Characterization of Li<Subscript>2</Subscript>S–P<Subscript>2</Subscript>S<Subscript>5</Subscript>–Cu composite electrode for all-solid-state lithium secondary batteries

Electrochemical performance of the Li₂S–P₂S₅–Cu composite materials was examined in all-solid-state lithium secondary batteries. The 80Li₂S·20P₂S₅ (mol.%) solid electrolyte with the addition of Cu was partially used as an active material with lithium source in all-solid-state cells. The initial discharge capacity of 110 mAh g⁻¹ (normalized by the weight of 80Li₂S·20P₂S₅–Cu), which corresponds to 400 mAh g⁻¹ (normalized by the weight of Li₂S), was obtained in the cell using the 80Li₂S·20P₂S₅–Cu composite electrode with the molar ratio of Li₂S/Cu = 48/52. Cycling performance and reaction mechanism of the electrode in the solid-state cell were investigated.     

Thermal fatigue of Ag flake sintering die-attachment for Si/SiC power devices

Emerging SiC power semiconductor devices are expected to work under the high temperature condition of 250–300 °C while the operation of Si devices is limited up to 180 °C. The die-bonding materials for emerging SiC power devices hence need to have sufficient capability in such extreme operating environments. In this study, we investigated the thermomechanical reliability of the die-attach technology using Ag flake paste, which can be processed by low-temperature and low-pressure sintering. The Ag flakes start to sinter immediately after the organic dispersant layer is removed from the flake surface at 160 °C, and die-bonding consequently becomes possible. The tested Si die-attachments joining with the paste maintained high strength (23 MPa) up to 1,000 thermal cycles from ?40 to 180 °C. The stable microstructures without crack and no interfacial debonding assure the reliability of the Ag flake paste die-attach of Si. SiC die-attachments also maintained their high strength (24 MPa) up to 1,000 cycles of ?40 and 250 °C, though a slight degradation appeared after 1,000 cycles. The debondings at the sintered Ag flake paste layer/SiC wafer interface were affected to the joining strength with the Ag flake paste. The obtained results indicate that our Ag flake paste die-attach can be applied to both Si and SiC power devices capable of high temperature operations.     

Effects of oil heated with gluten on weight-loss dieting. II

We previously proposed that oil heated with gluten was suitable for use as a safe oil for weight-loss dieting. In the present paper, the properties of the oil were improved, and the weight-loss effect was compared with that of heated oil. Fresh oil was heated for 10 h at 180 degrees C with or without gluten and filtered using filter paper. A powdered diet (AIN93G; no fat) was mixed with 7 wt% of fresh oil (control) or filtrates of the heated oils described above, and the mixture was fed to male Wistar rats for 12 weeks. The gluten and heated oil groups showed no gross symptoms attributable to the experimental oils but had a slowed body weight increase; a significant difference was found in weight on and after 21 weeks of age as compared to rats consuming the control diet, and fecal excretion was increased as compared to the control group. Serum levels of triacylglycerol, phospholipids, cholesterol, and glucose of the gluten and heated oil groups were significantly lower than those of the control group. High aspartate aminotransferase (AST) levels occurred more frequently in the heated oil group than the gluten group. The number of rats with dark red patches on the surface of the liver, which are indicative of liver damage, was higher in the heated oil group. In conclusion, the weight-reducing effect of the oil heated with gluten was confirmed and improved by removing traces of heated gluten from the oil.     

Mechanisms Underlying Decreased Hepatic Triacylglycerol and Cholesterol by Dietary Bitter Melon Extract in the Rat

