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1.
a-Si alloy three-stacked solar cells have been studied to improve the stabilized efficiency of a-Si: H based solar cells. Based on the analysis by the individual characterization method of the component cells in stacked type cells, the a-Si :H middle cell was replaced with an a-SiGe :H cell. Furthermore, the optical confinement technology was improved to obtain a high-output current with thin i-layer thickness in the a-SiGe :H bottom cell. By this device design, the initial conversion efficiency was improved up to 12.4% and more than a 10% stabilized efficiency was obtained in a-SiC :H/a-SiGe :H/a-SiGe :H three-stacked cells. These cell characteristics were confirmed by measurements at the JQA Organization (the former JMI Institute).  相似文献   
2.
A low-loss and wide-bandwidth optical fibre in the long-wavelength region has been fabricated by the v.a.d. method. Loss at 1.3 ?m is 0.98 dB/km and 6 dB down bandwidth is 1600 MHz km at 1.26 ?m.  相似文献   
3.
A large preform for 220 km of fibre was fabricated with the vapour-phase axial deposition (VAD) method. The deposition rate for the core was 1.7 g/min. Optical fibre drawn from a part of the preform had optical attenuation of 0.58 dB/km and bandwidth 500 MHz km0.9 at a wavelength of 1.3 ?m.  相似文献   
4.
It was found that there was a close relationship between chill formation and nodule count in spheroidal-graphite (s-g) cast irons and, further, that there was a critical nodule count above which chill did not appear. The relationship between the critical nodule count and the cooling rate of specimens was expressed in the following quadratic equation:

N=0.58R2+19.07R+1.01

where N is the critical nodule count (mm?2) and R is the cooling rate (°C/sec). Nodule count was increased by adding small amounts of a rare earth in combination with small amounts of calcium. Some heterogeneous phases with diameters of 1 μ or more were observed at the centres of graphite spheroids. These phases were composed of spherical rare-earth sulphides containing MgS, CaS and MgO. It is suggested that rare-earth sulphides contribute as a substrate on which graphite spheroids are formed in thin section cast irons, containing rare earth elements.  相似文献   
5.
In this study, the entrance surface dose rates received by a phantom during cineangiography and fluoroscopy were compared. The X-ray conditions used in the measurements were those normally used in facilities performing percutaneous coronary intervention. Although, today, the entrance surface doses (cineangiography and fluoroscopy) of X-ray equipment used for cardiac interventional radiology (IVR) tends to be lower than they were previously, some equipment produces a high radiation dose. Therefore, the X-ray equipment used for cardiac IVR procedures must be maintained in good repair and must be carefully calibrated. In addition, periodic measurement of the radiation dose from the X-ray equipment used for both cineangiography and fluoroscopy for cardiac IVR is necessary. If the radiation dose of the X-ray system in use is too high, the IVR staff should determine the reason and make an effort to reduce it. Hence, the IVR staff must be adequately trained in radiation protection.  相似文献   
6.
7.
As the atmospheric electric field always fluctuates, its observed waveforms are very complicated. It is important to detect the characteristic variation from the observed signals and determine its cause. The natural observation method is adequate for analyzing such nonperiodic signals as the atmospheric electric field signals. In this method the aspectum is proposed as the quantity to estimate the instantaneous power. In this study signal processing by the aspectum was applied to signals of atmospheric electric field variation. It was clarified that a strong correlation exists between the instantaneous fluctuations of atmospheric electric field and the wind speed in the convenient meteorological environment. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 27–34, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20302  相似文献   
8.
We report two cases of idiopathic interstitial pneumonia (IIP) with acute deterioration after bronchoalveolar lavage (BAL). Case 1 was a 54-year-old woman, and case 2 was a 75-year-old man. Both were diagnosed as having IIP, and hospitalized with complaints of high fever and dyspnea. After BAL, the degree of dyspnea increased. White blood cell count and lactate dehydrogenase were elevated, and PaO2 was decreased. Chest X-ray revealed consolidation of the upper lung fields and reticulo-granular shadows spreading through both lungs. BAL fluid examination showed an elevated neutrophil fraction (case 1: 6.5%, case 2: 35.2%), suggesting respiratory tract infection although bacteria could not be detected. Case 1 died of respiratory failure despite corticosteroid therapy. Autopsy revealed diffuse alveolar damage with focal pneumonia in the right S6 corresponding to the upper lobe consolidation. Case 2 improved after antibiotic therapy. These findings suggest that aspiration of infected fluid during BAL can cause acute exacerbation of IIP. It is important to recognize that the BAL procedure can induce an acute exacerbation of IIP.  相似文献   
9.
A hydrogen generation process using photocatalytic reactions has been proposed. In this process, hydrogen sulfide is a source of hydrogen and is turned into polysulfide. In order to establish the cyclic operation of a photocatalytic hydrogen generation system, it is necessary to convert polysulfide back into hydrogen sulfide with a small energy input. This paper proposes the use of sulfate-reducing bacteria (SRB) for the regeneration of hydrogen sulfide. Batch cultivation of natural source SRB samples were carried out using a culture medium containing polysulfide as the only sulfur compound source. SRB produced hydrogen sulfide from several kinds of polysulfide sources, including a photocatalytic hydrogen generation-produces solution. Production lag phase and production rate of hydrogen sulfide were affected by initial polysulfide concentration. SRB activity was inhibited at high initial polysulfide concentrations. SRB enrichment culture T2, exhibited the highest hydrogen sulfide production rate, and was able to utilize several kinds of organic matter as the electron donor. The results suggest the possibility of using large biomass sources, such as sewage sludge and the raw garbage in a hydrogen generation system. We developed speculative estimates that an SRB based hydrogen generation system is feasible.  相似文献   
10.
[Correction Notice: An erratum for this article was reported in Vol 135(5) of Psychological Bulletin (see record 2009-12487-006). There is an error in Table 1. On p. 840 the entry for Hill et al. 1987 should be Masters et al. 2004.] This meta-analysis included 729 studies from 161 articles investigating how acute stress responsivity (including stress reactivity and recovery of hypothalamic-pituitary-adrenal [HPA] axis, autonomic, and cardiovascular systems) changes with various chronic psychosocial exposures (job stress; general life stress; depression or hopelessness; anxiety, neuroticism, or negative affect; hostility, aggression, or Type-A behavior; fatigue, burnout, or exhaustion; positive psychological states or traits) in healthy populations. In either the overall meta-analysis or the methodologically strong subanalysis, positive psychological states or traits were associated with reduced HPA reactivity. Hostility, aggression, or Type-A behavior was associated with increased cardiovascular (heart rate or blood pressure) reactivity, whereas anxiety, neuroticism, or negative affect was associated with decreased cardiovascular reactivity. General life stress and anxiety, neuroticism, or negative affect were associated with poorer cardiovascular recovery. However, regarding the sympathetic nervous system and parasympathetic nervous system, there were no associations between the chronic psychosocial factors and stress reactivity or recovery. The results largely reflect an integrated stress response pattern of hypo- or hyperactivity depending on the specific nature of the psychosocial background. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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