Search results for "Water"

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…

Method optimization to measure polybrominated diphenyl ether (PBDE) concentrations in soils of Bratislava, Slovakia.

2010

We modified an analytical method to determine polybrominated diphenyl ethers (PBDEs) in urban soils of Bratislava (Slovakia). Gel permeation chromatography (GPC) introduced as a clean-up step for soil extracts substantially reduced matrix enhancements when PBDEs were measured with gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS). The resulting method proved to be accurate, precise, and showed low detection limits. The sum of 15 PBDE concentrations in surface horizons of Bratislava soils ranged from 87 to 627 pg g(-1). PBDE concentrations were mostly higher in surface than deeper horizons probably because of atmospheric deposition and lack of substantial vertical…

In situ analysis of the bacterial communities associated to farmed eel by whole-cell hybridization.

1999

Bacterial communities in water samples and eel slime were investigated by fluorescence in situ hybridization of whole bacterial cells in an eel intensive culture system over 1 year. A newly developed probe, matching 27 Vibrio spp., and a specific probe for Vibrio vulnificus were used. Phylogenetic probes complementary to selected regions of the 16S and 23S ribosomal RNA revealed that Proteobacteria of the alpha and beta subclass were predominant in water and eel slime. Members of the gamma subclass (e.g. vibrios and aeromonads) were more abundant in eel slime, although no V. vulnificus was detected.

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.

Humic acid reduces gonadotropin activity and hormonal sensitivity of frog oocytes

2005

The specific stimulatory effect of sturgeon Acipenser güldenstädti Br. gonadotropic hormone (GTH) on frog Rana temporaria L. oocyte maturation in vitro was investigated in relation to humic acid (HA) concentrations from 12.5 to 50 mg/l. HA was observed to bind to both the follicular membrane of the oocytes and the GTH molecule, reducing the oocytes' hormone sensitivity and maturation ability. It was also shown that HA inactivated GTH, lowering its specific ability to stimulate oocyte maturation.

Water dissociation and water-gas shift energetics on MgO, MgO/Ag and Au/MgO/Ag surfaces

2011

Water dissociation and the energetics of the WGS reaction on a bulk MgO, an Ag supported MgO thin film and Au/MgO/Ag surfaces is studied based on the density functional theory. The literature results for water splitting on MgO and MgO/Ag surfaces with a step type defect are repeated and further analysis on the origin of the energetically favored dissociative water adsorption are made. The reactivity towards water dissociation on the stepped MgO and MgO/Ag surfaces is attributed to four contributing factors: 1. The change in the interlayer distance of the surface in dissociative adsorption is diminished on the stepped surfaces compared to the flat surfaces. On the flat surfaces the dissociat…

Evaluation of the water scarcity energy cost

2009

A New Solution for Sea Wave Energy Harvesting, the Proposal of an Ironless Linear Generator

2020

The paper investigates an innovative ironless linear generator, installable inside a wave energy converter, in order to produce electricity from sea waves. This energy source is considered strategic for the future, especially in small islands

Coupled Electric and Hydraulic Control of a PRS Turbine in a Real Transport Water Network

2019

Although many devices have recently been proposed for pressure regulation and energy harvesting in water distribution and transport networks, very few applications are still documented in the scientific literature. A new in-line Banki turbine with positive outflow pressure and a mobile regulating flap, named Power Recovery System (PRS), was installed and tested in a real water transport network for the regulation of pressure and flow rate. The PRS turbine was directly connected to a 55 kW asynchronous generator with variable rotational velocity, and coupled to an inverter. The start-up tests showed how automatic adjustment of the flap position and the runner velocity variation are able to c…

PUMP AS TURBINE (PAT) IN INTERMITTENT DISTRIBUTION NETWORKS

2012

A hydraulic model was performed in order to evaluate potential energy recovery resulting by the use of centrifugal pump as turbines (PAT) in the water distribution network characterized by the presence of private tanks. The model integrates the Enhanced Global Gradient Algorithm (EGGA) (Todini [1], Giustolisi et al. [2]), with a pressure driven model (Criminisi et al. [3]) that entails a more realistic representation of the influence of the private tanks filling and emptying process in the network behaviour. The model was applied to real case study: a district metered area in Palermo (Italy). Namely three different scenarios were analyzed and compared with the actual scenario (Scenario 0 - …