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1.
Morphology and structure of amorphous carbon films deposited with a pulsed arc source (LASER-ARC) have been studied using microscopical methods (SEM, TEM and AFM), electron diffraction and spectroscopical investigation (EELS). The parameters of the arc source and the deposition conditions (substrate temperature) influence morphology and structure of deposited amorphous carbon films. Especially the incorporation and growth of particles, embedded in the film have been investigated. By particle analysis using an optical microscope a majority of particles that is smaller than 500 nm has been determined. The morphology has been also demonstrated similar by AFM and TEM images. Their number and size of particles is strongly influenced by the deposition temperature. The structure of amorphous film is characterized by the EELS-spectra, but the particle structure was not detectable.  相似文献   
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Abstract— At 37°C the active form of phytochrome in lettuce seed cannot function to promote subsequent germination. This effect of high temperature is distinct from thermal acceleration of dark reversion from the active form of phytochrome to the inactive form, and may be due to reversible denaturation of phytochrome.
Repeated brief irradiations with far-red light inhibit subsequent germination in the whole seed, whereas a similar irradiation regime results in a strong enhancement of the development of growth potential (ability to expand against an externally-imposed osmotic restraint) in the excised axial portion of the seed. A possible explanation for these two opposing results, in volving two different pigment systems with effective loci in different parts of the seed, is suggested.  相似文献   
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The structure of 4-methyl-6-phenyl-2-(thiobenzoylmethylene)-2H-thiapyran (1) was investigated by ESCA, X-ray analysis and quantum chemical calculations. The no-bond interaction between the sulphur atoms (Rs…s = 3.000(1) Å) is caused by π-type interaction rather than by Coulomb-type interaction.  相似文献   
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The S 2p, N 1s and C 1s electron binding energies of some substituted thiourea derivatives, isothiouronium salts, thiazolthiones, 1,3,5-thiadiazin-2-thiones and 1,3,5-thiadiazinium salts have been measured using the X-ray photoelectron spectroscopy (ESCA). From binding energy shifts information concerning the charge distribution on the atoms in the molecules was obtained. The positive charge of the isothiouronium salts was found to concentrate on carbon and nitrogen atoms. The charge of the 1,3,5-thiadiazinium cations was found to be delocalized demonstrating the pseudoaromatic character of the electronic system.  相似文献   
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This paper deals with pattern formation in Langmuir monolayers of two sets of lipid mixtures that include (1) a fluorinated lipid for phase separation, (2) a polymerizable lipid for stabilization of the patterned structure, and (3) a unit for the presentation of biological recognition units. Differences in the distribution of these functionalities allow a polymerization of dispersed or continuous phase and a placement of the recognition units in crystalline or solid analogue phase. Also, a ternary mixture including a lipid modified with the tandem repeat domain of MUC1 plus a TN-antigen was studied. Based on the biphasic pattern obtained (starlike crystals of up to 50 μm with a fine structure of some micrometers), we also verified the potential of the laterally patterned monolayer to stimulate the immune system (quartz crystal microbalance). The second set of lipids combines a highly fluorinated itaconic ester (polymerizable unit) with the natural phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine.  相似文献   
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Journal of Thermal Analysis and Calorimetry - The interest in the use of cellulose fibers of increasingly smaller sizes in cementitious materials has increased in recent years. This paper brings...  相似文献   
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Ohne ZusammenfassungDer Forschungsgemeinschaft der deutschen Wissenschaft danken wir für die Gewährung eines Forschungsstipendiums, der I. G. Farbenindustrie Werk Wolfen und ganz besonders der I. G. Farbenindustrie Werk Höchst danken wir für die Überlassung von wertvollem Ausgangsmaterial.  相似文献   
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