海河隧道工程防洪影响分析

海河隧道线路全长2 3034 m,其中主河道沉管段长240 m,沉管断面宽度374 m,高98 m,共设置两节,每节120 m。河道沉管段采用水中沉管法施工。管段安装会对河道的防洪安全产生较大的影响,故须对河段的水沙条件有严格的要求。本文采用三维分层水流泥沙数学模型,通过错层处理,较好地解决了同层网格产生急剧变化,在突变点处隔层网格物理量的影响远大于层间网格的影响问题。对隧道管段悬浮状态、沉放过程中的过流能力、水流流态和河段水流泥沙运移规律进行了深入分析,提出管段对河段水沙的影响程度及解决措施。本研究拓展了三维分层水流泥沙数学模型的应用范围,为保证工程施工安全提供了理论基础。     

应力吸收层沥青混合料的半圆弯拉试验参数

针对应力吸收层组成材料及结构受力的特殊性,探索一种与之相匹配的低温抗裂性能的评价方法具有重要意义。在比较分析已有的沥青混合料低温抗裂试验方法的基础上,得出半圆弯拉试验方法用于评价应力吸收层混合料低温性能的合理性及优越性。采用三维有限元方法,建立带缺口的半圆弯拉试验模型,进行各试验参数下的应力分析。结果表明:试件的最佳厚度为50mm,底部拉应力基本上趋于稳定,受外部影响不大;随缺口宽度的增加,缺口处底部拉应力逐渐减少,基本上成线性关系,缺口宽度的最佳尺寸1.5mm;随缺口深度的增加,缺口处底部拉应力逐渐增大,在小于20mm时成线性增加,支座间距宜为0.8倍试件直径。     

松辽盆地榆树林油田葡萄花油层储层特征

文章在系统收集和整理榆树林油田葡萄花油层资料的基础上,利用薄片观察和统计、扫描电镜观察分析、岩石物性(孔、渗)测定及压汞资料分析等方法,重点对葡萄花油层储层内岩石矿物成分、成岩作用类型、孔隙类型及孔隙结构特征进行了详细研究,为指导油气开发提供科学依据。研究表明:榆树林油田葡萄花油层为中孔、中渗储层,岩石以长石砂岩为主,具有结构成熟度中等,成分成熟度较低的特点;储集空间以残余粒间孔为主,亦见有次生溶蚀孔及晶间微孔;根据孔隙结构特征,将葡萄花油层储层分成4类。     

Basic properties of free stratified flows

Results of analytical studies of the governing equations of stratified rotating fluids based on the unification of theories of continuous and discrete groups, perturbations and modern numerical visualizations are described. Symmetries of basic systems and their simplified versions, different approximations and constitutive turbulent models are compared. A new method to calculate discrete groups analytically, which does not need a preliminary search for continuous groups, is developed. As an example of the practical use of the developed algorithm, a complete classification of cellular and roll structures of Bénard convection is presented. A complete classification of 3D periodic motions in compressible viscous stratified and rotating fluids, including regular (wave) and singular elements, is performed by perturbation methods. In all cases, in a viscous fluid, besides waves there are two different periodic boundary layers. In a homogeneous fluid the split boundary layers are merged, thus forming a joint doubly-degenerate structure. Stratification and rotation reduce the degeneration of the 3D periodic boundary layers. Calculations of a 3D periodic wave beam emitted by an oscillating part of a sloping plane are visualized by a computer-graphics method. The existence of thin extended components on the edges of the 3D wave cone is demonstrated.     

Alteration of internal stresses in SiO2/Cu/TiN thin films by X-ray and synchrotron radiation due to heat treatment

A break of wiring by stress-migration becomes a problem with an integrated circuit such as LSI. The present study investigates residual stress in SiO₂/Cu/TiN film deposited on glass substrates. A TiN layer, as an undercoat, was first deposited on the substrate by arc ion plating and then Cu and SiO₂ layers were deposited by plasma coating. The crystal structure and the residual stress in the deposited multi-layer film were investigated using in-lab. X-ray equipment and a synchrotron radiation device that emits ultra-high-intensity X-rays. It was found that the SiO₂ film was amorphous and both the Cu and TiN films had a strong {1 1 1} orientation. The Cu and TiN layers in the multi thick (Cu and TiN:1.0 μm)-layer film and multi thin (0.1 μm)-layer film exhibited tensile residual stresses. Both tensile residual stresses in the multi thin-layer film are larger than the multi thick-layer film. After annealing at 400 °C, these tensile residual stresses in both the films increased with increasing the annealing temperature. Surface swelling formations, such as bubbles were observed in the multi thick-layer film. However, in the case of the multi thin-layer films, there was no change in the surface morphology following heat-treatment.     

土工格栅与铜矿尾矿界面作用特性的实验研究

钢塑复合土工格栅的加筋效果好于其它筋材的原因在于其表面结构特性,在生产过程中塑料表面处理时,肋条压制成粗糙的花纹,以增强格栅表面的粗糙程度,提高CATT钢塑复合土工格栅与土体的摩擦系数。它与土之间不仅存在表面摩擦力,而且还存在镶嵌咬合力,从而增强加筋土体的稳定性。文中以不同规格的钢塑复合土工格栅作为加筋材料,以有色金属铜矿的尾矿作为填料土,通过拉拔实验,研究钢塑复合土工格栅与铜矿尾矿填料土的界面作用特性,获得了筋--土之间的剪切强度系数(C、φ)、似摩擦系数f*等结果,并对它们的影响因素进行了分析与探讨。     

Epitaxial Growth of CeO<Subscript>2</Subscript>/YSZ/CeO<Subscript>2</Subscript> Buffer Layers on Textured Ni Substrates for YBCO Conductors

CeO₂/YSZ/CeO₂ buffer layers were deposited on textured Ni substrates byin situ pulsed laser deposition. The out-of-plane texture and in-plane texture of the buffer layers were characterized by X-ray diffraction ω-scans and ϕ-scans. Using this CeO₂/YSZ/CeO₂ architecture as the buffer layers, high quality YBCO films with a zero-resistanceT _c about 90 K and a self-field critical current densitiesJ _c above 10⁶ A/cm² at 77 K can be obtained on Ni substrates.     

STRATA应力吸收层抗疲劳特性研究

通过柔性道面足尺试验对旧水泥混凝土路面上3种不同加铺层结构进行了裂缝开展的温度疲劳特性研究。结果表明，旧水泥混凝土路面 STRATA应力吸收层 沥青混凝土的路面结构形式具有优良的抗温度疲劳反射裂缝的能力。