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51.
52.
Guest editorial wireless ad hoc networks 总被引:1,自引:0,他引:1
53.
S. Tanemura L. Miao Y. Kajino Y. Itano M. Tanemura S. Toh K. Kaneko Y. Mori 《Journal of Materials Science: Materials in Electronics》2007,18(1):43-46
We have succeeded to fabricate the thin films (350 nm in total thickness) consisting of semiconducting Vanadium-oxide (VO0.9+x (0.30≦x < 0.37)) nano-particles with 3.47 nm in averaged diameter by using the combined magnetron sputtering and gas aggregation methods. The optical band gap of the film is evaluated as 3.88 eV under the ad hoc assumption of direct allowed optical transition mode by spectroscopic ellipsometry. This value is expanded by 0.18 eV comparing with the estimated VO bulk value. The widening of band gap might be due to the lattice strain and/or the quantum confinement effect of the composed nano-particles. 相似文献
54.
Trianni A Chizzola G Toh H Quai E Cragnolini E Bernardi G Proclemer A Padovani R 《Radiation protection dosimetry》2005,117(1-3):241-246
With the increase in number and complexity of interventional cardiology (IC) procedures, it is important to monitor skin dose in order to decrease skin injuries. This study investigated radiation doses for patients undergoing IC procedures, compare results with the literature and define a local dose-area product trigger level for operators to identify situations likely to exceed the threshold for transient skin erythema of 2 Gy. Dosimetric data were collected for 77 haemodynamic and 90 electrophysiological procedures. Mean maximum local skin doses (MSDs) were 0.28 Gy for coronary angiography, 1.03 Gy for percutaneous transluminal coronary angioplasty (PTCA), 0.03 Gy for pacemaker insertion, 0.17 Gy for radiofrequency ablation for nodal tachycardia, 0.10 Gy for WPW and 0.22 Gy for atrial flutter. Since MSD values for the other procedures were well below the deterministic effect limit, a trigger level of 140 Gy cm2 was derived for PTCA procedures alone. 相似文献
55.
High‐Temperature Ionic Epitaxy of Halide Perovskite Thin Film and the Hidden Carrier Dynamics
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Yiping Wang Xin Sun Zhizhong Chen Yi‐Yang Sun Shengbai Zhang Toh‐Ming Lu Esther Wertz Jian Shi 《Advanced materials (Deerfield Beach, Fla.)》2017,29(35)
High‐temperature vapor phase epitaxy (VPE) has been proved ubiquitously powerful in enabling high‐performance electro‐optic devices in III–V semiconductor field. A typical example is the successful growth of p‐type GaN by VPE for blue light‐emitting diodes. VPE excels as it controls film defects such as point/interface defects and grain boundary, thanks to its high‐temperature processing condition and controllable deposition rate. For the first time, single‐crystalline high‐temperature VPE halide perovskite thin film has been demonstrated—a unique platform on unveiling previously uncovered carrier dynamics in inorganic halide perovskites. Toward wafer‐scale epitaxial and grain boundary‐free film is grown with alkali halides as substrates. It is shown the metal alkali halides could be used as universal substrates for VPE growth of perovskite due to their similar material chemistry and lattice constant. With VPE, hot photoluminescence and nanosecond photo‐Dember effect are revealed in inorganic halide perovskite. These two phenomena suggest that inorganic halide perovskite could be as compelling as its organic–inorganic counterpart regarding optoelectronic properties and help explain the long carrier lifetime in halide perovskite. The findings suggest a new avenue on developing high‐quality large‐scale single‐crystalline halide perovskite films requiring precise control of defects and morphology. 相似文献
56.
A biometric discretization scheme converts biometric features into a binary string via segmenting every one-dimensional feature space into multiple labelled intervals, assigning each interval-captured feature element with a short binary string and concatenating the binary output of all feature elements into a bit string. This paper proposes a bit allocation algorithm for biometric discretization to allocate bits dynamically to every feature element based on a Binary Reflected Gray code. Unlike existing bit allocation schemes, our scheme bases upon a combination of bit statistics (reliability measure) and signal to noise ratio (discriminability measure) in performing feature selection and bit allocation procedures. Several empirical comparative studies are conducted extensively on two popular face datasets to justify the efficiency and feasibility of our proposed approach. 相似文献
57.
