BIBLIOGRAPHICAL CITATION CHARACTERISTICS OF THE PSYCHOLOGICAL JOURNAL NETWORK IN 1950 AND IN 1960.

THE FLOW OF INFORMATION EXCHANGE AMONG 21 PSYCHOLOGICAL JOURNALS, AS INDEXED BY RECIPROCAL CITATION FREQUENCIES, WAS STUDIED AS A COMMUNICATION NETWORK BY THE APPLICATION OF INFORMATION THEORY AND OTHER STATISTICS. JOURNALS BEING CITED WERE TREATED AS SOURCES OF INFORMATION WITHIN THE NETWORK AND JOURNALS DOING THE CITING WERE TREATED AS DESTINATIONS OF INFORMATION. THE CHARACTERIZATION OF THIS NETWORK, FOR 1959 AND 1960, WAS IN TERMS OF SUCH MEASURES AS: TRAFFIC (NUMBER OF MESSAGES EXCHANGED), CONGRUENCE (CORRELATIONS BETWEEN SOURCE AND DESTINATION PROBABILITIES), FEEDING VS. STORING FUNCTIONS (RATIOS OF BEING CITED TO CITING), SELF-FEEDING (SELF-CITATION OF JOURNALS), SOURCE AND DESTINATION BALANCES (ENTROPY MEASURES, H, FOR BEING CITED AND CITING ACROSS THE NETWORK), AND NETWORK ORGANIZATION (CONDITIONED PREDICTABILITY OF DESTINATION JOURNAL GIVEN SOURCE JOURNAL). DISTANCE MEASURES WERE APPLIED TO CHARACTERIZE THE STRUCTURE OF THE NETWORK (WHICH JOURNALS ARE CLOSE TO OTHERS IN TERMS OF RECIPROCAL CITATION) IN BOTH 1950 AND 1960. THUMBNAIL SKETCHES OF THE FUNCTIONING OF EACH JOURNAL WITHIN THE NETWORK, IN TERMS OF THESE MEASURES, ARE PRESENTED. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spontaneous Cracking in Unfired Magnesia Compacts Upon Standing in Air

Analytical-grade magnesium oxide powder without binder was compressed hydrostatically to 50,000 lb. per sq. in. to form compacts. When exposed to moist air immediately after pressing, these compacts developed irregularly shaped cracks. Controlled tests, in which these compacts were exposed for various lengths of time to various atmospheres, indicated that in general water vapor, carbon dioxide, and residual stresses had to be present if cracking was to occur. The probable cause of the cracking was the formation of a less dense and mechanically weak basic carbonate of magnesium at crystallite surface points of high stress concentration which developed during the compacting. The adsorption of dry CO₂ at such sites prevented subsequent delayed fracture.     

BLACK-WHITE INCOME INEQUALITY AND THE URBAN SYSTEM OF THE SOUTH

This article reveals the positions of 40 SMSAs in the urban system of the South in 1980, and then investigates whether SMSAs' location in this urban system has an impact on black-white income inequality. The urban sysrem analyzed here is based on Richard Wanner's two-dimensional model and ideas on how each dimension is related to racial income inequality are drawn from work by urban ecologists and radical political economists. It is hypothesized that (1) the higher an SMSA is on the “metropolitan functions” dimension, the more black-white income inequality it will have; and (2) being near the manufacturing end of the “industry structure” dimension has the effect of reducing racial income inequality. Percentage black in the SMSA and black-white educational level are also included in the analysis and the results generally support our hypotheses. The implications of these findings are discussed and the southern urban system in 1980 is compared with ealier depictions of it.     

Thermal Expansion of Orthorhombic PbO

Thermal expansion of orthorhombic PbO was investigated by high-temperature X-ray diffraction. The coefficients in the a ₀, and c ₀ directions are equal and <½ the coefficient in the b ₀ direction. The structure is described in terms of Pb–O chains extended in the a ₀ direction and bonded into layers in the b ₀ direction; appreciable Pb–Pb bonding is indicated. Coordination and bond distances observed in PbSiO₃ and lead silicate glasses, which are similar to those of massicot, and Pb _n O _n polymeric units reported in PbO vapor are interpreted as additional evidence of the importance of PbO chains as structural entities.     

Some Structural and Electrical Properties of Lithium Silicate Glasses

Dielectric measurements, analyzed in terms of the Maxwell-Wagner-Sillars theories of inhomogeneous dielectrics, have been used to investigate the phase-separation characteristics of various lithium silicate glasses. Such measurements are shown to provide evidence of the continuous or discontinuous nature of separated phases and to allow estimates of their shape factors and concentrations. The results indicate that dielectric measurements are particularly useful in following phase-separation processes in glasses from the initial to the final stages.     

Metastable Immiscibility in the B2O3–SiO2 System

Using the phase diagram and a simple solution model, a subliquidus miscibility gap was estimated for the B₂O₃-SiO₂ system. The predicted coexistence boundary, showing a consolute temperature of 520°C, was flat and symmetrical and extended across the complete binary. Gradient furnace heat treatments of selected compositions in this system resulted in phase separation which corresponded closely to the coexistence boundary initially predicted. Calculations and preliminary experimental results indicate that temperatures and compositions exist wherein metastable three-liquid immiscibility occurs in R₂0–B₂0₃-SiO₂systems.     

Systems of Na-Fe-SiO2 Glasses and Steel: I, Wetting and Adherence

Wetting behavior of molten Na₂O-Fe₂O₃-SiO₂ and Na₂O-FeO-SiO₂ glasses on very-low-carbon steel at 900°C in purified Ar was studied. The steel surface was dry-polished and cleaned by ion bombardment. Glass frit was then placed on the metal, and the system was introduced into the furnace without exposure to air. Dynamic advancing and receding contact angles were measured. Shear (push-off) tests were performed on the glass-steel composite at room temperature to determine adherence. The equilibrium contact angles were obtained from the arithmetic mean of the final advancing and receding angles. As the Fe oxide content of the glasses increased, the degree of wetting improved; Fe³⁺ was more effective than a combination of Fe³⁺ and Fe²⁺ in improving the wettability. Glasses very nearly saturated with Fe oxide exhibited high adherence values and chemically adhered to steel.