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Variations in the physical properties of surf generated aerosols with altitude

100%

Zieliński T.

Oceanologia

2003

tom No. 45 (4)

643-653

Vertical profiles of marine aerosol size distribution and concentration in the marine boundary layer over surf zones depend strongly on wind speed, direction and duration as well as the sea bottom profile. The measurements in the present study were carried out in various seasons of the year with all these factors being taken into consideration. The data with respect to offshore winds were neglected in the calculations, since in such cases the major aerosol contribution was from terrigenous and anthropogenic particles. It was confirmed that in the range of wind speeds from 1 m s-1 to 12 m s-1 there were measurable differences in the concentrations, particularly in the size distribution of marine aerosol particles at two stations differing with respect to their sea bottom profiles.

Variations in the physical properties of surf generated aerosols with altitude

75%

Zielinski T.

nr 4

Vertical profiles of marine aerosol size distribution and concentration in the marine boundary layer over surf zones depend strongly on wind speed, direction and duration as well as the sea bottom profile. The measurements in the present study were carried out in various seasons of the year with all these factors being taken into consideration. The data with respect to offshore winds were neglected in the calculations, since in such cases the major aerosol contribution was from terrigenous and anthropogenic particles. It was confirmed that in the range of wind speeds from 1 m s−1 to 12 m s−1 there were measurable differences in the concentrations, particularly in the size distribution of marine aerosol particles at two stations differing with respect to their sea bottom profiles.

A System for Measuring Vertical Concentration Profiles of Gaseous Pollutants, Using Carbon Dioxide as a Case Study

63%

Micallef A. , Deuchar C. N. , Colls J. J.

1998

tom Vol. 4, No. 3

333--346

An electronically-controlled sampling system, characterised by its organ pipe design, has been developed for sampling air sequentially, at different heights within the breathing zone. Data are automatically logged at the different receptor levels, for the determination of the average vertical concentration profile of gaseous pollutants. The system has been coupled to a carbon dioxide monitor and used in a brief study of the spatial and temporal variation of indoor carbon dioxide concentration. The system can easily be extended for different heights or modified for use with other types of gas monitor. The results of a trial run, which was carried out in a coffee room, are presented and applications of the Organ Pipe Sequential Sampling (OPSS) system are discussed.

Theoretical approach to the physics of fuel cells

51%

Wijewardena Gamalath K. A. I. L. , Peiris B. M. P.

tom Vol. 2

15-27

Ion transport rate of PAFC, AFC, PEMFC, DMFC and SOFC fuel cells under the influence of an electric field and concentration gradient were evaluated for static electrolytes. AFC are the best fuel cells for high er current applications while direct methanol fuel cells DMFC are the best for lower current applications AT lower temperatures. An equation for voltage output of a general fuel cell was obtained in terms of temperature and partial pressure of reactants. Performance of a 2D fuel cell was analyzed by simulating polarization and power curves for a fuel cell operating at 60 ?C with a limiting current density of 1.5 A cm- 2. The maximum power for this fuel cell was 8.454 W delivering 82% of maximum loading current density. When the temperature was increased by one third of its original value, the maximum power increased by 6.75% and at 60 ?C for a 10 times increment of partial pressure of reactants, the maximum power increased by 2.43%.The simulated power curves of the fuel cells were best described by cubic fits.