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951.
N- and p-MOSFETs have been fabricated in strained Si-on-SiGe-on-insulator (SSOI) with high (15-25%) Ge content. Wafer bonding and H-induced layer transfer techniques enabled the fabrication of the high Ge content SiGe-on-insulator (SGOI) substrates. Mobility enhancement of 50% for electrons (with 15% Ge) and 15-20% for holes (with 20-25% Ge) has been demonstrated in SSOI MOSFETs. These mobility enhancements are commensurate with those reported for FETs fabricated on strained silicon on bulk SiGe substrates  相似文献   
952.
Twenty-two cases of partial or wholly composed clear-cell thyroid tumors were reviewed to differentiate between a primary nodule and metastatic clear-cell renal carcinoma in the thyroid. Pathological reevaluation of HE-stained specimens, immunohistochemical observation using anti-thyroglobulin (TG) antibody, and periodic acid-Schiff (PAS) staining were performed. The pathological characteristics in metastases from the kidney have a greater tendency to demonstrate a strikingly clear cytoplasm with small nuclei, rich vascularization, and a trabecular arrangement of tumor cells than do primary thyroid cases. The immunohistochemical TG staining in conjunction with PAS staining for the recognition of follicular colloid could provide much more reliable information of primary cases compared to that using TG staining alone. Clinically, in primary cases, the female:male ratio is substantially higher while the mean age is lower than in metastatic cases reflecting differentiated thyroid carcinoma. In conclusion, immunohistochemical staining for TG with PAS staining for the recognition of follicular colloid proved to be the most sensitive method for identifying primary clear cell thyroid tumors. In addition, a careful assessment of past and/or present kidney disorders to rule out metastatic renal cell carcinoma is advisable. Age, gender, and physiological findings are also informative when differentiating between them.  相似文献   
953.
蓝牙技术与无线火灾自动报警系统   总被引:1,自引:1,他引:0  
针对现阶段有线火灾自动报警系统的缺陷 ,通过对“蓝牙”技术的性能描述及其与红外无线技术的分析比较 ,提出了运用蓝牙技术将火灾自动报警系统连接组建成固定网络的远距离特别连接设备群 ,使火警信号在两个或多个电子设备之间通过无线传输进行信息交换和交叉操作的设想  相似文献   
954.
Surface passivation technology plays an important role, especially in E-mode pHEMTs applications, and a new passivation technology has been proposed in this study. This novel benzocyclobutene (BCB) passivation layer takes advantage of the low dielectric permittivity (2.7) and a low loss tangent (0.0008). In this letter, we not only suppress the gate-to-drain leakage current but also improve the device power performance under a high input power swing by using a BCB passivation layer. The passivated 1.0 μm-long gate pHEMTs exhibit a better off-state performance than the unpassivated ones. The maximum output power under a 2.4-GHz operation is 118 mW/mm, with a linear power gain of 11.1 dB and a power-added efficiency is 60%  相似文献   
955.
Knoop indentation microhardness measurements were made on the (10 1)cleavage planes of three structurally related single crystals: calcite, dolomite and magnesite. The effective-resolved-shear-stress concept was applied to explain the observed microhardness profiles. The deformation mechanisms of calcite, which involved both twinning and dislocation slip, were considered. Finally, the indentation load/size effect on the microhardness was addressed by both forms of Meyer's Law.  相似文献   
956.
A BiCMOS technology has been developed that integrates a high-performance self-aligned double-polysilicon bipolar device into an advanced 0.25 μm CMOS process. The process sequence has been tailored to allow maximum flexibility in the bipolar device design without perturbation of the CMOS device parameters. Thus, n-p-n cutoff frequencies as high as 60 GHz were achieved while maintaining a CMOS ring oscillator delay per stage of about 54 ps at 2.5 V supply comparable to the performance in the CMOs-only technology. BiCMOS and BiNMOS circuits were also fabricated. BiNMOS circuits exhibited ≈45% delay improvement compared to CMOS-only circuits under high load conditions at 2.5 V  相似文献   
957.
