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1.
羊肚菌Morchellaesculenta菌株Me1 1和Me1 2的菌丝在PDA培养基、麦芽浸粉培养基和酵母膏培养基上的生长虽然存在差异 ,但长势均良好 ,且均以在酵母膏培养基中长势最好 .在酵母膏培养基上培养时菌株Me1 1和Me1 2在被测的五种温度 4℃、1 0℃、1 7℃、2 5℃和 30℃中 ,以 2 5℃下培养的生长最为良好 .在酵母膏培养基上 ,菌株Me1 2的菌丝体呈褐色 ,菌株Me1 1的菌丝体呈淡色 .羊肚菌菌丝能否形成菌核与培养温度、培养基类型和菌株本身等因素有关 ,菌株Me1 2产生菌核较菌株Me1 1多  相似文献   

2.
利用植物细胞工程技术及组织培养技术:①离体快繁含长春花碱及长春新碱高的长春花幼苗.长春花离体快繁诱导与芽增殖的培养基为:MS+2.4-Dlmg·L~(-1)(单位下同)+ZT1,蔗糖30g·L~(-1),琼脂粉4g·L~(-1),pH5.4~5.8.诱导生根培养基为1/2MS+2.4-D1+KT0.4,蔗糖20g·L~(-1),琼脂粉和 pH 值同芽诱导培养基.②长春花植物细胞悬浮系的建立.愈伤组织诱导培养基为 MS+2.4-D1,MS+NAA1.86.长春花的开发研制工作从工业和农业二方面立体进行。  相似文献   

3.
通过集富培养、水解圈鉴定、酶活检测,从不同地点采集富含木聚糖的土样中初筛出10株木聚糖酶产生菌,选取酶活最高的Bacillus sp.No X-18菌株,进行单因素、双因素和培养基成分的综合优化试验.结果显示最佳培养基是:15%蔗糖、1%阿拉伯糖、0.37% NH4Cl、0.37%酵母膏、0.5% K2HPO4、0.02%MgSO4·7H2O,pH 80,其木聚糖酶活力可达74.21 IU/mL.  相似文献   

4.
海洋细菌1202菌株产胞外多糖的适宜条件   总被引:11,自引:0,他引:11  
应用响应面法(ResponseSurfaceMethod,RSM)对海洋细菌1202菌株胞外多糖发酵培养基进行优化.结果表明,适宜的发酵培养基组成为:蔗糖4%,酵母膏0.05%,玉米浆1.5%,CaCO30.15%,KH2PO40.08%,MgSO4·7H2O0.05%,FeSO4·7H2O0.01%,NaCl0.1%,pH7.5.在装液量为50mL(500mL三角瓶),接种量5%时,于28℃摇瓶培养7d,胞外多糖的产量可达到8.3mg/mL,转化率为20.75%.  相似文献   

5.
金合欢根瘤菌的生物学特性   总被引:1,自引:0,他引:1  
从金合欢根瘤分离到6株金合欢根瘤菌并鉴定这些菌株为快生型,该菌在酵母浸出物--甘露醇(YEM)培养基上产酸,代时在4小时以下,金合欢根瘤菌能利用包括双糖在内的大部分,碳源,但其中MXAF4,MXAF5和MXAF6不能利用大部分快生型根瘤菌能利用的蔗糖,事欢要胶 生长PH范围广(PH4.5-9),所有菌株能在37度条件下生长,其中MXAF4,MXAF5和MXAF6在40度仍能生长,而快生型大豆根瘤菌在37度条件下不能生长,金合欢根瘤菌对链霉素,庆大霉素和四环素敏感而对青霉素有抗性,金合欢根瘤菌根据石蕊牛奶反应可分面两群:菌株MXAF1,MXAF2和MXAF3石蕊牛奶反应产酸 乳清环,而菌株MXAF4,MXAF5和MXAF6产碱无乳清环。  相似文献   

