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91.
Baoping Wang Zhongping Huang Sin J.K.O. Poon V.M.C. Yongming Tang Chen Wang Kunxing Xue Linsu Tong 《Electron Device Letters, IEEE》1999,20(12):621-623
In this paper, a new emitter-sharpened double-gate race-track-shaped field emitter structure is reported. The race-track-shaped edge emission with double-gate control is used to provide high uniformity FEAs over a large area without the need of expensive submicron technology. In order to minimize the gate current, which is detrimental to the field emitter performance, an emitter-sharpened structure is used. Experimental results show that the turn-on voltage of the emitter-sharpened double-gate structure is 45 V, which is 60% smaller than that of the single-gate structure (110 V). Furthermore, the gate current of the emitter-sharpened double-gate structure is 7 times and 15 times smaller than that of the nonemitter-sharpened double-gate structure and the single-gate structure, respectively 相似文献
92.
Grain subdivision and recrystallization in oligocrystalline tantalum during cold swaging and subsequent annealing 总被引:1,自引:0,他引:1
Hugo R. Z. Sandim Angelo F. Padilha Valerie Randle Wolfgang Blum 《International Journal of Refractory Metals and Hard Materials》1999,17(6):431-435
A coarse-grained ingot of high-purity tantalum was deformed by swaging at room temperature to a strain of 1.28. During annealing at 900°C for 30 min two neighboring grains were observed to behave quite differently. Electron backscattering diffraction (EBSD) results show noticeable differences in terms of the misorientations developed in both grains. The grain developing larger misorientations recrystallized much more readily than the other. The result is interpreted in terms of the differences in grain subdivision into strongly misoriented regions. 相似文献
93.
94.
This study was performed to examine the anti-fibrotic activity of HV-P411, an herbal mixture of seeds of Vitis vinifera, Schisandra chinensis and Taraxacum officinale extract, against carbon tetrachloride (CCl4)-induced liver fibrosis. Hepatic fibrosis was induced by intraperitoneal injection of CCl4 (0.5 ml/kg, twice weekly) for 8 weeks. Rats were treated orally with HV-P411 at 50, 100, 200, and 400 mg/kg once a day. After chronic exposure to CCl4, the levels of hydroxyproline were markedly increased; these were significantly reduced by HV-P411 at all dose levels. The level of serum aminotransferases and lipid peroxidation were increased after the CCl4 treatment, while reduced glutathione was decreased. These changes were attenuated by HV-P411. In addition, HV-P411 attenuated CCl4-induced raised serum concentration of transforming growth factor-β1, and the levels of matrix metalloprotease-2 and tissue inhibitor of metalloprotease-1 mRNAs. Our results suggest that HV-P411 may prevent liver fibrosis by modulating fibrogenesis and fibrolysis. 相似文献
95.
William T. Riley Steven C. Carson Norman Martin Albert Behar Valerie L. Forman-Hoffman Albert Jerome 《Computers in human behavior》2005,21(6):1005-1018
This study sought to evaluate the feasibility of a researcher configurable self-monitoring program. An initial prototype of the program was developed as a Windows-based drag and drop flow chart interface for the researcher to construct the self-monitoring or diary protocol to be scheduled and displayed to the subject on a Pocket PC. The usability of the desktop researcher interface was evaluated in a small sample of medication trial researchers whose ratings of the prototype were generally positive and provided directions for improvement. The subject interface was then evaluated in an “analog” drug trial of 49 smokers using nicotine gum. These subjects were randomly assigned to either paper-based log or Pocket PC self-monitoring for 3 weeks. Pocket PC subjects were significantly more compliant than the log subjects on recording in the second (65% vs. 39%) and third (69% vs. 39%) weeks of the trial but did not differ from the log condition on total recording entries, likely due to the restrictions on retrospective recording in the Pocket PC program. This study provides support for the feasibility of a researcher configurable electronic diary system which should substantially reduce the programming barriers to electronic self-monitoring and increase the use of real-time monitoring in clinical and research venues. 相似文献
96.
