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1.
《物理》1991,(11)
中国硅酸盐学会固态离子学专业委员会订于1992年11月3-6日在福州大学召开第六届全国固态离子学学术讨论会.福州大学校长黄金陵教授为本届会议筹备委员会主任. 征文内容:1. 无机阳离子导体.2.无机阴离子导体.3混合导体.4.质子导体.5.高分子快离子导体.6.固体中离子的运动与离子缺陷.固态离子学中的基础研究.7.固态离子学中的测试技术.8.高Tc超导体.9.快离子导体的应用研究:(1)固体电解质电池;(2)电化学传感器;(3)电显色器件.11.其他. 注意事项:1.应征论文必须是未在国内、外刊物上公开发表过;2.请将论文摘要(16开一页,约700字) 一式三份于19…  相似文献   

2.
近几年来,快离子导体的基础和应用研究都发展很快.这主要有两方面的原因:一方面因为快离子导体是一种具有液一固二象性的异常物态,通过对它的研究,有可能揭示出一些新的物理现象,所以凝聚态物理学家对它很感兴趣;另一方面,快离子导体可以作为各种电池的固体电解质,它是解决能源问题的一个重要途径.同时还可以用它做成一些离子器件或电化学器件,这引起其它领域的科学家对它的注意.随着研究工作的进展,可望形成凝聚态物理的一个重要分支──快离子导体物理学. 目前,研究快离子导体的方法很多,如电导率测量、核磁共振、X光衍射和中子散射、光…  相似文献   

3.
《物理》1979,(6)
全国快离子导体学术讨论会筹备会于1979年10月5日至7日在北京举行.参加会议的代表一致认为快离子导体的研究工作是一个蓬勃开展的薪领域.它的出现为固体物理开辟了一个新的分支——固体离子学.它的应用基础研究为传统电化学开辟了新的领域——固体电化学.快离子导体可以取代液体电解质做成高温燃料电池、高能量密度的动力电池和贮能电池,可望在节省能源、防止污染方面发挥重要作用。它还可能做成各种离子器件用在国防、工农业生产和人民生活方面.目前小型固体电池做电源的心脏起搏已经应用.定时器也在家庭电器和军事上开始应用.其他离子器件…  相似文献   

4.
郭向欣  李泓 《物理》2011,40(10):648-655
离子导电材料既可以是载流子主要为离子的纯离子导体,也可以是载流子同时包括离子和电子的混合离子导体.这两类材料是电化学能量转换与储存、化学传感以及选择性透过膜等器件的关键材料.在这些器件中,均存在电极与电解质、颗粒与颗粒、不同晶粒之间的二维或三维的异质结界面.因此,离子与电子在异质结中的输运性质对器件性能有重要的影响.但...  相似文献   

5.
徐晗  张璐 《物理学报》2021,(6):314-323
晶界或异质界面诱发的空间电荷层(space charge layer,SCL)效应,被认为是氧离子导体电解质内界面附近区域载流子传输特性显著区别于体相区域的关键原因之一.现有研究多采用Poisson-Boltzmann(PB)方程预测SCL效应的影响规律,但其基于载流子电化学平衡假设,无法用于载流子存在宏观运动的工况,极大限制了相关传输机理研究.本文耦合Poisson方程和载流子质量守恒方程,建立了适用于载流子具有宏观运动时氧离子导体内载流子传输过程的模型,推导了控制SCL效应的关键无量纲参数.聚焦固体氧化物燃料电池中常用的AO2-M2O3氧离子导体电解质,对比研究了传统PB方程和本文建立的Poisson-载流子质量守恒耦合方程的预测结果可靠性.进一步采用耦合模型深入分析了考虑SCL效应时氧离子导体内部氧空位传输机理,发现导体界面电流密度增大导致SCL电阻先减小后增大.增大无量纲Debye长度(表征空间电荷层厚度与导体厚度的比值)可显著增大SCL电阻.当驱动氧空位移动的过电势与热势数量级相当时,增大无量纲电势(表征过电势与热势的比值)导致SCL电阻增大;当过电势远小于热势时,改变无量纲电势对氧空位传输过程几乎无影响.本文研究结论可为通过合理设计晶界或异质界面以改善氧离子导体内载流子传输能力及最终提高相关电化学器件性能提供理论依据.  相似文献   

