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磁铁矿和磁赤铁矿磁化率的温度和频率特性及其环境磁学意义

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第四纪研究 2007年第6期27卷 955-962页

作者：刘青松邓成龙潘永信 National Oceanography Centre University of SouthamptonSouthampton SO143ZHUK 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

磁化率随温度和频率的变化特性(F-T)对于研究超顺磁和单畴磁性颗粒的磁学性质非常有效。文章结合饱和磁化强度和矫顽力随温度变化的特性,依据尼尔理论,探讨了磁性颗粒的粒径分布与其(F-T)特性的关系。结果表明,磁化率的最大值对应于其... 详细信息

磁化率随温度和频率的变化特性(F-T)对于研究超顺磁和单畴磁性颗粒的磁学性质非常有效。文章结合饱和磁化强度和矫顽力随温度变化的特性,依据尼尔理论,探讨了磁性颗粒的粒径分布与其(F-T)特性的关系。结果表明,磁化率的最大值对应于其解阻温度,因此可以用来估算磁性颗粒的平均粒径。随温度变化的频率磁化率曲线可以转化为连续的粒径分布曲线。本方法可以用来模拟自然地质体(例如,火山灰、黄土沉积物)中磁性矿物的粒度分布。

关键词：磁化率岩石磁学环境磁学磁化率的温度和频率特性

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月壤样品(E21)磁学性质及古强度研究

岩石学报 2022年第6期38卷 1832-1842页

作者：蔡书慧秦华峰邓成龙刘双迟陈意贺怀宇潘永信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 中国科学院大学地球与行星科学学院北京100049 中国科学院地质与地球物理研究所地球与行星物理院重点实验室北京100029

本文对中国科学院地质与地球物理研究所馆藏月壤样品(E21)中的5颗毫米级月壤岩屑(2颗胶结物、1颗角砾岩、2颗玄武岩)开展了详细的矿物学、岩石磁学和古强度研究。扫描电镜结果显示月壤岩屑主要矿物成分为钛铁矿、辉石、斜长石、陨硫铁等... 详细信息

本文对中国科学院地质与地球物理研究所馆藏月壤样品(E21)中的5颗毫米级月壤岩屑(2颗胶结物、1颗角砾岩、2颗玄武岩)开展了详细的矿物学、岩石磁学和古强度研究。扫描电镜结果显示月壤岩屑主要矿物成分为钛铁矿、辉石、斜长石、陨硫铁等,主要载磁矿物为铁镍合金。岩石磁学结果显示胶结物/角砾岩与玄武岩岩屑磁学性质存在明显差异,前者比后者载磁能力更强。古强度结果显示月壤岩屑记录了较强的古强度值,验证了月壤岩屑记录古磁场的能力。本研究获得的岩石磁学和古强度结果与已发表阿波罗样品结果相吻合,证实了月壤磁学研究方法和技术的有效性,也为判断馆藏月壤样品来源提供了磁学信息约束。本文对阿波罗月壤岩屑开展的磁学研究及获得的系列认识,为开展嫦娥五号返回样品磁学研究积累了经验。

关键词：阿波罗样品月壤岩屑磁学性质古强度

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四边曲面重建中的边界优化算法

计算机工程与应用 2004年第12期40卷 55-57页

作者：潘永信张树有浙江大学机械工程系杭州310027

文中针对Floater“保形参数化”方法存在的局限性,研究了四边曲面重建中,边界曲折程度的评定方法。通过比较边界上网格点的曲率值,构造形式上的四边拓扑曲面;通过对边界网格的优化剖分,获得相对平滑的边界曲线。与Floater算法相比,提出... 详细信息

文中针对Floater“保形参数化”方法存在的局限性,研究了四边曲面重建中,边界曲折程度的评定方法。通过比较边界上网格点的曲率值,构造形式上的四边拓扑曲面;通过对边界网格的优化剖分,获得相对平滑的边界曲线。与Floater算法相比,提出了曲折边界的平滑剖分方法,改善了重建曲面边界上的扭曲变形,为Floater重建算法在工程CAD模型中的推广提供了实用途径。

