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81.
粒子高速冲击其他材料并进入其中叫作离子注入。在半导体工业中,这个过程用来向纯净衬底上掺杂杂质而形成半导体。半导体工艺中这个特别的步骤是由一种特殊的粒子加速装置完成,这就是离子注入机。 相似文献
82.
Brice T. Hughes Jordan M. Berg Darryl L. James Akif Ibraguimov Shaorong Liu Henryk Temkin 《Microfluidics and nanofluidics》2008,5(6):761-774
This paper presents a numerical steady-state model of ion transport in micro- and nanofluidic devices with widely varying
geometric scale, such as transitions between micro- and nanochannels. Finite element or finite volume simulation of such problems
is challenging, due to the number of elements needed to produce a satisfactory mesh. Here, only the lengthwise channel dimension
is meshed; standard analytical approximations are used to incorporate cross-channel properties. Singularly perturbed cases
are built up by continuation. The method is shown to reproduce our previously reported measurements of electric double-layer
effects on conductivity, ion concentration, and ion enhancement and depletion. Comparison with 2-D simulations reported in
the literature shows that effects on accuracy due to the 1-D approximation are small. The model incorporates analytical models
of surface charge density taken from the literature. This enables predictive simulation with reasonable accuracy using published
parameter values, or these values may be tuned based on experiment to give improved results. Use of the model for iterative
design and parameter estimation is demonstrated. 相似文献
83.
应用硫酸铵分段沉淀和 Ultrogei AcA_(34)凝胶过滤对破伤风毒进行了提纯,并对形成的离子通道在中毒作用中的功能进行了讨论。提纯的毒素与抗粗制毒素血清形成一条沉淀线,于聚丙烯酰胺凝胶电泳中形成单一的蛋白带,分子量为15万,等电点为5.95,毒力为1~3×10~4MLD/μg 蛋白。给小鼠注射低剂量毒素引起迟发性强直性痉挛;注射高剂量毒素引起快速的类肉毒毒素的松弛性麻痹,直至死亡。应用 Patch clamp 技术,破伤风毒素于人工磷脂膜上形成离子通道。只有当膜两侧存有 pH 梯度时毒素才形成离子通道,因此是 pH 依赖的。通道的电导系数为9 PS。 相似文献
84.
本文概述了聚合物膜离子选择电极的发展,制备、应用等方面的研究情况;将聚合物膜离子选择电极分为固态膜类和液态膜类,分别对其优缺点和发展前景加以分析;并讨论了聚合物在敏感膜中的作用,以及聚合物结构对敏感膜性能的可能影响。 相似文献
85.
采用离子束溅射方法在Si衬底上制备Si/Ge多层膜,通过改变生长温度、溅射速率等因素得到一系列Si/Ge多层膜样品;通过X射线衍射、Raman散射等表征方法研究薄膜结构与生长条件的关系。在小束流(10mA)、室温条件下制备出界面清晰、周期完整的Si/Ge多层膜。 相似文献
86.
CrAlN is a good candidate as an alternative to conventional CrN coatings especially for high temperature oxidation-resistance applications. Different CrAlN coatings were deposited on hardened steel substrates by cathodic arc evaporation (CAE) from chromium-aluminum targets in a reactive nitrogen atmosphere at negative substrate bias between − 50 and − 400 V. The negative substrate bias has important effects on the deposition growth rate and crystalline structure. All our coatings presented hardness higher than conventional CrN coatings. The friction coefficient against alumina and tungsten carbide balls was around 0.6. The sliding wear coefficient of the CrAlN coatings was very low while an important wear was observed in the balls before a measurable wear were produced in the coatings. This effect was more pronounced as the negative substrate bias was increased. 相似文献
87.
Ichiro Takano Yoshiharu Arai Michiko Sasaki Yoshio Sawada Kaori Yamada Takayoshi Yagasaki Yuji Kimura 《Vacuum》2006,80(7):788-792
Biodegradable plastics can be used as conventional plastics, while on disposal they decompose to water and carbon dioxide by microorganisms existing in natural environment. Products using biodegradable plastics have recently been developed in many companies pursuing ecology. In this study, surface modification of biodegradable plastics was carried out by inert ion beams for improvement of photo deterioration under an ultraviolet ray. The hardness of biodegradable plastics tended generally to decrease with irradiation of an ultraviolet ray. In this method, the hardness of ion-bombarded biodegradable plastics was kept at an initial value under an ultraviolet ray, because the modified layer by ion bombardment intercepted an ultraviolet ray. The hardness of He+ ion-bombarded biodegradable plastics showed larger value than that of Ar+ ion bombardment. He+ ion bombardment at ion energy of 10 keV produced the suitable property with both of high transmittance of a visible ray and high interception of an ultraviolet ray in a surface layer of biodegradable plastics. 相似文献
88.
A review of the latest research and the new experimental data obtained by the authors on changes in the isotope composition in the near-surface layers of solids in ion scattering processes, ion sputtering, the secondary ion emission, ion implantation, electrolytic saturation by hydrogen isotopes, thermo-diffusion from external source, and chemical solution action is presented. In all these processes appreciable changes in natural isotopic composition of the near-surface layers have been registered. These changes take place among the secondary emitted and reflected particles also. Investigations of these effects have been made by the methods of secondary ion mass spectrometry (SIMS) and secondary ion energy-mass spectrometry (SIEMS). The many-isotopic samples of molybdenum, nickel implanted in copper, various titanium modifications, thin film titanium-aluminum systems and some others have been used. The general regularities in the changes in the isotope composition by different processes are found. Possible mechanisms of these processes are discussed. 相似文献
89.
Undoped (IO) and Sn-doped In2O3 (ITO) films have been deposited on glass and polymer substrates by an advanced ion beam technologies including ion-assisted deposition (IAD), hybrid ion beam, ion beam sputter deposition (IBSD), and ion-assisted reaction (IAR). Physical and chemical properties of the oxide films and adhesion between films and substrates were improved significantly by these technologies. By using the IAD method, non-stoichiometry and microstructure of the films were controlled by changing assisted oxygen ion energy and arrival ratio of assisted oxygen ion to evaporated atoms. Relationships between structural and electrical properties in ITO films on glass substrates were intensively investigated by using the IBSD method with changing ion energy, reactive gas environment, and substrate temperature. Smooth-surface ITO films (Rrms ≤ 1 nm and Rp-v ≤ 10 nm) for organic light-emitting diodes were developed with a combination of deposition conditions with controlling microstructure of a seed layer on glass. IAR surface treatment enormously enhanced the adhesion of oxide films to polymer substrate. The different dependence of IO and ITO films' properties on the experimental parameters, such as ion energy and oxygen gas environment, will be intensively discussed. 相似文献
90.