Thermal weed control plays an important role in managing weeds synthetic herbicide-free systems, particularly organic agriculture and urban areas where herbicides are prohibited. This study compares the impact on of increased doses hot water foam (i.e. 0, 0.67, 1.67, 3.33, 5.00, 6.67 8.33 kg m–2). The were applied using same machine. temperatures, effectiveness, regrowth after death aboveground...

the importance of the use of activated charcoal tubes for sampling gases and vapors is very well-known. for producing these tubes in the country, their production started in the laboratory of the department of occupation al health using activated charcoal, polyurethane foam and glass wool and consequently two types of foamed and foamless tubes were produced. to investigate the quality of the ra...

In this paper, a new anisotropic material concept namely composite foam is proposed as an alternative to next generation helmet liners which can potentially reduce head rotational accelerations. The Layered Composite foam concept comprises of foam layers with different densities which are glued to each other in a parallel or series configuration. Initial experiments such as static combined shea...

Negative Poisson's ratio foam was used in the development of seat cushions which exert reduced peak pressure upon the skin of seated persons. Foam processing techniques were scaled up. A longer processing time was required for cushion size samples in comparison with small samples. Pressure distributions on a seated subject were measured using a pressure-sensitive array. Seated pressure distribu...

Performance advantages of incorporating fluid channels into foam made of DERTEX VN600 (Vinyl Nitrile) are evaluated. This foam has the potential to replace the traditional foam material of helmet liners, like Expanded Polystyrene (EPS). Experiments involved dropping a certified size E headform vertically onto a flat, solid anvil. Elastically deformable and resilient VN foam outperformed EPS dur...

Finite Element Analysis (FEA) was used to model viscoelastic effects in the compression of polyurethane (PU) foam. Modelling of the impact compression of foam cubes predicted that a compressed region propagated through the sample, causing step increases in the stress traces. Modelling of head impacts on gymnastic ‘crash’ mats, made of PU chip foam, revealed that the majority, but not all, of th...

Fundamental studies of surface forces in foam films are carried out to explain the stability of foams and froths in froth flotation. The thin film pressure balance (TFPB) technique was used to study the surface forces between air bubbles in water from equilibrium film thickness and dynamic film thinning measurements. The results were compared with the disjoining pressure predicted from the Derj...

This thesis presents experimental work on foam/sand mixtures carried out in the Civil The first chapter deals with basic aspects of soil conditioning agents and their application to tunnelling, and provides an understanding of the fundamentals of foam behaviour. An introduction to the problems encountered in tunnelling is given. A brief study of foams and their properties is presented and the r...

CONTEXT Poor balance has been associated with increased injury risk among athletes. Neuromuscular-training programs have been advocated as a means of injury prevention, but little is known about the benefits of these programs on balance in high school athletes. OBJECTIVE To determine whether there are balance gains after participation in a neuromuscular-training program in high school athlete...

This paper presents a numerical study of microwave scattering and emission from a foamcovered ocean surface. The foam layer is modeled as an inhomogeneous layer with randomly rough airfoam and foam-seawater boundaries. Kelvin’s Tetrakaidecahedron structure is selected as the skeleton for simulating the air bubbles in the foam layer. The electromagnetic characteristics of the foam layer, includi...