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1.
一组高温混合菌对木质素纤维素的降解   总被引:3,自引:0,他引:3  
对秸秆中木质素纤维素的生物预处理进行研究.采用高温混合菌对滤纸和玉米秸秆进行降解实验.在50℃,第7天滤纸失重率为76.2%;第30天玉米秆失重率为34.23%,玉米秸秆中木质素、纤维素和半纤维素的降解率分别为56.36%,42.88%,62.77%.混合菌在50℃条件下对玉米秸秆中的木质素、纤维素、半纤维素均有较高的降解效果.  相似文献   

2.
目的研究对不同木屑投加量利用硫酸盐还原菌降解木屑中木质素和纤维素去除率问题,为木质纤维素的生物降解提供新方法.方法将先期富集培养的硫酸盐还原菌污泥置于Ⅰ,Ⅱ,Ⅲ,Ⅳ4个三角瓶中,Ⅴ号三角瓶作为空白试验,分别投加5 g,10 g,15 g,20 g,10 g质量的木屑,通过静态试验测定木质纤维去除率.结果Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ号容器中木质素的去除率分别为49.32%,54.97%,57.92%,63.57%,0.07%;纤维素的去除率分别为82.18%,86.36%,89.32%,90.82%,7.33%.硫酸盐还原菌利用1 g的硫酸盐能够去除1 g的木质素.扫描电镜下观察经过硫酸盐还原菌降解后的木屑,发现木屑表面以及内部的结构均受到损伤,木质素和纤维素的结构被破坏.结论硫酸盐还原菌对木质纤维素有良好的降解作用.  相似文献   

3.
为了促进堆肥中木质纤维素降解并了解其中微生物群落代谢功能多样性,该文主要采用Biolog微平板法,考察了添加菌剂对牛粪堆肥中木质纤维素降解及微生物群落代谢能力的影响。结果表明:堆肥结束时,菌剂处理的堆肥中纤维素、半纤维素和木质素的降解率分别比对照提高了31.31%、19.57%和14.33%;对平均色度变化分析表明接种菌剂增加了堆肥高温期微生物的细胞代谢能力;Shannon指数、Simpson指数和McIntosh指数分析均显示添加菌剂可以显著提高堆肥前期的微生物多样性;主成分分析结果显示,添加菌剂提高了堆体中微生物对双亲化合物、聚合物、氨基酸和氨基化合物等碳源的代谢能力,从而可促使有机质被更高效降解。  相似文献   

4.
研究不同接种方法对蔬菜废物高温好氧降解的影响,探讨不同降解阶段的生物质降解情况.结果表明,接种率越高,越有利于蔬菜废物的降解;分段接种比茵悬液接种更有利于蔬菜废物中有机物的降解,尤其是对纤维素的降解;以生物质降解状况为依据的接种,在堆肥原料季节性变化的条件下,可优化微生物接种的效果.  相似文献   

5.
针对传统堆肥周期长、有机质降解效率低的问题,将耐热复合菌剂接种于餐厨废弃物高温堆肥中,研究其对有机质降解及微生物群落动态变化的影响。结果表明,接种耐热复合菌剂有利于:有机质降解,堆肥细菌群落丰富度和多样性的提高,厚壁菌门(Firmicutes)和尿素芽胞杆菌属(Ureibacillus)相对丰度的提高,冗余分析的结果表明,厚壁菌门(Firmicutes)对有机质降解的影响最强;网络分析结果表明,堆肥过程中尿素芽孢杆菌属(Ureibacillus)相对丰度的增加以及乳杆菌属(Lactobacillus)相对丰度的降低促进了有机质的降解。因此,接种耐热复合菌剂可以提高高温堆肥的质量和效率。  相似文献   

6.
提出了一种对毒死蜱污染土壤的生物修复方法.该方法主要从土壤中筛选出一株适合接种到堆肥体系中的毒死蜱降解菌Y3,并采用4个堆制体系考察在接种与不接种菌株Y3的两种堆肥化条件下,土壤中残留的毒死蜱对堆肥进程的影响和毒死蜱的降解情况.结果表明不接种降解菌Y3的堆制B能够在40 d的堆制时间内达到腐熟,并且在堆制第32 d时使土壤中的毒死蜱被完全降解.接种降解菌Y3的堆制C能够更快消除堆肥中植物毒性,减少堆肥腐熟的时间,并且使毒死蜱被完全降解的时间缩短了12 d,接种筛选的降解菌Y3堆肥修复毒死蜱污染土壤的方法切实可行.  相似文献   

