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1.
亚硫酸盐废液戊糖,己糖同步酒精发酵的调控   总被引:5,自引:0,他引:5  
休哈塔假丝酵母R(CandidashehataeR)用于亚硫酸盐制浆废液戊糖、己糖同步酒精发酵时,发酵液pH值呈规律性变化。引起pH值变化的原因是发酵过程中酸性非糖还原物被代谢及废液中存在醋酸。废液中已糖对戊糖代谢的抑制可通过调节空气量来解决。还研究了亚硫酸盐制浆废液适宜的发酵条件,在发酵初始pH5.0~5.5,温度38±1℃,溶解氧浓度0.9~1.0mg·L ̄-1的条件下对固形物为19.94%的亚硫酸盐制浆废液发酵34h,废液中戊糖、己糖能同步被酵母利用,糖的利用率为89.9%,平均每克糖产酒精0.40g,是理论得率的83.1%。  相似文献   

2.
灵芝深层培养工艺的研究   总被引:3,自引:0,他引:3  
为了提高发酵终了时灵芝菌丝浓度以获取高等真菌多糖,对灵芝AS.5.65的深层培养工艺进行了研究。确定了最适发酵条件为:5%玉米淀粉、0.3%玉米浆、1%豆饼粉、0.6%糖蜜、0.15%KH2PO4、0.075%MgSO4·7H2O,pH5.5~6.0,温度28℃,摇床转速150r/min,摇瓶种子培养3d接种。接种量5%、装液量50mL,培养5~6d可终止发酵。最终菌体干重可达27.5g/L、含粗多糖2.6g/L。  相似文献   

3.
番茄汁乳酸菌发酵饮料的研制   总被引:9,自引:0,他引:9  
以番茄为原料,经乳酸菌发酵而制成番茄汁乳酸菌发酵饮料,通过对接种量、发酵时间、发酵温度、风味、稳定性进行实验,从而确定出最佳工艺参数为:接种量5%,发酵温度40℃,发酵时间30h,黄原胶0.03%,耐酸性CMC-Na0.02%。  相似文献   

4.
真菌转化菊糖生产低聚果糖的研究   总被引:2,自引:0,他引:2  
研究了真菌黑曲霉(Aspergillus niger)A97转化菊糖生产果糖的适当条件,结果表明:发酵初始pH为5.5 ̄6.0,菊糖浓度为2%,接种量5%,控制前期发酵温度为28 ̄33℃,36h后发酵温度为32 ̄33℃,发酵周期为42h左右,最高产酶达254.7μ/ml,在10L自控发酵罐中,产酶达到同样水平。产品总还原糖含量68%,其中果糖95%,葡萄糖5%。  相似文献   

5.
通过对啤酒酵母富铬发酵条件(发酵培养基配方,发酵时间,发酵温度,接种量,培养基装量)的探讨,得到了富铬啤酒酵母发酵的最佳工艺条件,即:(1)发酵培养基配方:葡萄糖1%、酵母膏0.3%、蛋白胨1.05%、KH2PO40.1%、MgSO47H2O0.1%、(NH4)2SO40.1%、Cr3+浓度0.02g/L、pH值5.1;(2)最佳吸收时间:发酵48h.(3)发酵温度:28℃;(4)接种量:10%;(5)培养基装量:50mL.  相似文献   

6.
本文报道了采用硝酸氧化工艺生产对硝基苯甲酸的小试,研究了反应物用量、反应温度和压力等工艺条件。采用间歇式操作,最佳反应条件为对硝基甲苯与硝酸的摩尔比在1:2.2~1:4.0,硝酸浓度在20%~45%,反应温度在150~220℃,反应压力在1~4MPa,反应时间0.5~2h产率高达95%以上  相似文献   

7.
绿色木霉固态发酵产纤维素酶条件及酶性质的研究   总被引:4,自引:0,他引:4  
对绿色木霉 Trichoderma viride9405固态发酵产纤维素酶的条件及酶的性质进行了研究。结果表明,最适产酶条件为:秸秆粉与麸皮的比 7:3;玉米秸秆粉培养基含水量250%;花生皮粉培养基含水量150%;pH4.0~4.5;温度30℃;周期72h。在玉米秸秆粉固体培养基上,所产纤维素酶CMC活力为1386u/g,FPA活力为217u/g,棉花糖化力为325u/g。必作用的最适条件为pH4. 5~5. 0,温度 50℃;在 45℃以下, pH3. 5~6. 0之间比较稳定,室温放置半年,酶活保存率在90%以上。  相似文献   

8.
用5%麦粉的α-淀粉酶水解液培养麦角菌ATCC20019,结果其发酵液能产生麦角隐亭(50.16±2.40)μg/mL,与30%蔗糖的发酵培养基的产碱量(20.74±3.53)μg/mL相比,两者有差异(p<0.05).在10%蔗糖的培养基中,发酵第4天后补加5%麦粉的α-淀粉酶水解液,麦角隐亭的产量为(47.12±6.34)μg/mL,也高于碳源为30%蔗糖的产碱量(19.89±2.40)μg/mL,两者差异显著,p<0.01.而两种方法的菌丝体生长量均相差无几,p>0.05.  相似文献   

9.
固定化酵母发酵海藻酒的研究   总被引:1,自引:1,他引:1  
对游离细胞与固定化细胞的分批发酵动力学进行了研究并建立了相应的发酵动力学方程。在小型玻璃柱式反应器中进行连续发酵海藻酒的研究,确定了适宜的发酵工艺为:发酵温度18-20℃,固定化细胞凝胶珠充填系数0.5,稀释速率0.1h^-1,发酵时间由游离细胞发酵7天缩短到0.5天左右。建立了柱式反应器固定化酵母第藻酒连续发酵的数学模型。  相似文献   

10.
野油菜黄单胞菌X.c—18的选育及发酵条件的研究   总被引:2,自引:0,他引:2  
黄筱萍  刘兰 《江西科学》1997,15(1):13-20
通过人工诱变野油菜黄单胞菌,筛选出1株具有良好抗变异性的突变株X.c-18。该突变株能很好地利用蔗糖和玉米淀粉为碳源,蛋白胨和黄豆饼粉为氮源。其最佳黄原胶发酵总糖量与总蛋白质量之比为5:0.5,最适pH值为7.0,温度为28℃。摇瓶发酵72y,黄原胶产量每升发酵液一般可在30g以上,最高产量达32.6g,对碳源转化率为71.54%。  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 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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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