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数量属差,同类反比
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作者 王秀娥 《中小学数学(小学版)》 2023年第5期31-32,共2页
我们知道,用杆秤称量物体的依据是杠杆原理:即当秤杆平衡时,物体重量和物体在秤杆上的受力点与秤毫之间的距离(我们称为物体力臂,以下同)的乘积等于秤碗重量和秤碗在秤杆上的受力点与秤毫之间的距离(我们称为秤力臂,以下同)的乘积。
关键词 属差 杠杆原理 受力点 力臂 物体 距离
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地方课程资源概念的厘清 被引量:7
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作者 王建虎 潘伟民 《毕节学院学报(综合版)》 2010年第1期117-120,共4页
随着全国地方课程的不断实施,各地都在积极开发与地方课程相适宜的资源以支持该地区地方课程的实施。然而由于对所使用的概念界定不清,严重影响着地方课程资源的合理开发和利用。通过对资源、地方课程、课程资源等概念进行系统剖析,充... 随着全国地方课程的不断实施,各地都在积极开发与地方课程相适宜的资源以支持该地区地方课程的实施。然而由于对所使用的概念界定不清,严重影响着地方课程资源的合理开发和利用。通过对资源、地方课程、课程资源等概念进行系统剖析,充分利用属差法,找出地方课程资源与其他资源的区别,并从本质属性和特点等角度对地方课程资源进行正确的定义。 展开更多
关键词 资源 课程资源 地方课程资源 属差
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科技法定义论析
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作者 倪正茂 《上海政法学院学报(法治论丛)》 1989年第3期33-35,共3页
科技活动中形成的科技社会关系,要求以法律手段加以调节,从而导致了科技法的产生。现在,科技法已成为部门繁多、自成体系并不断扩展的法律类型。但是,迄今为止,关于什么是科技法,却众说纷纭,尚无定论。目前学术界已经提出一些研究观点,... 科技活动中形成的科技社会关系,要求以法律手段加以调节,从而导致了科技法的产生。现在,科技法已成为部门繁多、自成体系并不断扩展的法律类型。但是,迄今为止,关于什么是科技法,却众说纷纭,尚无定论。目前学术界已经提出一些研究观点,兹择有代表性的摘录如下:①科技法是反映统治阶级的意志和利益,经国家制定和认可,以国家的强制力保证实施的行为规范。 展开更多
关键词 科技法 研究观点 法学理论 原子能法 行为规范 法律调整 科技研究成果 法律规范 法学词典 属差
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数学概念的定义方式 被引量:2
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作者 辛颖 《安徽电子信息职业技术学院学报》 2003年第1期12-13,共2页
数学概念是数学中推理判断,论证的基础,是培养学生能力和发展智力的起点,本文通过五个方面,阐述数学概念的定义方式,揭示了概念类型、特点、内容。培养学生逻辑思维能力,是数学教师必备的素质。
关键词 思维形式 属差 内涵 外延 最近种概念
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Description of a New Subspecies of the Genus Saurogobio Bleeker (1870) 被引量:3
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作者 戴应贵 杨君兴 《Zoological Research》 CAS CSCD 北大核心 2002年第4期306-310,共5页
The genus Saurogobio Bleeker (1870) is a group of small sized cyprinids. Saurogobio dabryi Bleeker (1871) is widely distributed in East Asia.On the basis of careful inspection of morphological and meristic ch... The genus Saurogobio Bleeker (1870) is a group of small sized cyprinids. Saurogobio dabryi Bleeker (1871) is widely distributed in East Asia.On the basis of careful inspection of morphological and meristic characters of specimen collected from Chenghai Lake in Yunnan and the opening river systems including Pearl River,Minjiang River,Yangtze River,Liaohe River and Songhuajiang River,the Chenghai Lake population of Saurogobio dabryi is considered to represent a new subspecies, Saurogobio dabryi chenghaiensis . Saurogobio dabryi chenghaiensis is distinguished by the combination of following characters.Rostral cap developed,covering over upper lip,and lips with developed papillae.Body and caudal peduncle very slender,body depth 12 7%-15 0% of standard length(SL),caudal peduncle depth 5 5%-6 1% of SL and 31 8%-39 1% of caudal peduncle length.A longitudinal dark stripe present along the axis on each side of body and 6-11 stick shaped black spots (its widths being 25%-50% of its lengths respectively) occur along the stripe.Distance from pelvic fin origin to anus is more than 50% of pelvic fin length.The length of the shortest caudal fin ray is less than 50% that of the longest one.The new subspecies occurs only in Chenghai Lake,Yunnan,China. 展开更多
