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Application of Electron Energy Loss Spectroscopy and Energy Filtering Transmission Electron Microscopy for Microchemical Studies in 2.25Cr-1Mo Steel
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作者 P.Parameswaran Ilse Papst +2 位作者 F.Hofer W.Grogger V.S.Raghunathan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第3期361-366,共6页
Electron enregy loss spectroscopy (EELS) and energy filtering transmission electron microscopy (EFTEM) investigation on 2.25Cr-lMo steel was carried out to understand the nature of evolution of secondary carbides. The... Electron enregy loss spectroscopy (EELS) and energy filtering transmission electron microscopy (EFTEM) investigation on 2.25Cr-lMo steel was carried out to understand the nature of evolution of secondary carbides. The filtered images obtained from two different ageing treatments indicate that the steel evolves to a more stable carbide namely M23C6 in comparison to M2C. Microchemical information was generated from EELS spectra. Suitable choice for estimating the microchemical state was discussed. To evaluate the behaviour of ageing an elemental ratio of Fe to Cr is employed. 展开更多
关键词 Ferritic steels 2.25Cr-lMo steel EFTEM eelS Ageing
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Behavioral migration diversity of the Yangtze River Japanese Eel,Anguilla japonica,based on otolith Sr/Ca ratios 被引量:11
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作者 郭弘艺 郑怡 +4 位作者 唐文乔 沈皓 魏凯 谢正丽 Katsumi Tsukamoto 《Zoological Research》 CAS CSCD 北大核心 2011年第4期442-450,共9页
The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from t... The Yangtze River estuary is the main production area of Anguilla japonica in China,as well as the only existing fishery area for adult eels.Japanese eels are distributed in the main rivers and many tributaries from the Yangtze River estuary to the upper Jinsha River,which extend to nearly 3 000 km.However,their migration behaviors remain relatively unknown.We analyzed the biological characteristics of 153 specimens of silver eels collected from the Jingjiang section of Yangtze River(31o30'N,120o42'E) between September and November,2008,and tested the sagittal Sr/Ca ratios of 27 specimens.Among the 153 specimens examined,85 were female and 68 were male,which translated to a female-male ratio of 1:0.8.The ages of the female specimens ranged from 3 to 7 a(average 5.52) with an average total length(TL) of(669±80) mm,average body weight(BW) of(555±229)g,average condition factor of 1.77±0.22,and average gonad somatic index(GSI) of 1.32±0.31.The ages of the males ranged from 3 to 5 a(average:4.38) with an average TL of(518±51) mm,average BW of(234±76) g,average condition factor of 1.62±0.18,and average GSI of 0.21±0.11.All biological parameters of females were significantly larger than those of the male specimens(P0.05).According