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Chinese Physics B 2018年第8期27卷 529-534页

作者： Yu-Qing Li Ming Yue yi pen.Hong-Guo Zhang College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

In this study, micromagnetism simulation by using timte dltterence method is cameo out on the Ncl21-el415/a-Fe nanocomposite magnet with soft phase imbedded in hard phase. The effects of soft magnetic phase size （S） on the magnetic properties and magnetic reversal modes are systematically analyzed. As S increases from 1 nm to 48 nm, the remanence （Jr） increases, while the coercivity （Hci） decreases, leading to the result that the magnetic energy prod- uct [（BH）max] first increases slowly, and then decreases rapidly, peaking at S = 24 nm with the （BH）max of 72.9 MGOe （1 MGOe = 7.95775 kJ.m-3）. Besides, with the increase of S, the coercivity mechanism of the nanocomposite magnet changes from nucleation to pinning. Furthermore, by observing the magnetic moment evolution in demagnetization pro- cess, the magnetic reversal of the soft phase in the nanocomposite magnet can be divided into three modes with the increase of S： coherent rotation （S 〈 3 nm）, quasi-coherent rotation （3 nm≤S 〈 36 nm）, and the vortex-like rotation （S ≥36 nm）.

关键词： micromagnetism simulation magnetization dynamics, Nd2Fe14B/a-Fe nanocomposite magnets

Formation of active oxygen species on single-atom Pt catalyst and promoted catalytic oxidation of toluene

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Nano Research 2020年第6期13卷 1544-1551页

作者： Shunzheng Zhao Yanfeng Wen Xijun Liu Xianyun pen.Fang Lü Fengyu Gao Xizhou Xie Chengcheng Du Honghong yi Dongjuan Kang Xiaolong Tang Department of Environmental Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing100083China Center for Electron Microscopy and Tianjin Key Lab of Advanced Functional Porous Materials Institute for New Energy Materials&Low-Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin300384China

Catalytic oxidation of toluene over noble metal catalysts is a representative reaction for elimination of volatile organic compounds(VOCs).However,to fully understand the activation of molecular oxygen and the role of active oxygen species generated in this reaction is still a challenging ***,MgO nanosheets and single-atom Pt loaded MgO(Pt SA/MgO)nanosheets were synthesized and used as catalysts in toluene *** activation process of molecular oxygen and oxidation performance on the two catalysts were contrastively *** Pt SA/MgO exhibited significantly enhanced catalytic activity compared to *** oxygen vacancies can be easily generated on the Pt SA/MgO surface,which facilitate the activation of molecular oxygen and the formation of active oxygen *** on the experimental data and theoretical calculations,an active oxygen species promoted oxidation mechanism for toluene was *** the presence of H2O,the molecular oxygen is more favorable to be dissociated to generate•OH on the oxygen vacancies of the Pt SA/MgO surface,which is the dominant active oxygen *** anticipate that this work may shed light on further investigation of t10.1007/s12274-020-2765-1he oxidation mechanism of toluene and other VOCs over noble metal catalysts.

关键词： single-atom Pt activation of molecular oxygen oxygen vacancies active oxygen species oxidation of toluene

A kind of photonic crystal fiber with high birefringence and low cofinement loss

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Optoelectronics Letters 2008年第2期4卷 110-113页

作者： GONG Tao-rong YAN Feng-ping WANG Lin LIU pen.LI yi-fang JIAN Shui-sheng Key-Laboratory of All- Optical networks and Advanced Communication Networks Ministry of Education Beijing Jiatong University Beijing 100044 China Institute of Lightwave Technology Beijing Jiaotong University Beijing 10004 China

The triangular-lattice highly birefringent photonic crystal fibers(PCFs) with gradually increasing diameter of the air holes along radial axis are put forward. The modal birefringence, dispersion and confinement loss of the fundamental mode are simulated by full vector Galerkin finite element method(FEM) with a perfectly matched layer(PML). The results show that this PCF can keep low confinement loss when the rings of air holes are few. When the wavelength is 1.55 μm , the birefringence, the confinement loss of quick-axis and slow-axis are 1.365×10-3, 0.017 dB/m and 0.051 dB/m, respectively. A new way is proposed to fabricate polarization-mainting fibers with high performance.

