Interactions between an immobilized, heparin-derived octasaccharide and growth factors have been observed using a quartz crystal microbalance-dissipation (QCM-D). This device can measure the amount of growth factors binding to the octasaccharide surface and also the change of dissipation of the surface. Dissipation is a measure of how the adhered material 'damps' the surface vibrations. The oct...

In view of the increased importance attached to the gravimetric sampling of airborne dust in mines and other working places, it was recently decided to start regular gravimetric sampling in the experimental animal dusting rooms in this Unit. As no suitable sampling instrument was available, a Hexhlet dust sampler was modified by fitting it with a probe in place of the elutriator. This instrumen...

In recent work [1], we introduced a new, linear-programming based method, for detecting underground features based on gravity measurements. The current paper takes this method one important step further, in that it makes it work under realistic conditions, where most of the physical characteristics of the environment are not known. In particular, the ADCS algorithm we introduce works when the f...

Particulate air pollution, specifically the fine particle fraction (PM2.5), has been associated with increased cardiopulmonary morbidity and mortality in general population studies. Occupational exposure to fine particulate matter can exceed ambient levels by a large factor. Due to increased interest in the health effects of particulate matter, many particle sampling methods have been developed...

N-Phenylbenzohydroxamic acid (PBHA) and its derivatives are widely employed as gravimetric reagents for many metal ions15• PBHA has also been reported as a reagent for the gravimetric estimation of copper and cobalt6• However it has been found that the introduction of electrophilic substituents like chlo.riine on the N-phenyl ring of the hydroxamic acid renders the reagent more selective due to...

Studies were carried out to evaluate a gravimetric method for the determination of soil organic matter by the mass loss at 300C. The gravimetric method was compared with Walkley-Black, using several brazilian soils with variable chemical and physical properties. Gravimetric method was positively correlated with Walkley-Black method with the following linear regression equation: y = 3.72x + 0.29...

A significant difference between the reported volumes delivered by a fluid-filled automated liquid-handling system with eight stainless steel fixed tips was observed when a gravimetric method and a dual dye photometric method were used to measure delivered volumes between 20 and 200 microL. A series of experiments, using the default pipetting parameters, was performed which demonstrated that th...