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1.
Flotation is a water treatment alternative to sedimentation, and uses small bubbles to remove low-density particles from potable water and wastewater. The effect of zeta potential, bubble size and particle size on removal efficiency of the electro-flotation process was investigated because previous model-simulations indicated that these attributes are critical for high collision efficiency between micro-bubbles and particles. Solutions containing Al3+ as the metal ion were subjected to various conditions. The zeta potentials of bubbles and particles were similar under identical conditions, and their charges were influenced by metal ion concentration and pH. Maximum removal efficiency was 98 and 12% in the presence and absence of flocculation, respectively. Removal efficiency was higher when particle size was similar to bubble size. These results agree with modelling simulations and indicate that collision efficiency is greater when the zeta potential of one is negative and that of the other is positive and when their sizes are similar. 相似文献
2.
A new excimer laser annealing (ELA) process that uses a floating amorphous-Silicon (a-Si) thin film with a multichannel structure is proposed for high-performance poly-Si thin-film transistors (TFTs). The proposed ELA method produces two-dimensional (2-D) grain growth, which can result in a high-quality grain structure. The dual-gate structure was employed to eliminate the grain boundaries perpendicular to the current flow in the channel. A multichannel structure was adapted in order to arrange the grain boundary to be parallel to the current flow. The proposed poly-Si TFT exhibits high-performance electrical characteristics, which are a high mobility of 504 cm/sup 2//Vsec and a low subthreshold slope of 0.337 V/dec. 相似文献
3.
本文首先给出了一种新的2.5D 实体表示法,然后在此基础上提出了“原型”的概念。原型法的思想运用在结构库的管理中主要体现在它将模具结构与构成这种结构的零件之间的强联系变成弱联系,结构库面向的对象是一个具有整体性和可运算性的结构原型。这样的原型结构库基本上达到了通用性与开放性的要求。 相似文献
4.
Xiang‐Dan Li Zhen‐Xin Zhong Sang‐Hoon Han Seung Hee Lee Myong‐Hoon Lee 《Polymer International》2005,54(2):406-411
From chloromethylated polyimide, a useful starting material for modification of aromatic polyimides, a thermocurable transparent polyimide having acrylate side groups was prepared. In the presence of 1,8‐diazabicyclo[5,4,0]undec‐7‐ene, chloromethylated polyimide was esterified with acrylic acid to synthesize poly(imide methylene acrylate). The polymer was soluble in organic solvent, which makes it possible to prepare a planar film by spin coating. The polymer film became insoluble after thermal treatment at 230 °C for 30 min. Optical transparency of the film at 400 nm (for 1 µm thickness) was higher than 98 % and not affected by further heating at 230 °C for 250 min. Adhesion properties measured by the ASTM D3359‐B method ranged from 4B to 5B. Preliminary results of planarization testing showed a high degree of planarization (DOP) value (>0.53). These properties demonstrate that poly(imide methylene acrylate) could be utilized as a thermocurable transparent material in fabricating display devices such as TFT‐LCD. Copyright © 2004 Society of Chemical Industry 相似文献
5.
在第一部分综合讨论的基础上对甘三酯立体专一分析方法作了初步探讨。以液体油(菜油)及固体脂(猪脂)为基质,系统地研究了这一分析方法,取得了经验并补充了一些具体验证方法。分析液体油的结果与文献数据相一致,分析猪脂的结果欠佳,还存在一些问题需待进一步研究。 相似文献
6.
Youngmo Han 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2007,37(6):854-863
This paper is about gaze control in active vision. The problem to tackle is, given a camera imaging a particular 3-D point, to place the 3-D point at the center of the image by rotating the camera about its own optical center. For separating this procedure from structure estimation, we use a normalized camera coordinate system, which leads to formulation defined on the unit sphere. In designing the algorithm, we try to avoid the disadvantages of local coordinates or approximation. For this purpose, we design the algorithm by considering the intrinsic geometric properties of the underlying space, not using any kinds of parameterization or approximation. The proposed algorithm is simple and of a closed form, and that makes it suitable for real-time application. 相似文献
7.
Cheol-Min Park Byung-Hyuk Min Jae-Hong Jun Juhn-Suk Yoo Min-Koo Han 《Electron Device Letters, IEEE》1997,18(1):16-18
We have fabricated a self-aligned offset-gated poly-Si thin film transistor (TFT) by employing a novel photoresist reflow process. The gate structure of the new device is consisted of two unique patterns: A main-gate and a sub-gate. The new fabrication method extends the gate-oxide over the offset region. With the assistance of the sub-gate and reflowed photoresist a self-aligned offset region is successfully obtained due to the offset oxide acting as an implantation mask. The poly-Si TFT with symmetrical offsets is easily fabricated and the new method does not require any additional offset mask step. Compared with the misaligned offset gated poly-Si TFTs, excellent symmetric electrical characteristics are obtained 相似文献
8.
Motoharu Fujigaki In Hong Yang Yoshiharu Morimoto Eung Kyo Han 《NDT & E International》1996,29(4):197-203
There is no good method to measure the shape and the strain distributions of a structure changing with time. We have previously proposed the Fourier transform grid method (FTGM) to measure the three-dimensional shape and surface strain distributions of stationary objects by analysing the two-dimensional grating images recorded with two cameras. In the stereoscopic method, it is very important to determine the accurate geometric parameters of the camera system. In this paper, the positions and the directions of cameras are accurately determined using the FTGM applied to images of a reference object on which a two-dimensional grating is drawn. Applications for analysing shape and strain distributions of vibrating rubber plates and a moving human skin are shown. 相似文献
9.
10.
部分种子成分的特征X射线在等效生物材料中衰减的测定 总被引:6,自引:5,他引:1
用Si(Li)探测器实现了Na、Mg、S、Cl的特征X射线在有机膜中的相对衰减以及与O、K元素的特征X射线能量相当的X射线或轫致辐射在有机膜中的相对衰减,分别得出了它们减的数学描述,并把实验得到不同能量的X射线在有机膜中的质量吸收系数与Berkeley的OCG软件计算出的结果相比,相关都小于30%。 相似文献