Describes a laboratory experiment to teach the principles of air sampling, gamma ray spectroscopy, nuclear decay, and radioactive equilibrium. Analyzes radon by carbon adsorption and gamma ray counting. Provides methodology and rate of decay equations. (MVL)

States that if photochemical reactions can be followed spectrophotometrically, reactivities can be estimated by evaluating data from only one curve. Studies such a system using computerized evaluation and simulation. Uses chlorocuprate(II) complexes in acetonitrile solutions for the model systems. (MVL)

Presents a practical and attractive alternative to the sand bath used in the microscale procedures developed by Mayo, Pike, and Butcher. Urges the organic chemistry teaching community to continue towards complete conversion to microscale techniques. Presents the use of aluminum devices in the microlaboratory. (MVL)

Presents relevant statistics accumulated in a fall organic laboratory course. Discusses laboratory equipment setup to lower the amount of waste. Notes decreased solid wastes were produced compared to the previous semester. (MVL)

Describes the titration of a weak base with a strong acid and subsequent treatment of experimental data using commercially available software. Provides a BASIC program for determining first and second derivatives of data input. Lists 6 references. (YP)

Presents a device to illustrate the concepts of entropy of mixing and the contribution of one term in the Gibb's equation. Notes the device is relatively easy to construct and provides a visual demonstration on diffusion. (MVL)

Examines two computer interfaced lab experiments: 1) discusses the automation of a Perkin Elmer 337 infrared spectrophotometer noting the mechanical and electronic changes needed; 2) uses the Gouy method and Lotus Measure software to automate magnetic susceptibility determinations. Methodology is described. (MVL)

Reports on the teaching of recombinant DNA technology in high school biology courses. Explains reactions of the public, students, and colleagues to the molecular genetics unit. Indicates equipment, curricular materials, training, workshops, and availability. (RT)

Presents techniques used for disinfestation of plant material, preparation of equipment and media, and laboratory procedures for tissue culture using cauliflower. Details methods for preparing solutions and plant propagation by cloning. (CW)

Describes a technique for separating samples that range over 15 orders of magnitude in molecular weight. Discusses theory, apparatus, and sample preparation techniques. Lists several types of field-flow fractionation (FFF) and their uses: sedimentation FFF, thermal FFF, flow FFF, electrical FFF, and steric FFF. (ML)

Identifies a common laboratory problem that causes instrumentation malfunction. Provides numerous experiences of researchers whose results have been affected by humidity fluctuations, magnetic field fluctuations, trucks driving by, and other factors. (ML)

Considers three common cases of localized corrosion of metals: pitting, crevice, and stress corrosion. Provides experimental methods for studying all three methods. Includes a discussion of expected results. (ML)

Describes an experimental procedure for determining trihalomethanes (THMs) in liquids by gas chromatography. Provides recommendations for reactants and supplies to obtain acceptable results. Discusses the analysis of water from various sources: pools, lakes, and drinking water; compares these to three cola drinks. (ML)

The harmful effects of smoking tobacco are discussed. Instructions, lists of materials, and discussion questions for three activities to investigate these effects are provided. A glossary of tobacco-use terms is given. (CW)

A study of 36 first-year Northwestern University (Illinois) medical residents found that students' medical knowledge was a predictor of increased laboratory test use, that clinical judgment was a predictor of decreased laboratory use, and that level of caring was statistically unrelated to amount of laboratory use. (Author/MSE)