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1.
M. Röder J. Hahn U. Falke S. Schulze F. Richter M. Hietschold 《Mikrochimica acta》1997,125(1-4):283-286
A series of BN films was deposited by means of r.f. magnetron sputtering of a h-BN target onto Si(1OO) surfaces. Hereby, the substrate bias voltage was varied. Special interest is focussed to the influence of the deposition parameters on the orientation of the growing hexagonal BN film with respect to the substrate. For structural investigation, cross section samples were prepared. In addition to HRTEM and diffraction investigations, especially electron energy loss spectroscopy (EELS) was applied successfully for phase identification. For negative bias voltages of U
B
=–300 V and U
B
=–350V, we found a phase system consisting of a first-grown 25 nm thick layer of hexagonal structure with the c axis parallel to the substrate surface followed by the cubic phase.Dedicated to Professor Dr. rer. nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthday 相似文献
2.
Simple binary solids can be found to adopt unprecedented structures when confined into nanometre-sized cavities, such as the inner cylindrical bore of single-walled carbon nanotubes (SWNT). In the case of the discussed Lal(x)@SWNT encapsulation composite, the Lal2 "crystal" fragment adopts the structure of bulk Lal3, with one third of the iodine positions unoccupied. A complete characterisation of the encapsulation composite was achieved using an enhanced digital restoration approach of high-resolution transmission electron microscopy (HRTEM) images. The resulting complex exit surface wave provides information about the precise structural data of both filling material and host SWNT, establishing the SWNT's chirality and thus enabling a prediction of the composite's overall electron-transport properties. 相似文献
3.
Nickel disilicide/silicon (001) interfaces were investigated by aberration corrected scanning transmission electron microscopy (STEM). The atomic structure was derived directly from the high spatial resolution high angle annular dark field STEM images without recourse to image simulation. It comprises fivefold coordinated silicon and sevenfold coordinated nickel sites at the interface and shows a 2 x 1 reconstruction. The proposed structure has not been experimentally observed before but has been recently predicted theoretically by others to be energetically favored. 相似文献
4.
A. Parlow E. Madelung J. Tausz R. Falke 《Analytical and bioanalytical chemistry》1933,92(7-8):278-281
5.
Role of buried ultra thin interlayer silicide on the growth of Ni film on Si(100) substrate 总被引:1,自引:0,他引:1
D.K. Sarkar M. Falke H. Giesler S. Teichert G. Beddies H.-J. Hinneberg 《Applied Physics A: Materials Science & Processing》2000,70(6):681-684
The presence of a buried, ultra-thin amorphous interlayer in the interface of room temperature deposited Ni film with a crystalline
Si(100) substrate has been observed using cross sectional transmission electron microscopy (XTEM). The electron density of
the interlayer silicide is found to be 2.02 e/?3 by specular X-ray reflectivity (XRR) measurements. X-ray diffraction (XRD) is used to investigate the growth of deposited
Ni film on the buried ultra-thin silicide layer. The Ni film is found to be highly textured in an Ni(111) plane. The enthalpy
of formation of the Ni/Si system is calculated using Miedema’s model to explain the role of amorphous interlayer silicide
on the growth of textured Ni film. The local temperature of the interlayer silicide is calculated using enthalpy of formation
and the average heat capacity of Ni and Si. The local temperature is around 1042 K if the interlayer compound is Ni3Si and the local temperature is 1389 K if the interlayer compound is Ni2Si. The surface mobility of the further deposited Ni atoms is enhanced due to the local temperature rise of the amorphous
interlayer and produced highly textured Ni film.
Received: 2 March 2000 / Accepted: 28 March 2000 / Published online: 11 May 2000 相似文献
6.
Stefan Spange Prof. Dr. Patrick Kempe Andreas Seifert Dr. Alexander A. Auer Dr. Petra Ecorchard Dr. Heinrich Lang Prof. Dr. Meiken Falke Dr. Michael Hietschold Prof. Dr. Andreas Pohlers Dr. Walter Hoyer Prof. Dr. Gerhard Cox Dr. Emanuel Kockrick Stefan Kaskel Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(44):8254-8258
7.
U. Falke 《Fresenius' Journal of Analytical Chemistry》1994,349(1-3):241
Transmission EELS measurements have been carried out on a-C:H films deposited by ion plating from acetone or n-hexane plasma using various substrate potentials. The calculated dielectric functions show low optical absorption in the range of 4 eV to 8 eV. The amount of sp3 hybridizised C atoms has been estimated by integration over the * and * band ranges in the core loss spectra. 相似文献
8.
Bezemer GL Falke U van Dillen AJ de Jong KP 《Chemical communications (Cambridge, England)》2005,(6):731-733
STEM-EELS and XPS investigation shows manganese oxide to be closely associated with cobalt nanoparticles supported on carbon nanofibers thereby improving selectivity in Fischer-Tropsch catalysis. 相似文献
9.
The low temperature resistance anomaly has been investigated in highly disordered Fe films (50–200 ppm) after quench condensation and after annealing of the films at different temperatures, which reduces the degree of disorder. An analysis of the data shows that with respect to the films annealed at room temperature and to bulk samples the Kondo temperature of a disordered film is reduced by a factor of two. 相似文献
10.
In complex foods, bioactive secondary plant metabolites (SPM) can bind to food proteins. Especially when being covalently bound, such modifications can alter the structure and, thus, the functional and biological properties of the proteins. Additionally, the bioactivity of the SPM can be affected as well. Consequently, knowledge of the influence of chemical modifications on these properties is particularly important for food processing, food safety, and nutritional physiology. As a model, the molecular structure of conjugates between the bioactive metabolite benzyl isothiocyanate (BITC, a hydrolysis product of the glucosinolate glucotropaeolin) and the whey protein α-lactalbumin (α-LA) was investigated using circular dichroism spectroscopy, anilino-1-naphthalenesulfonic acid fluorescence, and dynamic light scattering. Free amino groups were determined before and after the BITC conjugation. Finally, mass spectrometric analysis of the BITC-α-LA protein hydrolysates was performed. As a result of the chemical modifications, a change in the secondary structure of α-LA and an increase in surface hydrophobicity and hydrodynamic radii were documented. BITC modification at the ε-amino group of certain lysine side chains inhibited tryptic hydrolysis. Furthermore, two BITC-modified amino acids were identified, located at two lysine side chains (K32 and K113) in the amino acid sequence of α-LA. 相似文献