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S. Roth

Bio: S. Roth is an academic researcher from Max Planck Society. The author has contributed to research in topics: Carbon nanotube & Polyacetylene. The author has an hindex of 44, co-authored 281 publications receiving 25195 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, the degree of stretching of polyacetylene was determined from the angle dependence of the ESR linewidth of stretched polyacetylacetylene, and the orientation was preserved during isomerization.

1 citations

Proceedings ArticleDOI
12 Oct 2005
TL;DR: In this article, the authors examined the reaction of single-wall carbon nanotubes (SWNTs), obtained by HiPco method, and double-wall (DWNTs) grown during a chemical vapor deposition process, towards fluorinating agent BrF3 using optical absorption spectra measurements.
Abstract: Reactivity of single‐wall carbon nanotubes (SWNTs), obtained by HiPco method, and double‐wall carbon nanotubes (DWNTs), grown during a chemical vapor deposition process, towards fluorinating agent BrF3 has been examined using optical absorption spectra measurements. The spectra of the fluorinated samples exhibited sets of distinctly resolved peaks with energies having close values for DWNTs and HiPco nanotubes. It was found that the peaks can be associated with energy transitions in (n,n‐l)‐type carbon nanotubes, which structure remained unchanged with fluorination.

1 citations

Proceedings ArticleDOI
TL;DR: In this paper, the hydrogen adsorption properties of the carbon nanotube materials were investigated by temperature dependent analysis of the 1H-NMR spectra, and they were produced with different kinds of catalysts and hydrogen loaded under 23 bar hydrogen pressure.
Abstract: We report proton nuclear magnetic resonance (1H‐NMR) measurements on hydrogen loaded single walled carbon nanotubes. The carbon nanotubes were produced with different kinds of catalysts and hydrogen loaded under 23 bar hydrogen pressure. The hydrogen adsorption properties of the carbon nanotube materials were investigated by temperature dependent analysis of the 1H‐NMR spectra.

1 citations

Journal ArticleDOI
TL;DR: In this article, anelastic spectroscopy experiments in HiPco carbon nanotubes from room temperature to 3 K showed a thermally activated relaxation process at about 25ÕK for frequencies in the kHz range.

1 citations

Journal ArticleDOI
TL;DR: In this paper, optical transmission measurements performed with a He-Ne laser on epitaxial and spray deposited thin (2-10 μm ) CdS layers at room temperature are reported.

1 citations


Cited by
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Journal ArticleDOI
TL;DR: Owing to its unusual electronic spectrum, graphene has led to the emergence of a new paradigm of 'relativistic' condensed-matter physics, where quantum relativistic phenomena can now be mimicked and tested in table-top experiments.
Abstract: Graphene is a rapidly rising star on the horizon of materials science and condensed-matter physics. This strictly two-dimensional material exhibits exceptionally high crystal and electronic quality, and, despite its short history, has already revealed a cornucopia of new physics and potential applications, which are briefly discussed here. Whereas one can be certain of the realness of applications only when commercial products appear, graphene no longer requires any further proof of its importance in terms of fundamental physics. Owing to its unusual electronic spectrum, graphene has led to the emergence of a new paradigm of 'relativistic' condensed-matter physics, where quantum relativistic phenomena, some of which are unobservable in high-energy physics, can now be mimicked and tested in table-top experiments. More generally, graphene represents a conceptually new class of materials that are only one atom thick, and, on this basis, offers new inroads into low-dimensional physics that has never ceased to surprise and continues to provide a fertile ground for applications.

35,293 citations

Journal ArticleDOI
TL;DR: In this paper, the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations, are discussed.
Abstract: This article reviews the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations. The Dirac electrons can be controlled by application of external electric and magnetic fields, or by altering sample geometry and/or topology. The Dirac electrons behave in unusual ways in tunneling, confinement, and the integer quantum Hall effect. The electronic properties of graphene stacks are discussed and vary with stacking order and number of layers. Edge (surface) states in graphene depend on the edge termination (zigzag or armchair) and affect the physical properties of nanoribbons. Different types of disorder modify the Dirac equation leading to unusual spectroscopic and transport properties. The effects of electron-electron and electron-phonon interactions in single layer and multilayer graphene are also presented.

20,824 citations

28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
Changgu Lee1, Xiaoding Wei1, Jeffrey W. Kysar1, James Hone1, James Hone2 
18 Jul 2008-Science
TL;DR: Graphene is established as the strongest material ever measured, and atomically perfect nanoscale materials can be mechanically tested to deformations well beyond the linear regime.
Abstract: We measured the elastic properties and intrinsic breaking strength of free-standing monolayer graphene membranes by nanoindentation in an atomic force microscope. The force-displacement behavior is interpreted within a framework of nonlinear elastic stress-strain response, and yields second- and third-order elastic stiffnesses of 340 newtons per meter (N m(-1)) and -690 Nm(-1), respectively. The breaking strength is 42 N m(-1) and represents the intrinsic strength of a defect-free sheet. These quantities correspond to a Young's modulus of E = 1.0 terapascals, third-order elastic stiffness of D = -2.0 terapascals, and intrinsic strength of sigma(int) = 130 gigapascals for bulk graphite. These experiments establish graphene as the strongest material ever measured, and show that atomically perfect nanoscale materials can be mechanically tested to deformations well beyond the linear regime.

18,008 citations

Journal ArticleDOI
19 Jun 2009-Science
TL;DR: This review analyzes recent trends in graphene research and applications, and attempts to identify future directions in which the field is likely to develop.
Abstract: Graphene is a wonder material with many superlatives to its name. It is the thinnest known material in the universe and the strongest ever measured. Its charge carriers exhibit giant intrinsic mobility, have zero effective mass, and can travel for micrometers without scattering at room temperature. Graphene can sustain current densities six orders of magnitude higher than that of copper, shows record thermal conductivity and stiffness, is impermeable to gases, and reconciles such conflicting qualities as brittleness and ductility. Electron transport in graphene is described by a Dirac-like equation, which allows the investigation of relativistic quantum phenomena in a benchtop experiment. This review analyzes recent trends in graphene research and applications, and attempts to identify future directions in which the field is likely to develop.

12,117 citations