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Experimental Study of the Influence of Process Pressure and Gas Composition on GaAs Etching Characteristics in Cl_2/BCl_3-Based Inductively Coupled Plasma

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Plasma Science and Technology 2011年第2期13卷 223-229页

作者： D.S.RAWAL B.K.SEhGAL R.mURALIDhARAN h.K.mALIK Solid State Physics Laboratory PWAPA Laboratory Department of Physics Indian Institute of Technology Delhi

A study of Cl2/BCl3-based inductively coupled plasma （ICP） was conducted using thick photoresist mask for anisotropic etching of 50μm diameter holes in a GaAs wafer at a relatively high average etching rate for etching depths of more than 150μm. Plasma etch characteristics with ICP process pressure and the percentage of BCI3 were studied in greater detail at a constant ICP coil/bias power. The measured peak-to-peak voltage as a function of pressure was used to estimate the minimum energy of the ions bombarding the substrate. The process pressure was found to have a substantial influence on the energy of heavy ions. Various ion species in plasma showed minimum energy variation from 1.85 eV to 7.5 eV in the pressure range of 20 mTorr to 50 mTorr. The effect of pressure and the percentage of BCl3 on the etching rate and surface smoothness of the bottom surface of the etched hole were studied for a fixed total flow rate. The etching rate was found to decrease with the percentage of BCl3, whereas the addition of BCl3 resulted in anisotropic holes with a smooth veil free bottom surface at a pressure of 30 mTorr and 42% BC13. In addition, variation of the etching yield with pressure and etching depth were also investigated.

关键词： GaAs inductively coupled plasma etching ion energy etch yield

中试规模下蜂窝式mn-Ce/Al2O3脱硝催化剂的低温性能

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环境工程学报 2018年第4期12卷 1055-1064页

作者：王成志曹鹏颜鑫孔伟石河子大学化学化工学院新疆兵团化工绿色过程重点实验室石河子832003 石河子天富南热电有限公司石河子832000

采用自行设计的反应装置,研究中试规模条件下关键参数对蜂窝堇青石mn-Ce/Al_2O_3催化剂脱硝效率的影响以及抗硫抗水性能,并通过扫描电子显微镜(SEm)、能谱仪(EDS)、X射线衍射(XRD)和比表面积测试仪(BET)研究催化剂的理化性质。结果表明... 详细信息

采用自行设计的反应装置,研究中试规模条件下关键参数对蜂窝堇青石mn-Ce/Al_2O_3催化剂脱硝效率的影响以及抗硫抗水性能,并通过扫描电子显微镜(SEm)、能谱仪(EDS)、X射线衍射(XRD)和比表面积测试仪(BET)研究催化剂的理化性质。结果表明,反应温度、空速、氨氮比对催化活性均有明显影响,同时,催化剂对氮氧化物浓度有较强适应性,NO浓度在134～469mg·m^(-3)区间内脱硝效率均可保持在75%以上。催化剂在100℃,空速3 336h^(-1),[Nh_3]/[NO]为0.9,烟气量20m^3·h^(-1)条件下连续反应168h,其催化效率可以稳定保持在75%～80%,说明蜂窝式mn-Ce/Al_2O_3具有良好的稳定性。催化剂在含5%h_2O气氛中催化效率由80%减少至60%,在去除h_2O后抑制作用消失。反应气中通入143mg·m^(-3)SO_2后催化效率由80%降低至62%,停止通入SO_2后活性不能恢复。同时通入143mg·m^(-3)SO_2和5%h_2O,催化效率下降并维持在53%左右,停止通入后活性恢复至67%。通过对SO_2中毒前后的催化剂表征分析可得,SO_2存在条件下生成的硫酸铵盐堵塞了20nm孔径以下的部分孔道,覆盖了催化剂表面活性位点,是引起效率下降的主要原因。

关键词：选择性催化还原蜂窝体mn-Ce/Al2O3 中试催化低温脱硝

Structural characterization of Nd-doped in silica host matrix prepared by wet chemical process

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Journal of Rare Earths 2009年第1期27卷 83-86页

作者： Surender Duhan Sunita Devi m.Singh materials Science Lab Department of Applied Physics Guru Jambheshwar University of Science & Technology materials Science Lab Department of Physics Department of Chemistry Lajpat Rai College Department of Physics Amity School of Engineering and TechnologyAmity University Sec-125

