反凝析作用对苏里格气田上古生界气藏开发的影响

鄂尔多斯盆地苏里格气田上古生界气藏在开发中产生一定量的凝析油,含量约为10g/m~3,属于微含凝析油气藏,如果生产初期配产过大,那压力下降就会过快。在反凝析作用下,凝析油在近井地带析出形成多相流,堵塞微孔隙和吼道,导致气相渗透率降低,使得气井产量大幅下降,部分被封闭的天然气无法采出,层内凝析对储层的伤害有可能是永久性的。为此,通过对该气藏层内反凝析机理、层内凝析影响因素的分析及室内试验.再使用新建立的三维数学模型对单井进行预测,结果表明该气藏"三低"(低孔、低渗、低产)特征加剧了凝析液对储层的伤害。同时还分析了气井产能降低的根本原因.并对气井生产管理提出了建议:①在保护开采阶段,投产初期应合理配产,以低于无阻流量的1/5~1/8配产,尽可能延长露点线以上开采时间,使凝析油尽可能不在地层中析出;②在反凝析阶段,要在系统研究的基础上得出准确的相态图,要快速通过该阶段尽早进入蒸发阶段,使已经凝析出来的凝析油再次蒸发汽化,从而降低储层污染。该研究成果对苏里格气田上古生界气藏的科学开发以及进一步提高采收率具有重要意义。     

高铁接触网吊弦标定装备系统研究

针对高铁接触网吊弦标定施工机械化、智能化的作业要求,设计了一款吊弦标定施工装备,能够完成不同跨度吊弦安装位置的连续标定、接触网几何参数的自动测量.介绍了设备系统设计、系统组成、软件组成及外场功能试验等.试验数据表明:综合定位测距方案所有测试数据均小于±20 mm的定位精度要求,选取关键点腕臂定位器中心处接触线参数(导高和拉出值)检测数据误差均小于±5 mm,优于±10 mm的测量精度要求.     

大开孔焊制异径三通的安定载荷

风洞试验设备承受交变载荷的作用。文章采用理想弹塑性有限元法,借助ANSYS对试验设备中一承受交变载荷的大开孔焊制异径三通进行模拟计算,得到极限载荷。依据Melan定理,通过寻找修正一个与时间无关的自平衡应力场,推导结构处于安定状态下的应力分布状态并计算得到结构的安定载荷及安定因子。最后将安定载荷与标准数值进行比较,对大开孔异径三通的设计计算提供参考。     

Crystallization induced enhancement on electrical conductivity and strength of highly conductive PP composites

A highly conductive and reinforced polypropylene/nickel coated glass fiber (PP/NCGF) composite is fabricated via a simple and efficient strategy. Nucleating agent induced crystallization leads to the sharp volume excluded effect and drives NCGFs into the amorphous region of PP matrix, thus the formation of conductive network connected by NCGFs is promoted remarkably. The incorporation of nucleating agent dibenzylidene sorbitol (DBS) improves the strength of composites simultaneously due to the enhanced crystallinity and the reinforced interfacial interaction. Accordingly, the percolation threshold of PP/NCGF composites is decreased to 0.35 vol% (Ni content) by loading DBS, and the conductivity increases by four order of magnitude around the percolation threshold which exceeds 70 S/m with the Ni content of only 0.47 vol%. The tensile strength of PP/NCGF composites is increased by about 30–40 % in all range of NCGF content. This exciting result provides a strategy to prepare high-performance conductive composites by crystallization-induced enhancement.

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Graphical abstract Nucleating agent induced crystallization leads to the sharp volume excluded effect and drives Ni coated glass fibers into the amorphous region of PP matrix, thus the formation of conductive network is promoted remarkably. The incorporation of nucleating agent improves the strength of composites simultaneously due to the enhanced crystallinity and the reinforced interfacial interaction.

     

3D网状结构TiBw/Ti60复合材料高温力学性能

利用反应热压技术制备了3D网状结构Ti Bw/Ti60复合材料,对复合材料在600~750℃范围内的高温力学性能进行了测试。结果表明,与Ti60合金相比,3D网状结构Ti Bw的原位形成显著提高了复合材料高温强度。在600、650、700和750℃,5.1%(体积分数)Ti Bw/Ti60复合材料的抗拉强度相比Ti60合金分别提高了42.5%、39.9%、35%和13.2%,而延伸率在各温度下均低于基体合金。网状结构复合材料断裂时形成的主裂纹沿网状界面处扩展,且断裂机制随实验温度增加而改变。     

浅谈引气剂在混凝土中的应用

阐述了引气剂在混凝土中的作用机理以及影响混凝土含气量的因素，介绍了引气剂对新拌混凝土性能和硬化混凝土的耐久性、抗压强度、抗弯拉强度等性能的影响。     

Structure and properties of films fabricated from chitin solution by coagulating with heating

In the present work, chitin films were fabricated from chitin solution dissolved in 8 wt % NaOH/4 wt % urea aqueous systems at low temperature by coagulating with heating without using any coagulant. The formation of the chitin films was confirmed to be an entirely physical process, namely chitin inclusion complex associated with NaOH, urea and water in the solvent was broken by heating, leading to the aggregation of the chitin chains through the hydrogen bonding. A schematic model was proposed to describe the regeneration mechanism of the chitin, indicating the physical crosslinking and entanglement of the chitin chains to form the films. Glycerol was used as plasticizer, and with an increase of the glycerol content, the elongation at break (?_b) of chitin films increased rapidly from 7.8 to 83.1%, whereas the tensile strength (σ_b) decreased from 89.3 to 51.7 MPa. This work provided a “green” pathway for the researches and developments of chitin materials. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39538.     

High performance films of cellulose butyral derivative having a necklace-like annular structure in the side chains

We fabricated high performance films using cellulose butyral (CB) synthesized from native cellulose. Two-step reactions were adopted to produce the derivative CB, including etherification of cellulose with glycidol in NaOH/urea aqueous solution to yield O-(2,3-dihydroxypropyl) cellulose (DHPC), and butyralization of DHPC. Both DHPC and CB products were easily processed into a thin film by hot-press molding. The butyral modifier significantly improved the tenacity of highly ductile DHPC, by virtue of the possible chain-entangling action of the ring structures in the stretching process. Thereby the film toughness was markedly enhanced. The CB films exhibited excellent optical transparency and a good adhesive property to glass plates. Thus the films may be comparable to commercial poly(vinyl butyral) (PVB) films in optical and mechanical performances and therefore possess a potential applicability as interlayer for laminated glasses.     

延迟焦化装置辐射炉进料增加轻蜡油的技术改造分析

在对中石油西北某厂延迟焦化装置进行的扩能改造中,采用了辐射炉增加轻蜡油的工艺技术。改造结果说明,利用轻蜡油循环,改变辐射进料循环比,增产汽柴油收率并降低能耗,经济效益显著。     

烧结矿断面图像分析与操作指导系统

应用图像处理与神经网络技术,根据烧结操作人员对烧结矿FeO含量判断的方法,应用CCD摄像机采集烧结机尾断面图像对其进行实时处理、特征提取,并由根据烧结看火工的经验知识训练的BP神经网络对图像分类辨识,得出相应的FeO、燃料、水份等参数,应用人工智能方法指导生产操作.