Momentum analysis of wind energy concentrator systems

The momentum theory is applied to wind energy concentrator systems. Both the concentration of the mass flow through the turbine and the augmentation of the specific energy drop over the turbine are taken into account. It is shown that the power coefficient of a system can be written as the product of three factors: a mass concentration coefficient an energy augmentation coefficient and an extraction coefficient. By this splitting, the relative importance of the three components in the power output of a system can be analysed.     

基于LBP算子的虹膜特征提取方法

由于虹膜自身具备独特性和随机性,因此需要对其进行特征提取操作,找出具有识别意义的虹膜纹理信息并将其编码,然后依据特定的判决标准来判断两幅图像是否源于同一人,从而实现虹膜识别的功能。该文对传统LBP算子进行改进,极大程度上缩减了描述码维数,并结合位移差分图像匹配方法,得到一种快速、有效的特征方法。通过对CASIA虹膜数据库进行实验比较,该方法能够获得理想的识别效果。     

硫代葡萄糖苷的提取、分离和鉴定

硫代葡萄糖苷(硫苷)是一些植物特有的、具有较高生物活性的次生代谢物质。以紫菜薹为材料,经过杀酶、去蛋白质、提取、脱硫酸根等处理后,通过反相高效液相色谱-紫外检测/电喷雾离子化-质谱联用技术(HPLC/UV-ESI/MS),成功分离和鉴定出9种不同硫苷,且这9种硫苷的RSD(n=3)均小于3%,线性关系R2也均在0.99以上。     

乙醇酶法从番茄中提取番茄红素的研究

本研究采用乙醇酶法是从番茄中提取番茄红素，研究了酶和乙醇浸取提取方法，并对番茄红素的提取条件作了研究，确定了较佳工艺条件。     

丝瓜中的皂甙及其生物活性

详述了国内外丝瓜中皂甙的提取和分离过程,概括了其组成及结构和生物活性研究,并对丝瓜的利用前景进行了分析.     

COMPARISON OF MULTISTAGE EXTRACTION INSTALLATIONS WITH SEPARATION OF THE SOLID PHASE BETWEEN THE STAGES IN HOPS (HUMULUS LUPULUS L.) EXTRACTION

The multistage extraction installations using cross-flow and back-flow schemes are successful in hops extraction. Both types of extraction process have been investigated, comparing the installations in order to specify the most appropriate scheme and determine the number of stages required. A three stage extraction with separation of a part of the solid phase between the stages was carried out. The parameters of each extraction stage of a cross-flow and a back-flow installation were calculated. It was established that in the cross-flow scheme the third stage was unnecessary since a minimal part of the bitter substances was extracted in it and the extract yield was too low. Moreover in the cross-flow installations a very high extraction efficiency was achieved, (94, 67%) but with a large consumption of extracting solvent (3,24.10^?2m³/kg) whilst in the back-flow scheme the extraction efficiency was much lower (71,4%) but with a reduced solvent consumption (1,2.10^?2m³/kg). The comparison of both installations demonstrates that the back-flow scheme is not very successful and that it is advisable to use a cross-flow installation with one or at most two extraction stages. The results obtained enable the proposal of a more rational scheme of hops extraction, where a one or two stages cross-flow process with separation of a part of the solid phase results in a final granulated product, a mixture of the extract and partly extracted raw material.     

Extraction of ginger rhizome: kinetic studies with acetone

Ground sieved Jamaican ginger rhizome has been treated with acetone under various conditions and, in each case, the concentration of [6]-gingerol extracted was measured as a function of time. The results could be expressed by two intersecting first-order plots and an initial intercept, representing very rapid initial extraction, followed by a fast stage and a subsequent slow stage. At 30°C the rate constant of the slow stage was c. 95 times smaller than that of the fast stage and its activation energy was 3.6 times larger. The fast stage was not affected by solvent flow into the ginger particles, or by an increase in the stirring speed. These findings, together with the fact that both first-order rate constants were inversely proportional to the square of the radius of the particles, pointed to [6]-gingerol diffusion through the solid ginger as the rate-determining step. The data could also be fitted by the equation of So and MacDonald (1986). The relevance of the research to the industrial production of ginger oleoresin is pointed out.     

溶剂萃取耦合FTIR技术快速分析食用油中微量水分的研究

研究应用溶剂萃取耦合傅里叶红外光谱(FTIR)技术建立快速分析食用油中微量水分的方法。数据显示乙腈是最佳萃取溶剂,其起始含水量300μg/g时对乙腈的萃取能力无明显影响。乙腈/油脂比例为1.5~2∶1效果较佳,定量基于差谱的二阶导数明显优于差谱,对于萃取水分的乙腈波谱中HOH弯曲振动1 631 cm-1最优,灵敏度高于OH伸缩振动3 630 cm-1和3 541 cm-1。对所有测试样品,FTIR法的结果与标准卡尔费休法高度一致,并表现出优良的准确性和精确性(标准差~30,变异系数3%)。研究表明溶剂萃取耦合FTIR快速分析食用油中微量水分切实可行。     

洋葱黄酮类化合物的水提工艺条件研究

采用水浸提法提取洋葱中的黄酮类化合物,用比色法测定洋葱中黄酮类化合物的含量,并对黄酮类化合物提取过程中各因素对收率的影响情况作了研究,其影响的主次顺序为料液比>浸提温度>浸提时间。     

虫草黄梨汁增强机体免疫调节功能的研究

系统地研究了以冬虫夏草，黄梨为主要原料，制成虫草黄梨汁的工艺过程。经一系列动物实验表明：虫草黄梨汁确有调节小鼠细胞免疫功能和调节小鼠单核－巨噬细胞吞噬能力的作用，是一种具有免疫调节作用的新型功能果汁饲料,具有较强的市场竞争力。