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121.
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Monika Schuster Claudia Turecek Helga Lichtenegger Robert Liska 《Applied Surface Science》2007,254(4):1131-1134
Continuously increasing life expectancy results in a rising number of bone diseases and fractures. Replacements from natural sources are not only limited in their availability, they also have some serious disadvantages such as possible immunological reactions or transmission of diseases. New synthetic biodegradable materials based on photopolymers could be an alternative solution. In these investigations an acrylate-based monomer formulation has been developed, consisting of a biodegradable basis monomer which is derived from gelatin, different reactive diluents, an appropriate photoinitiator and filler materials. For the three-dimensional shaping process stereolithography is the method of choice because of its capability to produce cellular structures with high resolutions. 相似文献
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125.
K. Pradeesh Monika Agarwal K. Koteswara Rao G. Vijaya Prakash 《Solid State Sciences》2010,12(1):95-98
Quasi-one-dimensional lead (II) iodide compound, C14H18N2Pb2I6, with unique crystal structure was synthesized and solved for the crystal structure. These novel inorganic-organic hybrids have high thermal stability of upto 300 °C and show excitonic and charge-transfer features in their optical properties. An attempt has been made to understand the structural and optical mechanisms between inorganic one-dimensional polymeric PbI nano ribbons and the guest organic moiety for future applications in nanoscaled electronic devices. 相似文献
126.
Monika Szulc Justyna Samaszko-Fiertek Rafał Ślusarz Kornelia Kowalska Artur Sikorski 《Journal of carbohydrate chemistry》2016,35(3):161-171
Solid phase peptide synthesis (SPPS) of two selected muramyl pentapeptide derivatives is described. The simplicity of removing the protecting groups via one-step deprotection and cleavage from the resin is the biggest advantage of SPPS. Using this method, two muramyl pentapeptide derivatives, D-MurN3-L-Ala-D-iGlu-L-Lys-D-Ala-D-Ser (5) and D-MurN3-L-Ala-D-iGlu-L-Lys-D-Ala-D-Ala (6), were obtained. Their chemical structures were confirmed by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy. To determine the absolute configuration of the carbon atom in the side chain of the muramic acid derivative, single-crystal X-ray diffraction measurements were recorded. 相似文献
127.
High alpha/beta-anomer selectivity in molecular recognition of carbohydrates by artificial receptors
[structure: see text] New effective, acyclic, pyridine-based receptors 1-3 show remarkable alpha/beta binding selectivity in the recognition of monosaccharides. They are able to participate in cooperative and bidentate hydrogen bonds with sugar hydroxyls as well as in CH-pi interactions with CH's of sugar molecules. 相似文献
128.
We propose a conceptual framework that leads to an abstract characterization for the exact solvability of Calabi–Yau varieties in terms of abelian varieties with complex multiplication. The abelian manifolds are derived from the cohomology of the Calabi–Yau manifold, and the conformal field theoretic quantities of the underlying string emerge from the number theoretic structure induced on the varieties by the complex multiplication symmetry. The geometric structure that provides a conceptual interpretation of the relation between geometry and conformal field theory is discrete, and turns out to be given by the torsion points on the abelian varieties. 相似文献
129.
Domińska M Jackowska K Krysiński P Blanchard GJ 《The journal of physical chemistry. B》2005,109(33):15812-15821
We have synthesized and characterized a family of self-assembled monolayers containing pyrene derivatives on gold and indium-doped tin oxide (ITO) substrates. The covalently bound pyrene functionalities serve as either spectroscopic or electrochemical probes of their immediate environment, and we explore their electrochemical response in this paper. When these compounds are the only constituents bound to the interfaces, the molecules enjoy significant structural freedom. The addition of aliphatic adsorbates to the interfaces serves to place the pyrene derivatives in a more restricted environment. Cyclic voltammetry shows that the organization of a monolayer with pyrene derivatives, and the position of the terminal pyrene within such monolayer, depend sensitively on the length of the pyrene tether and the presence or absence of aliphatic interfacial species, as well as the identity of the substrate. 相似文献
130.
Shadow effects in spiral phase contrast microscopy 总被引:3,自引:0,他引:3
Recently it has been demonstrated that spatial filtering of images in microscopy with a spiral phase element in a Fourier plane of the optical path results in a strong edge enhancement of object structures. In principle the operation is isotropic, i.e., all phase edges of a sample object are highlighted simultaneously, independent of their local direction. However, here we demonstrate that the symmetry can be broken intentionally by controlling the phase of the central area of a spiral phase hologram, which is displayed at a computer controlled spatial light modulator. This produces an apparent shadow effect which can be rotated at video rate. The resulting relieflike impression of the sample topography with a longitudinal resolution in the subwavelength regime is demonstrated by imaging a standard low contrast test sample consisting of a human cheek cell. 相似文献