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61.
We report on the excellent reliability performance of high-voltage (HV) gate stacks comprised of a thin thermal oxide and a thicker HTO layer. Time-to-breakdown of the developed stacks exceeded corresponding values for thermal HV oxides of the same thickness. Peculiarities of current relaxation in course of electrical stress tests are interpreted by injected charge trapping in HTO and new trap generation. Charge trapping in optimized HTO is low and guarantees reliable device operation.  相似文献   
62.
Ionic Liquids (ILs) have been used for polycondensation processes, especially for polyimide synthesis. The influence of various reaction parameters including IL's cations and anions nature, monomer structure and concentration, reaction temperature, upon polyimide molecular weight (ηinh) was investigated. The possibility of process activation by the application of IL's small additives in one step polyimide synthesis in common organic solvents was demonstrated. The peculiarities of C-H?Br contacts in solid state were carried out using single crystal X-ray diffraction data. Various high molecular weight polyimides including commercial and sulfonated ones have been obtained in quantitative yields with inherent viscosities ranging from 0.10 to 2.17 dl g−1.  相似文献   
63.
Emphasizes the attributional component of interpersonal communication in psychotherapy and human-relations training groups. The respective aims of these 2 types of groups are compared, and the role of productive dialog as a means to achieve these aims is discussed. Empathic and nonempathic forms of communication are defined, and their interaction with a personality property, self-cohesiveness, is presented. Implications for intervention in the 2 types of groups are discussed. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
Effects of incident illumination on phase-contrast images obtained by means of free-space propagation are investigated under the "transport-of-intensity" approximation. Analytical expressions for image intensity distribution are derived in the cases of coherent quasi-plane and quasi-spherical incident waves, as well as for spatially incoherent and quasi-homogeneous sources and some other types of sources. Practical methods for measuring the relevant parameters of the incident radiation are discussed together with formulas allowing one to calculate the effect of these parameters on the image intensity distribution. The results are expected to be useful in quantitative in-line imaging, phase retrieval, and tomography with polychromatic and spatially partially coherent radiation. As an application we present a method for simultaneous "automatic" phase retrieval and spatial deconvolution in in-line imaging of homogeneous objects using extended polychromatic x-ray sources.  相似文献   
65.
Catheter-associated urinary tract infections (CAUTIs) are among the most common bacterial infections associated with medical devices.In the current study,the synthesis,coating,antibiofilm properties,and biocompatibility of urinary catheters coated with Zn-doped CuO (Zn0.12Cu0.~O) nanoparticles (NPs) were examined.The doped NPs were synthesized and subsequently deposited on the catheter by the sonochemical method.The coated catheters displayed high antibiofilm activity and promising biocompatibility,as indicated by low in vitro cytotoxicity,negligible associated cytokine secretion,and absence of detectable irritation.The biocompatibility and ability of the Zn-doped CuO coating to inhibit biofilm formation were also evaluated in vivo using a rabbit model.Rabbits catheterized with uncoated catheters scored positive for CAUTI by day 4 of the experiment.In contrast,rabbits catheterized with Zn-doped CuO-coated catheters did not exhibit CAUTI until day 7 or remained completely uninfected for the whole duration of the 7-day experiment.Furthermore,.the in vivo biocompatibility assays and examinations supported the biosafety of Zn-doped CuO-coated catheters.Taken together,these data highlight the potential of Zn-doped CuO nanocomposite as effective antibiofilm compound.  相似文献   
66.
Using polymeric ionic liquids, namely poly[1-(2-(2-(2-(methacryloyloxy)ethoxy)ethoxy)ethyl)-3-methylimidazolium]bis(trifluoromethylsulfonyl)imide or tetracyanoborate, and poly(3,4-ethylenedioxythiophene) (PEDOT) as an ion conductor and electrodes, respectively, the all-polymer-based thin-film symmetrical electrochromic devices (ECDs) have been constructed and tested. The proposed architecture serves as a prove of concept that polymeric ionic liquids (PILs) can be themselves used as solid electrolytes thus avoiding any electrolyte leakage since the ionic liquid species are grafted on the polymer backbone. Three different methods for the synthesis of PEDOT electrode films, including two new approaches consisted in vapor phase polymerization of 3,4-ethylenedioxythiophene (EDOT) in the presence of ionic monomer and poly(ethylene glycol)(di)methacrylates, have been investigated. Two oxidants, Fe[(CF3SO2)2N]3 and Fe[(CN)4B]3, bearing the same anions as PILs were prepared for the first time and utilized in the vapor phase polymerization of EDOT. It was found that the more compact structure and the highest conductivity are achieved for PEDOT electrodes prepared by vapor phase polymerization of EDOT in the presence of ionic monomer and poly(ethylene glycol)(di)methacrylates, followed by radical polymerization of the latters. The simplicity of ECDs assembly, their fast switching times (3–5 s), high coloration efficiency (up to 430 cm2/C), satisfactory optical contrast (up to 28.5%), absence of any liquids and good performance in air and in vacuum were found among the advantages of the proposed technology.  相似文献   
67.
A vision based approach for calculating accurate 3D models of the objects is presented. Generally industrial visual inspection systems capable of accurate 3D depth estimation rely on extra hardware tools like laser scanners or light pattern projectors. These tools improve the accuracy of depth estimation but also make the vision system costly and cumbersome. In the proposed algorithm, depth and dimensional accuracy of the produced 3D depth model depends on the existing reference model instead of the information from extra hardware tools. The proposed algorithm is a simple and cost effective software based approach to achieve accurate 3D depth estimation with minimal hardware involvement. The matching process uses the well-known coarse to fine strategy, involving the calculation of matching points at the coarsest level with consequent refinement up to the finest level. Vector coefficients of the wavelet transform-modulus are used as matching features, where wavelet transform-modulus maxima defines the shift invariant high-level features with phase pointing to the normal of the feature surface. The technique addresses the estimation of optimal corresponding points and the corresponding 2D disparity maps leading to the creation of accurate depth perception model.  相似文献   
68.
增加IC运放的输出电压通常要增加大电压外接晶体管.然后形成的电路需要经过校正才能保持它的工作特性.这种校正是很困难的,尤其是对精密放大器而言.  相似文献   
69.
Recent attempts to achieve 400 GHz or higher fT and f MAX with InP heterojunction bipolar transistors (HBTs) have resulted in aggressive scaling into the deep submicrometer regime. In order to alleviate some of the traditional mesa scaling rules, several groups have explored selectively implanted buried subcollectors (SIBS) as a means to decouple the intrinsic and extrinsic collector design. This allows tauC to be minimized without incurring a large total CBC increase, and hence, a net improvement in fT and fMAX is achieved. This paper represents the first investigation into the series resistance and capacitance characteristics of submicrometer-width SIBS regions (as narrow as 350 nm) for InP double HBTs. Although the SIBS resistance is higher than that of epitaxially grown layers, the SIBS concept is able to provide good dopant activation and a significant decrease in CBC. S-parameter measurements are presented to clarify the impact of SIBS geometry variations, caused by both intentional device design and process variations, on fT and fMAX. Parasitic resistances and high background doping limit the fT improvement, but the CBC reduction is sufficient to demonstrate a 30% increase in fMAX. Results indicate that further improvements in fT and fMAX using the SIBS concept will be possible  相似文献   
70.
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