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1.
为研究膳食纤维制备工艺及物化特性,以独尾草(Eremurus chinensis Beib.)肉质根加工品(石参)为研究材料,通过单因素试验和响应面分析,确立了酸碱法制备石参膳食纤维的工艺条件。其优化后的基本工艺参数为原料颗粒直径0.3 mm,碱液浓度0.58 mol/L,碱液料液比1∶10,碱液浸提时间88.93 min,碱液浸提温度58.56℃,酸液浓度10%,酸液料液比1∶10,酸液浸提时间60 min和酸液浸提温度61.44℃;此条件下的理论得率为15.65%。  相似文献   

2.
【目的】研究碱法提取方格星虫体壁中水溶性方格星虫多糖的条件及优化。【方法】根据料液比、浸提时间、浸提温度、碱液浓度对多糖得率的影响,并通过正交试验得到方格星虫水溶性多糖浸提工艺优选因素组合。【结果】影响方格星虫多糖得率的因素主次顺序为浸提温度料液比浸提时间碱液浓度;最佳浸提条件为温度50℃,料液比1∶6g/mL,时间4h,碱液(NaOH)的质量分数为8%。【结论】最佳浸提工艺条件下多糖浸提提取率最大为1.81%。  相似文献   

3.
葡萄籽油的提取和精炼工艺研究   总被引:1,自引:0,他引:1  
对葡萄籽油提取和精炼工艺进行了研究.结果表明,在文中的试验条件下,葡萄籽油浸提最佳工艺条件是:石油醚为浸提剂,葡萄籽粒度60目、含水量7.0%、料液比1 g∶7 mL、温度70℃、浸提时间4h.葡萄籽油精炼工艺条件是:碱炼初温45℃,碱液浓度9.50%,超碱用量0.3%;水化加水量2%,水化时间分别为1.0、0.5 h;二次脱色工艺为活性脱色白土,加量第1次1%,脱色时间30 min、脱色温度80℃,第2次加量1%,脱色时间15 min,温度85℃,真空度0.08 MPa;在真空度0.08 MPa、温度180℃、脱臭时间1 h条件下可以脱除葡萄籽油中的臭味成分,保持葡萄籽的固有香味.  相似文献   

4.
葡萄籽蛋白提取工艺研究   总被引:1,自引:0,他引:1  
赵毅敏 《河南科学》2009,27(10):1229-1232
采用碱溶酸沉法对葡萄籽蛋白提取工艺进行了研究.结果表明:葡萄籽粉碎粒度为40目,以pH值为9的碱液,按m(料)∶V(液)=1∶10,在50℃条件下搅拌浸提45min时,蛋白质的提取最经济.  相似文献   

5.
采用单因子试验和L9(34)正交试验设计对丹参糖蛋白的水提醇沉工艺及一般理化性质进行了研究,试验了料液比、提取时间、提取温度和盐浓度对丹参水溶性糖蛋白提取的影响.结果表明,影响糖蛋白得率的主次因素为料液比、浸提温度、浸提时间、盐浓度,最佳提取工艺条件为料液比1∶20,提取温度70℃,提取时间4h,0.1 mol/L的NaCl,Savage法脱蛋白7次,80%乙醇醇析.在此最佳工艺条件下,糖蛋白得率为5.03%.理化性质研究结果表明,提取物是糖含量为26.24%、蛋白质含量为37.34%的高中分子量范围内的酸性糖蛋白.  相似文献   

6.
蚂蚁蛋白质提取方法的比较研究   总被引:1,自引:0,他引:1  
以铺道蚁(Tetramorium caespitum)为实验材料,采用正交试验法,对蚂蚁蛋白质的提取条件进行了研究.实验分别采用碱提蛋白法、盐提蛋白法、Tris-HCl缓冲液提蛋白法等3种提取方法.对其主要条件:不同浓度、浸提温度、浸提时间、固液比以及Tris-HCl液的pH值等进行了研究.结果表明,碱提蛋白法的最佳条件为:碱液浓度为1%,固液比为1∶15,浸提时间为60 min,浸提温度为80℃;盐提蛋白法的最佳条件为:盐液浓度为1.5%,固液比为1∶15,浸提时间为60 min,浸提温度为50℃;Tris-HCl缓冲液提蛋白法的最佳条件为:pH值为8.3,固液比为1∶15,浸提时间为90 min,浸提温度为20℃.在这3种方法中,碱提蛋白法的蛋白质得率最高,其次为盐提蛋白法,而Tris-HCl缓冲液提蛋白法最低.  相似文献   

7.
采用碱提酸沉法提取补骨脂蛋白质,以二喹啉甲酸(BCA)法测定的蛋白质溶出率为指标,通过单因素实验和正交实验优化补骨脂蛋白质的碱提工艺条件,考察浸提p H、料液比、温度、时间等因素对补骨脂蛋白质提取的影响.结果表明,四种提取因素的影响从大到小的顺序为:浸提p H料液比温度时间.最佳工艺条件为浸提p H 10.0、料液比(g/m L)1∶20、温度45℃、浸提时间150 min,此条件下补骨脂蛋白质溶出率为23.69%.以BCA法测定酸沉蛋白质浓度,确定补骨脂蛋白质的最大沉淀量p H为4.5,蛋白质的最大沉淀率为55.16%.对比发现理论提取率与实际提取率基本相同,证明BCA法测定补骨脂蛋白质的方法准确、可靠,为补骨质蛋白质的进一步研究利用奠定了基础.  相似文献   

8.
通过选取福建黄花梨皮为原材料,采用超声波辅助碱提取的方法提取福建黄花梨皮中的多糖,运用苯酚-硫酸法测定其多糖含量。首先通过单因素试验,研究各单因素:超声波提取温度、超声波处理时间、氢氧化钠碱液浓度、料液比对多糖提取率的影响,再利用L_9(3~4)进行正交设计试验。研究结果表明,福建黄花梨皮中多糖提取的最优工艺参数:超声波提取温度为45℃,超声波处理时间为60 min,氢氧化钠浓度0. 2 mol/L,料液比1∶40,在此条件下多糖的提取率可以达到57. 76%。  相似文献   

9.
对浒苔多糖的碱法提取工艺进行研究,为评价提取条件对浒苔多糖提取率的影响,首先选用固液比、浸提温度、浸提时间和碱溶液浓度4个因素进行单因素多水平实验,在此基础上进行正交试验,筛选出最佳提取工艺条件.实验结果表明,影响浒苔多糖提取率的各因素的主次关系依次为:浸提温度、浸提时间、固液比,碱溶液浓度;浒苔多糖碱法提取的最佳工艺条件为:提取温度90℃,提取时间2.5h,固液比1:40(g:mL),氢氧化钠溶液浓度0.3mol/L;最佳工艺条件下,浒苔多糖的提取率为3.1%.  相似文献   

10.
本文以柚叶为原料,研究从柚叶中提取多酚的工艺,利用单因素和响应面试验对提取工艺中影响柚叶多酚提取率的工艺参数(乙醇浓度、浸提时间、液料比、提取温度)进行了分析与优化.结果表明,柚叶多酚的最佳工艺条件为:乙醇浓度60%、浸提时间100 min、液料比20 m L·g-1、提取温度70℃,柚叶多酚提取率为22.76 mg·g-1,与模型预测值(22.88 mg·g-1)相比,其相对误差为0.52%,验证了该模型的有效性和实用性.  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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