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101.
The characteristics of direct-tunneling gate oxide metal-oxide semiconductor field effect transistor (MOSFET)s are described. The effect of gate leakage current on MOSFET characteristics drops off as the gate length is reduced. Extremely good DC and AC performance has been realized using ultra-thin oxides down to 1.5 nm. Improved hot-carrier reliability and high oxide breakdown voltage have also been observed.  相似文献   
102.
Canadian Field Soils II. Modeling of Quartz Occurrence   总被引:1,自引:0,他引:1  
The measured mineral composition data (XRD/XRF) of 40 Canadian soils were modeled for the presence of quartz as a function of soil texture. Preliminary modeling revealed a lack of strict correlation between quartz content and mass fraction of sand. For that reason, the occurrence of quartz content was modeled as dependent on a combined fraction of sand and silt, which produced an improved correlation for all tested soils. Then, all soils were modeled separately for five assigned provinces/regions of Canada and strong correlations of quartz versus combined sand and silt fractions were obtained. Estimates of quartz content and an average thermal conductivity of other minerals were also obtained by the reverse analysis of the weighted geometric mean model applied to the experimental thermal conductivity data of saturated soils. In general, quartz estimates followed XRD/XRF data sufficiently well. The thermal conductivity of the remaining soil minerals was about 2.13 W · m?1 · K?1 on average and did not depend on the soil texture.  相似文献   
103.
Fifty-five patients suffering from refractory chronic back pain took part in a double-blind, multiple-dose, randomised, cross-over study to compare the efficacy and tolerability of a fixed-dose capsule preparation containing 500 mg paracetamol (CAS 103-90-2) and 30 mg codeine phosphate 1/2 H2O (CAS 41444-62-6) (talvosilen forte, test preparation) with a reference capsule preparation containing 50 mg tramadol hydrochloride (CAS 22204-88-2), in a regimen of two capsules 8-hourly. There were two treatment periods of up to 7 days each. Cross-over took place, without washout, at the end of 7 days, or sooner if patients were unable to tolerate the first treatment. The test preparation was at least as efficacious as the reference in the treatment of back pain (81% of patients experienced good or satisfactory pain relief). 81% of patients tolerated the test well compared to only 69% receiving the reference, as per protocol analysis. The results of this study suggest that the test product is at least as efficacious as tramadol in the treatment of patients with refractory chronic back pain, whilst being better tolerated.  相似文献   
104.
In an attempt to understand the relationship between photorepair and dark repair in Neurospora crassa, a new mutant was isolated, which showed defects in both repair processes. The new mutant, mus-38, is moderately sensitive to UV and shows imperfect photoreactivation following UV irradiation. DNA was purified from this mutant and the other UV-sensitive mutants, and analyzed for the removal of cyclobutane pyrimidine dimers (CPDs). UV-specific endonuclease-sensitive sites (ESS) completely disappeared with 1 h of photoreactivation in mus-38 DNA, although the survival recovery with photoreactivation was greatly reduced in this mutant. This suggests that the insufficient survival recovery with photoreactivation in mus-38 does not result from a failure of photo-reversal of CPDs. Removal of ESS during liquid holding (dark repair) was slower in mus-38 compared to wild type. To test the possibility that this mutant was involved in excision repair, the double mutant was made between mus-38 and mus-18, which encodes a UV-damage-specific endonuclease. CPD excision in the mus-18 null mutant was severely affected but not completely inhibited. The double mutant showed a complete loss of the excision activity and was super sensitive to UV. These results indicate that mus-38 participates in an excision pathway that is different from the mus-18 pathway. The mus-38 mutant was sensitive not only to UV but also to some chemical mutagens which make adducts on DNA. Thus, mus-38 is possibly involved in an excision-repair pathway that is related to the Saccharomyces cerevisiae RAD3 pathway.  相似文献   
105.
In a survey of mortality in 2224 rabbits of up to 12 weeks of age, drawn from 10 production units, neonatal mortality was important with 111 stillbirths and 175 deaths in the 1st week of life out of a total of 457 deaths in the whole survey. There was a low overall incidence of death from respiratory and enteric disease during the period of study.  相似文献   
106.
