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91.
The performance of an experimental pilot-scale electrochemical reactor using a rotating cylindrical electrode equipped with wiper blades is described. Data obtained from monopolar depositing and bipolar stripping—depositing of copper from dilute aqueous electrolytes are presented and certain economic aspects of metal recovery are discussed. 相似文献
92.
The ionic conduction in sintered Bi2O2-Y2O3 was investigated by measuring the conductivity and the emf of an oxygen concentration cell using the specimen tablet as electrolyte. The face centred cubic phase in this system was found to show high oxide ion conduction accompanied by a little electronic conduction when exposed to air. This phase was stable with a composition of 25 ~ 43 mol % Y2O3 over a wide range of temperatures, and the oxide ion conductivity increased with decrease in Y2O3. The conductivities of (Bi2O3)0.75 (Y2O3)0.25 were 1.6×10?1 Ω?1 cm?1 at 700°C and 1.2×10?2 Ω?1 cm?1 at 500°C values which are many times higher than those of stabilized zirconia (ZrO2)0.90(Y2O3)0.10 at corresponding temperatures. Specimens containing less than 25 mol % Y2O3 showed a phase transition at 700 ~ 580°C and the conductivities decreased remarkably below these temperatures. High oxide ion conduction in the fcc phase is attributed to the migration of oxide ion vacancies which were present in an appreciable amount. 相似文献
93.
Somsak Vivatpanachart Hiroyasu Nomura Yutaka Miyahara Hisatsugu Kashiwabara Masato Sakaguchi 《Polymer》1981,22(7):896-901
E.s.r. spectra of chain-end spin labels on the surface of polyethylene powder were obtained for high and low density polyethylene samples at various stages of heat treatment process. The subsequent crystalline structures of the samples were examined with wide angle and small angle X-ray diffraction spectra. The effects of annealing on the motion of the labels were dependent on annealing temperature and the type of the samples. Higher temperature annealing decreased the rotational correlation times (τc) and their activation energy in high density polyethylene but did not affect those of low density polyethylene. Melting decreases the values of τc and ΔE for both high an low density polyethylene samples. The cause of these decreases were attributed to the changing of the sites of the chain-end labels. The motion of the labels appeared to be influenced by the local segmental motion of the polymer main chains. 相似文献
94.
Masaru Takahashi Tetsu Nakatani Shinji Iwamoto Tsunenori Watanabe Masashi Inoue 《Applied catalysis. B, Environmental》2007,70(1-4):73-79
The solvothermal reaction of mixtures of aluminum isopropoxide (AIP) and gallium acetylacetonate (Ga(acac)3) directly yielded the mixed oxides of γ-Ga2O3-Al2O3. In the solvothermal synthesis, the crystal structure of mixed oxides was controlled by the initial formation of γ-Ga2O3 nuclei. The mixed oxides prepared in diethylenetriamine have extremely high activities for selective catalytic reduction (SCR) of NO with methane as a reducing agent. With increasing crystallite size of the spinel structure, the catalytic activity increased. The ratio of the amount of methane consumed by combustion to total methane conversion was proportional to the density of acid sites on the surface of the mixed oxides. The mixed oxide catalysts prepared in diethylenetriamine had lower densities of acid sites and showed a higher methane-efficiency for CH4-SCR than those prepared in other solvents. These catalysts maintained their high activity even when the reaction was carried out under the severe conditions (i.e., high space velocity and low NO concentration). 相似文献
95.
Joo-Young Lee Yota Yamamoto Riichi Oe Su-Young Son Hitoshi Wakabayashi Yutaka Tochihara 《Ergonomics》2014,57(8):1213-1221
The purpose of this study was to investigate the physiological and subjective responses of the European, Japanese (JPN) and US firefighters' helmet, gloves and boots for international standardisation. Three experimental conditions were evaluated (clothing mass: 9.4, 8.2 and 10.1 kg for the three conditions, respectively) at the air temperature of 32°C and 60% relative humidity. The results showed that there was no significant difference among the three conditions in oxygen consumption, heart rate, total sweat rate, rectal temperature and mean skin temperature, whereas peripheral temperatures and subjective perceptions were lower in the JPN condition than in the other conditions (P < 0.05). These results indicate that a 0.5-kg reduction in helmet mass and a 1.1-kg reduction in boot mass during exercise resulted in a significant decrease in head and leg temperatures and subjective perceptions, while a 1.9-kg reduction in total clothing mass had insignificant influences on the metabolic burden and overall body temperature. 相似文献
96.
