Search results for "graphics"
showing 10 items of 1223 documents
Ambient Art : Creative Information Representation
2007
Ambient art is the aesthetic presentation of information, using artistic techniques to achieve a pleasing image that also contains hidden depths, where exposure to it over time allows a viewer to understand something about the information sources that it represents. This paper reviews the artistic and computational background of ambient systems, and presents two case studies of systems developed by our research team, from their initial design to the experiences of the people encountering them. The first case presents a photo mosaic of images based on the news headlines coupled with a structured picture based on the weather; the second presents stylistic perspectives on activity in a public …
Fragment condensation on solid-phase in the synthesis of an amphiphilic glycopeptide from the homophilic recognition domain of epithelial cadherin 1
1998
Abstract The lipo-glycopeptide 6 containing the homophilic recognition motif of mouse epithelial cadherin 1 was synthesised via a fragment condensation on a solid phase linked peptide using an allylic anchor and a pentafluorophenol-based coupling reagent.
Model studies on a diastereoselective synthesis of the C(33)–C(37) fragment of Amphotericin B
2003
Abstract A new, short and highly diastereoselective synthetic route aiming at the C(33)–C(37) fragment of Amphotericin B has been developed. Studies with a model aldehyde (benzaldehyde) have given very promising results: the desired stereochemistry of all four stereocenters of the target molecule has been achieved with high diastereoselection. The stereochemistry of three key intermediates and the target segment has been confirmed by X-ray crystallography.
Selective protein removal and desalting using microchip CE.
2006
Abstract This paper describes the on-line sample pretreatment and analysis of proteins and peptides with a poly(methylmethacrylate) (PMMA) microfluidic device (IonChip™). This chip consists of two hyphenated electrophoresis channels with integrated conductivity detectors. The first channel can be used for sample preconcentration and sample clean-up, while in the second channel the selected compounds are separated. Isotachophoresis (ITP) combined with zone electrophoresis (CZE) was used to preconcentrate a myoglobin sample by a factor of about 65 before injection into the second dimension and to desalt a mixture of six proteins with 100 mM NaCl. However, ITP–CZE could not be used for the rem…
Theoretical studies on cycloaddition reactions
2014
Cycloaddition reactions represent one of the most powerful processes in organic chemistry. The most common types of cycloaddition reactions are the Diels-Alder (DA) and the 1,3-dipolar cycloaddition reactions (1,3-DCs) which lead to five and six membered rings, respectively. In our ongoing efforts to contribute to the understanding of DA and 1,3-DCs; we studied the following using the B3LYP/6-31G(d) level of theory: 1. The 1,3-DCs of the pyridinium-3-olates and pyrazinium-3-olates with methyl acrylate and methyl methacrylate [1,2]. 2. The competitive hetero-DA and 1,3-DCs of methyl glyoxylate oxime and its tautomeric nitrone with cyclopentadiene in the absence and in the presence of BF3 as …
GPU Based Molecular Dynamics Simulations of Polymer Rings in Concentrated Solution: Structure and Scaling
2011
We report on equilibrium properties of a concentrated solution of non-concatenated ring polymers by Molecular dynamics simulations using HooMD-blue, a fast implementation on graphics processor units (GPUs). We are able to identify the intermediate scaling regime for the radius of gyration Rg ∝ N as well as indication for a crossover to Rg ∝ N for rings with chain length N in our fully flexible off-lattice polymer model. This crossover takes place between a ring size of 2500 and 7500 monomers for monomer density ρ = 0.5. Our results are in agreement with recent studies for lattice and stiff off-lattice models and show once again that this scaling is not model dependent at all. Furthermore th…
Compressed Polymer Brushes under the Shear Flow
1998
The structure and dynamics of two compressed polymer brushes under the shear deformation were investigated by the methods of stochastic dynamics. The shear was created by the move-ment of grafting planes with the constant velo-cities in opposite directions along the planes.
Adsorption of Oligomers and Polymers into a Polymer Brush Formed from Grafted Ring Polymers
2013
The interaction of a ring polymer brush with a solution containing oligomers or free linear flexible macromolecules is studied by Monte Carlo simulation, varying the chain length of the free chains, and in selected cases also the lengths of the rings. Two grafting densities are studied, corresponding to semidilute and very concentrated conditions, and a comparison with the corresponding case of brushes formed from grafted linear chains is made. Although the ring polymer linear dimensions in the brushes show an anomalous scaling with ring length, similar to (noncatenated) ring polymer melts, the concentration profiles of oligomers and long macromolecules in ring polymer brushes differ only v…
Brownian dynamics simulation of grafted polymer brushes
1995
We present results of computer simulations by the method of Brownian dynamics of polymeric brushes attached to impenetrable planes. For testing both model and method we have used one polymer brush attached to a repulsive plane and compare some results with Monte Carlo results of Lai and Binder on the bond fluctuation model. We have also studied two polymeric brushes attached to two parallel planes at different distances between planes, and investigate the interplay between the interpenetration of the brushes and the configurational properties of the grafted chains.
How does the pattern of grafting points influence the structure of one-component and mixed polymer brushes?
2005
Using Monte Carlo simulations of a coarse-grained bead-spring model we study the lateral structure formation of one-component polymer brushes in a bad solvent and of a mixed polymer brush upon increasing the incompatibility of the two species. We compare the morphology of the brush with a regular distribution of grafting points and with a random arrangement. Density or composition fluctuations of the grafting points enhance the formation of irregular structures but randomness prevents the formation of long-range order. Even small fluctuations of the grafting points are sufficient to pin the lateral structures of the brush.