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21.
Kuo‐Hsiung Wang Tzong‐Ming Wu Yeng‐Fong Shih Chien‐Ming Huang 《Polymer Engineering and Science》2008,48(9):1833-1839
The water bamboo husk is one of major agricultural wastes in Taiwan. In this study, the powder obtained from the water bamboo husk was added to poly(lactic acid) (PLA) to form novel reinforced biodegradable composites. Morphologies, mechanical properties, and heat resistance of these water bamboo powder reinforced composites were investigated. The results indicate that the char yields were increased as plant powder was incorporated to PLA. In addition, the mechanical properties were also enhanced due to the addition of powders. The increments of storage moduli of PLA were about 50–200%. Moreover, the increments of loss moduli of PLA were about 70–200%. On the other hand, the Tg of PLA was slightly decreased by the addition of powder, and this may improve the brittle characteristics of PLA. Furthermore, this type of reinforced PLA would be more environmental friendly than the artificial additive‐reinforced one. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers 相似文献
22.
Raybon G. Young M.G. Koren U. Miller B.I. Chien M. Zirngibl M. Dragone C. Froberg N.M. Burrus C.A. 《Electronics letters》1995,31(14):1147-1149
Five wavelength multiplexed pulse streams are generated in an integrated 16×1 laser modulator array by sinusoidally driving five of the potential 16 electroabsorption modulators. At a repetition rate of 2.5 GHz, near transform-limited pulses spaced in wavelength over 7.6 nm are observed. Pseudorandom coding of one channel is achieved by applying an electrical RZ data signal to the modulator 相似文献
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24.
在现有方案的基础上,通过分析超椭圆曲线双线性对和基于身份的特点,给出了一个改进的基于身份的一次性盲公钥方案。该方案由用户和可信中心共同完成用户密钥的生成,克服了密钥托管问题,避免了由可信中心进行密钥管理所产生的安全隐患。新构造的方案能够抵抗伪造性攻击,具有不可欺骗性,又保证了一次性盲公钥的独立性,是安全可靠的。而且方案中用户在通讯时可以使用不同的公钥,解决了Internet通信中的匿名认证问题,实现了用户隐私的有效保护。 相似文献
25.
Cyclic hot corrosion conducted on Haynes 230 at temperatures of 871 and 1093 C indicated that catastrophic corrosion occurred. The corrosion rate was related to the high content of tungsten and chromium in the alloy. The concept of basic and acid fluxing was applied to explain the dissolution of the protective film of Cr2O3 and volatile WO3 by an Na2SO4-rich liquid due to the formation of Na2CrO4 and Na2WO4. As the basic melts were acidified by continuously consuming oxygen ions, plate-like crystals of Cr2O3 were precipitated on the free surface by conversion from Na2CrO4. Acid fluxing was achieved by the refractory oxide, WO3, consuming oxygen ions. The presence of sulphur suppressed the diffusion of chromium outward to form protective Cr2O3. Internal chromium-rich sulphide particles were observed. It was suggested that at very lowP
O2, sulphur reacted with chromium to form CrS initially. As oxygen penetrated through the porous layer, the CrS was oxidized internally to Cr2O3. 相似文献
26.
Fu KS Chien YT Cardillo GP 《IEEE transactions on pattern analysis and machine intelligence》1986,(3):313-326
This paper presents the dynamic programming approach to the design of optimal pattern recognition systems when the costs of feature measurements describing the pattern samples are of considerable importance. A multistage or sequential pattern classifier which requires, on the average, a substantially smaller number of feature measurements than that required by an equally reliable nonsequential classifier is defined and constructed through the method of recursive optimization. Two methods of reducing the dimensionality in computation are presented for the cases where the observed feature measurements are 1) statistically independent, and 2) Markov dependent. Both models, in general, provide a ready solution to the optimal sequential classification problem. A generalization in the design of optimal classifiers capable of selecting a best sequence of feature measurements is also discussed. Computer simulated experiments in character recognition are shown to illustrate the feasibility of this approach. 相似文献
27.
