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91.
Changes in eicosanoid production may contribute to some of the complications of the aging process such as atherosclerosis
and glomerular sclerosis. Polyunsaturated fatty acids of the n-6 and n-3 series are precursors of eicosanoids. We fed diets
containing safflower oil as a source of n-6 fatty acids, fish oil as a source of n-3 fatty acids or beef tallow as a source
of saturated fats to three groups of normal rats from 2–18 months of age. We demonstrated incorporation of the n-3 fatty acids,
20:5n-3 and 22:6n-3 into kidney phospholipids. Feeding of the diet containing n-3 fatty acids was associated with a markedly
decreased giomerular production of PGE, 6-keto-PGF1α and TXB2. It also decreased the aortic production of 6-keto-PGF1α and platelet production of TXB2. No significant effect of n-6 fatty acids on dienoic eicosanoid production was observed. There were no adverse effects on
kidney function as measured by urinary protein excretion and serum creatinine levels or on renal morphology by any diet. A
diet enriched in n-3 fatty acids for 18 months remains effective in decreasing dienoic eicosanoids in the aging rat. 相似文献
92.
Application of an enteric coat increases the resistance to gastric juices for swallowable biosensors
Yuji Murakami Yi Zhang Tsuyoshi Takeuchi Tomohide Noda Kenichi Noda Akio KurodaAuthor vitae 《Sensors and actuators. B, Chemical》2011,160(1):379
This paper describes a biosensor with an immobilized-electron mediator that was covered with an enteric coat to generate a swallowable biosensor. Ferrocene-attached poly-l-lysine was crosslinked with glucose oxidase and bovine serum albumin by glutaraldehyde on a Au- or Pt-disc electrode, or a screen-printed electrode. The electrode was dip-coated to generate the enteric coat. The glucose sensor with enteric coat retained its activity under anaerobic conditions after 3 h of artificial gastric juice treatment. Mixing the enteric coat solution with plasticizer resulted in an enhanced stability of the coat. The proposed method is useful to construct the swallowable biosensor for non-invasive continuous glucose monitoring. 相似文献
93.
We have developed novel excitation circuits without high-voltage switches for two longitudinally excited N(2) lasers (wavelength: 337 nm). One uses a single tube without a trigger and the other uses a tandem tube with a trigger. In both systems, the discharge tube acts as a switch. In the single-tube system, the laser output energy was 125.8 microJ and the efficiency was 0.16% at 18 Torr (2.4 kPa) when a slow-rising voltage pulse of -28 kV was applied (rise time: 21.3 micros). In the tandem-tube system, the laser output energy was 259.4 microJ and the efficiency was 0.11% at 18 Torr when a slow-rising voltage pulse of -48 kV was applied (rise time: 27 micros). 相似文献
94.
Summary
7,7-Dibromo-8,8-dicyanoquinodimethane (1) was synthesized successfully as orange needles. Its homopolymerization and copolymerization with styrene were investigated.
1 polymerized with AIBN and triethylamine, but not with BF3·Et2O. 1 copolymerized with styrene in a random fashion and Q and e values were estimated to be 336 and +1.45, indicating a highly conjugative, electron-accepting monomer.
Received: 29 March 2001 / Accepted: 12 April 2001 相似文献
95.
Transparent and colorless epoxy/silsesquioxane (SQ) hybrids were prepared by modifying bisphenol-A epoxy resin with two SQ type epoxy resins having different 3D structures, that is, double-decker SQ and cage SQ type epoxy resins. To compare these two hybrids, the cured resin modified with the imperfect ladder SQ epoxy resin was also prepared. The effects of the 3D-structure of the SQ moieties on the thermomechanical, optical and dielectric properties of the cured epoxy/SQ hybrids were investigated. Thus, the refractive index and dielectric constant of the hybrids significantly decreased with an increase in the contents of the SQ moieties. This is due to the introduction of Si atoms with a low atomic polarity and large intermolecular space that was estimated from the difference between the volume of the space surrounded by “Connolly surface” and the van der Waals volume of the SQ moieties. The glass transition temperature, T g, also decreased with the introduction of the SQ moieties, due to the increase in the intermolecular space. Thus, it was concluded that the performance of the epoxy/SQ hybrids depends not only on the SiO3/2 content, but also on the 3D structure of the SQ moieties. 相似文献
96.
97.
