Search results for "Roca"
showing 10 items of 1893 documents
Effect of rhamnolipids on microbial biomass content and biochemical parameters in soil contaminated with coal tar creosote
2019
AbstractThe objective of the present study was to compare the effect of rhamnolipids on the microbial biomass content and the activity of dehydrogenases (DHA), acid phosphatase (ACP), alkaline phosphatase (ALP), and urease (URE) in soil contaminated with two types of coal tar creosote: type C and type GX-Plus. The experiment was carried out on samples of sandy clay loam under laboratory conditions. Coal tar creosote was added to soil samples at a dose of 0 and 10 g·kg−1 DM, along with rhamnolipids at a dose of 0, 10, 100, and 1000 mg·kg−1 DM. The humidity of the samples was brought to 60% maximum water holding capacity, and the samples were incubated at 20°C. Microbial and biochemical param…
Electrochemical characterization of praseodymia doped zircon. Catalytic effect on the electrochemical reduction of molecular oxygen in polar organic …
2011
The voltammetry of microparticles and scanning electrochemical microscopy methodologies are applied to characterize praseodymium centers in praseodymia-doped zircon (PrxZr(1−y)Si(1−z)O4; y + z = x; 0.02 < x < 0.10) specimens prepared via sol–gel synthetic routes. In contact with aqueous electrolytes, two overlapping Pr-centered cathodic processes, attributable to the Pr (IV) to Pr (III) reduction of Pr centers in different sites are obtained. In water-containing, air-saturated acetone and DMSO solutions as solvent, PrxZr(1−y)Si(1−z)O4 materials produce a significant catalytic effect on the electrochemical reduction of peroxide radical anion electrochemically generated. These electrochemical…
Critical micellisation density: a SAS structural study of the unimer–aggregate transition of block-copolymers in supercritical CO2
2000
In this paper we report a SANS investigation of micelle formation by fluorocarbon-hydrocarbon block copolymers in supercritical CO2 (scCO2) at 313K. A sharp unimer-micelle transition is obtained due to the tuning of the solvating ability of scCO2 by profiling pressure. At high pressure the copolymer is in a monomeric state with a random coil structure. By lowering the pressure aggregates are formed with the hydrocarbon segments forming the core and the fluorocarbon segments forming the corona of spherical aggregates. This aggregateunimer transition is driven by the gradual penetration of CO2 molecules toward the core of the aggregate and is critically related to the density of the solvent, …
Reduced graphene oxide-based magnetic composite for trace determination of polycyclic aromatic hydrocarbons in cosmetics by stir bar sorptive dispers…
2020
This work describes a sensitive and rapid analytical method for trace determination of polycyclic aromatic hydrocarbons (PAHs) in cosmetic samples. The proposed method is based on stir bar sorptive-dispersive microextraction (SBSDME). A magnetic composite made of CoFe2O4 magnetic nanoparticles embedded into reduced graphene oxide sheets is used as sorbent phase. After the extraction, the target analytes are desorbed in toluene and then analyzed by gas chromatography-mass spectrometry (GC-MS). The main parameters involved in the extraction procedure (i.e., composite amount, extraction time and desorption time) were evaluated and optimized to provide the best extraction efficiency. The method…
Passive sound exposure induces rapid perceptual learning in musicians: event-related potential evidence.
2013
Musicians show enhanced auditory processing compared to nonmusicians. However, the neural basis underlying the effects of musical training on rapid plasticity in auditory processing has not been systematically studied. Here, the rapid (one session) learning-related plastic changes in event-related potential (ERP) responses for pitch and duration deviants between passive blocks were compared between musicians and nonmusicians. Passive blocks were interleaved with an active discrimination task. In addition to musicians having faster and stronger overall source activation for deviating sounds, source analysis revealed rapid plastic changes in the left and right temporal and left frontal source…
CCDC 257719: Experimental Crystal Structure Determination
2005
Related Article: S.Floquet, A.J.Simaan, E.Riviere, M.Nierlich, P.Thuery, J.Ensling, P.Gutlich, J.-J.Girerd, M.-L.Boillot|2005|Dalton Trans.||1734|doi:10.1039/b418294d
CCDC 257718: Experimental Crystal Structure Determination
2005
Related Article: S.Floquet, A.J.Simaan, E.Riviere, M.Nierlich, P.Thuery, J.Ensling, P.Gutlich, J.-J.Girerd, M.-L.Boillot|2005|Dalton Trans.||1734|doi:10.1039/b418294d
CCDC 209379: Experimental Crystal Structure Determination
2004
Related Article: K.I.Nattinen, K.Rissanen|2003|CrystEngComm|5|326|doi:10.1039/b307875b
CCDC 257721: Experimental Crystal Structure Determination
2005
Related Article: S.Floquet, A.J.Simaan, E.Riviere, M.Nierlich, P.Thuery, J.Ensling, P.Gutlich, J.-J.Girerd, M.-L.Boillot|2005|Dalton Trans.||1734|doi:10.1039/b418294d
CCDC 257713: Experimental Crystal Structure Determination
2005
Related Article: S.Floquet, A.J.Simaan, E.Riviere, M.Nierlich, P.Thuery, J.Ensling, P.Gutlich, J.-J.Girerd, M.-L.Boillot|2005|Dalton Trans.||1734|doi:10.1039/b418294d