6.
从地衣分离获得了Bt菌株BRC-ZQL3,为提高其产孢水平,应用数学统计方法对该菌株发酵培养基进行优化.通过单因子分析,研究碳源、氮源、初始pH等因子对产孢的影响;再采用2水平PlackettBurman设计,筛选影响产孢的8个因子,实验结果表明培养基成分中3个重要影响的因子,分别为CaCO3、玉米粉、酵母膏;利用响应...  相似文献   

7.
小冠花根瘤菌8406、MXCV1、MXCV2.MWCV3,MXCV4等五菌株的生理生化特性研究表明:8406、MXCV1、MXCV2在YEM培养基中生长较快,代时在5小时以下;而MXCV_3;MXCV4生长较慢,代时分别为8.0和8.4小时.所有菌株在YEM培养基中产酸,对单糖、双糖、多糖等多种碳源的利用行为相似,在碳源利用时大多产酸,对抗菌素的抗性特征等都与一般快生型根瘤菌相似.菌株对有机氮源利用较好,而利用无机氮源生长较差.石蕊牛奶反应中均出现血清环、产酸或产碱,菌株在34℃以上高温均不生长,生长pH范围为6.0—8.5,菌株的耐盐能力不超过0.1mol/L NaCl.小冠花——根瘤菌共生效应表明,菌株MXCV_2的接种效果最显著,有作为优良菌株用于生产菌剂的前景.  相似文献   

8.
采用单一因素确定法研究分离自明阳糖厂的一株肠膜明串珠菌菌株摇瓶发酵生产葡聚糖的适宜培养基 ,结果得到适宜培养基的组分为 :蔗糖 1 0 %、酵母膏 0 .4%、磷酸氢二铵0 .6%、磷酸二氢钾 0 .1 %、硫酸镁 0 .1 %、Mn Cl2 · 4H2 O0 .0 0 0 3%、Zn SO4· 7H2 O0 .0 0 0 5%、Fe SO4· 7H2 O0 .0 0 5%、Ca Cl2 · 2 H2 O0 .0 0 2 %。  相似文献   

9.
从养鸡场的鸡粪中分离出一株生长快、产酸能力强的乳酸菌株,经初步鉴定为植物乳杆菌,进一步研究其最佳生长条件为:最佳生长温度范围是25~28℃,以27℃最佳;最适pH值范围为4.5~7.0;耐盐性强,在4%NaCl浓度该菌也能良好生长。通过正交实验确定其最佳培养基配方为:蔗糖10g,酵母膏5g,牛肉膏6g,乙酸钠5g,MgSO4·7H2O0.5g,柠檬酸三钠2g,水1000ml,PH自然。  相似文献   

10.
MS培养基凝固效果和高温灭菌后pH值变化的研究   总被引:4,自引:0,他引:4  
研究了培养基的pH值、琼脂浓度与MS培养基凝固的关系 ,以及不同成分对高温灭菌后MS培养基pH值的影响 .结果表明 ,调高培养基的pH值或增加琼脂浓度均可改善培养基的凝固效果 ;高温灭菌后 ,MS基本培养基的pH值由灭菌前的 5 .80下降为 5 .5 1 ,造成pH值下降的最主要原因是高温灭菌过程中EDTA铁盐与其它微量元素发生相互作用所致 ;同基本培养基相比 ,培养基中加入 3 0 .0g·L- 1 蔗糖、食用白糖、葡萄糖或果糖使高温灭菌后的培养基的pH值分别下降了 0 .0 6、0 .1 0、0 .2 8和 0 .98个单位 ,而添加 2 .0g·L- 1 水解酪蛋白、蛋白胨、酵母提取物或 1 .0~ 5 .0g·L- 1 活性炭则使高温灭菌后的培养基的pH值分别上升了 0 .2 3 ,0 .1 8,0 .3 9和 0 .1 9~ 0 .72个单位  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.
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 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   

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.
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   

18.
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   

19.
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   

20.
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   

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