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- ItemMini-Workshop: Gibbs Measures for Nonlinear Dispersive Equations(Zürich : EMS Publ. House, 2018) Schlein, Benjamin; Sohinger, VedranIn this mini-workshop we brought together leading experts working on the application of Gibbs measures to the study of nonlinear PDEs. This framework is a powerful tool in the probabilistic study of solutions to nonlinear dispersive PDEs, in many ways alternative or complementary to deterministic methods. Among the special topics discussed were the construction of the measures, applications to dynamics, as well as the microscopic derivation of Gibbs measures from many-body quantum mechanics.
- ItemAn asymptotic analysis for a generalized Cahn--Hilliard system with fractional operators(Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2020) Colli, Pierluigi; Gilardi, Gianni; Sprekels, JürgenIn a recent paper the same authors have proved existence, uniqueness and regularity results for a class of viscous and nonviscous Cahn--Hilliard systems of two operator equations in which nonlinearities of double-well type, like regular or logarithmic potentials, as well as nonsmooth potentials with indicator functions, were admitted. The operators appearing in the system equations are fractional powers in the spectral sense of general linear operators, which are densely defined, unbounded, selfadjoint, and monotone in the Hilbert space of square-integrable functions on a bounded and smooth three-dimensional domain, and have compact resolvents. Here, for the case of the viscous system, we analyze the asymptotic behavior of the solution as the fractional power coefficient of the second operator tends to zero. We prove convergence to a phase relaxation problem at the limit, and we also investigate this limiting problem, in which an additional term containing the projection of the phase variable on the kernel of the second operator appears.
- ItemSpectral surface albedo over Morocco and its impact on radiative forcing of Saharan dust(Abingdon : Taylor & Francis, 2009) Bierwirth, E.; Wendisch, M.; Ehrlich, A.; Heese, B.; Tesche, M.; Althausen, D.; Schladitz, A.; Müller, D.; Otto, S.; Trautmann, T.; Dinter, T.; Von Hoyningen-Huene, W.; Kahn, R.In May-June 2006, airborne and ground-based solar (0.3-2.2 μm) and thermal infrared (4-42 μm) radiation measurements have been performed in Morocco within the Saharan Mineral Dust Experiment (SAMUM). Upwelling and downwelling solar irradiances have been measured using the Spectral Modular Airborne Radiation Measurement System (SMART)-Albedometer. With these data, the areal spectral surface albedo for typical surface types in southeastern Morocco was derived from airborne measurements for the first time. The results are compared to the surface albedo retrieved from collocated satellite measurements, and partly considerable deviations are observed. Using measured surface and atmospheric properties, the spectral and broad-band dust radiative forcing at top-of-atmosphere (TOA) and at the surface has been estimated. The impact of the surface albedo on the solar radiative forcing of Saharan dust is quantified. In the SAMUM case of 19 May 2006, TOA solar radiative forcing varies by 12 W m-2 per 0.1 surface-albedo change. For the thermal infrared component, values of up to +22 W m-2 were derived. The net (solar plus thermal infrared) TOA radiative forcing varies between -19 and +24 W m-2 for a broad-band solar surface albedo of 0.0 and 0.32, respectively. Over the bright surface of southeastern Morocco, the Saharan dust always has a net warming effect. © 2008 The Author Journal compilation © 2008 Blackwell Munksgaard.
- ItemNew Trends in Boundary Elements(Oberwolfach-Walke : Mathematisches Forschungsinstitut Oberwolfach, 2002) Schwab, Christoph; Stephan, Ernst P.; Wendland, Wolfgang L.[no abstract available]
- ItemMicrofluidic colloid filtration([London] : Macmillan Publishers Limited, part of Springer Nature, 2016) Linkhorst, John; Beckmann, Torsten; Go, Dennis; Kuehne, Alexander J. C.; Wessling, MatthiasFiltration of natural and colloidal matter is an essential process in today’s water treatment processes. The colloidal matter is retained with the help of micro- and nanoporous synthetic membranes. Colloids are retained in a “cake layer” – often coined fouling layer. Membrane fouling is the most substantial problem in membrane filtration: colloidal and natural matter build-up leads to an increasing resistance and thus decreasing water transport rate through the membrane. Theoretical models exist to describe macroscopically the hydrodynamic resistance of such transport and rejection phenomena; however, visualization of the various phenomena occurring during colloid retention is extremely demanding. Here we present a microfluidics based methodology to follow filter cake build up as well as transport phenomena occuring inside of the fouling layer. The microfluidic colloidal filtration methodology enables the study of complex colloidal jamming, crystallization and melting processes as well as translocation at the single particle level.
