Über Einige Eigenschaften der Kommutatoren der Symmetrischen Halgruppe

Ohne ZusammenfassungDie Forschungsarbeit wurde mit Unterstützung der Alexander von Humboldt-Stiftung durchgeführt.     

[(4,4‐Dimethyl‐2‐oxo‐1,3‐oxazolidin‐3‐yl)methyl]phosphonic acid

The title compound, C₆H₁₂NO₅P, was synthesized as an inter­mediate phase in a search for new N‐(phosphono­methyl)glycine derivatives. The mol­ecules are held together by O—H⋯O hydrogen bonds, forming chains along the b axis in the crystal structure. The observed mol­ecular structure is compared with that calculated by the density functional theory method.     

Magneto-Galvanic Resonances in Hollow Cathode Discharge Lamps

The galvanic behavior of a hollow cathode discharge versus an external weak magnetic field is investigated. The application of this field leads to disordering of the self-aligned states, which is detected as a resonance in the discharge current, named the magneto-galvanic signal. A correlation magneto-galvanic signal–operating voltage-current point is established and attributed to Penning ionization. The contribution of the metastable Ne I 1 s₅ to the magneto-galvanic resonance is also verified.     

Zero Modes’ Fusion Ring and Braid Group Representations for the Extended Chiral <Emphasis Type="Italic">su</Emphasis>(2) WZNW Model

A zero modes’ Fock space is constructed for the extended chiral WZNW model. It gives room to a realization of the fusion ring of representations of the restricted quantum universal enveloping algebra at an even root of unity, and of its infinite dimensional extension by the Lusztig operators We provide a streamlined derivation of the characteristic equation for the Casimir invariant from the defining relations of A central result is the characterization of the Grothendieck ring of both and in Theorem 3.1. The properties of the fusion ring in are related to the braiding properties of correlation functions of primary fields of the conformal current algebra model.      

Manganese-enhanced magnetic resonance microscopy of mineralization

Paramagnetic manganese (II) can be employed as a calcium surrogate to sensitize magnetic resonance microscopy (MRM) to the processing of calcium during bone formation. At high doses, osteoblasts can take up sufficient quantities of manganese, resulting in marked changes in water proton T(1), T(2) and magnetization transfer ratio values compared to those for untreated cells. Accordingly, inductively coupled plasma mass spectrometry (ICP-MS) results confirm that the manganese content of treated cell pellets was 10-fold higher than that for untreated cell pellets. To establish that manganese is processed like calcium and deposited as bone, calvaria from the skull of embryonic chicks were grown in culture medium supplemented with 1 mM MnCl(2) and 3 mM CaCl(2). A banding pattern of high and low T(2) values, consistent with mineral deposits with high and low levels of manganese, was observed radiating from the calvarial ridge. The results of ICP-MS studies confirm that manganese-treated calvaria take up increasing amounts of manganese with time in culture. Finally, elemental mapping studies with electron probe microanalysis confirmed local variations in the manganese content of bone newly deposited on the calvarial surface. This is the first reported use of manganese-enhanced MRM to study the process whereby calcium is taken up by osteoblasts cells and deposited as bone.     

Thermal properties and the structure of amorphous Sb2Se3 thin film

The amorphous Sb₂Se₃ film with a thickness ~0.9 µm was prepared by thermal evaporation and its composition was confirmed using an energy-dispersive X-ray analysis. The amorphous state was checked by an X-ray diffraction analysis. The optical gap E _g ^opt was determined to be 1.32 eV. The glass transition temperature could not be found by either a differential scanning calorimetry or a thermomechanical analysis. The film was crystallized and characterized using the quasi-isothermal method. The temperature dependence of the isobaric heat capacity was raised monotonously and no drop over the course of the crystallization was observed. The temperature-modulated thermomechanical analysis determined a temperature T = 133 °C which can be assumed to be the temperature of the structural reorganization beginning. Raman spectra of amorphous Sb₂Se₃ revealed that the vibrations of both the amorphous and crystalline phase are close to one other. Raman scattering revealed that both the short and the medium-range order of amorphous and crystalline phases are similar.     

Extended U(1) Conformal Field Theories and Zk-Parafermions

A constructive approach is developed for studying local chiral algebras generated by a pair of oppositely charged fields Ψ (z, ±g) such that the operator product expansion (OPE) of Ψ(z₁, g) Ψ(z₂, −g) involves a U(1) current. The main tool in the study is the factorization property of the charged fields (exhibited in [PT 2, 3]) for Virasoro central charge c < 1 into U(1)-vertex operators tensored with ZAMOLODCHIKOV-FATEEV [ZF1] (generalized) Z_k-parafermions. The case Δ₂ = 4 (Δ₁ − 1), where Δ_v = Δ_k−v(Δ₀ = 0) are the conformaldimensions of the parafermionic currents, is studied in detail. For Δ_v = 2v(1 − v/k) the theory is related to GEPNER'S [Ge] Z₂ [so (k)] parafermions and the corresponding quantum field theoretic (QFT) representations of the chiral algebra are displayed. The Coulomb gas method of [CR] is further developed to include an explicit construction of the basic parafermionic current Ψ of weight Δ = Δ₁. The characters of the positive energy representations of the local chiral algebra are written as sums of products of Kac's string functions and classical θ-functions.     

Polarization reflection holographic gratings in azobenzene-containing gelatine films

We have written polarization reflection holograms in an azobenzene-containing material. Two waves with circular polarization were used to record the gratings; the light resulting from their overlap induces chirality in the samples. The holographic reflection of the polarization gratings has the properties of Bragg reflection in cholesteric liquid crystals.     

Photoinduced dichroism in lightsensitive suspension layers of As2S3 dispersed in gelatin

The absorption edge shift and the spectra of the dichroism in suspension layers of As₂S₃ dispersed in gelatin induced by a linearly polarized laser light are measured. The results are compared to the photoinduced changes in evaporated As₂S₃ layers.