Technische Universität Berlin

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Recent Submissions
Remarks on thermodynamical terminology

Muschik, Wolfgang (2004)

Often difficulties in understanding thermodynamics arise from using different terminology or semantics. Therefore here some few remarks are made for tending towards a unified thermodynamical terminology.

Thermodynamic interaction between two discrete systems in non-equilibrium

Muschik, Wolfgang ; Berezovski, Arkadi (2004)

A systematic description of the interaction between two systems is presented within the framework of thermodynamics of discrete systems. We distinguish between two situations: a contact between an equilibrium system and a non-equilibrium one, and a contact between two non-equilibrium systems. In the second case the state space includes replacement quantities, which reduce the situation to a con...

Mesoscopic theory of liquid crystals

Muschik, Wolfgang ; Papenfuss, Christina ; Ehrentraut, Harald (2004)

Liquid crystals of uniaxial and biaxial molecules are considered in the framework of the mesoscopic description which is a general tool of continuum theory. A mesoscopic theory introduces the fields beyond hydrodynamics as additional variables of a configuration space, called mesoscopic space, on which the fields appearing in balances are defined. Besides the mesoscopic space, a mesoscopic dist...

Intrusion Detection in Unlabeled Data with Quarter-sphere Support Vector Machines

Laskov, Pavel ; Schäfer, Christin ; Kotenko, Igor ; Müller, Klaus-Robert (2004)

The anomaly detection methods are receiving growing attention in the intrusion detection community. The two main reasons for this are their ability to handle large volumes of unlabeled data and to detect previously unknown attacks. In this contribution we investigate the application of a modern machine learning technique – one-class Support Vector Machines (SVM) – for anomaly detection in unlab...

New Products of Defense Secretion in South East Asian Whip Scorpions (Arachnida: Uropygi: Thelyphonida)

Haupt, Joachim ; Müller, Frank (2004)

Secretion products from the opisthosomal defense gland of south east Asian whip scorpions were identified for the first time by gas-chromatography and mass-spectrometry. Specimens of the genera Hypoctonus, Typopeltis and Ginosigma were tested. While some ingredients are present in large concentrations, others are possibly only side products and may be synthesized more incidentally. For this rea...

Self-Management – Potentiale, Probleme, Perspektiven

Herrmann, Klaus ; Mühl, Gero ; Geihs, Kurt (2004)

Gordon Moores Gesetz vom exponentiellen Wachstum der Transistordichte pro Quadrat-Zoll hat seit 1965 die IT-Industrie geprägt. Mit der damit einhergehenden Explosion der Rechnerleistung wurde die Software immer leistungsfähiger, und man ist dazu übergegangen, Rechnersysteme zu vernetzen und Anwendungen zu verteilen. Eine Folge dieser Entwicklungen ist die rapide zunehmende Komplexität der moder...

Fragmentable Heterogeneous Cocatalysts for the Metallocene-Catalyzed Polymerization of Olefins, I. Surface Modification of Silica and Characterization of the Resulting Carriers

Schumann, Herbert ; Widmaier, Ralf ; Lange, Katharina C. H. ; Wassermann, Birgit C. (2005)

Surface modification of pre-dried spherical silica nano-particles with diameters of 235 nm and 10 to 20 nm and of commercially available non-spherical silica materials using various aminoalkyltrialkoxysilanes and α-ω-bis(alkoxysilyl)organyls (organyl = alkanediyl, aminoalkanediyl, polyether, polysiloxane) has been performed in suspension in solvents with water. The quantity of water has a domin...

Fragmentable Heterogeneous Cocatalysts for the Metallocene-Catalyzed Polymerization of Olefins, II [1]. Preparation, Characterization and Testing of the Cocatalysts and Microscopic Evaluation of the Polyethylene

Schumann, Herbert ; Widmaier, Ralf ; Lange, Katharina C. H. ; Wassermann, Birgit C. (2005)

Surface modified silica were reacted with different aluminiumalkyls AlR2R’ (R = Me, Et, i-Bu, R’ = H, Me, Et, i-Bu), oligomeric methylaluminoxane (MAO) and combinations of both, to yield heterogeneous cocatalysts. These cocatalyts were employed to polymerize ethylene using zirconocene dichloride as the catalyst. The polymerization activity profiles have been recorded and compared with the infor...

