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1.
为研究不同温度下油页岩细观结构的演化规律,利用显微CT试验分析系统,对产自抚顺的油页岩样进行显微CT扫描,结果表明:随着温度升高,试件内裂隙结构经历了"生成—闭合—再发育"的三个阶段,但整个油页岩试件的空隙率一直增大.选取含裂隙的局部区域作为研究对象,在100℃~300℃内,裂隙逐渐闭合导致区域内空隙团的数量增加但空隙团总体积减小;300℃~600℃内裂隙重新开裂并不断发育延伸,区域内大部分空隙团得以连通,空隙团数量减小但总体积增大.  相似文献   

2.
油页岩孔隙裂隙演化规律是影响对流加热方式原位流态化开采油页岩的关键影响因素。选取新疆巴里坤油页岩试样,首先利用自主研制的高温蒸汽作用实验系统对试样进行加热,然后采用显微CT和扫描电镜对不同温度作用后的油页岩的孔隙裂隙特征进行测试,并利用Avizo软件,对油页岩孔裂隙结构、内部渗流场特征以及表面微观特征随温度的演化规律进行了详细地研究,结果表明:1)原始状态下油页岩内部裂隙以微裂隙(100~500μm)为主,随着水蒸汽作用温度不断提高,微裂隙数量呈指数形式增长,同时孔径较小的小孔逐步转变为孔径较大的中大孔。2)随着水蒸汽作用温度增加,油页岩孔隙度显著增加,由常温状态下的2.7%增加到555℃时的16.2%,是常温下的6倍。3)随着热解温度的升高,油页岩内部连通的孔隙也不断增多,为高温水蒸汽以及热解产物的运移提供了良好通道,总体上平行层理方向的渗透率总是大于垂直层理方向的渗透率。4)油页岩渗透性存在明显的各向异性特征,当热解温度为314℃时,油页岩在平行层理方向与垂直层理方向的渗透率差异性最大,渗透率各向异性系数量级可达103.研究结论对调控水蒸汽对流加热原位开采油页岩油气的工艺参数具有重...  相似文献   

3.
为了研究高温状态下石灰岩力学性能,采用液压伺服刚性岩石力学实验系统对常温~800℃高温作用下石灰岩的力学性能进行了实验研究,分析了石灰岩应力应变曲线、峰值应力、峰值应变、弹性模量等的变化情况。研究结果表明:在600℃以内的高温下,温度对石灰岩的力学特性的影响不明显。但在600℃以后,随受热温度升高石灰岩力学性能迅速劣化,峰值应力和弹性模量急剧降低,而峰值应变迅速增长。800℃时已形成缓和的应力-应变全过程曲线,表现出软化现象。  相似文献   

4.
以晋城无烟煤为研究对象,利用μCT225 kVFCB扫描系统,在不同温度下对晋城无烟煤进行CT扫描,研究不同温度下裂隙发育状况。基于AVIZO三维可视化重构技术,对煤样内部裂隙进行提取。对单个裂隙进行了定量分析,对比了不同温度下热破裂和热解对裂隙发育的影响。实验结果表明:200℃时,微裂隙扩展形成长度L1 000μm的裂隙,在不同温度作用下,无烟煤孔裂隙的致裂原因不同;在常温300℃时,裂隙2发育剧烈,主要由热破裂引起,随着温度的升高无烟煤内部发生热解反应,裂隙发育主要受热解作用影响;400℃时,最大裂隙体积减小;600℃时,温度对裂隙发育影响最大,裂隙1和3相互连通扩展,同时次生裂隙生成。根据长度L的不同,晋城无烟煤内部裂隙分为3类:1μmL100μm; 100μm≤L1 000μm;L≥1 000μm.在不同温度作用下,综合单裂隙提取主裂隙面张量方向不同;随着温度的升高裂隙沿层理方向发育较快,其中在300℃与600℃时,裂隙空间发育最为显著。温度越高,三维裂隙体积变大,空间相互连通,渗透性增大,为煤层气抽采提供了高渗透性通道。  相似文献   

