This article discusses the toxic effects of inhalation of gallium arsenide, indium arsenide and indium phosphide dusts. Exposure to these semiconductor compounds in the microelectronic industry can occur during the preparation of materials, cleaning and maintenance operations. The article discusses the limited findings about routes of exposure and effects on biological systems including pulmonary, ... Full description.

This site is a lecture from Tulane University that explores atoms and how they interact with one another to determine the physical and structural properties of crystals. Topics include atoms, isotopes, the quantum mechanical view of the atom, the electronic structure of atoms, ions, electronegativity, and various types of bonds that bind the atoms together in a crystal structure. Tables and illustrations ... Full description.

Once a website for online, one-on-one tutoring, Technical Tutoring is now a repository of help pages developed by Phil Otken. Examples and lessons on many aspects of calculus, algebra, trigonometry, and basic chemistry. Each lesson includes a concise discussion and step-by-step intructions, formulas, and figures. This resource is part of the Teaching Quantitative Skills in the Geosciences collection. ... Full description.

The goal of the Computers in Chemistry at Cabrillo College (C4) Project is to improve the learning of chemical concepts through the use of computer visualization. C4 produces and disseminates software to be used in chemistry and biology classrooms, both in colleges and high schools. The project specializes in the design and educational use of molecular visualizations and animations. C4 is producing ... Full description.

This resource from Dr. Terry Frey at San Diego State University is an abbreviated introduction to crystallography and x-ray diffraction. Topics include an overview, crystal growth, crystal classes and symmetry, two descriptions of diffraction, experimental approaches, and other x-ray diffraction methods. Illustrations and diagrams are also incorporated into the article. Full description.

This report summarizes the current knowledge of naturally occurring radioactive materials in oil-fields of the United States. Of particular concern is the effect on public health and the environment of exposure to radioactive materials in the form of radium-bearing water and 'scale' deposits in tanks and pipes, which may travel far from the oil fields as scrap metal products. Full description.

This USGS site provides access to data sets collected by the National Water-Quality Assessment Program. It features fact sheets, reports, bibliographies, additional data sets and links to other resources about nutrients in streams, rivers and aquifers of the United States. The site briefly explains what nutrients are, how they are used in the agricultural industry, how they react chemically in the ... Full description.

The goal of this introductory college level exercise is to get students to characterize the phenomenon of the ozone hole on their own. This is an inquiry-based activity designed to spark student interest, curiosity, and a desire to understand the causes of this atmospheric problem. A multitude of rich data sets are accessible to students. There are several sections, each linked with data sets and ... Full description.

The biocomplexity institute at Indiana University is a collaborative effort among several academic departments. The institute is active in the areas of research, communication and outreach, software and resources, and training of scientists. This web site provides in-depth information on research projects, bioimaging, bioinformatics, biocomplexity in the curriculum, and more. The site also features ... Full description.

This fact sheet provides general information about elemental chromium, including types of chromium, uses, and the effects of short-term and long-term exposure. Full description.