GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2015-12-10
    Description: Different kinds of counterions (such as NO 3 – , ClO 4 – , and Cl – ) play a special role in controlling the framework of coordination compounds. Using this strategy, 5-aminotetrazole-1-propionic acid (Hatzp) was selected to react with praseodymium(III) nitrate or perchlorate in the same solvent system, producing two different coordination compounds, [Pr 2 (atzp) 4 (H 2 O) 8 ] · 2NO 3 · 2H 2 O ( 1 ) and [Pr 2 (atzp) 6 (H 2 O) 2 ] · H 2 O ( 2 ). These compounds were structurally characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. X-ray diffraction analysis revealed that compound 1 displays a dinuclear structure, whereas 2 shows a one dimensional zigzag chain framework. Furthermore, the luminescence properties of compounds 1 and 2 were investigated at room temperature in the solid state.
    Print ISSN: 0044-2313
    Electronic ISSN: 1521-3749
    Topics: Chemistry and Pharmacology
    Published by Wiley-Blackwell
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2014-03-14
    Description: ABSTRACT The wing of a dragonfly is thin and light, but can bear high frequent alternating stress and present excellent antifatigue properties. The surface morphology and microstructure of the wings of dragonfly Pantala flavescens were observed using SEM in this study. Based on the biological analysis method, the configuration, morphology, and structure of the vein were studied, and the antifatigue properties of the wings were investigated. The analytical results indicated that the longitudinal veins, cross veins, and membrane of dragonfly wing form a optimized network morphology and spacially truss-like structure which can restrain the formation and propagation of the fatigue cracks. The veins with multilayer structure present high strength, flexibility, and toughness, which are beneficial to bear alternating load during the flight of dragonfly. Through tensile-tensile fatigue failure tests, the results were verified and indicate that the wings of dragonfly P. flavescens have excellent antifatigue properties which are the results of the biological coupling and synergistic effect of morphological and structural factors. Microsc. Res. Tech., 2014 . © 2014 Wiley Periodicals, Inc.
    Print ISSN: 1059-910X
    Electronic ISSN: 1097-0029
    Topics: Natural Sciences in General
    Published by Wiley-Blackwell
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2017-06-04
    Description: Purpose To assess the efficacy of diffusion kurtosis imaging (DKI) and to compare DKI-derived parameters with that of conventional diffusion-weighted imaging (DWI) for grading the inflammatory activity of Crohn's disease (CD). Materials and Methods In all, 38 patients with CD underwent 3T magnetic resonance enterography (MRE) with DKI (b values of 0–2000 s/mm 2 ). The inflammatory activity of the bowel segments was graded by magnetic resonance index of activity (MaRIA) as inactive (〈7), mild (≥7 and 〈11), or moderate-severe (≥11). Apparent diffusion for non-Gaussian distribution (D app ) and apparent kurtosis coefficient (K app ) on DKI as well as apparent diffusion coefficient (ADC) on DWI were compared. Results In all, 86 bowel segments including inactive (20), mild (19), and moderate-severe (47) CD were analyzed. The differences in K app , D app , and ADC among inactive, mild, and moderate-severe CD were significant (all P 〈 0.05). K app ( r = 0.862), D app ( r = −0.755), and ADC ( r = −0.713) correlated well with MaRIA in all segments. Stronger correlation with MaRIA in moderate-severe CD was found for K app ( r = 0.647) than that of D app ( r = −0.414) and ADC ( r = −0.580). Receiver operating characteristic (ROC) curve analysis showed high accuracy of K app , D app , and ADC for differentiating active from inactive CD (AUC: 0.953 for K app , 0.944 for D app , 0.907 for ADC) as well as differentiating inactive-mild from moderate-severe CD (AUC: 0.946 for K app , 0.887 for D app , 0.846 for ADC). The threshold K app of 0.731 allowed differentiation of active from inactive CD with 89.4% sensitivity and 95% specificity. Conclusion DKI of CD is clinically feasible and might be superior to conventional DWI for grading the inflammatory activity of CD. Level of Evidence : 2 Technical Efficacy : Stage 2 J. Magn. Reson. Imaging 2017.
    Print ISSN: 1053-1807
    Electronic ISSN: 1522-2586
    Topics: Medicine
    Published by Wiley-Blackwell
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2015-06-16
    Description: Copper(II) coordination polymers have attracted considerable interest due to their catalytic, adsorption, luminescence and magnetic properties. The reactions of copper(II) with 2-amino-4-sulfobenzoic acid (H 2 asba) in the presence/absence of the auxiliary chelating ligand 1,10-phenanthroline (phen) under ambient conditions yielded two supramolecular coordination polymers, namely (3-amino-4-carboxybenzene-1-sulfonato-κ O 1 )bis(1,10-phenanthroline-κ 2 N , N ′)copper(II) 3-amino-4-carboxybenzene-1-sulfonate monohydrate, [Cu(C 7 H 6 N 2 O 5 S)(C 12 H 8 N 2 ) 2 ](C 7 H 6 N 2 O 5 S)·H 2 O, (1), and catena -poly[[diaquacopper(II)]-μ-3-amino-4-carboxylatobenzene-1-sulfonato-κ 2 O 4 : O 4′ ], [Cu(C 7 H 6 N 2 O 5 S)(H 2 O) 2 ] n , (2). The products were characterized by FT–IR spectroscopy, thermogravimetric analysis (TGA), solid-state UV–Vis spectroscopy and single-crystal X-ray diffraction analysis, as well as by variable-temperature powder X-ray diffraction analysis (VT-PXRD). Intermolecular π–π stacking interactions in (1) link the mononuclear copper(II) cation units into a supramolecular polymeric chain, which is further extended into a supramolecular double chain through interchain hydrogen bonds. Supramolecular double chains are then extended into a two-dimensional supramolecular double layer through hydrogen bonds between the lattice Hasba − anions, H 2 O molecules and double chains. Left- and right-handed 2 1 helices formed by the Hasba − anions are arranged alternately within the two-dimensional supramolecular double layers. Complex (2) exhibits a polymeric chain which is further extended into a three-dimensional supramolecular network through interchain hydrogen bonds. Complex (1) shows a reversible dehydration–rehydration behaviour, while complex (2) shows an irreversible dehydration–rehydration behaviour.
