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- ItemDicyclohexylbis(naphthalen-1-ylmethyl)phosphonium chloride chloroform disolvate(Chester : International Union of Crystallography, 2012) Gowrisankar, S.; Neumann, H.; Spannenberg, A.; Beller, M.In the title solvated phosphonium salt, C34H40P+·Cl -·2CHCl3, the two cyclohexyl and two 1-naphthylmethyl groups at the P atom are in a distorted tetrahedral arrangement [105.26 (6)-113.35 (6)°]. Both cyclohexyl rings adopt a chair conformation. The dihedral angle between the naphthyl ring systems is 74.08 (3)°.
- ItemDicarbonyl-{3,3′-di-tert-butyl-5,5′-di-methoxy-2, 2′-bis[(4,4,5,5-tetraphenyl-1,3,2-dioxaphospho-lan-2-yl)-oxy-κP] biphen-yl}hydridorhodium(I) diethyl ether monosolvate(Chester : International Union of Crystallography, 2012) Selent, D.; Spannenberg, A.; Börner, A.In the title compound, [Rh(C 74H 68O 8P2)H(CO) 2]·C 4H 10O, the C 2HP 2 coordination set at the Rh I ion is arranged in a distorted trigonal-planar geometry with one P atom of the diphosphite mol-ecule and the H atom adopting the axial coordination sites.
- Item2,4-Bis(diphenyl-phosphan-yl)-1,1,2,3,3,4-hexa-phenyl-1,3-diphospha-2, 4-dibora-cyclo-butane tetra-hydro-furan sesqui-solvate(Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.In the title compound, C60H50B2P 4·1.5C4H8O, the diphospha-diborane mol-ecule lies on an inversion centre, whereas the disordered tetra-hydro-furan solvent mol-ecule is in a general position with a partial occupancy of 0.75. The diphosphadiborane mol-ecule consists of an ideal planar four-membered B 2P2 ring with an additional phenyl and a-PPH2 group attached to each B atom.
- ItemDi-μ-sulfido-bis{[rac-1,2-bis(η5-4,5,6, 7-tetrahydroinden-1-yl)ethane]zirconium(IV)} toluene monosolvate(Chester : International Union of Crystallography, 2012) Haehnel, M.; Altenburger, K.; Spannenberg, A.; Arndt, P.; Rosenthal, U.The title dimeric zirconium complex, [Zr3(C20H 24)2S2]·C7H8, was obtained from the reaction of (ebthi)Zr(η2-Me3Si-C2-SiMe3) [ebthi is rac-1,2-bis(η5-4,5,6,7-tetrahydroinden-1-yl)ethane] and S=C=N-ada (ada = adamantan-1-yl) along with the formation of the isonitrile C N-ada. Each ZrIV atom is coordinated by the sterically hindered ebthi ligand and two μ-sulfide ligands in a strongly distorted tetrahedral geometry. The [ZrS]2 unit is almost planar (mean deviation from the best plane of the four atoms = 0.025Å). A -CH2-CH2- group in one ebthi ligand was disordered over two sites, with refined occupancy factors of 0.551(6) and 0.449(6). The asymmetric unit also contains a toluene solvent molecule.
- ItemTetracarbonyl[bis(diphenylphosphanyl)-tetramethyldisiloxane- κ 2 P,P′]chromium(0)(Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C 28H 32OP 2Si 2)(CO) 4], was obtained by the ligand-exchange reaction of Cr(CO) 6 with (Ph 2PSiMe 2) 2O in refluxing toluene. The CrC 4P 2 coordination geometry is distorted octa-hedral, with a P - Cr - P bite angle of 99.22 (4)°.
- ItemThe influence of Mg doping on the nucleation of self-induced GaN nanowires(New York : American Institute of Physics, 2012) Limbach, F.; Caterino, R.; Gotschke, T.; Stoica, T.; Calarco, R.; Geelhaar, L.; Riechert, H.GaN nanowires were grown without any catalyst by plasma-assisted molecular beam epitaxy. Under supply of Mg, nanowire nucleation is faster, the areal density of wires increases to a higher value, and nanowire coalescence is more pronounced than without Mg. During nanowire nucleation the Ga desorption was monitored insitu by line-of-sight quadrupolemass spectrometry for various substrate temperatures. Nucleation energies of 4.0±0.3 eV and 3.2±0.3 eV without and with Mg supply were deduced, respectively. This effect has to be taken into account for the fabrication of nanowire devices and could be employed to tune the NW areal density.
