郑408火烧驱油注气井油管腐蚀与防护

文章对胜利油田郑408火烧驱油注气井油管腐蚀产物进行了X射线衍射分析(XRD)和电子探针显微分析(EPMA),初步认定:上部管柱主要是氧腐蚀;下部腐蚀严重部位为氧加速的酸性垢下腐蚀穿孔。实践表明,“钛纳米聚合物防腐蚀涂层油管”和“镀钨合金防腐蚀油管”在上述环境使用较为适合;同时应注意郑408井如再需压井作业,可以同时注入缓蚀剂来减缓压井液对油、套管的腐蚀。     

Nonisothermal crystallization kinetics and thermomechanical properties of multiwalled carbon nanotube‐reinforced poly(ε‐caprolactone) composites

BACKGROUND: The technological development of poly(ε‐caprolactone) (PCL) is limited by its short useful lifespan, low modulus and high crystallinity. There are a few papers dealing with the crystallization behavior of carbon nanotube‐reinforced PCL composites. However, little work has been done on the crystallization kinetics of melt‐compounded PCL/multiwalled carbon nanotube (MWNT) nanocomposites. In this study, PCL/MWNT nanocomposites were successfully prepared by a simple melt‐compounding method, and their morphology and mechanical properties as well as their crystallization kinetics were studied. RESULTS: The MWNTs were observed to be homogeneously dispersed throughout the PCL matrix. The incorporation of a very small quantity of MWNTs significantly improved the storage modulus and loss modulus of the PCL/MWNT nanocomposites. The nonisothermal crystallization behavior of the PCL/MWNT nanocomposites exhibits strong dependencies of the degree of crystallinity (X_c), peak crystallization temperature (T_p), half‐time of crystallization (t_1/2) and Avrami exponent (n) on the MWNT content and cooling rate. The MWNTs in the PCL/MWNT nanocomposites exhibit a higher nucleation activity. The crystallization activation energy (E_a) calculated with the Kissinger model is higher when a small amount of MWNTs is added, then gradually decreases; all the E_a values are higher than that of pure PCL. CONCLUSION: This paper reports for the first time the preparation of high‐performance biopolymer PCL/MWNT nanocomposites prepared by a simple melt‐compounding method. The results show that the PCL/MWNT nanocomposites can broaden the applications of PCL. Copyright © 2008 Society of Chemical Industry     

砾石颗粒干比重及饱和面干比重的估算方法--应用于最大干密度校正

砾石颗粒的饱和面干比重(Gs3)、干比重(Gs2)与其本身矿物成分、孔隙比、孔隙特征有着密切关系.文章提出了以砾石颗粒的饱和面干含水量及相应的粒径小于5 mm土粒的比重估算其Gs3,Gs2的方法,旨在简化土的最大干密度的校正工作.以该估算方法估算的Gs3或Gs2,校正土的最大干密度,所产生的误差之绝对值小于0.01 g/cm3,对实际工程的影响是无关紧要的.     

土样现场和室内剪切波速的试验研究

利用安装在动三轴仪上的剪切波速测试装置 ,测试了天津某地区土的剪切波速 ,并在此基础上将室内测试结果与现场测试值进行了比较。研究发现二者的差值与土层埋深、粘粒含量等因素有直接关系     

基于空间注意力和卷积神经网络的视觉情感分析

为了解决现有基于深度学习方法的视觉情感分析忽略了图像各局部区域情感呈现的强度差异问题,提出一种结合空间注意力的卷积神经网络spatial attention with CNN, SA-CNN用于提升视觉情感分析效果。设计一个情感区域探测神经网络用于发现图像中诱发情感的局部区域;通过空间注意力机制对情感映射中各个位置赋予注意力权重,恰当抽取各区域的情感特征表示,从而有助于利用局部区域情感信息进行分类;整合局部区域特征和整体图像特征形成情感判别性视觉特征,并用于训练视觉情感的神经网络分类器。该方法在3个真实数据集TwitterⅠ、TwitterⅡ和Flickr上的情感分类准确率分别达到82.56%、80.23%、79.17%,证明利用好图像局部区域情感表达的差异性,能提升视觉情感分类效果。     