Here, we describe a combination approach using Two Calibration-Free Methods with reflectance near-infrared (TCFM-NIR), which involves detecting end-points for active pharmaceutical ingredients (APIs) blending by simultaneously monitoring specific NIR peak intensity of APIs and calculating moving block standard deviation (MBSD). After determining the specific NIR peak range of nicaldipine hydrochloride, conditions for TCFM-NIR were established by monitoring the differential intensity of the second peak (1136 nm) while MBSD was calculated from the NIR peak intensity between 1100 and 1150 nm. In comparison with the validated reference method of UV-VIS spectroscopy, which is particularly destructive, TCFM-NIR was found to be useful in detecting end-points for blending of nicaldipine hydrochloride. TCFM-NIR monitors two important factors for estimation of blend uniformity: API concentration, using specific NIR peak intensity for APIs, and blend homogeneity, using MBSD. Also, the conditions of TCFM-NIR were confirmed to be adequate by using Partial Least Square (PLS). Further, simultaneously monitoring these two blend uniformity factors is more useful in preventing estimation errors for nondestructive monitoring of blend homogeneity than monitoring only one factor, as with NIR spectroscopy.  相似文献   
107.
The temperature dependence of emitter-base reverse stress degradation in bipolar transistors for Bi-CMOS circuits was studied. A suitable measure of degradation in the operating temperature range was chosen after careful consideration of the fact that bipolar transistor characteristics are very sensitive to temperature changes. The worst-case temperature conditions within the transistors' operating range were determined. Degradation was found to be worst at around 50°C-a result of a tradeoff between thermal recovery from degradation and the effects of bandgap narrowing on bipolar characteristics. The recovery phenomena which had taken place after degradation were also investigated in detail  相似文献   
108.
Processing and activation of the precursor of an extracellular Streptomyces transglutaminase were achieved by using three Streptomyces proteases (SAM-P20, SAM-P26 and SAM-P45), all of which are widely distributed in Streptomyces. The use of these proteases would allow us to develop a production process for the active form of this enzyme in recombinant bacteria.  相似文献   
109.
Although volatile anesthetic is known as a cerebral vasodilator, its mechanism is not clear. The purpose of this study was to investigate effects of sevoflurane or halothane on contractions induced by high K+ and serotonin in the isolated canine basilar artery. Cylindrical segments of canine basilar artery were placed in Krebs solution oxygenated with 95% O2 and 5% CO2 at 37 degrees C. They were then constricted with cumulative administration of 10 to 60 mM KCl, or with 10(-9) to 10(-6) M serotonin and exposed to either sevoflurane or halothane at concentration of 1.0 and 2.0 MAC. Halothane and sevoflurane at concentration of 1.0 and 2.0 MAC decreased contractile responses evoked by KCl to a similar degree. The attenuation by either of the two anesthetics at concentration of 2.0 MAC were equivalent to the inhibitions by diltiazem 2 x 10(-7) M. Contractile responses to serotonin above 3 x 10(-7) M were depressed by halothane 1.0 MAC, but not by sevoflurane 1.0 MAC. Sevoflurane and halothane at concentration of 2.0 MAC decreased contractile responses evoked by serotonin at concentrations above 3 x 10(-8) M and 10(-8) M. Removal of the endothelium did not alter the response of the basilar artery contracted by serotonin to either anesthetic. These findings suggest that sevoflurane and halothane depress the voltage-dependent Ca2+ channels due to decreases of contractile responses to high K+. Our results also demonstrate that sevoflurane is a less potent vasodilator of the basilar artery contracted by serotonin than halothane.  相似文献   
110.
A numerical analysis based on adjoint formulation of unsteady forced convection heat transfer is proposed to generally evaluate effects of the thermal boundary condition on the heat transfer characteristics. A numerical solution of the adjoint problem enables us to predict the heat transfer characteristics, such as the total heat transfer rate or the temperature at a specific location, when the thermal boundary conditions change arbitrarily with time. Moreover, using the numerical solution of the adjoint problem, we can obtain the optimal thermal boundary conditions in both time and space to maximize the heat transfer at any arbitrary time. Numerical solutions of the adjoint problem in a lid‐driven cavity are presented to illustrate the capability of the present method. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(3): 237–247, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10032  相似文献   
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