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1.
不同生态因子对蛹虫草菌丝生长影响的研究   总被引:2,自引:0,他引:2  
本文主要针对蛹虫草菌丝生长对营养元素需求和对生态因子的要求进行试验研究。结果表明:蛹虫草菌丝生长的适宜碳源是葡萄糖,适宜氮源是蛋白胨,适宜C:N为40:1.适宜无机盐是KH2PO4,最适宜温度是20℃,最适宜含水量是70%,最适宜pH值是6.5。  相似文献   

2.
从固体培养基、液体培养基、碳源、氪源、酸碱度、温度、光照等方面探讨羊肚菌菌丝的生物学特性.结果表明,羊肚茵菌丝适宜在PDA固体培养基以及黄豆芽——玉米粉液体培养基中生长;单肚菌菌丝生长的最适碳源为葡萄糖,最适氮源为硫酸铵;羊肚菌菌丝生长的最适pH范围为6~7,最适温度为25~33℃之间,并且在光照条件为弱光时羊肚菌菌丝生长状况较好.  相似文献   

3.
蛹虫草菌丝体液体培养条件研究   总被引:4,自引:0,他引:4  
朱姣  王德源  任燕 《山东科学》2007,20(3):45-48
研究蛹虫草液体发酵条件,以干菌体得率为指标,通过单因素试验确定适宜的碳源、氮源、培养温度和pH值。结果表明,最适液体培养基为:葡萄糖20 g/L,蛋白胨5.0 g/L,最适pH=6.0,最适培养温度24℃。  相似文献   

4.
杏鲍菇菌丝生长条件的研究   总被引:5,自引:0,他引:5  
研究了碳源、氮源、温度和酸碱度对杏鲍菇菌丝生长的影响.结果表明:玉米粉是最佳的碳源,蛋白胨是最适的氮源,菌丝对有机氮的利用明显好于无机氮,在尿素培养基上不生长.最适生长温度为25℃,最适pH值为5.5-6.5.正交试验确定了最佳组合培养基:2%玉米粉,1%蛋白胨,0.3%磷酸二氧钾,0.05%硫酸镁。  相似文献   

5.
通过对蛹虫草(Cordyceps militaris)液体发酵产胞外多糖和菌丝虫草素的初步实验研究,获得了蛹虫草液体发酵联产胞外多糖和菌丝虫草素的适宜参数.研究结果表明,蛹虫草液体发酵联产胞外多糖和菌丝虫草素的较适宜的氮源是豆粕粉和6%~8%玉米浆粉;较适宜的碳源是玉米面;维生素B1添加量以10 mg/100 m L、微量元素锰添加量以0.01%Mn SO4为宜、培养基初始p H值以5.5为宜;培养温度22~24℃,接种量1%,培养基装量50 m L和5~7 d的培养时间有利于胞外多糖和菌丝虫草素的产生.  相似文献   

6.
蛹虫草液体的深层发酵   总被引:5,自引:0,他引:5  
以菌丝体质量浓度(干重)和发酵液中甘露醇浓度为指标,研究温度、初始pH值、培养时间等因素对蛹虫草液体培养的影响,得到蛹虫草摇瓶液体培养的最佳温度为25.0℃,初始pH值为6.10,培养时间为5 d;蛹虫草液体发酵最适培养基的组成为:20 g/L蔗糖+5 g/L蛋白胨+1 g/L MgSO4.7H2O。在此基础上进行小型分批式发酵罐实验,研究有利于蛹虫草生长及活性物质生成的pH控制策略。研究结果表明,pH分段控制的液体深层发酵对蛹虫草生长最为有利,菌丝体质量浓度为17.31 g/L,甘露醇质量浓度达43.47 g/L。  相似文献   

7.
《贵州科学》2021,39(4)
通过平板培养的方式,观测不同碳源、氮源、温度、起始pH值4个因素对韦伯灵芝菌丝生长的影响。结果表明,韦伯灵芝菌丝在营养利用方面,适宜生长的碳源为糊精,适宜生长的氮源为酵母粉;在环境适应方面,适宜生长的温度范围为28~32℃,生长的最适起始pH值是6。  相似文献   

8.
通过对蛹虫草(Cordyceps militaris)菌丝液体发酵产纤溶酶的实验研究,获得了蛹虫草纤溶酶液体发酵的适宜参数.结果表明,蛹虫草菌丝液体发酵产纤溶酶的适宜碳源为玉米粉和蔗糖,豆饼粉和较高浓度的玉米浆(8%~12%)作为氮源是适宜的,培养基中适量添加Mg SO4(0.05%)、KH2PO4(0.1%)和Ca Cl2(0.05%)、Mn SO4(0.05%)等无机盐有利于蛹虫草纤溶酶产生;发酵p H值以4.5~5.5为宜,温度以22~24℃为宜,培养时间以6~7 d为宜.  相似文献   

9.
优化条件对蛹虫草菌丝体与胞外多糖得率研究   总被引:1,自引:0,他引:1  
采用摇瓶法对蛹虫草无性型菌种(ACCC 50383)菌丝体发酵培养,以菌丝体与胞外多糖得率为指标,通过单因素方差分析、S-N-K多重比较和回归方程分析,分别考察6种碳源和6种氮源,确定最适碳源为蔗糖,最适氮源为大豆蛋白胨;对发酵条件的研究表明,获得较高产率的发酵时间为6 d,最适发酵温度为(26.3±0.9)℃,发酵液初始pH值对发酵产率无影响,获得最大发酵产量时装液量为(208±28)mL。  相似文献   

10.
以槐耳菌丝体生物量为主要指标,采用不同碳源和氮源进行单因素初选试验,然后以不同比例的混合碳氮源进行正交试验.结果表明,槐耳菌丝体液体最佳培养基是玉米渣200g/L,蔗糖20g/L,酵母膏3g/L,麦麸3.5g/L,KH2PO42.0g/L,MgSO4·7H2O1.0g/L和VB1 6mg/L,温度28℃,pH自然.其菌丝体生物量得率为21.6g/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 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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