to the average Sr/Ca ratio(7.99±1.05) ×10-3 of the elver mark of sagitta,17 individuals(62.96%) were river eels and 10 individuals(37.04%) were estuarine eels.Of 16 females,13 individuals(81.25%) were river eels and 3 were estuarine eels,while of 11 males,36.36% were river eels and 63.64% were estuarine eels.The analysis on Sr/Ca ratios for every growth layer group(GLG) indicated there were no significant differences between second-age males and females.However,significant differences were observed between the third-age,fourth-age,and migration-age male and female specimens.This was likely related to the fact that second-age eels of both sexes stay in the same inhabitation waters;however,as they grow older,they move to different areas. 展开更多
关键词 SAGITTA Age composition Growth parameter Anguilla japonica Silver eel Yangtze River estuary
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铀表面离子镀铝层初始氧化EELS和AES原位研究 被引量:3
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作者 白彬 鲜晓斌 +1 位作者 吕学超 蒋春丽 《核科学与工程》 CSCD 北大核心 2003年第4期361-365,共5页
利用电子能量损失谱(EELS)和俄歇电子能谱(AES)原位研究了铀表面离子镀铝改性层在室温,氧气超高真空环境中的初始氧化行为。铝镀层初始氧化行为与金属铝不同,铝镀层表面初始吸附、氧化速度快于金属铝,钝化能力比金属铝强。铝镀层与金属... 利用电子能量损失谱(EELS)和俄歇电子能谱(AES)原位研究了铀表面离子镀铝改性层在室温,氧气超高真空环境中的初始氧化行为。铝镀层初始氧化行为与金属铝不同,铝镀层表面初始吸附、氧化速度快于金属铝,钝化能力比金属铝强。铝镀层与金属铝相似,初始氧化物均以岛状形式生长,但岛状生长时间缩短。 展开更多
关键词 电子能量损失谱 eelS 俄歇电子能谱 AES 铝镀层 钝化能力
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铌表面初始氧化行为的EELS和AES研究 被引量:2
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作者 陆雷 白彬 +3 位作者 邹觉生 杨江荣 肖红 蒋春丽 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2004年第8期839-842,共4页
利用电子能量损失谱(EELS)和俄歇电子能谱(AES)研究室温下铌的初始氧化过程,研究表明:清洁表面铌的EELS的实验值与理论值较为符合;随着氧化程度的加剧,其体等离子体(BP)、表面等离子体(SP)以及价带间跃迁所造成的电子能量损失峰发生了... 利用电子能量损失谱(EELS)和俄歇电子能谱(AES)研究室温下铌的初始氧化过程,研究表明:清洁表面铌的EELS的实验值与理论值较为符合;随着氧化程度的加剧,其体等离子体(BP)、表面等离子体(SP)以及价带间跃迁所造成的电子能量损失峰发生了明显的偏移和强弱的变化,也解释了Nb→NbO→NbO2的初始氧化过程;另外,铌在潮湿空气里氧化1周,在其表面只生成很薄一层的Nb2O5氧化层。 展开更多
关键词 电子能量损失谱(eelS) 俄歇能谱(AES) 初始氧化
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高压绝缘α-Al_2O_3涂层的XPS和EELS表面分析 被引量:1
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作者 郑家贵 蒋立新 +2 位作者 蔡亚平 罗四维 周心明 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第2期201-204,共4页
用不同配方的Mn,Cr,Ti混合物涂复α-Al2O3绝缘瓷表面,在适当的条件下热处理,利用XPS和EELS测试分析了表面层的电子能态.发现在退火后各涂层成分的含量变化明显,由于配方元素不同程度地扩散、渗透进95Al2O3陶瓷基底内,通过反应生成... 用不同配方的Mn,Cr,Ti混合物涂复α-Al2O3绝缘瓷表面,在适当的条件下热处理,利用XPS和EELS测试分析了表面层的电子能态.发现在退火后各涂层成分的含量变化明显,由于配方元素不同程度地扩散、渗透进95Al2O3陶瓷基底内,通过反应生成了新相;根据价带谱和EELS分析,其表面层的价带顶移向真空能级,使能隙减小;能隙中的缺陷态、杂质态及表面态增加,有利于内次级电子的非弹性跃迁和二次电子发射系数的减小. 展开更多
关键词 氧化铝绝缘瓷 涂复热处理方法 XPS eelS 表面层 电子能态 二次电子发射系数 高压绝缘涂层
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Effects of Metal Ions and Organic Solvents on Alkaline Phosphatase from Rice-field Eel 被引量:7
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作者 黄毅 唐云明 《Agricultural Science & Technology》 CAS 2008年第2期112-115,共4页
[Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera... [Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^+ and K ^+ didn't generate big influences on enzyme activity;Mg^2+ and Ca^2+ could promote ALP while Li^+,Cu^2+ and Zn^2+ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism. 展开更多
关键词 Metal ion Organic solvent Alkaline phosphatase Rice-field eel
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计及饱和磁化的铁磁材料EEL损耗模型研究 被引量:1
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作者 赵志刚 赵安琪 +2 位作者 王丽美 高鹏旭 卢子奇 《电工电能新技术》 CSCD 北大核心 2023年第12期1-9,共9页
通过搭建复杂工况下磁特性测试系统,实验获得铁磁材料在正弦及不同谐波工况下的磁滞特性和损耗特性数据;基于磁滞回线等效的思想,在椭圆回线面积等效法(EEL)的基础上,充分考虑饱和磁化的影响,引入既能有效反映磁滞回线形状变化,又能准... 通过搭建复杂工况下磁特性测试系统,实验获得铁磁材料在正弦及不同谐波工况下的磁滞特性和损耗特性数据;基于磁滞回线等效的思想,在椭圆回线面积等效法(EEL)的基础上,充分考虑饱和磁化的影响,引入既能有效反映磁滞回线形状变化,又能准确描述动态磁化损耗特性的形状因数,对饱和磁滞回线进行有效的形状表征,建立适用于饱和磁通密度下的正弦EEL损耗模型,提高了EEL损耗模型在正弦高磁通密度工况下的计算精度。在此基础上,综合考虑畸变磁通所引起的局部磁滞回环对磁损耗的影响,采用磁滞回线解耦的方式,分别对主磁滞回环与局部磁滞回环做近似等效处理,进而建立谐波激励下的损耗模型,对磁心损耗进行有效的分析计算,扩宽了EEL模型的应用范围。最后结合磁特性装置进行相关实验验证,证明了本文所提铁心损耗建模方法具有良好的适用性和有效性。 展开更多
关键词 eel椭圆等效模型 形状因数 谐波激励 铁心损耗 磁特性测量
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类玻璃碳材料的EELS分析 被引量:1
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作者 张志力 Rik Brydson +1 位作者 Aidan Westwood Briand Rand 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2007年第A02期757-759,共3页
探讨以酚醛树脂为前驱物的类玻璃碳,在不同温度炭化处理过程中的微孔变化情况,利用透射电子显微镜中的能量损失谱(EELS)技术,观察其显微结构与化学结构的变化。高分辨电镜观察发现,材料呈现微晶石墨碳层围绕微小孔洞结构排列的无定形结... 探讨以酚醛树脂为前驱物的类玻璃碳,在不同温度炭化处理过程中的微孔变化情况,利用透射电子显微镜中的能量损失谱(EELS)技术,观察其显微结构与化学结构的变化。高分辨电镜观察发现,材料呈现微晶石墨碳层围绕微小孔洞结构排列的无定形结构,孔洞的形成主要是由小分子气化过程中产生的。由EELS图谱中的CK-edge分别对应于1s电子跃迁到π~*和σ~*反键轨道的两个特征峰,可计算得到C原子化学键SP^2杂化程度随炭化温度条件的不同有可观察到的比较明显的变化。 展开更多
关键词 酚醛树脂 无类玻璃碳 eelS
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掺杂(Fe、Nb)SrTiO_3晶界组成的电子能量损失谱(EELS)分析
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作者 方平安 顾辉 宋元伟 《材料科学与工艺》 EI CAS CSCD 2002年第1期48-50,共3页
采用高空间分辨率扫描透射电镜(STEM)对掺杂(Fe3+、Nb5+)SrTiO3晶界进行了观察,并利用采集的电子能量损失谱(EELS)对晶界组成进行了分析.结果表明,掺杂Fe的SrTiO3陶瓷晶界存在1nm左右的非晶膜,同晶体内部相比晶界缺Sr;三叉晶界为钛基玻... 采用高空间分辨率扫描透射电镜(STEM)对掺杂(Fe3+、Nb5+)SrTiO3晶界进行了观察,并利用采集的电子能量损失谱(EELS)对晶界组成进行了分析.结果表明,掺杂Fe的SrTiO3陶瓷晶界存在1nm左右的非晶膜,同晶体内部相比晶界缺Sr;三叉晶界为钛基玻璃相,Ti、O及Fe含量明显高于晶界.掺Nb的SrTiO3陶瓷晶界同晶粒相比同样缺Sr,三叉晶界主要以SiO2非晶相为主.Fe3+、Nb5+对Ti4+的替位及在晶界的偏析引起SrTiO3晶格畸变是导致晶界组成变化的主要原因. 展开更多
关键词 eelS SRTIO3 晶界 掺杂 偏析 陶瓷 钛酸锶 电子能量损失谱
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Determination of Weaning Regimes for Anguilla mormorata Glass Eels
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作者 徐长安 施建臣 +2 位作者 唐旭 方卫东 郭康姣 《Agricultural Science & Technology》 CAS 2013年第3期527-529,548,共4页
