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1.
刘仲敏  常琴 《河南科学》1992,10(2):187-191
利用固定化酵母用于传统啤酒发酵,结果表明:酵母在固定化载体中生长良好、增殖快、稳定性高,可使啤酒的主发酵期由7~12天缩短为36小时,有效的提高了设备利用率,啤酒产量增加30~40%.同时还节省能源,降低成本.  相似文献   

2.
研究表明,玉米生料酒精发酵的淀粉利用率达到88%,原料出酒率达到36%.与传统的高温高压蒸煮工艺相比,新工艺可节省约30%的能耗.  相似文献   

3.
固定化Zymomonas mobilis 10225乙醇发酵研究   总被引:3,自引:0,他引:3  
运动发酵单胞菌(Zymomonas mobilis10225)为乙醇发酵菌种.在葡萄糖浓度为10%(w/V)的发酵培养基中,分别进行游离细胞,固定化细胞的乙醇发酵实验.结果表明,游离细胞乙醇发酵的产率系数为0.42,达到了理论值的82.4%,而固定化细胞乙醇发酵产率系数为0.51,达到了理论产率的100%.固定化技术对于提高运动发酵单胞菌酒精发酵表现有显著作用.  相似文献   

4.
高活力碱性蛋白酶产生菌的选育与发酵放大   总被引:1,自引:0,他引:1  
为了选育高活力碱性蛋白酶产生菌株.采用复合诱变(紫外照射、NTG、离子注入)方法,结合平板初筛与摇瓶复筛.获得一株高产突变株HAPN-169,其酶活力为3.5×10 u/mL.高产菌株HAPN-169根据气液接触中体积传氧系数kLa相同的原则发酵放大(7L,30L,200L),其发酵参数为:温度34℃,装液系数0.7,接种量5%,使溶氧维持在20~30%,控制发酵过程pH不低于7.0.在7L发酵罐,发酵时间为54小时,酶活力为3.6×104u/mL;在30L发酵罐,发酵时间为50小时,酶活力为3.86×104u/mL;在200L发酵罐,发酵时间为36小时,酶活力为4.2×104u/mL.发酵液pH在7.5左右时,酶活力在峰值,发酵终点一到,必须马上下罐.该结果对为我围碱性蛋白酶工业发展提供一定的基础.  相似文献   

5.
龙葵果醋发酵工艺的研究   总被引:1,自引:0,他引:1  
研究了以龙葵为原料,采用酵母菌和醋酸菌连续液态发酵生产龙葵果醋的发酵工艺.选择发酵温度为32℃,装样量为40%,接种量为20%的条件,可得到澄清的发酵果醋,陈酿后品质更佳.  相似文献   

6.
上面发酵和下面发酵小麦啤酒发酵过程的差别研究   总被引:1,自引:0,他引:1  
为了比较上面发酵型和下面发酵型小麦啤酒发酵过程的变化差别,在100L啤酒设备上对两种啤酒发酵过程中影响啤酒品质的各个理化指标进行了跟踪比较研究.结果表明:在整个发酵过程中,上面发酵法的总酸含量和双乙酰峰值高于下面发酵法;α-氨基氮含量和pH值总体低于下面发酵法;两种发酵工艺的酒精度以及糖度值的差别较小,所有指标的测定值都在正常范围之内.  相似文献   

7.
对黑曲霉HYA4固态发酵生产果胶酶的培养条件进行了研究,固态发酵培养基组分为:250 mL三角瓶中甜菜渣5 g,黄豆粉5 g,NH4H2PO4 0.4%,FeSO4·7H2O 0.05%.料水比1:2.采用此优化的培养基在培养温度36℃和初始pH自然条件下进行发酵,果胶酶酶活力可达5465.8 U/g(干曲).  相似文献   

8.
该研究对实验室保存的4株运动发酵单胞菌(Zymomonas mobilis CICC10225, ATCC29191, CICC10232, IFFI10225)在不同葡萄糖浓度的合成发酵培养基及甘薯糖化液发酵培养基中的乙醇发酵能力进行比较,然后以筛选出的乙醇发酵效率最高的Z.mobilis CICC10225 为出发菌株,进行了较深入的以甘薯为原料的乙醇发酵研究,结果显示:Z.mobilis CICC10225具有快速代谢底物生产乙醇的能力,游离细胞乙醇发酵时,最高乙醇浓度达79.8 g/L,  相似文献   

9.
采用玉米秸秆为原料,先氢氧化钠进行预处理后,再加入纤维素酶与酵母进行乙醇发酵。首先通过单因素试验,确定了酵母菌接种量、发酵时间、发酵温度、发酵p H四因素对乙醇的最佳影响程度。再采用四因素三水平的正交实验确定发酵的最佳组合条件。结果表明,乙醇发酵最佳工艺条件为酵母接种量6环、发酵时间36 h、温度38℃、p H=4.8,此时乙醇浓度值为12.5432 mg/m L。  相似文献   

10.
恒温发酵与变温发酵柠檬酸过程及其比较   总被引:2,自引:0,他引:2  
以纤维素水解液为原料,利用黑曲霉发酵柠檬酸。研究了恒温发酵和变温发酵过程,并对二者发酵柠檬酸的产量进行了比较。结果表明:恒温发酵在8h~104h为主要产酸期,在l0h时,产酸量最大;变温发酵可刺激菌体生长,产酸量随时间的增加而增加,与恒温发酵相比,变温发酵初期的产酸量较高,之后,产酸量降低。但变温发酵最终菌体的量要高于恒温发酵。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

19.
20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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