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板栗壳棕色素的提取及其相关性质研究 总被引:1,自引:0,他引:1
以乙醇作溶剂,用一次浸提法从板栗壳中提取天然棕色素.正交试验结果表明:提取时间2.5 h、浸提温度75℃、乙醇浓度40%、固液比1:20(g:mL)时,棕色素的提取率较高,为5.52%.对相关性质进行测定表明:所得棕色素溶于水、乙醇、甲醇,不溶于苯、丙酮、乙酸乙酯等溶液;PH值对棕色素影响不明显;棕色素水溶液有较好的耐光性耐热性及较好的抗氧化性抗还原性;金属离子Ca2+、Mg2+、Zn2+、Ba2+、Na+、K+对色素的颜色无明显影响,但金属离子Fe3+、Pb2+、Cu2+会与色素反应生成沉淀并褪色. 相似文献
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Charles Holland 《Architectural Design》2011,81(5):90-97
Charles Holland of FAT picks up the Post-Modern baton from Venturi Scott Brown and Charles Jencks and raises the neglected topic of taste. Though the way architecture is experienced by people is bound up with taste, it remains an area of discomfort for architects – tied up with awkward discussions of privilege and class. Holland shows how in FAT's Islington Square housing project the DIY taste of the residents was not only embraced, but fully accommodated. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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R.S. Prakasham P. Brahmaiah D. Nagaiah P. Srinivasa Rao Belum V.S. Reddy R. Sreenivas Rao Phil J. Hobbs 《International Journal of Hydrogen Energy》2012
Three low lignin containing bmr 3 derivatives, namely DRT 07K1, DRT 07K6 and DRT 07K15 developed through backcrossing were used along with the parent, bmr 3 source mutant (IS 21888) for evaluation of biohydrogen production. Results demonstrated that biohydrogen production varied amongst bmr derivatives under similar fermentation conditions. Significant negative correlation was observed between lignin content and fermentative biohydrogen production. All bmr derivatives with lower lignin content produced higher levels of biohydrogen compared to source bmr 3 (IS 21888) which has more lignin content. The maximum and a minimum biohydrogen production observed was 72 and 50 ml/g Total Volatile Solids (TVS) for the DRT 07K6 bmr3 derivative and bmr 3 (IS 21888) respectively. Acetate and butyrate were accounted >85% of volatile fatty acids, indicating acid type fermentations. Statistical analysis revealed that all bmr mutant derivatives with respect to source differ significantly in cumulative biohydrogen production, plant height, grain yield and lignin content. Biohydrogen production from biomass associated at least two different levels, one at lignin entanglement another at the polymeric nature of cellulose and hemicellulose. Further studies are necessary to determine the effect of biomass structure associated with different bmr traits on the microbial growth and biohydrogen production rate. 相似文献
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Development and psychometric evaluation of the Yale–Brown Obsessive-Compulsive Scale—Second Edition.
Storch Eric A.; Rasmussen Steven A.; Price Lawrence H.; Larson Michael J.; Murphy Tanya K.; Goodman Wayne K. 《Canadian Metallurgical Quarterly》2010,22(2):223
The Yale–Brown Obsessive-Compulsive Scale (Y-BOCS; Goodman, Price, Rasmussen, Mazure, Delgado, et al., 1989) is acknowledged as the gold standard measure of obsessive-compulsive disorder (OCD) symptom severity. A number of areas where the Y-BOCS may benefit from revision have emerged in past psychometric studies of the Severity Scale and Symptom Checklist. Therefore, we created the Yale–Brown Obsessive-Compulsive Scale—Second Edition (Y-BOCS–II) by revising the Severity Scale item content and scoring framework, integrating avoidance into the scoring of Severity Scale items, and modifying the Symptom Checklist content and format. One hundred thirty treatment-seeking adults with OCD completed a battery of measures assessing OCD symptom severity and typology and depressive and anxious symptomology. Interrater and test–retest reliability were assessed on a subsample of participants. The Y-BOCS–II showed strong internal consistency for the Symptom Checklist (Kuder–Richardson-20 = .91) and Severity Scale (α = .89). Test–retest and interrater reliabilities were both high (intraclass correlations > .85). Confirmatory factor analyses did not show adequate fit with previous models of the Y-BOCS. Exploratory factor analysis revealed a two-factor solution generally consistent with the Obsession and Compulsion Severity subscales. Construct validity was supported by strong correlations with clinician-rated measures of OCD symptom severity and moderate correlations with measures of worry and depressive symptoms. Taken together, the Y-BOCS–II has excellent psychometric properties in assessing the presence and severity of obsessive-compulsive symptoms. Although the Y-BOCS remains a reliable and valid measure, the Y-BOCS–II may provide an alternative method of assessing symptom presence and severity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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使用Miseq高通量测序技术对3个襄阳大头菜腌制液膜醭样品的细菌微生物群落结构进行了解析。在门水平上,变形菌门(Proteobacteria)和硬壁菌门(Firmicutes)平均含量分别为62.12%和34.13%。在属水平上,相对含量>1.0%的细菌属分别为盐单胞菌(Halomonas)、色盐杆菌属(Chromohalobacter)、海杆菌属(Marinobacter)、盐厌氧菌属(Halanaerobium)、四联球菌(Tetragenococcus)和碱杆菌属(Alkalibacillus),其相对含量为26.31%、16.49%、8.13%、24.87%、6.13%和1.16%。在操作分类单元水平(OTU)上,发现14个平均相对含量>1.0%的核心OTU,其中OTU4083(隶属于盐厌氧菌属)、OTU4400(隶属于色盐杆菌属)和OTU846(隶属于盐单胞菌属)的累计平均相对含量为39.50%。由此可见,襄阳大头菜膜醭中的细菌微生物主要由隶属于变形菌门和硬壁菌门的6个属构成,且膜醭共有大量的核心细菌菌群。 相似文献