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71.
Taylor G.W. Lebby M.S. Chang T.Y. Gnall R.N. Sauer N. Tell B. Simmons J.G. 《Electronics letters》1987,23(2):77-79
A new form of FET has been demonstrated in the GaAs/AlGaAs material system. Designated the HFET, it has shown a transconductance of 500mS/mm at 300K for a nominal Lg =2?m and a drain current of 430mA/mm. The conduction occurs in an inversion channel at the heterointerface. 相似文献
72.
A complementary inverter configuration based on two new heterostructure field-effect devices is proposed. The FETs are fabricated in a common substrate grown by molecular-beam epitaxy. The devices rely on the formation of inversion layers at heterojunction interfaces. 相似文献
73.
Robert Simmons 《中国橡胶》2010,26(2):13-16
一、全球轮胎市场发展趋势
对于轻型汽车(LV,包括轿车胎和轻型商用车胎)和中重型载重卡车(M/H CV)来说,国内生产总值(GDP)的增长是其需求增长的动力。金融危机和经济衰退使欧美等发达国家GDP减少.导致全球轮胎销售额的大幅下降,其中原配轮胎(OE)市场受到的影响更为严重。通常,中重型载重卡车轮胎中,原配胎销售额占其总销售额的20%;轻型汽车轮胎中,原配胎占25%。 相似文献
74.
Krometis LA Characklis GW Simmons OD Dilts MJ Likirdopulos CA Sobsey MD 《Water research》2007,41(2):506-516
Association with particles in the water column can have a significant impact on microbial fate and transport. This study analyzed multiple stormwater samples taken throughout the duration of three separate storms (at two different sites) to evaluate the fraction of microbes partitioning to denser "settleable" particles and to examine how partitioning behavior varied over the course of a storm. Intra-storm sampling also allowed for estimates of microbial loading rates (both total and particle-associated) and cumulative storm-induced microbial load. Five different indicator organisms were examined, with the fraction of microbes associated with settleable particles assessed via a calibrated centrifugation method. Partitioning behavior varied across microorganism type, with an average of 40% of fecal coliforms, Escherichia coli, and enterococci associating with settleable particles, compared to approximately 65% of Clostridium perfringens spores and only 13% of total coliphage. Partitioning remained fairly constant for each type of organism throughout storm events. Nonetheless, higher concentrations of both settleable particles and microbes entering the water column soon after the onset of a storm led to higher loading rates of settleable microbes in the storm's earliest stages, a trend that could have important implications for the design of stormwater management structures (e.g., detention basins). Estimates of cumulative storm-induced microbial loading suggested that one day's worth of storm loading can be the equivalent of months, or even years, of dry-weather loading. 相似文献
75.
Effects of Microbial Transglutaminase on the Wheat Proteins of Bread and Croissant Dough 总被引:6,自引:0,他引:6
J.A. Gerrard S.E. Fayle P.A. Brown K.H. Sutton L. Simmons I. Rasiah 《Journal of food science》2001,66(6):782-786
ABSTRACT: Transglutaminase is a crosslinking enzyme that is finding increasing use in foods, yet the molecular changes responsible for its effects are not fully understood. Proteins were extracted from bread and croissant doughs that had been treated with transglutaminase and compared to those from control doughs by size exclusion high performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis. Transglutaminase increased the amount of protein extracted in the gliadin fraction in both bread and croissant doughs. In croissant doughs, a corresponding decrease in the protein extracted in the albumin to globulin fraction was seen. In each case, crosslinking of the high molecular weight glutenins was observed. The possible role of each of these changes on the functional properties of baked products is discussed. 相似文献
76.
Journal bearings are an important design option, particularly appropriate for high-speed rotating machinery applications. This paper presents results from an extensive program of experimental work with a 200 mm, five-shoe, tilting-pad bearing of this type. The tilting pads were fitted with offset pivots; this is in contrast to most previous work which has concentrated on bearings with pads which have centrally mounted pivots. The new results obtained for the offset pivot pad bearing are compared with recently published, equivalent results for the same bearing filled with center pivot pads. A substantial temperature reduction in bearing temperature is revealed for the offset pivot case. 相似文献
77.
The ability of 73 male bullfrogs (Rana catesbeiana) to detect single mistuned harmonics in an otherwise periodic signal was studied. Bullfrogs in their natural environment were presented with playbacks of synthetic signals, resembling their species advertisement calls, that differed in the frequency of 1 harmonic component (out of 22). There were significant differences in the number and latency of the males' evoked vocal responses to these stimuli, suggesting that males were sensitive to the differences between the sounds. Differences in envelope shape (rate and depth of amplitude modulation) produced by the harmonic mistunings may underlie the differences in response. Frogs, like birds and humans, can discriminate sounds on the basis of harmonic structure, indicating that this is a general perceptual trait shared among vertebrates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Straits-Tr?ster Kristy A.; Brancu Mira; Goodale Bob; Pacelli Sheryl; Wilmer Charlotte; Simmons Erin M.; Kudler Harold 《Canadian Metallurgical Quarterly》2011,3(3):283
Meeting the mental health needs of Veterans returning from recent deployment requires the coordinated effort of partnerships across Department of Defense (DoD), Department of Veterans Affairs (VA), and state and local communities. Although the proportion of Veterans of Iraq and Afghanistan who have accessed VA health care has grown, the majority of these new combat Veterans have yet to present for VA care. The stigma associated with reporting a deployment-related mental health problem may be one factor in this, but access to treatment may also be an important concern among the one third of American Veterans who live in rural or highly rural areas. As these Veterans are more likely to present to a primary care, faith-based or mental health provider in their own community, partnerships between community providers, DoD, and VA are of critical importance in ensuring appropriate care, regardless of treatment setting. In an effort to improve services and access to services, especially to rural Veterans, an educational public health initiative was created to educate community providers about military culture, deployment-related mental health issues, VA resources, and evidence-based treatments. We describe the development, dissemination and evaluation of this initiative, as well as lessons learned for future similar endeavors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
79.
80.
The aim of this study was to determine the prognostic value of single and paired measurements of serum concentrations of human chorionic gonadotrophin (HCG) for successful pregnancy following in-vitro fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG concentrations 15 and 22 days after IVF or TET in 198 conception cycles. Cut-off values of serum HCG were determined by a receiver operating characteristic (ROC) curve. On the basis of single HCG samples on day 15 (HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the sensitivity was 71% and the specificity was 77%. The positive predictive value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%, while the negative predictive rate (HCG15 < 150 mIU/ml indicating an abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy. However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio < 15, there was an 84% chance of an abnormal pregnancy. We conclude that a single HCG15 determination combined with the ratio of HCG22 to HCG15 has a higher diagnostic accuracy for prediction of pregnancy outcome than either analysis alone. 相似文献