@article{39757, abstract = {{It is well known that robust and reliable photonic crystal structures can be manufactured with very high precision by electrochemical etching of silicon wafers, which results in two- and three-dimensional photonic crystals made of macroporous silicon. However, tuning of the photonic properties is necessary in order to apply these promising structures in integrated optical devices. For this purpose, different effects have been studied, such as the infiltration with addressable dielectric liquids (liquid crystals), the utilization of Kerr-like nonlinearities of the silicon, or free-charge carrier injection by means of linear (one-photon) and nonlinear (two-photon) absorptions. The present article provides a review, critical discussion, and perspectives about state-of-the-art tuning capabilities.}}, author = {{Kitzerow, Heinz-Siegfried and Matthias, Heinrich and Schweizer, Stefan L. and van Driel, Henry M. and Wehrspohn, Ralf B.}}, issn = {{1687-6393}}, journal = {{Advances in Optical Technologies}}, publisher = {{Hindawi}}, title = {{{Tuning of the Optical Properties in Photonic Crystals Made of Macroporous Silicon}}}, volume = {{2008}}, year = {{2008}}, } @article{41276, author = {{Graziola, Francesco and Girardi, Fabrizio and Bauer, Matthias and Di Maggio, Rosa and Rovezzi, Mauro and Bertagnolli, Helmut and Sada, Cinzia and Rossetto, Gilberto and Gross, Silvia}}, issn = {{0032-3861}}, journal = {{Polymer}}, keywords = {{Polymers and Plastics, Materials Chemistry, Organic Chemistry}}, number = {{20}}, pages = {{4332--4343}}, publisher = {{Elsevier BV}}, title = {{{UV-photopolymerisation of poly(methyl methacrylate)-based inorganic–organic hybrid coatings and bulk samples reinforced with methacrylate-modified zirconium oxocluster}}}, doi = {{10.1016/j.polymer.2008.08.005}}, volume = {{49}}, year = {{2008}}, } @book{40012, author = {{Blumberg, Eva}}, title = {{{Multikriteriale Zielerreichung im naturwissenschaftsbezogenen Sachunterricht der Grundschule – Eine Studie zum Einfluss von Strukturierung in schülerorientierten Lehr-Lernumgebungen auf das Erreichen kognitiver, motivationaler und selbstbezogener Zielsetzungen. Inaugural-Dissertation zur Erlangung des akademischen Grades des Doktors in den Erziehungswissenschaften an der Westfälischen Wilhelms-Universität Münster}}}, year = {{2008}}, } @article{41277, author = {{Rill, Christoph and Bauer, Matthias and Bertagnolli, Helmut and Kickelbick, Guido}}, issn = {{0021-9797}}, journal = {{Journal of Colloid and Interface Science}}, keywords = {{Colloid and Surface Chemistry, Surfaces, Coatings and Films, Biomaterials, Electronic, Optical and Magnetic Materials}}, number = {{1}}, pages = {{179--186}}, publisher = {{Elsevier BV}}, title = {{{Microemulsion approach to neodymium, europium, and ytterbium oxide/hydroxide colloids—Effects of precursors and preparation parameters on particle size and crystallinity}}}, doi = {{10.1016/j.jcis.2008.05.008}}, volume = {{325}}, year = {{2008}}, } @article{41278, author = {{Akdogan, Yasar and Vogt, Christina and Bauer, Matthias and Bertagnolli, Helmut and Giurgiu, Liviu and Roduner, Emil}}, issn = {{1463-9076}}, journal = {{Physical Chemistry Chemical Physics}}, keywords = {{Physical and Theoretical Chemistry, General Physics and Astronomy}}, number = {{20}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Platinum species in the pores of NaX, NaY and NaA zeolites studied using EPR, XAS and FTIR spectroscopies}}}, doi = {{10.1039/b718932j}}, volume = {{10}}, year = {{2008}}, } @article{41279, author = {{Wu, Jin-Ming and Antonietti, Markus and Gross, Silvia and Bauer, Matthias and Smarsly, Bernd M.