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1.
山蜡梅叶中黄酮类化合物的提取效果与外界条件有关。通过单因素试验分析了提取液浓度、提取温度、提取时间及料液比等4个主要因素对提取率的影响。在单因素的基础上,通过正交试验,得到最佳提取工艺如下:超声波作用下,乙醇浓度为50%,料液比为1:40,提取温度为80℃,提取时间为3h。  相似文献   

2.
采用正交法研究了乙醇溶剂提取仙人掌中黄酮类物质的工艺条件.利用单因素试验,确定影响黄酮提取效果的4个因素:乙醇浓度、提取温度、提取时间和料液比的较优水平,用正交设计试验优化提取工艺条件.结果表明,最佳提取条件为乙醇浓度(V/V)90%、料液比20/1、温度55℃、时间1 h.  相似文献   

3.
选用乙醇作为提取溶剂,对高粱中总黄酮进行提取,研究乙醇浓度、浸提温度、浸提时间、料液比对高粱黄酮提取率的影响.并通过单因素及正交试验,确定了高粱黄酮的最佳提取工艺:乙醇浓度为65%,80℃下浸提2 h,料液比为6∶100.此工艺下提取的高粱黄酮含量为0.54%.  相似文献   

4.
探讨用醇提法提取竹叶中黄酮类成分的最佳工艺,为竹叶的开发利用提供理论依据。以竹叶为试材,以乙醇为溶剂,采用分光光度法对竹叶中的黄酮类化合物的含量进行测试。通过单因素实验研究乙醇浓度、料液比、提取温度、提取时间对总黄酮提取率的影响,再采用正交试验法优化提取总黄酮的最佳工艺条件。单因素实验和正交试验表明:影响黄酮提取率的因素主次顺序是:料液比〉乙醇浓度〉提取温度〉提取时间。最佳实验条件为料液比1:20,60%的乙醇,60℃提取4h,竹叶中黄酮的含量为7.88mg.g-1。  相似文献   

5.
本试验以干香菇为原料,针对香菇多糖提取工艺中提取时间、温度、料液比三个主要因素与香菇多糖提取量的关系分别进行单因素试验。通过试验得到了影响香菇多糖提取量的基本工艺条件:时间5小时左右,温度85℃左右,料液比1:30左右;同时对试验结果进行单因素方差分析,发现时间、温度、料液比对香菇多糖提取量均有显著影响;并通过做折线图直观地反映出了各因素与香菇多糖提取量的影响关系。  相似文献   

6.
本试验以干香菇为原料,针对香菇多糖提取工艺中提取时间、温度、料液比三个主要因素与香菇多糖提取量的关系分别进行单因素试验。通过试验得到了影响香菇多糖提取量的基本工艺条件:时间5小时左右,温度85℃左右,料液此1:30左右;同时对试验结果进行单因素方差分析,发现时间、温度、料液比对香菇多糖提取量均有显著影响;并通过做折线图直观地反映出了各因素与香菇多糖提取量的影响关系。  相似文献   

7.
目的:利用响应面优化龙胆草中龙胆苦苷的提取工艺.方法以龙胆草为原料,考察了乙醇浓度、提取时间、料液比及提取温度对龙胆草中龙胆苦苷提取率的影响,在单因素试验的基础上利用Design Expert数据处理软件进行响应面实验设计,确定龙胆草中龙胆苦苷的最佳提取工艺.结果及结论:在乙醇浓度为70%,提取时间为3h,提取温度71.5℃,料液比1:10时提取率最佳,龙胆苦苷提取率可达5.56%.  相似文献   

8.
为研究皱皮木瓜总酚酸的提取工艺,在单因素试验基础上,考察了料液比、乙醇浓度、提取温度、提取时间、提取次数等对皱皮木瓜总酚酸提取率的影响,以总酚酸含量为指标,结合正交试验优选了最佳提取条件.结果表明:4种影响提取率的因素依次为:提取温度>提取时间>料液比>乙醇浓度,提取温度对总酚酸提取影响较为明显.最佳提取工艺为:乙醇浓度体积比60%,提取温度90℃,料液比为1︰40(g·m L-1),提取5 h,1次.在最佳提取工艺下,皱皮木瓜总酚酸浸膏得率38.9%,总酚酸含量0.303 g·g~(-1),最后提取率为34.22%,此提取总酚酸工艺简便准确易行.  相似文献   

9.
通过超声波处理,采用单因素试验和正交试验,考察了超声功率、超声时间、料液比、浸提温度对油莎豆可溶性糖提取的影响,并根据单因素试验结果对油莎豆可溶性糖提取工艺进行了四因素三水平的正交优化.结果表明:四个因素对油莎豆可溶性糖提取的影响主次顺序为浸提温度料液比超声时间超声功率;最佳工艺条件为超声功率700 W,超声时间10min,料液比(g/mL)1∶50,浸提温度80℃.在此工艺条件下可溶性糖提取率为14.7%.  相似文献   

10.
甲醇浸提法提取荠菜黄酮工艺优化   总被引:1,自引:0,他引:1  
以荠菜为原料,研究了甲醇浓度、浸提温度、浸提时间、料液配比等单因素对荠菜中黄酮类化合物浸提效果的影响。在单因素试验的基础上,通过二次回归正交旋转试验得到了最佳提取工艺:甲醇体积分数为0.125,浸提时间为2.9 h,料液质量比为1∶32.7。在最佳浸提条件下得到荠菜黄酮类物质提取量为每克干样中芦丁当量29.33 mg。  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.
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   

16.
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   

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

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  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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