刘以gao 《电讯技术》1991,31(3):15-26
本文讨论具有帧结构的高速数字流的帧同步提取技术。从帧同步器方案的最佳参数设计出发,以误码性能为主要目标,本文较系统地提出了一套有关帧同步过程的基本概念和分析方法,并导出在各种情况下的统计关系及重要结论。本文还以美国陆地卫星TM数据流为例,特别阐述了复帧结构情况下的帧同步提取及其最佳参数设计。  相似文献   
958.
The source-drain series resistances of devices contacted by a local interconnection technology utilizing polysilicon strapped with selective CVD tungsten were measured and compared to predictions obtained using a theoretical model. Asymmetrical devices in which the local interconnections were intentionally misaligned to the gate were fabricated to study the effects of misalignment on device characteristics. Experiments indicate that the technology is quite forgiving to the misalignment between the gate and the local interconnection  相似文献   
959.
Owing to the overlapping absorption bands of hemoglobin and bilirubin, spectrophotometric determination of plasma free hemoglobin has been plagued by the interference of bilirubin when the latter is present in significant concentrations. To resolve this problem, bilirubin oxidase from Myrothecium verrucaria has been used to remove bilirubin in icteric samples. The enzyme converts bilirubin to biliverdin and eliminates its absorption in the 400 nm region. The absorbance of hemoglobin at 415 nm after Allen baseline correction is used to quantify its concentration. Intra-assay precision of this method on a sample containing 200 mg/L of free hemoglobin and 200 mg/L of bilirubin is 3.1 percent (n = 10), while the between-run precision is 3.8 percent (n = 10). Accuracy studies with samples containing 200 mg/L of bilirubin yielded a straight line: y = 0.90x + 2.31, Sy.x = 3.3, r = 0.99. These results demonstrate that this method can be used to determine free hemoglobin in icteric specimens.  相似文献   
960.
PURPOSE: The purpose of this study was to define the relationship between lipoprotein (LP) lipid concentration and composition and the distribution of cyclosporine (CSA) in human plasma. METHODS: 3H-CSA LP distribution was determined in normolipidemic human plasma that had been separated into different LP and lipoprotein-deficient plasma (LPDP) fractions by either affinity chromatography coupled with ultracentrifugation, density gradient ultracentrifugation or fast protein liquid chromatography. 3H-CSA LP distribution (at a concentration of 1000 ng/ml) was also determined in patient plasma samples with defined dyslipidemias. Furthermore, 3H-CSA LP distribution was determined in patient plasma samples of varying LP lipid concentrations. Following incubation, the plasma samples were separated into their LP and LPDP fractions by sequential phosphotungistic acid precipitation in the dyslipidemia studies and by density gradient ultracentrifugation in the specific lipid profile studies and assayed for CSA by radioactivity. Total plasma and lipoprotein cholesterol (TC), triglyceride (TG) and protein (TP) concentrations in each sample were determined by enzymatic assays. RESULTS: When the LP distribution of CSA was determined using three different LP separation techniques, the percent of CSA recovered in the LP-rich fraction was greater than 90% and the LP binding profiles were similar with most of the drug bound to plasma high-density (HDL) and low-density (LDL) lipoproteins. When 3H-CSA was incubated in dyslipidemic human plasma or specific patient plasma of varying LP lipid concentrations the following relationships were observed. As the very low-density (VLDL) and LDL cholesterol and triglyceride concentrations increased, the percent of CSA recovered within the VLDL and LDL fractions increased. The percent of CSA recovered within the HDL fraction significantly decreased as HDL triglyceride concentrations increased. The percent of CSA recovered in the LPDP fraction remained constant except in hypercholesterolemic/hypertriglyceridemic plasma where the percent of CSA recovered decreased. Furthermore, increases in VLDL and HDL TG/TC ratio resulted in a greater percentage of CSA recovered in VLDL but less in HDL. CONCLUSIONS: These findings suggest that changes in the total and plasma LP lipid concentration and composition influence the LP binding of CSA and may explain differences in the pharmacological activity and toxicity of CSA when administered to patients with different lipid profiles.  相似文献   
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