}}, issn = {{1439-4235}}, journal = {{ChemPhysChem}}, keywords = {{Physical and Theoretical Chemistry, Atomic and Molecular Physics, and Optics}}, number = {{5}}, pages = {{748--757}}, publisher = {{Wiley}}, title = {{{Ordered Mesoporous Thin Films of Rutile TiO2 Nanocrystals Mixed with Amorphous Ta2O5}}}, doi = {{10.1002/cphc.200700679}}, volume = {{9}}, year = {{2008}}, } @article{31720, author = {{Reinsberger, Claus and Dorn, T and Krämer, G}}, issn = {{1059-1311}}, journal = {{Seizure}}, number = {{7}}, pages = {{651--653}}, title = {{{Smoking reduces serum levels of lamotrigine.}}}, volume = {{17}}, year = {{2008}}, } @article{31749, author = {{Gentner, R and Wankerl, K and Reinsberger, Claus and Zeller, D and Classen, J}}, issn = {{1047-3211}}, journal = {{Cereb Cortex}}, number = {{9}}, pages = {{2046--2053}}, title = {{{Depression of human corticospinal excitability induced by magnetic theta-burst stimulation: evidence of rapid polarity-reversing metaplasticity.}}}, volume = {{18}}, year = {{2008}}, } @article{41999, author = {{Liu, Jianing and Rieger, Jens and Huber, Klaus}}, issn = {{0743-7463}}, journal = {{Langmuir}}, keywords = {{Electrochemistry, Spectroscopy, Surfaces and Interfaces, Condensed Matter Physics, General Materials Science}}, number = {{15}}, pages = {{8262--8271}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Analysis of the Nucleation and Growth of Amorphous CaCO3 by Means of Time-Resolved Static Light Scattering}}}, doi = {{10.1021/la8006519}}, volume = {{24}}, year = {{2008}}, } @inproceedings{44112, abstract = {{Homogeneous and inhomogeneous broadening of heavy- and light-hole excitons in semiconductor quantum wells are measured along with the excitation dependence of both broadenings. Isolation of disorder-induced broadening is possible with spectra in different coherent pathways.}}, author = {{Meier, Torsten and Zhang, Tianhao and Bristow, Alan D. and Dai, Xingcan and Kuznetsova, Irina and Thomas, P. and Cundiff, S.T.}}, booktitle = {{Quantum Electronics and Laser Science Conference}}, isbn = {{978-1-55752-859-9}}, location = {{San Jose, California United States}}, publisher = {{Optical Society of America}}, title = {{{Direct determination of exciton homogeneous and inhomogeneous linewidths in semiconductor quantum wells with two-dimensional fourier transform spectroscopy}}}, year = {{2008}}, } @inproceedings{44110, author = {{Meier, Torsten and Duc, Huynh Thanh and Koch, S.W. and Pasenow, B.}}, booktitle = {{72nd annual meeting and DPG spring meeting of the Condensed Matter Section and the Divisions}}, location = {{Berlin, Germany}}, title = {{{Intensity dependence of charge and spin currents generated by ultrafast two-color photoexcitation of semiconductor quantum wells}}}, volume = {{43}}, year = {{2008}}, } @inproceedings{44111, author = {{Meier, Torsten and Koch, S.W. and Pasenow, B.}}, booktitle = {{72nd annual meeting and DPG spring meeting of the Condensed Matter Section and the Divisions}}, location = {{Berlin, Germany}}, title = {{{Influence of heavy-hole light-hole band mixing on the strength of optically generated spin-currents in III-V semiconductor quantum wells}}}, volume = {{42}}, year = {{2008}}, } @article{23483, abstract = {{The emitted radiation from semiconductor nanostructures due to the excitation with intense ultrashort optical laser pulses is analyzed. Semiconductor Bloch equations that consistently describe the coupled light-field-induced interband and intraband dynamics are solved numerically. It is demonstrated that the intraband dynamics considerably influences the light emission in the regime of extreme nonlinear optics. In particular, the intraband acceleration significantly modifies the dynamics of the interband polarization which results in a strong enhancement of high-harmonic generation.}}, author = {{Golde, D. and Meier, Torsten and Koch, S. W.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{7}}, title = {{{High harmonics generated in semiconductor nanostructures by the coupled dynamics of optical inter- and intraband excitations}}}, doi = {{10.1103/physrevb.77.075330}}, volume = {{77}}, year = {{2008}}, } @inbook{44109, author = {{Meier, Torsten and Pasenow, B. and Reichelt, Matthias and Stroucken, T.