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Numerical simulation on directional solidification of Al-Ni-Co alloy based on FEM

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China Foundry 2010年第1期7卷 57-60页

作者： yang zhili Chen Dengming Tian Shilong Liao Daohan yang Yu College of Metallurgy ＆ Material Engineering Chongqing University of Science and Technology Chongqing 401331 China

The ratio, of the temperature gradient at the solidification front to the solidification rate of solid-liquid interface, plays a large part in columnar grain growth. The transient temperature fields of directional solidification of Al-Ni-Co alloy were studied by employing a finite element method. The temperature gradient at the solidification front and the solidification rate were analyzed for molten steels pouring at different temperatures. The results show that with different initial pouring temperatures, the individual ratio of the temperature gradient at solidification front to the solidification rate soars up in the initial stage of solidification, then varies within 2,000-6,000 ℃.***2, and finally goes down rapidly and even tend to be closed to each other when the solidification thickness reaches 5-6 cm. The simulation result is consistent with the practical production which can provide an available reference for process optimization of directional solidified Al-Ni-Co alloy.

关键词： Al-Ni-Co alloy finite element method columnar grain transient temperature field directionalsolidification temperature gradient solidification rate

Distribution,Seismic Characteristics and Controlling Factors of Carbonate Platforms on the Northwestern Margin of the South China Sea

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 142-152页

作者： LI Lin WANG Bin yang Taotao yang zhili LI Li LU Yintao WANG Xuefeng WU Jingwu SUN Guozhong Petrochina Hangzhou Research Institute of Geology Hangzhou 310023China

Newly-acquired seismic data reveal widespread carbonate deposits covering a large part of the northwestern South China Sea *** carbonate platforms are identified to have developed on the topographic highs inherited from tectonic deformation and volcanic *** the carbonate platforms,the Miocene strata are characterized by high-amplitude seismic reflections and distinct platform architecture that overlaps older *** Guangle and Xisha carbonate platforms grew on faulted blocks due to South China Sea continental rifting,while the Zhongjian carbonate platform developed on a structural high induced by early Miocene *** the late Miocene,partial drowning resulted in the inhibition of platform growth,eventual platform drowning and termination of most carbonate *** drowning of the Guangle and Zhongjian carbonate platforms is shown by the supply of siliciclastic sediments during the late Miocene and seems to be closely linked to late Neogene volcanic activity,whilst the drowning of the Xisha carbonate platform is primarily related to relative eustatic *** results imply that tectonic activity,volcanism and eustasy are the dominant controls on the evolution of carbonate platforms on the northwestern margin of the South China Sea.

关键词： seismic characteristics carbonate deposition Guangle carbonate platform Xisha carbonate platform

A buried submarine canyon in the northwestern South China Sea: architecture, development processes and implications for hydrocarbon exploration

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Acta Oceanologica Sinica 2021年第2期40卷 29-41页

作者： Bin Wang Fuliang Lü Shuang Li Jian Li zhili yang Li Li Xuefeng Wang Yintao Lu Taotao yang Jingwu Wu Guozhong Sun Hongxia Ma Xiaoyong Xu Petrochina Hangzhou Research Institute of Geology Hangzhou 310023China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Ocean and Marginal Sea Geology Chinese Academy of SciencesGuangzhou 510301China Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510301China