    Print ISSN: 0108-2701
    Electronic ISSN: 1600-5759
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2015-05-31
    Description: Vegetative filter strips (VFS) can effectively trap sediment in overland flow, but little information is available on its performance in controlling high-concentration sediment and the runoff hydraulics in VFS. Flume experiments were conducted to investigate the sediment deposition, hydraulics of overland flow and their relationships in simulating VFS under a great range of sediment concentrations with four levels of vegetation cover (bare slope and 4, 11 and 17%) and two flow rates (15 and 30 L min −1 ). Sediment concentrations varied from 30 to 400 kg m −3 and slope gradient was 9°. Both the deposited sediment load and deposition efficiency in VFS increased as the vegetation cover increased. Sediment concentration had a positive effect on the deposited load but no effect on deposition efficiency. A lower flow rate corresponded to greater deposition efficiency but had little effect on deposited load. Flow velocities decreased as vegetation cover increased. Sediment concentration had a negative effect on the mean velocity but no effect on surface velocity. Hydraulic resistance increased as the vegetation cover and sediment concentration increased. Sediment deposition efficiency had a much more pronounced relationship with overland flow hydraulics compared with deposited load, especially with the mean flow velocity, and there was a power relationship between them. Flow regime also affected the sediment deposition efficiency, and the efficiency was much higher under subcritical than supercritical flow. The results will be useful for the design of VFS and the control of sediment flowing into rivers in areas with serious soil erosion.
    Print ISSN: 0885-6087
    Electronic ISSN: 1099-1085
    Topics: Architecture, Civil Engineering, Surveying , Geography
    Published by Wiley-Blackwell
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2015-08-08
    Description: Two new coordination polymers (CPs) formed from 5-iodobenzene-1,3-dicarboxylic acid (H 2 iip) in the presence of the flexible 1,4-bis(1 H -imidazol-1-yl)butane (bimb) auxiliary ligand, namely poly[[μ 2 -1,4-bis(1 H -imidazol-1-yl)butane-κ 2 N 3 : N 3′ ](μ 3 -5-iodobenzene-1,3-dicarboxylato-κ 4 O 1 , O 1′ : O 3 : O 3′ )cobalt(II)], [Co(C 8 H 3 IO 4 )(C 10 H 14 N 4 )] n or [Co(iip)(bimb)] n , (1), and poly[[[μ 2 -1,4-bis(1 H -imidazol-1-yl)butane-κ 2 N 3 : N 3′ ](μ 2 -5-iodobenzene-1,3-dicarboxylato-κ 2 O 1 : O 3 )zinc(II)] trihydrate], {[Zn(C 8 H 3 IO 4 )(C 10 H 14 N 4 )]·3H 2 O} n or {[Zn(iip)(bimb)]·3H 2 O} n , (2), were synthesized and characterized by FT–IR spectroscopy, thermogravimetric analysis (TGA), solid-state UV–Vis spectroscopy, single-crystal X-ray diffraction analysis and powder X-ray diffraction analysis (PXRD). The iip 2− ligand in (1) adopts the (κ 1 ,κ 1 -μ 2 )(κ 1 , κ 1 -μ 1 )-μ 3 coordination mode, linking adjacent secondary building units into a ladder-like chain. These chains are further connected by the flexible bimb ligand in a trans – trans – trans conformation. As a result, a twofold three-dimensional interpenetrating α-Po network is formed. Complex (2) exhibits a two-dimensional (4,4) topological network architecture in which the iip 2− ligand shows the (κ 1 )(κ 1 )-μ 2 coordination mode. The solid-state UV–Vis spectra of (1) and (2) were investigated, together with the fluorescence properties of (2) in the solid state.
    Print ISSN: 0108-2701
    Electronic ISSN: 1600-5759
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2016-10-18
    Description: The Nd III coordination compounds [Nd(4-pytza) 3 (H 2 O) 2 ] · 2H 2 O ( 1 ) and [Nd(4-pytza) 2 (H 2 O) 4 ]Cl · 2H 2 O ( 2 ) [H4-pytza = 5-(4-pyridyl)tetrazole-2-acetic acid] were synthesized by reactions of K4-pytza and NdCl 3 · 6H 2 O at different pH values. Single crystal X-ray diffraction analysis reveals that 4-pytza ligands in 1 in a μ 1,3 -COO syn - syn or μ 1,1,3 -COO bridging mode coordinate to two central Nd III atoms to display a dinuclear unit, which is connected by one of these 4-pytza ligands acting in end-to-end bridging mode to form a 1D ladder-like chain. Different from 1 , each 4-pytza in 2 with a μ 1,3 -COO syn - anti bridging mode coordinates to two Nd III atoms to display a 1D zigzag chain. Furthermore, the luminescence properties of 1 and 2 were investigated at room temperature in the solid state.
    Print ISSN: 0044-2313
    Electronic ISSN: 1521-3749
    Topics: Chemistry and Pharmacology
    Published by Wiley-Blackwell
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...