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61.
AG Milekhin N Yeryukov AI Toropov D Dmitriev E Sheremet DR Zahn 《Nanoscale research letters》2012,7(1):476
ABSTRACT: We present a comparative analysis of Raman scattering by acoustic and optical phonons in InAs/AlAs quantum dot superlattices grown on (001) and (311)B GaAs surfaces. Doublets of folded longitudinal acoustic phonons up to the fifth order were observed in the Raman spectra of (001)- and (311)B-oriented quantum dot superlattices measured in the polarized scattering geometries. The energy positions of the folded acoustic phonons are well described by the elastic continuum model. Besides the acoustic phonons, the spectra display features related to confined transverse and longitudinal optical as well as interface phonons in quantum dots and spacer layers. Their frequency positions are discussed in terms of phonon confinement, elastic stress, and atomic intermixing. 相似文献
62.
Chloride and Indium‐Chloride‐Complex Inorganic Ligands for Efficient Stabilization of Nanocrystals in Solution and Doping of Nanocrystal Solids
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Vladimir Sayevich Chris Guhrenz Maria Sin Volodymyr M. Dzhagan Alexander Weiz Daniel Kasemann Eike Brunner Michael Ruck Dietrich R. T. Zahn Karl Leo Nikolai Gaponik Alexander Eychmüller 《Advanced functional materials》2016,26(13):2163-2175
Here, the surface functionalization of CdSe and CdSe/CdS core/shell nanocrystals (NCs) with compact chloride and indium‐chloride‐complex ligands is reported. The ligands provide not only short interparticle distances but additionally control doping and passivation of surface trap states, leading to enhanced electronic coupling in NC‐based arrays. The solids based on these NCs show an excellent electronic transport behavior after heat treatment at the relatively low temperature of 190 °C. Indeed, the indium‐chlorido‐capped 4.5 nm CdSe NC based thin‐film field‐effect transistor reaches a saturation mobility of μ = 4.1 cm2 (V s)?1 accompanied by a low hysteresis, while retaining the typical features of strongly quantum confined semiconductor NCs. The capping with chloride ions preserves the high photoluminescence quantum yield ( ≈ 66%) of CdSe/CdS core/shell NCs even when the CdS shell is relatively thin (six monolayers). The simplicity of the chemical incorporation of chlorine and indium species via solution ligand exchange, the efficient electronic passivation of the NC surface, as well as their high stability as dispersions make these materials especially attractive for wide‐area solution‐processable fabrication of NC‐based devices. 相似文献
63.
64.
Dallas G. Hoover Ph.D. Prasad S. Dhurjati Robert J. Leipold Dallas G. Hoover Ph.D. Dietrich Knorr Robert J. Fisher 《Food Biotechnology》2013,27(2):283-299
Modern Food Microbiology, Third Edition. J.M. Jay. Van Nostrand Reinhold, 115 Fifth Ave., New York, NY 10003. 642 pp. 1986. $29.95 (US). Title: Fermentation and Biochemical Engineering Handbook; Principles, Process Design, and Equipment Author(s): Henry C. Vogel (Editor) Publisher: Noyes Publications, Park Ridge, NJ. 1986 Principles of Fermentation Technology P.F. Stanbury and A. Whitaker Pergamon Press Inc., Elm3ford, NY, USA 225 pp., 1984, $19.25 (soft cover), $48.00 (hard cover) Biotechnology in Agricultural Chemistry H.M. Le Baron, R.O. Mumma, R.C. Honeycutt and J.H. Duesing (eds) ACS Symposium Series 33t, American Chemical Society, Washington, DC 367 pp., 1987, $64.95 (US) Supercritical Fluids ‐ Chemical and Engineering Principles and Applications T.G. Squires and M.E. Paulaitis (Editors) ACS Symposium Series #329, 294pp., $59.95 (US & Canada), $71.95 (Export) Title: Biogeneration of aromas. Authors: Parliment, T. H. and R. Croteau (Editors) Publishers: ACS Symposium Series, Washington, DC, 1986 Title: Ecology and Metabolism of Plant Lipids Author(s): Glenn Fuller and W. David Nes (Editors) Publisher: American Chemical Society. Symposium Series, Washington DC, 1986 Title: Chemistry and Function of Pectins Author(s): Fishman, M.L. and Jen, J.J. Publisher: ACS Symposium Series, Washington, DC 1986 “Plant Proteins: Applications, Biological Effects and Chemistry”; R.L. Ory (ed), ACS Symposium Series, American Chemical Society 1155 Sixteenth Street NW, Washington, DC 20036, USA 285 PP, 1986, $59.95 (U.S. and Canada) 相似文献
65.
Mathias Dietrich Guillaume Delaittre James P. Blinco Andrew J. Inglis Michael Bruns Christopher Barner‐Kowollik 《Advanced functional materials》2012,22(2):304-312
The nitrile imine‐mediated tetrazole‐ene cycloaddition reaction (NITEC) is introduced as a powerful and versatile conjugation tool to covalently ligate macromolecules onto variable (bio)surfaces. The NITEC approach is initiated by UV irradiation and proceeds rapidly at ambient temperature yielding a highly fluorescent linkage. Initially, the formation of block copolymers by the NITEC methodology is studied to evidence its efficacy as a macromolecular conjugation tool. The grafting of polymers onto inorganic (silicon) and bioorganic (cellulose) surfaces is subsequently carried out employing the optimized reaction conditions obtained from the macromolecular ligation experiments and evidenced by surface characterization techniques, including X‐ray photoelectron spectroscopy and FT‐IR microscopy. In addition, the patterned immobilization of variable polymer chains onto profluorescent cellulose is achieved through a simple masking process during the irradiation. 相似文献
66.
67.
Dietrich Braess 《Calcolo》2009,46(2):149-155
A posteriori error estimates for the nonconforming P
1 element are easily determined by the hypercircle method via Marini’s observation on the relation to the mixed method of Raviart–Thomas.
Another tool is Ainsworth’s application of the hypercircle method to mixed methods. The relation on the finite element solutions
is also extended to an a priori relation of the errors, and the errors of four different finite element methods can be compared.
相似文献
68.
Prabhas Kumar Yadav Falk Händel Christian Müller Rudolf Liedl Peter Dietrich 《Grundwasser》2013,18(1):47-53
Groundwater pollution with organic contaminants remains a world-wide problem. Before selection of any remediation technique, it is important to pre-assess contaminated sites with respect to their hazard. For this, several analytical and numerical approaches have been used and an initial assessment of contaminated sites the MS-Excel© tool “NAFLA” was developed. “NAFLA” allows a quick and straightforward calculation and comparison of some analytical approaches for the estimation of maximum plume length under steady-state conditions. These approaches differ from each other in source geometry, model domain orientation, and in the consideration of (bio)chemical reaction within the domain. In this communication, we provide details about the development of “NAFLA”, its possible usage and information for users. The tool is especially designed for application in student education, by authorities and consultants. 相似文献
69.
We prove that the first-order theory of the one-step rewriting
relation associated with a trace rewriting system is decidable but in
general not elementary. This extends known results on semi-Thue
systems but our proofs use new methods; these new methods yield the
decidability of local properties expressed in first-order logic
augmented by modulo-counting quantifiers. Using the main
decidability result, we define several subclasses of trace rewriting
systems for which the confluence problem is decidable. 相似文献
70.