[Objective] The aim was to find a suitable weaning regime, including weaning period and weaning feed, for Angui//a mormorata glass eels. [Method] A weaning processing experiment was conducted indoor in fiberglass tank... [Objective] The aim was to find a suitable weaning regime, including weaning period and weaning feed, for Angui//a mormorata glass eels. [Method] A weaning processing experiment was conducted indoor in fiberglass tanks, two kinds of artificial feeds (eel grower powder feed and eel grower piece feed) were selected as weaning diets against a control group fed on natural food (minced octopus flesh), two weaning periods, 5 and 15 d, were introduced in weaning experiment. [Result] The growth rate and survival rate of the groups with 15-day's weaning period were higher than that of the groups with 5-day's weaning period, revealing that a 20% increase every 3 d from 0% to 100% in the proportion of grower paste in the minced octopus flesh during weaning is suitable for A. mormorata glass eels. [Conclusion] A. mormorata glass eels can be weaned from natural food to the commer- cially available eel grower feeds over a certain weaning period, and of the artificial feeds with same ingredients and nutrient, A. mormorata glass eels accepted powder feed more readily over 28 d than piece feed. 展开更多
关键词 Anguilla rnormorata Glass eel Weaning regime Artificial feed Natural food
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The Effects of Rearing Temperature on American Glass Eels
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作者 Carrie J. Blakeslee Heather S. Galbraith Robert M. Deems 《Agricultural Sciences》 2018年第8期1070-1084,共15页
American eels are declining throughout their range requiring a better understanding of physiological requirements of all life stages and optimal conditions for laboratory rearing and aquaculture. American glass eels (... American eels are declining throughout their range requiring a better understanding of physiological requirements of all life stages and optimal conditions for laboratory rearing and aquaculture. American glass eels (Anguilla rostrata) were housed for 3 weeks at 14&degC, 18&degC, 22&degC, or 26&degC to determine optimal juvenile rearing temperature in the laboratory. All treatments exhibited weight gain over the course of the study except the 14&degC treatment;however, there were only marginal differences in final weight between the 18&degC and 14&degC treatments and no differences in length. Variation in length and weight generally increased as temperature increased with significant differences in the standard error of weight between 14&degC and the 22&degC and 26&degC treatments and between 18&degC and 26&degC. Mortality was significantly greater than expected by chance at 26&degC?(7 deaths) and no mortality was observed at 14&degC. Body condition (based on the residuals from the weight-length relationships), conversely, was lowest in the 14&degC treatment. Considering all response variables, optimal laboratory rearing conditions were observed between 18&degC - 22&degC. Within a week of experimentation, evidence of gas bubble disease was observed and by completion noted in all treatments except at 14&degC, likely as a function of decreased gas solubility at warmer temperatures. Levels of total gas pressure (103% - 108%) and &#916;p (28 - 54 mm Hg) values may account for the gas bubbles observed. 展开更多
