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991.
Ibrarullah DK Agarwal WA Baijal G Choudhuri VK Kapoor 《Canadian Metallurgical Quarterly》1993,14(2):68-72
Four cases (one asymptomatic and three symptomatic) of solitary non-parasitic cysts of the liver are presented. The asymptomatic cysts was an incidental finding at laparotomy. The other three patients presented with abdominal distension, jaundice and malignant transformation respectively. Management of these patients has been discussed and the literature reviewed. 相似文献
992.
A dispersion-compensated optical fiber is proposed for optical soliton propagation. The scheme is studied by a variational approach. Numerical analyses show that the proposed scheme can retain the soliton property for a much longer distance than normal systems. It is shown that, after 48 km, the pulsewidth in the proposed system remains similar to the initial pulsewidth, whereas in the normal system, the pulsewidth has already reached 10 times the initial value. It is demonstrated that significant improvements in soliton propagation characteristics can be achieved by properly cascading fibers with different degrees of group velocity dispersion in finite steps 相似文献
993.
994.
The deposition of silicon nitride thin films by the reactive sputtering of elemental silicon in a nitrogen/argon plasma has been investigated. The composition of the thin films has been examined using infra-red reflectance, X-ray photoelectron and Auger electron spectroscopies and spark source mass spectrometry. Oxygen has been found to be a major contaminant in these sputter deposited films, the oxygen concentration depending on the ambient gas pressure. The use of the silicon oxy-nitride films as annealing encapsulants for the activation of silicon ion implanted semi-insulating gallium arsenide has also been investigated. 相似文献
995.
Petroleum, coals and shale oils are the most complex mixtures in nature, containing thousands of components. They require sophisticated analytical technologies for correlation and prediction of the properties/performance of the products as well as the processability of the feeds. After decades of endeavor and development, the analyses of heavy fractions of these hydrocarbon resources remain to be challenges. Among a variety of analytical techniques, mass spectrometry provides unique capabilities for looking into detailed composition down to molecular-level. In mass spectrometry, various ionization techniques have been developed for a wide range of molecular information. Its coupling with chromatography greatly enhances the separation power and specificity of components in complex mixtures. Petroleome, which consists of ~40,000 chemical constituents, are now achievable using ultra-high resolution Fourier-transform ion cyclotron resonance (FT-ICR) spectroscopy with advanced data analysis. Another challenge is to interpret overwhelming analytical data for its physical and chemical significance. Chemometrics have been used as a data mining tool to identify key species that would mostly affect the overall properties of feed and products. Recent development in molecular modeling provides us with abilities for prediction of effectiveness of refining processes from the molecular composition data. This presentation will give an overview of the analytical, particularly mass spectrometric, and modeling approaches to obtain relevant molecular data or information for further understanding of the product quality and the prediction/assessment of petroleum process effectiveness. 相似文献
996.
Ta-Hsin Chou Kuei-Yuan Cheng Tien-Li Chang Chia-Jen Ting Hsiu-Chen Hsu Chin-Jyi Wu Jen-Hui Tsai Tzn-Yu Huang 《Microelectronic Engineering》2009,86(4-6):628-631
The cholesteric liquid crystals display (ChLCD) is one kind of reflective liquid crystal display, the antireflective layer on its transparent conduction oxides (TCO) film is needed for good contrast and color performance. In this study, the finite difference time domain (FDTD) simulation and nanoimprinting fabrication of AR structures on the TCO film are developed. Finally, the reflectance of AR structures on TCO film is just half of the original film, and this result is useful for the reflective ChLCD product commercialized in the future. 相似文献
997.
998.
As industrial technology gets more mature, a single fiber can offer more and more wavelengths. However, it also results in
a large amount of switching ports at optical cross-connects (OXCs). Certainly, it is expected that higher and higher complexity
is inevitable to control and manage such large OXCs. In this paper, we study the dynamic wavelength assignment problem in
waveband switching (WBS) networks composed of multi-granular OXCs (MG-OXCs). Moreover, in order to relax the wavelength continuity
constraint on lightpath establishments, each MG-OXC node is equipped with a certain number of converters. To efficiently minimize
the extra port consumption and utilize wavelength converters, we proposed an online wavelength assignment algorithm named
Least Weighted Configuration Cost (LWCC). For a new request, LWCC first adopts fixed routing and then exploits the layered-graph approach and a new cost function
for edge weight assignment to determine adequate wavelength(s). The performance metrics of interest include both blocking
performance and converter utilization. Numerical results show that LWCC is superior in waveband grouping and therefore results
in significant performance gain in terms of blocking probability.
相似文献
Ching-Fang HsuEmail: |
999.
Chen‐Han Chien Ching‐Kun Chen Fang‐Ming Hsu Ching‐Fong Shu Pi‐Tai Chou Chin‐Hung Lai 《Advanced functional materials》2009,19(4):560-566
A highly efficient blue‐light emitter, 2‐tert‐butyl‐9,10‐bis[4′‐(diphenyl‐phosphoryl)phenyl]anthracene (POAn) is synthesized, and comprises electron‐deficient triphenylphosphine oxide side groups appended to the 9‐ and 10‐positions of a 2‐tert‐butylanthracene core. This sophisticated anthracene compound possesses a non‐coplanar configuration that results in a decreased tendency to crystallize and weaker intermolecular interactions in the solid state, leading to its pronounced morphological stability and high quantum efficiency. In addition to serving as an electron‐transporting blue‐light‐emitting material, POAn also facilitates electron injection from the Al cathode to itself. Consequently, simple double‐layer devices incorporating POAn as the emitting, electron‐transporting, and ‐injecting material produce bright deep‐blue lights having Commission Internationale de L'Eclairage coordinates of (0.15,0.07). The peak electroluminescence performance was 4.3% (2.9 cd A?1). For a device lacking an electron‐transport layer or alkali fluoride, this device displays the best performance of any such the deep‐blue organic light‐emitting diodes reported to date. 相似文献
1000.
Wen‐Wen Huang Yu‐Jen Chiu Ming‐Jen Fan Hsu‐Feng Lu Hsiu‐Feng Yeh Kun‐Hong Li Po‐Yuan Chen Jing‐Gung Chung Jai‐ Sing Yang 《Molecular nutrition & food research》2010,54(11):1585-1595
Kaempferol is a natural flavonoid. Previous studies have reported that kaempferol has anti‐proliferation activities and induces apoptosis in many cancer cell lines. However, there are no reports on human osteosarcoma. In this study, we investigate the anti‐cancer effects and molecular mechanisms of kaempferol in human osteosarcoma cells. Our results demonstrate that kaempferol significantly reduces cell viabilities of U‐2 OS, HOB and 143B cells, especially U‐2 OS cells in a dose‐dependent manner, but exerts low cytotoxicity on human fetal osteoblast progenitor hFOB cells. Comet assay, DAPI staining and DNA gel electrophoresis confirm the effects of DNA damage and apoptosis in U‐2 OS cells. Flow cytometry detects the increase of cytoplasmic Ca2+ levels and the decrease of mitochondria membrane potential. Western blotting and fluorogenic enzymatic assay show that kaempferol treatment influences the time‐dependent expression of proteins involved in the endoplasmic reticulum stress pathway and mitochondrial signaling pathway. In addition, pretreating cells with caspase inhibitors, BAPTA or calpeptin before exposure to kaempferol increases cell viabilities. The anti‐cancer effects of kaempferol in vivo are evaluated in BALB/cnu/nu mice inoculated with U‐2 OS cells, and the results indicate inhibition of tumor growth. In conclusion, kaempferol inhibits human osteosarcoma cells in vivo and in vitro. 相似文献