7.
采用连续传代方法分别从自制堆肥和几种自然发酵基质中筛选出纤维素分解能力较强的两组混合菌复合系MC-A1和MC-N1,前者是通过高温摇瓶发酵定期传代获得的耐高温好氧性的纤维素分解菌群,后者则是通过高温静止培养定期传代获得的耐高温兼氧性的纤维素分解菌群,这两组纤维素分解菌复合系在96 h内对天然纤维素材料麦秆粉的分解率分别达到42%和38%,分解速度最快时期均发生在48~96 h内,96 h以后麦秆粉分解率迅速减缓。麦秆粉发酵培养液先接种好氧性纤维素分解菌复合系MC-A1摇瓶发酵96 h,再接种兼氧性纤维素分解菌复合系MC-N1静止培养96 h,麦秆粉的分解效率可以提高到47%,说明这两组纤维素分解菌复合系在非天然纤维素分解过程中发挥协同作用。  相似文献   

8.
以农作物秸秆,包括水稻秸秆、玉米秸秆和甘蔗渣为材料,采用分光光度法比较了烟曲霉、绿色木霉、枯草芽孢杆菌的处理效果.实验结果显示:总乙醇产量最高的是甘蔗渣,其乙醇体积分数为6.285%;而玉米秸秆和水稻秸秆相差甚微,分别是6.200%和6.195%.用2%(体积分数)氢氧化钠溶液预处理甘蔗渣,再用烟曲霉在28℃下降解甘蔗渣,最后用缺陷型酵母发酵预处理滤液和烟曲霉降解液20~25 h,可以提高木质纤维素降解、转化乙醇的效率.  相似文献   

9.
为进一步提高堆肥物料中纤维素的降解效率,缩短堆肥时间,研究将前期复配的纤维素降解复合菌剂M(M)接种羊粪和秸秆混合物,并开展好氧堆肥发酵试验,分析菌剂M羊粪堆肥发酵的效果.结果表明,添加菌剂M发酵后,与空白对照组(CK)相比,堆体的升温(50℃)时间缩短了1 d,高温阶段延长了2 d,腐熟周期缩短了4 d.堆肥结束(25 d)时,添加菌剂M处理组的碳氮比(12.77)显著低于CK组(16.44)(p0.05),而且种子发芽指数(98.20%)、全氮(23.37 g·kg~(-1))、P2O5(13.13 g·kg~(-1))、K2O(51.12 g·kg~(-1))、纤维素降解率(28.33%)和半纤维素降解率(38.32%)均显著高于CK处理组(p0.05),总养分(8.76%)达到国家有机肥料标准(≥5%).酶活测定表明,堆肥过程中,添加菌剂M处理组的滤纸酶(FPase)、羧甲基纤维素酶(CMCase)和β-葡萄糖苷酶(β-Gase)均显著高于CK处理组的(p0.05).其中,在发酵高温阶段(4~8 d)时的酶活最高,分别为57.80、10.41 U·mL~(-1)和75.77 U·mL~(-1).将菌剂M与市售促腐菌剂R(菌剂R)混合的菌剂MR堆肥,各项指标均优于菌剂M和菌剂R单一处理组的.除纤维素降解率外,菌剂M和菌剂R处理组的其它各项指标之间无显著差异(p0.05).试验利用复合菌剂M进行羊粪堆肥发酵可以明显降低堆体物料的纤维素和半纤维素,提高堆肥营养,缩短堆肥时间,发酵后的有机肥可用于农业生产.  相似文献   

10.
为了拓展厌氧消化原料的来源,以平菇菌渣为研究对象进行沼气发酵试验.在中温(35±1)℃条件下,采用批量式发酵工艺,对其产气特性及有机质含量变化与厌氧消化之间的关系进行分析.试验结果表明,平菇菌渣是一种较佳的发酵原料,其原料产气率为464 mL/g、TS产气率为619 mL/g、VS产气率为720 mL/g.在沼气发酵过程中,纤维素、半纤维素、木质素、粗脂肪、粗蛋白、总糖、低聚糖、还原糖和淀粉均不同程度的发生降解,其中纤维素和低聚糖的降解率远高于其他有机质,纤维素几乎全部降解,低聚糖降解率达到了90%以上.该试验结果为平菇菌渣的无害化、资源化利用提供理论研究基础和数据支持.  相似文献   

11.
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   

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

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
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.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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