6.
最近十几年来,发现了一些离子电导率很高的固体材料即超离子导体或快离子导体.然而与液体电解质相比,其离子电导率仍然很低.为了克服这个缺点,在探索电导率更高的离子导体新材料的同时,也开展了离子导体薄膜的研究.本文综述了离子导体薄膜的研究情况. 一、薄膜生长和物理性质1.衬底 通常将薄膜制备在衬底上,以获得适当的机械强度.因而衬底材料的选择和处理就是离子导体薄膜研究中的重要问题. 在离子导体薄膜器件中通常有几个薄膜叠在一起,除了原始衬底外,每一层薄膜又成为下一层的衬底,这样就涉及到膜与衬底和膜与膜之间的相互作用.薄膜与衬…  相似文献   

7.
许政一  朱镛  张道范  李晨曦 《物理学报》1981,30(12):1576-1581
在我们以前的工作中,发现α-LilO3在c向直流偏压作用下表观介电常数增加。并把这一现象归结为由离子导电所产生。本文进一步研究了离子导体KLiSO4和NaCl单晶在直流偏压下的介电特性,也观察到了表观介电常数改变的现象,证实了上述结论的正确性。我们也研究了离子导体的这一特性与温度、频率和样品四周气氛的关系,讨论了它发生的条件。 关键词:  相似文献   

8.
丁屹  吴昆裕  俞文海 《物理学报》1987,36(8):1087-1092
结合快离子导体玻璃的结构特点和倪嘉陵(Ngai) 的低能激发、弛豫、耗散统一理论, 依据非Markov 方程探讨了快离子的输运特点, 导出了非晶态快离子导体电导的频率一温度依赖关系. 理论方法与现有快离子导体电导理论不同, 结果表明与实验数据符合较好, 理论能较好地描述低温下电导的色散现象. 色散的程度与表征物质内部结构差异的参数— 红外发散指数n有关. 关键词:  相似文献   

9.
丁屹  吴昆裕  俞文海 《物理学报》1987,36(7):1087-1092
结合快离子导体玻璃的结构特点和倪嘉陵(Ngai)的低能激发、弛豫、耗散统一理论,依据非Markov方程探讨了快离子的输运特点,导出了非晶态快离子导体电导的频率-温度依赖关系。理论方法与现有快离子导体电导理论不同,结果表明与实验数据符合较好,理论能较好地描述低温下电导的色散现象。色散的程度与表征物质内部结构差异的参数——红外发散指数n有关。 关键词:  相似文献   

10.
经中国硅酸盐学会第三届理事会研究和中国科协学会工作部审定批准,快离子导体专业委员会已经正式成立.该委员会由中国科学院上海硅酸盐研究所、中国科学院物理研究所、北京钢铁学院等单位的11人组成,挂靠在中国科学院上海硅酸盐研究所. 快离子导体专业委员会于1987年2月25日至26日在中国科学院上海硅酸盐研究所举行了弟一次会议.会议由快离子导体专业委员会主任委员林祖教授主持. 会议回顾了1980年第一届中国快离子导体学术讨论会以来,国内快离子导体的研究、教学、应用开发与国际交往等方面的情况.会议讨论决定:(1)中国第四届快离子导体学…  相似文献   

11.
Abstract

During recent years the study of the vibrational structure of catalysts by laser Raman spectroscopy (LRS) and of the interfacial properties of adsorbed species on solid surfaces by resonance Raman spectroscopy (RRS) and surface-enhanced Raman spectroscopy (SERS) have comprised one of the major research activities in the area of Raman spectroscopy [1–10] as applied to catalysts [11, 12].  相似文献   

12.
表面增强拉曼散射(SERS)技术克服了拉曼光谱灵敏度低的缺点,可以获得常规拉曼光谱不易得到的分子结构信息,成为分子甚至单一分子痕量检测的一个重要手段,在生命科学、分析化学等领域得到了广泛的应用。SERS基底是SERS检测中的核心部件,只有少量特殊处理的贵金属才具有较强SERS效应,同时这些传统SERS基底一般都是一次性使用,这给实际使用造成资源的浪费。在简要介绍SERS光谱发展的基础上,重点介绍了近期在可循环SERS基底的制备和应用作一述评,并对可循环SERS基底的研究和发展做了展望。  相似文献   

