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- ItemCrystal structure of (2S,4S,7S)-7,7-dichloro-4-(1-chloro-1-methylethyl)-1- (2,2,2-trichloroethyl)bicyclo[4.1.0]heptane, C12H16Cl 6(Berlin : de Gruyter, 2009) Boualy, B.; el Firdoussi, L.; Ali, M.A.; Karim, A.; Spannenberg, A.C12H16Cl6, orthorhombic, P2 12121 (no. 19), a = 6.0742(3) Å, b = 9.7189(6) Å, c = 26.700(1) Å, V = 1576.2 Å3, Z = 4, Rgt(F) = 0.019, wRref(F2) = 0.045, T= 200 K. © by Oldenbourg Wissenschaftsverlag.
- ItemArbeitsgemeinschaft mit aktuellem Thema: Polylogarithms(Zürich : EMS Publ. House, 2004) Kings, Guido; Wildeshaus, Jörg[no abstract available]
- ItemThe Mathematical, Computational and Biological Study of Vision(Oberwolfach-Walke : Mathematisches Forschungsinstitut Oberwolfach, 2001) von der Malsburg, Christoph; Mumford, David[no abstract available]
- ItemAdaptive Numerical Methods for PDEs(Zürich : EMS Publ. House, 2007) Süli, Endre; Verfürth, RüdigerThis collection contains the extended abstracts of the talks given at the Oberwolfach Conference on “Adaptive Numerical Methods for PDEs”, June 10th - June 16th, 2007. These talks covered various aspects of a posteriori error estimation and mesh as well as model adaptation in solving partial differential equations. The topics ranged from the theoretical convergence analysis of self-adaptive methods, over the derivation of a posteriori error estimates for the finite element Galerkin discretization of various types of problems to the practical implementation and application of adaptive methods.
- ItemApplications of Asymptotic Analysis(Zürich : EMS Publ. House, 2006) Palencia, E. Sanchez; Sokolowski, Jan; Wagner, BarbaraThis workshop focused on asymptotic analysis and its fundamental role in the derivation and understanding of the nonlinear structure of mathematical models in various fields of applications, its impact on the development of new numerical methods and on other fields of applied mathematics such as shape optimization. This was complemented by a review as well as the presentation of some of the latest developments of singular perturbation methods.
- ItemPositivität von Polynomen(Oberwolfach-Walke : Mathematisches Forschungsinstitut Oberwolfach, 2002) Berg, Christian; Prestel, Alexander[no abstract available]
- ItemAdvanced batch house technology for float glass - the new plant of SAINT-GOBAIN GLASS DEUTSCHLAND in Cologne/Porz(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2002) Drescher, Holger[no abstract available]
- ItemArbeitsgemeinschaft: Percolation(Zürich : EMS Publ. House, 2007) van den Berg, Jacob; Camia, FedericoAbstract. Percolation as a mathematical theory is more than fifty years old. During its life, it has attracted the attention of both physicists and mathematicians. This is due in large part to the fact that it represents one of the simplest examples of a statistical mechanical model undergoing a phase transition, and that several interesting results can be obtained rigorously. In recent years the interest in percolation has spread even further, following the introduction by Oded Schramm of the Schramm-Loewner Evolution (SLE) and a theorem by Stanislav Smirnov showing the conformal invariance of the continuum scaling limit of two-dimensional critical percolation. These results establish a new, powerful and mathematically rigorous, link between lattice-based statistical mechanical models and conformally invariant models in the plane, studied by physicists under the name of Conformal Field Theory (CFT). The Arbeitsgemeinschaft on percolation has attracted more than thirty participants, most of them young researchers, from several countries in Europe, North America, and Brazil. The main focus has been on recent developments, but several classical results have also been presented.
- ItemEstimation of liquidus temperatures in silicate glasses(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2001) Karlsson, Kaj H.; Backman, Rainer; Cable, Michael; Peelen, Jan; Hermans, JanTwo models for estimating liquidus temperature from composition are presented and compared with thermodynamically calculated temperature as well as primary phase. Α simple polynomial model is given for high silica glasses, while a model covering a wide composition range and several primary phase fields is more complex. Thermodynamic calculations generally give too high liquidus temperatures in the devitrite field and too low in the primary field for Na2O · 2 CaO · 3 SiO2. In the wollastonite field the values are scattered, but in general too high.
- ItemUV light induced photoreduction in phosphate and fluoridephosphate glasses doped with Ni2+, Ta5+, Pb2+, and Ag+ compounds(Offenbach : Verlag der Deutschen Glastechnischen Gesellschaft, 2004) Möncke, Doris; Ehrt, DorisThe photoreduction of polyvalent ions was studied in high purity fluoride-phosphate and metaphosphate glasses doped with Ni2+ (3d8), Ta5+ (5d0), Pb2+ (6d2), and Ag+ (3d10). Compared to the undoped base glasses all doped samples display different electronic transitions in the UV at the irradiation wavelength. Glass samples containing 50 to 5000 ppm dopants were irradiated with excimer lasers at 193 and 248 nm, respectively. The subsequent defect centers, formed at ppm levels, were characterized by EPR and optical UV-VIS spectroscopy. The observed laser induced transmission losses in the UV and visible range increased in the order Ni, Ta, Pb to Ag. Extrinsic electron centers are formed by photoreduction of the dopants. (Ni2+)- is characterized by an optical transition with a maximum at 355 nm and an EPR signal around g ≈ 2.07. The maxima of the optical transitions of the (Pb2+)- -EC are positioned at 395 and 500 nm, of the (Ta5+)- -EC at 465 nm. The photoionization products of silver depend strongly on the silver concentration. At a silver content of 50 ppm only the (Ag+)- -EC is formed, visible in the optical spectra with a maximum around 450 nm. Α second silver species, (Ag+)2 -, which absorbs at 305 nm, is additionally observed in the sample doped with a silver concentration of 500 ppm. In the sample doped with 5000 ppm silver a third defect, the photooxidized (Ag+)+ -HC, with an optical band maximum at 405 nm and an EPR signal around g ≈ 2.3 is observed as well. The formation of extrinsic electron centers causes in all glasses an increase in the formation of intrinsic hole centers and often a decrease in the formation of intrinsic electron centers. Defect generation curves show that a very rapid darkening in the glasses is initiated by the addition of any of these dopants. The recovery rates of the defeets formed depend strongly on the dopant, not on the glass matrix.