In these studies, we focused on finding the mechanism(s) underlying the bitter melon (Momordica charantia L.) methanol fraction (MF)-dependent reduction in the concentration of hepatic triacylglycerol (TAG) and cholesterol in the rat. Rats were fed diets containing low (5 %) fat for 2 weeks (experiment 1), or low (5 %) and high (15 %) fat for a longer period of 8 weeks (experiment 2). MF was supplemented at 1 % level in both experiments. After feeding, rats were sacrificed, and their livers were prepared as slices and hepatocytes, followed by incubation with [1(2)-¹⁴C] acetate or [1-¹⁴C] oleic acid (18:1 n-6). Under these conditions, we found that rats fed diets containing MF, as compared to those without MF, showed: (1) no adverse effects on food intake and growth, (2) a decreased hepatic TAG and total cholesterol, irrespective of the difference in dietary fat level or feeding period, and (3) a decreased incorporation of [1(2)-¹⁴C] acetate and [1-¹⁴C] oleic acid into TAG of liver slices and hepatocytes. MF-supplemented rats also showed no altered incorporation of labeled acetate into cholesterol and cholesterol ester, an increased fecal excretion of neutral steroids, but not of acidic steroids, and an enhanced mRNA abundance of carnitine palmitoylacyltransferase I, which is the rate-limiting enzyme for fatty acid oxidation. These results suggest that dietary MF decreases hepatic TAG synthesis while enhancing fatty acid oxidation, thereby reducing the concentration of hepatic TAG. The liver cholesterol-lowering effect of MF, however, is probably mediated through an increased fecal excretion of neutral steroids, without an effect on cholesterogenesis.     

Intestinal absorption of dietary carotenoids

The assessment of carotenoid bioavailability has long been hampered by the limited knowledge of their absorption mechanisms. However, recent reports have elucidated important aspects of carotenoid digestion and absorption. Disruption of food matrix and increasing amounts of fat seem to enhance the absorption of carotenes to a larger extent than that of xanthophylls. Comparing different carotenoid species, xanthophylls seem to be more easily released from the food matrix and more efficiently micellized than the carotenes. On the other hand, carotenes are more efficiently taken up by the enterocytes. However, carotenoid emulsification and micellization steps are largely affected by the food matrix and dietary components, being the main determinant of carotenoid bioavailability from foodstuffs. Although the intestinal uptake of carotenoids has been thought to occur by simple diffusion, recent studies reported the existence of receptor-mediated transport of carotenoids in enterocytes. Comparisons between the intestinal absorption of a wide array of carotenoids would be useful to elucidate the absorption mechanism of each carotenoid species, in view of the recent indications that intestinal carotenoid uptake may involve the scavenger receptor class B type I and possibly other epithelial transporters. The unraveling of the whole mechanism underlying the absorption of carotenoids will be the challenge for future studies.     

Stabilization of Microcapsules Using a Freeze-Dried Gelatin Matrix: Aqueous Redispersibility and the Ingredient Activity

Microcapsules are of great interest to the food and pharmaceutical industries as vehicles to deliver active ingredients to the gastrointestinal tract. Drying plays an important role in stabilizing microcapsules to prolong their lifetime; however, drying often produces undesirable changes in the microcapsules, such as irreversible aggregation of the microcapsules and activity loss of the encapsulated ingredient. In this work, poly(epsilon-caprolactone) microcapsules containing a model bioactive compound (tocopherol) were prepared and stabilized in a freeze-dried gelatin matrix. This dried product was rehydrated and the aqueous redispersibility of the microcapsules and the tocopherol activity were investigated. The experimental results suggested that a kinetic balance between dehydration (caused by freezing) and gel network formation is a critical factor that affects the redispersibility and ingredient activity of the products. It was further suggested that a hydrogel-based product could be strategically freeze dried to maximize product quality by tuning its freezing process; that is, by employing a controllable dehydration process.     

All solid-state battery with sulfur electrode and thio-LISICON electrolyte

A high-capacity type of all solid-state battery was developed using sulfur electrode and the thio-LISICON electrolyte. New nano-composite of sulfur and acetylene black (AB) with an average particle size of 1–10 nm was fabricated by gas-phase mixing and showed a reversible capacity of 900 mAh g⁻¹ at a current density of 0.013 mA cm⁻².     

All solid-state sheet battery using lithium inorganic solid electrolyte, thio-LISICON

All solid-state sheet lithium battery was developed using inorganic solid electrolyte, thio-LISICON (Li_3.25Ge_0.25P_0.75S₄), Li–Al anode, and Mo₆S₈ cathode materials, and the sheet manufacturing process was established. The new sheet-configuration was consisted of the cathode with the grid of current collector, electrolyte sheet with or without mechanical support, and aluminum/lithium composite sheet anode. A sheet battery with a dimension of 30 mm × 30 mm showed good charge–discharge characteristics without any capacity fading at a current of 0.1 mA.