Search

The viscous flow behavior of a 9.6-kg lunar rock containing 22.5 wt.% FeO was studied in the temperature ranges from 620 to 700 C and from 1215 to 1400 C. The material was synthesized under mildy reducing conditions to simulate the Fe(2+)/total Fe ratio of the lunar environment. The effect of iron oxidation state on flow behavior in the high viscosity region is studied for specimens of the 15555 composition with Fe(2+) concentration ratios of 0.94, 0.76, and 0.20. A change in ratio from 0.94 to 0.76 had no observable effect on viscosity, whereas a change from 0.76 to 0.20 was accompanied by a drastic increase in viscosity (some three orders of magnitude) at a given temperature, but without changing the form of the variation of viscosity with temperature. The flow behavior is analyzed as a function of the structural features of the glasses.

The viscosity of 99.99% pure selenium has been determined over the available range of temperature where crystallization could be avoided. A bending beam viscosimeter was used to obtain data in the high viscosity region, and a rotating cylinder instrument was employed for the low viscosity range. Also determined was the stress dependence of the viscosity at temperatures of 31.5 and 29.6°C. The critical stress for non-Newtonian flow was found to lie in the range of hundreds of psi, which is appreciably smaller than that for oxide liquids in a similar range of viscosity.

Summary Microelectrode studies of human lymphocytes after 24 to 48 hr of stimulation by phytohemagglutinin are described. A stable transmembrane potential of about -18 mV was detected. The input resistance of these cells was about 5 megohms. Clumps of stimulated cells exhibit junctional communication as revealed by coupling coefficients of 0.2 to 0.6. No changes in membrane properties and intercellular communication were detected throughout the observed period. The results reported here suggest that the establishment of interlymphocyte communication is possibly involved in the control of mitosis.

High‐temperature viscous flow data are reported for three relatively simple organic liquids: o‐terphenyl, salol, and α‐phenyl‐o‐cresol. The results are combined with previous flow data on the same liquids to obtain viscosity‐temperature relations over some 15 orders of magnitude. For each liquid, as well as for tri‐α‐naphthylbenzene, the free‐volume theory of Turnbull and Cohen is found to provide a close representation of the data for viscosities between 10−2 P (the high‐temperature limit of the data) and about 104 P. Over this range, even the pre‐exponential factors derived from fitting the experimental results are in close agreement with those predicted by the theory. At lower temperatures, the free‐volume expression overestimates the difficulty of flow. For all four organic liquids, the fractional free volumes at the points of departure, TB, of the experimental data from the free volume predictions are close to 0.015. An empirical high‐temperature flow relation of the free‐volume form is suggested as ...

The viscosity of liquid anorthite has been determined over the temperature ranges between 1450 to 1620 C and 820 to 950 C. The high-temperature data agree well with previous experimental data and with predictions of the Bottinga and Weill model. The overall log (viscosity) versus 1/T relation exhibits pronounced and rather continuous curvature. The viscosity of anorthite is higher at any given temperature and more strongly temperature-dependent than that of the anorthite-rich lunar compositions 14259, 14310, and 15418. The room-temperature density of glassy anorthite (2.64 gm/cu cm) and the thermal expansion coefficients of glassy and liquid anorthite have also been determined. The volume expansion coefficient for the glass is about 0.000018 per deg C, and that for the liquid is about 0.000048 per deg C. These values are used to relate the high-temperature flow data to the predictions of free-volume theories.

Karl Brunner's interest in rules for monetary policy is well-known. Since the Federal Reserve would not follow pre-announced rules and Congress did not require them to do so, Brunner (1977) supported the efforts of Robert Weintraub and others to require the Federal Reserve to announce targets for monetary growth.1 He testified in favor of targets after Congress approved Congressional Resolution 133. This resolution required the Federal Reserve to provide the public and Congress with more precise information about the monetary actions that they contemplated. The announcements have not proven to be reliable guides to actual money growth. Should they be abandoned?

Hydron, a hydrophilic polymeric hydrogel, has been shown to absorb and elute fluorouracil at predetermined rates in vitro. Fluorouracil-charged Hydron pledgets were found to significantly suppress Ehrlich's ascites tumor in CF1mice compared with controls receiving nonmedicated implants of polymer. An implantable chamber was designed to provide sustained selective release of fluorouracil. Preliminary studies showed the unit was able to deliver high concentrations of the antitumor agent locally while completely sparing tissues remote from the implant site.