Silica host matrix containing neodymium which is potentially important for the formation of nanocrystalline metal oxides was prepared by solgel method, using tetra-ethoxysilane and Nd（NO3）3 as precursor *** prepared samples were changed from amorphous to nanocrystallites phase at sintered temperature 550 °C（4 h）, 750 °C（8 h） and 950 °C（12 h）.The thermally treated sample microstructures were investigated using X-ray diffraction（XRD）, Fourier transformation infrared spectroscopy（FTIR）, and scanning electron mi-croscopy（SEm）.While a further increase of the temperature at 750 °C and annealing time（8 h） resulted in the formation of cubic and hexagonal Nd2O3 *** constant sintering temperature 950 °C for 12 h, the samples showed sharper and intense *** sizes of Nd2O3 nanocrystallites were characterized by XRD with average size ～46 nm.

关键词： rare earth oxide silica annealing/calcination nanocrystallites

热处理对Ti-mo-V-Nb-Al合金微观结构的影响

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电子显微学报 2006年第B8期25卷 128-129页

作者：成岩韩晓东张泽 WU m h 北京工业大学固体微结构与性能研究所北京100022 memry

热处理对Ti-mo-V-Nb-Al合金微观结构的影响

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电子显微学报 2006年第S1期 142-143页

作者：成岩韩晓东张泽 WU m h 北京工业大学固体微结构与性能研究所 memry Corporation BethelCT06801USA

β-delayed multi-particle Emission From 31^Ar

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原子核物理评论 2016年第2期33卷 221-224页

作者： A. A. Ciemny C. mazzocchi W. Dominik Z. Janas m. Pfutzner m. Pomorski L. Acosta S. Baraeva E. Casarejos J. Duenas-Daz V. Dunin J. m. Espino A. Estrade F. Farinon A. Fomichev h. Geissel A. Gorshkov G. Kaminski O. Kiselev R. Knobel S. Krupko m. Kuich Yu. A. Litvinov G. marquinez-Duran I. martel I. mukha C. Nociforo A. K. Orduz S. Pietri A. Prochazka A. m. Sanchez-Benitez h. Simon B. Sitar R. Slepnev m. Stanoiu P. Strmen I. Szarka m. Takechi Y. Tanaka h. Weick J. S. Winfield Faculty of Physics University of Warsaw 02-093 Warszawa Poland GSI helmholtzzentrum für Schwerionenforschung 64291 Darmstadt Germany INFN Laboratori Nazionali del Sud Via S. Sofia Catania Italy Instituto de Fisica Universidad Nacional Autonoma de Mexico Mexico D. F. 01000 Mexico Joint Institute for Nuclear Research 141980 Dubna Russia University of Vigo 36310 Vigo Spain Department of Applied Physics University of Huelva 21071 Huelva Spain University of Seville 41012 Seville Spain University of Edinburgh EH1 1HT Edinburgh United Kingdom Institute of Nuclear Physics PAN 31-342 Krakow Poland Joint Institute for Nuclear Research 141980 Dubna Moscow Region Russia Faculty of Physics Warsaw University of Technology 00-662 Warszawa Poland Centro de Fisica Nuclear da Universidade de Lisboa 1649-003 Lisboa Portugal Faculty of mathematics and Physics Comenius University 84248 Bratislava Slovakia IFIN-hh Post Office Box MG-6 Bucharest Romania University of Tokyo Japan

The β^+ decay of ^(31)Ar was investigated in an experiment at the GSI-FRS *** ions of interest have been produced in the fragmentation of a ^(36)Ar beam at 880 me V/nucleon and implanted in a time projection chamber with optical readout. In addition to β-delayed one and two proton emission, for the first time the emission of β-delayed 3 protons has been observed. The branching ratio for this decay mode is found to be(0.07 ± 0.02)%.

