ZHANG Yuan ZHAO Zheng ZHOU De-Min 《中国物理C(英文版)》2009,33(Z2)
During the 1st and 2nd stages of the commissioning of the upgrade project of the Beijing Electron Positron Collider(BEPC Ⅱ),which started on Nov.12,2006 and Oct.24,2007,respectively,we got the luminosity one tenth of its design value,provided beams to synchrotron radiation users for about 4 months,and studied beam dynamics as well.In this paper,some beam dynamics studies on the storage rings and their preliminary results are given. 相似文献
994.
A novel plasmonic nanolens formed by a tapered subwavelength metal slit surrounded by surface dielectric gratings is proposed and demonstrated numerically. By patterning surface corrugations on the output surface, the beam can be focused, by regulating the aperture, the focal length can be controlled effectively. Numerical simulations using Finite-Difference Time-Domain (FDTD) method coupled with anisotropic perfectly matched layer (APML) boundary conditions verify that the proposed metallic lens can focus the radiation on the scale of a wavelength below the substrate and the method is effective for the design of nano-optical devices such as optical microprobes. 相似文献
995.
Three new compounds, 2‐methoxy‐3,4‐(methylenedioxy)benzophenone ( 1 ), 4‐hydroxy‐2,3‐dimethoxybenzophenone ( 2 ), and 3‐hydroxy‐4,6‐dimethoxy‐9H‐xanthen‐9‐one ( 3 ), besides three known compounds were isolated from the roots of Securidaca inappendiculata. Their structures were established by spectroscopic means and X‐ray crystallographic diffraction analysis. The biogenetic relationships among these six compounds are discussed. 相似文献
996.
997.
In this work, a column-like nano/micro-scale topography surface has been prepared via trichloro(octyl)silane (TCOS) vapor deposition on the air plasma oxidized polydimethylsiloxane (PDMSOx) surface. TCOS was mixed into n-heptyl alcohol and dimethyl-silicone oil to form a series of mixture. TCOS could anchor to the PDMSOx surface to form column-like nano/micro-scale topography while n-heptyl alcohol and TCOS volatilized to the PDMSOx surface in the subsequent vapor phase process. These surfaces were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared-attenuated total reflection, contact angle measuring system and atomic force microscopy. It was shown that TCOS had been successfully assembled on the polydimethylsiloxane surface. N-heptyl alcohol mixed into alkylsiloxane could regulate the scale and roughness of column-like nano/micro-scale topography. 相似文献
998.
Yemin Hu Zheng Hu Leshu Yu Ying Li Mingyuan Zhu Qin Bai 《Applied Physics A: Materials Science & Processing》2011,103(1):67-72
Large-area comb-like chromium disilicide (CrSi2) nanowire film has been successfully synthesized on silicon wafer through an in situ chloride-generated route. The sample
possesses branch-like nanowires grown out perpendicularly and evenly from both sides of a stem-like microrod, forming 2-fold
comb-like hierarchical nanoarchitectures. The formation mechanism of the sample could be understood by a secondary nucleation
process occurring on the surface of the firstly formed CrSi2 microrod, followed by epitaxial growth of branch-like nanowires under conditions of proper temperature and sufficient vapor
supply in the reaction system. The field-emission behavior of the sample shows a low turn-on field of 5.3–6.5 V/μm at anode-sample
distances of 200–400 μm, and agrees well with the conventional Fowler–Nordheim theory. No obvious degradation was observed
in a life stability experiment period for over 100 min. The relationship between the field enhancement factor and anode-sample
distance follows a universal equation, developed within a two-region field-emission model. The convenient and low-cost preparation
of the comb-like CrSi2 nanowires and their remarkable field-emission performance suggest that they can serve as good candidates for field-emission
applications. 相似文献
999.
1000.
Wen-Jun Liang Hong-Ping Fang Jian Li Feng Zheng Jing-Xin Li Yu-Quan Jin 《Journal of Electrostatics》2011,69(3):206-213
Destruction of hydrogen sulfide using dielectric barrier discharge plasma in a coaxial cylindrical reactor was carried out at atmospheric pressure and room temperature. Three types of DBD reactor were compared in terms of specific energy density (SED), equivalent capacitances of the gap (Cg) and the dielectric barrier (Cd), energy yield (EY), and H2S decomposition. In addition, byproducts during the decomposition of H2S and destruction mechanism were also investigated. SED for all the reactors depended almost linearly on the voltage. In general, Cg decreased with increasing voltage and with the existence of pellet material, while Cd displayed the opposite trend. The removal efficiency of H2S increased substantially with increasing AC frequency and applied voltage. Longer gas residence times also contributed to higher H2S removal efficiency. The choice of pellet material was an important factor influencing the H2S removal. The reactor filled with ceramic Raschig rings had the best H2S removal performance, with an EY of 7.30 g/kWh. The likely main products in the outlet effluent were H2O, SO2, and SO3. 相似文献