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岩溶地质高速铁路特大桥桩基施工方法比选研究

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建筑技术开发 2025年第1期52卷 81-83页

作者：谭克亮济南轨道交通集团有限公司济南250100 济南交通发展投资有限公司济南250100

随着我国高速铁路工程的不断建设发展,在岩溶复杂地质跨越既有高速路桥桩基施工的情况越发频繁,其具有施工风险大、工期不易控制、造价成本高等特点。研究以新建济南至莱芜高速铁路工程章丘南跨京沪高速特大桥为工程依托,提出了岩溶地... 详细信息

随着我国高速铁路工程的不断建设发展,在岩溶复杂地质跨越既有高速路桥桩基施工的情况越发频繁,其具有施工风险大、工期不易控制、造价成本高等特点。研究以新建济南至莱芜高速铁路工程章丘南跨京沪高速特大桥为工程依托,提出了岩溶地质条件下片石粘土回填冲击成孔、全套管跟进旋挖钻成孔、超前注浆旋挖钻扩孔成孔3种桩基施工方法,通过在施工方法、施工工期、优劣势分析等方面进行比选分析,最终得出了最优施工方法。

关键词：高速铁路岩溶地质桩基施工方法比选

A global-local finite element analysis of hybrid composite-to-metal bolted connections used in aerospace engineering

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Journal of Central South University 2017年第6期24卷 1225-1232页

作者： liang ke Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China Faculty of Aerospace Engineering Delft University of TechnologyDelft 2629HSthe Netherlands

Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-dimensional(3D) stress variations is prohibitively expensive for a large-scale structure where hundreds of bolts can be present. In this work, the hybrid composite-to-metal bolted connections used in the upper stage of European Ariane 5ME rocket are analyzed using the global-local finite element(FE) approach which involves an approximate analysis of the whole structure followed by a detailed analysis of a significantly smaller region of interest. We calculate the Tsai-Wu failure index and the margin of safety using the stresses obtained from ABAQUS. We find that the composite part of a hybrid bolted connection is prone to failure compared to the metal part. We determine the bolt preload based on the clamp-up load calculated using a maximum preload to make the composite part safe. We conclude that the unsuitable bolt preload may cause the failure of the composite part due to the high stress concentration in the vicinity of the bolt. The global-local analysis provides an efficient computational tool for enhancing 3D stress analysis in the highly loaded region.

关键词： bolted connection global-local finite element approach failure bolt preload

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咪唑类化合物氧化脱氢催化剂研究进展

安徽化工 2025年第1期51卷 11-15,20页

作者：郭亮张科良西安石油大学化学化工学院陕西西安710065

咪唑类化合物作为一种重要的有机化学原料,在药物合成、功能离子液体、农业、缓蚀剂等领域的应用越来越广泛,近几年国内对其需求量不断增加,但是传统的咪唑工业合成工艺对环境污染较大,现环保政策的推行导致成本过高,企业面临着很大的... 详细信息

咪唑类化合物作为一种重要的有机化学原料,在药物合成、功能离子液体、农业、缓蚀剂等领域的应用越来越广泛,近几年国内对其需求量不断增加,但是传统的咪唑工业合成工艺对环境污染较大,现环保政策的推行导致成本过高,企业面临着很大的生产压力。将咪唑啉类化合物催化氧化合成咪唑类化合物不需要高污染的原料,反应过程简单环保,有望改变这一现状,寻求催化性能良好、绿色、经济的催化剂是其中重点。主要从贵金属和非贵金属催化剂两大类介绍总结了现有的国内外咪唑类化合物氧化脱氢催化剂,综合其反应时间、温度、用量等因素做出评价,并对催化剂的未来发展和改进做出了展望。

关键词：咪唑氧化脱氢咪唑啉催化剂贵金属

Interface characteristics and wear resistance of Ni-B_(4)C plated ZTA reinforced high chromium cast iron composite

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China Foundry 2023年第3期20卷 253-262页

作者： ke-liang Li Wei Li Yan-liang Yi Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China National Joint Engineering Research Center of High Performance Metal Wear Resistant Materials Technology Jinan UniversityGuangzhou 510632China

A chemical composite plating of Ni-B_(4)C was used to prepare the surface-modified zirconia toughened alumina(ZTA)ceramic *** ceramic preforms were prepared by the plated ZTA and sodium silicate solution binder,followed by casting infiltration to prepare the ZTA particles reinforced high chromium cast iron(HCCI)*** result reveals that a distinct interface layer forms at the ZTA/HCCI interface,which consists of phases of ZrB_(2),FeB,Fe_(2)B,and NaSiO_(4).The interfacial wettability between ZTA and HCCI is improved by the diffusion and reaction of Ni and B_(4)*** wear test reveals that the Ni-B_(4)C plated ZTA particles can effectively improve the wear resistance of the ZTA/HCCI composite,and the wear rate of the composite is decreased to 11.6%of HCCI.

