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1.
本研究以甜菜渣为原料经厌氧发酵生产沼气。实验采用出料废沼液和干甜菜渣按20%浓度配比作为进料,投料率为5%,滞留期20天,温度控制在35—40℃,碳氮比为30:1,pH7.2—7.5,产气率可达到4.0M~3/M~3·日左右。厌氧微生物消化(Anaerobic Digestion)是处理工、农业废弃物的有效方法之一。近年来,由于能源需求量的迅速增长,发展代用能源的需求已变得日益显著。从工农业生产的有机残渣及废水中经厌氧消化生产甲烷通过大量的试验证明在技术上是可行的(G. Lettinga, "Anaerobic Digestion",1979,曾用厌氧消化法处理甜菜废水)。但用甜菜废渣经厌氧消化制取沼气在国内还是一项新的研究课题。为了开发新的能源资源,结合我国北方地区制糖工业中废甜菜渣资源丰富的具体情况,在小型发酵条件实验的基础上,在建平县第一糖厂利用6.5M~3卧式厌氧发酵罐进行了中试发酵实验。  相似文献   

2.
平菇液体菌种发酵条件的研究   总被引:1,自引:0,他引:1  
对平菇液体菌种的碳氮营养需求及培养条件进行了研究.结果表明:黑平王(平菇)菌株能利用多种碳氮源,其中碳源以玉米粉为最好,有机氮优于无机氮,豆饼粉为最佳氮源.培养基最佳组合为玉米粉2%,豆饼粉1.5%,KH2PO4 0.15%,MgSO4 0.1%,pH6.最适培养条件为25℃,摇床转速140r/min,接种量8%,装液量为100mL发酵液/300mL三角瓶,发酵时间为4d.  相似文献   

3.
鸡粪高温(50℃)厌氧消化的实验室试验结果表明,进料浓度为3%vs和6%vs,滞留期为10d和5d的平均产气率分别为0.9,1.4、1.5,2.2 L·L~(-1)·d~(-1)。从产气率、滞留期、甲烷含量、发酵液中挥发酸和NH_4~+-N含量分析,进料浓度3%vs,滞留期为5d可得到理想的处理效果。  相似文献   

4.
用实验室发酵罐,发酵液的投料浓度为原发酵液增加含糖量<2%。黑曲霉JIES—1变菌糖学粉酶的活力平均达16601mg·Per·h/ml,最高达1811mg·Per·h/ml,提高产率41.2%。发酵周期平均为107.2h,每小时产酶活力136.2mg·Per·h/ml。  相似文献   

5.
对苏北地区3种杨农复合经营模式(宽窄行模式即K模式、片林模式即P模式和网格模式即W模式)的100 cm土体8个土层中土壤有机碳、氮的分布进行研究,结果表明:3种模式土壤有机碳、氮含量及储量的剖面分布均表现出在表层相对较高,都有随土壤剖面深度增加而降低的趋势,且耕作层以下迅速降低。3种模式深度100 cm的土壤有机碳含量变化范围为0.64~1527 g/kg, 全氮含量变化范围0.30~2.09 g/kg;土壤有机碳含量与全氮含量及C/N呈极显著相关关系;100 cm深土壤有机碳储量在3种模式中分别达(71.19±0.72)、(40.67±058)和(42.64±0.56) t/hm2。  相似文献   

6.
赖氨酸产生菌SK—F1—08应用于以酒精糟、白酒糟、碎玉米、啤酒糟等为原料生成的“多菌种混合同态发酵”生物饲料中,在2.5%营养液F协同作用下,该饲料赖氨酸产酸率平均为3.08%,最高可达到4.98%。  相似文献   

7.
采用Plackett-Burman和中心组合设计对影响二形栅藻固碳率的7个影响条件进行筛选优化.PB实验设计与统计学分析表明:光照强度、初始氮浓度和接种浓度是影响栅藻固碳率的3个关键因素.以固碳率为响应目标,对这3个因素进行中心组合设计,并经响应面法优化分析得到影响栅藻固碳率的二次回归方程模型,获得优化的二形栅藻最优固碳培养条件为光强227.82μmol·m-2·s-1,初始氮浓度152.40mg·L-1,接种浓度0.33g·L-1;模型预测最大固碳率为702.026mg·L-1·d-1,验证值为717.49mg·L-1·d-1.验证结果表明,所建立模型预测精度较好,可用于优化栅藻固碳培养.  相似文献   

8.
试验研究了CaO-TiO_2-Al_2O_3,CaO-Al_2O_3-SiO_2 及CaO-B_2O_3-SiO_2渣系中TiO_2,Al_2O_3。及B_2O_3 含量对钢水脱氮率的影响。在三个渣系中,随着 TiO_2,Al_2O_3 及B_2O_3 含量的变化,脱氮率有一最大值,其脱氮率可达 55%—65%。钢和渣中氧位愈低,脱氮率愈高。增加渣中碳、铅及钢中铝的含量,可以提高合成渣脱氮效果。  相似文献   

9.
在真空下用CZ法生长硅单晶时,经热力学分折和实验研究证明,硅单晶中碳的主要来源除石墨托与石英坩埚间的反应生成CO外,气氛中氧化组元(O_2,SiO等)亦与石墨器件反应生成CO。碳以CO形式进入融硅,使硅单晶中碳含量增加。本研究采用了对石墨器件表面涂SiC、Mo、ZrO_2和热解石墨等方法,并用石英保温筒代替石墨保温筒。在真空度为1~3×10~(-2)托下,投料300g,用CZ法生长硅单晶,其晶体尾部的碳量平均值,比原工艺晶体中碳的平均含量降低了45%。  相似文献   

10.
从离子极化的一般概念出发,建議了“极化能”的近似計算式(3),並由此发展了一个“非标准型”离子晶体晶格能的計算式(4)。利用(4)式,对202个不同类型的化合物的晶格能进行了計算,和实驗値比較,誤差小于±3%的占72.3%,在±3~5%占12.3%,在±5~10%的占12.9%,大于±10%的占2.5%。在202个化合物中,常见的M~ⅠX_2和M~ⅡY型化合物有135个,仅計它們的計算結果,誤差小于±3%的占84.5%,加上誤差在±3~5%的11.9%共达96.4%,沒有誤差大于±10%的。因此所得結果较为滿意,表明(4)式是一个较好的且较方程应用范圍更广的晶格能計算式。根据所得結果,建議可用(3)式去近似量度离子間相互极化作用的大小,从而可加深对离子极化概念的理解,有助于对化合物性質的进一步研究。  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
19.
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   

20.
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   

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