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Infrared and Raman spectra have been measured of scheelites with formula ALnW8O8, ALnMo2O8(A = Li, Na, K; Ln = La, Y), Y2MWO8M = Ge, Si), Y2GeMoO8and the zircon Y2SiMoO8in order to get information about the crystallographic order. The A+and Ln3+ions in the scheelites ALnW2O8and ALnMo2O8are probably ordered in layers Ln-Ln-A-A perpendicular to the c-axis. The order is short-range only. The degree of order decreases in the sequence K, Na, Li. The compounds Y2MWO8and Y2GeMoO8are not ordered, whereas the Si4+and Mo6+ions in Y2SiMoO8are ordered in alternate layers perpendicular to the c-axis. The use of vibrational spectra for the determination of crystallographic order is discussed.

The chemical manifestations of discrimination in long-range (non- contact) interactions of chiral molecules are analysed in three stages. A simple thermodynamic model is used to establish a method of presenting experimental data (such as differences in racemization rates, solubilities and redox potentials of pure enantiomers in non- associating chiral media) in terms of well defined thermodynamic discriminations. The thermodynamic quantities are then related directly to discriminations in intermolecular interactions through a statistical thermodynamic treatment. Estimates of the discrimination in intermolecular forces from experimental thermodynamic data suggest that only electrostatic interactions are sufficiently large to account for the experimentally observed values of the discrimination.

It has been observed experimentally that circular dichroism bands can appear at absorption frequencies of achiral molecules when chiral species (which do not associate with the achiral molecules) are added to the solution. This paper treats those contributions to the induced activity in the achiral species which are the results of van der Waals coupling to the chiral species. Use of perturbation theory leads to the expression of the induced rotatory strength as a series in 1/r, r being used in a general sense as the effective achiral-chiral molecule separation. Averaging over all orientations of each molecule yields non-vanishing terms falling off as 1/r6. The results suggest that the effect may be important even in completely dissociated systems.

A theory is presented for the treatment of surface states in general molecular crystals. The perfect and surface crystal solutions are developed in terms of a common basis exploiting the common translational symmetry of all planes parallel to the crystal surface. The surface states are then determined in terms of the perfect crystal solutions using Greens' function methods. The theory is applied to the determination of the conditions under which localized surface states appear in crystals with one molecule per unitcell.

A complete description of the “Constant temperature arc” method of quantitative analysis which has been developed in Eindhoven is given, with tables of the empirically determined K-values announced so that they can be checked in other laboratories. The method consists of completely volatilizing 5 mg of a powdered sample in a shallow anodic crater of a carbon arc, with the addition of materials to modify the rate of volatilization if required. The line intensities are calibrated by comparison with selected Fe-lines so as to get comparable analytical results; the calculations required are illustrated by several examples which also indicate the accuracy of the method.

A complete description of the constant temperature arcmethod of quantitative analysis which has been developed in Eindhoven is given, with tables of the empirically determined K-values reported so that they can be checked in other laboratories. The method consists of completely volatilizing 5 mg. of a powdered sample in a shallow anodic crater of a carbon arc, with the addition of materials to modify the rate of volatilization if required. The line intensities are calibrated and corrections are made by comparison with selected Fe lines, originating from a “standard light source” so as to get comparable analytical results; the calculations required are illustrated by several examples, which indicate the relative accuracy of the method to be approximately 10%.

Separate groups of Ss were trained in multiple probability-learning situations where sets of probabilities were (a) .10, .20, .30, .40, .50, (b) .50, .60, .70, .80, .90, and (c) .10, .30, .50, .70, .90, respectively. Subsequent to the training session Ss received test trials on all combinations of the five probabilities. Differential training with equal probabilities in different contexts gave different learning curves. Ss' uses of these probabilities in the test situations also varied as a function of prior training.

This paper examines theoretically the effects of strain on the exciton properties of some molecular crystals. It is found that the parameters of exciton theory are relatively sensitive to changes in lattice parameters of the crystal, and thus strain can result in significant changes in the crystal spectrum. The method proceeds through strain derivatives of the exciton parameters, which are evaluated for the unstressed crystal geometries. In this way, the influence of pressure and temperature on the spectrum is examined. The strain derivatives are evaluated for anthracene and naphthalene for light incident on the ab-face, and the theory used to re-examine some of the features of the first singlet of anthracene. Good agreement with experiment is obtained.

Antibiotic sensitivity tests to determine the minimal inhibitory concentrations (MIC) and the minimal lethal concentrations (MLC) for six antibiotics were conducted against mastitic isolates of staphylococci in skim milk and broth. The MIC and the MLC for all the antibiotics except benzylpenicillin were considerably higher in skim milk than in broth. Benzylpenicillin was the most effective antibiotic tested in either medium, and dihydrostreptomycin was the least effective against the organisms tested.

College students were preselected on the personality variables need Achievement (nAch) and manifest anxiety (Anx) to form a 3 by 3 factorial arrangement and to relate these measures to probability-learning, decisionmaking, and risk-taking behaviors. After receiving 90 training trials on each of three green lights which had probabilities of 1/6, 1/2, and 5/6 of being followed by a red event light (probability-learning), Ss were asked to make decisions about the predictive reliabilities of these lights when they occurred in combinations or singly, while the red light was covered (decision-making). Ss were then given a zero expected value gambling game and a double-or-nothing final bet. Neither personality variable showed a consistent relationship to probability-learning, decision-making, or risk-taking behavior according to various criteria.

Zusammenfassung 1.Die Untersuchungen an Patienten mit Carcinom, Hypertonie, Lungentuberkulose, Nieren- und Schilddrüsenerkrankungen haben gezeigt, daß die insulinzerstörende Kraft des Blutes dieser Kranken hinsichtlich der Intensität von der insulinzerstörenden Kraft des Blutes gesunder Menschen nicht nennenswert abweicht.2.Die Untersuchungen an 6 Kranken mit Lebercirrhose ergaben im Auftreten des Insulinzerstörungseffektes eine Abweichung von der Norm; bei diesen Kranken wurde eine Verzögerung im Auftreten des Insulinzerstörungseffektes beobachtet, welche besonders deutlich in der Altersstufe über 60 Jahre in Erscheinung tritt. Diese Beobachtung könnte für eine wesentliche Abschwächung der insulinzerstörenden Kraft des Blutes beim Krankheitsbild der Lebercirrhose sprechen.3.Die Notwendigkeit weiterer systematischer Untersuchungen der IZK des Blutes beim Krankheitsbild der Lebercirrhose wird begründet, da durch Bestätigung dieser Befunde ein Weg eröffnet würde, weitere wichtige Erkenntnisse über das Wesen der insulinzerstörenden Kraft des Blutes zu schaffen.

The effectiveness of two methods for the isolation of bacteria from raw milk was investigated. Raw milk from normal udders was subjected to the direct membrane filtration technique and the 18-hr incubation technique. The results indicate that the membrane filtration technique gives a more complete picture of the flora of a normal udder than does the 18-hr incubation technique. Use of various methods for the isolation of organisms from milk samples may account for the extensive disagreement on the presence and types of organisms associated with normal and mastitic udders.

The bacteriostatic effects of sulphathiazole, sulphapyridine, sulphamerazine and sulphadimidine were studied on seven mastitic and eight non-mastitic Staphylococcus albusorganisms. Sulphathiazole in trypticase soy broth (TSB) was the most effective, followed by sulphapyridine, sulphamerazine and sulphadimidine, in that order. With non-fat milk (milk media) the same order of antibacterial activity was found.