}}, booktitle = {{Nanophotonic Materials: Photonic Crystals, Plasmonics, and Metamaterials}}, editor = {{Busch, Kurt and Kitzerow, H.-S. and Wehrspohn, Ralf B.}}, isbn = {{9783527408580 }}, pages = {{15--38}}, publisher = {{Wiley‐VCH Verlag GmbH & Co. KGaA}}, title = {{{Microscopic Analysis of the Optical and Electronic Properties of Semiconductor Photonic-Crystal Structures}}}, doi = {{10.1002/9783527621880.ch2}}, year = {{2008}}, } @article{25980, abstract = {{Mesoporous SBA-15 (space group p6mm), KIT-6 (Ia3d) and KIT-5 (Fm3m) silicas, exhibiting different 2-D and 3-D channel- or cage-like pore structure and pore dimensions have been used as supports for iron oxide nanoparticles. The iron modification of the silica was performed according to a frequently used impregnation technique from aqueous iron nitrate solution. The materials were characterized by nitrogen physisorption, X-ray diffraction, TEM–EDX, Moessbauer spectroscopy, and temperature-programmed reduction (TPR) and tested in the catalytic decomposition of methanol. It is established that the location and dispersion of iron oxide nanoparticles are affected by the pore topology of the support. The most homogeneously dispersed iron oxide nanoparticles are observed using silica host matrix exhibiting a 3-D channel-like structure and pore diameters about 7 nm, and the thus-obtained composites exhibit high catalytic activity and selectivity in methanol decomposition to CO and hydrogen. For all the samples, characterized with a low mesopore volume and small pore diameters/pore entrances, the formation of larger iron oxide particles, mainly located on the outer surface, is observed. Inhomogeneously dispersed iron oxide particles with a large fraction of isolated, strongly interacting with the support, iron species, and possessing low catalytic activity and usually high selectivity to methane, are found for the silicas with relatively larger pores/pore entrances.}}, author = {{Tsoncheva, Tanya and Rosenholm, Jessica and Linden, Mika and Kleitz, Freddy and Tiemann, Michael and Ivanova, Ljubomira and Dimitrov, Momtchil and Paneva, Daniela and Mitov, Ivan and Minchev, Christo}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{327--337}}, title = {{{Critical evaluation of the state of iron oxide nanoparticles on different mesoporous silicas prepared by an impregnation method}}}, doi = {{10.1016/j.micromeso.2007.10.005}}, year = {{2008}}, } @article{25979, abstract = {{Various measures to optimise the impregnation of mesoporous CMK-3 carbon and SBA-15 silica matrices with metal nitrates for the synthesis of mesoporous metal oxides by structure replication are investigated. The effect of surface modification of the matrix pores, the choice of a solvent with suitable polarity, and the concentration of the metal nitrate solution are studied in detail. The efficiency of pore loading is monitored by nitrogen physisorption measurements. The creation of polar functions at the pore surface of CMK-3 carbon is shown to increase the impregnation efficiency substantially while maximizing the pore wall polarity of SBA-15 silica by increasing the amount of free silanol groups does not have any significant impact. The choice of a less polar solvent (THF instead of water) has a positive effect on the wettability of CMK-3 carbon in the first impregnation cycle but turns out to be disadvantageous in the second cycle; a similar trend is observed for variation of the metal salt concentration.