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991.
From the energy saving viewpoint, the utilization of LNG cold is very important in the refrigeration industry concerning the low temperature region. In this paper, as a basic study of the freezing due to direct contact, including evaporation, solid–liquid direct contact heat transfer associated with sublimation has been investigated using the dry ice in water experimentally and theoretically. Based on a two-layers-model composed of CO2 vapor and the bulk water around the dry ice, the velocity and temperature fields in two layers was calculated numerically and the calculated results for the freezing condition of the bulk water were compared with the experimental results.  相似文献   
992.
Hypertrophic cardiomyopathy (HCM), the most common cause of sudden death in the young, is an autosomal dominant disease characterized by ventricular hypertrophy accompanied by myofibrillar disarrays. Linkage studies and candidate-gene approaches have demonstrated that about half of the patients have mutations in one of six disease genes: cardiac beta-myosin heavy chain (c beta MHC), cardiac troponin T (cTnT), alpha-tropomyosin (alpha TM), cardiac myosin binding protein C (cMBPC), ventricular myosin essential light chain (vMLC1) and ventricular myosin regulatory light chain (vMLC2) genes. Other disease genes remain unknown. Because all the known disease genes encode major contractile elements in cardiac muscle, we have systematically characterized the cardiac sarcomere genes, including cardiac troponin I (cTnI), cardiac actin (cACT) and cardiac troponin C (cTnC) in 184 unrelated patients with HCM and found mutations in the cTnI gene in several patients. Family studies showed that an Arg145Gly mutation was linked to HCM and a Lys206Gln mutation had occurred de novo, thus strongly suggesting that cTnI is the seventh HCM gene.  相似文献   
993.
On the mechanism of fatigue crack growth in silicon nitride   总被引:2,自引:0,他引:2  
The mechanism of fatigue crack growth in silicon nitride under the experimental conditions utilized is found to be of a cyclic nature, as contrasted to a form of static fatigue observed in some other ceramic systems. Conventional methods of analysis of the rate of fatigue crack growth in terms of ΔKeff are not applicable, because the results of the experimental portion of this investigation show that ΔKeff can decrease as the rate of fatigue crack growth increases. A mechanism which involves the formation of microcracks caused by a wedge effect which develops during the unloading portion of a cycle is discussed and evaluated. The wedge effect results from crack closure, which arises due to the roughness of the intergranular fracture surface as well as to debris trapped between the opposing fracture surfaces. In the proposed mechanism, the extent of crack advance per cycle is limited because of the decrease in stress intensity factor with crack advance in a given cycle associated with the wedge effect. The quantitative results of a semiempirical analysis of tests carried out in either air or vacuum are in agreement with some unusual experimental trends.  相似文献   
994.
A prototype of partial discharge (PD) pulse measurement and degradation diagnosis expert system (PDM/ES-I) is constructed using a personal computer for insulation degradation diagnosis of materials experiencing PDs. For 0.1-mm-thick low-density polyethylene (LDPE) with CIGRE Method II electrode system, temporal change of phase-angle-resolved PD pulse occurrence distribution was measured with PDM/ES-I. The so-called “pattern recognition” of the PD pulse distribution is applied to diagnosis of insulation degradation and assessment of residual life. Experimental results revealed that in spite of large scattering of time to breakdown, i.e., life, from 5 to 43 hours, all the tested samples exhibited similar evolution of the profile of PD pulse occurrence compared with five standard normalized PD patterns which had been registered in advance as five representative degradation stages from the initial degradation category to the final one. The degradation stage determined by the pattern recognition (PR) method proved to vary from the initial degradation category to the final one in a correct turn. Consequently, the PR method permitted an exact determination of the degree of degradation at a given aging time. In other words, the PR method was capable of predicting the residual life of LDPE with a CM-II electrode system.  相似文献   
995.
