Presents important principles and issues related to postpositivism including logic of confirmation and logic of falsification. Discusses possible applications in science education. Lists 23 references. (YP)

Suggests a way of distinguishing between the two classes of chemical reactions of the lanthanide series. (CS)

Reviews recent findings regarding the preovulatory surge of luteinizing hormone (LH) in the reproductive cycle. Diagrams and textual information are presented detailing aspects of the feedback loops involved in the hypothalamo-pituitary-ovarian axis. (CS)

Reviews calculations that derive an order of magnitude expression for the size of man in terms of fundamental constants, assuming that man satifies these three properties: he is made of complicated molecules; he requires an atmosphere which is not hydrogen and helium; he is as large as possible. (CS)

Reviews the application of orbital symmetry principles to an understanding of the fluxional behavior of certain organometallic compounds, with particular reference to the cyclopolyenylmetal systems. (CS)

Gives a numerical example of the steady-state assumption, using three calculations for the free radical decomposition of methane. (MLH)

Discusses the distribution of kinetic and potential energy in transverse and longitudinal waves and examines the transmission of power and momentum. This discussion is intended to aid in understanding the simple harmonic motion of a particle involved in the propagation of a harmonic mechanical plane wave. (HM)

Presents a physical inorganic experiment in which large single crystals of the alkali halides doped with divalent ion impurities are prepared easily. Demonstrates the ion pairing of inorganic ions in solid solution. (CS)

Describes an experiment for general chemistry that illustrates the use of spectroscopy in the synthesis, characterization, and nitration of tris(acetylacetonato)cobalt (III). (CS)

Describes how polydiacetylenes can be used as educational aids. These polymers have conjugated backbones, which cause changes in color when the polydiacetylenes undergo various chemical and physical processes. Diagrams summarize all chemical reactions and their associated color changes. (CS)

Presents a method suitable for intermediate level astronomy courses for the calculations of solar eclipses which avoids spherical trigonometry. (Author/CS)

Develops a coordinate-free approach to Fresnel's equations for the reflection and refraction of light at a plane interface. Describes a graphical construction for finding the vector amplitudes of the reflected and transmitted waves. (Author/CS)

Discusses a proof for determining the localized fringes position arrived at when one considers the interference of two extended sources when one is able to observe fringes only at certain points in space. Shows how the localized fringes may be found in a device used to observe Newton's rings. (Author/CS)

Discusses theories and research concerning the radiation produced by electrons when they are accelerated centripetally in particle accelerators. (MLH)

Lists the 100 most frequently prescribed drugs, providing in tabular form the trade and generic name, and a brief introduction to the nature of each drug. (MLH)