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1.
There is a moderate inversion region between the weak and strong inversion regions of MOSFET operation. This region is very important for designing analog circuits. This paper presents a new explicit expression for the surface potential at the high-end of the moderate inversion, which is useful for a circuit modeling. This expression allows a new definition for the threshold voltage Vth and a model of the relation between off-current Ioff and on-current Ion of MOSFETs. A source resistance Rs has large influence on Ion, so that a model for Rs was newly developed. Proposed models for Vth and Ioff-Ion characteristics were compared with experiments. It is found that the new definition Of Vth could apply to both short- and long-channel MOSFETs. The model revealed different Ioff-Ion behaviors between high and low halo dose MOSFETs  相似文献   
2.
The cell-free extracts of 60 strains which were identified phenotypically as being those of Lactobacillus brevis, including 48 isolates from the environment and 12 reference strains, were applied to polyacrylamide gel electrophoresis for extracting their NAD-dependent D- and L-lactate dehydrogenases (LDH). These strains were divided into 5 groups, i.e., Groups A, B, C, D, and E, on the basis of the electrophoretic mobilities of their D-LDH. The strains showed variations in their carbohydrate fermentation patterns. No relationship between the profile of D-LDH and the carbohydrate fermentation pattern was recognized. However, there appeared to be a relationship between the D-LDH profile and the beer-spoilage ability, because 40 out of 44 beer-spoilage strains identified as L. brevis were classified to Group B. We purified D-LDHs from the so-called complete beer-spoilage strain SBC 8002 of LDH Group B and from the non beer-spoilage strains JCM 1059T of LDH Group A and AHU 1508 of LDH Group C. Although the purified D-LDHs had the same molecular weight (84 kDa), each possessed a different optimum pH, optimum temperature, and isoelectric point. The aforementioned parameter values for the enzyme from the so-called complete beer-spoilage strain SBC 8002 of LDH Group B were 10.0, 50 degrees C, and 4.1, respectively; this strain was discriminated from the D-LDHs of the other two non beer-spoilage strains especially by its optimum temperature (50 degrees C).  相似文献   
3.
In an asynchronous pulsewidth modulation (PWM) method, the ratio of the carrier frequency to the fundamental frequency must be at least 15-20 in order to suppress the beat phenomenon. However, it is impossible to achieve this condition for large-capacity inverters (e.g., gate-turn-off thyristor inverters), when the fundamental frequency is high. Assuming that the beat phenomenon is caused by an error generated in the PWM process, the authors have introduced a compensator to reduce the error. As a result, beat phenomenon can be decreased for a low carrier frequency. Effectiveness of the proposed method is shown by experimental results  相似文献   
4.
A previously developed fluorometric assay using synthetic substrate, Succinyl-Arg-Pro-Phe-His-Leu-Leu-Val-Tyr-4-methylcoumaryl-7-amide, for yeast proteinase A (PrA) was modified for the accurate and quick determination for the activity in unpasteurized beer. Employing simple HPLC for the determination of 7-amino-4-methylcoumarine (AMC), a final degradation product on this assay, the activity of PrA in beer was measured without the interference of the fluorogenic and photosensitive substance present in beer. The assay for common unpasteurized beers was completed within 5 hours without any concentration procedure. Its linearity and reproducibility were satisfactory for quantitative purposes. Using a purified PrA from brewer's yeast, the effect of the PrA activity on foam stability during storage was furthermore clarified. The exclusive effect of PrA on foam stability was also demonstrated by proteinase inhibitor test.  相似文献   
5.
