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1.
采用唯一碳源法从土壤中分离了一株具有聚己内酯(PCL)降解能力的真菌DSWJ1201,对其进行了形态学和分子生物学鉴定,结果表明该真菌为短密青霉(Penicillium brevicompactum);结合单因素实验和正交试验对菌株产PCL解聚酶的条件进行了优化,结果显示出当培养温度为20℃、培养基初始pH值为7.0、装液量为250mL三角瓶装液100mL、PCL质量的浓度为0.6g/L、诱导物(吐温80)体积分数为2.5mL/L、发酵时间为5d时,菌株所产粗酶的酶活力最高.同时还发现菌株DSWJ1201具有耐冷菌的特性,且能够降解表面活性剂吐温80,因此在常温和低温条件下的废弃物处理中具有潜在的应用价值.  相似文献   

2.
对云芝菌产漆酶的发酵条件进行优化,考察C源、N源和诱导剂等因素对产酶的影响.结果表明:杂色云芝菌摇瓶产漆酶的最佳条件为葡萄糖1.25 g/L,羧甲基纤维素钠15 g/L,酵母膏15 g/L,KH2PO41 g/L,CaCl20.05 g/L,MgSO40.25 g/L,30℃、150 r/m条件下振荡培养,在72 h加入2 mmol/L 2,5-二甲基苯胺作为诱导剂,在96 h加入2 mmol/L Cu2+,经过7 d培养,菌的漆酶比活达到3 319.2 U/mL.  相似文献   

3.
从碱性土样中分离出的1株哈茨木霉(T.harzianum),液体发酵条件的实验表明,产酶最适的培养基初始pH为7.5,培养温度为28℃,摇床转速为160r/min;最适的单一碳源为麸皮,添加量为质量分数3.0%~5.0%;添加质量分数0.5%左右的复合氮源有利于产酶的提高;诱导物纤维素CF—11和微晶纤维素的最适添加量分别为质量分数2.0%和1.0%;添加吐温80有利于产酶的提高,添加量质量分数0.2%;用300mL三角瓶液体摇床发酵时装样量80mL左右为宜;发酵周期5~6d,获得的粗酶液的内切酶活最高为1.85U/mL,FPA为0.96U/mL.水杨素酶活为0.81U/mL。  相似文献   

4.
研究了培养基初始pH值、通气量、温度、表面活性剂、诱导剂、金属离子对云芝(Trametes versicolor)HS-03产漆酶发酵条件的影响.研究发现培养基的初始pH、培养温度、表面活性剂、诱导剂和金属离子等因子对该菌漆酶产量均有明显的影响.结果表明,云芝摇瓶产漆酶的最佳培养条件为培养基初始pH为3.5,转速150 r/min,培养温度28℃,另加1 mL/L吐温-80,1 mL/L愈创木酚,终浓度为0.5 mmol/L的Cu2 .在该条件下,该菌的漆酶酶活力达到291 U/L,比优化前提高了8倍,同时产酶高锋也提前了5 d.  相似文献   

5.
为消除人造板中游离甲醛污染问题,采用漆酶处理木材生产无甲醛人造板是未来发展的重要方向之一。为探讨漆酶处理木纤维最佳工艺条件,采用两种漆酶(白腐菌漆酶,漆酶Ⅰ、曲酶菌漆酶,漆酶Ⅱ)处理思茅松边材,处理条件为pH(2.0~6.0),温度(30~80)℃,时间为1h,2h.3h,酶用量分别为10u/g、20u/g、30u/g,并测定处理后木材的活性氧自由基(Ros)浓度。结果表明,漆酶处理后思茅松边材ROS浓度显著提高;pH值、温度、处理时间和酶用量对ROS浓度变化均有影响,本试验条件下两种漆酶处理思茅松木材的最佳工艺条件为pH3.0、50℃,2h,20u/g。  相似文献   