关键词： ZTA composite high chromium cast iron interface layer three-body abrasive wear

A Class of Homogeneous Einstein Manifolds

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Chinese Annals of Mathematics,Series B 2006年第4期27卷 411-418页

作者： Yifang KANG ke liang Department of Mathematics Tianjin University Tianjin 300072 China School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China.

A Riemannian manifold （M, g） is called Einstein manifold if its Ricci tensor satisfies r=c.g for some constant c. General existence results are hard to obtain, e.g., it is as yet unknown whether every compact manifold admits an Einstein metric. A natural approach is to impose additional homogeneous assumptions. M. Y. Wang and W. Ziller have got some results on compact homogeneous space G/H. They investigate standard homogeneous metrics, the metric induced by Killing form on G/H, and get some classification results. In this paper some more general homogeneous metrics on some homogeneous space G/H are studies, and a necessary and sufficient condition for this metric to be Einstein is given. The authors also give some examples of Einstein manifolds with non-standard homogeneous metrics.

关键词： Einstein manifold Homogeneous space General homogeneous metric

Sheets and rigid orbit covers of exceptional Lie groups

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Chinese Science Bulletin 1998年第20期43卷 1702-1707页

作者： ke liang Linyuan Lu Nankai Univ Dept Math Tianjin 300071 Peoples R China

All sheets of exceptional Lie groups by the geometric calculating method are given. The conjecture that the sheets of an exceptional Lie group are disjoint on the basis of the calculating result is proved.

关键词： Lie group orbit sheet.

Induced orbit data and induced unitary representations for complex groups

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Science China Mathematics 2014年第7期57卷 1435-1442页

作者： ZHANG MingJing liang ke School of Mathematical Sciences Nankai University The key Laboratory of Pure Mathematics and Combinatorics Nankai University

We use induced orbit covers to define induced orbit *** studying the space of regular functions on orbit cover,we know that the induced representation has close connection with the induced orbit datum under the meanin... 详细信息

关键词： Vogan’s conjecture on quantization induced orbit covers induced orbit data unitary representations

Dependence of low redshift Type Ia Supernovae luminosities on host galaxies

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Research in Astronomy and Astrophysics 2013年第9期13卷 1087-1096页

作者： Wen-ke liang Jian-Cheng Wang National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We study the relation between Type Ia Supernovae （SNe Ia） and properties of their host galaxies using a large sample with low redshift. By examining the Hubble residuals of the entire sample from the best-fit cosmology, we show that SNe Ia in passive hosts are brighter than those in star-forming hosts after light curve correction at the 2. 1σ confidence level. We find that SNe Ia in high luminosity hosts are brighter after light-curve correction at the 〉 3σ confidence level. We also find that SNe Ia in large galaxies are brighter after light-curve correction at the ≥2σ confidence level. We demonstrate that the residuals depend linearly on host luminosity at a confidence of 4or or host size at a confidence of 3.3σ.

关键词： supernovae: general -- distance scale -- galaxies: classification

Homogeneous manifolds admitting non-Riemannian Einstein-Randers metrics

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Science China Mathematics 2015年第7期58卷 1473-1482页

作者： CHEN ZhiQi DENG ShaoQiang liang ke School of Mathematical Sciences and LPMC Nankai University

In this paper, we find some new homogeneous manifolds G/H admitting non-Riemannian EinsteinRanders metrics when G is the compact simple Lie group E6, or E7 or E8. In the beginning, we prove that these homogeneous manifolds admit Riemannian Einstein metrics. Based on these metrics, we obtain non-Riemannian Einstein Randers metrics on them.

关键词： Einstein metrics Randers metrics homogeneous manifolds