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1.
产纤维素酶粗糙脉孢菌1602产酶条件优化   总被引:4,自引:0,他引:4  
通过优化设计,确定纤维素高产菌株Neurospora crassa 1602摇瓶发酵最佳产酶条件为:培养液初始pH值为5、5,培养温度为28℃,摇瓶转速为150rpm,培养96h;3%玉米芯粉、0.5%麸皮酸水解液(0.6mol/L)能够促进产酶,最适宜的有机氮源为黄豆粉;最适宜的无机氮源为NH4HSO4.在最适发酵条件下,其纤维酶的活力CMCase为10.34IU/ml.FPase为0.71IU/ml.  相似文献   

2.
通过枝动菌和罗思氏菌生化性质的初步研究,发现枝动菌在代谢过程中产生过氧化氢酶、色氨酸酶、氧化酶,V.P实验阳性,耐盐性小于3.5%,其最佳培养条件32°C,pH8.2,培养15h,葡萄糖为最佳碳源,酵母浸膏粉为最佳氮源。罗思氏菌产生蛋白酶、色氨酸酶,V.P实验阴性,耐盐性小于10%,其最佳培养条件28°C,pH9.2,培养35h,甘露醇和蛋白胨分别为最佳碳源和氮源。  相似文献   

3.
小米乳酸饮料的研制   总被引:2,自引:0,他引:2  
本文以小米、牛乳为原料,采用酶法糖化水解淀粉.经嗜热链球菌和保加利亚乳杆菌(1∶1)的混合菌种发酵而制得一种营养丰富,酸甜适口、香气浓郁的保健饮料。结果表明:小米浆糊化的最佳条件为8倍加水量,糊化温度为95—100℃。小米浆在PH5~6,温度在85℃下加入80单位/g干淀粉的糖化酶,酶解6h后,还原糖得率最高。小米乳酸菌饮料的最佳配方为5%牛乳、5%蔗糖、0.4%的复合稳定剂,混合菌种的接入量为4%。  相似文献   

4.
絮凝剂产生菌HYY-7的培养条件   总被引:4,自引:0,他引:4  
从生活污水厂的活性污泥中筛选出一株高效微生物絮凝剂产生菌,鉴定为青霉,命名为 ,其产生的微生物絮凝剂命名为MBF7。该茵产生微生物絮凝剂的最佳培养基为葡萄糖培养基,适宜的培养条件为:葡萄糖培养基初始pH值为4.5~6.0,培养温度为30℃;振荡箱的转速为200r/min,培养时间为3~4d。产生的高效絮凝剂MBF7具有良好的絮凝效果,对于实际排放的染料废水、餐厅废水和生活污水浊度去除率分别为92.5%,96.8%,90.2%。  相似文献   

5.
新疆哈密瓜蔓枯病菌的生物学特性及其室内药剂筛选试验   总被引:6,自引:0,他引:6  
本试验研究证明,新疆哈密瓜蔓枯病菌在pH4~10均可生长,以pH5~8之间生长最佳;其菌丝生长温度为10~34℃,最适生长温度为25~28℃;在供试培养基中以PDA、PSA和菜豆培养基上生长良好;供试的不同温度、培养基及不同酸碱环境均未见有分生孢子器和假囊壳产生。用生长速率法测定了12种药剂对瓜类蔓枯菌的抑制作用,结果以25%卡菌丹、40%除病灵、70%甲基托布津抑菌效果最为明显,在200~1000mg.kg^-1范围内抑菌率均为100%,50%金雷多米尔.锰锌和10%世高也表现出良好的抑菌效果。  相似文献   

6.
从活性污泥中分离筛选出3株对高岭土悬浊液具有较好絮凝作用的絮凝剂产生菌,通过对培养基初始pH和培养时间的优化及对采油废水絮凝处理效果的研究以了解其絮凝性能.结果表明:在培养基初始pH接近中性(pH6.0-7.0),培养时间为12~24h条件下,3种菌株对高岭土悬浊液的絮凝效果最佳,最大絮凝率达91.5%;3种菌株对采油废水具有一定的处理效果,其絮凝率为30%~40%,CODcr去除率可达40%.  相似文献   

7.
地衣芽孢杆菌A.4041(Bacillus,licheniformisA.4041)耐高温α-淀粉酶,经硫铁沉淀和垂直板制备凝胶电泳纯化,得到三种电泳均一的组分,α-Ⅰ,α-Ⅱ和α-Ⅲ.其相对质量分数分别为14.7%,32.2%和52.9%;等电点为5.2,5.4和5.5;相对分子质量为48000,55000和60000.酶作用于可溶性淀粉的米氏常数分别为4.5mg/mL,3.4mg/mL和2.6mg/mL.最适作用温度皆为90℃;最适pH为6.0~6.5;稳定pH范围皆为4~11.5在温度高于70℃,保温30min条件下,三组分的活力开始下降,但α-Ⅱ和α-Ⅲ在100℃,保温30min时仍分别保持15%和20%的残余活力,表明该酶的热稳定性良好.Ca2+,Mg2+,K+对酶明显激活;Cu2+,Fe3+,Zn2+,Al3+,EDTA、甲醛、戊二醛对酶强烈抑制.  相似文献   

8.
产生淀粉糖化酶菌株的分离以及酶性质的初步研究   总被引:1,自引:0,他引:1  
从霉变物、土壤、醋曲、醋醅等分离出四株产生淀粉糖化酶且酶活较高的菌株,选取酶活最高的菌株vin-1作为出发菌株,初步鉴定为Aspergillus niger,其生淀粉糖化酶活力达到342U/g(干曲),酶最适作用温度为55℃,酶在pH值3.5~4.5之间有较高的酶活,最适pH值为4.0,Ca~(2+)、Mg~(2+)对酶有一定的激活作用,而Fe~(2+)、K~+、Fe~(3+)、Cu~(2+)、Mn~(2+)都有较强的抑制作用,Mn~(2+)抑制作用最大,达到近50%。  相似文献   

9.
以1%壳聚糖与5%戊二醛交联8h制得交联壳聚糖载体,1g载体固定10mg的果胶酶,载体先与酶液缓慢振荡混合30min后,在固定化体系(pH3.4,4℃)中固定反应12h,该条件下制得的固定化酶强度大韧性好。酶活力回收率高达56.31%;固定化酶的最适温度50℃,最适pH3.4,Km^app值为5.42mg·mL^-1,连续使用7次后,酶活力还保留70.45%以上,具有较好的操作稳定性。  相似文献   

10.
海藻酸钠-壳聚糖固定化漆酶的研究   总被引:5,自引:0,他引:5  
采用海藻酸钠包埋法和海藻酸钠-壳聚糖包埋-交联法固定化漆酶,探讨了固定化条件、固定化漆酶及游离酶的酶学性质,结果表明:包埋法和包埋-交联法固定化漆酶的最佳条件分别为海藻酸钠浓度3%、CaCl2浓度1.5%和海藻酸钠浓度2%、CaCl2浓度2%、壳聚糖浓度1.5%、戊二醛浓度1%.两种固定化漆酶的最适pH和最适温度相同,分别为5.0和30℃,游离酶pH为4.6,温度20℃.包埋法固定化漆酶、包埋一交联法固定化漆酶和游离酶的米氏常数分别为3.3,2.8,1.22mmol/L.  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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