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胜利油田是一个以油气开采集输为主的综合性采油单位,每年油田的各种管道穿孔都较为严重。对油田生产直接造成了严重的经济损失和安全隐患。介绍了胜利油田目前生产上在用管道的现状及近三年来管道腐蚀穿孔情况,详细阐述了造成管道腐蚀穿孔的客观条件和主观因素,提出了相应的解决办法和对管道的保护措施,对以后日常生产中管道的施工和管理有一定的指导作用。 相似文献
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通过对双锅筒锅炉的结构分析,说明在以往进行的锅炉定期检验中,检验过程所采用的检查方法和内容,以及发现水冷壁管胀粗、裂纹、穿孔所进行的原因分析及处理方法。 相似文献
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Results of experiments on the high-speed perforation of different thicknesses of mild steel plate are presented, for impact velocities of up to 300 m/sec, and compared with the results of static perforation tests.Plate profiles, thinning of perforated plugs and energy requirements for perforation, are presented and discussed.It is found that the bulging of the target plate is greatest when the projectile is just contained, and that the bulging at containment increases with plate thickness over the early stages of the thickness range, after which it decreases with increasing plate thickness. This is contrary to the static case, in which the bulging continually increases. A photomicrograph of the material at the plug-plate interface is provided to support the view that thermo-plastic instability occurs when perforating thicker plates at high speed. 相似文献
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The paper describes a work focused on the process of perforation of aluminum sheet. A numerical investigation has been carried out to analyze in details the perforation process subjected to normal impact by different nose shapes of projectiles. The perforation process has been simulated by the application of 3D analysis using IMPACT dynamic FE program suite. The comparison on failure modes depending on the projectile nose shape have been studied and evaluated. An appropriate constitutive relation was applied to describe the material behavior of the aluminum sheet. The study covered different failure modes including petalling, plug ejection and circumference necking of perforated aluminum sheet according to different level of impact velocity ranging from 100 m/s to 600 m/s. In this investigation, a special attention will be given on the deformation and failure. 相似文献
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在石油开采过程中,射孔器材的改进和射孔工艺的改善对提高油田采收率和稳定油田产能具有重要意义。为评价射孔器材和射孔工艺的效能,在地面上建立了一套可对较深地层环境全模拟的高温超高压模拟井射孔试验装置。通过合理选用材料及结构设计,该装置能够模拟地下三维空间受压状态,进行多发弹射孔和流动性测试试验。文中对大直径超高压容器及其内部三腔压力分隔结构、温度和压力控制系统等作了介绍,对主要受压元件设计结构进行了强度、刚度的有限元分析计算。试验结果表明:该装置能够较好地模拟井下作业环境,为射孔效能评估分析研究提供了可靠的试验手段。 相似文献
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建立平纹编织面板蜂窝夹芯结构的渐进损伤分析模型来分别研究无损伤面板和单侧面板含穿孔损伤的蜂窝夹芯结构的侧向压缩性能,并将该结果与试验结果进行对照,以验证所建立模型的正确性。考虑到模型具有高度的材料非线性,选用ABAQUS/Explicit求解器进行蜂窝夹芯结构准静态侧向压缩性能的模拟,通过编写VUMAT子程序,分别设置面板和芯子的失效准则及刚度退化模型,选用内聚力模型模拟胶层,完成侧向压缩下蜂窝夹芯结构的渐进损伤分析。研究结果表明:无损伤面板的蜂窝夹芯结构侧向压缩强度受面板的屈曲行为控制,含穿孔损伤的蜂窝夹芯结构侧向压缩强度受含穿孔侧面板基体的抗压缩能力控制,且穿孔损伤会严重降低蜂窝夹芯结构的侧向压缩强度。 相似文献
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Malik M. Nazeer M. Afzal Khan Ather Naeem Anwar-ul Haq 《International Journal of Mechanical Sciences》2000,42(7):1391
The perforation of a ductile metal sheet with a conical tool is accompanied by elasto–plastic bending, stretching, plastic flow and perforation initiation and propagation and ultimately it results in material fracture in the form of petals. The number and size of petals depends on the sheet thickness, material properties, tool angle, anisotropy in the material and indentation speed. In this work the mathematical relations for the fracture mechanism has been developed to analyze different parameters’ response and evaluate fracture toughness of the metal sheets of various thickness using computer code based on this analysis. 相似文献
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Anthony N. van den Pol 《Journal of microscopy》1989,155(1):27-59
Colloidal gold is easily prepared, and readily adsorbs to a number of immunoreagents and other proteins for a wide variety of uses for neuronal visualization. Gold probes serve a role as immunolabels for both light and electron microscopy. As an ultrastructural immunocytochemical marker for detection of proteins, peptides or amino acids, gold can be used for immunostaining thick or thin sections prior to embedding, or for immunostaining ultrathin sections after embedding tissue in conventional or unusual embedding matrices. By virtue of its particulate nature, gold as an immunolabel facilitates a semi-quantitative analysis of relative antigen densities on ultrathin sections. Various combinations of different size gold particles or dual immunolabelling with enzymatic immunolabels together with colloidal gold or silver-intensified gold serve well for ultrastructural immunocytochemical localization of two antigens in the same tissue section. Colloidal gold can be detected with light microscopy, transmission and scanning electron microscopy, and with confocal laser microscopy. Silver intensification allows detection of gold at both the light and electron microscope level, and increases the sensitivity of immunogold procedures. Colloidal gold is useful as a tracer for physiological studies of transport and internalization in neurons in vivo and in vitro; computer-assisted video imaging techniques allow detection and tracking of single gold particles in living cells. 相似文献
