Major instrumental concerns in molecular solution fluorimetry have recently turned away from sensitivity enhancement to an orientation more directed toward selectivity. This trend simply recognizes that such methodology has historically been blank limited. Thus, the described uses of liquid chromatography, line narrowing, and time resolution…

Discusses two newer methods in mass spectrometry and shows how they can increase signal and signal-to-noise ratios, respectively. The first method, desorption ionization (DI), increases sensitivity while the second method, mass spectrometry/mass spectrometry (MS/MS), increases specificity. Together, the two methods offer improved analytical…

Three chemistry demonstrations are described: (1) partition coefficients; (2) Rutherford simulation experiment; and (3) demonstration of the powerful oxidizing property of dimanganeseheptoxide. Background information, materials needed, and procedures are provided for each demonstration. (JN)

Background information, procedures, and typical results are provided for an experiment which integrates principles of fluorescent and kinetic analysis. In the procedure, mecuric chloride is used as a selective oxidizing agent for converting thiamine to thiochrome. The experiment can be completed in a two-hour laboratory period. (Author/JN)

Describes a straight-forward and relatively inexpensive method for routine isolation of purified soybean agglutinin, suitable for use as a starting material in most studies, especially for fluorescent-labeling experiments. The process is used as a project to provide advanced laboratory training at a two-year college. (Author/JN)

Highlights the background, career, and major accomplishments of Robert Allan Weinberg, professor of Biology at the Massachusetts Institute of Technology. His accomplishments and research interests focus on oncogenes, genes capable of causing cancer. The discovery of these genes has revealed the central mechanism of cancer. (Author/JN)

Topics in this discussion of photorespiration (light-dependent oxygen consumption and carbon dioxide evolution from leaves) include: (1) the biochemistry of photorespiration; (2) ribulose biphosphate carboxylase and glycollate synthesis; (3) metabolism of glycollate; (4) plants lacking photorespiratory systems; and (5) advantages of…

Describes a 10-week survey course in catalysis for chemical engineering and chemistry students designed to show how modern chemistry and chemical engineering interact in the ongoing development of industrial catalysts. Includes course outline and instructional strategies. (Author/JN)

An oilwell drilling rig accidentally drilled into an underground salt mine, draining a lake and filling the mine, with water jetting out of the mine 400 feet into the air. An explanation of the jetting phenomenon is offered in terms of the laws of fluid dynamics, with supporting diagrams and calculations. (Author/JN)

Describes a simple method to determine potential chemical formulas for a given molecular weight and to calculate all of the typical mass spectrometric parameters which can be obtained experimentally. Calculated values can then be compared to experimental values to obtain the most reasonable formula. (JN)

An approach is described in which accurate weighings are provided under circumstances when samples cannot be placed directly on a balance pan. The approach, based on external weighing, uses a new simple apparatus designed for any kind of analytical balance and not requiring a hole through the base of the balance. (JN)

The syllabus for a refresher course on the physiology and biochemistry of receptors (presented at the 1983 American Physiological Society meeting) is provided. Topics considered include receptor regulation, structural/functional aspects of receptors for insulin and insulin-like growth factors, calcium channel inhibitors, and role of lipoprotein…

Presented is a possible approach to the classroom treatment of enzyme kinetics at the two-substrate level. Areas discussed include single substrate cases, two substrate cases, Cleland's rules, dead end inhibition, inhibitor complexing with more than one enzyme form, and product inhibition. (JN)

Oxidation of magnesium metal in air has been used as an introductory experiment for determining the formula of a compound. The experiment described employs essentially the same laboratory procedure but is significantly more advanced in terms of information sought. Procedures and sample calculations/results are provided. (JN)

Describes a gas chromatographic experiment for the quantitative determination of volume percent ethanol in water ethanol solutions. Background information, procedures, and typical results are included. Accuracy and precision of results are both on the order of two percent. (JN)