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Limonoids in Pummelos [Citrus grandis (L.) Osbeck]   总被引:3,自引:0,他引:3  
Juice and seeds from 16 cultivars of mature pummelo fruits were analyzed for limonoid content. Pummelo juice contained an average of 18 ppm limonin and 29 ppm total limonoid glucosides. Compared to other juices, ptmnnelo contained very high concentrations of limonin and very low concentrations of limonoid glucosides. Limonin, nomilin, obacunone and trace amounts of deacetyhromilin were found in pummelo seeds. The 17–β-D-glucopyranoside derivatives (glucosides) of nomilin, nomilinic acid and obacunone were also present. Total limonoid aglycone concentration in the seeds ranged from 773 ppm to 9,900 ppm and total limonoid glucosides ranged from 130 ppm to 1,912 ppm.  相似文献   
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Studies on the Physical and Chemical Properties of Kiwi Fruit Starch   总被引:2,自引:0,他引:2  
The kiwi fruit starch consisted of small round granules with an average size of 5.5μ, and was composed of 14.4% moisture, 0.17% crude protein, 0.11% lipid and 0.14% ash. The phosphorus, content was 25.5 mg/100g, which was the highest concentration of the minerals. The amylose content was 10.8% and the X-ray diffraction pattern was B-type. The gelatinization temperature, obtained by DSC measurement, was 72°C. The properties of the fully gelatinized form and the low degree of retrogradation were observed by 13C-NMR analysis. Free fatty acids detected in the lipid component of the starch were oleic, palmitic, linolenic, linoleic, and stearic acids.  相似文献   
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Gigacycle fatigue properties of 1800 MPa class spring steels   总被引:2,自引:0,他引:2  
Fatigue tests up to 108 cycles were carried out for two spring steels (Heats A and D1) and one valve spring steel (Heat F) with tensile strength, σ B, of 1720, 1725 and 1764 MPa, respectively. The size and composition of inclusions in Heats Dl and F were controlled. The surface‐type fracture occurred at shorter lives below 106 cycles, while the fish‐eye‐type fracture occurred at longer lives. The fatigue limit, σ W, at 108 cycles was 640 MPa for Heats A and D1 and 700 MPa for Heat F. Al2O3 inclusions for Heat A and both TiN inclusions and matrix cracks, i.e. internal facets, for Heat F were observed at the fish‐eye‐type fracture sites, while only matrix cracks were observed for Heat Dl. ODA, i.e. optically dark area, which is considered to be related to hydrogen effects, were formed around Al2O3 and TiN inclusions. Fatigue tests were also conducted after specimens were heated up to 573 K in high vacuum of 2 × 10–6 Pa. The heat treatment eliminated matrix cracks for Heat D1 and the fatigue limit at 108 cycles recovered to the estimated value of 920 MPa from the equation σ w= 0.53 σ B for the surface fracture. These results suggest that inclusions control and hydrogen influence the gigacycle fatigue properties for these high strength steels. In addition, it is expected that the creation of a martensite structure with a high resistance to hydrogen effects in the inclusion‐controlled steel could achieve the higher fatigue limit estimated for the surface‐type fracture.  相似文献   
5.
Preparation of Fermented Soybean Curd using Stem Bromelain   总被引:7,自引:0,他引:7  
Preparation of fermented soybean curd using stem bromelain as coagulant of soy milk and an enzyme to improve the taste was investigated. After 60 days at 15°C ripening reached approximately 30-40% in curds which had stem bromelain added. The amino acids liberated in highest concentration were glutamic acid, leucine, lysine, alanine, and phenylalanine. Proteolytic activity from stem bromelain remained in the ripened curds, and activity from microorganisms appeared upon ripening. The recoveries of curds which had stem bromelain added were lower than that of a curd, which did not contain any stem bromelain.  相似文献   
6.
The visible spectra of a series of 1,4-disubstituted benzoanthraquinone dyes in benzene solution has been measured. The position of the absorption maxima of the dyes has been found to be well correlated with a mean ionization potential of the substituent groups. An annelation of anthraquinone dyes in the position of 2, 3 or 6, 7produced a small hypsochromic shift, while 5,6-annelation produced a large bathochromic shift. The additive properties on the absorption maximum of dibenzoanthraquinone dyes were also observed.  相似文献   
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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   
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The effective pore radius in screen-wick heat pipes was investigated, which is very important for the prediction of maximum heat transfer rates due to capillary limitation. An equation for the effective pore radius of the screen wicks was derived based on the model of the screen geometry. The capillary height for stainless steel and phosphor bronze screens was measured using water, ethyl alcohol, and Freon 113 as the test liquids. The effect of surface treatment (acid cleaning and oxidation) on the capillary height was also examined. From the comparison of the experimental data for water and ethyl alcohol with those for Freon 113, it was indicated that the contact angle was 24.2° for water and 16.9° for ethyl alcohol. Consequently, it was found that the effective pore radius of the screen wicks could be predicted fairly well from the expression presented in this study, and that the contact angle should be taken into consideration to evaluate the maximum capillary pressure accurately.  相似文献   
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