Takahito Itoh Keita Hirai Masashi Tamura Takahiro Uno Masataka Kubo Yuichi Aihara 《Journal of power sources》2008
The two different molecular weight hyperbranched polymers (HBP(L)-PA-Ac and HBP(H)-PA-Ac) with both phosphonic acid group as a functional group and acryloyl group as a cross-linker at the chain ends were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked electrolyte membranes (CL-HBP-PA) were prepared by their thermal polymerizations using benzoyl peroxide and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the low molecular weight CL-HBP(L)-PA membrane and the high molecular weight CL-HBP(H)-PA membrane were found to be 1.2 × 10−5 and 2.6 × 10−6 S cm−1, respectively, at 150 °C under dry condition, and showed the Vogel–Tamman–Fulcher (VTF) type temperature dependence. Both membranes were thermally stable up to 300 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurements using a single membrane electrode assembly cell with both cross-linked membranes were successfully performed. 相似文献
98.
Kawaguchi Munemichi Shinya Miyahara Masayoshi Uno 《Journal of Nuclear Science and Technology》2019,56(6):513-520
This study revealed melting behavior and thermal conductivity of four samples generated by sodium-concrete reaction (SCR). We prepared the samples using two methods such as firing mixtures of sodium (Na) and grinded concrete powder, and sampling depositions after the SCR experiments. In the former, the mixing ratios were determined from the past experiment. The latter simulated the more realistic conditions such as the temperature history and the distribution of Na and concrete. The thermogravimetry-differential thermal analyzer (TG-DTA) measurement showed the temperatures of the onset of the melting (solidus temperatures) were 865–942°C, but those of the samples containing metallic Na could not be clarified. In the two more realistic samples, the compression moldings in a furnace were observed. The observation revealed the softening temperature was 800–840°C and the solidus temperature was 840–850°C, which was 10–20°C lower than the TG-DTA results. The thermodynamics calculation of FactSage 7.2 revealed the solidus temperature was caused by melting of the some components such as Na2SiO3 and/or Na4SiO4 and NaAlO2. Moreover, the thermal conductivity was λ ~ 1–3 W/m-K, which was comparable to xNa2O - (1 - x)SiO2 (x = 0.5, 0.33, and 0.25), and that at 700°C was explained by NBO/T of Equation (1). 相似文献
99.
Masato Ohnishi Naoko Taguchi Junpei Gotoh Takahiro Uno Masataka Kubo Takahito Itoh 《Polymer Bulletin》2009,62(6):761-776
A β-2-methoxyethyl α-3-[tris(trimethylsiloxy)silyl]propyl itaconate (1) was synthesized successfully as a novel amphiphilic itaconate monomer, and its radical homopolymerization and copolymerization
with styrene (St) were investigated. The polymerization rate (Rp) is expressed with Rp = k[1]2.73[AIBN]0.51. Overall activation energy in the radical homopolymerization was determined to be 52.9 kJ/mol. The 1 copolymerized with St in bulk in a highly alternating tendency. The Q, e values of the 1 were obtained to be 1.05 and 0.69, respectively, and the 1 was found to be a conjugative and electron-accepting monomer. Membranes containing the 1 unit, prepared by the copolymerization of 1 with N-vinylpyrrolidone (NVP) and by the terpolymerization of 1, NVP, and 2-hydroxyethyl methacrylate, showed higher oxygen permeability than corresponding ones without the 1 unit, and also they have better transparency than membranes containing 3-[tris(trimethylsiloxy)silyl]propyl methacrylate
unit. 相似文献
100.
Hiroaki Muta Ken Kurosaki Masayoshi Uno Shinsuke Yamanaka 《Journal of Materials Science》2008,43(19):6429-6434
Nitride fuel is a promising nuclear fuel in fast breeder reactor (FBR) or accelerator-driven subcritical reactor (ADSR) system.
In this study, high-density UN pellets were prepared by Spark plasma sintering (SPS) technique. The sample density strongly
depended on the sintering temperature and pressure, and the pellets with 90% of theoretical density were easily obtained with
low sintering temperature and short sintering time without any milling process. The grain size and pore size were much smaller
compared with those for samples prepared by conventional sintering process. Despite of the small grain size, the thermal conductivity
remains the high value. The SPS process permits easy densification of nitrides without any deterioration of thermal and mechanical
properties, considered to be suitable as a preparation method of nitride fuels. 相似文献