Thermoelectric Generation Using Water Lenses

A solar light concentrator composed of water and plastic transparent film has been designed. This flexible lens design can trace the solar movement through control of the tensile stress and amount of water, and concentrate the solar energy onto the thermoelectric (TE) module surface. An experimental water lens was constructed, and the concentrated intensity was monitored by a photodiode as a function of x–z position; For example, when 3.0 kg water was filled and tension of 69.0 N/m was applied to the transparent vinyl sheet, the concentration ratio was evaluated as the maximum of 28.0 at a depth of 657 mm from the water lens bottom surface. TE generation was tested to show the validity of the water lens. The surface condition of the receiver was found to be critical.     

Photoluminescence Analysis of Iron Contamination Effect in Multicrystalline Silicon Wafers for Solar Cells

We investigated the effect of Fe contamination on the electronic properties of dislocation clusters in relation to oxygen precipitation in multicrystalline silicon (mc-Si). Photoluminescence (PL) spectroscopy and mapping were performed at room and liquid-He temperatures on mc-Si wafers before and after Fe contamination. PL spectra consisted of the band-edge emission, the 0.78-eV emission associated with oxygen precipitates, and the dislocation-related D-lines. The Fe contamination increased the electrically active dislocation clusters. Part of these clusters acted as preferential oxygen precipitation sites, and their electronic properties were not further influenced by the Fe contamination.     

Evaluation of Stress and Crystal Quality in Si During Shallow Trench Isolation by UV-Raman Spectroscopy

Defects and stress gradually accumulate throughout various Si large-scale integration fabrication processes. It is essential to monitor defects and stress carefully to suppress their unintentional introduction. In this study, we measured the stress and crystal quality in shallow trench isolation (STI) samples by ultraviolet (UV)-Raman spectroscopy with an extremely high-resolution wavenumber to evaluate the effect of post-annealing on the recovery of Si crystals. The variations of crystal quality in 200-mm wafers with STI structures gradually decreased after post-annealing for 4 h, 6 h, and 8 h; however, there was no substantial difference in the values of full-width at half-maximum of the Raman spectra. Precise measurements of variations of stress and crystal quality were successfully performed by UV-Raman spectroscopy with a high-resolution wavenumber, which enabled us to evaluate the STI process accurately.     

An AlGaAs/GaAs short-cavity laser and its monolithic integration using microcleaved facets (MCF) process

This paper describes the microcleaved facets (MCF) process developed for AlGaAs/GaAs laser fabrication which can avoid the previous substrate cleavage and therefore be applicable to preparing both discrete short-cavity lasers and optoelectronic integrated circuits (OEIC's). An AlGaAs/GaAs double heterostructure ridge-waveguide laser with an extremely short cavity length, namely 20 μm, was first realized by this process. A threshold current as low as 20 mA and a single longitudinal mode lasing were achieved. The usefulness of this process for integrating a laser and a monitoring photodiode on a GaAs substrate is also demonstrated.     

High-cycle fatigue characteristics of quasi-isotropic CFRP laminates over 10 cycles (Initiation and propagation of delamination considering interaction with transverse cracks)

High-cycle fatigue features of over 10⁸ cycles, particularly the initiation and propagation of edge delamination considering the effects of transverse cracks, were investigated using quasi-isotropic carbon-fiber-reinforced plastic (CFRP) laminates with a stacking sequence of [45/0/−45/90]_s in this study. In the relationship between a transverse crack density and initiation and growth of edge delamination, it was found that fatigue damage growth behavior varied depending on applied stress. It was observed that edge delamination initiated and grew at parts where transverse cracks were dense at ordinary applied stress, whereas it was observed that edge delamination grew before or simultaneously with transverse crack propagation at a low applied stress and high-cycle loading. In addition, the critical transverse crack density where delamination begins growing was calculated to evaluate the interaction between transverse crack and edge delamination growth.     