6.
糙皮侧耳Ax3产漆酶条件及部分酶学性质研究   总被引:11,自引:0,他引:11  
对糙皮侧耳(Pleurotus ostreatus)Ax3菌的漆酶产生条件进行了研究,该菌产漆酶较高的条件是:培养温度25℃,培养基pH5.5,每升C/N含量0.252g/0.021g;加入0.05%~0.1%的吐温可提高漆酶酶活12倍。对漆酶的部分生化性质研究表明:最适反应温度25℃;最适反应pH2.8;琥珀酸缓冲液效果最好;金属离子:Mn^2 ,Cu^2 ,Zn^2 对漆酶有较强的激活作用,其中Mn^2 相对活性最高,Ag^ ,K^ ,Ca^2 ,Fe^2 对漆酶活性有抑制能力,其中Ag^ 的抑制作用明显。  相似文献   

7.
采用愈创木酚显色法筛得一株产漆酶周期较短的丝状真菌.通过形态学观察和分子生物学序列分析,鉴定其为棘孢木霉(Trichodermaasperellum),并对所获菌株进行了发酵条件优化.通过单因素试验和正交试验获得该菌的最佳发酵条件为:蔗糖25 g/L、麸皮汁80 g/L、酒石酸铵10 g/L 和豆粕18 g/L,KH2 PO42, MgSO4?7H2 O 0.6,CaCl2?2H2 O 0.8,Cu2+0.25(1 mM),pH 5.5~6.5,其漆酶最高酶活水平为571.32 U/L.  相似文献   

8.
对分离到的一株可产生橡Wan单宁降解酶,并有较高鞣花酸产率的曲霉发酵条件进行了研究。结果表明,该菌产橡Wan单宁降解酶的适宜培养条件为:培养液的橡Wan单宁浓度为5.0g/L、蔗糖20g/L、蛋白胨6.0g/L,起始pH5.0,250mL三角瓶培养液装液量为100mL,30℃、120r/min摇床培养48h。该酶在pH为4.0-5.0、温度30℃时稳定性最好。  相似文献   

9.
为了实现绿色木霉菌Trichoderma viride来源的β-葡萄糖苷酶在重组毕赤酵母中的高效表达,对重组菌P.pastoris KM71/pPIC9K-bgl1/pPICZ A-pdi进行3.6L罐发酵培养条件优化。结果表明,当诱导温度28℃,初始诱导菌体浓度50g/L,诱导阶段甲醇体积分数1.0%时,酶活力最高,能达到1452U/mL。同时以壳聚糖为载体、戊二醛为交联剂,采用吸附交联法对β-葡萄糖苷酶进行固定化。结果表明,当壳聚糖质量浓度0.03g/mL,戊二醛质量浓度0.008g/mL,游离酶添加量400U/g(1g壳聚糖微球加酶量为400U),固定化吸附时间20h时,固定化酶酶活回收率最高,达到65.4%。以800g/L葡萄糖为底物,优化的转化条件下连续转化6次,低聚龙胆糖产率仍达到15.2%,显示出该固定化酶具有较好的持续利用性及较高的低聚龙胆糖生产能力。  相似文献   

10.
利用紫外线-60Co-γ、微波及硫酸二乙酯诱变新月弯孢霉菌株,使其产漆酶能力大幅度提高。漆酶活性由原来的0.55 μmol/(min·mL)提高到1.949 μmol/(min·mL)。进一步通过单因素实验及正交实验得出最佳产酶条件为:发酵温度30 ℃,发酵时间72 h,培养基pH为 6,装液量120 mL,摇床转速160 r/min,土豆200 g/L,蔗糖30 g/L,大豆蛋白胨5 g/L,KH2PO4 5 g/L,愈创木酚0.2 mmol/L,吐温80 0.1 mL/L,Mg2+ 0.5 mmol/L,Cu2+ 1 mmol/L,Ca2+ 1 mmol/L,Mn2+ 0.25 mmol/L。在此条件下,最终漆酶活性可达2.306 μmol/(min·mL)。  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.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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