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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.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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