Takaaki Tsurumi Young-Bae Kil Kouhei Nagatoh Hirofumi Kakemoto Satoshi Wada Sadayuki Takahashi 《Journal of the American Ceramic Society》2002,85(8):1993-1996
The material coefficients of "soft" and "hard" lead zirconate titanate (PZT) ceramics were determined as complex values by the nonlinear least-squares-fitting of immittance data measured for length-extensional bar resonators. The piezoelectric d -constant should be a complex value to obtain a best fitting between observed and calculated results. Because the elastic, dielectric, and piezoelectric losses determined in this process were not "intrinsic" losses, a calculation process to evaluate the "intrinsic" losses was proposed. It was confirmed that the intrinsic losses were smaller than the corresponding extrinsic losses. The intrinsic piezoelectric loss existed in both soft and hard PZTs; ∼50% of the loss of piezoelectric d -constant was derived from the elastic and dielectric losses. The most notable difference between the soft and hard PZTs was observed in their elastic losses. 相似文献
97.
The matrix concept was used to characterize the chromatographic rules in the elution of molecular species of triglyceride.
To prove the hypothesis experimentally, cacao butter, palm oil, linseed oil, olive oil, rapeseed oil and triglyceride of “Ogonori”
(Gracilaria verrucosa) were examined. A matrix model was suggested to help determine the individual molecular species of naturally occurring triglycerides. 相似文献
98.
Studies are reported of the effect of an essential fatty acid (EFA) deficiency on synthesis of triglycerides (TG) and phospholipids
(PL) and secretion of these compounds by livers of male Sprague-Dawley rats. Animals were fed a semipurified diet containing
corn oil or hydrogenated coconut oil (HCO) as the sole source of fat or no fat from weaning to 20 weeks of age. Liver function
of the animals in each group was compared by an isolated liver perfusion technique with perfusates containing erythrocytes
and linoleate, and in vivo experiments via tail vein injection of palmitate-3H. Perfusion experiments showed that an EFA deficiency reduced the ability of the liver to secrete TG and PL. Accumulation
of TG in the liver and its diminished secretion into the blood of EFA deficient animals were demonstrated by in vivo experiments
with palmitate-3H. The rate of conversion of linoleate to arachidonate and synthesis of PL was greater in livers of EFA deficient rats than
in the control, corn oil fed animals. The results suggest a relationship of EFA metabolism to lipid transport.
One of five papers to be published from the Symposium “Lipid Transport” presented at the AOCS Meeting, New Orleans, April
1970. 相似文献
99.
J. Kurashige N. Matsuzaki H. Takahashi 《Journal of the American Oil Chemists' Society》1993,70(9):849-852
The bioreactor system to interesterify edible oils and fats at an ultra-micro aqueous phase of 100 ppm and less was investigated.
The adsorption of lecithin, together with lipase onto a carrier, was effective for conducting the interesterifying reaction
efficiently for oils and fats in micro aqueous phase.
To improve the handling properties of palm oil at rather low temperature, palm oil was blended with canola or soybean oil,
and then these blended oils were modified by enzymatic selective interesterification in a solvent-free, ultra-micro aqueous
bioreactor system with an immobilized lipase that had 1,3-positional specificity. The effects of enzymatic interesterification
were confirmed by triglyceride determination, by solid fat content profiles and by cloud point profiles, which were also compared
to products of chemical interesterification. The improvement in the fluidity of blended oils with canola oil by the enzymatic
reaction was bigger than with soybean oil, and chemical interesterification had no effects on the fluidity of blended oils. 相似文献
100.
Uniaxially oriented thin films of poly(ethylene terephthalate) (PET), poly(ethylene 2,6-naphthalene dicarboxylate) (PEN) and their blends were prepared by applying shear strain to their respective melts, and the resulting morphologies were studied by transmission electron microscopy. Selected-area electron diffraction of each film revealed well-defined uniaxial orientation of polymer chains in the shearing direction. In the uniaxially oriented thin film of PEN, stacked-lamellar structure with the average long period of 27 nm consisting of a crystalline region about 15 nm thick and an amorphous one about 12 nm thick was found here and there in the dark-field image: PEN-type. On the other hand, stacked-lamellar structure was rarely observed in the case of PET: PET-type. In PET/PEN blends, the morphologies changed from the PET-type to the PEN-type with increasing content of PEN. 相似文献