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碳纤维布加固预应力混凝土吊车梁的设计方法 总被引:2,自引:1,他引:1
针对预应力混凝土吊车梁存在的问题,结合实际工作条件和结构所处的环境,对其提出初步处理方案。通过对初选方案对比和优选,并结合使用要求,确定采用粘贴碳纤维布方案对吊车梁实施加固。在详细介绍用碳纤维布加固鱼腹式T形截面预应力混凝土吊车梁的设计要点和方案的基础上,给出正截面受弯和斜截面受剪补强加固的计算方法,并提出相应的施工方法以及具体构造措施。加固处理后吊车梁的各项技术指标均达到了设计要求,效果良好。研究成果可为类似工程的应用提供理论和方法上的参考。 相似文献
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介绍了一种利用OLEAutomation技术通过Delphi编程来控制Excel ,实现Delphi数据集与Excel表格集成的方法 ,着重说明了运用面向对象的编程风格的建立新类 ,重载、扩充该类的成员 ,并给出了编程实例 相似文献
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Herein, macroporous carbon sheets (MCS) was synthesized by a re-assembly engineering. In this process, surfactant is combined with oligomeric resin to form micelles, which are re-assembled on the pre-prepared hybrid sheet through hydrogen bonding and electrostatic action, resulting in the reconstruction of relatively regular macropores on the sheet. The obtained MCS maintains the morphology of nanosheet with obvious circular macropores, high specific surface area and pore volume, which improves the charge transfer efficiency and is favorable electrochemical energy storage. As the electrode material for a supercapacitor, the MCS exhibits a high specific capacitance, excellent rate performance and long-term stability, which make the MCS an ideal electrode material for electrochemical energy storage. 相似文献
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Bhawani Narayan Satyaprasad P. Senanayak Ankit Jain K. S. Narayan Subi J. George 《Advanced functional materials》2013,23(24):3053-3060
Oligo(p‐phenylenevinylenes) (OPVs) with amphiphilic character are synthesized and their self‐assembly characteristics studied. Careful studies point at two morphologically different states of assemblies, with one being two dimensional sheets and the other as rolled tubes. This is also the first time that self‐assembled sheets are achieved for OPVs. Morphological and photo‐physical studies reveal a unique aggregate to aggregate transition between rolled tubes and two dimensional sheets, which is outlined as a more thermodynamic aggregate. The thermodynamic aggregate (2D sheet) is better ordered and consists of chromophores that are better excitonically coupled. The mobilities of these aggregates are also studied for a field effect transistor device and as expected sheets supersede rolled tubes by a couple of orders. More interestingly, the mobility values obtained for the well ordered chromophores in sheets is three orders higher than any other self‐assembled OPV previously reported. It is hypothesized that the better π interactions enforced by the amphiphilic design and the resultant supramolecular organization is a prime factor for such a remarkable rise in mobilities. 相似文献
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Y. ChandraR. Chowdhury F. ScarpaS. Adhikari J. SienzC. Arnold T. MurmuD. Bould 《Materials Science and Engineering: B》2012,177(3):303-310
This paper presents a multiscale approach for vibration frequency analysis of graphene/polymer composites. The graphene is modelled at the atomistic scale, and the matrix deformation is analysed by the continuum finite element method. Inter-connectivity between graphene and polymer matrix are assumed to be bonded by van der Waals interactions at the interface. The impact of geometrical configuration (armchair and zigzag), boundary conditions and length on the overall stiffness of the graphene reinforced plastics (GRP) is studied. The natural frequency and vibrational mode shapes of GRP studied have displayed dependence on the length and also the boundary conditions. The exceptional vibrational behaviour and large stiffness displayed by GRP makes them a potential replacement for conventional composite fibres such as carbon and glass fibres. 相似文献
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作为21世纪最具潜力的绿色金属材料,镁合金在航空航天、轨道交通、3C、纺织印刷、体育器材等领域得到越来越广泛的应用。本文研究了产业化生产的超宽镁合金中厚板和薄板的组织和性能,结果发现,通过调整热处理制度,可以获得再结晶等轴组织,中厚板性能可满足ASTMB90/B90M-2007标准要求,薄板性能可满足GBT5154—2010标准要求。 相似文献
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