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51.
Yoshikazu Takaku Lazuardi Felicia Ikuo Ohnuma Ryosuke Kainuma Kiyohito Ishida 《Journal of Electronic Materials》2008,37(3):314-323
Chemical reactions between Cu substrates and Zn-Al high-temperature solder alloys, Zn-4Al and Zn-4Al-1Cu (mass%), at temperatures
ranging from 420°C to 530°C were experimentally investigated by a scanning electron microscope using backscattered electrons
(SEM-BSE) and an electron probe microanalyzer (EPMA). Intermediate phases (IMPs), β(A2) or β′(B2), γ(D82), and ε(A3) phases formed and grew during the soldering and aging treatments. The consumption rate of the IMP for Cu substrates
is described by the square root of t in both the alloys, while the additional Cu in the molten Zn-Al alloy slightly suppresses the consumption of Cu substrates.
The growth of IMPs during soldering treatment is controlled by the volume diffusion of constituent elements, and its activation
energy increases in the order of Q
ε < Q
γ < Q
β. In view of the aging process, the growth of IMPs is considered to be controlled by the volume diffusion. In particular,
the layer thickness of γ rapidly grows over 200°C, although the thickness of the β layer grows very slowly. 相似文献
52.
53.
Identification of yeast strains isolated from marcha in Sikkim, a microbial starter for amylolytic fermentation 总被引:1,自引:0,他引:1
Tsuyoshi N Fudou R Yamanaka S Kozaki M Tamang N Thapa S Tamang JP 《International journal of food microbiology》2005,99(2):135-146
Marcha or murcha is a traditional amylolytic starter used to produce sweet-sour alcoholic drinks, commonly called jaanr in the Himalayan regions of India, Nepal, Bhutan, and Tibet (China). The aim of this study was to examine the microflora of marcha collected from Sikkim in India, focusing on yeast flora and their roles. Twenty yeast strains were isolated from six samples of marcha and identified by genetic and phenotypic methods. They were first classified into four groups (Group I, II, III, and IV) based on physiological features using an API test. Phylogenetic, morphological, and physiological characterization identified the isolates as Saccharomyces bayanus (Group I); Candida glabrata (Group II); Pichia anomala (Group III); and Saccharomycopsis fibuligera, Saccharomycopsis capsularis, and Pichia burtonii (Group IV). Among them, the Group I, II, and III strains produced ethanol. The isolates of Group IV had high amylolytic activity. Because all marcha samples tested contained both starch degraders and ethanol producers, it was hypothesized that all four groups of yeast (Group I, II, III, and IV) contribute to starch-based alcohol fermentation. 相似文献
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57.
Ryosuke Iwai Yoko Kumagai Masashi Fujiwara Shigeyuki Wakitani Mutsumi Takagi 《Journal of Bioscience and Bioengineering》2010,110(5):593-596
High-expression plasmid vectors for human mesenchymal stem cells (MSCs) were constructed by combination of cytomegalovirus immediate-early enhancer with cellular promoters. MSCs transfected with the vector showed higher transgene production of a cytokine, which increased the differentiation level to chondrocytes. 相似文献
58.
目的:通过试食实验,评价沙拉酱对人体部分血脂指标影响的效果。方法:采用自身对照设计的方法。47例18~22岁青年健康男性参与为期70d的试食实验。在不影响试食者饮食习惯的前提下,每日提供15g沙拉酱。分别在实验前及试食过程中的30、60、70d后分别进行检测。并于实验结束后37d再进行一次检测,以观察试食者在食用沙拉酱后血脂指标的变化。结果:试食至30d,试食者低密度脂蛋白胆固醇(LDL-C)含量显著下降(P<0.01)。试食至60d,血清总胆固醇(TC)、甘油三酯(TG)的含量显著上升(P<0.01),LDL-C值显著下降(P<0.01)。试食至70d,TC、TG含量显著上升(P<0.01)、高密度脂蛋白胆固醇(HDL-C)含量显著上升(P<0.01)。结论:在实验所指定的剂量下,沙拉酱未对人体血脂造成不良影响。值得注意的是,试食至50d时,由于节日原因,试食者饮食结构发生突变,饮酒和动物性脂肪摄入较多,导致第60天及第70天检测所得数据中TC和TG等有异常变化,证明饮食结构的变化直接影响血脂指标的变化。本次试食实验的数据表明,沙拉酱对提高HDL-C含量、降低LDL-C含量具有一定的促进作用。 相似文献
59.
Goto T Horita M Nagai H Nagatomo A Nishida N Matsuura Y Nagaoka S 《Molecular nutrition & food research》2012,56(3):435-445
Scope Recent studies have reported that tiliroside, a glycosidic flavonoid, possesses anti‐diabetic activities. In the present study, we investigated the effects of tiliroside on carbohydrate digestion and absorption in the gastrointestinal tract. Methods and results This study showed that tiliroside inhibits pancreatic α‐amylase (IC50 = 0.28 mM) in vitro. Tiliroside was found as a noncompetitive inhibitor of α‐amylase with Ki values of 84.2 μM. In male ICR mice, the increase in postprandial plasma glucose levels was significantly suppressed in the tiliroside‐administered group. Tiliroside treatment also suppressed hyperinsulinemia after starch administration. Tiliroside administration inhibited the increase of plasma glucose levels in an oral glucose tolerance test, but not in an intraperitoneal glucose tolerance test. In human intestinal Caco‐2 cells, the addition of tiliroside caused a significant dose‐dependent inhibition of glucose uptake. The inhibitory effects of both sodium‐dependent glucose transporter 1 (SGLT1) and glucose transporter 2 (GLUT2) inhibitors (phlorizin and phloretin, respectively) on glucose uptake were significantly inhibited in the presence of tiliroside, suggesting that tiliroside inhibited glucose uptake mediated by both SGLT1 and GLUT2. Conclusion These findings indicate that the anti‐diabetic effects of tiliroside are at least partially mediated through inhibitory effects on carbohydrate digestion and glucose uptake in the gastrointestinal tract. 相似文献
60.
The quality loss suggested by Taguchi has been recognised as a new quality evaluation based on variable property instead of the quality evaluation based on traditional attribute property such as the proportion of nonconforming items. Some variable sampling inspection plans in order to assure the quality have been considered. As one of those sampling inspection plans, the single sampling plan with screening (SSPS) has been constructed for acceptance quality loss limit inspection scheme. Further, the repetitive group sampling plan with screening (RGSPS) has been developed for reducing the average total inspection (ATI). Although ATI by RGSPS has successfully been reduced in comparison with ATI by SSPS, RGSPS may sometimes increase the average sampling frequency (ASF) in return for reducing ATI. In this study, the stage-independent double sampling plan with screening (SIDSPS) based on the concept of the acceptance quality loss limit inspection scheme is proposed under the consideration of the trade-off between ATI and ASF. Through some numerical comparisons about ATI and ASF in SSPS, RGSPS, and SIDSPS, the usefulness of SIDSPS proposed in this study is confirmed. 相似文献