One-step strategy for synthesis of yolk–shell silica spheres using trisiloxane-tailed ionic liquids as a template

Yolk–shell silica spheres consisting of a core and an outer shell were prepared by a one-step method using a new class of eco-friendly templates, trisiloxane-tailed surface active ionic liquids. The effects of pH, calcination, and template concentration were investigated in detail. Our results showed that yolk–shell silica spheres could be obtained only in alkaline conditions when using trisiloxane-tailed ionic liquids as templates. The particle diameter, core diameter, dimension of void space, and shell thickness, which we measured by transmission electron microscopy and nitrogen adsorption–desorption techniques, could be tuned by precisely varying the template concentration. The organosilicon component of the ionic liquid template contributes to the reaction during the formation of yolk–shell nanostructures, which leads to a firm silica sphere skeleton resulting in essentially identical morphology and void structure before and after calcination. This investigation provides a convenient approach to fabricate yolk–shell silica spheres, which may expand the application of organosilicon ionic liquids in the field of nanomaterials and could be expected to generate tailor-made yolk–shell silica with functionality in both the core and shell.     

基于根轨迹法的核电厂棒位探测器电源PR控制的研究

针对单相逆变器在核电厂棒位检测系统中的应用要求,从数学模型出发分析了其控制策略,着重分析了输出电压环比例-谐振(PR)控制器在离散域的实现方式。通过Matlab仿真和实验验证了该控制方式能够保持输出电压稳定、正弦度良好、动态响应快、抗干扰能力强等特点,有利于提高棒位检测的精确度。     

碘氧铋光催化材料研究进展

近年来,针对碘氧化铋(BiOI)光催化材料改性的方法已经较为成熟,光催化能力得到了广泛的提升,但是BiOI光催化材料多为微纳米颗粒,回收和循环利用较困难,很容易引发二次污染.本文综述了对BiOI的改性方法以及在改性的同时提高循环利用性研究的现状,以便于后期方便工业化,并能有效地降低有机物光催化处理成本.     

2‐matrix‐based finite element linear solver for fast transient thermal analysis of high‐performance ICs

In this article, we propose ²‐based finite element (FE) solver for transient thermal analysis of high‐performance integrated circuits (ICs). ²‐matrix is a special subclass of hierarchical matrix or ‐matrix, which was shown to provide a data‐sparse way to approximate the matrices and their inverses with almost linear space and time complexities. In this work, we show that ²‐based mathematical framework can also be applied to FE‐based transient analysis of thermal parabolic partial differential equations. We show how the thermal matrix can be approximated by ²‐representations with controlled error. Then, we demonstrate that both storage and time complexities of the new solver are bounded by , where N is the matrix size. The method can be applied to any thermal structures for both steady and transient analysis. The numerical results from 3D ICs demonstrate the linear scalability of the proposed method in terms of both memory footprint and CPU time. The comparison with existing product‐quality LU solvers, CSPARSE and UMFPACK, on a number of 3D IC thermal matrices, shows that the new method is much more memory efficient than these methods, which however prevents the demonstration of the potential speedup of the proposed method over those methods. Copyright © 2014 John Wiley & Sons, Ltd.     

陆相储层非均质性及其对油藏采收率的影响—以冀东高尚堡和胜利永安镇油藏为例

储层非均质性主要包括层间非均质性、层内非均质性和平面非均质性。通过冀东和胜利等油藏开发研究表明,层间非均质性导致注水开发中主力小层的单层突进、主力层过早水淹、非主力层油气动用程度低和驱油效率低;层内非均质性控制和影响单砂层内注入剂波及体积,直接决定水驱效率,是影响层内剩余油分布的关键因素;平面非均质性直接影响到注入水波及面积和波及效率,从而控制剩余油在平面上的分布。为此采用了细分开发层系、分层注水、开展流动单元精细研究等地质和开发措施,可以有效地降低各类非均质性对油藏最终采收率的影响。