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We propose a new technique for depositing a gold nanoparticle onto the tip of a dielectric support. We employed the photocatalytic effect of titanium dioxide for the deposition. When the titanium dioxide immersed in a solution including gold ions is subject to optical exposure, the excited electrons in the conduction band reduce gold ions into gold metal. Illumination by an evanescent wave generated with a total reflection configuration limits the deposition region to the very tip. In experiments we obtained 100–300 nm gold particles on SiN cantilever tips for atomic force microscopes. The contrast of evanescent interference fringes measured by a near-field scanning optical microscope with this gold nanoparticle probe has proved to be higher than that with a non-deposited SiN probe by a factor of 1.5. 相似文献
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Abstract Gold nanoparticles were synthesized by laser ablation of a gold metallic disc at wavelengths of 532 nm and 355 nm with 7 ns pulse duration in the pure water. The colloidal gold nanoparticles were characterized by ultraviolet-visible absorption spectroscopy, transmission electron microscopy, and fluorescence spectrometry. The presence of a surface plasmon resonance peak around ~ 524 nm indicates the formation of gold nanoparticles. The formation efficiencies of gold nanoparticles in colloids were found to increase when ablating the gold metallic disc with a laser having a longer wavelength. The size distributions of the gold nanoparticles thus produced were measured by transmission electron microscopy. A reduction in mean diameter of the particles was observed with a decrease in the laser wavelength under the irradiation at a high fluence of 25 mJ/pulse. The fluorescence spectroscopy demonstrated that these gold nanoparticles are fluorescent, showing a strong blue emission intensity at 458 nm. 相似文献
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Applications of gold cluster compounds in immunocytochemistry and correlative microscopy: comparison with colloidal gold 总被引:2,自引:0,他引:2
In this review, we discuss the immunocytochemical literature with respect to a comparison between conventional colloidal gold and gold cluster compounds as immunoprobes. The relative advantages and disadvantages of each of these types of particle for immunocytochemical applications are discussed. We present results from our own laboratories and those of others on the comparison of these immunoprobes in selected experimental situations. These results show the use of gold cluster compounds at both light and electron microscope levels. At the ultrastructural level, gold cluster compounds have been used in pre-embedding labelling of cultured cells, and for labelling of ultrathin cryosections and freeze-fracture preparations. Recently, fluorescently tagged gold cluster compounds have become available. Using ultrathin cryosections of human neutrophils as a model system, we demonstrate that a single immunoprobe (i.e. a fluorescently tagged gold cluster compound) is a robust probe for correlative fluorescence and electron microscopy. 相似文献
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《Wear》1986,108(2):169-184
Recent work on the graded interface between an ion-plated film and a substrate is discussed as well as the friction and wear properties of ionplated gold. X-ray photoelectron spectroscopy, depth profiling and microhardness measurements were used to investigate the interface. The friction and wear properties of ion-plated and vapor-deposited gold films were studied both in an ultrahigh vacuum system to maximize adhesion and in oil to minimize adhesion. The results of the investigation indicate that the solubility of gold in the substrate material controls the depth of the graded interface. Thermal and chemical diffusion mechanisms are thought to be involved in the formation of the Au-Ni interface. In the Fe-Au graded inter- face, gold was slightly dispersed in the iron and formed only a physically bonded interface. The hardness of the gold film was influenced by the thickness and was also related to the composition gradient between the gold and the substrate. A graded Ni-Au interface exhibited the highest hardness because of an alloy hardening effect. The effects of film thickness on adhesion and friction were established. A minimum coefficient of friction was found in the thin film region. No graded interfaces were detected in this investigation between vapor-deposited gold films and substrates. 相似文献
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本文制备了不同形貌的金纳米颗粒,并对其形貌对光学性能的影响进行了研究。本文用还原法制备了不同粒径的金纳米颗粒,采用晶种生长法成功地制备出了星形、梭形和棒状的金纳米颗粒。颗粒的形貌和大小并采用投射电子显微镜(TEM)进行了表征,结果说明,本文成功制备出了不同形貌大小的金纳米颗粒。UV-Vis光谱和拉曼光谱仪对制备的颗粒的表征测试说明,不同形貌大小对颗粒有着不同的光学性能。拉曼光谱的结果说明,不同形貌大小的金纳米颗粒可以用作不同浓度分子的探针,对物质进行检测。 相似文献
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Colloidal gold is a useful marker for functional‐imaging experiments in transmission X‐ray microscopy. Due to the low contrast of gold particles with small diameters it is necessary to develop a powerful algorithm to localize the single gold particles. The presented image‐analysis algorithm for identifying colloidal gold particles is based on the combination of a threshold with respect to the local absorption and shape discrimination, realized by fitting a Gaussian profile to the identified regions of interest. The shape discrimination provides the possibility of size‐selective identification and localization of single colloidal gold particles down to a diameter of 50 nm. The image‐analysis algorithm, therefore, has potential for localization studies of several proteins simultaneously and for localization of fiducial markers in X‐ray tomography. 相似文献
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通过对炉管的化学成分的测定以及对显微组织与水质的分析,找出了炉管发生腐蚀穿孔的原因并提出了防治措施. 相似文献