关键词：光子晶体纤维高双折射低损耗光学元件

Evolution of hydrocarbon generation of Jurassic source rock of the Lenke-1 well in Lenghu tectonic belt of Qaidam basin,China

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Mining Science and Technology 2009年第2期19卷 235-240页

作者： ZHU Yan-ming ZHANG Ming JIANG Bo pen.De-hua yi Cheng-min ZENG Chun-lin WU ying School of Resource and Geoscience China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Qinghai Oilfield Company PetroChina Dunhuang Gansu 736202 China

The Lenghu tectonic belt is located at or near the northern margin in the Qaidam Basin,which is an intracontinental composite basin evolved during the Mesozoic and Cenozoic *** Lower Jurassic is considered a good source rock with a wide *** the deposit of the Lower Jurassic hydrocarbon source rock,the basin has undergone many tectonic events of subsidence and *** source rocks in the Lengke-1 well,have experienced a complicated tectonic-burial history during which different hydrocarbon generation(HG) evolutions have taken *** have investigated the history of burying,heating and hydrocarbon generation of the Lower Jurassic source rocks,not just on the basis of tectonic disturbance and deep burial,but also from new studies in fluid inclusion measurements and the application of numerical simulation with EASY%*** study reveals the evolution process,tectonic episodes and the strength of the HG of the Jurassic source *** conclude that twice HG processes have taken place since the Lower Jurassic formation and infer from that the important conclusion that more HG of the Lower Jurassic source rock took place during the Eocene-Miocene ***,we discuss the oil and gas tarp formation and destruction in the Lenghu tectonic belt and point out that more attention should be paid to the thrust faults,which formed during the late Himalayan epoch.

关键词： Lower Jurassic source rocks hydrocarbon generation EASY%Ro numerical simulation Lenghu tectonic belt

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一类创新型权证的数学模型

同济大学学报（自然科学版） 2011年第6期39卷 935-940页

作者：刘易任学敏同济大学应用数学系上海200092

为了解决中国证券市场股权分置这一体制性矛盾,一些上市公司推出了派发创新型权证的股改方案,该创新型权证将股票与权证相捆绑,从而不能假定股票收益呈现几何布朗运动.为了对该创新型权证定价,利用研究信用风险的结构化方法,以公司资产... 详细信息

为了解决中国证券市场股权分置这一体制性矛盾,一些上市公司推出了派发创新型权证的股改方案,该创新型权证将股票与权证相捆绑,从而不能假定股票收益呈现几何布朗运动.为了对该创新型权证定价,利用研究信用风险的结构化方法,以公司资产作为基本变量,对有担保与无担保的情况分别计算出该创新型权证的定价公式,对不同市场变量对于创新型权证价格的影响作了理论和数值分析.

关键词：创新型权证结构化模型信用风险

Effect of Qingguang'anⅡon expressions of OX42 protein and IL-1βmRNA of retinal microglia cells of rats with chronic high intraocular pressure

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International Journal of Ophthalmology(English edition) 2018年第2期11卷 326-328页

作者： Ya-Sha Zhou Jian Xu Jun pen. Yue Liu Gen-Yan Qin yi-Jing Yang Qing-Hua pen.Han-Yu Tan Hunan University of Traditional Chinese Medicine Changsha 410208Hunan ProvinceChina The First Affiliated Hospital of Hunan University of Traditional Chinese Medicine Changsha 410007Hunan ProvinceChina

The study investigated the effects of Qingguang＇an Ⅱ（a Chinese medicinal preparation） on expressions of OX42 protein and interleukin-1β（IL-1β） mRNA of retinal microglia cells of rats with chronic high intraocular pressure（IOP）. SD rats were randomly divided into 6 groups, that were： A： blank group; B： model group; C： Qingguang＇an Ⅱ low dose group; D： Qingguang＇an Ⅱ medium dose group; E： Qingguang＇an Ⅱ high dose group; F： yimaikang disket（a Chinese medicinal preparation） group. Experimental rats in B, C, D, E, F groups were established the model of chronic high IOP by cauterizing of superficial scleral vein. Tissues of eyes were obtained after intragastric administration for 2 and 4 wk. At the time-point of 2 wk, OX42 protein and IL-1β mRNA in group B were statistically expressed in higher level comparing with other groups（P〈0.05）. Moreover, at the time-point of 4 wk, OX42 protein and IL-1β mRNA in groups C, D and E were statistically expressed in lower level comparing with group F（P〈0.05）. Besides, OX42 protein and IL-1β mRNA in groups C and D were statistically expressed in higher level comparing with group E（P〈0.05）. OX42 protein and IL-1β mRNA in groups C and D were expressed in similar level（P〉0.05）. The study indicated that, in the protection of optic nerve of rats with chronic high IOP, the high dose of Qingguang＇an Ⅱ at the time-point of 4 wk was the better choice.

