87 research outputs found
Calorons in SU(3) lattice gauge theory
We examine the semiclassical content of SU(3) Yang Mills theory on the
lattice at finite temperature. Employing the cooling method, a set of classical
fields is generated from a Monte Carlo ensemble. Various operators are used to
inspect this set with respect to topological properties. We find pseudoparticle
fields, so-called caloron solutions, possessing the remarkable features of
(superpositions of) Kraan-van Baal solutions, i.e. extensions of
Harrington-Shepard calorons to generic values of the holonomy.Comment: 14 pages, 16 figure
Gradient structures for flows of concentrated suspensions
In this work we investigate a two-phase model for concentrated suspensions. We construct a PDE formulation using a gradient flow structure featuring dissipative coupling between fluid and solid phase as well as different driving forces. Our construction is based on the concept of flow maps that also allows it to account for flows in moving domains with free boundaries. The major difference compared to similar existing approaches is the incorporation of a non-smooth two-homogeneous term to the dissipation potential, which creates a normal pressure even for pure shear flows
Calorons with non-trivial holonomy on and off the lattice
We discuss recent solutions for SU(2) calorons with non-trivial holonomy at
higher charge, both through analytic means and using cooling, as well as
extensive lattice studies for SU(3).Comment: 12 pages, 16 figures in 34 parts, 4 talks presented at Lattice
2004(topology
Modeling of Edge-Emitting Lasers Based on Tensile Strained Germanium Microstrips
In this paper, we present a thorough modeling of an edge-emitting laser based on strained germanium (Ge) microstrips. The full-band structure of the tensile strained Ge layer enters the calculation of optical properties. Material gain for strained Ge is used in the 2D simulation of the carrier transport and of the optical field within a cross section of the microstrips orthogonal to the optical cavity. We study optoelectronic properties of the device for two different designs. The simulation results are very promising as they show feasible ways toward Ge emitter devices with lower threshold currents and higher efficiency as published insofar
Pharmaceutical Formulation Facilities as Sources of Opioids and Other Pharmaceuticals to Wastewater Treatment Plant Effluents
Facilities involved in the manufacture of pharmaceutical products are an under-investigated source of pharmaceuticals to the environment. Between 2004 and 2009, 35 to 38 effluent samples were collected from each of three wastewater treatment plants (WWTPs) in New York and analyzed for seven pharmaceuticals including opioids and muscle relaxants. Two WWTPs (NY2 and NY3) receive substantial flows (>20% of plant flow) from pharmaceutical formulation facilities (PFF) and one (NY1) receives no PFF flow. Samples of effluents from 23 WWTPs across the United States were analyzed once for these pharmaceuticals as part of a national survey. Maximum pharmaceutical effluent concentrations for the national survey and NY1 effluent samples were generally <1 ÎĽg/L. Four pharmaceuticals (methadone, oxycodone, butalbital, and metaxalone) in samples of NY3 effluent had median concentrations ranging from 3.4 to >400 ÎĽg/L. Maximum concentrations of oxycodone (1700 ÎĽg/L) and metaxalone (3800 ÎĽg/L) in samples from NY3 effluent exceeded 1000 ÎĽg/L. Three pharmaceuticals (butalbital, carisoprodol, and oxycodone) in samples of NY2 effluent had median concentrations ranging from 2 to 11 ÎĽg/L. These findings suggest that current manufacturing practices at these PFFs can result in pharmaceuticals concentrations from 10 to 1000 times higher than those typically found in WWTP effluents
Tailoring drug release profile of low-molecular-weight hydrogels by supramolecular co-assembly and thiol–ene orthogonal coupling
Cellular Uptake of Cationic Polymer-DNA Complexes Via Caveolae Plays a Pivotal Role in Gene Transfection in COS-7 Cells
Multi-dimensional modeling and simulation of semiconductor nanophotonic devices
Self-consistent modeling and multi-dimensional simulation of semiconductor nanophotonic devices is an important tool in the development of future integrated light sources and quantum devices. Simulations can guide important technological decisions by revealing performance bottlenecks in new device concepts, contribute to their understanding and help to theoretically explore their optimization potential. The efficient implementation of multi-dimensional numerical simulations for computer-aided design tasks requires sophisticated numerical methods and modeling techniques. We review recent advances in device-scale modeling of quantum dot based single-photon sources and laser diodes by self-consistently coupling the optical Maxwell equations with semiclassical carrier transport models using semi-classical and fully quantum mechanical descriptions of the optically active region, respectively. For the simulation of realistic devices with complex, multi-dimensional geometries, we have developed a novel hp-adaptive finite element approach for the optical Maxwell equations, using mixed meshes adapted to the multi-scale properties of the photonic structures. For electrically driven devices, we introduced novel discretization and parameter-embedding techniques to solve the drift-diffusion system for strongly degenerate semiconductors at cryogenic temperature. Our methodical advances are demonstrated on various applications, including vertical-cavity surface-emitting lasers, grating couplers and single-photon sources
Equipment for adhesive bonding
This chapter describes the equipment required for manual adhesive bonding processes. For some readers, the comments about equipment may seem trivial, but they are important as nonobservance of these points can in practice lead to flawed bonded joints. The individual components which make up mixing and dosing systems have been described and their special features outlined in an attempt to quantify the hitherto qualitative descriptions that have prevailed in the literature. Thereafter, some basics of automation and robotics are outlined with a special excursion on the topic parameters affecting accuracy. Terminal opportunities of accelerated curing are explained using the examples of UV radiation and inductive heating
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