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1.
为了有效提高末水坛紫菜资源的利用率,以末水坛紫菜为原料,考察热水法和微波法提取坛紫菜多糖的多种影响因素.利用苯酚-硫酸法和3,5-二硝基水杨酸比色法(DNS法)测定多糖含量,单因素实验确定各因素的最适水平,L9(34)正交试验确定多糖提取工艺.结果表明,影响热水法制备紫菜多糖提取率的主要因素为浸提温度,其次为料液比和浸提时间;热水法制备末水紫菜多糖的最佳工艺为:浸提温度55℃、料液比1∶32(g∶m L)、浸提时间90 min;影响微波法制备紫菜多糖提取率的主要因素为:微波功率、料液比和微波时间,最佳工艺条件为:微波功率550 W、料液比为1∶43(g∶m L)、微波时间60 s.说明,热水法和微波法均可用于末水坛紫菜多糖的提取.  相似文献   

2.
响应面法优化微波辅助提取桑叶多糖的工艺研究   总被引:1,自引:1,他引:0  
利用微波辅助技术进行桑叶多糖提取,通过单因素实验确定因素与水平,应用Box-Behnken设计3因素3水平的试验,依据回归分析确定最优的提取工艺条件.结果表明,微波辅助提取桑叶多糖的优化提取工艺条件为:温度88℃、时间11 min和液固比18∶1,提取的多糖含量为15.20 mg/g.微波辅助提取的多糖含量分别比传统水提法提取10 min和60 min高2.18倍和0.23倍.  相似文献   

3.
以葡萄籽为材料,采用单因素和正交实验优化葡萄籽黄酮和多糖的微波辅助分步提取工艺。结果表明:黄酮提取的最佳条件:70%乙醇,料液比1:10(g/m L),微波功率100 W处理60 s,黄酮得率为57.73 mg/g;将提取黄酮后自然晾干的葡萄籽渣按料液比1:25(g/m L)加入水,微波功率150 W处理40 s,多糖得率为52.47 mg/g。优化后的微波辅助分步提取葡萄籽黄酮和多糖的方法,操作简单、快速、高效,提高了葡萄籽的附加值。  相似文献   

4.
为探明燕山板栗多糖的最佳提取工艺,采用单因素试验和正交试验确定了盐酸提取法和微波提取法提取板栗多糖的最佳条件,并采用苯酚-硫酸法和高效液相色谱法比较了两种提取方法在多糖得率和分子量分布上的差异。结果表明:盐酸提取法提取板栗多糖的最佳工艺为:盐酸浓度为0.72 mol/L,提取时间为40 min,提取温度为70℃,提取剂用量为20 m L/g,多糖得率为18.66%±2.54%;微波提取法提取板栗多糖的最佳提取工艺为:提取时间为50 s,微波强度为800 W/g,提取剂用量为30 m L/g,多糖得率为11.87%±0.87%;在最佳条件下盐酸提取法可显著提高板栗多糖得率,且分子量测定结果显示盐酸提取法对板栗多糖的降解作用小。因此,两种提取方法中,盐酸提取法是燕山板栗多糖提取工艺的较优方法。  相似文献   

5.
通过响应面分析法对微波辅助萃取仙鹤草多糖工艺进行优化,最终确定仙鹤草多糖的实验室最佳提取工艺条件为:微波功率400 W、微波时间111 s、提取温度87.3℃、液料比70.17 m L/g,且此条件下仙鹤草多糖提取率为4.54%.经验证性实验可知,此最佳提取工艺条件下的多糖提取率与响应面分析模型所得最优值有较好的拟合度,具有实际应用价值,且相对常规水煮法而言,微波辅助萃取法有提取时间短,提取温度低,提取率高等优点.  相似文献   

6.
为了探求微波法提取软枣猕猴桃干粉中多糖的最优工艺条件,在单因素试验的基础上,以料液比、提取时间、提取功率为自变量,多糖提取率为响应值,利用响应面法分析建立二次回归模型,并研究各因素及其交互作用对多糖提取率的影响.结果表明,微波法提取软枣猕猴桃干粉中多糖的最佳工艺条件为提取功率300 W,提取时间120 s,料液比1∶27(g/mL).在此条件下,软枣猕猴桃多糖提取率达到(17.83±0.49)%.  相似文献   

7.
以金线莲为原料、金线莲多糖提取率为指标,优化了超声波辅助提取金线莲多糖的最佳工艺条件.结果表明,在料液比(g∶m L)=1∶70、温度80℃、超声功率210 W的条件下作用50 min,金线莲多糖提取率达到2.495%.超声波技术强化了金线莲多糖的提取效果.  相似文献   

8.
本实验利用超声微波辅助热水浸提法提取扇贝瑶柱多糖,除蛋白后用所得多糖进行了免疫活性的研究,并探究扇贝多糖口服液的制备工艺.实验结果表明,扇贝多糖最佳提取工艺为微波功率650 W、微波提取时间15 min、温度50℃及液料比60∶1;细胞实验中扇贝多糖浓度在125-2000μg/mL范围内可以促进巨噬细胞RAW264.7吞噬中性红的能力,浓度在250-2000μg/mL范围内能促进巨噬细胞RAW264.7分泌NO且呈浓度依赖性;扇贝多糖口服液最佳调配配方为1.6%扇贝多糖、3%白砂糖、1%蜂蜜、0.07%柠檬酸.该制备工艺简单可靠,口服液品质尚佳.  相似文献   

9.
利用统计分析中的正交试验和方差分析,通过微波法确定中药大黄多糖的最佳提取条件,考虑的因素是微波功率、提取时间、提取次数、料液比和pH值。结果表明,大黄多糖微波提取的最佳工艺条件为:提取时间3 min,微波功率400 W,料液比1∶10,pH值为10。这种优化设计可以作为制定提取大黄多糖工艺的可靠依据。  相似文献   

10.
《贵州科学》2021,39(2)
目的:探讨不同提取方法对南沙参多糖的提取率影响,优化南沙参多糖提取工艺。方法:在单因素试验基础上,应用响应面法进一步优化南沙参多糖提取工艺。结果:优化的南沙参多糖提取条件提取火力(功率)为700 W、时长为85 min、料液比为1∶35(g/mL),此时微波法对南沙参多糖的提取率为10.50%,显著高于其他提取方法。结论:此方法提取南沙参多糖具有提取率高、工艺稳定、操作简便等优点。  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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