关键词 eel Culture Gas BUBBLE Disease JUVENILE eelS
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南极eelpout(Lycodichthys dearborni)多聚体Ⅲ型抗冻蛋白基因的克隆及进化分析 被引量:4
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作者 於静 Chi Hing C.Cheng +1 位作者 Arthur L.DeVries 陈良标 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2005年第8期789-794,共6页
冰冻海洋中生存的南极eelpout(Lycodichthysdearborni)体内能合成高浓度的Ⅲ型抗冻蛋白(AFPⅢ)。为了寻找新的AFPⅢ基因,构建了L.dearborni肝脏cDNA文库。通过斑点杂交筛选此文库,发现一个2.87kb 的cDNA克隆,LD12。序列分析采用DNAssist... 冰冻海洋中生存的南极eelpout(Lycodichthysdearborni)体内能合成高浓度的Ⅲ型抗冻蛋白(AFPⅢ)。为了寻找新的AFPⅢ基因,构建了L.dearborni肝脏cDNA文库。通过斑点杂交筛选此文库,发现一个2.87kb 的cDNA克隆,LD12。序列分析采用DNAssist2.0和ClustalX1.8软件。结果显示,LD12分子由12个串联重复的片段构成,每一个片段编码一个61个氨基酸(aa)的Ⅲ型抗冻蛋白分子和一个9aa的连接子。这是第一次在合成AFPⅢ的极地鱼类中发现这样的多聚蛋白结构基因。有趣的是,组成、结构和起源都不相同的抗冻糖蛋白AF GP,其基因也呈现类似的多聚蛋白结构的现象。因此,这种独特的多聚基因结构可能是鱼类基因组在适应极端寒冷的环境中采取的一种普遍方式。 展开更多
关键词 南极eel pout Ⅲ型抗冻蛋白 串联重复 多聚体蛋白基因 基因家族进化
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跃变比判别热解Si-C-N陶瓷EELS定量分析的有效性 被引量:1
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作者 李凌燕 顾辉 +1 位作者 VESNA Srot PETER van Aken 《电子显微学报》 CAS CSCD 北大核心 2009年第2期168-174,共7页
电子能量损失谱(EELS)分析方法的运用为材料研究领域提供了有力的定性和定量手段。通过对内壳层电子激发谱跃变比的计算,能够获得样品相对厚度的参考信息。这一方法弥补了实验条件在同步采集等离子激发谱和内壳层电子激发谱方面的局限性... 电子能量损失谱(EELS)分析方法的运用为材料研究领域提供了有力的定性和定量手段。通过对内壳层电子激发谱跃变比的计算,能够获得样品相对厚度的参考信息。这一方法弥补了实验条件在同步采集等离子激发谱和内壳层电子激发谱方面的局限性,并为辨别EELS定量的可靠性提供依据。本文以Si3N4为例,对跃变比随样品相对厚度的变化规律进行了研究,并在低于最佳样品厚度的范围内得到了可靠的定量结果。类似的跃变比变化规律能够运用于成份均一的Si-C-N热解样品,然而对于非均一的Si-C-N退火样品则不适用。 展开更多
关键词 电子能量损失谱(eelS) 跃变比(jump ratio) 相对厚度(relative thickness)
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Atomic-Scale AES-EELS Analysis of Structure-Phase State and Growth Mechanism of Layered Nanostructures
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作者 Nikolay I. Plusnin 《Advances in Materials Physics and Chemistry》 2016年第7期195-210,共16页
A review of our experience in range of electron spectroscopy of the physical vapor-phase deposition and growth of single- and multilayer nanostructures with atomic scale interfaces is presented. The foundation of an i... A review of our experience in range of electron spectroscopy of the physical vapor-phase deposition and growth of single- and multilayer nanostructures with atomic scale interfaces is presented. The foundation of an innovative methodology for the combined AES-EELS analysis of layered nanostructures is developed. The methodology includes: 1) determination of the composition, thickness, and the mechanism of phase transitions in nanocoatings under the probing depth most appropriated for the range of film thickness 1 - 10 ML;2) quantitative iteration Auger-analysis of the composition, thickness and growth mechanism of