- ItemSpatial Random Processes and Statistical Mechanics(Zürich : EMS Publ. House, 2006) Biskup, Marek; van der Hofstad, Remco; Sidoravicius, VladasThe workshop focused on the broad area of spatial random processes and their connection to statistical mechanics. The subjects of interest included random walk in random environment, interacting random walks, polymer models, random fields and spin systems, dynamical problems, metastability as well as problems involving two-dimensional conformal geometry. The workshop brought together many leading researchers in these fields who reported to each other on their recent achievements and exchanged ideas for new problems and potential solutions.
- ItemMini-Workshop: Anisotropic Motion Laws(Zürich : EMS Publ. House, 2006) Smereka, Peter; Voigt, AxelAnisotropic motion laws play a key role in many applications ranging from materials science, biophysics to image processing. All these highly diversified disciplines have made it necessary to develop common mathematical foundations and framworks to deal with anisotropy in geometric motion. The workshop brings together leading experts from various fields to address well-posedness, accuracy, and computational efficiency of the mathematical models and algorithms.
- ItemMethyl 5-chloro-2-hydr-oxy-3-(4-methoxyphenyl)-4,6-dimethylbenzoate(Chester : International Union of Crystallography, 2009) Adeel, M.; Ali, I.; Langer, P.; Villinger, A.In the title compound, C17H17ClO4, the dihedral angle between the mean planes of the two benzene rings is 65.92 (5)°. The methyl ester group lies within the ring plane [deviations of O atoms from the plane = -0.051 (2) and 0.151 (2) Å] due to an intra-molecular O - H⋯O hydrogen bond. In the crystal, molecules are held together by rather weak non-classical inter-molecular C - H⋯O hydrogen bonds, resulting in dimeric units about inversion centers, forming eight- and ten-membered ring systems as R22(8) and R2 2(10) motifs. © Adeel et al. 2009.
- ItemRing-Closure Mechanisms Mediated by Laccase to Synthesize Phenothiazines, Phenoxazines, and Phenazines(Washington, DC : ACS Publications, 2020) Hahn, Veronika; Mikolasch, Annett; Weitemeyer, Josephine; Petters, Sebastian; Davids, Timo; Lalk, Michael; Lackmann, Jan-Wilm; Schauer, FriederThe green and environmentally friendly synthesis of highly valuable organic substances is one possibility for the utilization of laccases (EC 1.10.3.2). As reactants for the herein described syntheses, different o-substituted arylamines or arylthiols and 2,5-dihydroxybenzoic acid and its derivatives were used. In this way, the formation of phenothiazines, phenoxazines, and phenazines was achieved in aqueous solution mediated by the laccase of Pycnoporus cinnabarinus in the presence of oxygen. Two types of phenothiazines (3-hydroxy- and 3-oxo-phenothiazines) formed in one reaction assay were described for the first time. The cyclization reactions yielded C–N, C–S, or C–O bonds. The syntheses were investigated with regard to the substitution pattern of the reaction partners. Differences in C–S and C–N bond formations without cyclization are discussed.
- Item[1-Dimethylsilyl-2-phenyl-3-(η5-tetramethylcyclopentadienyl) prop-1-en-1-ylκC1](n5-pentamethylcyclopentadienyl)- titanium(III)(Chester : International Union of Crystallography, 2009) Lamač, M.; Spannenberg, A.; Arndt, P.; Rosenthal, U.The title compound, [Ti(C10H15)(C20H 26Si)], was obtained from the reaction of [Ti{5: 1-C5Me4(CH2)}(5-C 5Me5)] with the alkynylsilane PhC2SiMe 2H. The complex crystallizes with two independent mol-ecules in the asymmetric unit, which differ in the conformation of the propenyl unit, resulting in their having opposite helicity. No inter-molecular inter-actions or inter-actions involving the Si- H bond are present. The observed geometrical parameters are unexceptional compared to known structures of the same type.