2,5-Dimethyl-3,6-bis[(2,6-diisopropylphenylimino)methyl]- and 2,6-Bis[(2,6-diisopropylphenylimino)methyl]pyrazine: Two New Chelating Ligands for Transition Metal Complexes

Schumann, Herbert ; Luo, He-Kuan (2005)

The reaction of tetramethylpyrazine with SeO2 yields 2,5-dimethylpyrazine-3,6-dicarboxaldehyde (1) from which the 2,5-dimethyl-3,6-bis[(2,6-diisopropylphenylimino)methyl]pyrazine (2) was synthesized by treatment with 2 equivalents of 2,6-diisopropylaniline. 2,6-Dimethylpyrazine reacts with benzaldehyde to give 2,6-distyrylpyrazine (3). Ozonolysis of 3, followed by treatment with Na2SO3 and 2,6-...

Di-, Hexa- und Deca-substituierte Decaphenylferrocene

Schumann, Herbert ; Sühring, Klaudia (2005)

5-Bromo-1,2,3,4-tetraphenyl-5-p-tolyl-1,3-cyclopentadiene (1a), 5-Bromo-1,4-di-phenyl-2,3,5- tri-p-tolyl-1,3-cyclopentadiene (1b), 5-Bromo-1,2,3,4,5-penta-p-tolyl-1,3-cyclopentadiene (1c), 5- Bromo-1,2,3,4-tetraphenyl-5-p-bromophenyl-1,3-cyclopentadiene (1d), and 5-Bromo-1,2,3,4-tetraphenyl- 5-p-anisyl-1,3-cyclopentadiene (1e) react with ironpentacarbonyl in m-xylene to yield the corresponding ...

Metallkomplexe von 2,2’-Dipyridyldisulfid mit Quecksilber(II)-, Cadmium(II)- und Zink(II)-Halogeniden und mit Cadmium(II)- Trifluormethansulfonat

Pickardt, Joachim ; Chrzanowski, Lars von ; Steudel, Ralf ; Borowski, Marina ; Beck, Sebastian (2005)

Crystals of diiodo-2,2’-dipyridyldisulfide mercury(II) [HgI2(C5H4N)2S2], dichloro-2,2’-dipyridyldisulfide zinc(II) [ZnCl2(C5H4N)2S2], dibromo-2,2’-dipyridyldisulfide cadmium(II) [CdBr2 (C5H4N)2S2], diiodo-2,2’-dipyridyldisulfide cadmium(II) [CdI2(C5H4N)2S2], and diaquo 2,2’-dipyridyldisulfide cadmium(II) trifluoromethanesulfonate [Cd(H2O)2(C5H4N)2S2](CF3SO3)2, were obtained by evaporation of so...

Studies on the Thermolysis of Ether-Stabilized Lu(CH2SiMe3)3. Molecular Structure of Lu(CH2SiMe3)3(THF)(diglyme)

Rufanov, Konstantin A. ; Freckmann, Dominique M. M. ; Kroth, Heinz-Jürgen ; Schutte, Stefan ; Schumann, Herbert (2005)

Lu(CH2SiMe3)3(THF)2 (2) decomposes slowly at room temperature with formation of Me4Si. In order to understand the mechanism of this elimination process, Lu(CH2SiMe3)3([D8]-THF)2 (1), Lu(CH2SiMe3)3(THF)(DME) (3), and Lu(CH2SiMe3)3(THF)(diglyme) (4) were prepared. The results of 1H NMR spectroscopic studies of the decomposition in solution exclude an α- as well as a β -H elimination mechanism and...

Deca(4-methylbenzyl)ferrocen und -stannocen

Schumann, Herbert ; Sühring, Klaudia ; Weimann, Roman ; Hummert, Markus (2005)

Cyclopentadiene reacts with five equivalents of 4-methylbenzylalcohol (1:5,6 mole ratio) and sodium yielding penta(4-methylbenzyl)cyclopenta-2,4-diene (1), which upon treatment with butyl lithium affords the lithium salt [(4-MeC6H4CH2)5C5]Li (2). The reactions of 2 with FeCl2 and SnCl2 result in the formation of deca(4-methylbenzyl)ferrocene (3) and deca(4-methylbenzyl)stannocene (4), respectiv...