关键词： Qingguang'an Ⅱ chronic high intraocular pressure OX42 protein interleukin-1β mRNA

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试论非物质文化遗产保护中的艺术档案工作

档案与建设 2006年第5期 12-14页

作者：彭毅江苏省文化艺术研究院江苏南京210002

根据2003年10月17日联合国教科文组织第三十二届大会上通过的《保护非物质文化遗产公约》定义：“非物质文化遗产指被各群体、团体、有时为个人视为其文化遗产的各种实践、表演、表现形式、知识和技能及其有关的工具、实物、工艺品和文... 详细信息

根据2003年10月17日联合国教科文组织第三十二届大会上通过的《保护非物质文化遗产公约》定义：“非物质文化遗产指被各群体、团体、有时为个人视为其文化遗产的各种实践、表演、表现形式、知识和技能及其有关的工具、实物、工艺品和文化场所。”非物质文化遗产包括五个方面：1．口头传说和表述，包括作为非物质文化遗产媒介的语言；2．表演艺术；3．社会风俗、礼仪、节庆；4．有关自然界和宇宙的知识和实践；5．传统的手工艺技能。

关键词：《保护非物质文化遗产公约》文化遗产保护表演艺术档案工作联合国教科文组织文化场所口头传说社会风俗工艺品自然界

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医学论文英语写作的文体特点

实用儿科临床杂志 2009年第17期24卷 1383-1384页

作者：任如意新乡医学院外语系河南新乡453003

随着现代医疗科技的飞速发展,医疗卫生领域国际间的学术交流与合作日益加强,掌握必要的医学论文英语写作知识,对提高医疗专业人士的专业能力十分重要。医学英语具有其独特的文体特征,现拟从英语文体学角度出发,探讨医学论文英语写作的... 详细信息

随着现代医疗科技的飞速发展,医疗卫生领域国际间的学术交流与合作日益加强,掌握必要的医学论文英语写作知识,对提高医疗专业人士的专业能力十分重要。医学英语具有其独特的文体特征,现拟从英语文体学角度出发,探讨医学论文英语写作的文体特点,具体体现在常用的词汇、句法等方面。掌握这些必要的医学英语论文写作技巧和知识对儿科临床工作者具有理论指导和实践意义。

关键词：医学英语文体特点词汇句法

海萤荧光素衍生物发光反应关键步骤的理论研究

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物理化学学报 2010年第10期26卷 2779-2786页

作者：孙颖任爱民闵春刚邹陆一任雪峰吉林大学理论化学研究所理论化学计算国家重点实验室长春130023

用不同取代基对化学发光物质6-芳基-2-甲基咪唑[1,2-α]吡嗪-3-(7H)酮环(海萤发光的类似物)的芳基位进行取代,形成系列海萤荧光素类似物MIPa-MIPd;并采用B3LYP/6-311+G(d,p)方法,通过电子抽取能(EEP)的计算和自然电荷布居分析(NPA),研... 详细信息

用不同取代基对化学发光物质6-芳基-2-甲基咪唑[1,2-α]吡嗪-3-(7H)酮环(海萤发光的类似物)的芳基位进行取代,形成系列海萤荧光素类似物MIPa-MIPd;并采用B3LYP/6-311+G(d,p)方法,通过电子抽取能(EEP)的计算和自然电荷布居分析(NPA),研究了在气相、二甲亚砜(DMSO)和二甘醇二甲醚(DG)中海萤发光的类似物从阴离子变化到自由基过程中取代基的作用.结果表明:在这个过程中,吲哚在DG中作为取代基(MIPb)时的EEP最小,电荷变化最大,说明这种取代基有利于反应的进行.

关键词：密度泛函理论海萤荧光素化学发光电子抽取能自然电荷布居分析

The First Critical Experiment of IHNI Reactor

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The First Critical Experiment of IHNI Reactor