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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.
- ItemMechanisms of bonding effected by nanoparticles in zirconia coatings applied by spraying of suspensions(Saarbrücke : Leibniz-Institut für Neue Materialien, 2008) Adam, Jens; Aslan, Mesut; Drumm, Robert; Veith, MichaelZirconia coatings consisting of a mixture of coarse and fine grained zirconia powders prepared by spraying of suspensions and subsequent thermal treatment at limited temperatures (up to 500°C) are poor in adherence and in intrinsic mechanical strength. We have shown elsewhere that mechanical properties of these coatings can be improved clearly by adding a small amount of nanoscaled zirconia. Here, the structural and the chemical development of this coating material and of the nanoparticles is examined to gain information about the underlying bonding mechanisms. The applied temperature is relatively low in comparison to the usual onset temperature of accelerated sintering. Nevertheless, the results show that diffusion controlled material transport mechanisms play their role in bonding. The condensation of surface OH groups may participate in bonding, too. These first results confirm the potential of nanoparticles to act as inorganic binder. Additional research effort to clarify the underlying mechanisms in detail is of interest. For the practical side, it can be concluded that the resulting effect of mechanical consolidation of ceramic structures at relatively low temperatures enables new ceramic applications, for example a new type of ceramic coatings on metallic substrates.
- ItemDevelopment of a mineral-specific sorption database for surface complexation modeling : part I: final report ; part II: Manual: RES 3 T: Rossendorf expert system for surface and sorption thermodynamics = Entwicklung einer mineralspezifischen Sorptions-Datenbank für Oberflächenkomplexierungsmodelle(Hannover : Technische Informationsbibliothek (TIB), 2004) Brendler, Vinzenz; Richter, Anke[no abstract available]
- ItemNew electronic device for driving surface acoustic wave actuators(Amsterdam : Elsevier, 2009) Brünig, R.; Mensel, K.; Kunze, R.; Schmidt, H.Surface acoustic wave (SAW) actuators are driven by a high frequency signal. The frequency range for an ideal SAW-generation is usually very narrow banded and may shift depending on various environmental conditions. We present a new electronic device which self-aligns to the optimal excitation frequency within a wide range. Any kind of SAW-actuator can be used. The device continuously scans a certain frequency range and characterizes the SAW-component. The ideal excitation frequency is then determined and used to drive the SAW-device. In case of changes like loading conditions or temperature variations the device automatically readjusts to the optimal frequency and prevents possible damage of the device or actuator in case of an error. © 2009.
- ItemLeuchtturmprojekt "Nachhaltige Aromatenchemie", Teilprojekt: Entwicklung von metallorganischen Katalysatoren für atomeffiziente Direktcarbonylierungen an Aromaten und Heteroaromaten : Abschlussbericht ; Laufzeit des Vorhabens/Berichtszeitraum: 01.04.2002 bis 31.03.2005(Hannover : Technische Informationsbibliothek (TIB), 2005) Beller, Matthias; Mertins, Kristin[no abstract available]
- ItemNuevo sistema integrado cromatografía líquida de alta resolución / nebulizador hidráulico de alta presión y temperatura (HPLC/HT-HHPN) para la separación automática de la matriz en la determinación de metales en salmueras con espectrometría de absorción atómica (FAAS)(Sao Paulo : Scielo, 2000) Yáñez, J.; Berndt, H.An integrated HPF-system using HPLC and HT-HHP-nebulizer is used for matrix separation by the determination of heavy metals in highly concentrated solutions with FAAS. The separation of the matrix (NaCl) is achieved in a HPLC RP-C18 column after heavy metal complexing with trans-1,2-diaminciclohexane-N,N,N ,N -tetraacetic acid (CDTA). Matrix separation and the metal determination can be realized in less than one minute, without any interference from the matrix. The detection limits of Cd(II), Co(II), Cr(VI), Cu(II), Mn(II) and Zn(II) by FAAS were improved in one order of magnitude in compare with the direct determination by pneumatic nebulization nebulizer.
- ItemChemie der schwersten Elemente: Hochtemperaturgaschromatographische Trennung und Erforschung kernchemischer Eigenschaften der Elemente 106 und 107, Seaborgium und Bohrium : Berichtszeitraum: 01.04.1997 bis 31.03.2000(Hannover : Technische Informationsbibliothek (TIB), 2000) Hübener, S.[no abstract available]
- ItemWork on non photocatalytically active titania particles(Saarbrücke : Leibniz-Institut für Neue Materialien, 2009) Müller, Thomas S.; Faller-Schneider, Christine; Moh, Karsten; Shanmugasundaram, Sakthivel; Oliveira, Peter W. de; Veith, MichaelTitanium dioxide has photocatalytic properties, i.e. under UV irradiation it develops an oxidative potential. In photocatalysis this is very desirable, but not when nano particulate titania is embedded into organic polymer matrices in order to increase the refractive index. UV irradiation would in this case destroy the material in the long run. For deactivation in general the titania is coated by e.g. silica or alumina which leads to other undesired effects like growth of the particle size and enhanced light scattering. The current work focuses on the application of techniques for doping during synthesis of crystallization of nano particulate TiO2. The photocatalysis activity was determined by degradation experiments of 4-chlorophenol using dip coated glass plates under artificial sunlight, where decreases of the photocatalytic effect of up to 90 % were found.
- ItemCrystal structure of rac-[1, 2-ethylene-bis(η5-4, 5, 6, 7-tetrahydroindenyl)]1-hafna-4, 5-bis(trimethylsilyl)furan-3-one- tris(pentafluorophenyl)borane, (C20H24)Hf(Me 3SiC2SiMe3CO2)B(C6F 5)3(Berlin : de Gruyter, 2009) Beweries, T.; Burlakov, V.V.; Rosenthal, U.; Spannenberg, A.C47H42BF15HfO2Si2, monoclinic, P121/n1 (no. 14), a = 15.7496(4) Å = 20.4074(5) Å= 16.3115(5) Å, β = 96.313(2)°, V= 5210.9 Å3, Z = 4, Rgt(F) = 0.027, WRref(F 2) = 0.049, T= 200 K. © by Oldenbourg Wissenschaftsverlag.
- ItemCrystal structure of (η4-cycloocta-1,5-dien)-N-(2- (diphenylphosphinooxy)-3-(naphthalen-1-yloxy)propyl)-N-(pentan-3-yl)-1, 1-diphenylphosphinamine-rhodium(I) tetrafluoroborate, [Rh(C8H 12)(C42H43NO2P2)][BF 4](Berlin : de Gruyter, 2007) Dai, Z.; Heller, D.; Preetz, A.; Drexler, H.-J.C50H55BF4NO2P2Rh, monoclinic, P1211 (no. 4), a = 12.722(3) Å, b = 15.248(3) Å, c = 12.818(3) Å, β = 115.80(3)°, V = 2238.7 Å3, Z = 2, Rgt(F) = 0.036, wRref(F 2) = 0.079, T = 200 K. © by Oldenbourg Wissenschaftsverlag.