关键词：曲面重建参数化三角剖分参数映射

Low-temperature magnetic properties of horse spleen ferritin

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Chinese Science Bulletin 2010年第27期55卷 3174-3180页

作者： TIAN LanXiang 1,2,CAO ChangQian 1,2,LIU QingSong 1,2 &pan yongxin 1,2 1Key Laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2Franco-Chinese Biomineralization and Nano-structures Laboratory,Beijing 100029,China Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Franco-Chinese Biomineralization and Nano-structures Laboratory Beijing China

The magnetic properties of the antiferromagnetic cores in ferritin are of importance in the construction and improvement of ferritin-based magnetic resonance imaging systems and their application to environmental *** this study,we carry out integrated magnetic and transmission electron microscopy analyses of horse spleen ferritin(HoSF)to understand the relationships between the magnetic behavior of HoSF and temperature,applied field and grain-size *** R-value from the Wohlfarth-Cisowski test for the investigated sample at 5 K was 0.46,indicating very weak magnetostatic interactions among the nanoparticles of *** nanoparticles of HoSF show superparamagnetic properties at room temperature,while below the blocking temperature of Tb≈12 K it has a net magnetic moment that comes from the uncompensated spins of the nanoparticle surface or *** thermal relaxation process of HoSF follows the Néel-Arrhenius *** low-temperature AC susceptibility data,we calculated the effective magnetic anisotropy energy Ea=(5.52±0.16)×10-21 J;the effective magnetic anisotropy energy constant Keff=(4.65±0.14)×10 4 J/m3 and the pre-exponential frequency factor f0 =(4.52±2.93)×1011 *** values are useful in understanding the magnetic behavior of the antiferromagnetic nanoparticles and their potential application in biomedical technology.

关键词：马脾铁蛋白低温度磁性质透射电子显微镜磁各向异性常数纳米粒子生物医学技术交流磁化率

Paleomagnetism and the Earth＇s deep interior： unsolved problems and future challenges

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Episodes 2007年第3期30卷 227-227页

作者： Rixiang Zhu Keke Zhang yongxin pan Director Institute of Geology & Geophysics State Key Laboratory of Lithospheric Evolution Chinese Academy of Sciences Beijing 100029 CHINA Director Centre for Geophysical and Astrophysical Fluid Dynamics University of Exeter Exeter EX4 4QE UK Paleomagnetism and Geochronology Laboratory Institute of Geology & Geophysics Chinese Academy of Sciences Beijing 100029 CHINA

Nearly a hundred scientists and researchers from across the world, including China, France, Germany, Holland, Japan, Korea, Spain, UK, and USA, gathered at the Insti- tute of Geology and Geophysics, Beijing, for a threeday symposium on Paleomagnetism and the Earth＇s Deep Interior. The symposium was co-sponsored by the National Natural Science Foundation of China and the Chinese Academy of Sciences, and was co- organized by Professor R. Zhu, Beijing, China and Professor K. Zhang, Exeter, UK.

关键词：古磁学地球内部结构科学研究

Targeted In Vivo Imaging of Microscopic Tumors with Ferritin-based Nanoprobes Across Biological Barriers

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Targeted In Vivo Imaging of Microscopic Tumors with Ferritin...

