Search results for " mixtures"
showing 10 items of 885 documents
Microbial communities in full-scale woodchip bioreactors treating aquaculture effluents.
2021
Woodchip bioreactors are being successfully applied to remove nitrate from commercial land-based recirculating aquaculture system (RAS) effluents. In order to understand and optimize the overall function of these bioreactors, knowledge on the microbial communities, especially on the microbes with potential for production or mitigation of harmful substances (e.g. hydrogen sulfide; H2S) is needed. In this study, we quantified and characterized bacterial and fungal communities, including potential H2S producers and consumers, using qPCR and high throughput sequencing of 16S rRNA gene. We took water samples from bioreactors and their inlet and outlet, and sampled biofilms growing on woodchips a…
Abnormal Lipopigments and Lysosomal Residual Bodies in Metachromatic Leukodystrophy
1990
Ultrastructurally, metachromatic leukodystrophy (MLD) is marked by characteristic features such as herringbone, prismatic and tufaceous patterns which are typically encountered within oligodendrocytes of the central nervous system (CNS) and in Schwann cells (PNS). These patterns can be documented in late infantile, juvenile, and adult forms. In the latter, aging of the ailing individual adds another component, the accumulation of lipopigments which are marked by an opaque supposedly lipid droplet and a granular component. While MLD-specific lysosomal residual bodies occur in myelinforming cells, lipopigments accrue in neurons and to a lesser degree in astrocytes. MLD represents a unique exa…
The spatial distribution of population exposure to outdoor air pollution in Valencia (Spain) and its association with a privation index
2013
Objetivo: Evaluar la variación espacial de la exposición a dióxido de nitrógeno (NO2) en la ciudad de Valencia y su relación con la privación socioeconómica y la edad. Métodos: La población por sección censal (SC) procede del Instituto Nacional de Estadística. Los niveles de NO2 se midieron en 100 puntos del área de estudio, mediante captadores pasivos, en tres campañas entre 2002 y 2004. Se utilizó regresión por usos del suelo (LUR) para obtener el mapa de los niveles de NO2. Las predicciones del LUR se compararon con las proporcionadas por: a) el captador más cercano de la red de vigilancia, b) el captador pasivo más cercano, c) el conjunto de captadores en un entorno y d) kriging. Se asi…
Activity and role of the enchytraeid worm Cognettia sphagnetorum (Vejd.) (Oligochaeta: Enchytraeidae) in organic and mineral forest soil
2003
Summary Site preparation following clear felling of coniferous forest creates a mosaic of different kinds of habitats for soil decomposers, ranging from bare mineral soil to thick layers of organic soil and felling residues. To study whether the impact of enchytraeids on nutrient mineralisation processes is different in residues, organic layer, and mineral soil, a microcosm experiment was conducted in the laboratory. Microcosms contained mineral soil (sand) alone or with soil organic layer (humus and F-layer materials) and spruce needles, either separately or together. Enchytraeids (Cognettia sphagnetorum) were introduced to the half of the microcosms. Numbers of enchytraeids, their gut con…
Vaporization Characteristics of Ethanol Droplets: Influence of the Environment Humidity
2011
The study of the gasification of a droplet via vaporization, which involves heat, mass and momentum transfer processes in gas and liquid phases, and their coupling at the droplet interface, is necessary for better understanding and modeling of complex spray and mixture formation issues. A detailed description of the vaporization of an isolated droplet has been realized in this experimental study aimed at investigating the impact of the water vapor contained in the surrounding gas on the evaporation of an ethanol droplet. The experimental set-up consists of a heated chamber with a cross quartz fibers configuration as droplet support. An ethanol droplet is located at the intersection of the c…
Direct Measurement of Particle−Bubble Interactions in Aqueous Electrolyte: Dependence on Surfactant
1998
The aim of this study was to determine the influence of surfactant on the particle−bubble interaction. Therefore we constructed an experimental setup with which the interaction between colloidal pa...
Some aspects related to stability, critical concentrations and kinetics of flocculation of the calcium phytate colloid
1986
Abstract As 99mTcCa phytate is an important radiopharmaceutical and its colloidal nature presents problems, we investigated some of them. This work describes the study of the colloidal behaviour of the calcium phytate colloid in terms of its formation, stability and kinetics of flocculation. The study of spontaneous, and centrifugation-induced flocculation allows the determination of two critical concentrations of sol flocculation. The titrations of calcium phytate colloid at different concentrations provide information on the colloidal formation conditions. Moreover, a study on flocculation kinetics was made by turbidity measurements.
Segregation in Drying Binary Colloidal Droplets
2019
When a colloidal suspension droplet evaporates from a solid surface, it leaves a characteristic deposit in the contact region. These deposits are common and important for many applications in printing, coating, or washing. By the use of superamphiphobic surfaces as a substrate, the contact area can be reduced so that evaporation is almost radially symmetric. While drying, the droplets maintain a nearly perfect spherical shape. Here, we exploit this phenomenon to fabricate supraparticles from bidisperse colloidal aqueous suspensions. The supraparticles have a core-shell morphology. The outer region is predominantly occupied by small colloids, forming a close-packed crystalline structure. Tow…
Coarse-Graining Intermolecular Interactions in Dispersions of Highly Charged Colloids
2012
International audience; Effective pair potentials between charged colloids, obtained from Monte Carlo simulations of two single colloids in a closed cell at the primitive model level, are shown to reproduce accurately the structure of aqueous salt-free colloidal dispersions, as determined from full primitive model simulations by Linse et al. (Linse, P.; Lobaskin, V. Electrostatic Attraction and Phase Separation in Solutions of Like-Charged Colloidal Particles. Phys. Rev. Lett.1999, 83, 4208). Excellent agreement is obtained even when ion-ion correlations are important and is in principle not limited to spherical particles, providing a potential route to coarse-grained colloidal interactions…
M11_Microfluidics_for_CNT
2018
The subtle solubility of water in n-decane causes leaking of the droplet content. If the n-decane flows by static droplets, it carries the water slowly away up to the total disappearance of the droplets.