5.
为研究高温对地聚物砂浆的力学性能与导热性能的影响,以温度为变量设置了25℃、200℃、400℃、600℃、800℃这5种温度进行常规导热试验和单轴压力试验。试验获取了导热系数、应力-应变全曲线、抗压强度、峰值应变、切线模量等参数指标,并对不同高温作用后的地聚物砂浆进行了SEM和XRD试验,深入分析了不同温度对其力学性能与导热性能的影响规律,并建立了地聚物砂浆高温损伤模型。结果表明:(1)随着温度的升高,地聚物砂浆的导热系数呈现逐渐下降的趋势,温度为200℃时,相比于其他温度的导热系数下降幅度明显;(2)高温使地聚物砂浆的力学性能随温度的升高不断降低,并且随着温度升高,高温劣化作用越来越显著,使强度迅速下降;(3)高温会导致地聚物砂浆内部裂缝逐渐增多、C-S-H胶凝物质减少,在温度为600℃时C-S-H胶凝物质基本消失,800℃发生固相反应生成钙铝黄长石且砂浆内部细小裂缝转变为贯通型大裂缝;(4)建立了地聚物砂浆高温损伤模型。  相似文献   

6.
油页岩灰分是油页岩综合利用的主要物质之一。对石长沟油页岩进行马弗炉燃烧实验,制备不同燃烧终温(200~800 ℃)的油页岩灰分;并借助多种实验仪器研究不同温度燃烧下的灰分构成成分、结构特征及微观孔隙演化过程。结果表明:油页岩有机质以脂肪族为主;燃烧过程中,各有机元素(N、S、C、H、O)含量呈现下降趋势,自由水析出,结构水脱离,碳酸盐和脂肪族会逐渐分解,在800 ℃高温时,C完全转化为CO2逸出;灰分的构成成分主要为二氧化硅和碳酸盐,孔隙以微孔和中孔为主,随着燃烧温度升高,中孔数量增加,比表面积和分形维度先增后减,峰值均在400 ℃处。本次研究结果为分析石长沟油页岩不同燃烧温度下灰分的物理状态提供了理论基础,对了解石长沟油页岩的燃烧特性具有一定的借鉴意义。  相似文献   

7.
利用热重仪对新疆油页岩进行不同温度下的热解实验,结果显示热解温度高低和油页岩在特定温度下的热解时间都会明显影响到油页岩的失重率,热解新疆油页岩的最佳温度值为500℃;通过高精度显微CT实验系统对热解后油页岩的细观进行测试,得到注蒸汽原位开采油页岩是完全可行的结论,这对油页岩原位开采技术的发展具有重要意义。  相似文献   

8.
考虑换热器管板胀接接头和高温拉伸实验机结构,设计了试件和实验方案,对液压胀接接头在高温条件下的拉脱力变化规律进行了实验研究.当温度在100℃内,拉脱力随温度升高显著增大、受胀管率影响较大;当温度在100℃~300℃时,拉脱力随温度升高略有降低,胀管率影响逐步变小.实验结果可为换热器管板胀接接头设计和拉脱力计算提供理论依据.  相似文献   

9.
利用自主研发的WYF-I型高温高压热解反应装置及基于岩芯柱脉冲衰减法研制的Smart perm Ⅲ型气体渗透率测量仪,对抚顺西露天矿油页岩试件进行20~600℃范围内的热解试验,研究不同热解温度和应力条件下的油页岩渗透率变化规律。试验结果表明,油页岩热解过程呈明显阶段性变化。第一阶段:20~300℃,油页岩失重率和孔隙率变化较小,渗透率随热解温度变化不明显,体积应力对渗透率影响较小。第二阶段:300~400℃,油页岩失重率和孔隙率迅速增加,试件渗透率增加了24.3~92.4倍;体积应力对渗透率影响明显,当体积应力由13MPa增加至39MPa后,孔隙压力1MPa下的渗透率降低了22.23%.第三阶段:400~600℃,失重率和孔隙率进一步增加,但增速减缓,温度对渗透率影响减弱,400℃增加至600℃时油页岩渗透率仅增加了1.69~2.49倍;体积应力对渗透率影响增强,体积应力增加导致渗透率下降了32.84%~41.79%.研究结果对原位热解开采油页岩时热解温度的合理选取有一定的参考价值。  相似文献   

10.
大庆普通稠油粘温及流变性研究   总被引:1,自引:0,他引:1  
以大庆江37普通稠油为研究对象,利用Anton Paar MCR301旋转流变仪开展了稠油黏温及流变特性的实验研究。通过室内实验,测定了大庆普通稠油在不同温度、压力及剪切速率条件下的黏度,研究了稠油流变性特性及屈服应力与温度的关系。研究结果表明,稠油的黏度对温度非常敏感,随温度升高而大幅度降低,在拐点温度处之前,稠油黏-温关系曲线随压力变化较大;在拐点温度处之后,压力对黏度影响不大。流变性曲线说明,低温40℃条件下稠油油样属于Bingham塑性流体。随着温度升高,原油流变性表现为牛顿流体特性。  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.
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   

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.
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.
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   

17.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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