关键词 Saurogobio New subspecies Coefficient of difference KEY
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江西发现差齿姬蜂属三新种(膜翅目,姬蜂科,柄卵姬蜂亚科)并附中国已知种检索表 被引量:2
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作者 盛茂领 孙淑萍 《动物分类学报》 CSCD 北大核心 2011年第4期961-969,共9页
报道在江西发现的差齿姬蜂属Thymaris Frster,1869的种类,其中有3新种:黄足差齿姬蜂Th. flavipedalis sp.nov.,红颈差齿姬蜂Th. ruficollaris sp.nov.,沟差齿姬蜂Th. sulcatus sp. nov.和中国1新纪录种纺差齿姬蜂Th. clotho Morley,... 报道在江西发现的差齿姬蜂属Thymaris Frster,1869的种类,其中有3新种:黄足差齿姬蜂Th. flavipedalis sp.nov.,红颈差齿姬蜂Th. ruficollaris sp.nov.,沟差齿姬蜂Th. sulcatus sp. nov.和中国1新纪录种纺差齿姬蜂Th. clotho Morley,1913。指出了新种与近似种的鉴别特征,并附彩色特征图。编制了该属中国已知种的检索表。 展开更多
关键词 膜翅目 姬蜂科 柄卵姬蜂亚科 齿姬蜂 新种 检索表
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概念在中国思维之形态中的“非定义化”特征
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作者 陈焱 《哲理(论坛版)》 2010年第3期187-188,共2页
在文化这个大标题之下的各种思维形态,譬如抽象思维,形象思维能力等等,我们都可以认为是一种普遍在全球各个民族中都能被发现的基本思维能力。但另一方面,在各民族的文化中,又有其明显的思维偏向和侧重。同时我们也发现,在中华民... 在文化这个大标题之下的各种思维形态,譬如抽象思维,形象思维能力等等,我们都可以认为是一种普遍在全球各个民族中都能被发现的基本思维能力。但另一方面,在各民族的文化中,又有其明显的思维偏向和侧重。同时我们也发现,在中华民族和中华文化的思维中,明显缺少一种古希腊式的对抽象概念(特别是哲学上的))进行精确定义的思维模式。本文希望以《中国思维形态》一书对于中国传统文化中思维形态各方面的普遍阐述为基础,对照于古希腊种加属差的定义思维模式;以进一步发现中国思维在定义抽象概念,特别是中国传统哲学抽象概念的问题上,所具有的特征和方法。 展开更多
关键词 中国思维形态 种加属差 描述 实践
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论新闻语言和缩略语——兼论新词语的理据
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作者 郭熙 《许昌学院学报》 CAS 1989年第1期41-44,共4页
新闻语言,简言之,即报纸、广播、电视等方面经常使用的语言。缩略语,是指语言中一些比较复杂的语言形式的简化用法。我们在这里把它们放在一起讨论,是因为新闻语言是缩略语运用的一个重要阵地,而缩略语又是新闻语言的特色之一。我们说... 新闻语言,简言之,即报纸、广播、电视等方面经常使用的语言。缩略语,是指语言中一些比较复杂的语言形式的简化用法。我们在这里把它们放在一起讨论,是因为新闻语言是缩略语运用的一个重要阵地,而缩略语又是新闻语言的特色之一。我们说新闻语言是缩略语的一个重要阵地,并不是说缩略语要依赖于新闻语言。新闻和语言都是社会现象,都随着社会的产生而产生①,随着社会的发展而发展。不过,新闻语言的形成。 展开更多
关键词 新闻语言 任意性 兼论 电视新闻 理据性 属差 中国新闻业史 索绪 引者 李葆嘉
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“四边形”一章教学的尝试
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作者 靳铁珍 《中学数学教学》 1985年第2期9-12,共4页
本篇是绩溪会议上交流的论文,刊载时作些删节。平面几何课的教学进行到第三章'四边形'时,师生都有'可以喘11气了'的感觉。因为有了第一、二章的基础,学生认为上课老师讲的都能听懂了,课后习题也会做了。教师觉得教材简... 本篇是绩溪会议上交流的论文,刊载时作些删节。平面几何课的教学进行到第三章'四边形'时,师生都有'可以喘11气了'的感觉。因为有了第一、二章的基础,学生认为上课老师讲的都能听懂了,课后习题也会做了。教师觉得教材简单,备课、讲课都轻松多了。总之, 展开更多
关键词 教学实例 课后习题 判断推理 三角形中位线 逻辑推理能力 课堂练习 几何教学 平面图形 填写表格 属差
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试论数学概词
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作者 薛茂芳 《潍坊工程职业学院学报》 1988年第S1期28-32,共5页
定义、名称和符号,是数学概念在三个不同层次上的识记信息,是数学概念教学中相互联系而作用不同的三个富有实践意义的问题.本文从语言学角度出发,就数学概念的名称,即数学概词的几个基本问题,略过一孔之见,不妥或谬误之处,望请批评指正.