关键词： 31Ar beta-delayed protons OTPC

载体物化性质对锰铈催化剂Nh_3-SCR脱硝性能的影响

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燃料化学学报 2018年第6期46卷 733-742页

作者：乔南利杨忆新刘清龙宋焕巧禹耕之罗明生北京石油化工学院化学工程学院北京102617 北京航空航天大学材料科学与工程学院北京100191

选取TiO_2、SAPO-34、Al_2O_3三种常用载体,通过浸渍法以mn-Ce-O为活性组分制备了负载型mnCeO_x脱硝催化剂。采用XRD、BET、h_2-TPR、XPS、Py-FTIR等手段对催化剂的固相结构、比表面积、还原性能、表面元素及酸量进行表征分析。结果表明... 详细信息

选取TiO_2、SAPO-34、Al_2O_3三种常用载体,通过浸渍法以mn-Ce-O为活性组分制备了负载型mnCeO_x脱硝催化剂。采用XRD、BET、h_2-TPR、XPS、Py-FTIR等手段对催化剂的固相结构、比表面积、还原性能、表面元素及酸量进行表征分析。结果表明,mnCeO_x/SAPO-34催化剂具有最大的比表面积(439.87 m^2/g),酸量适中,还原性能最差;mnCeO_x/Al_2O_3催化剂中mn^(4+)、Ce^(3+)所占比例较高,但酸性最弱;mnCeO_x/TiO_2催化剂还原性能最优,表面mn、Ce元素浓度最高,并具有大量Lewis酸性位。通过气固相催化反应装置对催化剂性能进行了Nh_3-SCR脱硝评价,结果表明,mnCeO_x/TiO_2催化剂具有较好的脱硝性能,反应温度为280℃时,NO转化率达100%(空速为42000 h^(-1));与催化剂物化性质对比分析,催化剂的氧化还原能力和Lewis酸性位对其脱硝性能至关重要。

关键词：载体锰铈复合氧化物还原性表面酸性低温Nh3-SCR

Simultaneous photoinduced generation of Fe^(2+) and h_2O_2 in rivers:An indicator for photo-Fenton reaction

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Journal of Environmental Sciences 2016年第9期28卷 34-38页

作者： Khan m.G.mostofa hiroshi Sakugawa Institute of Surface-Earth System Science Tianjin University Graduate School of Biosphere Science Department of Environmental Dynamics and ManagementHiroshima University

The photo-Fenton reaction is a key source of the highly reactive hydroxyl radical（hOU） that is produced by the reaction of simultaneous photo-induced generation of Fe^（2＋）-dissolved organic matter（DOm） with h_2O_2 in sunlit surface waters as well as in the treatment of organic pollutants in the advanced oxidation processes（AOPs）.Concentrations of both h_2O_2 and Fe^（2＋）-DOm were dependent on time and total solar intensity flux,and their levels were highest in the diurnal samples collected at noon compared with the samples collected during the period before sunrise and after sunset.h_2O_2 and Fe^（2＋）-DOm concentrations during monthly readings were also found higher in comparison with the diurnal samples,shortly before sunrise or after sunset.A π-electron bonding system is formed between Fe and the functional groups in DOm（Fe-DOm）,through electron donation from the functional groups of DOm to an empty d-orbital of *** π-electron is loosely bound and is highly susceptible to a rapid excitation upon light exposure that will provide better understanding of the formation of aqueous electrons,superoxide radical anions,h_2O_2 and finally,photo-Fenton reactions,*** results imply that simultaneous generation of h_2O_2 and Fe^（2＋）-DOm upon sunlight exposure during the daytime is most likely to be the key photo-Fenton reaction pathway,taking place in surface waters.

关键词： Photo-Fenton reaction Fe^(3+) Fe^(2+) Dissolved organic matter h_2O_2 Light

经静脉肺化学栓塞术用于肺转移瘤的姑息或新辅助疗法

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国际医学放射学杂志 2019年第3期 377-378页

作者：王志炜 J.Vogl A.I.A.mekkawy D.B.Thabet m.El-Sharkaway h.m.Kamel m.h.Albrecht Institute of Diagnostic and Interventional Radiology University Hospital FrankfurtJohann Wolfgang Goethe University Frankfurt

摘要目的回顾性评估采用经静脉肺化学栓塞术(TPCE)的姑息和新辅助疗法治疗肺转移瘤后的肿瘤反应、局部肿瘤控制和病人存活率。材料与方法 2005年6月—

关键词：新辅助疗法肺转移瘤化学栓塞术经静脉