High-resolution multichannel seismic data enables the discovery of a previous,undocumented submarine canyon(Huaguang Canyon)in the Qiongdongnan Basin,northwestern South China *** Huaguang Canyon with a NW orientation is 140 km in length,and 2.5 km to 5 km in width in its upper reach and 4.6 km to 9.5 km in width in its lower *** head of the Huaguang Canyon is close to the Xisha carbonate platform and its tail is adjacent to the Central *** buried submarine canyon is formed by gravity flows from the Xisha carbonate platform when the sea level dropped in the early stage of the late Miocene(around 10.5 Ma).The internal architecture of the Huaguang Canyon is mainly characterized by high amplitude reflections,indicating that this ancient submarine canyon was filled with coarse-grained *** sediment was principally scourced from the Xisha carbonate *** contrast to other buried large-scale submarine canyons(Central Canyon and Zhongjian Canyon)in the Qiongdongnan Basin,the Huaguang Canyon displays later formation time,smaller width and length,and single sediment *** coarse-grained deposits within the Huaguang Canyon provide a good environment for reserving oil and gas,and the muddy fillings in the Huaguang Canyon have been identified as regional ***,the Huaguang Canyon is a potential area for future hydrocarbon exploration in the northwestern South China *** result of this paper may contribute to a better understanding of the evolution of submarine canyons formed in carbonate environment.

关键词： South China Sea Qiongdongnan Basin submarine canyon evolution

A buried submarine canyon in the northwest South China Sea:architecture,development processes and implications for hydrocarbon exploration

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Acta Oceanologica Sinica 2021年第3期40卷 84-93页

作者： Bin Wang Fuliang Lyu Shuang Li Jian Li zhili yang Li Li Xuefeng Wang Yintao Lu Taotao yang Jingwu Wu Guozhong Sun Hongxia Ma Xiaoyong Xu Petrochina Hangzhou Research Institute of Geology Hangzhou 310023China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510301China

High-resolution multichannel seismic data enables the discovery of a previous,undocumented submarine canyon(Huaguang Canyon)in the Qiongdongnan Basin,northwest South China *** Huaguang Canyon with a NW orientation is 140 km in length,and 2.5 km to 5 km in width in its upper reach and 4.6 km to 9.5 km in width in its lower *** head of the Huaguang Canyon is close to the Xisha carbonate platform and its tail is adjacent to the central *** buried submarine canyon is formed by gravity flows from the Xisha carbonate platform when the sea level dropped in the early stage of the late Miocene(~10.5 Ma).The internal architecture of the Huaguang Canyon is mainly characterized by high amplitude reflections,indicating that this ancient submarine canyon was filled with coarse-grained *** sediment was principally scourced from the Xisha carbonate *** contrast to other buried large-scale submarine canyons(central canyon and Zhongjian Canyon)in the Qiongdongnan Basin,the Huaguang Canyon displays later formation time,smaller width and length,and single sediment *** coarse-grained deposits within Huaguang Canyon provide a good environment for reserving oil and gas,and the muddy fillings in Huaguang Canyon have been identified as regional ***,Huaguang Canyon is potential area for future hydrocarbon exploration in the northwest South China *** results may contribute to a better understanding of the evolution of submarine canyons formed in carbonate environment.

关键词： South China Sea Qiongdongnan Basin submarine canyon evolution

基于Kmeans++的自适应超像素投点方法

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半导体光电 2022年第3期43卷 585-591页

作者：杨志立张东武汉大学物理科学与技术学院微电子系武汉430072

超像素分割作为目标分割的预处理环节,能够极大地减少后续处理的数据量,对图像分割起着至关重要的作用。在大部分超像素生成算法中,初始种子点的选取都是以规则网格或随机确定,这容易导致欠分割。为了得到良好的初始种子点分布,减少种... 详细信息

超像素分割作为目标分割的预处理环节,能够极大地减少后续处理的数据量,对图像分割起着至关重要的作用。在大部分超像素生成算法中,初始种子点的选取都是以规则网格或随机确定,这容易导致欠分割。为了得到良好的初始种子点分布,减少种子点选取引起的欠分割,提出了一种基于Kmeans++的自适应确定超像素种子点方法,并由此改进了简单非迭代聚类算法(Simple Non-Iterative Clustering,SNIC)。实验结果表明,在不耗费大量计算成本的前提下,改进的SNIC算法相比传统算法能够得到更高的边界召回率和更低的欠分割错误率。

关键词：图像分割超像素 SLIC SNIC Kmeans++

中条山中生代镁铁质侵入岩年代学与地球化学:对华北克拉通南部岩石圈地幔性质的制约

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地球科学 2022年第4期47卷 1271-1294页

作者：刘洁袁玲玲杨智荔中南大学地球科学与信息物理学院有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院大学北京100049