Chemical analysis and acetylcholinesterase inhibitory effect of anthocyanin-rich red leaf tea (cv. Sunrouge)

BACKGROUND: The purpose of this study was to evaluate the effects of leaf order or crop season on anthocyanins and other chemicals in the anthocyanin‐rich tea cultivar ‘Sunrouge’ (Camellia sinensis x C. taliensis) by using high‐performance liquid chromatography, and to study the effect of ‘Sunrouge’ extract on acetylcholinesterase (AChE) activity in human neuroblastoma SK‐N‐SH cells. RESULTS: The total anthocyanin content was higher in the third (3.09 mg g^?1) than in the second (2.24 mg g^?1) or first crop season (1.79 mg g^?1). The amount of anthocyanins contained in the stem was high (1.61 mg g^?1). In the third crop season, the concentrations of delphinidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside (DCGa), cyanidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside, delphinidin‐3‐O‐β‐D ‐galactopyranoside, delphinidin‐3‐O‐β‐D ‐(6‐O‐(Z)‐p‐coumaroyl)galactopyranoside, cyanidin‐3‐O‐β‐D ‐galactoside, and delphinidin‐3‐O‐β‐D ‐glucoside were 1.57 mg g^?1, 0.52 mg g^?1, 0.40 mg g^?1, 0.22 mg g^?1, 0.14 mg g^?1, and 0.11 mg g^?1, respectively. DCGa accounted for about 50% of the anthocyanins present. The suppressive effect of ‘Sunrouge’ water extract on AChE activity in human neuroblastoma SK‐N‐SH cells was the strongest among the three tea cultivars (‘Sunrouge’, ‘Yabukita’ and ‘Benifuuki’). CONCLUSION: These results suggested that ‘Sunrouge’ might protect humans from humans from AChE‐related diseases by suppressing AChE activity. To obtain sufficient amounts of anthocyanins, catechins and/or caffeine for a functional food material, ‘Sunrouge’ from the third crop season should be used. Copyright © 2012 Society of Chemical Industry     

Quantitative risk assessment of noroviruses in drinking water based on qualitative data in Japan

Noroviruses are one of the major causes of viral gastroenteritis in Japan. A quantitative risk assessment was conducted to evaluate the health risk caused by this virus in drinking water. A Monte Carlo analysis was used to calculate both the probability of infection and the disease burden using disability-adjusted life years (DALYs). The concentration of noroviruses in tap water was estimated based on qualitative data and a most probable number (MPN) method with an assumed Poisson lognormal distribution. This numerical method was evaluated using two sets of available count data of Cryptosporidium: that collected from a river and that found in tap water in Japan. The dose-response relationships for noroviruses were estimated using assumed ID50 (10 or 100). The annual risk was higher than the US-EPA acceptable level (10(-4) [infection/ person-year]) but around the WHO level (10(-6) [DALYs/ person-year]). As suggested by others, since microbial concentrations are generally lognormally distributed, the arithmetic mean was directly related to the annual risk, suggesting that the arithmetic mean is more useful in representing the degree of microbial contamination than the geometric mean.     

Fibrinogen/fibrin degradation products in serum of patients with idiopathic thrombocytopenic purpura: elevated levels during severe thrombocytopenic phase of the disease

Sera from 23 patients with idiopathic thrombocytopenic purpura (ITP), 14 patients with aplastic anemia with severe thrombocytopenia and healthy control subjects were tested for the presence of fibrinogen/fibrin degradation products (FDP), using the tanned red cell hemagglutination inhibition immunoaassay. The concentrations of circulating FDP of ITP patients (mean 12.01 mug/ml) were significantly higher than those of the patients with aplastic anemia (mean 4.01 mug/ml, p less than 0.05) or normal controls (mean 3.10 mug/ml, p less than 0.001). The patients with untreated ITP with very low platelet counts had higher levels of FDP than those of the treated group (p less than 0.01). Serum FDP and a battery of other coagulation-fibrinolysis tests were serially carried out over a period of 10 weeks in two patients with ITP. The initially high FDP promptly decreased as circulating platelets increased in response to steroid in both patients, while plasma fibrinogen, euglobulin lysis time, prothrombin time and partial thromboplastin time remained essentially normal during the course of observation. The exact source of the increased serum FDP in ITP was not established, but a few possible mechanisms responsible for this abnormality were discussed.