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1.
探讨了料液比、pH值、温度、时间以及介质等因素对南瓜种子蛋白质溶出率的影响 .结果表明 :蛋白质的溶出率受pH值、介质的影响较大 ,其次为料液比、浸提温度和浸提时间 .初步确定南瓜种子蛋白质提取的较佳条件为 :料液比 1∶1 0 0 ,pH值 1 2 0的碱性条件下 ,37℃浸提 1 0h .  相似文献   

2.
应用微波萃取技术,以柚子皮为原料提取黄酮类化合物,用紫外分光光度法测定提取液中的黄酮类化合物的含量.在微波单因素浸提的基础上,采取正交优化试验,以探讨微波功率、料液比、微波处理时间、pH值、溶剂及溶剂的浓度对黄酮类化合物提取率的影响.正交实验表明,微波法提取黄酮类化合物的最佳条件是:微波功率是595W、微波处理时间20s、液料比为15:1、pH值为11、溶剂是浓度为80%的乙醇,在此条件下浸提,所得的黄酮类化合物含量为0.748%.在该工艺条件下,黄酮类化合物的得率比较高、所需要的时间短,是一种快速、高效、节能、环保的新型提取工艺.  相似文献   

3.
以茶鲜叶为原料,采用正交试验,研究了低咖啡因速溶红茶的加工工艺.通过综合评估,鲜叶添加比例以7∶3最为合适,即每70g脱咖啡因鲜叶中添加30g切碎的鲜叶作为酶源发酵制成的脱咖啡因红茶胚品质最佳.4个因素对茶黄素浸提影响的主次关系为pH值,温度,固液比,时间,对茶红素浸提影响的主次关系则为固液比,时间,pH值,温度.鲜叶加工低咖啡因速溶红茶浸提的最优工艺参数为温度95℃,浸提时间30min,固液比1∶15,pH值为5.5.通过感官审评,发现用鲜叶制的低咖啡因速溶红茶品质更佳,且其得率也达到了21.4%,与传统加工方法相比差异也不大,故此工艺可以应用到产业化生产速溶红茶中.  相似文献   

4.
微波辅助提取铁观音茶多糖及其抗氧化活性研究   总被引:2,自引:0,他引:2  
采用微波辅助方法提取铁观音茶多糖,并对其抗氧化活性进行了研究.通过正交实验考察了微波功率、时间、水浴浸提温度、料液比对多糖得率的影响,结果表明,铁观音茶多糖得率随微波功率和时间的增加而增大,随料液比的升高先增后降,最佳的微波处理条件为:微波功率375 W,时间180 s,水浴浸提温度60 ℃以及料液比1∶ 30.抗氧化活性实验结果表明,铁观音茶多糖对超氧阴离子和羟自由基有较好的清除效果,并且在一定范围内,其清除能力与质量浓度有明显的量效关系,实验范围内的微波处理对其抗氧化活性无显著影响.  相似文献   

5.
绿茶冲泡过程中咖啡碱的转移动态   总被引:1,自引:0,他引:1  
采用均匀试验设计,模拟中国绿茶消费者的泡饮方式,研究在冲泡过程中液料比、茶汤剩余百分比、加水温度、冲泡时间以及冲泡次数这5个因素对咖啡碱溶出量的影响.结果表明,除冲泡次数外,加水温度对咖啡碱的溶出量影响最大,其次为液料比和茶汤剩余百分比,冲泡时间影响较小.当温度高于90℃,液料比和茶汤剩余百分比为55∶1和30%时,咖啡碱溶出量最多;但无论用哪种冲泡方法进行冲泡,当冲泡4次时,咖啡碱溶出量均达到最大值.  相似文献   

6.
《河南科学》2016,(7):1097-1100
以桔梗多糖为研究对象,采用单因素及正交实验对微波辅助热水浸提桔梗多糖工艺进行了研究,分析了料液比、温度、提取时间、微波功率、粒度、微波时间等因素对多糖提取率的影响.实验结果表明传统热水提取法的最佳工艺条件:浸提温度80℃,提取时间240 min,粒度80目,料液比1∶20;微波辅助热水浸提桔梗多糖的最佳工艺条件:料液比1∶20,微波处理时间2 min,微波功率400 W,热水浸提温度80℃,粒度80目,热水浸提时间240 min.采取短时高频微波前处理利于多糖析出,再通过后续热水浸提,其多糖提取率为32.85%,高于传统热水浸提(16.59%)和微波提取(22.83%).  相似文献   

7.
微波法提取葛根黄酮的研究   总被引:3,自引:0,他引:3  
采用微波技术提取葛根黄酮,并运用了均匀设计方法研究了葛根黄酮的提取试验,考察了微波强度、浸提时间、提取液的醇度及料液比等因素对提取结果影响。通过回归数学模型确定了微波提取葛根黄酮的最佳工艺条件:微波功率0.63kW,浸提时间15min,料液比(体积)1:25,醇度20%。  相似文献   

8.
以马铃薯粉渣为原料,研究微波辅助提取果胶工艺.对比了液料比、提取pH值、微波加热时间、微波功率和硫酸铝用量对果胶提取率的影响,确定优化提取方案.结果表明,优化的提取条件为:液料比15∶1,提取pH值为2,微波加热时间为5 min,微波功率0.4 kW,硫酸铝用量7 mL,果胶提取率为1.853 7%,比传统提取方法时间缩短、产率提高、大量节约溶剂.  相似文献   

9.
微波辅助栀子黄色素的水浴浸提   总被引:1,自引:0,他引:1  
采用单因素实验法,研究了微波辐照下,原料粒度、微波功率、浸提液pH值,温度、时间等工艺条件对水浴浸提栀子黄色素的影响.在优化的工艺条件下,栀子黄色素的一次浸提率高于94%,两次浸提率超过99%,优于其它传统工艺.  相似文献   

10.
研究了热水浸提法从鱼废料中制备牛磺酸的最适条件,通过单因素实验和正交实验研究几种影响因素(浸提pH、水浴温度、水浴时间和液料比)对牛磺酸提取率的影响,分析探讨并确定了牛磺酸的最佳提取条件.结果表明:采用提取温度60℃、提取时间50 min、液料比6∶1、提取液pH值5.2的提取条件,从鱼废料中可以制备得到提取率高达27.93mg/g的牛磺酸,该结果明显高于其它方法.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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