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1.
研究了柠檬酸与重铬酸钠的反应历程、生成螯合物的结构以及Cr3 HPAM胶态分散体冻胶的性能。在75℃下用柠檬酸将重铬酸钠中的Cr6 还原为Cr3 ,同时与Cr3 发生螯合反应,生成柠檬酸铬螯合物。这种螯合物在一定条件下释放出Cr3 ,它与HPAM交联形成胶态分散体冻胶。实验表明,柠檬酸铬 HPAM胶态分散体冻胶体系最长的成冻时间为40d,最大强度为0.036MPa。用平行管岩心模型考察了冻胶的液流转向作用,调剖后高渗透层流量减小,液流转向低渗透层。  相似文献   

2.
研究了柠檬酸与重铬酸钠的反应历程、生成螯合物的结构以及Cr^3 -HPAM胶态分散体冻胶的性能。在75℃下用柠檬酸将重铬酸钠中的Cr^6 还原为Cr^ 3 ,同时与Cr^3 发生螯合反应,生成柠檬酸铬螯合物。这种螯合物在一定条件下释放出Cr^3 ,它与HPAM交联形成胶态分散体冻胶。实验表明,柠檬酸铬-HPAM胶态分散体冻胶体系最长的成冻时间为40d,最大强度为0.036 MPa。用平行管岩心模型考察了冻胶的液流转向作用,调剖后高渗透层流量减小,液流转向低渗透层。  相似文献   

3.
缓交联铬冻胶体系影响因素分析   总被引:2,自引:0,他引:2  
缓交联铬冻胶体系由部分水解聚丙烯酰胺、重铬酸钠与有机还原剂硫脲组成。由于硫脲的还原能力弱 ,因此该体系成冻时间较长 ,其终冻时间长达 8~ 10d ,可用于油藏的深部调剖。分析了铬冻胶的形成过程 ,通过测定成冻时间 (包括初冻时间及终冻时间 )和突破真空度评价了各种因素的影响。研究结果表明 ,随着交联剂质量分数的减少、pH值的升高 ,铬冻胶体系的成冻时间延长 ,强度增大 ;随着部分水解聚丙烯酰胺质量分数的增大 ,成冻时间缩短 ,强度增大 ;随着温度的升高 ,成冻时间缩短 ,强度变化不大  相似文献   

4.
长成冻时间的深部调驱剂是以 HPAM为主的复配聚合物 ,由树脂交联剂 1 0 3交联形成的 .由冻胶强度级别的划分定性地测定成冻时间和突破真空度的方法定量测定冻胶强度 .评价了不同聚合物、交联剂及矿化度在不同温度下的成冻时间及强度 ,并作出了成冻时间及强度等值图 .结果表明 :成冻时间在 1~ 3 0 d范围内可调 ,强度 (即 p BV值 )在 - 0 .0 6 0~ - 0 .0 3 0 MPa范围内可调 .由成冻时间和强度等值图可找出具体地层条件下的不同成冻时间及不同强度调驱剂配方  相似文献   

5.
碱木素冻胶是一种具有热稳定性且易于进入地层深部的高温堵剂,首先合成了碱木素冻胶的交联剂——水溶性酚醛树脂,优化了其合成反应条件,然后评价了碱木素高温冻胶的性能.研究结果表明:水溶性酚醛树脂的最佳合成条件为催化剂NaOH质量分数9%,甲醛与苯酚摩尔比1.8,反应温度85℃,自缩聚反应时间30 min.脱水后的水溶性酚醛树脂中羟甲基质量分数为83.54%,游离醛质量分数为0.35%,黏度为2 950 mPa.s,可在25℃下保存1个月,贮存稳定性好.在酚醛树脂质量分数为3.5%、碱木素质量分数为10%、体系pH值为9.75、高温200℃条件下碱木素冻胶的成胶时间为1.5 h,冻胶强度为0.092 MPa.成胶时间短,冻胶强度高,热稳定性好,具有较好的蒸汽调驱性能和应用前景.  相似文献   

