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51.
大豆脂肪氧化酶酶活性变化研究   总被引:1,自引:0,他引:1  
采用分光光度法对大豆中三种脂肪氧化酶(同工酶)进行检测并测定脂肪氧化酶活性,研究表明:大豆粉碎后随着贮存时间的延长,脂肪氧化酶活性逐渐降低,大豆发芽后脂肪氧化酶活性降低了43%.  相似文献   
52.
53.
La(3)Ta(0.5)Ga(5.5)O(14) (LTG) single crystals, which have no phase transition up to the melting point, were heat-treated in air at temperatures from 1000°C to 1450°C for 10 h. LaTaO(4) (LT) and LaGaO(3) (LG), which coexist with LTG in the three-phase region on the Ga-poor side, precipitated on the surface of the crystal for heat treatments above 1300°C because of Ga evaporation during the heat treatment. The Ga-poor state near the surface of the 1450°C heat-treated specimen was confirmed by electron probe micro-analysis measurements. The electrical resistivity of LTG single crystals decreased by heat treatment in the range of 1000°C to 1200°C for 10 h in air, where no precipitation was observed, whereas the resistivity increased with heat treatment over 1400°C for 10 h in air. The electrical resistivity of the Ga-poor surface region was higher than that of the interior.  相似文献   
54.
Additive effects of glass powder upon the product yields and chlorine distribution after liquefaction of hydrothermally pretreated mixed waste (HMW) are compared with liquefaction of HMW with any one of water, quartz sand, or glass powder plus water. As a result, addition of either water or quartz sand did not affect liquefaction and dechlorination of HMW. Further, water (5 g) addition did not enhance liquefaction and dechlorination of HMW with glass powder. On the other hand, after liquefaction of HMW with glass powder, the yields of chlorine in the gas and water insoluble constituents decreased and the chlorine yield in the water-soluble constituent increased significantly. Because sodium in glass powder dissolved in a small amount (0.5 g) of water resulted from dehydration of HMW during liquefaction. Further, hydrogen chloride derived from polyvinylchloride in HMW was neutralized by ion exchange between H(+) and Na(+) dissolved in a small amount of water forming NaCl in the Residue (water-soluble) constituent. Therefore, most of chlorine in HMW was removed easily by water extraction of the Residue constituent after liquefaction of HMW with glass powder. Further, upgrading of HMW into the oil constituent was enhanced due to inhibition of production of chlorine containing organic compounds. Accordingly, it was clarified that glass powder was the most effective additive for liquefaction and dechlorination of HMW.  相似文献   
55.
A method of loss calculation for induction motors is proposed. The combined 3D–2D time‐stepping finite element analysis is carried out to obtain the copper loss and the time variation of the magnetic field in the motor. The iron loss is calculated approximately considering the time variation of the magnetic field direction and the minor hysteresis loops caused by the time‐harmonic fields using practical computer resources. The proposed method is applied to four types of induction motors, which are the solid rotor induction motors with/without slot and the cage induction motors with/without skew. The measured and the calculated total losses and the iron losses agree well in all cases. The differences of the loss distributions of each motor are also compared and investigated. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(2): 63–73, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10305  相似文献   
56.
Recently, we have reported that anthocyanins show strong antioxidative activity, but no attention has been paid to anthocyanins from the viewpoint of the reaction mechanism of alkylperoxyl radicals; therefore, we investigated the reaction products of antioxidative anthocyanins (cyanidin 3-O-β-d-glucoside). Cyanidin 3-O-β-d-glucoside was reacted with 2,2′-azobis(2,4-dimet hylvaleronitrile) to generate the alkylperoxyl radicals, and the reaction products were isolated by high-performance liquid chromatography. The products were identified as 4,6-dihydroxy-2-O-β-d-glucosyl-3-oxo-2,3-dihydrobenzofuran and protocatechuic acid. Based on reaction products, the antioxidative mechanism of cyanidin 3-O-β-d-glucoside may be different from that of α-tocopherol; cyanidin 3-O-β-d-glucoside would produce another radical scavenger, as it would break down the structure and scavenge the radicals.  相似文献   
57.
To investigate the prevalence of attaching and effacing Escherichia coli, we examined 364 strains isolated from the feces of 9,684 patients with diarrhea at the Anjo Kosei Hospital in Japan for the presence of eaeA. Twenty-nine (8%) of the strains were eaeA positive. Of enteropathogenic E. coli (EPEC), 11 of the 87 (13%) strains were for the positive eaeA gene. The serotypes and the numbers of eaeA-positive strains among the strains tested were as follows: O26:H-(2/3), O55:H7 (4/4), O55:H-(2/ 2) and O128:H2(3/3). Two enterohemorrhagic E. coli (EHEC) strains (Verotoxin positive O157:H7) were also eaeA positive. Among 260 non-EPEC strains that were not categorized as diarrheagenic E. coli, 16 (6%) were eaeA positive. Those serotypes were as follows: O15:H2, O20:H6, O28:H28, O63:H6. O153:H7, O28:H6, O153:H19 and O157:H45. EPEC strains including O18:H7 and six other serotypes, enteroinvasive E. coli (EIEC), and enterotoxigenic E. coli (ETEC) were all eaeA negative.  相似文献   
58.
Because of the introduction of deregulation and competition in the electricity supply industry, large numbers of IPPs (Independent Power Producers) will get into the market. It has become much more important to be able to determine which generators are supplying a particular load, which generator is responsible for transmission line congestion, and what is each generator's contribution to the system losses. In this paper, we propose a way to calculate these contributions automatically. The applicability of the proposed technique is demonstrated using the EAST 10 47‐bus power system. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(3): 28–35, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10181  相似文献   
59.
Abstract— A new optical method for determining the pretilt angle ψ0, particularly on twisted‐nematic (TN) liquid‐crystal (LC) cells, is proposed. ψ0 was rapidly determined with good reproducibility on a TN‐LC cell by using a rotating analyzer optical system, a twist angle Φ, the azimuth of the director at a substrate, ϕ0, and the retardation Δnd as known values. The thickness d was also determined simultaneously with ψ0. ψ0 and d were determined within minutes. ψ0 was previously determined to be in the range of 0.1° with a standard deviation of 0.01°; this was obtained by repeating the measurement 50 times. The principle behind the determination and the experimental set up are described in detail.  相似文献   
60.
The genetic defect in a patient with hereditary type I protein S (PS) deficiency was investigated. All the exons and intron-exon junctions of the patient's PS gene were amplified by PCR and subjected to heteroduplex screening. Only the PCR product of exon 4 revealed heteroduplex bands. A novel nonsense mutation, Ser62 (TCA) to Stop (TGA) was found in exon 4. RT-PCR detected the aberrant mRNA in the patient's platelets, which was markedly reduced in amount and lacked the region of exon 4, suggesting that the nonsense mutation affected the mutated mRNA metabolism and induced exon skipping. The skipping of exon 4 causes an in-frame deletion of 29 amino acids which just construct the thrombin-sensitive region of the PS molecule. The loss of such an important domain as well as the quantitative decrease in the mutated mRNA appear to be responsible for the type I PS deficiency in this patient.  相似文献   
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