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1.
本文研究了酸枣的间歇浸取、半连续逆流浸取、连续逆流浸取工艺,提出了最佳浸取条件。在浸取温度为55℃,水枣比为3.8时,连续逆流浸取工艺浸取率达到92%,浸汁浓度为14°Brix。并用浸取能力值对这三种工艺进行了评价。  相似文献   

2.
麻黄草常压浸取麻黄碱工艺研究   总被引:1,自引:0,他引:1  
采用常压三级循环逆流浸取法,从麻黄草提取麻黄碱,草水含碱量可以接近或达到日前工业生产上采用的加压浸取法的效果。  相似文献   

3.
采用均匀设计理论,对影响聚合硫浸取效率的浸取温度、液固比及浸取时间等因素进行了研究,探讨了灰色理论在均匀设计试验影响因素分析中的应用。结果表明,采用均匀设计和灰色理论来研究浸取分离的影响因素并确定优化浸取条件的方法是行之有效的。  相似文献   

4.
红茶连续逆流浸取工艺研究   总被引:6,自引:0,他引:6  
针对间歇法提取红茶的效率低、浓度低、利用率差的问题,采用L型螺旋式连续浸取器对红茶连续逆流浸取工艺进行了实验研究,根据对实验结果分析,在浸汁浓度、浸取率和浸取效率(浸取能力值F.E.A)等方面进行分析比较,并与两浸法浸取工艺相对比,得到了最优的浸取条件。浸取温度为85~95℃,浸取时间为33min,水茶比为8.2时,浸汁浓度为0.046kg/L,浸取率为78.4%,F.E.A为0.99g/L·min。  相似文献   

5.
改进茶叶中提取咖啡因的有效方法   总被引:6,自引:0,他引:6  
针对提取咖啡因常用的5种方法:"茶叶中加入生石灰在索氏提取器中用95%乙醇提取-升华法"、"茶叶中加入生石灰95%乙醇回流浸取-升华法"、"将茶叶在热水溶解浸取-氯仿萃取法"、"碳酸钠水溶液热浸取二氯甲烷萃取法"、"直接升华法",作者对提取咖啡因方法进行了实际比较,发现在茶叶末中混合一定量的碱碳酸钠,会改善咖啡因的收率,增强提取效果.  相似文献   

6.
本文阐述了硫酸直接浸取含钒灰渣提钒工艺中,硫酸浸取,浸出液中提取铵明矾、再提取中间盐并溶解之,溶剂萃取、反萃及沉钒的有关因素。并确定了最佳工艺条件。  相似文献   

7.
对绿茶连续逆流浸取的动力学问题进行了研究。用L型螺旋式连续逆流浸取器浸取绿茶时,浸取温度和水茶比对沿浸取器长度与浸汁浓度之间的相互关系有显著影响,但随浸取温度的升高,影响程度减弱,而浸取时间的影响不显著。获得的线性回归方程对该浸取器的设计很有价值。  相似文献   

8.
南方重稀土矿浸取动力学分析   总被引:2,自引:0,他引:2  
田君  尹敬群 《江西科学》1996,14(2):81-86
探讨了浸取反应温度、浸取剂初始浓度,矿石粒度及搅拌强度对浸取速率的影响,并进行了浸取动力学分析。结果显示,其浸取过程可用收缩未反应芯模型表达,属内扩散控制,求出了表观活化能,导出了动力学方程,为高效,低耗合理地开采南方重稀土提供了科学的途径和理论依据。  相似文献   

9.
对反应堆退役固体废物中的水池底泥和锈垢进行浸取研究,研究了α核素的浸取方法、浸取剂、浸取时间、浸取体积比等因素对浸取率的影响。实验结果表明:淋洗法以HNO3-NaNO3为淋洗剂,溶浸法以7.5mol/L HNO3为浸取剂、固液比为6:1、浸取时间40min时,均取得97%以上的浸取率。  相似文献   

10.
本文采用正交法,研究了硫酸浸取锌灰中锌、镉的最优条件组合以及浸取液中置换出海绵镉的条件。得到锌浸取率为100.1%,镉浸取率为99.8%。浸取的最优条件为:硫酸用量为理论量的130%,硫酸:水(体积比)为1:6,反应时间7小时。由浸取液中制得海绵镉中镉含量达70.97%。镉回收率为89.50%。  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.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

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