Film thickness in horizontal annular flow

Film thickness in horizontal annular flow in small diameter pipes (8-12 mm) was measured as a function of circumferential position. In addition a simple analytical model for the prediction of the film thickness at the top and bottom of the pipe is proposed.     

Contact hypothesis in ethnic relations.

Reviews research regarding the effects of intergroup contact on ethnic relations. The investigations discussed include both intra- and cross-cultural studies involving contact between various ethnic groups. The principles and generalizations emerging from these studies are categorized under (1) opportunities for contact, (2) the principle of equal status, (3) contact with high-status representatives of a minority group, (4) cooperative and competitive factors, (5) casual vs. intimate contact, (6) institutional support, (7) personality factors, and (8) direction and intensity of initial attitude. The major generalization derived from the present review is that changes in ethnic relations do occur following intergroup contact, but the nature of this change is not necessarily in the anticipated direction; "favorable" conditions do tend to reduce prejudice, but "unfavorable" conditions may increase intergroup tension and prejudice. Ethnic attitudes may also change in their intensity, and they may be limited to specific areas of the ethnic attitude and not be generalized to other aspects of the intergroup relationships. Some practical applications are also considered. (2 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simple test for differentiation between E. coli and A. aerogenes

An important problem in water quality control is the ability to differentiate between E. coli (faecal) and A. aerogenes (non-faecal) coliforms. To perform this differentiation, a simple test, based on a modification of the selective mFC medium and optimal incubation temperature (37°C) is proposed. Under these specific conditions E. coli bacteria develop into dark blue colonies, whereas A. aerogenes into pink ones. The intermediate coliform bacteria appear greenish-blue or pink, depending on their relation (closeness) to E. coli or A. aerogenes.     

Data management for an interactive graphics system oriented to planning applications

INTRANS is a man-computer interactive graphics system, intended for analysis of urban and transportation planning problems. It is designed to operate primarily under time sharing on IBM 360/370 computers. The paper describes the functional design and the structure of the data management of INTRANS.

The data management is designed to answer the specific needs of planning applications: large data-sets, comparative analysis of several alternatives, and interface with batch processing computer programs. At the same time, the system is designed to operate within an environment of extremely limited resources of core and computing time.     

Polydepsipeptides I. Synthesis and Characterization of Copolymers of α-Amino and α-Hydroxy Acids

Copolymers of the type were synthesized and characterized. The syntheses of these copolymers were achieved by copolymerization of an α-amino acid N-carboxy anhydride and an α-hydroxy acid anhydrosulfite in the presence of a catalyst. The copolymers were characterized by spectroscopic methods including infrared, circular dichroism and nuclear magnetic resonance. Specific cleavage of the ester bonds by hydroxylamine in the cold confirmed the A-B block structure where the A represents the poly(amino acid) segment and the B indicates the polyester segment. Measurements by nmr and viscosity indicate that the blocks consist of short chain lengths.     

Bacteriophages as viral pollution indicators

f2 Phage, attenuated Polio I (LSC) strain introduced daily to a 350 l. experimental oxidation pond showed no decrease in bacterial viruses f2 or other coliphages or Polio I strain.Ratios of coliphages to human enteric viruses ranged in flood waters from concentrations as low as 1:1 to as high as 10³:1; in wastewater at various seasons the ratio was 10⁵:1; in trickling filter effluents in winter it was 10⁴:1; in spring 10⁵:1, in summer and fall 10⁴:1, in oxidation pond effluents in winter 10³:1; in spring 10⁴:1; and in summer and fall 10³:1. Out of three epidemics in small communities caused by failure of water supply, coliphages were found to be positive. At the same time only two samples of human enteric viruses were positive (the third was contaminated with yeasts).Chlorination experiments using the experimental oxidation pond showed that f2 was most resistant, MS₂ was very resistant, and coliphages were more resistant than attenuated Polio I virus. Experiments with the oxidation pond effluents showed that coliphages were at least as or even more resistant to chlorine than human enteric viruses.     

Absorption of a multicomponenet gaseous mixtures in the presence of instantaneous surface reaction

The rate of absorption from a multicomponent gaseous mixture into a flowing stream in the presence of instantaneous surface reaction is investigated. This is effected by using the generalized Fick's Law for multicomponent diffusion and also by applying the approximate approach based on the assumption that the concentrations of the reactive species are small. Constant properties are assumed for the mixture which are taken at a reference state. As an example, the absorption of C0₂-H₂S and C0₂-H₂ from air are considered. The results show that when the binary diffusion coefficients of the species in the inert gas are greatly different, the error introduced in calculations based on the “Low Concentration” approach is quite appreciable.     

Introduction of Formal Reliability Engineering in Israel

During my sabbatical leave in Israel, I approached reliability engineering in a number of ways. The papers I delivered in conferences, lectures, workshops, short courses, in-plant training, and indoctrination in reliability engineering appreciably increased interest in the reliability discipline. Engineers in Israel for the first time took the 1981 American Society for Quality Control (ASQC) examination for ASQC certification as reliability engineers. The results of the 1981 April examination were gratifying: 11 passed the examination and were awarded the CRE (ASQCCertified Reliability Engineer).