三塘湖油田头屯河组流动单元划分及微观渗流特征

为了指导三塘湖油田头屯河组储层的开发,针对储层特征,选择渗透率、压实校正后的孔隙度及孔喉半径R353个参数进行聚类、判别分析,将头屯河组划分为4类流动单元,各流动单元与沉积微相具有很好的对应关系。水驱油实验中,A类流动单元,水呈活塞式推进,驱油效率高;B类呈树枝状推进,驱油效率中等;C、D类呈指状推进,驱油效率低。微观孔隙结构的差异是造成驱油效率差别的主要原因。C、D类流动单元在研究区分布面积广,残余油多,是剩余油富集区。     

基于图像技术的微位移检测方法及其应用

为提高刚度测量中位移检测的精度,提出一种图像式微位移检测方法.该方法采用边界拟合和"路径匹配"技术,使位移量的检测精度达到了亚微米级.此微位移检测方法已用于弹性元件刚度测量仪中,并采用激光干涉仪进行标定.实验结果表明,微位移检测方法稳定性好,速度快且获得了优于0.1μm的精度.     

稀土在BNbRE重轨钢中的作用机制

通过化学分析、金相观察和理论分析,研究了稀土在BNbRE重轨钢中的存在状态和含量的变化规律,以及它对钢的硫化物夹杂、微观组织和性能的影响机制。研究发现,对于BNbRE重轨钢,加入大量的稀土并不能增加钢中固溶稀土的含量,固溶稀土的含量均保持在0．0012％以下。少量的固溶稀土可以细化BNbRE重轨钢的奥氏体晶粒和珠光体片层结构。在本实验条件下,BNbRE重轨钢的最佳稀土加入量约为0．02％,此时BNbRE重轨钢的塑性和冲击韧性得到显著提高。     

微量水蒸气对密封继电器内部氮气电弧的影响

密封继电器常充以一定气压下的保护性气体,以达到增加动作可靠性和延长触头使用寿命的目的。为研究常见保护性气体高纯氮气中不可避免喊有的其他杂质气体对原电弧的影响,针对高纯氮气中混有部分水蒸气的情况建立了热平衡态电弧微观模型;根据道尔顿分压定律、质量作用定律、电荷准中性条件和化学计量平衡条件得到关于各类粒子数密度的非线性方程组;结合具体电弧温度值求解并通过各类粒子数密度的变化来分析水蒸气作为杂质气体对氮气电弧的影响。结果表明:水蒸气的存在会削弱氮气相关电离过程;且电弧温度愈高,其影响愈明显。     

氮气吸附法的致密砂岩孔隙结构分析

微观孔隙结构特征是研究储层中油气储存和运移的关键因素。选取鄂尔多斯盆地西峰地区长8段致密砂岩储层中的样品。通过氮气吸附实验,获得致密砂岩样品的孔隙结构参数。并讨论了各个结构参数与物性的相关性和影响因素。实验结果表明:根据IUPAC的分类,微观孔隙结构属于H3型。比表面积与孔隙度呈一般负相关,与渗透率具有较强的负相关性。微孔(<10nm)与中孔(10～50nm)对比表面积与孔隙体积贡献了80%。孔隙体积与孔隙度和渗透率的相关性均呈现一般正相关性。综合以上,较少的大孔发育可能是导致致密砂岩渗流能力较弱的原因。     

5％NaOH改性葵花籽皮微观性状研究

采用5%NaOH改性处理葵花籽皮,并用SEM、BET及热重分析等表征改性葵花籽皮的微观性状。结果表明,NaOH将葵花籽皮中易溶基质溶解,粗纤维被分离并变得松散,比表面积较未改性葵花籽皮减少,孔径增加,平均孔径为29.26 nm,主要是粗纤维之间形成的狭长缝形孔。5%NaOH改性葵花籽皮热解主要经历了三个阶段,最主要的失重过程在第二阶段,失重率为61.31%,305℃出现最强失重,失重速率为0.61%·℃~(-1)。     

Systematic approach to the correct identification of Asplenium dalhousiae (Aspleniaceae) with their medicinal uses

In present study, multiple microscope techniques were used for the systematics identification of the species Asplenium dalhousiae. The plant was collected from different phytogeographical and its natural habitat of Pakistan, where it shows higher diversity. Morphology, foliar epidermal anatomy, and spore morphological characters of the species were studied in detailed using multiple microscopic techniques through light microscopy (LM) and scanning electron microscopy (SEM). LM and SEM were used for the systematics identification of the species. Traditionally, the species is used in the ailment of many diseases, so the spore morphology, anatomical features, and morphological characters are relevant to describe the species taxonomy. The importance of multiple methods of taxonomic study (e.g., documentation and morphological characteristics) for characterizing herbs are important step in systematic certification to maintain the efficacy of herbal medicines. The aim of the present study is to examine the morphological, anatomical, and spore morphology of the species A. dalhousiae in more detailed for the correct taxonomic identification and their medicinal validation from Pakistan.     

Implementation aspects of a phase-field approach for brittle fracture

This paper provides a comprehensive overview of a phase-field model of fracture in solid mechanics setting. We start reviewing the potential energy governing the whole process of fracture including crack initiation, branching or merging. Then, a discretization of system of equation is derived, in which the key aspect is that for the correctness of fracture phenomena, a split into tensile and compressive terms of the strain energy is performed, which allows crack to occur in tension, not in compression. For numerical analysis, standard finite element shape functions are used for both primary fields including displacements and phase field. A staggered scheme which solves the two fields of the problem separately is utilized for solution step and illustrated with a segment of Python code.     

聚合物表面活性剂溶液微观驱油特征*

为从微观研究聚合物表面活性剂(简称聚表剂)的驱油机理和驱油效果,采用微观刻蚀仿真模型进行微观可视化驱油实验,并与岩心驱替实验驱油效果对比。结果表明,在微观驱油实验中,水驱后微观模型中产生6种类型残余油,而聚表剂驱后对盲端残余油的驱替效果不明显;聚表剂的驱油机理主要是通过其增黏作用、黏弹性作用和乳化作用来扩大波及体积,降低渗流阻力",拉""、拽"残余油,将大油滴乳化分散成小油滴,从而将残余油有效驱出;不同浓度的聚表剂在微观模型和岩心驱替实验中的驱油效果基本相符,聚表剂浓度越大,残余油启动能力越高,驱油效果越好。聚表剂质量浓度为2000 mg/L时的驱油效果最好,采收率增幅为19.69%。图27表1参15。