To maintain competitive advantages, semiconductor industry has strived for continuous technology migrations and quick response to yield excursion. As wafer fabrication has been increasingly complicated in nano technologies, many factors including recipe, process, tool, and chamber with the multicollinearity affect the yield that are hard to detect and interpret. Although design of experiment (DOE) is a cost effective approach to consider multiple factors simultaneously, it is difficult to follow the design to conduct experiments in real settings. Alternatively, data mining has been widely applied to extract potential useful patterns for manufacturing intelligence. However, because hundreds of factors must be considered simultaneously to accurately characterize the yield performance of newly released technology and tools for diagnosis, data mining requires tremendous time for analysis and often generates too many patterns that are hard to be interpreted by domain experts. To address the needs in real settings, this study aims to develop a retrospective DOE data mining that matches potential designs with a huge amount of data automatically collected in semiconductor manufacturing to enable effective and meaningful knowledge extraction from the data. DOE can detect high-order interactions and show how interconnected factors respond to a wide range of values. To validate the proposed approach, an empirical study was conducted in a semiconductor manufacturing company in Taiwan and the results demonstrated its practical viability. 相似文献
28.
Yuan‐Hsiang Yu Chien‐Chih Jen Hsiu‐Ying Huang Pei‐Chi Wu Chao‐Cheng Huang Jui‐Ming Yeh 《应用聚合物科学杂志》2004,91(6):3438-3446
A series of heterocyclically conjugated polymer–clay nanocomposite (PCN) materials that consisted of organic poly(3‐hexylthiophene) (P3HT) and inorganic montmorillonite (MMT) clay platelets were prepared by in situ oxidative polymerization with FeCl3 as an oxidant. The as‐synthesized PCN materials were characterized by Fourier transform infrared (FTIR) spectroscopy, wide‐angle powder X‐ray diffraction (WAXRD), and transmission electron microscopy (TEM). The effects of the material composition on the anticorrosion, gas barrier, thermal stability, flammability, mechanical strength, and electrical conductivity properties of the P3HT and PCN materials were studied by electrochemical corrosion measurements, gas‐permeability analysis (GPA), thermogrametric analysis (TGA), limiting oxygen index (LOI) measurements, dynamic mechanical analysis (DMA), and a four‐point probe technique, respectively. The molecular weights of extracted and bulk P3HT were determined by gel permeation chromatography (GPC) with THF as an eluant. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3438–3446, 2004 相似文献
29.
Su‐Hsia Lin Hsiang‐Chien Kao Shih‐Hung Huang Ruey‐Shin Juang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(2):168-174
The equilibrium and kinetics of solvent extraction of Cu2+ from aqueous solutions containing equimolar EDTA with Aliquat 336 in n‐decanol and kerosene at 298 K were investigated. The concentrations of Cu2+ (8–50 mol m?3), Cl? (5–60 mol m?3), and Aliquat 336 (20–100 mol m?3) were varied. A semi‐empirical model with three parameters was proposed to describe the equilibrium behavior, in which the non‐idealities in both aqueous and organic phases were considered. Over the ranges studied, the model agreed reasonably well with the experimental data (standard deviation, 15%). The forward and backward reaction rate constants were determined as (5.31 ± 0.16)×10?6 m9/4 mol?3/4 s?1 and (2.62 ± 0.09)×10?7 s?1, respectively, at 298 K. An interfacial reaction mechanism was proposed, which revealed that the reaction between the chelated anions and trimeric amine molecules at the interface was rate limiting. The derived rate laws were consistent with the experimental results. © 2002 Society of Chemical Industry 相似文献
30.
In this article, we proposed a rapid and continuous process for the production of nanoporous coatings for functional applications.
Experiments following two statistical designs were implemented to screen and investigate the spraying parameters’ effects
on coating crystallinity and porosity in order to gain a better understanding. The spraying standoff distance, solution flow
rate and power were identified as having significant effects on coating porosity and crystallinity. The result yielded a peculiar
microstructure comprised of interpenetrating pores and layered structures with embedded pores. A deposition mechanism was
postulated to explain this microstructure. Ethanol gas sensors that are constructed from the coatings had comparable sensitivities
to those reported in the literature for thick-film coatings and had a maximum sensitivity near 200 °C.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献