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    Iodidobis(≠5-penta-methyl-cyclo-penta-dien-yl)titanium(III)
    (Chester : International Union of Crystallography, 2010) Kessler, M.; Spannenberg, A.; Rosenthal, U.
    In the title complex mol-ecule, [Ti(C10H15) 2I], the paramagnetic Ti(III) atom is coordinated by two penta-methyl-cyclo-penta-dienyl (Cp*) ligands and one iodide ligand. The two Cp*ligands are in a staggered orientation. The coordination geometry at the titanium atom can be described as distorted trigonal-planar.
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    Tris(η5-cyclopentadienyl)hafnium(III)
    (Chester : International Union of Crystallography, 2011) Burlakov, V.V.; Arndt, P.; Spannenberg, A.; Rosenthal, U.
    In the crystal structure of the title compound, [Hf(C5H 5)3], three cyclopentadienyl ligands surround the Hf III atom in a trigonal-planar geometry. The molecule lies on a sixfold inversion axis.
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    Ethyl 4-chloro-2′-fluoro-3-hydroxy-5-methylbiphenyl-2-carboxylate
    (Chester : International Union of Crystallography, 2011) Adeel, M.; Langer, P.; Villinger, A.
    In the title compound, C 16H 14ClFO 3, the dihedral angle between the mean planes of the two benzene rings is 71.50 (5)°. Due to an intramolecular O - H⋯O hydrogen bond between the hydroxy group and the carbonyl O atom of the ethyl ester group, the ethyl ester group lies within the ring plane. The crystal structure is consolidated by intermolecular C - H⋯O and C - H⋯F interactions.
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    [2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate
    (Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, [Cr(C27H26P2)(CO) 4]·CH2Cl2, was obtained by the reaction of Ph2PCMe2PPh2 with Cr(CO)6 in refluxing toluene by substitution of two carbonyl ligands. The CrC 4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 70.27 (2)°.
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    (Isopropyl-amino)(meth-yl)diphenyl-phospho-nium iodide
    (Chester : International Union of Crystallography, 2011) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, C 16H 21NP +· I -, was obtained by the reaction of PH 2PN( iPr)P(Ph)N( iPr)H with MeI involving cleavage of one of the P - N bonds in diethyl ether. The two phenyl rings form a dihedral angle of 82.98 (5)°. A weak donor-acceptor N - H⋯I inter-action is observed.
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    Water footprint analysis for the assessment of milk production in Brandenburg (Germany)
    (München : European Geopyhsical Union, 2010) Drastig, K.; Prochnow, A.; Kraatz, S.; Klauss, H.; Plöchl, M.
    The working group "Adaptation to Climate Change" at the Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB) is introduced. This group calculates the water footprint for agricultural processes and farms, distinguished into green water footprint, blue water footprint, and dilution water footprint. The green and blue water demand of a dairy farm plays a pivotal role in the regional water balance. Considering already existing and forthcoming climate change effects there is a need to determine the water cycle in the field and in housing for process chain optimisation for the adaptation to an expected increasing water scarcity. Resulting investments to boost water productivity and to improve water use efficiency in milk production are two pathways to adapt to climate change effects. In this paper the calculation of blue water demand for dairy farming in Brandenburg (Germany) is presented. The water used for feeding, milk processing, and servicing of cows over the time period of ten years was assessed in our study. The preliminary results of the calculation of the direct blue water footprint shows a decreasing water demand in the dairy production from the year 1999 with 5.98×109 L/yr to a water demand of 5.00×109 L/yr in the year 2008 in Brandenburg because of decreasing animal numbers and an improved average milk yield per cow. Improved feeding practices and shifted breeding to greater-volume producing Holstein-Friesian cow allow the production of milk in a more water sustainable way. The mean blue water consumption for the production of 1 kg milk in the time period between 1999 to 2008 was 3.94±0.29 L. The main part of the consumed water seems to stem from indirect used green water for the production of feed for the cows.
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    The STELLA robotic observatory on tenerife
    (New York : Hindawi Publishing Corporation, 2010) Strassmeier, K.G.; Granzer, T.; Weber, M.; Woche, M.; Popow, E.; Jrvinen, A.; Bartus, J.; Bauer, S.-M.; Dionies, F.; Fechner, T.; Bittner, W.; Paschke, J.
    The Astrophysical Institute Potsdam (AIP) and the Instituto de Astrofísica de Canarias (IAC) inaugurated the robotic telescopes STELLA-I and STELLA-II (STELLar Activity) on Tenerife on May 18, 2006. The observatory is located on the Izaa ridge at an elevation of 2400m near the German Vacuum Tower Telescope. STELLA consists of two 1.2m alt-az telescopes. One telescope fiber feeds a bench-mounted high-resolution echelle spectrograph while the other telescope feeds a wide-field imaging photometer. Both scopes work autonomously by means of artificial intelligence. Not only that the telescopes are automated, but the entire observatory operates like a robot, and does not require any human presence on site. Copyright © 2010 Klaus G. Strassmeier et al.
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    Climatology of northern polar latitude MLT dynamics: Mean winds and tides
    (Göttingen : Copernicus, 2010) Kumar, G.K.; Hocking, W.K.
    Mean winds and tides in the northern polar Mesosphere and Lower Thermosphere (MLT) have been studied using meteor radars located at Resolute Bay (75° N, 95° W) and Yellowknife (62.5° N, 114.3° W). The measurements for Resolute Bay span almost 12 years from July 1997 to February 2009 and the Yellowknife data cover 7 years from June 2002 to October 2008. The analysis reveals similar wind flow over both sites with a difference in magnitude. The summer zonal flow is westward at lower heights, eastward at upper heights and the winter zonal flow is eastward at all heights. The winter meridional flow is poleward and sometimes weakly equatorward, while non winter months show equatorward flow, with a strong equatorward jet during mid-summer months. The zonal and meridional winds show strong interannual variation with a dominant annual variation as well as significant latitudinal variation. Year to year variability in both zonal and meridional winds exists, with a possible solar cycle dependence. The diurnal, semidiurnal and terdiurnal tides also show large interannual variability and latitudinal variation. The diurnal amplitudes are dominated by an annual variation. The climatological monthly mean winds are compared with CIRA 86, GEWM and HWM07 and the climatological monthly mean amplitudes and phases of diurnal and semidiurnal tides are compared with GSWM00 predictions. The GEWM shows better agreement with observations than the CIRA 86 and HWM07. The GSWM00 model predictions need to be modified above 90 km. The agreements and disagreements between observations and models are discussed. © 2010 Author(s).
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    Three years of experience with the STELLA robotic observatory
    (New York : Hindawi Publishing Corporation, 2010) Granzer, T.; Weber, M.; Strassmeier, K.G.
    Since May 2006, the two STELLA robotic telescopes at the Izaa observatory in Tenerife, Spain, delivered an almost uninterrupted stream of scientific data. To achieve such a high level of autonomous operation, the replacement of all troubleshooting skills of a regular observer in software was required. Care must be taken on error handling issues and on robustness of the algorithms used. In the current paper, we summarize the approaches we followed in the STELLA observatory. Copyright © 2010 Thomas Granzer et al.