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51.
Synthesised E- and Z-ajoene were used to determine their amounts in food oils containing various fresh garlics. The best yield of E-ajoene (172.0 μg/g of garlic) and Z-ajoene (476.0 μg/g of garlic) was obtained from freshly prepared Japanese garlic with rice oil which was heated at 80 °C. Determination of E- and Z-ajoene from soybean oil containing 15% Japanese garlic samples prepared at 80 °C for 0.5 h gave the amount of E-ajoene (170.0 μg/g of garlic) and Z-ajoene (127.0 μg/g of garlic). After 9-month storage, 54.0% E- and 11.0% Z-ajoene remained in Japanese garlic with rice oil. Ajoene (0.1 mM) in ethyl acetate was incubated under UV-light (253.7 nm) for 3 days, 81.7% E- and 56.9% Z-ajoene remained. 4.3% and 0.5% E- and Z-ajoene remained when ajoene (0.1 mM in ethyl acetate) was incubated at 100 °C.  相似文献   
52.
目前在土木工程,建筑,汽车等领域里使用的复合材料中,玻璃纤维是用量最大的增强材料。由于保护地球环境的呼声日趋高涨,天然纤维被期待着代替源于石油而且再利用困难的玻璃纤维,成为绿色复合材料的必要材料之一。本文通过注射成型工艺制作了玻璃短纤维,大麻短纤维以及混杂型纤维增强复合材料,并在拉伸实验中应用两种不同频率的声发射技术检测了拉伸断裂特性。实验发现,随着大麻纤维的加入和混杂复合材料绿色度的增加,复合材料的拉伸弹性模量随之线性增大,而拉伸强度基本保持不变。当大麻纤维的含量超过20wt%的时候,拉伸强度开始降低。在不同频率的声发射实验中,混杂型复合材料的声发射事件的产生都比单一纤维增强型复合材料要来的晚,也就是说,纤维的混杂有助于推迟微裂纹的产生。  相似文献   
53.
BACKGROUND: The behavior of cadmium in ecosystems needs to be monitored because of the human toxicity of this heavy metal. The need recently arose for a simple and quick on‐site test for trace levels of Cd in food and environmental samples. In response, an immunochromatographic assay kit for detecting Cd was manufactured by Kansai Electric Power Co. of Japan. This kit uses the antigen–antibody complex reaction between the Cd–EDTA complex and an anti‐Cd–EDTA antibody and shows the results in terms of the degree of color developed on a test paper. We previously reported the successful use of this kit to determine Cd concentrations in brown rice. Here, we applied the kit to the determination of Cd concentrations in rice foliage and soil. RESULTS: Cadmium in rice foliage was not extracted successfully by the method used for brown rice. However, it was successfully extracted by 0.1 mol L?1 HCl solution at a rice foliage:HCl ratio of 1:20, and coexisting metals were removed sufficiently by the column treatment. The Cd concentrations determined by immunochromatographic assay were well correlated with the values obtained by acid decomposition and inductively coupled plasma mass spectrometry. The 0.1 mol L?1 HCl‐extractable Cd concentration in soil was also determined successfully with the kit. CONCLUSION: Approximate Cd concentrations in rice plants and 0.1 mol L?1 HCl‐extractable Cd concentrations in soil can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2009 Society of Chemical Industry  相似文献   
54.
The heterogeneous phase transition of the organic vapours, cyclohexane and p-xylene, on a cold substrate was observed by cooling the substrate at a slow rate under reduced pressure conditions. Either organic vapour at a vapour pressure lower than 130 Pa formed directly solid crystals but p-xylene vapour at a higher vapour pressure formed liquid condensates with subsequent formation of solid crystals. The dependence of the critical supersaturation ratios on the critical temperatures and the physical properties of the organic vapours has been clarified by the equation derived on the basis of classical nucleation theory.  相似文献   
55.
The applicability of a powerful but still easy to use technique, based on a phenomenological theory of viscoelasticity, for processing and analyzing dynamic mechanical data of some rice gels was investigated. Based on this theory a continuous relaxation spectra was generated by application of Tikhonov regularization procedure on continuous Maxwell model. Interpretation of relaxation spectra in terms of number of peaks, its peak intensity H(λ) and appearance of its main distribution peak and magnitude of equilibrium elasticity modulus (Ge) of continuous Maxwell model was found to appropriately reflect main peculiarities of the viscoelastic behavior of rice starch gels. An increase in number of peaks in the relaxation spectra was observed for starch gels having higher amylose content indicating the creation of more heterogeneous structure. H(λ) and Ge values also increased with increase in amylose content demonstrating a transition of the system to more stable state like a gel.  相似文献   
56.
