定面射孔套管结构动态响应分析及应用

定面射孔技术采用特殊的布弹方式,能在垂直于套管轴向同一横截面上形成多个射孔孔眼,改变井筒内同一横截面的井周地应力分布,制造射孔孔眼应力集中。它在造成地层应力集中和控制裂缝走向的同时也造成了套管局部应力集中,降低了套管的剩余强度。以解决定面射孔套管剩余强度评价和保障后续作业安全为目的,采用静力学分析、动力学响应仿真和试验测试相结合的方法,对定面射孔套管剩余强度综合分析研究,提出了以最大危险区域应力分布为依据的套管静力学剩余强度表达方法和以套管塑性应变区域体积与分布的套管结构剩余强度动力学响应表达方法,得到了不同参数下定面射孔的套管剩余强度。该技术的试验和应用为保障套管及井筒安全、大规模推广应用定面射孔技术奠定了坚实基础。     

木粉在超临界甲醇中的液化研究

以木粉和甲醇为原料,在高压反应釜中进行木粉在超临界甲醇中的液化分解反应,研究甲醇与木粉的配比、反应时间、反应压力、催化剂种类及用量对木粉分解率、气化率和液化率的影响。结果表明,以NaOH为催化剂,在甲醇与木粉质量比为4.5、反应温度为320℃、反应时间为1h的条件下,木粉液化率达到43.3%。     

Cell/surface interactions on laser micro-textured titanium-coated silicon surfaces

This paper examines the effects of nano-scale titanium coatings, and micro-groove/micro-grid patterns on cell/surface interactions on silicon surfaces. The nature of the cellular attachment and adhesion to the coated/uncoated micro-textured surfaces was elucidated by the visualization of the cells and relevant cytoskeletal & focal adhesion proteins through scanning electron microscopy and immunofluorescence staining. Increased cell spreading and proliferation rates are observed on surfaces with 50 nm thick Ti coatings. The micro-groove geometries have been shown to promote contact guidance, which leads to reduced scar tissue formation. In contrast, smooth surfaces result in random cell orientations and the increased possibility of scar tissue formation. Immunofluorescence cell staining experiments also reveal that the actin stress fibers are aligned along the groove dimensions, with discrete focal adhesions occurring along the ridges, within the grooves and at the ends of the cell extensions. The implications of the observed cell/surface interactions are discussed for possible applications of silicon in implantable biomedical systems.     

铝合金T形接头静止轴肩搅拌摩擦焊接及组织性能分析

成功实现了2219C10S铝合金T形接头的静止轴肩搅拌摩擦焊接,焊缝表面光滑平整,无明显减薄.从基板背部进行的超声相控阵检测结果表明,基板与肋板对合面全部焊透,接头内部无超标缺陷.接头横截面宏观金相可以观察到2个以肋板中心线对称分布的焊缝轮廓,单侧焊缝轮廓均超过了肋板中心线.接头横截面显微硬度分布趋势呈独特的“U”形,焊核区显微硬度最低.T形接头两个方向的拉伸试样起裂点位于“拉伸方向板材与接头R₁圆角的相切处”,但拉断试样断裂面的横穿区域存在较大差异,这也是沿肋板方向的抗拉强度比沿基板方向低20 MPa的主要原因.     

Zinc Accumulation and Behavior in Tuyere Coke

A case study of zinc oxide, which represents the first report on the occurrence, crystalline features, formation mechanism, and influence of this mineral in tuyere coke, was conducted in this study. A number of zinc oxides, some of which were in hexagonal wurtzite habit, were observed to distribute mainly in coke pores, cracks, surfaces, and around coke minerals. The accumulation of zinc in tuyere coke may enhance the degradation of coke and increase the generation and accumulation of coke fine in a blast furnace, which would cause bad effect on blast furnace operation. Investigations into zinc behavior in tuyere coke can be important for further interpretations of coke degradation in the high temperature zone of a blast furnace.     

基于智能算法的多机PSS参数协调优化

针对大规模电力多机系统考虑多种运行方式变化下的PSS参数协调优化问题,提出一种将遗传算法寻优和BP神经网络计算阻尼比结合的智能算法。该算法根据机组对振荡模态参与因子的大小选择需要优化的机组,采用遗传算法进行不同振荡模态及运行方式下最小阻尼比最大化的寻优,并以BP神经网络获得阻尼比的时域仿真过程。在经典的四机两区域系统上仿真表明,该算法寻优效果良好,具有较好的鲁棒性。     

不同弹性体对聚丙烯的协同增韧

以弹性体乙烯-α-辛烯共聚物(POE)、苯乙烯-乙烯/丁烯-苯乙烯共聚物(SEBS)和SEBS/POE作为增韧剂,对不同弹性体协同增韧聚丙烯进行了研究,考察了共混体系的力学性能、结晶行为、结晶形貌、动态力学分析以及低温脆断面形貌。结果表明,弹性体SEBS、POE均对PP具有增韧作用,当SEBS、POE用量分别为20%、25%时完成了"脆韧转变",其中SEBS增韧效果较佳;SEBS、POE作为弹性体加入,使PP的结晶度降低;当SEBS/POE复配增韧PP,且m(PP)/m(SEBS)/m(POE)=70/20/10时,具有协同增韧效应,冲击强度最高;此外,POE在PP/SEBS复配增韧中相当于相容剂,起到了"桥梁"作用。     

焦油切割泵固液两相流数值分析

分析了不同颗粒大小、转速及转子安放角度对切割泵内流线及固体颗粒分布的影响。结果表明,小流量时进口区域涡流严重,流量对固相浓度分布影响不大;颗粒和浓度越大,转子工作面固相浓度越高,对转子表面的磨损与冲蚀越严重;增大转速可以提高粉碎效率,但是对设备的使用寿命有影响。     

锂电池储能在风力发电系统中的应用

将锂电池储能系统应用到风力发电中,并针对锂电池储能系统的运行特性,提出了一种可行的综合控制策略。仿真结果表明,锂电池储能系统在电网正常运行时能够快速、有效地平滑风电系统输出的有功功率波动;在电网故障时能够为电网提供一定的无功支持;在脱离电网运行时能够稳定系统的电压和频率,有效地提高了风电系统的运行性能。     

无锡某会议中心地下工程防水施工工艺

无锡某会议中心地下工程采用了混凝土结构自防水和外贴BAC自粘防水卷材的防水设防方案.本文对自粘防水卷材在地下室基础底板和侧墙的不同施工工艺分别进行了阐述,并详细说明了桩头防水采用遇水膨胀止水条的施工技术.