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51.
以两种不同催化体系合成的药用聚异戊二烯橡胶(IR0307和IR80)为研究对象,分别以质量分数为0.9%的氯化钠注射液和纯化水为浸提介质,在两种浸提条件(在高压灭菌器内于121℃下浸提60 min或在密闭容器内于37℃下浸提24 h)下进行浸提处理,然后采用显微镜观察法和四唑盐比色法测定IR0307和IR80的体外细胞毒性,分析不同浸提条件下IR0307和IR80的细胞毒性反应等级。在药用聚异戊二烯橡胶生产中,建议控制催化剂的残留量以及对杂质和金属离子的含量和种类,使用洁净的非污染型防老剂和稳定剂。 相似文献
52.
Effect of growth-interrupted method on quality of AlGaAs/GaAs multiple quantum wells prepared by MBE
AlGaAs/GaAs multi-quantum well (MQW) was prepared by molecular beam epitaxy(MBE) with growth-interrupted heterointerface (GIH) method and continuous growth (CG) method, respectively. The microstructures Of the MQWs were characterized by double-crystal X-ray rocking curve (DCRC) and atomic force microscopy (AFM), and the photoluminescence (PL) properties of the MQWs were also studied. The MQWs grown with GIH method show that higher order satellite peaks of Pendelloesung fiinges are observed in DCRC, the roughness of surface is much reduced in AFM, and the full width at half maximum (FWHM) of exciton line is much narrower in PL. The results indicate that the GIH method reduces the monolayer growth step density at the heterointerface due to the migration of surface atomsfor a few minutes grower interruption, and substantially improves the quality of AlGaAs/GaAs MQWs. 相似文献
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55.
A. Kobayashi 《Journal of Thermal Spray Technology》1996,5(3):298-302
High hardness alumina coatings were formed at atmospheric pressure by gas tunnel plasma spraying, and the characteristics
of these coatings were investigated. The hardness on the cross section of the alumina coating at a short spraying distance
was more than 1300 HV, and the thickness of the hard layer increased with an increase of power input. The microstructure of
the alumina coating was investigated by microscopy and x-ray diffraction (XRD) methods. It was ascertained that the cell size
was small (∼10 μn), and α-alumina was dominant in the high hardness layer of the coating. Finally, the effect of plasma energy
was estimated from these results. 相似文献
56.
多晶体钛拉伸变形表面褶皱的形成及晶粒变形 总被引:2,自引:0,他引:2
李炎 《中国有色金属学报》2004,14(7):1078-1083
用原子力显微镜对多晶体钛拉伸塑性变形中表面褶皱的形成及单个晶粒的变形进行了连续观察和测量.结果表明,表面褶皱随着应变量的增加而增大,而凹凸的相对位置关系不随变形的进行而变化.从单个晶粒来看应变量在0.1附近时由于孪晶的形成产生了新的凹凸,但对整体的表面褶皱凹凸位置关系没有大的影响.表面平均粗糙度和表面最大高低差随应变量的增加近似呈直线性增大,应变量在0.1左右时由于孪晶的形成,使粗糙度有较明显的增大. 相似文献
57.
X.P. Lin Y. Dong X.M. Cao Y. Zhang N.J. Gu X.L. MaDepartment of Materials Science Technology Hebei University of Technology Tianjin China 《金属学报(英文版)》2004,17(6):862-869
1.IntroductionBased on the concept of an invariant plane strain (IPS), phenomenological theory of martensite transformation (PTMT) is established[1-3]. In this case, an invariant plane is obtained by self-accommoda-tion effect between different martensitic variants, and the formula which reveals this self-accommoda-tion effect can be written as … 相似文献
58.
Leukonychia is a medical term for white discoloration appearing on nails. The pathophysiologic mechanisms that cause white discoloration are not entirely clear. We processed a case of leukonychia with scanning electron microscope observation and found many crispy, obviously dissociated "layers" in the lower part of the white nail plate. The dissociated "layers" were composed of thick, loose, coarse keratin bundles intertwined with each other. We believe the dissociated "layers" are related to the clinically noted white discoloration appearing on the nails. 相似文献
59.
Lung-Ming Fu Jing-Hui Wang Wen-Bo Luo Che-Hsin Lin 《Microfluidics and nanofluidics》2009,6(4):499-507
This paper presents a detection scheme for analyzing the temperature distribution nearby the channel wall in a microfluidic
chip utilizing a temperature-dependent fluorescence dye. An advanced optical microscope system—total internal reflection fluorescence
microscope (TIRFM) is used for measuring the temperature distribution on the channel wall at the point of electroosmotic flow
in an electrokinetically driven microfluidic chip. In order to meet the short working distance of the objective type TIRFM
scheme, microscope cover glass slits are used to fabricate the microfluidic chips. The short fluorescence excitation depth
from a TIRFM system makes the intensity information obtained using TIRFM is not sensitive to the channel depth variation which
ususally biases the measured results while using a conventional Epi-fluorescence microscope (EPI-FM). Therefore, a TIRFM can
precisely describe the temperature profile of the distance within 100 nm of the channel wall where consists of the Stern layer
and the diffusion layer for an electrokinetic microfluidic system. Results indicate the proposed TIRFM provides higher measurement
sensitivity over the EPI-FM. Significant temperature gradient along the channel depth is experimentally observed. In addition,
the measured wall temperature distributions can be the boundary conditions for numerical investigation into the joule heating
effect. The proposed method gives a precise temperature profile of microfluidic channels and shows the substantial impact
on developing a numerical simulation model for precisely predicting the joule heating effect in microfluidic chips. 相似文献
60.
超声波扫描显微镜是一种利用超声波为传播媒介的无损检测成像设备,相对于传统的破坏性检测,超声显微镜不会对样品造成损伤,更不会影响样品的性能。本文主要介绍了超声波显微镜的发展现状、应用领域和发展等内容。应用领域主要从材料科学检测行业、半导体测试行业、金刚石检测行业、低压电器检测行业和水冷板检测行业。最后,对超声波扫描显微镜的发展进行了展望。随着超声波技术的发展,声频会越来越高,超声显微镜的本领将越来越大。可以预料,它与其他尖端技术结合,将会发挥出更大更独特的作用。 相似文献