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71.
Michael G. Kane Lawrence Goodman Arthur H. Firester Paul C. van der Wilt Alexander B. Limanov James S. Im 《Journal of the Society for Information Display》2007,15(7):471-478
Abstract— CMOS TFT circuits were fabricated on plastic using sequential laterally solidified silicon combined with a low‐temperature CMOS process. The unity‐gain frequencies of the best of NMOS TFTs are greater than 250 MHz, and the CMOS ring oscillators operate at 100 MHz. To the best of the authors' knowledge, these are the highest‐frequency circuits ever fabricated directly on plastic. This high‐performance CMOS‐on‐plastic process can be applied to the fabrication of AMLCD integrated drivers and AMOLED pixels on plastic substrates. 相似文献
72.
Simple versatile processes combining plasma treatments, micro-contact printing (µCP) or ink-jet printing (IJP), and electroless deposition (ELD) have been developed to produce micrometer and sub-micrometer scale metal (Ni, Ag) patterns at the surface of polymer substrates. Plasma treatments were mainly used to graft the substrate surfaces with either nitrogen-containing functionalities on which a palladium-based catalyst can be subsequently chemisorbed (case of Ni deposition through a tin-free process in solution) or oxygen-containing functionalities on which a tin-based sensitization agent can be subsequently chemisorbed (case of Ag deposition through a redox reaction). µCP of the catalyst or of self-assembled monolayers (SAMs) as well as ink printing were used to obtain locally active or non-active areas at the polymer surfaces. The metal micro-patterns were characterized using optical microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). Surface chemical characterization was carried out by X-ray photoelectron spectroscopy (XPS). 相似文献
73.
Anne Makena Dr. Sander S. van Berkel Dr. Clarisse Lejeune Dr. Raymond J. Owens Dr. Anil Verma Ramya Salimraj Dr. James Spencer Dr. Jürgen Brem Prof. Dr. Christopher J. Schofield 《ChemMedChem》2013,8(12):1923-1929
Serine‐ and metallo‐β‐lactamases present a threat to the clinical use of nearly all β‐lactam antibiotics, including penicillins, cephalosporins, and carbapenems. Efforts to develop metallo‐β‐lactamase (MBL) inhibitors require suitable screening platforms to allow the rapid determination of β‐lactamase activity and efficient inhibition. Unfortunately, the platforms currently available are not ideal for this purpose. Further progress in MBL inhibitor identification requires inexpensive and widely applicable assays. Herein the identification of an inexpensive and stable chromogenic substrate suitable for use in assays of clinically relevant MBLs is described. (6R,7R)‐3‐((4‐Nitrophenoxy)methyl)‐8‐oxo‐7‐(2‐phenylacetamido)‐5‐thia‐1‐azabicyclo[4.2.0]oct‐2‐ene‐2‐carboxylic acid 5,5‐dioxide (CLS405) was synthesised in a three‐step protocol. CLS405 was then characterised spectroscopically, and its stability and kinetic properties evaluated. With a Δλmax value of 100 nm between the parent and hydrolysis product, a higher analytical accuracy is possible with CLS405 than with commonly used chromogenic substrates. The use of CLS405 in assays was validated by MBL activity measurements and inhibitor screening that resulted in the identification of N‐hydroxythiazoles as new inhibitor scaffolds for MBLs. Further evaluation of the identified N‐hydroxythiazoles against a panel of clinically relevant MBLs showed that they possess inhibitory activities in the mid‐ to low‐micromolar range. The findings of this study provide both a useful tool compound for further inhibitor identification, and novel scaffolds for the design of improved MBL inhibitors with potential as antibiotics against resistant strains of bacteria. 相似文献
74.
The quality of GaAs substrate material for manufacturing ion implanted devices is routinely determined by an ion implantation
test. The test involves measuring an electrical quantity, such as sheet resistance, after implanting Si into the substrate.
This work employs GaAs TCAD simulation to address the range of validity of the implantation test and the pitfalls associated
with it. The results show that the electrical measurements are capable of discerning typical variation in the carbon concentration
in the substrate. But, the surface or interface charge on GaAs, which may result from processing involved in wafer preparation,
is also important. Therefore, while the implantation test in most cases is adequate to control the quality of the substrate,
the test is susceptible to misinterpretation owing to the variations arising from the process involved in wafer preparation
for the test. 相似文献
75.