镁铁质岩石作为幔源岩浆产物,其成因研究有助于探讨华北克拉通深部地幔性质及其演化过程.对中条山地区镁铁质侵入岩开展了系统的锆石U-Pb年代学、全岩主、微量元素、全岩Sr-Nd同位素和锆石Hf同位素研究,揭示了晚三叠世(217±2 Ma)和早... 详细信息

镁铁质岩石作为幔源岩浆产物,其成因研究有助于探讨华北克拉通深部地幔性质及其演化过程.对中条山地区镁铁质侵入岩开展了系统的锆石U-Pb年代学、全岩主、微量元素、全岩Sr-Nd同位素和锆石Hf同位素研究,揭示了晚三叠世(217±2 Ma)和早白垩世(121±2 Ma)两期镁铁质岩浆活动.晚三叠世镁铁质侵入岩SiO_(2)含量低至中等(46.03%~53.87%),MgO(14.37%~18.61%)、Ni(282×10^(-6)~433×10^(-6))、Cr(619×10^(-6)~1847×10^(-6))异常富集,亲岩浆元素丰度较低,上凸型稀土配分模式发育显著,指示岩体为堆晶成因.大量原生角闪石的发育表明晚三叠世杂岩的母岩浆高度富水,所有样品具有近平行的微量元素配分模式指示其轻度分异的LILE-HFSE(大离子亲石元素-高场强元素)组成反映地幔源区固有属性,母岩浆可能起源于经大洋板片沉积物熔/流体交代的地幔楔部分熔融.早白垩世镁铁质侵入岩SiO_(2)含量介于49.23%~54.99%,MgO和Fe_(2)O_(3) T含量分别为4.29%~7.17%和9.70%~14.79%,大离子亲石元素(Rb、Ba、K、Pb)和轻稀土元素富集,高场强元素(Nb、Ta、Zr、Hf、Ti)和重稀土元素亏损,可能为经俯冲陆壳衍生熔体交代的岩石圈地幔部分熔融形成.晚三叠世杂岩可能响应于扬子板块与华北克拉通碰撞引起的造山后岩石圈拆沉,早白垩世侵入岩则可能与古太平洋板块西向俯冲后回撤所引起的弧后岩石圈伸展有关.此外,二者均具有相对典型克拉通富集地幔亏损的全岩Nd(ε_(Nd)(t)=-18.56~-12.64)和锆石Hf(ε_(Hf)(t)=-20.2~+10.4),指示华北克拉通中南部岩石圈地幔性质自晚三叠世以来发生了显著改变,早白垩世克拉通破坏可能延及华北中部.

关键词：华北克拉通中条山镁铁质侵入岩岩石成因岩石圈地幔演化岩石学

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美国合同法上的口头证据规则

中南大学学报（社会科学版） 2015年第6期21卷 34-41页

作者：杨志利沈阳大学思政部辽宁沈阳110044

口头证据规则仅适用于整合合同确认之后,表明在整合合同之前或与之同时的口头证据不得与合同相抵触,也不得补充完全整合合同。口头证据规则排除了对事实的证明,是合同实体法规则,而不是证据法规则。口头证据规则的目的在于确定整合合同... 详细信息

口头证据规则仅适用于整合合同确认之后,表明在整合合同之前或与之同时的口头证据不得与合同相抵触,也不得补充完全整合合同。口头证据规则排除了对事实的证明,是合同实体法规则,而不是证据法规则。口头证据规则的目的在于确定整合合同中当事人意思的法律效力,它的适用限制是因为超出了它的目的范围。口头证据规则有利于激励当事人协商整合合同,有助于减少诉讼成本,我国民法典应予借鉴。