13.
Andrzej Kudelski 《Surface science》2009,603(10-12):1328-1334
Raman scattering has usually a very low efficiency. Therefore, during the first five decades after its discovery, Raman spectroscopic investigations of adsorbate-covered surfaces (except surfaces of highly porous samples) were out of reach. This changed in 1970s, when for molecules adsorbed on some surfaces, very large increase of the intensity of Raman spectrum (denoted as surface-enhanced Raman spectroscopy – SERS) was reported. In the past decade, two other very important achievements in surface Raman spectroscopy have been made: observation of SER spectrum of a single molecule and coupling of Raman spectroscope with the scanning probe microscope (STM or AFM) allowing a significant increase in the spatial resolution of Raman measurements in so-called tip-enhanced Raman spectroscopy (TERS). In the latter approach, fine tip made of a metal that supports surface plasmon resonances (such tip may be treated as a very local electromagnetic resonator) is brought at the nanometer distance above the surface, which induces large increase of the Raman scattering from molecules adsorbed at a surface located underneath the tip. This short review presents an overview of the state of the art and further possible applications of Raman spectroscopy in surface analysis. We mainly focus on SERS and TERS. Future prospects in these fields are also discussed.  相似文献   

14.
This paper highlights the use of Raman, FT-Raman and surface-enhanced Raman scattering (SERS) techniques for the study of humic substances. In contrast to other technologies which reveal information only about the average compositions and the kinds of functional groups present in humic substances, Raman and especially FT-Raman spectroscopies characterize the building blocks of humic substances and their changes in derivation and separation processes. Furthermore, surface-enhanced Raman scattering (SERS) techniques are able to readily detect humic substances and co-existing organic species at low concentrations typically found in natural environments and reveal definitive information about the specific groups in humic substances that bind on metal electrodes. Further applications of both Raman and SERS techniques can be extended to complicated systems as well as real environmental samples. Experiments have demonstrated: (1). the backbones of humic substances are structurally disordered carbon networks in most cases; (2). The backbones of humic substances from different sources and types are similar to each other; (3). Normal Raman spectroscopic study of humic substances should concentrate on the use of near-IR laser(s) resulting from strong fluorescence background and self-adsorption under the excitation with visible laser irradiation; (4). FT-Raman spectroscopy is the required analytical method to assess the effectivity of fractionation methods; (5). SERS spectra of humic substances on metal colloids and films are in most aces very similar to the corresponding Raman spectra of neutralized samples; (6). SERS techniques are very sensitive and highly selective, also both visible lasers and near-IR lasers can be used for SERS study; (7). SERS spectra on metal electrodes may provide additional information about the binding sites and adsorption mechanisms of humic substances on metal surfaces.  相似文献   

15.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous atmospheric pollutants and food contaminants, which exhibit potent carcinogenicity, mutagenicity, and teratogenicity. Vibrational spectroscopy techniques, especially Raman spectroscopy and surface‐enhanced Raman spectroscopy (SERS), can be potentially used as an alternative technique to liquid and gas chromatography in PAH analysis. However, there is limited information on the intrinsic Raman and SERS fingerprints of PAHs. In this study, we have acquired the Raman and SERS spectra of seven PAH compounds and compared their experimental spectra with theoretical Raman spectra calculated by density function theory (DFT). The vibrational modes corresponding to the Raman peaks have also been assigned using DFT. Characteristic Raman and SERS peaks have been identified for five PAH compounds, and the limits of detection were estimated. Such information could be useful for developing SERS assays for simple and rapid PAH identification. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

16.
Raman spectroscopy is a common tool for the qualitative and quantitative chemical analysis of molecules. Although the unique identification of molecules is possible via their vibrational lines, high concentrations (mmol/l) are needed for their nonresonant excitation owing to their low scattering cross section. The intensity of the Raman spectra is amplified by the use of the surface‐enhanced Raman scattering (SERS) technique. While the use of silver sols results only in a limited reproducibility of the Raman line intensities, lithographically designed, nanostructured gold surfaces used as SERS‐active substrates should, in principle, combine the high sensitivity with better reproducibility. For this purpose, we have produced gratings of gold dots on Si(001) surfaces by means of electron beam lithography. Qualitative and quantitative investigations of crystal violet (CV) performed using nanostructured surfaces give high reproducibility and enhancement of the Raman lines. The substrates are reusable after cleaning; all results presented could be obtained from a single SERS substrate. For the experiments very low laser powers were used. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

