Search results for " Industry"
showing 10 items of 2376 documents
Hybrid layers of etch-and-rinse versus self-etching adhesive systems.
2010
Objective: To evaluate the effectiveness in the formation of resin tags, adhesive lateral branches and hybrid layers of five adhesive systems, when bonding to dentine. Material and Methods: Flat dentin surfaces from 25 molars were bonded with several adhesive systems according to the manufacturers? instructions. Composite build-ups were constructed incrementally with Tetric Ceram. The Specimens were sectioned parallel to the long axis. One section was treated with phosphoric acid and sodium hypochlorite in order to reveal the hybrid layer formation. The other section was stored in 30% hydrochloric acid to detect resin tags and adhesive lateral branch formation. Results: The two etch-and-rin…
Upgrading landfill gas using a high pressure water absorption process
2014
Abstract The upgrading of landfill gas (methane 54.2 ± 2.0%, carbon dioxide 42.1 ± 2.4% and nitrogen 3.7 ± 1.2%) was studied with a pilot-scale high pressure water absorption system consisting of absorption, desorption and gas drying units. The gas was upgraded in two phases and with two absorption columns operating in sequence in pressures up to 180 bar, and with initial pressures of 8 and 10 bar. This type of high pressure process, where water is used for increasing the gas pressure, does not need a separate compression unit to produce the gas pressure required by gas vehicles. Product gas with a methane contents ranging from 83.0% to 92.1% was achieved with differing process parameters, …
Modeling the anaerobic treatment of sulfate rich urban wastewater. Application to AnMBR technology
2020
[EN] Although anaerobic membrane bioreactors (AnMBR) are a core technology in the transition of urban wastewater (UWW) treatment towards a circular economy, the transition is being held back by a number of bottlenecks. The dissolved methane released from the effluent, the need to remove nutrients (ideally by recovery), or the energy lost by the competition between methanogenic and sulfate-reducing bacteria (SRB) for the biodegradable COD have been identified as the main issues to be addressed before AnMBR becomes widespread. Mathematical modeling of this technology can be used to obtain further insights into these bottlenecks plus other valuable information for design, simulation and contro…
Double Thermoresponsive Block Copolymers Featuring a Biotin End Group
2010
A poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N-isopropyl methacrylamide) (POEGMA-b-PNIPMAM) block copolymer with a biotin end group on the PNIPMAM block as a biotarget was synthesized as a model system for temperature-controlled polymer immobilization. The synthesis was based on RAFT polymerization followed by postpolymerization modification of an activated ester precursor block and an exchange of the dithioester end group within one step. NMR, differential scanning calorimetry (DSC), dynamic light scattering (DLS), and turbidimetry measurements were performed to investigate the stimulus-responsive properties. The double thermoresponsive POEGMA-b-PNIPMAM with biot…
Molecular Recognition by Hydrogen Bonding in Polyelectrolyte Multilayers
1997
Functional polyanions were prepared by copolymerization of sulfopropyl acrylate and sulfopropyl methacrylate with monomers bearing triaminopyrimidine or barbituric acid functionalities, respectively. Functionalized polyelectrolyte multilayers were assembled from these copolymers by stepwise alternating adsorption with poly(choline methacrylate). These multilayers are suited for molecular recognition of substrates that are complementary to the functional groups incorporated. Thus, multilayers containing triaminopyrimidine moieties selectively bind barbituric acid, and vice versa, when exposed to solutions of the 1:1 complex of barbituric acid and triaminopyrimidine. The molecular recognition…
Poly(ethylene oxide)-block-poly(n-butyl acrylate)-block-poly(acrylic acid) triblock terpolymers with highly asymmetric hydrophilic blocks: synthesis …
2013
The synthesis and aggregation behaviour in aqueous media of novel amphiphilic poly(ethylene oxide)-block-poly(n-butyl acrylate)-block-poly(acrylic acid) (PEO–PnBA–PAA) triblock terpolymers were studied. Terpolymers composed of two highly asymmetric hydrophilic PEO (113 monomer units) and PAA (10–17 units) blocks, and a longer soft hydrophobic PnBA block (163 or 223 units) were synthesized by atom transfer radical polymerisation (ATRP) of n-butyl acrylate and tert-butyl acrylate (tBA), followed by selective hydrolysis of the PtBA blocks. These terpolymers are not directly soluble in water but form defined spherical micelles by employing the dialysis method as confirmed by dynamic light scatt…
A fluorescence spectroscopy study of the interaction of monocationic quinine with phospholipid vesicles Effect of the ionic strength and lipid compos…
1997
Abstract The interaction of monocationic quinine with zwitterionic dimyristoyl phosphatidylcholine (DMPC) and mixed negatively-charged dimyristoylphosphatidyl glycerol (DMPG) DMPC small unilamellar vesicles in the liquid-crystalline phase was investigated by steady-state fluorescence spectroscopy at pH 7 and 37°C. The maximum fluorescence emission peak at 383 nm, upon excitation at 335 nm, shifts to lower wavelength and decreases its intensity as the ratio between the total lipid and quinine concentrations increases. This indicates that in the membrane-bound state quinine is in an environment of low polarity, more deeply buried when anionic DMPG is present in the vesicle. For monoprotonated…
Trends in individual reimbursement of orphan drugs in Latvia in 2008–2011
2014
Orphan drugs (ODs) are medicinal products intended for diagnosis, prevention or treatment of life-threatening or very serious diseases affecting less than 5 in 10 000 people in the European Union (EU). These drugs are called “orphans” because the pharmaceutical industry has little interest, under normal market conditions, in developing and marketing products intended for only a small number of patients suffering from very rare conditions. Because of the small market, ODs are often very expensive. Whereas decisions surrounding orphan designation and marketing authorization of ODs are taken at the EU level, decisions governing pricing and reimbursement of ODs are a member state responsibility…
Factors affecting the choice of cooking fuel, cooking place and respiratory health in the Accra metropolitan area, Ghana.
2005
Indoor air pollution resulting from the combustion of solid fuels has been identified as a major health threat in the developing world. This study examines how the choice of cooking fuel, place of cooking and behavioural risk factors affect respiratory health infections in Accra, Ghana. About 65·3% of respondents use charcoal and 4·2% use unprocessed wood. A total of 241 (25·4%) respondents who cook had had respiratory health symptoms in the two weeks preceding the study. Household socioeconomic status and educational attainment of respondents were found to have a significant impact on respiratory health through their particular influence on the choice of cooking fuel. Households that use w…
Food packaging cues as vehicles of healthy information: Visions of millennials (early adults and adolescents)
2018
Abstract Because packaging has become an important marketing tool, firms must know what type of packaging can affect consumers' packaging cues. Also, still today there is little attention paid to the relevance of educating millennials about the importance of a healthier lifestyle and eating. The aim is to analyse the effects of young consumers with varying degrees of healthy lifestyles and food involvement on packaging cues. Also, the paper analyses differences between early adults and adolescents millennials. Using a sample of 890 millennials (300 early adults and 590 adolescents) and SEM methodology, interesting results are reached. Some healthy habits affect food involvement, and this is…