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41.
Md Sazzadur Rahman MD Nahin Islam Shiblee Kumkum Ahmed Ajit Khosla Jun Ogawa Masaru Kawakami Hidemitsu Furukawa 《大分子材料与工程》2020,305(9)
In this work, 3D printable gel polymer electrolytes (GPEs) based on N,N‐dimethylacrylamide (DMAAm) and polyvinylidene fluoride (PVDF) in lithium chloride containing ethylene glycol solution are synthesized and their physicochemical properties are investigated. 3D printing is carried out with a customized stereolithography type 3D gel printer named “Soft and Wet Intelligent Matter‐Easy Realizer” and free forming GPE samples having variable shapes and sizes are obtained. Printed PVDF/PDMAAm‐based GPEs exhibit tunable mechanical properties and favorable thermal stability. Electrochemical proprieties of the printed GPEs are carried out via impedance spectroscopy in the temperature range of 25–90 °C by varying PVDF content. Ionic conductivity as high as 6.5 × 10?4 S cm?1 is achieved at room temperature for GPE containing low PVDF content (5 wt%) and conductivity of the GPEs is increased as temperature rises. 相似文献
42.
Abayomi P. Adebiyi Ayobamitale O. Adebiyi Tomohisa Ogawa & Koji Muramoto 《International Journal of Food Science & Technology》2008,43(1):35-43
Crude rice bran protein (CRBP) was prepared by alkaline extraction and then treated with 0.6 m HCl to remove phytic acid. The phytate‐free rice bran protein (PFRBP) was hydrolysed with proteases M, N, S, P and pepsin under optimal conditions. Hydrolysates obtained from various hydrolysis periods were subjected to analysis for their degree of hydrolysis (DH) and functional properties. The hydrolysates were fractionated by reversed‐phase column chromatography on Kaseigel ODS resin (120–140 μm) using a stepwise gradient of aqueous ethanol, and their activities were measured. The 40% ethanol fraction of protease P 4 h‐hydrolysate was separated by successive reversed‐phase high‐performance liquid chromatography and the amino acid sequences of isolated antioxidative peptides were determined by a protein sequencer and matrix‐assisted laser desorption ionisation‐time of flight mass spectrometry. Crude rice bran protein had higher antioxidative activity than PFRBP, due to the presence of phytic acid. Phytate contents of rice bran, CRBP and PFRBP were 2.5%, 1.42% and 0%, respectively. The activity of PFRBP increased upon protease digestion. Protease M hydrolysates showed the highest DH, but the lowest antioxidative activity. Hydrolysates with DH below 10% had higher antioxidative activity than those above 20%. This result indicates that the antioxidative activity of the hydrolysates is inherent to their characteristics amino acid sequences of peptides depending on the protease specificities. 相似文献
43.
Heat-moisture treatment of high-amylose corn starch increases dietary fiber content and lowers plasma cholesterol in ovariectomized rats 总被引:1,自引:0,他引:1
ABSTRACT: The effect of dietary high-amylose corn starch (HACS) of varying dietary fiber (DF) content on plasma cholesterol was examined in ovariectomized (OVX) rats. Gelatinized normal corn starch (G-CS) was used as a reference. OVX rats were fed a fiber-free purified diet containing G-CS, HACS, gelatinized high-amylose corn starch (G-HACS), or heat-moisture treated HACS (HM-HACS) at 400 g starch/kg diet for 21 d. The DF content of G-CS, HACS, G-HACS, and HM-HACS measured by the AOAC method was 0.1, 19.3, 2.4, and 64.5 g/100 g, respectively. The dry weight of cecal contents, cecal wall weight, the amount of short chain fatty acids in cecal contents, the amount of bile acids in small intestinal contents, and fecal excretion of neutral sterols increased logarithmically with increasing DF, while total plasma cholesterol concentration decreased. On the other hand, hepatic CYP7A1 activity, fecal dry weight, and fecal excretion of bile acids increased linearly with increasing DF, while body weight gain decreased. The hypocholesterolemic effect of HACS in OVX-rats appeared to be more effective by heat-moisture treatment. 相似文献
44.
Regiospecific analysis by ethanolysis of oil with immobilized <Emphasis Type="Italic">Candida antarctica</Emphasis> lipase 总被引:1,自引:1,他引:1
Shimada Y Ogawa J Watanabe Y Nagao T Kawashima A Kobayashi T Shimizu S 《Lipids》2003,38(12):1281-1286
A mixture of oil/ethanol (1∶3, w/w) was shaken at 30°C with 4% immobilized Candida antarctica lipase by weight of the reaction mixture. The reaction regiospecifically converted FA at the 1- and 3-positions to FA ethyl
esters, and the lipase acted on C14−C24 FA to a similar degree. The content of 2-MAG reached a maximum after 4 h; the content was 28–29 mol% based on the total amount
of FA in the reaction mixture at 59–69% ethanolysis. Only 2-MAG were present in the reaction mixture during the first 4 h,
and 1(3)-MAG were detected after 7 h. After removal of ethanol from the 4-h reaction mixture by evaporation, 2-MAG were fractionated
by silica gel column chromatography. The contents of FA in the 2-MAG obtained by ethanolysis of several oils coincided well
with FA compositions at the 2-position, which was analyzed by Grignard degradation. It was shown that ethanolysis of oil with
C. antarctica lipase can be applied to analysis of FA composition at the 2-position in TAG. 相似文献
45.
Explosion sensitivity involves many complex factors. A theory for evaluating and a method for testing have to be established. We have proposed an explosion sensitivity theory for explosive substances and have also tested the evaluating method. The results of our research reveal a satisfactory mutual relation between both theoretical and experimental values. 相似文献
46.
Yasutaka Miyachi Takashi Miyazawa Yoshihiro Ogawa 《International journal of molecular sciences》2022,23(6)
Understanding the genetic factors of diabetes is essential for addressing the global increase in type 2 diabetes. HNF1A mutations cause a monogenic form of diabetes called maturity-onset diabetes of the young (MODY), and HNF1A single-nucleotide polymorphisms are associated with the development of type 2 diabetes. Numerous studies have been conducted, mainly using genetically modified mice, to explore the molecular basis for the development of diabetes caused by HNF1A mutations, and to reveal the roles of HNF1A in multiple organs, including insulin secretion from pancreatic beta cells, lipid metabolism and protein synthesis in the liver, and urinary glucose reabsorption in the kidneys. Recent studies using human stem cells that mimic MODY have provided new insights into beta cell dysfunction. In this article, we discuss the involvement of HNF1A in beta cell dysfunction by reviewing previous studies using genetically modified mice and recent findings in human stem cell-derived beta cells. 相似文献
47.
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49.
For the design of radio local distribution systems in densely built-up areas, estimating how many subscribers are in sight from a nodal station is important. This paper proposes a method for estimating probability of success of line-of-sight paths termed visibility. Method validity is confirmed bypractical field examinations. 相似文献
50.
Hori H. Kitayama Y. Kitano M. Yabuzaki T. Ogawa T. 《Quantum Electronics, IEEE Journal of》1983,19(2):169-175
Experimental results are shown on the frequency stabilization of a GaAlAs laser using a Doppler-free spectrum in the saturated absorption of the Cs-D2 line at 852.1 nm. The frequency stability (Allan variance) between3.0 times 10^{-12} and1.0 times 10^{11} was obtained at the averaging time between 0.1 and 1000 s. 相似文献