随着存储器需求的增加以及制造技术的进步,嵌入式存储器在SOC系统中的地位越来越重要。与传统的分立存储器件测试相比,嵌入式存储器的测试呈现出新的挑战。本文试图全面叙述嵌入式存储器的各种结构,并介绍各种DFT(可测性设计)测试技术,如SCAN〔扫描〕、MBIST(存储器内建自测试)以及BISR(内建自修复)。 相似文献
58.
Desuo Zhang Guoyang William Toh Hong Lin Yuyue Chen 《Journal of Materials Science》2012,47(15):5721-5728
This research presents a generic strategy to fabricate antibacterial textile through in situ synthesis of silver nanoparticles on the fabric with smart polymeric molecules. Silk fabric and polyamide network polymer (PNP) were chosen for this study. PNP which has numerous amino groups and three-dimensional structure was applied to entrap silver ions into silk fabric. The pretreated silk fabrics were heated by steam method to make silver nanoparticles synthesized in situ on them without any other reductant and linker to provide silk fabric with antibacterial properties. The results indicated that the treated silk fabrics had excellent antibacterial activity and laundering durability. The quantitative bacterial tests showed the bacterial reduction rates of Staphylococcus aureus and Escherichia coli were able to reach above 99 % with not more than 0.05 mmol/L of AgNO3. The whiteness of silk fabric only changed from 90.47 to 86.49. The antibacterial activity of the treated silk fabric was maintained at 98.86 % reduction even after being exposed to 30 consecutive home laundering conditions. In addition, the results of scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy confirmed that silver nanoparticles had generated and dispersed well in Ag0 form on the surface of silk fibers. The understanding acquired from this work will allow one to work with the preparation of other silver nanoparticles functional textiles with excellent antibacterial activities and laundering durability through this facile, eco-friendly in situ synthesis method. 相似文献
59.
Kripesh V. Seung Wook Yoon Aibin Yu Pinjala D. Lau J.H. Khan N. Archit G. Kok Chuan Toh 《Components and Packaging Technologies, IEEE Transactions on》2009,32(3):566-571
This paper presents micro fabrication process and wafer-level integration of a silicon carrier, which consists of two Si chips that are bonded together with evaporated AuSn-solder. There are micro fins and channels fabricated in the Si chip and form the embedded cooling layer after bonding. The embedded cooling layer is connected with an inlet and an outlet to form a fluidic path for heat transfer enhancement. Besides, in the silicon carrier, there are through silicon vias (TSVs) with metal film on sidewall for electrical interconnection. Two or more carriers can then be stacked together with a silicon interposer in between to make up of a stacked cooling module for high power heat dissipation. The advantage of this 3-D stacking method is that it provides a method of simultaneously realizing electrical interconnection and fluidic path and it can extract heat from the constraints of 3-D silicon module chips to surface without external liquid circulation. 相似文献
60.
A study was conducted to compare the bioavailability of a generic product of atenolol (Normaten FC) with the innovator product, Tenormin. Twelve healthy adult volunteers participated in the study conducted according to a randomized, two-way crossover design. The preparations were compared using area under the plasma concentration-time curve AUC0-infinity, peak plasma concentration Cmax, and time to reach peak plasma concentration Tmax. No statistically significant difference was obtained between the Tmax values and the logarithmic transformed AUC0-infinity and Cmax values of the two products. Moreover, the 90% confidence interval for the ratio of the logarithmically transformed AUC0-infinity values of Normaten FC over those of Tenormin was found to lie between 0.82 and 0.98, while that of the logarithmically transformed Cmax values was between 0.82 and 1.09, both being within the bioequivalence limit of 0.80-1.25. The values of elimination half-life t1/2 between the two products were also found comparable and not significantly different statistically. The t1/2 values obtained in our study were slightly longer than those reported in the literature for other population groups. 相似文献