Timing of the Nihewan formation and faunas

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Changqian Cao Xuxia Wang Yao Cai Lei Sun Lanxiang Tian Hao Wu Xiaoqing He Hao Lei Weifeng Liu Guanjun Chen Rixiang Zhu yongxin pan Franco-Chinese Bio-Mineralization and Nano-Structures Laboratory Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Wuhan Center for Magnetic Resonance State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics & Mathematics Chinese Academy of Sciences Center for Biological Imaging Institute of Biophysics Chinese Academy of Sciences State Key Laboratory of Microbial Technology School of Life Sciences Shandong University

One of the major obstacles in clinical cancer intervention is the in vivo detection of tumors at early stages,when the cancer is still confi ned to the site of origin and timely preventative treatment is possible.[1,2]Advances in nanoparticle-based molecular imaging have greatly enhanced the sensitivity and specifi city of imaging modalities for tumor *** particular,nanoparticles functionalized with ligands specifi c for overexpressed

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Timing of the Nihewan formation and faunas

An ancient origin of bacterial magnetic navigation and biomineralization

中国科学院地质与地球物理研究所2008学术年会

作者： Chenglong Deng~*,Rixiang Zhu,Rui Zhang,Hong Ao,yongxin pan Paleomagnetism and Geochronology Laboratory(SKL-LE),Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

Magnetostratigraphic dating of the fluvio-lacustrine sequence in the Nihewan Basin,North China,has permitted the precise timing of the basi(?) infilling and associated Nihewan mammalian *** combined evidence of new paleomagnetic findings from the Hongya and Huabaogo(?) sections of the eastern Nihewan Basin and previously published magnetochronological data suggests that the Nihewan Formation records the tectono-sedimentary processes of the Plio-Pleistocene Nihewan Basin and that the Nihewan faunas can be placed between the Matuyama-Brunhe(?) geomagnetic reversal and the onset of the Olduvai subchron(0.78-1.95 Ma).The onset and termination of the basin deposition occurred just prior t(?) the Gauss-Matuyama geomagnetic reversal and during the period from the last interglaciation to the late last glaciation,respectively,suggesting tha the Nihewan Formation is of Late Pliocene to late Pleistocene *** Nihewan faunas,comprising a series of mammalian faunas(such as Maliang Donggutuo,Xiaochangliang,Banshan,Majuangou,Huabaogou,Xiashagou,Danangou and Dongyaozitou),are suggested to span a time range o about 0.8-2.0 *** combination of our new and previously published magnetostratigraphy has significantly refined the chronology of the terrestrial Nihewan Formation and faunas.

关键词： Magnetostratigraphy Magnetochronology Nihewan Basin Nihewan Formation Nihewan faunas

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Science Foundation in China 2017年第3期25卷 25-25页

作者： Lin Wei (林巍) pan yongxin (潘永信) Institute of Geology and Geophysics Chinese Academy of Sciences

Subject Code:D04With the support by the National Natural Science Foundation of China,*** Wei(林巍),*** yongxin(潘永信)and co-workers from the Institute of Geology and Geophysics,Chinese Academy of Sciences and a team ... 详细信息

关键词： An ancient origin of bacterial magnetic navigation and biomineralization

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中国黄土环境磁学

第四纪研究 2007年第2期27卷 193-209页

作者：邓成龙刘青松潘永信朱日祥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 National Oceanography Centre University of SouthamptonSouthampton SO14 3ZH UK

中国陆相风成沉积序列蕴含了晚新生代以来丰富的古地磁场和古气候信息。第四纪黄土-古土壤序列的岩石磁学性质可以揭示第四纪亚洲内陆地区干旱化过程和东亚古季风演化历史以及末次冰期-间冰期旋回的气候不稳定性特征。文章主要评述近年... 详细信息

中国陆相风成沉积序列蕴含了晚新生代以来丰富的古地磁场和古气候信息。第四纪黄土-古土壤序列的岩石磁学性质可以揭示第四纪亚洲内陆地区干旱化过程和东亚古季风演化历史以及末次冰期-间冰期旋回的气候不稳定性特征。文章主要评述近年来中国黄土环境磁学研究所取得的一系列重要进展,同时提出目前需要深入研究的几个重要问题,如成土作用对黄土沉积物沉积剩磁的影响、微生物对磁性矿物的改造、亚洲内陆地区气候过程和环境演变的磁气候学记录等。

关键词：中国黄土环境磁学岩石磁学磁气候学