6.
本文以水溶性酚醛树脂为交联剂,以纳米颗粒为稳定剂,以HPAM以及不同AMPS含量的聚合物为成胶剂,在低盐含量的模拟注入水中制备了稳定的冻胶。研究发现,相同交联剂和聚合物用量下,AM-AMPS共聚物成胶时间比HPAM长,但成胶后强度高。评价了制备的冻胶在不同盐含量模拟水中的脱水情况,结果表明,当模拟水盐含量为10000mg/L、30000mg/L时,冻胶会吸水膨胀、强度降低;但当模拟水盐含量高于50000mg/L时,冻胶则脱水,冻胶强度提高。模拟水盐含量越高,脱水幅度越大。提高冻胶中纳米颗粒的含量或用AMPS含量高的共聚物做成胶剂,可明显降低冻胶在高盐含量中的脱水幅度。研究结果对红河油田裂缝封堵剂的开发有指导意义。  相似文献   

7.
缓交联铬冻胶体系影响因素分析   总被引:7,自引:0,他引:7  
缓交联铬冻胶体系由部分水解聚丙烯酰胺,重铬酸钠与有机还原剂硫脲组成。由于硫脲的还原能力弱。因此该体系成冻时间较长,其终冻时间长达8-10d,可用于油藏的深部调剖,分析了铬冻胶的形成过程,通过测定成冻时间(包括初冻时间及终冻时间)和突破真空度评价了各种因素的影响,研究结果表明,随着交联剂质量分数的减少,pH值的升高,铬冻胶体系的成冻时间延长,强度增大;随着部分水解聚丙烯酰胺质量分数的增大。成冻时间缩短,强度增大;随着温度的升高,成冻时间缩短,强度变化不大。  相似文献   

8.
长成冻时间的深部调驱剂研究   总被引:14,自引:0,他引:14  
长成冻时间的深部调驱剂是以HPAM为主的复配聚合物,由树脂交联剂103交联形成的,由冻胶强度级别的划分定性地测定成冻时间和突破真空度的方法定量测定冻胶强度,评价了不同聚合物,交联剂及矿化度在不同温度下的成冻时间及强度,并作出了成冻时间及强度等值图,结果表明:成冻时间在1-30d范围内可调,强度(即pBv值)在-0.030MPa范围内可调,由成冻时间和强度等值图可找出具体地层条件下的不同成冻时间及不同强度调驱剂配方。  相似文献   

9.
HPAM凝胶是目前国内外采用最广泛、最有效的化学堵水调剖剂,其中苯酚/甲醛体系是HPAM凝胶类堵水调剖剂最常用的交联剂。但是苯酚/甲醛交联剂气味和毒性较大,尤其是高致癌性,严重限制了其在现场的应用。首先,在室内合成了低毒水溶性的羟甲基多酚THMBPA;其次,以THMBPA为交联剂主剂,以多乙烯多胺TET为交联剂辅剂,研究了部分水解的聚丙烯酰胺HPAM与THMBPA/TET复合交联剂的凝胶动力学,考察了p H值、复合交联剂配比、温度对成胶时间和凝胶长期稳定性的影响。实验结果表明,在120℃下,该凝胶体系的成胶时间可在10~120 h范围内任意调节。在120℃下凝胶可稳定存在90 d,在90℃下可稳定存在100 d。  相似文献   

10.
研制了一种以聚丙烯酰胺为主剂,复合树脂作为延迟交联剂的调剖堵水剂,并在室内考察了其性能。该堵水剂具有强度高、成胶时间在较宽范围内连续可调整、配制简单及操作方便等特点。该体系聚合物使用浓度低(0.1%~0.5%),基液粘度低,易注入;能满足温度为40~80℃的低渗透油藏调剖、堵水的技术要求;成胶时间在10 h~25 d范围内可调,满足深部调剖及大剂量调驱的技术要求;成胶后凝胶强度高,能对高渗透层(段)形成有效封堵;体系基液pH值5~7,基本呈中性,对注入设备、油水井管柱几乎不形成腐蚀;配制简单、操作方便;所有化工材料均为固体,运输储存方便。截至目前,现场累计应用290井次,效果明显。  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.
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   

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