17.
内吞金纳米粒子的鼻咽癌细胞SERS光谱   总被引:1,自引:0,他引:1  
采用内吞方法将金纳米粒子引入细胞内,测试分析单个活性CNE-1鼻咽癌细胞的常规拉曼光谱和SERS光谱,并对其进行初步谱峰归属。CNE-1细胞的常规拉曼光谱有6个主要的拉曼峰:718,1001,1123,1336,1446和1660cm-1;沉积于细胞内的金纳米粒子强烈地增强了细胞内生化物质拉曼信号,在内吞金纳米粒子的CNE-1细胞的拉曼光谱中出现了20多个SERS拉曼信号,主要拉曼峰的强度明显高于常规拉曼信号。DNA骨架振动(1026,1097,1336和1585cm-1)证明金纳米粒子通过内吞作用而进入细胞核内。结果表明,基于胶体金SERS技术可能为活性鼻咽癌细胞内生化物质的探测提供一种高灵敏的方法。  相似文献   

18.
本文对在过渡金属铁、镍电极表面制备得到的γ-氨丙基三甲氧基硅烷(γ-APS)膜进行了研究。实验中对硅烷膜用X-射线光电子能谱(XPS)、现场表面增强拉曼散射光谱(SERS)和原子力显微镜(AFM)进行了表征。X-射线光电子能谱(XPS)的结果发现存在两个N1s峰,表明γ-APS膜中的氨基有两种存在方式:自由氨基和质子化氨基。实验中还发现现场表面增强拉曼散射光谱(SERS)是研究金属/γ-APS体系中界面层结构非常有效的手段,SERS结果表明硅醇羟基和氨基发生了竞争吸附,且γ-APS分子在外加电位等条件的影响下吸附状态会发生一定变化。原子力显微镜(AFM)的表征结果在微观上显示电极表面的γ-APS膜上形成了一种较规则的微孔结构,这种结构可能与基底的性质有关。  相似文献   

19.
Conjugate acid–base forms of the drug metoclopramide were investigated by Raman spectroscopy in aqueous solutions and by surface‐enhanced Raman scattering (SERS), when the molecules were adsorbed on colloidal silver surfaces. Raman spectra were recorded at pH values below 8, metoclopramide being poorly water soluble at higher pH values. The SERS spectra of metoclopramide were recorded in the 3–11 pH range, even in spite of its low solubility at basic pH values. The Raman and SERS spectra were assigned by means of density functional theory (DFT) calculations. By monitoring several SERS marker bands, the protonated, neutral or the coexistence of both molecular species adsorbed on the colloidal silver particles could be evidenced. The adsorbate orientation was deduced to be perpendicular to the metal surface for the protonated molecular species and tilted for the neutral metoclopramide molecular species. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

20.
基于表面增强拉曼光谱(SERS)技术在非标记蛋白质研究方面的最新进展。SERS是一个特殊的拉曼光谱现象,对于众多被吸附到粗糙金属表面上的拉曼活性分析物,可以提供增强拉曼信号(通常可以增强几个数量级)。SERS是一个灵敏的,选择性的,和通用的技术,并且可以实时、快速的对数据进行采集。因此,在基于仪器仪表技术和数据分析方法以及SERS在生物体系中的诸多优势,SERS经历了快速的发展阶段。重点介绍几个采用SERS技术对生物体系的代表性研究。某些SERS的生物应用发展比较成熟,并已经可以小范围临床应用,而有些还停留在发展的初始阶段(实验室研究阶段)。讨论了最近发展起来的几种基于SERS技术定量分析的方法, 选择不同SERS活性基底和技术(如生物分子在电极上,胶体纳米粒子,周期性图案结构和基于针尖拉曼技术)对蛋白质进行直接研究。此外,根据SERS指纹信息的变化可以用来研究蛋白质-蛋白质,蛋白质-配体间的相互作用。基于SERS技术对生物分子进行定性和/或定量分析方面显示出了相当大的优势。  相似文献   

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