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41.
A novel field emission pressure sensor has been achieved utilizing carbon nanotubes (CNTs) as the electron source. The sensor consists of the anode sensing film fabricated by wet etching process and multi-wall carbon nanotubes (MWNTs) cathode in the micro-vacuum chamber. MWNTs on the silicon substrate were grown by thermal CVD. The prototype pressure sensor has a measured sensitivity of about 0.17-0.77 nA/Pa (101-550 KPa). The work shows the potential use of CNTs-based field-emitter in microsensors, such as accelerometers and tactile sensors. 相似文献
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The three dimensional problem of steady fluid deposition on an inclined rotating disk is solved by similarity transform. For a given spraying rate there may be one, two or no steady state solution. The inclination causes a downward draining flow and a lateral flow. Perturbation solutions compare well with exact similarity solutions when the fluid film is thin. 相似文献
45.
Fengfu Fu Liangjun Xu Wei Ye Yiquan Chen Mingyu Jiang Xueqin Xu 《中国颗粒学报》2006,4(6):323-326
Different-sized aerosols were collected by an Andersen air sampler to observe the detailed morphology of the black carbon (BC) aerosols which were separated chemically from the other accompanying aerosols, using a Scanning Electron Microscope equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDX). The results indicate that most BC aerosols are spherical particles of about 50 nm in diameter and with a homogeneous surface. Results also show that these particles aggregate with other aerosols or with themselves to form larger agglomerates in the micrometer range. The shape of these 50-nm BC spherical particles was found to be very similar to that of BC particles released from petroleum-powered vehicular internal combustion engines. These spherical BC particles were shown to be different from the previously reported fullerenes found using Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-MS). 相似文献
46.
R. Eric Berson John S. Young Thomas R. Hanley 《Applied biochemistry and biotechnology》2006,130(1-3):612-620
Following detoxification of the liquid hydrolysate produced in a corn stover pretreatment process, inhibitor levels are seen
to increase with the re-addition of solids for the ensuing hydrolysis and fermentation processes. The solids that were separated
from the slurry before detoxification of the liquor contain approx 60% (w/w) moisture, and contamination occurs owing to the
diffusion of inhibitors from the moisture entrained in the porous structure of the corn stover solids into the bulk fluid.
This evidence suggests the need for additional separation and detoxification steps to purge residual inhibitors entrained
in the moisture in the solids. An overliming process to remove furans from the hydrolysate failed to reduce total organic
acids concentration, so acids were removed by treatment with an activated carbon powder. Smaller carbon doses proved more
efficient in removing organic acids in terms of grams of acid removed per gram of carbon powder. Sugar adsorption by the activated
carbon powder was minimal. 相似文献
47.
T. Mihara K. Miyamoto M. Kida T. Sasaki N. Aoki Y. Ochiai 《Superlattices and Microstructures》2003,34(3-6):383
A multiwall carbon nanotube crossroads has been fabricated by a manipulation technique using a glass microcapillary, and the low temperature transport properties investigated. The two-terminal conductance of an individual tube shows Tomonaga–Luttinger liquid behavior G∝Tα at high temperature and dI/dV ∝V α at low temperature. However, no evidence of such a power-law behavior is obtained in the four-terminal conductance at the junction, where the conductance shows an almost metallic behavior ‘corrected’ by weak localization. Weak localization would essentially appear in electron states at the junctions of MWNTs. 相似文献
48.
为了使光盘获得优良的记录/读出性能并能够长期稳定地使用,必须优化设计相变光盘的多层膜结构。采用自行设计的模拟分析相变光盘读出过程设计软件,从光学角度出发模拟计算了蓝光(405nm)相变光盘的膜层结构,研究了多层膜系的反射率和反射率对比度等光学参量与各层膜厚度和槽深的关系。研究得出的最佳多层膜结构为:下介电层/记录层/上介电层/反射层的厚度对于台记录为100nm/10nm/25nm,/60nm,而对于槽记录则为140nm/15nm/30nm,/60nm,槽深为50nm。模拟计算结果对于将来高密度蓝光相变光盘的制备具有一定的指导意义。 相似文献
49.
本文采用高分辨率格式和多块多网格方法求解雷诺平均Navier-Stokes方程,数值模拟多排叶片内的三维粘性流动;使用数值激盘模拟叶片排的存在,研究叶片排与非轴对称排气部件之间的相互作用以及复杂的内部流动。文中描述了数值方法,给出了NASA透平导叶和单级透平内部流场的数值结果及其与相应实验结果的对比,也给出了多级透平内部流场的数值结果,以及透平与排气部件之间的耦合流场的结果。 相似文献
50.
Qing Shi Dong Yang Yanlei Su Jian Li Zhongyi Jiang Yanjun Jiang Weikang Yuan 《Journal of nanoparticle research》2007,9(6):1205-1210
Lipase from Candida rugosa was covalently anchored onto acid-treated multi-walled carbon nanotubes (MWNTs) through a self-catalytic mechanism. A variety
of characterization techniques including FTIR, Raman spectroscopy, and XPS were employed to demonstrate the formation of the
ester linkage between lipase and MWNTs. The MWNTs-lipase biocomposites showed significantly increased solubility in some common-used
organic solvents, such as THF, DMF and chloroform. This study may offer a novel and facile route for covalent modification
of carbon nanotubes, and expand the potential utilization of both lipases and MWNTs in the fields of biocatalyst and biosensor. 相似文献