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新型地铁有螺栓扣件及配套调高结构设计 被引量:2
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作者 韩朝霞 王书卫 《铁道建筑》 北大核心 2022年第6期58-62,共5页
针对地铁扣件应用过程中出现的弹条滑退、扣压力衰减、调高量不足等问题,提出了地铁新型有螺栓扣件及其配套调高结构的设计方案。新型扣件弹条与锚固螺栓垂直线路方向直列布置,铁垫板厚度适当减薄,铁垫板锚固螺栓孔及锚固螺栓平垫块设... 针对地铁扣件应用过程中出现的弹条滑退、扣压力衰减、调高量不足等问题,提出了地铁新型有螺栓扣件及其配套调高结构的设计方案。新型扣件弹条与锚固螺栓垂直线路方向直列布置,铁垫板厚度适当减薄,铁垫板锚固螺栓孔及锚固螺栓平垫块设置为锯齿形结构,以增大扣件调整量和保持轨距能力,铁垫板下采用厚度小刚度较大的橡塑垫板;通过对铁垫板的创新设计,形成了调高量20 mm和40 mm两种铁垫板,在满足安全稳定的前提下实现扣件的大调高量。同时对扣件铁垫板、螺栓等关键部件以及整体稳定性进行了力学检算,并进行了扣件试制及室内验证试验。结果表明:该新型扣件具有足够的强度、稳定性和耐久性,各零部件受力满足要求,结构设计合理;能够满足地铁的应用需求,且调高型扣件与普通型扣件零部件通用性好,养护维修方便。 展开更多
关键词 地铁 有螺栓扣件 结构设计 调高 调高结构
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Analysis of phospholipids in microalga Nitzschia closterium by UPLC-Q-TOF-MS 被引量:6
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作者 严小军 李海英 +1 位作者 徐继林 周成旭 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期106-112,共7页
Precise structural identification of phospholipids in the microalga Nitzschia closterium has been established using ultra performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectr... Precise structural identification of phospholipids in the microalga Nitzschia closterium has been established using ultra performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (UPLC-ESI-Q-TOF-MS) for direct analysis of total lipid extracts.Mass spectrometry was performed in reflective time-of-flight using electron spraying ionization in negative mode.Phospholipid molecular species identification was based on the characteristic product ions and neutral loss yielded by different phospholipids under ESI-MS/MS mode.The molecular species were confirmed by the carboxylate anions produced by phospholipids in negative mode;the regiospecificity of the two acyl chains was determined from the ratio of sn-1 to sn-2 carboxylate anion abundances.As a result,18 lipid molecular species were identified for the first time in this microalga,comprising seven phosphatidylcholines (PC),two phosphatidylethanolamines (PE),two phosphatidylinositols (PI),and seven phosphatidylglycerols (PG).Lipid standards of PC,PE,PI,and PG were added to the total lipids as internal standards for semiquantitative analysis,revealing concentrations of phospholipids in this species between 0.09 and 3.37 nmol/mg.This method can produce a full structural profile of intact phospholipid molecular species and can be used for study of the physiological and ecological functions of lipids by monitoring their individual changes over time. 展开更多
关键词 Nitzschia closterium PHOSPHOLIPIDS UPLC-Q-TOF-MS
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Solutions to Efficient Provision of Accommodations for Universities in China
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作者 张四平 《Journal of Chongqing University》 CAS 2002年第1期77-83,共7页
Chinese universities are facing a series of challenges in their accommodations, of which a predominant one is how to provide both students and staff with enough accommodations of a large scope and good quality in good... Chinese universities are facing a series of challenges in their accommodations, of which a predominant one is how to provide both students and staff with enough accommodations of a large scope and good quality in good time and with limited budgets. In order to find applicable approaches to solve this problem, the current situations of the Chinese higher education reform and the resulted rapid growth of student numbers whereby the requirement of lodgings is greatly increased are discussed. It is elucidated that in providing enough accommodations for staff and students, Chinese universities are confronted with difficulties including demand too big, lack of funding support, time limitation and incapability in both project management and facilities management. Industrialized building approach is demonstrated to be a desirable access to build large quantities of accommodations of good quality in limited time, and Private Financial Initiative (PFI) appears to be a prosperous solution to the fund shortage. Regarding project and facilities management, qualified professionals are available by either employing exterior consultants or training related staff of universities for such occupations. 展开更多
关键词 Higher education Construction ACCOMMODATION University reform
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调高支座技术的应用 被引量:1
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作者 赵雷 《科学中国人》 2014年第08S期28-28,共1页
介绍了桥梁建设中如何应用调高支座,并结合调高支座的构造特点及在工程中的应用介绍了调高结构的选择,调高工艺及调高前后支座性能的比较。
关键词 调高支座 调高结构 填充聚氨酯 调高试验
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Discussion on the Design Value of Environmental Condition in Offshore Structure Design
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作者 丁金鸿 谭家华 潘斌 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第4期456-461,共6页
Return period is generally adopted to calculate the design value of environmental condition in offshore structure design. However, it can not make relevant adjustment according to structure's, especially the mobile u... Return period is generally adopted to calculate the design value of environmental condition in offshore structure design. However, it can not make relevant adjustment according to structure's, especially the mobile unit's, life time or its operation areas and usually make the design either insufficiently safe or rather uneconomical. A formula is developed to solve this problem in the case of the design wave height, where the risk, the design life, the distributions of wave heights in operation areas and the operating durations in each area are regarded as parameters. The applications of this method and the comparisons with the general method are presented. The result of this method is considered to be proper. 展开更多
关键词 offshore structure design environmental condition design wave height
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