This paper deals with the effects of acetophenone coating on dielectric properties such as tan δ and capacitance and on space charge formation up to electrical breakdown under AC voltage application in low‐density polyethylene (LDPE) film. The existence of acetophenone at the electrical interface enhances tan δ. tan δ in acetophenone‐coated specimens increased with electric field and decreased with the frequency in the high‐field and high‐temperature region. AC breakdown test revealed that the electric strength in noncoated specimens was higher than in acetophenone‐coated specimens, and that the electric strength also decreased with temperature. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(3): 1–7, 2003; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.10086  相似文献   
996.
This paper reports the effects of a new p+ gate structure (MBN gate) on the properties of surface channel PMOSFET's with an extremely thin gate oxide. The MBN gate is a multilayer gate structure of boron-doped poly Si on thin nitrogen-doped poly-Si. The thin nitrogen-doped Si layer effectively suppresses boron diffusion, so that the gate poly Si can be doped with boron in high concentration without the fear of boron penetration. Gate depletion effects are well suppressed. Effective hole mobility is improved due to the reduction of the initial interface state density. The hot-hole induced interface state generation is shown to be the dominant clause of degradation in the 1/4-μm level PMOSFET's, and less Gm degradation is found in the MBN-gate PMOSFET's than in conventional p+-gate PMOSFET's. Finally, with respect to the reliability of the gate oxide, a conventional p+ gate with boron penetration exhibits an increase in short-time defect related breakdown during constant-current FN stressing. Short-time defect-related breakdown is not observed in the MBN gate but a slight decrease in charge to breakdown  相似文献   
997.
998.
Broad-band extreme ultraviolet (1340nm) lithography (EUVL) has been examined. Exposure intensity at the broad-band of 1340nm was 20 times larger than at the conventional narrow-band of 13nm. Moreover, broad-band EUVL with a wet-silylated and dry-developed resist process has been investigated in order to obtain a high resolution of 0.1μm with high-aspect-ratio. Imaging experiments were performed using 32:1 reduction Schwarzschild optics illuminated with a synchrotron radiation light source from SORTEC ring. The exposure was done through a 0.1μm-thick SiN vacuum window, Mo/Si multilayer coated optics and without a Be filter. Silylation characterization and determination of optimum composition of the silylation solution have been performed using Fourier transform infrared spectroscopy (FTIR). Using broad band EUVL with the optimal wet-silylated and dry-developed resist, 0.1μm lines and spaces of 0.55μm-thick resist (aspect RATIO = 5.5) can be successfully delineated.  相似文献   
999.
Corrosion diagnosis of carbon steel in fresh water was carried out by electrochemical method and Mahalanobis-Taguchi (MT) method. The corrosion morphology of carbon steel was classified by the combination of i-E curve measurement and chronopotentiometry. The MT method is one of discriminant analysis and can diagnose distinction data by multiple causes, i.e., ion concentrations. In the present paper, the concept for the application of this method to corrosion diagnosis is introduced. Additionally, electrochemical method was used for specific classification of carbon steel corrosion. By comparing the results of electrochemical measurements with those of Mahalanobis distance, the utility of MT method in the corrosion diagnosis was discussed.  相似文献   
1000.
Candida meningitis is a growing problem today. We report a 21-day-old male baby who was a victim of Candida albicans meningitis with the initial presentations of fever, mild stiff neck, poor feeding and activity. He had been treated with intravenous antibiotics and ventilator therapy prior to admission Initially, he was treated as a case of bacterial sepsis after admission with intravenous antibiotics. Due to positive cultures of cerebrospinal fluid for Candida albicans twice, intravenous amphotericin B was started from the 13th hospital day and was continued for 38 days. The successive three sets of CSF fungus culture yielded negative results and the patient was doing well without fever. Meanwhile, the brain sonogram revealed normal findings and he was discharged in a stable condition. We report this case and review some literature in an attempt to know more about this unusual disease, which is becoming more frequent as progress in intensive care grows.  相似文献   
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