Search results for "CONTACT"

Mixed silane self assembled monolayers and their in situ modification

1998

Mixed self assembled silane monolayers were prepared by coadsorption of Br and methyl terminated trichlorosilanes. By subsequent in situ modification the Br groups were converted into amino groups which can be used to tether polyglutamates to the surface. Here we describe the characterization of the monolayers by means of contact angle measurements and X-ray photoelectron spectroscopy (XPS). Both methods clearly indicate that the Br terminated silane is preferentially adsorbed from the solution. Following the in situ modification by XPS a yield of approximately 80% was determined for the substitution of the bromine by azide, whereas the yield for subsequent reduction to the amine is close t…

Recuperación de metano disuelto en el efluente de un reactor anaerobio de lecho expandido mediante contactores de membrana

2017

La emisión de gases de efecto invernadero (GEI) a la atmósfera supone uno de los problemas medioambientales más importantes en la actualidad, debido a su relación con el calentamiento global y el cambio climático. En este sentido, uno de los GEI más relevantes es el metano, con un potencial de calentamiento global 28 veces superior al del dióxido de carbono. El sector del tratamiento de aguas residuales contribuye a las emisiones de metano, siendo de especial relevancia los tratamientos anaerobios que se llevan a cabo a temperatura ambiente. En estos sistemas, una parte del metano generado puede encontrarse disuelto en el efluente del proceso, debido al aumento de la solubilidad del metano …

Patch test results with the metalworking fluid series of the German Contact Dermatitis Research Group (DKG).

2004

Based on the information of the interdisciplinary task force on allergy diagnostics in the metal branch, in 2001, the German Contact Dermatitis Research Group (DKG) compiled two metalworking fluid (MWF) test series with currently and previously used components, respectively. After 2 years of patch testing, we present results obtained with these series, based on data of the Information Network of Departments of Dermatology (IVDK). 251 metalworkers who were patch tested because of suspected MWF dermatitis in 2002 and 2003 were included in this retrospective data analysis. Of these, 206 were tested with the current MWF series and 155 with the historical MWF series. Among the current MWF allerg…

Wip1 inhibition leads to severe pro-inflammatory phenotype in skin in response to chemical irritation

2016

Establishment and characterization of a nontumorigenic cell line derived from a human hepatocellular adenoma expressing hepatocyte-specific markers.

1997

In the present study the establishment and characterization of a nontumorigenic liver epithelial cell line (HACL-1) derived from a human hepatocellular adenoma is described. The HACL-1 cells have a finite life span (i.e., they proliferate for a period of 2 months and then senesce), show cell-cell contact inhibition, do not grow in soft agar, are not tumorigenic when injected in nude mice, and possess a normal diploid karyotype. The cultured cells resemble hepatocytes, but exhibit some features of dedifferentiation. At the ultrastructural level the cells are endowed with round or oval nuclei, abundant cytoplasmic organelles, and varying amounts of glycogen. The rough endoplasmic reticulum is…

Surface, mechanical and barrier properties of bio-based composite films based on chitosan and whey protein

2014

Mono-component and composite bilayer and blend films composed of chitosan and whey protein were made. Colour, microstructure, water contact angles, swelling, water vapour sorption, barrier properties (oxygen, water vapour), water vapour diffusion coefficients and mechanical properties were determined. The influence of water vapour on barrier properties was studied in relation to the surface and structural properties. Mono-component and bilayer films were transparent with a homogeneous surface. Contrarily, blend films were translucent. Bilayer films had significantly lower water vapour permeability in comparison to mono-component and blend films. In all bilayer films, the air side (chitosan)…

On the polymer physics origins of protein folding thermodynamics

2016

A remarkable feature of the spontaneous folding of many small proteins is the striking similarity in the thermodynamics of the folding process. This process is characterized by simple two-state thermodynamics with large and compensating changes in entropy and enthalpy and a funnel-like free energy landscape with a free-energy barrier that varies linearly with temperature. One might attribute the commonality of this two-state folding behavior to features particular to these proteins (e.g., chain length, hydrophobic/hydrophilic balance, attributes of the native state) or one might suspect that this similarity in behavior has a more general polymer-physics origin. Here we show that this behavi…

Tuning molecular self-assembly on bulk insulator surfaces by anchoring of the organic building blocks.

2013

Molecular self-assembly constitutes a versatile strategy for creating functional structures on surfaces. Tuning the subtle balance between intermolecular and molecule-surface interactions allows structure formation to be tailored at the single-molecule level. While metal surfaces usually exhibit interaction strengths in an energy range that favors molecular self-assembly, dielectric surfaces having low surface energies often lack sufficient interactions with adsorbed molecules. As a consequence, application-relevant, bulk insulating materials pose significant challenges when considering them as supporting substrates for molecular self-assembly. Here, the current status of molecular self-ass…

Wetting ability of an acetone/based etch rinse adhesive after NaOCl-treatment

2011

Objectives: to evaluate the effect of sodium hypochlorite (NaOCl) treatment on surface dentin roughness (Ra) and contact angle (CA) when using Prime&Bond NT adhesive (PB NT). Study Design: Extracted human third molars were sectioned to expose flat, superficial and deep dentin surfaces. CA and Ra were measured (1) before and (2) after 35% H3PO4 etching, and (3) H3PO4 etching + 5% NaOCl treated for 2 minutes before the application of PB NT. CA was measured by the Axisymmetric Drop Shape Analysis Technique using distilled and deionized water and PB NT. Roughness was evaluated with a profilometer, twelve radial measurements were performed in each treatment surface. Data were analyzed with two-w…

Kēmu terases Latvijas starplobu izometriskajās augstienēs

2013

Elektroniskā versija nesatur pielikumus