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1.
发酵法生产味精工艺中 ,提取味精后的废液内含有大量的谷氨酸菌体蛋白 ,对其絮凝过滤机理进行了研究 ,采用高分子化合物作为絮凝剂 ,用絮凝过滤方法分离提取谷氨酸菌体蛋白 .该方法操作简单、菌体得率高  相似文献   

2.
苜蓿叶蛋白提取工艺的优化研究   总被引:7,自引:1,他引:6  
本文应用直接加热法、酸碱化加热法和酸碱法对苜蓿叶蛋白的提取方法进行了比较研究,同时对叶蛋白提取的工艺参数进行了优化试验。结果表明在苜蓿叶蛋白最佳的提取方法为直接加热法,最佳工艺参数为料水比1:3,滤布层数为2层,过滤后于85℃水浴中,恒温7min。在最佳工艺条件下,苜蓿叶蛋白得率可达4.70%。  相似文献   

3.
葎草叶蛋白提取工艺的优化   总被引:9,自引:0,他引:9  
对配合使用酸法、碱法以及加热法提取葎草叶蛋白的工艺及工艺条件进行了初步的研究,以提高其蛋白质含量。分别进行了浸提剂pH值、料液比、打浆时间、浸提时间、汁液pH值和絮凝温度对蛋白质影响的单因素实验研究,结果表明,葎草叶蛋白的最佳提取工艺条件:常温下料液比1:5,打浆时间3min,浸提时间3min,浸提剂的pH值为6~8;葎草叶蛋白的分离条件为70℃时,沉淀分离得到叶绿体叶蛋白,调pH值为10时分离出细胞质叶蛋白Ⅰ,调pH值为2时分离出细胞质叶蛋白Ⅱ;葎草叶蛋白产品在60—80℃条件下干燥。采用此工艺提取葎草叶蛋白的得率为4.62%。  相似文献   

4.
研究蛋糕粉中添加的无铝复合膨松剂,首先通过单因素实验确定了碳酸氢钠、柠檬酸、酒石酸氢钾、葡萄糖酸内酯的添加范围分别为26%~28%、5%~10%、18%~23%、12%~17%,再通过正交实验对配方进行优化,最终确定蛋糕粉中无铝复合膨松剂各组分的最佳添加量为碳酸氢钠28%、葡萄糖酸内酯15%、酒石酸氢钾23%、柠檬酸10%、食盐15%、淀粉9%.在最佳配方下进行验证实验,蛋糕品质感官评分为92.5.  相似文献   

5.
运用正交旋转组合设计的方法研究了谷氨酰胺转氨酶活性、反应温度和反应时间对豆浆凝固的影响,并利用得到的最佳组合与葡萄糖酸-γ-内酯分别对豆浆进行凝固实验,比较两者的凝胶性和抗压能力.结果表明:MTG酶活性、反应时间和反应温度对豆浆凝固影响较大,当酶活力为0.04~O.64 u/mL,35 ~50℃作用170~310min均可使豆浆凝固,其中又以酶活0.32 u/mL、45℃作用300 min效果为最佳,此时豆腐凝固体积比为76.92%,高度比为73.98%,分别比葡萄糖酸-γ-内酯豆腐高10.25%和4.82%.  相似文献   

6.
为探讨合成环十五内酯的新工艺,以蒜头果油为原料制备15-羟基十五烷酸酯,在强酸性阳离子交换树脂催化下合成环十五内酯.比较了两条合成路线:蒜头果油经提取得到二十四碳-15-烯酸,经臭氧化、还原、甲酯化反应得到15-羟基十五烷酸甲酯,在强酸性阳离子交换树脂催化下发生内酯化反应生成环十五内酯,收率为14.4%;蒜头果油直接经臭氧化、还原、甲酯化反应后,在强酸性阳离子交换树脂催化下发生内酯化反应生成环十五内酯,收率为10.4%.考察了树脂类型以及不同酯基的15-羟基十五烷酸酯对内酯化反应的影响,结果表明LS-50树脂的催化效果最佳,15-羟基十五烷酸乙酯合成环十五内酯的收率达到19.5%.  相似文献   

7.
从土壤和污泥中筛选出的混合菌群,在葡萄糖肉汤培养基和硅酸盐细菌培养基中培养,并用分光光度法测定混合菌群对Cr3 的絮凝效果.实验结果表明:2种培养基中混合菌群的代谢物对废液中的Cr3 均有絮凝作用;葡萄糖肉汤培养基培养的混合菌群在16h内达到生长峰值,pH4.0,对Cr3 的絮凝率达71.42%;硅酸盐细菌培养基培养的混合菌群到达生长峰值所需时间为30h,pH5.23,对Cr3 的絮凝率达93.51%;最适絮凝温度为30℃.  相似文献   

8.
从活性污泥中筛选出1株高效微生物絮凝剂产生菌BJ-I,其絮凝率达87.6%.通过生理生化分析及16S rDNA序列鉴定该菌株为短芽孢杆菌(Bacillus brevis).该菌产絮凝剂的最适碳源和氮源分别为20 g/L的葡萄糖和2.0 g/L的蛋白胨;适宜的初始pH和培养温度分别为7.0和30℃;在培养基中添加0.5 g/L的Mg2+有利于菌体生长,但对絮凝荆合成无影响.对该絮凝剂的特性研究结果表明:菌液投放量3%、pH值在5~9、温度为60 ℃条件下絮凝效果最好,加入浓度为8%的Ca2+可显著提高其絮凝活性.实验证明,该菌起絮凝作用的物质存在于发酵液中,主要成分为杂多糖.  相似文献   

9.
为提高小球藻培养的经济效益和高效资源化综合利用水葫芦,初步研究了水葫芦提取植物蛋白废液对小球藻生长、叶绿素和蛋白质含量的影响。研究结果表明,光照条件下,培养藻液中添加不超过6%体积的水葫芦废液,小球藻的生长速度及藻体叶绿素和蛋白质含量均随废液添加量的增加而提高,即使培养藻液中不添加任何营养元素而只添加1%~6%体积的废液,小球藻的生长速度及藻体叶绿素和蛋白质含量即可达到和超过基础营养液培养组的小球藻,说明水葫芦提取植物蛋白的废液可极大地提高小球藻培养的经济效益,甚至可完全替代营养盐的添加;但在无光条件下,添加废液对小球藻生长无效,说明未经处理的水葫芦废液尚不能作为小球藻异养培养的营养源。  相似文献   

10.
以采自昆明滇池的新鲜水葫芦为材料,以酸降解液中所含还原糖和挥发性脂肪酸的含量为指标,研究温度、酸质量分数、固液比和处理时间对稀盐酸降解新鲜水葫芦有机质的影响.结果表明,各因素对还原糖含量的影响顺序为:温度酸质量分数固液比处理时间;对挥发性脂肪酸含量的影响顺序为:酸质量分数固液比处理时间温度.同时确定了稀盐酸预处理水葫芦的最佳条件为:酸质量分数7%,处理温度60 ℃,固液比1 g:3 mL,处理时间1.5 h,在此条件下还原糖和挥发性脂肪酸转化率达到4.4%和29.0%,与未处理样相比分别提高了628%和491%.可见,以此方式可提高水葫芦的生物利用率.  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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