Antimicrobial poly(vinyl alcohol) nanofibres are produced using AquaQure biocide as additive to the polymer solution. AquaQure is an aqueous antimicrobial agent containing mainly Cu2+ and Zn2+. Antimicrobial tests show that the fibres achieve up to a 5 log reductions in populations of E. coli, S. aureus, S. typhimurium, P. aeruginosa and K. pneumoniae bacteria. Reusability of the nanofibre membranes is investigated to establish if the nanofibres retain their morphology and antimicrobial effectiveness over six cycles of water filtration. Leaching of AquaQure constituents from the nanofibres into filtered water is assessed and found to be at acceptable levels.
Studies have been conducted with respect to the generation of fine‐disperse aerosols with the use of an explosive disperser model based on hydrodynamic shock tube. The physicomathematical model for the process of explosive dispersion with the aforesaid design is described [1]. The use of elements in the model design to produce cavitation bubbles under the action of shock wave and ensurance of slower outflow process of a water‐steam mixture makes it possible to obtain liquid disperse aerosols. The experimental results for aerosol disperse parameters and the processes of initiation and propagation of an aerosol cloud produced upon explosive dispersion of a variety of liquids and condensed powders are presented. Pressure values in the combustion chamber of the disperser, velocity of aerosol particles, and aerosol disperse parameters were obtained. The design of the explosive disperser with a nozzle, which provides favorable conditions for cavitation processes inside the dispersed liquid, is shown to allow the generation of a high dispersity aerosol (about 1–100 nm), which is essential for many practical problems. The function of distribution of such particles by size cannot be measured reliably and directly by methods available; however, indirect experiments (measurement of humidity when dispersing water) permit estimating the existence of particles in the aerosol with sizes below 1 μm in quantity of approx. 90 %. 相似文献
The present study examined whether training in cognitive coping skills would enhance pain coping strategies and alter pain perception in adults with sickle cell disease (SCD). Sixty-four African Americans with SCD were randomly assigned to either a cognitive coping skills condition (three 45-min sessions in which patients were trained to use 6 cognitive coping strategies) or a disease-education control condition (three 45-min didactic-discussion sessions about SCD). Pain sensitivity to calibrated noxious stimulation was measured at pre- and posttesting, as were cognitive coping strategies, clinical pain, and health behaviors. Results indicated that, compared with the randomly assigned control condition, brief training in cognitive coping skills resulted in increased coping attempts, decreased negative thinking, and lower tendency to report pain during laboratory-induced noxious stimulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
A rapidly scanning lidar system, the Laser Cloud Mapper (LCM), was operated to determine and assess its sensitivity as well as its mapping capability for the remote characterization of airborne biological organisms. Both field and aerosol chamber experiments were conducted. The test bioaerosol was produced by aerosolization of aqueous suspensions of Bacillus subtilis var. niger sp. globiggi (BG) in spore form; the relative concentration (by volume) of BG spores in tap water was varied from 0.001 to 100%. In a few additional trials, other biological simulants were studied. The statistical procedures formulated to analyze the linear depolarization ratios derived from the lidar data, and the results of this analysis are described with the objective of characterizing the biodetection capabilities and limitations (e.g., lower limits of detection, minimum mean time to detection for a given mean time between false alarms, etc.) of the LCM. 相似文献
A variety of terms are used to describe phytoplankton cell size fractions in the freshwater and marine literature. To eliminate misinterpretations, it is strongly suggested that a uniform terminology be adopted by limnologists and phycologists working in the Great Lakes. This terminology is in accord with SI units of dimension and mass. Some examples of the importance of picoplankton are discussed. 相似文献