关键词 异次根式 语言学角度 最简二次根式 属差 概念定义 形象思维能力 一元一次不等式 定义法 函数概念 无限不循环小数
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被游戏机“俘虏”的孩子们
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作者 吕志斌 《市场研究》 1994年第9期36-37,共2页
在城市大街两旁,人们都可以看到装饰各异的电子游戏室(厅),等待着孩子们“光临”。这种高科技的电子匣子在吞食孩子们为数不多的零花钱、早点钱甚至车票钱的同时,也在无形中影响着他们的学业和成绩。
关键词 属差 上课时间 打麻将 请看 给你 社会后果 应道 文化部门 社会影响 敷衍应付
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手表的传统与现代
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作者 林岳 《董事会》 2015年第6期102-103,共2页
没有不好的行业,只有不好的企业,"传统"有时在新时代浪潮面前容易变得岌岌可危,就如手机替代固定电话、数码相机替代胶卷相机一样势不可挡,但还是有一些东西是"智能化浪潮"所不可替代的包括Swatch集团在内的众多传统手表企业可能都... 没有不好的行业,只有不好的企业,"传统"有时在新时代浪潮面前容易变得岌岌可危,就如手机替代固定电话、数码相机替代胶卷相机一样势不可挡,但还是有一些东西是"智能化浪潮"所不可替代的包括Swatch集团在内的众多传统手表企业可能都没有想到一个问题,那就是不管你的手表有多好,不管什么场合,对消费者来讲,基本上只可能戴一只表,也就是说你只能"占领"一只手腕。从穿着搭配和品味,以及功能性来讲, 展开更多
关键词 移动支付 时代浪潮 视频通话 劳力士 机械设计 外观设计 百年灵 属差 历史故事 口碑传播
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Varietal differences in photosynthetic characters and chlorophyll fluorescence induction kinetics parameters among intergeneric progeny derived from Oryza×Sorghum, its parents, and hybrid rice 被引量:2
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作者 KatsuyoshiShimizu 唐建军 陈欣 《Journal of Zhejiang University Science》 CSCD 2002年第1期113-117,共5页
A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63... A comparative study on the photosynthetic parameters among intergeneric progenies derived from \%Oryza sativa\% L.×\%Sorghum vulgare\% L., its maternal parent Gui 630 and commercial 3\|line hybrid rice Shanyou 63 in pot experiment in greenhouse was conducted. The morphological and photosynthetic characters of canopy leaves and chlorophyll fluorescence kinetic parameters including \%F\%\-v/\%F\%\-m, \%F\%\-v/\%F\%\-0, photochemical quenching coefficient and non\|photochemical coefficient of canopy leaves of 3 varieties were measured. The results showed the progeny, Yuanyou 1, derived from an intergeneric cross of rice and sorghum possesses better canopy spatial architecture with thicker, heavier and bigger canopy leaf than its maternal parent Gui 630. Higher photosynthetic rate due to higher chlorophyll content, higher primary energy transformation efficiency, potential of PSII and non\|photochemical quenching coefficient (\%q\%\-E) were also measured in Yuanyou 1. These explain partly why the intergeneric progeny has higher biomass production, and better tolerance to adverse conditions and higher field yields even under stress conditions. 展开更多
关键词 intergeneric hybrid PHOTOSYNTHESIS chlorophyll fluorescence kinetics non\|photochemical quenching
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Fuzzy logic controller design with unevenly-distributed membership function for high performance chamber cooling system 被引量:2
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作者 曹健鹏 Seok-Kwon Jeong Young-Mi Jung 《Journal of Central South University》 SCIE EI CAS 2014年第7期2684-2692,共9页
Fuzzy logic controller adopting unevenly-distributed membership function was presented with the purpose of enhancing performance of the temperature control precision and robustness for the chamber cooling system.Histo... Fuzzy logic controller adopting unevenly-distributed membership function was presented with the purpose of enhancing performance of the temperature control precision and robustness for the chamber cooling system.Histogram equalization and noise detection were performed to modify the evenly-distributed membership functions of error and error change rate into unevenly-distributed membership functions.Then,the experimental results with evenly and unevenly distributed membership functions were compared under the same outside environment conditions.The experimental results show that the steady-state error is reduced around 40% and the noise disturbance is rejected successfully even though noise range is 60% of the control precision range.The control precision is improved by reducing the steady-state error and the robustness is enhanced by rejecting noise disturbance through the fuzzy logic controller with unevenly-distributed membership function.Moreover,the system energy efficiency and lifetime of electronic expansion valve(EEV) installed in chamber cooling system are improved by adopting the unevenly-distributed membership function. 展开更多
