Interaction of Fragrance Materials With 2-Hydroxypropyl-beta-Cyclodextrin by Static and Dynamic Head-space Methods

The stability constants for the inclusion of fragrance materials with 2-hydroxypropyl-beta-cyclodextrin (2HP-beta-C yD) in aqueous solution have been determined by the static head-space method. The 1:1 stability constants obtained by this method were in reasonable agreement with the corresponding values in the literature. In addition, the release profiles of fragrance materials from 2HP-beta-CyD aqueous solution were investigated using the dynamic head-space method. It was found that the suppression of the fragrance materials release was dependent on their stability constants.     

Water Vapor Permeability of Whey Protein Emulsion Films as Affected by pH

The water vapor permeability (WVP) of whey protein isolate-beeswax emulsion films was investigated as related to pH. Lower WVP was observed for films cast from solutions at pH 7.0. When pH of the film-forming solution was lowered, resulting film WVP increased. At the isoelectric point, WVP was the highest. As pH of the emulsion approached pI, a sharp change in viscosity occurred due to an increase in protein aggregation. This increase in viscosity probably lowered lipid mobility and reduced interconnectivity among lipid droplets, resulting in the higher WVP. For minimum WVP, such films should be applied at pH different from pI.     

Prevention of Clostridium botulinum Type A, Proteolytic B and E Toxin Formation in Refrigerated Pea Soup by Lactobacillus plantarum ATCC 8014

The ability of Lactobacillus plantarum ATCC 8014 to inhibit Clostridium botulinum toxin production in pea soup was investigated. Soup containing C. botulinum spores (10³/g) with and without L. plantarum (10⁶/g) were evaluated. Soup containing only type A spores was toxic on days 1 and 2 when incubated at 35°C and 25°C, respectively. Soup containing only proteolytic type B spores was toxic on days 2 and 5 at 35°C and 25°C, respectively. Soup containing only type E spores was toxic at 25°C, 15°C, and 5°C in 7, 7, and 63 days respectively. No toxin was found in soup containing C. botulinum spores plus L. plantarum at any temperature studied.     

Stability and Antioxidant Activity of Beta Carotene in Conventional and High Oleic Canola Oil

Conventional canola oil (CO) and high oleic canola oil (HOCO) were stored under autoxidative and photooxidative conditions, β-carotene was added at 0 to 120 ppm. The oils were diluted in mobile phase and injected onto an HPLC column to track β-carotene changes over time. Peroxide values were followed to assess the oxidative stability of the oils. β-carotene was more stable in HOCO than in CO under autoxidative conditions, but no difference between oils was observed under photooxidative conditions. The HOCO was more stable against autoxidation, and CO was more stable against photo-oxidation. Antioxidant activity was shown by β-carotene in both oils, which contained natural tocopherols, during both autoxidative and photooxidative conditions.     

Starch Retrogradation and Texture of Cooked Milled Rice During Storage

The effect of storing cooked Bengal and Cypress milled rice at -13, 3, 20, and 36 °C on texture and degree of starch retrogradation was investigated. Cooked rice firmness increased, while stickiness decreased, during storage at -13 and 3 °C. Starch retrogradation, measured with a differential scanning calorimeter, was observed for both cultivars during storage at -13 and 3 °C, but not at 36 °C. At 20 °C, retrogradation occurred in Cypress, but not in Bengal. Starch retrogradation showed positive linear trends with firmness for both cultivars at all storage temperatures (R²= 0.80) and with stickiness for Bengal stored at -13 and 3 °C and for Cypress stored at 3 and 20 °C (R2 = 0.88).     

油脂氧化稳定性的研究

用Ｒａｎｃｉｍａｔ仪器测定了油脂氧化稳定性。结果表明,温度的高低,脂肪酸不饱和度,抗氧化剂和增效剂的使用,均与油脂氧化稳定性有着密切的关系。     

自密实混凝土重力坝浇筑层间稳定性分析研究

自密实混凝土重力坝是用流动性较强的混凝土在堆石之间填充并分层浇筑而成.为了研究浇筑层间的稳定性,采用刚体平衡原理和第三强度理论分别对自密实混凝土重力坝层间的抗滑稳定性和堆石间拉力情况进行了分析研究.结果表明:随着坝体层间堆石相对接触面积α的增大,层间抗滑稳定系数K逐渐增大,但是增加的幅度处在一个稳定的范围之内;随着堆石...     

暴雨情形下含裂隙土质边坡的瞬态稳定性

以山西省安太堡露天煤矿某地质剖面为例,采用Slide软件对暴雨情形下含裂隙土质边坡的稳定性进行分析,确定边坡潜在滑动面的位置,合理布置促使边坡发生推移式滑坡和牵引式滑坡的裂隙,应用MIDAS/GTS软件模拟分析降雨条件下的坡体应变规律和边坡稳定情况。结果表明:随着降雨入渗,边坡塑性区自坡脚向上部不断发展,直至形成贯通的塑性区;在持续降雨1.5 d时,边坡的稳定性最差,存在表层滑动可能;所提出的边坡裂隙布置方式更能反映含裂隙土质边坡在暴雨情形下的实际情况。     

治理深圳河一期工程中的软基处理

在治理深圳河一期工程中, 淤泥土层采用真空预压, 强度增长了50%以上。由于成功地进行了新河道开挖与堤坝填筑, 致使边坡的安全稳定得到保证。用真空预压解决软基边坡的稳定问题, 在国内尚属首例。     

用地质力学模型研究三峡升船机上闸首基础稳定问题

 用三维地质力学模型试验技术研究了三峡升船机上闸首基础稳定性。详细模拟了上闸首建筑物、建筑物基础岩体、岩体中断层、陡倾角裂隙及缓倾角裂隙的几何形态和它们的复杂力学性质还模拟了自重渗透水压力、上游水压力的作用，模型几何相似比尺为120。试验测得，三峡升船机上闸首基础稳定超载安全系数达3.6。