Previously, we noted significant differences in the behavioral patterns of mice fed safflower oil with a very low alpha-linolenate/linoleate ratio and perilla oil with a high alpha-linolenate/linoleate ratio from mothers to offsprings. In this report, we compared the behavior and drug responses in mice fed diets containing six different vegetable oils-corn, rapeseed, soybean, safflower, perilla and a mixture of perilla and safflower oils- for a relatively short period: 8 months after weaning. Soybean oil is a component of most conventional diets and was used as a control. The alpha-linolenate/linoleate ratios of the oils appeared to affect the locomotor activities in a wheel cage: the activity decreased in the order of safflower, the mixture (1:1) and the perilla oil groups. However, the rapeseed oil group exhibited much higher locomotor activity than that expected from the alpha-linolenate/linoleate ratio. Additionally, the rapeseed oil group exhibited unusual behavior patterns, including higher ambulation and rearing activities, faster acquisition of the water maze task and slower habituation behavior as compared with the control group. Susceptibility to pentobarbital anesthesia tended to be higher in the rapeseed oil group. The differences in the alpha-linolenate/linoleate ratios of these oils alone do not account for the observed differences in the behavioral patterns among the six dietary groups. Although we cannot exclude the possibility that the observed behavioral anomaly is due to the unique fatty acid composition of rapeseed oil, we speculate that a factor(s) other than fatty acids in rapeseed oil affected nervous system functions.  相似文献   
57.
A yeast-like fungus Aureobasidium pullulans var. melanigenum strain ATCC 20524 produces an extracellular acidophilic endo-1,4-beta-xylanase with an optimum pH of 2.0 [Ohta et al., J. Biosci. Bioeng., 92, 262-270 (2001)]. The xynI cDNA encoding the precursor protein (XynI) was expressed in the methylotrophic yeast Pichia pastoris under the control of the alcohol oxidase I gene promoter. The 34 amino acid prepro-signal peptide of the A. pullulans XynI directed the efficient secretion of 178 mg of active xylanase per liter of the culture medium. The secretion level of the xylanase with its own signal peptide was comparable to that of the mature protein fused to the prepro leader from Saccharomyces cerevisiae alpha-mating factor and twofold higher than that of the mature protein fused to the pre-type signal peptide from P. pastoris acid phosphatase. The N-terminal amino acid sequence and the apparent M(r) of 24 kDa of the secreted recombinant protein indicated the native-like processing of the A. pullulans XynI signal sequence in P. pastoris. The three-dimensional model and mutational analysis of the xynI gene product showed that Asp-73 and Glu-157 residues located at the upper and lower edges of the active site cleft, respectively, play a significant role in its low pH optimum.  相似文献   
58.
A new fast‐seeking control method for the two‐stage actuator system in an optical disk drive has been developed. Fast seeking is performed by means of velocity control in two modes. The lens velocity in the first mode, which is estimated using a multirate observer, is equal to the pickup unit velocity, and it is controlled in order to prevent the lens from vibrating. The lens velocity in the second mode is equal to the specified target velocity, and it is controlled in order to improve the laser‐spot positioning accuracy. A DVD‐ROM drive is tested to confirm that the control system we propose significantly improves the seeking capabilities. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(3): 64–71, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21244  相似文献   
59.
Abstract

Ba1?x Sr x TiO3 thin film capacitors have been successfully prepared using rf-sputtering and a metal organic deposition (MOD) method. The structure, microstructure and composition of the BSTO films are presented. Films grown on lanthanum aluminate LAO(100) showed c-axis preferred growth orientation. Broad paraelectric-to-ferroelectric transitions were observed in films prepared by both methods. The tunability of the capacitance by means of an appplied electric field is examined using various capacitor geometries. A decrease in the capacitance exceeding 75% at 77 K was obtained from the MOD deposited films under an electric field strength of 0.3 MV/cm. On the other hand, the tunability of the capacitance in the rf-sputtered films ranged from 5 to 10% at 77 K and at 20 kV/cm, while it exceeds 50% in some films. The results are compared with the predictions of Devonshire's phenomenological theory.  相似文献   
60.
Accumulating evidence has demonstrated that the pathogenesis of epilepsy is linked to neuroinflammation and cerebrovascular dysfunction. Peripheral immune cell invasion into the brain, along with these responses, is implicitly involved in epilepsy. This review explored the current literature on the association between the peripheral and central nervous systems in the pathogenesis of epilepsy, and highlights novel research directions for therapeutic interventions targeting these reactions. Previous experimental and human studies have demonstrated the activation of the innate and adaptive immune responses in the brain. The time required for monocytes (responsible for innate immunity) and T cells (involved in acquired immunity) to invade the central nervous system after a seizure varies. Moreover, the time between the leakage associated with blood–brain barrier (BBB) failure and the infiltration of these cells varies. This suggests that cell infiltration is not merely a secondary disruptive event associated with BBB failure, but also a non-disruptive event facilitated by various mediators produced by the neurovascular unit consisting of neurons, perivascular astrocytes, microglia, pericytes, and endothelial cells. Moreover, genetic manipulation has enabled the differentiation between peripheral monocytes and resident microglia, which was previously considered difficult. Thus, the evidence suggests that peripheral monocytes may contribute to the pathogenesis of seizures.  相似文献   
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