Agusti Sin B. El Montaser Philippe Odier F. Weiss 《Journal of the American Ceramic Society》2002,85(8):1928-1932
The acrylamide gelification process is a fast, inexpensive, reproducible, and easily scaled up chemical method for obtaining nanopowders of BaZrO3 that can be used for sintering crucibles and many electronic applications. This method enables the production of 100 g of high-purity powders in one run, using simple laboratory equipment and low-cost raw materials. The gelification process, synthesis temperature, and gas conditions required for obtaining high-quality powders were the subjects of the present study. Fine powders were sintered to full density at 1450°C, making the fabrication of BaZrO3 crucibles possible for many laboratories. 相似文献
97.
David C. T. Or P. T. Lai J. K. O. Sin P. C. K. Kwok J. P. Xu 《Microelectronics Reliability》2003,43(1):163-166
Silicon MOS capacitors fabricated solely by low-temperature processes (under 600 °C) are treated with nitridation using N2O or NO plasma. Their properties are investigated at room temperature under high-field stress. It is found that both kinds of plasmas are effective in improving the gate-oxide hardness against stress-induced damage, which is characterized by a smaller shift in flatband voltage and smaller increase in interface states after the stress. Moreover, NO-nitrided device shows better performance than N2O-nitrided one. These results show that plasma nitridation has positive effects on the reliability of low-temperature-fabricated devices, which play an important role in flat-panel display systems on glass. 相似文献
98.
In this paper, a new hydrogenation process of poly-Si thin film for the fabrication of poly-Si thin film transistors (TFTs) is proposed. In the new approach, the hydrogenation of TFTs is performed before deposition of contact metal. N-channel and p-channel poly-Si TFTs with various channel lengths and widths were fabricated with the new and conventional processes for comparison. The results verified that the efficiency of hydrogenation has been improved remarkably by the new process. The field-effect mobility of carriers, the on state current, threshold voltage and the on/off states current ratio have been greatly improved, and the trap state density has been reduced significantly. 相似文献
99.
Recently, a model-based optimisation methodology for SBR operation has been developed and an optimal operation scenario proposed to improve N and P removal in a pilot-scale SBR. In this study, this optimal operation scenario was implemented and evaluated. The results of the implementation showed that the SBR performance was improved by approximately 50 and 40% for total nitrogen and phosphorous removal, respectively, which was better than predicted by the model. However, the long-term SBR performance was found to be unstable, particularly owing to settling problems developed after the implementation. When confronted with reality, the model used for the optimisation of the operation was found to be invalid. The model was unable to predict the nitrite build-up provoked by the optimal operation scenario. These results imply that changing the operation of an SBR system using a model may significantly change the behaviour of the system beyond the (unknown) application domain of the model. This is simply because the mechanistic models currently do not cover all the aspects of activated sludge systems, e.g. settling and adaptation of the microbial community. To further improve model-application practices, expert knowledge (not contained in the models) can be valuable and should be incorporated into model-based process optimisations. 相似文献
100.
Segregation and Marginalisation within Public Housing: The Disadvantaged in Bedok New Town,Singapore 总被引:1,自引:0,他引:1
Chih Hoong Sin 《Housing Studies》2002,17(2):267-288
This paper examines segregation within public housing in Bedok New Town, Singapore. The highly structured and regulated public housing sector, accommodating 86 per cent of the total Singapore population, provides an interesting look at the issue of 'choice' and 'constraint', and their implications for segregation. Using the index of dissimilarity to measure evenness of distribution and the P* index to measure social interaction and isolation, the data show that lower-income members of Indian ethnic background had become more segregated between 1980 and 1990. The eligibility criteria and allocation procedures pertaining to public housing help channel certain groups of residents into a narrow array of housing types in strictly defined locations. Particular socio-demographic features of lower-income Indians, coupled with their numerical inferiority, leads to a weak position within the housing market. The issue of constrained choice is especially relevant for this group of public housing residents. 相似文献