In situ imaging of molecular markers on a physical chromosome is an indispensable tool for refining genetic maps and validation genome assembly at the chromosomal level. Despite the tremendous progress in genome sequencing, the plant genome assembly at the chromosome level remains a challenge. Recently developed optical and Hi-C mapping are aimed at assistance in genome assembly. For high confidence in the genome assembly at chromosome level, more independent approaches are required. The present study is aimed at refining an ultrasensitive Tyr-FISH technique and developing a reliable and simple method of in situ mapping of a short unique DNA sequences on plant chromosomes. We have carefully analyzed the critical steps of the Tyr-FISH to find out the reasons behind the flaws of this technique. The accurate visualization of markers/genes appeared to be significantly dependent on the means of chromosome slide preparation, probe design and labeling, and high stringency washing. Appropriate adjustment of these steps allowed us to detect a short DNA sequence of 1.6 Kb with a frequency of 51.6%. Based on our results, we developed a more reliable and simple protocol for dual-color Tyr-FISH visualization of unique short DNA sequences on plant chromosomes. This new protocol can allow for more accurate determination of the physical distance between markers and can be applied for faster integration of genetic and cytogenetic maps.  相似文献   
6.
The engineering validation of the IFMIF/EVEDA prototype accelerator, up to 9 MeV by supplying the deuteron beam of 125 mA, will be performed at the BA site in Rokkasho. A design of this area monitoring system, comprising of Si semiconductors and ionization chambers for covering wide energy spectrum of gamma-rays and 3He counters for neutrons, is now in progress. To establish an applicability of this monitoring system, photon and neutron energies have to be suppressed to the detector ranges of 1.5 MeV and 15 MeV, respectively. For this purpose, the reduction of neutron and photon energies throughout shield of water in a beam dump and concrete layer is evaluated by PHITS code, using the experimental data of neutron source spectra. In this article, a similar model using the beam dump structure and the position with a degree of leaning for concrete wall in the accelerator vault is used, and their energy reduction including the air is evaluated. It is found that the neutron and photon flux are decreased by 104-order by employing the local shields using concrete and polyethylene around beam dump, and the photon energy can be suppressed in the low energy.  相似文献   
7.
Based on a three-dimensional numerical analysis, it is shown that narrow-width MOSFETs of the BOX structure1 exhibit an `inverse? narrow-channel effect whereby their threshold voltages become lower and lower with decreasing channel width. The phenomenon is attributed to a pronounced enhancement of the channel edge region due to a crowding of the fringing field.  相似文献   
8.
BACKGROUND: A high incidence of backache with radiating pains to the lower extremities, termed transient radicular irritation (TRI), has been reported following the use of 5% hyperbaric lidocaine. This has been attributed to a neurotoxic reaction. METHODS: A retrospective audit has been carried out in our hospital on the postoperative anaesthetic records of all patients from the 1st of January 1993 to the 1st of September 1996, who received spinal anaesthesia with either hyperbaric lidocaine or hyperbaric bupivacaine for day-care surgery. RESULTS: Backache was reported in 1.9% of patients (6/322) receiving hyperbaric lidocaine and in 2.4% of patients (1/41) receiving hyperbaric bupivacaine. This was not associated with any sensory, motor or sphincter disturbances. One patient complained of backache with bilateral pain referred to the gluteal area (TRI), which was assessed as acute facet joint syndrome. Unilateral accidental block of the femoral nerve was observed in 3 patients, sensory disturbances in the L2/3 dermatome was reported in a further 3 patients at 24 h, following wound infiltration with local anaesthetic during hernia repair. CONCLUSIONS: The low incidence of backache at 24 h and the absence of associated symptoms of neurogenic pain, sensory and motor disturbances, does not support the hypothesis that TRI is a neurotoxic reaction, subsequent to the use of hyperbaric lidocaine.  相似文献   
9.
10.
This paper describes a design of the electrostatic discharge (ESD) protection device to minimize its area Ap while maintaining the breakdown voltage VESD. Hypothesis tests using measured data were performed to find the severest applied serge condition and to select control factors for the design-of-experiments (DOE). Also, technology CAD (TCAD) was used to estimate VESD. An optimum device structure, where salicide block was employed, was found using statistical methods and TCAD.  相似文献   
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