109 research outputs found

    Synthesis and application of zeolite and glass fiber supported zero valent iron nanoparticles as membrane component for removal nitrate and Cr (+6) ions

    Get PDF
    In the present paper the synthesis and characterization of zeolite and glass fiber supported zero valent iron nanoparticles (Ze-ZVI, GF-ZVI NPs) are reported.ZVI, Ze-ZVI and GF-ZVI NPs size, composition and morphology were characterized by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Energy Dispersive Spectroscopy (EDS). Synthesized nanostructures were tested as reducing agents of nitrate and hexavalent Chromium. Batch experiments were carried for revealing of efficacy of prepared nanomaterials (ZE-ZVI NPs and GF-ZVI NPs). Nitrate removal efficiency (at initial concentration 50 mg/mL) was rapidly increased from 26% to 76% for GF-ZVI NPs at 60-240 min time interval for and from 34% to 90% for ZE-ZVI NPs at the same time interval.Also was studied the efficacy of prepared nanostructures ZE-ZVI and ZE-ZVI NPs as membrane component with 5% of ZVI NPS weight contentfor the removal of nitrate from water solution that made 85% for ZE-ZVI NPs and 76% for GF-ZVI NPs, respectively. The results of this study indicate that the application of GF-ZVI and ZE-ZVI NPs as membrane component is advantageous because it allows to prevent the additional pollution of treated solution caused by unreacted ZVI NPs

    Role of structure of the Pp/magnetite nanocomposites on their thermal properties

    Get PDF
    The thermal degradation behaviour of polypropylene and its magnetite composites have been investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Distribution of magnetite nanoparticles in a polymer matrix has been studied by scanning and transmission electron microscopy and also atomic force microscopy. The thermal and mechanical properties of nanocomposites based on polypropylene and magnetite nanoparticles have also been investigated. It has shown that, the introduction of Fe3O4 nanoparticles in polypropylene increases its thermal stability of about 1000C. The maximum increase in the thermal stability of PP was observed in the case of a 20% weight content of Fe3O4 nanoparticles in polypropylene

    Regularizing velocity differences in time-lapse FWI using gradient mismatch information

    Get PDF
    We present a method for recovering time-lapse velocity changes using full waveform inversion (FWI). In a preprocessing step we invert for a single intermediate model by simultaneously minimizing the data misfit in the baseline and the monitor surveys. We record the individual FWI gradients corresponding to the baseline and the monitor datasets at each iteration of the inversion. Regions where these gradients consistently have opposing sign are likely to correspond to locations of time-lapse change. This insight is used to generate a spatially varying confidence map for time-lapse change. In a subsequent joint inversion we invert for baseline and monitor models while regularizing the difference between the models with this spatially varying confidence map. Unlike double difference full waveform inversion (DDFWI) we do not require identical source and receiver positions in the baseline and monitor surveys

    rac-(1R*,2S*,3S*)-Diethyl 4-methyl-2-phenyl-6-(2-phenyl­hydrazinyl­idene)cyclo­hex-4-ene-1,3-dicarboxyl­ate

    Get PDF
    In the title compound, C25H28N2O4, the cyclohexene ring adopts a half-chair conformation and the dihedral angle between the aromatic rings is 59.44 (11)°. In the crystal, a weak intermolecular N—H⋯O hydrogen bond occurs

    rac-1-(6-Hy­droxy-3,6-dimethyl-4-phenyl-4,5,6,7-tetra­hydro-2,1-benzoxazol-5-yl)ethanone

    Get PDF
    The structure of the title compound, C17H19NO3, is of inter­est with respect to anti­bacterial properties, anti­biotic properties and biological activity. The structure displays inter­molecular O—H⋯N hydrogen bonding

    Ethyl 3,6-dihy­droxy-6-methyl-4-phenyl-4,5,6,7-tetra­hydro-1H-indazole-5-carboxyl­ate monohydrate

    Get PDF
    In the title compound, C17H20N2O4·H2O, the cyclo­hexene ring adopts a half-chair conformation while the indazole ring is essentially planar [maximum deviation = 0.0192 (12) Å]. In the crystal, pairs of inter­molecular O—H⋯N hydrogen bonds link the mol­ecules into dimers lying about inversion centers and intra­molecular O—H⋯O hydrogen bonds result in six-membered rings. The dimers are further connected by N—H⋯O and O—H⋯O hydrogen bonds

    1-Methyl­amino-3-(2,4,6-trimethyl­phen­yl)propan-2-ol

    Get PDF
    The methyl­amino­propyl chain in the title compound, C13H21NO, adopts an extended zigzag conformation and the N atom shows a trigonal coordination. The N atom acts as hydrogen-bond acceptor to the hy­droxy group of an adjacent mol­ecule, generating a helical chain running along the b axis. The amino H atom is not involved in hydrogen bonding

    Poly[(μ3-rac-5-eth­oxy­carbonyl-6-hy­droxy-6-methyl-4-phenyl-4,5,6,7-tetra­hydro­benzo[c]isoxazol-3-olato)potassium]

    Get PDF
    The title compound, [K(C17H18NO5)]n, reveals the relative configuration (4R*,5S*,6R*) whereas its crystals are racemic. The cyclo­hexane ring adopts a half-chair conformation and the isoxazole ring has an envelope conformation. The ethyl fragment of the eth­oxy­carbonyl group at position 5 is disordered in a 0.547 (7):0.453 (7) ratio. The K+ ion is surrounded by five O atoms from three ligands at distances ranging from 2.606 (2) to 3.028 (2) Å, generating a three-dimensional network. The crystal packing displays inter­molecular O—H⋯N and O—H⋯O hydrogen bonds in which the hy­droxy group acts as a double proton donor

    rac-Diethyl 6-hy­droxy-4-[(2-hy­droxy­eth­yl)amino]-6-methyl-2-phenyl­cyclo­hex-3-ene-1,3-dicarboxyl­ate

    Get PDF
    The title compound, C21H29NO6, is chiral with three stereogenic centres. The crystal is a racemate and consists of enanti­omeric pairs with the relative configuration rac-(2R*,3S*,4R*). The ethyl fragment of the eth­oxy­carbonyl group at position 1 is disordered in a 0.60:0.40 ratio. The crystal packing displays inter­molecular O—H⋯O hydrogen bonding. An intra­molecular N—H⋯O hydrogen bond also occurs

    rac-Diethyl 9-hy­droxy-9-methyl-7-phenyl-1,4-diaza­spiro­[4.5]decane-6,8-dicarboxyl­ate

    Get PDF
    The title mol­ecule, C21H30N2O5, is chiral with four stereogenic centres. The crystal is a racemate and consists of enanti­omeric pairs with the relative configuration rac-(6S*,7R*,8R*,9S*). The ethyl fragment of the eth­oxy­carbonyl group at position 6 is disordered in a 0.46 (3):0.54 (3) ratio. The crystal structure features inter­molecular N—H⋯O. Intra­molecular O—H⋯N and N—H⋯O hydrogen bonds also occur
    corecore