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71.
功能看点:65536色TFT液晶屏、64和弦铃声、CCD型摄像头、有声视频拍摄(10秒/段,3GPP格式)、红外、录音(30秒/段,可设置为铃声)、全屏来电大头贴等。 相似文献
72.
Kane B.C. Geis L.A. Wyatt M.A. Copeland D.G. Mogensen J.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(9):1656-1668
As BiCMOS IC technology continues to advance in scaling and performance, new applications are continually enabled. One such concept is a smart phased array system on a chip (SoC). The combination of high-performance SiGe heterojunction bipolar transistor (HBT) bipolar devices, well-characterized RF/analog passive components, and dense CMOS digital technology provides the capability to create large multielement, electronically tunable phased arrays with onboard processing intelligence, inside a single die. This SoC will have superior characteristics of lower cost, weight, and size as compared to the large multichip, multitechnology, and multipackage systems in deployment today. Furthermore, using reconfigurable logic and embedded memory, this SoC has the advantage of dynamic software and digital signal processing engine updates, without expensive redesigns of the chip. This publication will describe the necessary ingredients to create such an SoC as well as relevant applications of smart phased arrays that require an SiGe HBT BiCMOS technology. Potential markets for this technology include communications systems, weather tracking, radio astronomy, automotive radar, cellular basestation capacity improvement, satellite and aerial resource imaging, ground-level airplane collision avoidance, as well as military tracking and guidance systems. 相似文献
73.
The importance of the expression of the autocrine growth system for bombesin-like peptides (BLPS) to the biological behavior of human lung cancer has not been determined. Three BLP receptor subtypes have been identified in human lung and lung cancer cells: gastrin-releasing peptide (GRP) receptor, neuromedin B (NMB) receptor, and bombesin receptor subtype 3 (BRS-3). The goals of this study were: (1) to determine BLP receptor subtype expression by human lung cancer cell lines by RT/PCR; (2) to evaluate possible clinical correlates of characteristics of the patients from whom the cell lines were derived with patterns of BLP receptor expression. Degenerate PCR primers were designed to amplify all known BLP receptors and yielded products from 19/20 small cell lung carcinoma (SCLC) and 12/13 non-small cell lung carcinoma (NSCLC) cell lines. GRP receptor was the most commonly expressed BLP receptor subtype, being detected in 17/20 SCLC and 11/13 NSCLC. Eleven of 20 SCLC expressed NMB receptors, and 5/20 expressed BRS-3, compared with 4/13 and 1/13, respectively, in NSCLC cell lines. Evaluation of the clinical data of the patients from whom the cell lines were derived revealed expected age, sex, smoking history and survival based on histology and stage. Patients from whom cell lines expressed GRP receptor experienced a better survival than those whose cell lines did not (367 +/- 274 days vs. 211 +/- 114 days), but the results were not statistically significant. RT/PCR analysis is a feasible, sensitive and specific means of determining BLP receptor expression in lung cancer cells and may yield prognostic information in patient tissue. 相似文献
74.
Implicit differentiation of the discretized boundary integral equations governing the conduction of heat in three dimensional (3D) solid objects, subjected to nonlinear boundary conditions, and with temperature dependent material properties, is shown to generate an accurate and economical approach for the computation of shape sensitivities. The theoretical formulation for primary response (surface temperature and normal heat flux) sensitivities and secondary response (surface tangential heat flux components and internal temperature and heat flux components) sensitivities is given. Iterative strategies are described for the solution of the resulting sets of nonlinear equations and computational performances examined. Multi-zone analysis and zone condensation strategies are demonstrated to provide substantial computational economies in this process for models with either localized nonlinear boundary conditions or regions of geometric insensitivity to design variables. A series of nonlinear sensitivity example problems are presented that have closed form solutions. Sensitivities computed using the boundary formulation are shown to be in excellent agreement with these exact expressions. 相似文献
75.
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77.
GG Schwartz MF Oliver MD Ezekowitz P Ganz D Waters JP Kane M Texter ML Pressler D Black BR Chaitman AG Olsson 《Canadian Metallurgical Quarterly》1998,81(5):578-581
Pediococcus sp. is a nonpathogenic heat-resistant spoilage organism that has been used as a test organism in milk pasteurization studies. These characteristics make this bacterium an attractive test organism to study the mode of bacterial thermal inactivation in a food pilot plant. We report here the effect of growth medium on the thermal D value of this organism in skim milk, whole liquid egg, 10% glucose solution, pineapple juice, apple juice, tomato juice, and water at 60 degrees C. Thermal inactivation was done in a submerged coil; D values were calculated from the linear portion of the survival curves by linear regression analysis. The range of D values of stationary-phase cells grown at 28 degrees C in tryptone glucose yeast extract (TGY) or tryptic soy broth (TSB) was 0.14 to 12.05 min in all heating menstrua tested. The TSB-grown cells exhibited the highest thermal resistance with skim milk and 10% glucose solution as the heating menstrua. Survival curves of the TGY-grown cells indicated the presence of a cell population heterogeneous in thermal resistance. The TSB-grown cells exhibited a cell population uniform in thermal resistance and with a lag time for thermal inactivation. When compared to TGY-grown cells, Pediococcus sp. grown in TSB showed a significant (P < 0.05) increase in D values by up to eightfold in all heating menstrua. Results from this study suggested that thermal inactivation of Pediococcus sp. was dependent on the growth medium and on the heating menstruum with respect to both pH and composition. 相似文献
78.
Recent advances in epitaxial growth have led to the prospect of artificial modification of the electronic structure or band structure of semiconductor materials. The combination of strain and quantum confinement in the valence band can lead to substantially more favorable energy dispersion relations for laser action than those existing in the natural semiconductor crystal. Numerical results are presented for a series of alloy compositions with a bandgap near the 1.55-μm optimum wavelength for optical communications. The laser threshold current and the intervalence band absorption can be significantly diminished in properly engineered band structures 相似文献
79.
Metallurgical and Materials Transactions A - 相似文献
80.
Multivalent molecules, i.e.?scaffolds presenting multiple copies of a suitable ligand, constitute an emerging class of nanoscale therapeutics. We present a novel approach for the design of multivalent ligands, which allows the biofunctionalization of polymers with proteins or peptides in a controlled orientation. It consists of the synthesis of water-soluble, activated polymer scaffolds of controlled molecular weight, which can be biofunctionalized with various thiolated ligands in aqueous media under mild conditions. These polymers were synthesized by ring-opening metathesis polymerization (ROMP) and further modified to make them water-soluble. The incorporation of chloride groups activated the polymers to react with thiol-containing peptides or proteins, and the formation of multivalent ligands in aqueous media was demonstrated. This strategy represents a convenient route for synthesizing multivalent ligands of controlled dimensions and valency. 相似文献