}}, author = {{Roggenbuck, Jan and Waitz, Thomas and Tiemann, Michael}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{575--582}}, title = {{{Synthesis of mesoporous metal oxides by structure replication: Strategies of impregnating porous matrices with metal salts}}}, doi = {{10.1016/j.micromeso.2007.12.018}}, year = {{2008}}, } @article{25982, abstract = {{Iron (III) containing nanoparticles with superparamagnetic behaviour are prepared via deposition on various mesoporous supports (MgO, CeO2 and SBA-15). XRD, TEM-EDX, N2 physisorption, FTIR, and Moessbauer spectroscopy are used for their characterization. The reductive properties and catalytic behaviour in methanol decomposition of the materials are also studied. Depending on the chemical nature of the support, the predominant formation of: isolated iron species, strongly interacting with the support (for SBA-15), mixture of hematite and binary MgFe2O4 nanoparticles (for MgO) or almost homogeneously dispersed hematite particles (for CeO2) are observed. The state of iron species strongly affects their catalytic properties. The favorable effect of the support mesoporosity on the catalytic activity is most pronounced for the iron modified CeO2.}}, author = {{Tsoncheva, Tanya and Roggenbuck, Jan and Tiemann, Michael and Ivanova, Lyubomira and Paneva, Daniela and Mitov, Ivan and Minchev, Christo}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{339--346}}, title = {{{Iron oxide nanoparticles supported on mesoporous MgO and CeO2: A comparative physicochemical and catalytic study}}}, doi = {{10.1016/j.micromeso.2007.06.021}}, year = {{2008}}, } @inbook{25983, abstract = {{Nanoporous semiconducting metal oxide materials (In2O3, WO3) with uniform pore systems, large specific surface areas (80 m2 g−1), and pore-wall crystallinity were prepared by structure replication, using KIT-6 silica as a template. The products show improved properties as gas sensors (for methane or butanone) as compared to non-porous samples. In addition, porous WO3 samples with comparable porosity (prepared by conventional ‘soft templating’, using pluronic P123), which are amorphous on the atomic length scale show poorer gas sensitivity, indicating that crystallinity is a crucial factor in the sensing process.}}, author = {{Waitz, Thomas and Wagner, Thorsten and Kohl, Claus-Dieter and Tiemann, Michael}}, booktitle = {{Zeolites and related materials: Trends, targets and challenges, Proceedings of the 4th International FEZA Conference}}, issn = {{0167-2991}}, title = {{{New mesoporous metal oxides as gas sensors}}}, doi = {{10.1016/s0167-2991(08)80227-3}}, year = {{2008}}, } @article{25981, abstract = {{The growth of ZnS nanoparticles during precipitation from aqueous solution is studied by in situ stopped-flow UV absorption spectroscopy at temperatures between 283 and 323 K. Particle growth is marked by substantial ripening during the first 60 ms. Kinetic data suggest that a ripening mechanism by coalescence (oriented attachment) is predominant over Ostwald ripening, although the latter seems to coexist to a significant degree at early temporal stages, predominantly at low temperatures.}}, author = {{Tiemann, Michael and Marlow, Frank and Hartikainen, Juha and Weiss, Özlem and Lindén, Mika}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, pages = {{1463--1467}}, title = {{{Ripening Effects in ZnS Nanoparticle Growth}}}, doi = {{10.1021/jp077729f}}, year = {{2008}}, } @article{25978, abstract = {{In recent years, a lot of research activity has focused on the synthesis of new ordered porous materials by utilization of porous matrices as templates. Since the matrices are themselves created by templating procedures, the entire process can be envisaged as “repeated templating”. This review describes recent conceptual developments in the field of structure replication and summarizes the large number of publications on new functional materials prepared by this method.}}, author = {{Tiemann, Michael}}, issn = {{0897-4756}}, journal = {{Chemistry of Materials}}, pages = {{961--971}}, title = {{{Repeated Templating}}}, doi = {{10.1021/cm702050s}}, year = {{2008}}, }