nanocoating;3) structural and phase analysis of nanocoatings with use of the analysis of position, shape and energy of the plasmon EELS peak and with subtracting the contribution from the substrate;4) analysis of phase transitions with use of the shift of the plasmon Auger-satellite and 5) non-destructive profiling of the composition of nanocoatings over depth with use of a dependence of the intensity and energy of EELS peaks on the value of the primary electron energy. 展开更多
关键词 Surface Interface NANOCOATING Layered Nanostructures PVD Growth AES-eelS Combined Analysis Iteration AES Analysis eelS Depth Profiling Element and Phase Composition Atom-Scale Resolution
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基于STEM-EELS方法在纳米尺度上测量表面声子强度 被引量:4
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作者 刘秉尧 李宁 +3 位作者 孙元伟 李跃辉 高鹏 俞大鹏 《电子显微学报》 CAS CSCD 北大核心 2018年第5期474-480,共7页
单色仪和球差校正器的装备使得透射电子显微镜同时具备高空间和高能量分辨率。基于扫描透射电子显微镜-电子能量损失谱(STEM-EELS)方法可以实现在纳米尺度上测量材料的声子结构,这为研究表界面和缺陷的声子行为及其与微观结构之间的关... 单色仪和球差校正器的装备使得透射电子显微镜同时具备高空间和高能量分辨率。基于扫描透射电子显微镜-电子能量损失谱(STEM-EELS)方法可以实现在纳米尺度上测量材料的声子结构,这为研究表界面和缺陷的声子行为及其与微观结构之间的关系提供了强有力的手段。本文测量了六方氮化硼(h-BN)纳米片体内、表面、表面附近真空中声子信号的强度,利用多种拟合方法探究了其衰减行为并做出理论解释。对比了各种拟合方法的优缺点,讨论了它们的适用范围,提出了一套简单的经验公式来拟合真空中信号强度的衰减行为,并与其他拟合方法对比。 展开更多
关键词 单色仪 STEM-eelS 六方氮化硼 声子 定量分析
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铀表面钛镀层原位氧化行为的AES和EELS研究 被引量:2
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作者 白彬 鲜晓斌 +1 位作者 杨江荣 陆雷 《核动力工程》 EI CAS CSCD 北大核心 2003年第5期458-461,共4页
利用铀的电子能量损失谱(EELS)、俄歇电子能谱(AES)原位,研究了在室温下O2气氛中表面Ti膜初始氧化过程中表面结构的变化。结果表明,Ti膜的氧化速度比金属Ti更快;Ti膜氧化时与金属Ti一样可形成Ti(固溶O)、TiO、Ti2O3、TiO2,氧化物以岛状... 利用铀的电子能量损失谱(EELS)、俄歇电子能谱(AES)原位,研究了在室温下O2气氛中表面Ti膜初始氧化过程中表面结构的变化。结果表明,Ti膜的氧化速度比金属Ti更快;Ti膜氧化时与金属Ti一样可形成Ti(固溶O)、TiO、Ti2O3、TiO2,氧化物以岛状形式生长,并以多种氧化态并存;其氧化过程为Ti→Ti(固溶O)→TiO→Ti2O3→TiO2。 展开更多
关键词 铀表面 钛镀层 氧化 电子能量损失谱 俄歇电子能谱
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高强度CrMo钢的EELS和EDS面扫描研究
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作者 马钺 章晓中 袁俊 《电子显微学报》 CAS CSCD 北大核心 2002年第5期729-730,共2页
关键词 高强度CrMo钢 eelS EDS 面扫描 电子能量损失谱 合金钢 晶界分析 场发射电子显微镜
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Random amplified polymorphic DNA analysis of eel genome 被引量:3
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作者 QIU JIA JING YI PING LI(Shanghai Institute of Cell Biology Chincsc Acadcmy of Sci-ences) 320 Yue Yang Road, Shanghal 200031, China) 《Cell Research》 SCIE CAS CSCD 1999年第3期217-223,共7页
Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make... Eel family is a huge one, in which many kinds of eelsespecially some migratory eels, bear strong resemblance toeach other, and are therefOre difficult to be identified. Inthis study 29 random primers were used to make RAPDana1ysis for Japanese ee1 (Angui11ajaponica). European eel(Anguilla anguilla) and Pike eel (AIllrae1lesox cinereus).And totally 299 fragments were counted. Shared or