关键词：口头证据规则整合合同实体法合同解释

辽-蒙交界地区晚侏罗世高硅花岗岩:岩石成因与地质意义

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岩石学报 2021年第4期37卷 1061-1081页

作者：杨智荔张晓晖袁玲玲中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国科学院地球科学研究院北京100029 中国科学院大学北京100049 中南大学地球科学与信息物理学院有色金属成矿预测与地质环境监测教育部重点实验室长沙410083

高硅(SiO_(2)>70%)花岗岩不仅是指示大陆地壳成熟度的重要标志,而且蕴含大陆地壳分异机制和稀有金属元素运移行为的关键信息。跨越辽宁-内蒙古两地分布的白音花岩基是沿华北克拉通与中亚造山带边界断裂带侵位的重要的中生代高硅花岗岩,... 详细信息

高硅(SiO_(2)>70%)花岗岩不仅是指示大陆地壳成熟度的重要标志,而且蕴含大陆地壳分异机制和稀有金属元素运移行为的关键信息。跨越辽宁-内蒙古两地分布的白音花岩基是沿华北克拉通与中亚造山带边界断裂带侵位的重要的中生代高硅花岗岩,但其形成时代和岩石地球化学特征一直缺乏系统刻画。本次离子探针(SIMS)锆石U-Pb测年指示该花岗岩岩基于晚侏罗世(162~161Ma)侵位。岩体SiO_(2)含量介于75.7%~77.3%;钙碱性、贫铁镁、弱过铝;富集Th与U,亏损Ba与Sr;稀土元素总量较低(∑REE=40.2×10^(-6)~117×10^(-6)),Eu负异常明显;Zr/Hf和Nb/Ta分异显著;这些特征契合高分异I型花岗岩的典型元素地球化学行为。同时,白音花花岗岩具有低负的εNd(t)值(-3.5~-2.6)以及低正的锆石εHf(t)值(+0.1~+5.9)。元素与同位素地球化学示踪指示白音花花岗岩可能源自由中亚造山带型新生安山质地壳与少量古老地壳组成的复合源区,其部分熔融生成的原始酸性岩浆经历结晶分异形成高硅花岗岩。作为记录华北克拉通/中亚造山带边界断裂带晚侏罗世走滑/伸展活动的非造山型钉合岩体,白音花高硅花岗岩见证了蒙古-华北板块有别于早白垩世大规模上地壳伸展构造的中晚侏罗世区域弥散状中下地壳伸展行为。中晚侏罗世和早白垩世两段式地壳伸展轨迹不仅契合蒙古-鄂霍茨克构造域造山后重力垮塌过程,而且是促使新晋蒙古-华北板块大陆地壳垂向分异-成熟的高效途径。

关键词：晚侏罗世高硅花岗岩地球化学岩石成因钉合岩体华北克拉通

癌症相关成纤维细胞的异质性及其在靶向治疗中的应用

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中国肿瘤生物治疗杂志 2020年第12期27卷 1319-1327页

作者：闫廷杨治力上海交通大学附属第六人民医院甲乳疝外科上海200233

癌症相关成纤维细胞(cancer-associated fibroblasts,CAFs)是肿瘤微环境中最丰富和最关键的组成部分之一,不仅为肿瘤细胞提供物理支持,也在促进或延缓肿瘤发生发展方面起着关键作用。CAFs是一类高度丰富和异质性明显的间充质细胞系,包... 详细信息

癌症相关成纤维细胞(cancer-associated fibroblasts,CAFs)是肿瘤微环境中最丰富和最关键的组成部分之一,不仅为肿瘤细胞提供物理支持,也在促进或延缓肿瘤发生发展方面起着关键作用。CAFs是一类高度丰富和异质性明显的间充质细胞系,包含大量不同表型和功能的细胞亚群,针对其异质性的靶向治疗也应运而生。本文阐述CAFs来源、表型和功能相关的异质性,以及在靶向治疗中应用的研究进展,以期提高对恶性肿瘤中CAFs的认识。

关键词：肿瘤相关成纤维细胞肿瘤微环境异质性靶向治疗