Foam Particles Research Articles

The Health Cost of 'Tight' Homes

Home insulation means energy conservation. How can one find fault with a concept that, it is hoped, will allow us to reduce our dependence on foreign oil? Unfortunately, the present energy conservation program as it applies to building structures and, most important, to homes involves making our habitable structures as tight as possible. There is no doubt that unless a reasonable and logical plan is developed, the deleterious health impacts of excessive home tightening will be enormous. The use of urea formaldehyde foam insulation and particle board resulting in long-term formaldehyde release simply highlights some of these consequences (see p 243). Formaldehyde's potential for causing skin disease has been well documented: it can induce dermatitis by irritation, delayed-type hypersensitivity, and immediate urticarial reactions. It can result in irritation of the eyes and upper respiratory tract. Formaldehyde has also been incriminated in the induction of an inflammatory bronchitis and bronchial asthma.

Immobilized organelles and whole cells into protein foam structures: Scanning and transmission electron microscope observations

Protein foam structures bearing cells and organelles were produced by using a co-crosslinking method with serum albumin and glutaraldehyde at sub-zero temperature. Morphological observations obtained with scanning and transmission electron microscopy indicate macroporous and homogeneous structures. The glutaraldehyde concentration was varied to reveal its effect on immobilized red cells. It was observed that the structural appearance of preatreated cells or subcellular fractions (thylakoids from lettuce ; spheroplasts and chromatophores from R. capsulata) is preserved during the immobilization process. The morphological features of foam particles are always related to the observed kinetic activities of the specimens.

Area/volume configuration influence on porous material outgassing

Outgassing data is introduced for some circumjacent cellular materials and stranded elastic cords used for the shock mitigation of experiments in chambers evacuated to 1 mTorr. The influence of area/volume configuration ratios and the effect of humidity sorption on carbonaceous foam outgassing is shown for pumpdown elapsed-time durations to 10 h, and for A/V ratios from 0.4 to 0.8 cm−1. Combined outgassing and virtual leakage data, from test specimens which were loosely wrapped to control carbon foam particle migration and vacuum pump oil contamination, is discussed. Other test specimens investigated, which had A/V ratios from 0.4 to 4.2 cm−1, are polyurethane foam, aluminum–alloy honeycomb, elastic shock absorber (bungee) cord, and distended-surface steel plate. A cascading chart is presented for lucid determination of outgassing rates from these materials. Outgassing coefficients developed from this data for modeling are referenced.

99mTc-Markierung von Gelatineschwamm für die Katheterembolisation

A simple method is described for marking gel foam particles with 99mTc after reduction of the pertechnetate. This is carried out in the Luer lock syringe to be used for the injection. After embolisation and control angiography, the patient is placed under a scintillation camera. The position of the embolising material can then be demonstrated scintigraphically. In six patients marked emboli were found to be correctly placed. In another patient undergoing a second embolisation for a renal tumour, particles were found in the peripheral circulation.

Particulate oil spill recovery. I, Oil sorption properties of plastic foams

Reusable, reticulated, polyurethane foams are broadcast at sea, absorb oil in the presence of water, are recovered, oil removed and foam particles rebroadcast. Combining dimensional and mathematical analysis with experimental data, a mathematical model of foam sorption efficacy and rate is developed showing the system to be practical. Oil viscosity, wave height, recovery ship speed, and system geometry influence foam selection.

Influence of Drying Methods on Density and Porosity of Milk Powder Granules

Summary Gas and liquid displacement techniques were used to determine the true and apparent densities as well as the relative porosities of milk powder granules produced by various drying techniques. Using helium as the displacing gas, rapid penetration of conventional spray-dried, spray-dried foam and vacuum-dried foam particles was noted; all whole milk powders had true densities averaging 1.30 g/cm 3 . By this method, the measured true density of a commercial instantized skimmilk powder was 1.48 g/cm 3 . When hydrogen, nitrogen, decalin, or mercury was used as a displacing medium, data were obtained showing a wide variation in the porosity of particles produced by different drying techniques. It was concluded that conventional spray-dried material contained small amounts of occluded gas exchanged only with great difficulty, if at all. Spray-dried foam particles contain relatively large volumes of gas which can undergo exchange slowly and completely. The small quantities of trapped gas in vacuum foam-dried particles can undergo rapid and complete exchange.