关键词 chamber cooling system fuzzy logic controller unevenly-distributed membership function steady-state error reduction ROBUSTNESS variable speed refrigeration system
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Axisymmetrical Nonlinear Bending and Buckling of a Circular Plate Under Large Load 被引量:2
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作者 侯朝胜 岳燕玲 《Transactions of Tianjin University》 EI CAS 2005年第3期216-222,共7页
With the terms of the exact series solution taken as trial functions, the method of point collocation was used to calculate the large deflection of a circular plate. The axisymmetrical bending formulae were developed ... With the terms of the exact series solution taken as trial functions, the method of point collocation was used to calculate the large deflection of a circular plate. The axisymmetrical bending formulae were developed for the calculation of a circular plate subjected to polynomial distributed loads, a concentrated load at the center, uniform radial forces and moments along the edge or their combinations. The support may be elastic. The buckling load was calculated. Under action of uniformly distributed load, central load or their compound load, solutions were compared with those obtained by other methods. Buckling beyond critical thrust was compared with that calculated by the power series method. The method presented in this paper has advantages of wide convergent range, high precision and short computing time. Moreover, the computing time is nearly independent of the complexity of the loads. 展开更多
关键词 circular plate large deflection BUCKLING compound load method of point collocation
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Argentinean Commercial Malbec Wines: Regional Sensory Profiles
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作者 Ana Carla Aruani Claudia Ines Quini +3 位作者 Hugo Ortiz Rodoifo Videla Marcelo Murgo Sebastian Prieto 《Journal of Life Sciences》 2014年第2期134-141,共8页
Sensory evaluation was performed on 32 commercial Malbec wines (2008 and 2009 vintages) produced in five provinces of Argentina. Wines from different areas in Mendoza (the most important producer of Malbec) were a... Sensory evaluation was performed on 32 commercial Malbec wines (2008 and 2009 vintages) produced in five provinces of Argentina. Wines from different areas in Mendoza (the most important producer of Malbec) were also included to test possible differences within this province. Ten key attributes were first recognized by descriptive analyses and then carefully evaluated by a trained sensory panel composed of 10 judges. Among the aroma and flavour attributes the analyses focused on plum, red fruits, white pepper, bell pepper, and floral. Three attributes of taste (acidity, astringency, and bitterness) and two attributes of color (red and blue-purple hues) were also analyzed. Statistical differences and similarities in sensory data were tested using analysis of variance (ANOVA), multiple means comparisons by least significant difference test (Fisher LSD), and principal component analysis (PCA). ANOVA and Fisher LSD tests of sensory data showed significant differences (P 〈 0.05) for 6 out of 10 wine attributes: plum, floral, red fruits, astringency, red and blue- purple hues. 展开更多
关键词 Malbec red wines commercial wines sensory analysis ARGENTINA Mendoza.