Flow Velocity and Effective Viscosity of a Fluid Containing Rigid Cylindrical Inclusions

Hess, Siegfried (2005)

The determination of the flow properties of a fluid containing a cylindrical inclusion with its long axis oriented parallel to the vorticity direction is a 2-dimensional problem which is treated as a special case in a calculation of the corresponding D-dimensional problem. The velocity and pressure are obtained from the solution of the equations of hydrodynamics where D-dimensional multipole po...

Close-to-Fourier heat conduction equation of solids of constant mass density

Muschik, Wolfgang ; Siebert, Jürgen ; Herrmann, Heiko ; Rückner, Gunnar (2005)

Heat conduction close-to-Fourier means that we look for a minimal extension of heat conduction theory using the usual Fourier expression of the heat flux density and modifying that of the internal energy as minimally as possible by choosing the minimal state space. Applying Liu's procedure results in the class of materials and a dierential equation both belonging to the close-to-Fourier case of...

A mesoscopic approach to diffusion phenomena in mixtures

Palumbo, Nunzia ; Papenfuss, Christina ; Rogolino, Patrizia (2005)

The mesoscopic concept is applied to the theory of mixtures. The aim is to investigate the diusion phenomenon from a mesoscopic point of view. The domain of the field quantities is extended by the set of mesoscopic variables, here the velocities of the components. Balance equations on this enlarged space are the equations of motion for the mesoscopic fields. Moreover, local distribution functio...

Ein neues Verfahren zur patientenorientierten Zuordnung von Rollstuhlsitzkissen auf Basis von standardisierten Prüfverfahren

Diesing, Peter ; Hochmann, David ; Boenick, Ulrich ; Kraft, Marc (2005)

Rollstuhlsitzkissen sind die Schnittstelle zwischen Rollstuhl und Rollstuhlfahrer und übernehmen dabei Last übertragende und stabilisierende Aufgaben. Zusätzlich sollen sie helfen, Druckgeschwüre durch mechanische Entlastung und einen Abtransport von Feuchtigkeit und Wärme zu vermeiden. Die Auswahl eines Sitzkissen erfolgt dabei häufig anhand einer subjektiven Einschätzung der Sitzkisseneigensc...

Supraconvergence of a Finite Difference Scheme for Elliptic Boundary Value Problems of the Third Kind in Fractional Order Sobolev Spaces

Emmrich, Etienne ; Grigorieff, Rolf Dieter (2006)

In this paper, we study the convergence of the finite difference discretization of a second order elliptic equation with variable coefficients subject to general boundary conditions. We prove that the scheme exhibits the phenomenon of supraconvergence on nonuniform grids, i.e., although the truncation error is in general of the first order alone, one has second order convergence. All error esti...

Introduction of Substituents on the 2-Oxo-piperazine Skeleton by [3+2] Cycloaddition and Subsequent Transformation

Wierschem, Frank ; Rück-Braun, Karola (2006)

The 3,4-substituted 2-oxo-piperazines 5 - 9 are obtained by [3+2] cycloaddition from nitrone 1 and a variety of alkenes. Subsequent functionalization of the bicyclic adducts involves reductive N-O bond cleavage. A route towards libraries of immobilized 1,3-aminoalcohols with a 3,4-substituted 2-oxo-piperazine scaffold is briefly discussed for adducts derived from N-substituted maleic imides

Vertical Governance between Airlines and Airports - A Transaction Cost Analysis

Fuhr, Johannes ; Beckers, Thorsten (2006)

With airport privatization and infrastructure expansion projects taking place in the liberalized European air transport market, airport and airline companies are critically reevaluating their vertical governance structures. This paper analyzes the comparative efficiency of vertical governance structures in the airport-airline supply relationship. Using transaction cost economics as the lens of ...