spe-cific fragments were counted alld ge11etic similarity or ge-netic distance were calculated. The genetic similarity be-tween Japanese eel alld Pike eel is 0.68 and the geneticdistance between them is 0.32; those between Europeaneel and Pike eel are 0.72 and 0.28 respectively, and be-tween Japanese eel and Ellropean eel are 0.74 and 0.25 re-spectively. The method has been shown to be suitable tomolecular identification of eels. It provides an a1ternativeapproach to determine the relatiollship between species. 展开更多
关键词 eel RAPD pojymrphic fragments genetic distance
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VCSELs与EELs多模弛豫振荡的研究 被引量:1
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作者 李孝峰 潘炜 +2 位作者 罗斌 赵峥 邓果 《激光技术》 CAS CSCD 北大核心 2004年第3期248-250,258,共4页
根据多模速率方程 ,利用MATLAB提供的SIMULINK软件包对垂直腔面发射激光器 (VCSELs)和边发射激光器 (EELs)多模弛豫振荡进行了研究。结果表明 ,与单模情况相比 ,多模时EELs弛豫振荡频率增大、弛豫和延迟时间缩短 ,而VCSELs动态特性变化... 根据多模速率方程 ,利用MATLAB提供的SIMULINK软件包对垂直腔面发射激光器 (VCSELs)和边发射激光器 (EELs)多模弛豫振荡进行了研究。结果表明 ,与单模情况相比 ,多模时EELs弛豫振荡频率增大、弛豫和延迟时间缩短 ,而VCSELs动态特性变化不大。与此同时 ,在得出VCSELs的单模工作、高速调制以及提高偏置电流或自发辐射因子可改善两类器件动态特性等结论外还看到 ,VCSELs边模抑制比 (SMSR)随偏置电流变化率高于EELs;自发辐射因子增大时 ,边模强度同比例增大、主模强度减小 ,利用微腔效应有效控制自发辐射因子可以优化VCSELs的单模特性。 展开更多
关键词 垂直腔面发射激光器 边发射激光器 弛豫振荡 边模抑制比 自发辐射因子
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Changes in serum thyroid hormone levels and thyroid gland activity of artificially maturing female Japanese eel (Anguilla japonica) 被引量:2
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作者 曲宪成 Massaki Nagae +1 位作者 Sinji Adachi Kohei Yamauchi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第1期111-122,共12页
In order to evaluate the involvement of the thyroid gland in reproduction, thyroid functioning was described in female cultivated Japanese eel (Anguilla japonica) in progressive stages of sexual maturation induced by ... In order to evaluate the involvement of the thyroid gland in reproduction, thyroid functioning was described in female cultivated Japanese eel (Anguilla japonica) in progressive stages of sexual maturation induced by chum salmon pituitary homogenate (SPH) treatment. Serum thyroid hormones, thyroxine (T4) and triiodothyronine (T3) were also measured in each stage. Thyroid gland activity (epithelial cell height) was high before SPH injection (previtellogenic stage), further increasing at the early vitellogenic stage, thereafter decreasing to late vitellogenic and migratory nucleus stages. The profiles of both T3 and T4 changed during vitellogenesis, being high during previtellogenic and early vitellogenic stages, and subsequently declining, thus mimicking thyroid gland activity. These results suggest that the thyroid has relation with eel ovarian development during artificial maturation. 展开更多
关键词 Thyroid activity thyroxine (T4) triiodothyronine (T3) Japanese eel artificial maturation
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