- ItemPronounced ductility in CuZrAl ternary bulk metallic glass composites with optimized microstructure through melt adjustment(New York : American Institute of Physics, 2012) Liu, Zengqian; Li, Ran; Liu, Gang; Song, Kaikai; Pauly, Simon; Zhang, Tao; Eckert, JürgenMicrostructures and mechanical properties of as-cast Cu47.5Zr47.5Al5 bulk metallic glass composites are optimized by appropriate remelting treatment of master alloys. With increasing remelting time, the alloys exhibit homogenized size and distribution of in situ formed B2 CuZr crystals. Pronounced tensile ductility of ∼13.6% and work-hardening ability are obtained for the composite with optimized microstructure. The effect of remelting treatment is attributed to the suppressed heterogeneous nucleation and growth of the crystalline phase from undercooled liquid, which may originate from the dissolution of oxides and nitrides as well as from the micro-scale homogenization of the melt.
- ItemMAARSY-the new MST radar on Andøya: First results of spaced antenna and Doppler measurements of atmospheric winds in the troposphere and mesosphere using a partial array(Göttingen : Copernicus, 2012) Stober, G.; Latteck, R.; Rapp, M.; Singer, W.; Zecha, M.MST radars have been used to study the troposphere, stratosphere and mesosphere over decades. These radars have proven to be a valuable tool to investigate atmospheric dynamics. MAARSY, the new MST radar at the island of Andøya uses a phased array antenna and is able to perform spaced antenna and Doppler measurements at the same time with high temporal and spatial resolution. Here we present first wind observations using the initial expansion stage during summer 2010. The tropospheric spaced antenna and Doppler beam swinging experiments are compared to radiosonde measurements, which were launched at the nearby Andøya Rocket Range (ARR). The mesospheric wind observations are evaluated versus common volume meteor radar wind measurements. The beam steering capabilities of MAARSY are demonstrated by performing systematic scans of polar mesospheric summer echoes (PMSE) using 25 and 91 beam directions. These wind observations permit to evaluate the new radar against independent measurements from radiosondes and meteor radar measurements to demonstrate its capabilities to provide reliable wind data from the troposphere up to the mesosphere.
- Item(+)-Chlorido[(1,2,3,4-η;P 2′)-2′- diphenylphosphanyl-2-diphenylphosphoryl-1,1′-binaphthyl]rhodium(I) methanol monosolvate(Chester : International Union of Crystallography, 2012) Meissner, A.; Selle, C.; Drexler, H.-J.; Heller, D.In the title complex, [RhCl(C 44H 32OP 2)]·CH 3OH, the Rh I ion is coordinated by a naphthyl group of a partially oxidized 2,2′-bis-(diphenylphosphanyl)-1, 1′-binaphthyl (BINAP) ligand in a 4 mode, one P atom of the diphenylphosphanyl group and one Cl atom. The P=O group does not interact with the Rh I ion but accepts an O - H⋯O hydrogen bond from the methanol solvent molecule.
- ItemPotential climate change impacts on the water balance of subcatchments of the River Spree, Germany(München : European Geopyhsical Union, 2012) Pohle, I.; Koch, H.; Grünewald, U.Lusatia is considered one of the driest regions of Germany. The climatic water balance is negative even under current climate conditions. Due to global climate change, increased temperatures and a shift of precipitation from summer to winter are expected. Therefore, it is of major interest whether the excess water in winter can be stored and to which extent it is used up on increasing evapotranspiration. Thus, this study focuses on estimating potential climate change impacts on the water balance of two subcatchments of the River Spree using the Soil and Water Integrated Model (SWIM). Climate input was taken from 100 realisations each of two scenarios of the STatistical Analogue Resampling scheme STAR assuming a further temperature increase of 0 K (scenario A) and 2 K by the year 2055 (scenario B) respectively. Resulting from increased temperatures and a shift in precipitation from summer to winter actual evapotranspiration is supposed to increase in winter and early spring, but to decrease in later spring and early summer. This is less pronounced for scenario A than for scenario B. Consequently, also the decrease in discharge and groundwater recharge in late spring is lower for scenario A than for scenario B. The highest differences of runoff generation and groundwater recharge between the two scenarios but also the highest ranges within the scenarios occur in summer and early autumn. It is planned to estimate potential climate change for the catchments of Spree, Schwarze Elster and Lusatian Neisse.