ChemInform Abstract: Environmental Effects on Materials: The Effect of the Air Pollutants SO2, NO2, NO and O3 on the Corrosion of Copper, Zinc and Aluminum. A Short Literature Survey and Results of Laboratory Exposures.

Clemmer and Beebe have pointed out that surface structures on graphite substrates can be misinterpreted as biopolymer images in STM experiments. We have been using electrochemical methods to react DNA fragments onto gold electrodes for STM and AFM imaging. The adsorbates produced in this way are only homogeneous in special circumstances. Searching an inhomogeneous substrate for ‘desired’ images limits the value of the data. Here, we report on a reversible method for imaging adsorbates. The molecules can be lifted onto and off the substrate during imaging. This leaves no doubt about the validity or statistical significance of the images. Furthermore, environmental effects (such as changes in electrolyte or surface charge) can be investigated easily.

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Some Effects of Oxidant Air Pollutants (Ozone and Peroxyacetyl Nitrate) on the Ultrastructure of Leaf Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095066 ◽

1972 ◽

Vol 30 ◽

pp. 360-361

Author(s):

William W. Thomson ◽

Elizabeth S. Swanson

Keyword(s):

Air Pollutants ◽

Electron Microscopic Examination ◽

Peroxyacetyl Nitrate ◽

Electron Microscopic ◽

Growth Physiology ◽

Physiology And Biochemistry ◽

Entire Plant ◽

Leaf Tissues ◽

Gaseous Hydrocarbons ◽

The Individual

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.

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Freeze-dried dispersions for automated SEM analysis of individual submicron airborne particulates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122447 ◽

1992 ◽

Vol 50 (1) ◽

pp. 408-409

Author(s):

Karen A. Katrinak ◽

David W. Brekke ◽

John P. Hurley

Keyword(s):

Air Pollutants ◽

Size Range ◽

Sem Analysis ◽

Individual Particle ◽

Chemical Data ◽

Particle Analysis ◽

Bulk Analysis ◽

Airborne Particulates ◽

Freeze Dried ◽

Individual Particle Analysis

Individual-particle analysis is well established as an alternative to bulk analysis of airborne particulates. It yields size and chemical data on a particle-by-particle basis, information that is critical in predicting the behavior of air pollutants. Individual-particle analysis is especially important for particles with diameter < 1 μm, because particles in this size range have a disproportionately large effect on atmospheric visibility and health.

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