选择具有较低最低不结冰温度(possible lowest unfrozen temperature,θPLU)的结冰基体对于提高过冷水动态制冰系统的制冰率和能量效率以及防止热泵蒸发器结霜具有重要意义.本文从异质形核理论和估算两相间界面能的Good-Girifalco极性理论出发,研究了具有较低θPLU的结冰基体的性质,提出了选择方法.选择了几种具有较低θPLU的结冰基体,测量了其θPLU值.所选择结冰基体的θPLU值比通常使用的不锈钢表面低3℃以上. 相似文献
76.
根据硬盘基板用材料的要求,制备了MgO-Al2O3-SiO2-TiO2-Y2O3高弹性模量玻璃(120GPa),玻璃的弹性模量随组成的变化服从Makishima-Mackenzie理论,MgO,Al2O3,TiO2,Y2O3等具有较高单位体积离解能的氧化物有利于提高玻璃的弹性模量,但玻璃弹性模量的理论计算值低于测试值,这是因为Makishima-Mackenzie理论没有考虑玻璃内阳离子的具体配位,对MgO,Y2O3堆积密度因子的堆导存在误差,因此利用Makishima-Mackenzie理论发展高弹性模量玻璃时应对MgO,Y2O3等氧化物的计算进行修正。 相似文献
77.
We have developed a technique for preparation of cross-sectional transmission electron microscopy samples of reacted and unreacted Nb/al multilayer thin films on sapphire substrates. The choice of substrate was found to be extremely important. Sapphire sputters more slowly than Nb and Nb-compounds and therefore makes it possible to obtain the electron transparent regions in the thin films rather than in the substrate. However, the brittle nature of the sapphire restricts the types of thinning techniques that can be used, requiring extensive ion thinning as a final stage. 相似文献
78.
M. R. ADAMS R. D. COOKE D. R. TWIDDY† 《International Journal of Food Science & Technology》1987,22(2):105-114
Lactic fermented fish products are common in South East Asia. The composition and quality of the products vary considerably since they are usually produced on a small scale and the fermentation of the fish-salt-carbohydrate mixtures depends on the natural microflora. A minced fish-salt-glucose system was used to evaluate the factors that favour a rapid lactic fermentation. Studies with Lactobacillus plantarum and Pediococcus pentosaceus indicated that fermentation rates increase in the range 0–5% w/w of glucose or sucrose, whereas increasing the salt concentration from 0 to 6% slows the rate of pH decrease. Conditions of 1% salt and 4% glucose were used for subsequent studies. The nature of the gas atmosphere during incubation had little effect on fermentation rate and chemical modification of the initial substrate pH with lactic, acetic or citric acid did not assist the lactic fermentation. Incubation temperatures of 15, 24, 30 and 37°C were evaluated: the lactic acid bacterial count rarely exceeded the total spoiler count by more than ten-fold during the first 2 days (although it subsequently increased). Consequently the objective of reducing the pH to below 4.5 within the first 2 days was difficult to achieve. The use of cooked fish minces gave only slight changes in the fermentation rate. 相似文献
79.
80.
A series of glass cloth‐reinforced thermosetting polyimide composites (EG/HTPI) were prepared from E‐glass cloth (EG) and polyimide matrix resins. The polyimide resins were derived from 1,4‐bis(4‐amino‐2‐ trifluoromethyl‐phenoxy)benzene, p‐phenylenediamine, diethyl ester of 3,3′,4,4′‐benzophenonetetracarboxylic acid, and monoethyl ester of cis‐5‐norbornene‐endo‐2,3‐dicarboxylic acid. Based on the rheological properties of the B‐staged polyimide resins, the optimized molding cycles were designed to fabricate the EG/HTPI laminates and the copper‐clad laminates (Cu/EG/HTPI). Experimental results indicated that the EG/HTPI composites exhibited high thermal stability and outstanding mechanical properties. They had flexural strength of >534 MPa, flexural modulus of >20.0 GPa, and impact toughness of >46.9 kJ/m2. The EG/HTPI composites also showed good electrical and dielectric properties. Moreover, the EG/HTPI laminates exhibited peel strength of ~ 1.2 N/mm and great isothermal stability at 288°C for 60 min, showing good potential for application in high density packaging substrates. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献