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排序方式: 共有2033条查询结果,搜索用时 15 毫秒
61.
Simoen E. Eneman G. Verheyen P. Loo R. Kristin De Meyer Claeys C. 《Electron Devices, IEEE Transactions on》2006,53(5):1039-1047
The impact of different processing factors on the low-frequency (LF) noise of nMOSFETs fabricated in strained-silicon (SSi) substrates will be described. It is shown that the use of an SSi substrate can yield improved LF noise performance compared with standard Czochralski silicon material. This is demonstrated for both full-wafer and selective epitaxial SSi material. The lower 1/f noise points to an improved gate oxide quality, i.e., with a lower interface and bulk defect density, and is correlated with the low-field mobility or transconductance of the transistors. At the same time, it will be demonstrated that there exist defect-related LF noise mechanisms, which generally give rise to excess generation-recombination (GR) noise. Associated with this GR noise, a degradation of either the OFF-state leakage current or the mobility (transconductance) of the devices is observed. It is clear that noise is a sensitive parameter to local defectiveness and may be a useful tool for both materials' characterization and the analysis of processing-related device degradation mechanisms. 相似文献
62.
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64.
G. Chai R. van Staden S.H. Chowdhury Y.C. Loo 《International Journal of Pavement Engineering》2014,15(1):1-8
This paper discusses the ageing of asphalt binder of long-term pavement performance (LTPP) sites in Southeast Queensland. The effects of pavement age on binder deterioration were examined by performing ‘Shell’ sliding plate micro-viscometer laboratory tests in accordance with Australian and New Zealand Standard AS/NZS 2341.5: 1997. The tests were carried out on bituminous core samples obtained from the LTPP sites to determine the apparent viscosity of the asphalt binder. A binder deterioration model (BDM) was developed by establishing a relationship between the apparent viscosities of the binder with pavement age. The apparent viscosity data generated using the BDM were compared with that computed using the bitumen hardening model developed by Oliver (2003). The two models show a consistent trend in the binder deterioration, and the results were analysed statistically using regression analysis, Root Mean Square Error and t-test methods. The t-test shows that the data generated by the BDM have no significant deviation from the prediction by Oliver's model. 相似文献
65.
Stéphanie van Loo Serguei Stoukatch Michael Kraft Tristan Gilet 《Microfluidics and nanofluidics》2016,20(10):146
In microfluidics, flow focusing is widely used to produce water-in-oil droplets in microchannels at high frequency. We here report an experimental study of droplet formation in a microfluidic cross-junction with a minimum number of geometrical parameters. We mostly focus on the squeezing regime, which is composed of two distinct steps: filling and pinching. The duration of each step (and corresponding volumes of each liquid phase) is analyzed. They vary according to both water and oil flow rates. These variations provide several insights about the fluid flows in both phases. We propose several scaling laws to relate the droplet volume and frequency to the flow rate of both phases. We also discuss the influence of surfactant and channel compliance on droplet formation. 相似文献
66.
Wing-Hin Lee Ching-Yee Loo Kim Linh Van Alexander V. Zavgorodniy Ramin Rohanizadeh 《Journal of the Royal Society Interface》2012,9(70):918-927
Hydroxyapatite (HA) is a material of choice for bone grafts owing to its chemical and structural similarities to the mineral phase of hard tissues. The combination of osteogenic proteins with HA materials that carry and deliver the proteins to the bone-defective areas will accelerate bone regeneration. The study investigated the treatment of HA particles with different amino acids such as serine (Ser), asparagine (Asn), aspartic acid (Asp) and arginine (Arg) to enhance the adsorption ability of HA carrier for delivering therapeutic proteins to the body. The crystallinity of HA reduced when amino acids were added during HA preparation. Depending on the types of amino acid, the specific surface area of the amino acid-functionalized HA particles varied from 105 to 149 m2 g–1. Bovine serum albumin (BSA) and lysozyme were used as model proteins for adsorption study. The protein adsorption onto the surface of amino acid-functionalized HA depended on the polarities of HA particles, whereby, compared with lysozyme, BSA demonstrated higher affinity towards positively charged Arg-HA. Alternatively, the binding affinity of lysozyme onto the negatively charged Asp-HA was higher when compared with BSA. The BSA and lysozyme adsorptions onto the amino acid-functionalized HA fitted better into the Freundlich than Langmuir model. The amino acid-functionalized HA particles that had higher protein adsorption demonstrated a lower protein-release rate. 相似文献
67.
Pei-Lee Teh Pervaiz K. Ahmed Alan H.S. Chan Jasmine M.Y. Loo Soon-Nyean Cheong 《Behaviour & Information Technology》2017,36(1):33-42
Recognising the rise of an aging population and independent living among older adults, many governments and organisations have developed and promoted new technologies in the form of gerontechnologies to support the needs and enhance the well-being of older adults. However, the adoption of products using such technology remains modest among the aging population. This study introduces the notion of power in the form of power posing and examines its impact on new technology adoption, particularly gerontechnology, among older adults. Using an experimental approach on a sample of older adults exposed to an in-house near-field communication-enabled light system, the study finds that high-power poses have a greater and more positive impact on older adults’ perceived ease of use of, perceived usefulness of, and intentions to use gerontechnology than low-power poses. Implications, limitations, and future research directions are discussed. 相似文献
68.
Joseph Berry Tonio Buonassisi David A. Egger Gary Hodes Leeor Kronik Yueh‐Lin Loo Igor Lubomirsky Seth R. Marder Yitzhak Mastai Joel S. Miller David B. Mitzi Yaron Paz Andrew M. Rappe Ilan Riess Boris Rybtchinski Oscar Stafsudd Vladan Stevanovic Michael F. Toney David Zitoun Antoine Kahn David Ginley David Cahen 《Advanced materials (Deerfield Beach, Fla.)》2015,27(35):5102-5112
69.
自 1963 年以来,新加坡开展实施了绿化计划,并经历了从“花园城市”到“花园中的亲生态城市”的演变。为了在新加坡实现生物多样性保护,国家公园局制定了自然保护蓝图,重点介绍该规划实施的关键是利用技术创新。新加坡城市生物多样性指数是一种评价生物多样性成效的自我评估工具,已在全球范围内的多个城市得到应用。 相似文献
70.
Leslie S. Loo 《Polymer》2004,45(17):5933-5939
A method to determine the orientation distribution function of montmorillonite clay in nylon 6 nanocomposite films by a combination of infrared (FTIR) trichroic analysis and transmission electron microscopy (TEM) image analysis is described. The structural absorbance of the nanoclay Si-O vibrations was obtained by the sample tilting method described by Schmidt [Schmidt PG. J Polym Sci: Part A 1963;1:1271-1292]. A nonlinear least squares regression was performed to extract the absorbance of individual peaks. The montmorillonite clay orientation in spun cast nylon 6 films can be described by a Gaussian function having a standard deviation of 15° i.e. 95% of the clay platelets are tilted at an angle of within ±30° of the plane of the film. The transition dipole moment angles of the 1018 and 1046 cm−1 clay vibrations are determined to be 18 and 16° relative to the clay surface, respectively. The orientation of nylon 6 in the nanocomposite was also investigated based on the NH stretching mode. The NH bonds are found to be less preferentially oriented along the plane of the film surface compared to pure nylon 6 film. 相似文献