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New method for analyzing recrystallization kinetics of deformed metal by differential scanning calorimeter
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作者 陈建 马晓光 +3 位作者 李军 要玉宏 严文 范新会 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期849-854,共6页
The drawn copper wires have been analyzed by differential scanning calorimeter(DSC) and a new method, which uses DSC measurements to determine the Johnson-Mehl-Avrami-Kolmogorov(JMAK) exponent via introducing Arrheniu... The drawn copper wires have been analyzed by differential scanning calorimeter(DSC) and a new method, which uses DSC measurements to determine the Johnson-Mehl-Avrami-Kolmogorov(JMAK) exponent via introducing Arrhenius behavior and modifying the baseline of DSC curves, has been proposed. The results show that JMAK exponent and recrystallization activation energy of the drawn copper wires with a strain of 2.77 are about 2.39 and 125 k J/mol, respectively. The line linking the tangency points of DSC curve hypotenuse can be used as the baseline when calculating recrystallization fraction. The JMAK exponent obtained by the DSC method is in a good agreement with that obtained by microhardness measurements. Compared to traditional methods to measure the exponent, the proposed method is faster and less labor intensive. 展开更多
关键词 crystallization kinetics differential scanning calorimeter Johnson-Mehl-Avrami-Kolmogorov(JMAK) exponent deformed metal
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Formation mechanism and modulation of electromagnetically induced transparency-like transmission in side-coupled structures 被引量:2
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作者 杨辉 李宏建 +3 位作者 许秀科 何智慧 王云 徐国均 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2020-2026,共7页
Based on Fabry model and finite-different time-domain(FDTD) method, the plasmonic structure composed of a metal-insulator-metal(MIM) bus waveguide and a side-coupled resonator was investigated. It is found that the tr... Based on Fabry model and finite-different time-domain(FDTD) method, the plasmonic structure composed of a metal-insulator-metal(MIM) bus waveguide and a side-coupled resonator was investigated. It is found that the transmission features can be regulated by the cavity width and coupling distance. Electromagnetically induced transparency(EIT)-like transmission can be excited by adding an identical resonator on the pre-existing structure. Combining the foregoing theoretical analysis with coupled mode theory(CMT), the formation process of the EIT-like transmission was detailedly analyzed. EIT-like transmission can also be excited in plasmonic structure with two detuned resonators. By altering the structure parameters, the transparency window can be purposefully modulated. With the merits of compact structure and simplicity in fabrication, the proposed structures may have a broad prospect of applications in highly integrated optical circuits. 展开更多
关键词 metal-insulator-metal (MIM) waveguide side-coupled resonator electromagnetically induced transpareucy (EIT)-like transmission formation mechanism
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Greenhouse Gases Trapping
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作者 Terpugov Daniil Terpugov Grigory 《Journal of Chemistry and Chemical Engineering》 2013年第1期50-55,共6页
Climate change is the main problem of mankind, especially because of it's increasing speed and by specialists' forecast the situation will become worse. Climatic changes are correlated with the degradation of biosph... Climate change is the main problem of mankind, especially because of it's increasing speed and by specialists' forecast the situation will become worse. Climatic changes are correlated with the degradation of biosphere. It is a question of saving life on authors planet. The authors should begin taking strong measures, else Earth has a chance to repeat the destiny of Mars and Venus, as some scientists are afraid of. So reasoning like "When will it be and will it be at all" is for lazy, careless and selfish people. Now, because of the industrial emission of greenhouse gases, the temperature of the atmosphere is growing, the climate is changing: sudden temperature differences, snowfalls where it used to be impossible, thickness of arctic ice decrease is about 40% (a great ice-hole has been found on the north pole), repetition of droughts has increased in 8 times, power of hurricanes-2 times, increased power of floods. This is the result of lack of foresight, over-materialism and greediness, unwillingness to see the consequences because of the momentary advantages. How it is possible to trap CO2, SO2 and other gases? Commercially gas purification at thermoelectric power stations, ferrous and non-ferrous metallurgy plants, cement and chemical plants is being made with filters and cyclones that trap solid parts, and using different absorptive and adsorptive methods. Unfortunately at present there is no effective method of COE trapping. 展开更多
关键词 Climate change greenhouse gases carbon dioxide trapping direct osmosis.
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Theoretical Analysis on Optical Limiting Properties of Newly Synthesized Graphene Oxide-Porphyrin Composites
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作者 Yu-jin Zhang Wen-jing Yang +2 位作者 Jian-zhong Fan Yu-zhi Song Chuan-kui Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第3期257-262,I0001,共7页
Optical limiting (OL) properties and two-photon absorption (TPA) of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and f... Optical limiting (OL) properties and two-photon absorption (TPA) of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and field intensity equation with an iterative predictor-corrector finite-difference time-domain technique in nanosecond time domain. Our results show that graphene oxide-porphyrin composites exhibit enhanced OL behavior and possess larger TPA cross section compared with individual porphyrins. Interestingly~ unlike the previous result that porphyrin with heavier central metal shows better nonlinear abilities than that with- out metal substitute, graphene oxide-metal free porphyrin composite has stronger nonlinear absorption properties compared with graphene oxide-metal porphyrin composite. The com- putational results are in reasonable agreement with the experimental ones. Special attention has been paid to the influence of thickness of the medium and pulse width on TPA cross sections, which presents that larger TPA cross sections are obtained as the medium is thicker or the pulse duration is wider. 展开更多
关键词 Optical limiting Two-photon absorption Graphene oxide PORPHYRIN
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