I&EC TRENDS TODAY Improvements in the measurement of viscosity of molten glasses are the result of a new study by A. Napolitano, P. B. Macedo, and E. G. Hawkins of the NBS Institute for Materials Research. By using a special rotating-cylinder viscometer, the investigators have extended the range of accurate viscosity data to 10" poises. I n conjunction with this work, the viscosity of dehydrated boron trioxide glass was determined from 318' to 1403" C. Data for this high-purity single-component glass should prove valuable for other investigators in the glass industry. The viscometer had previously been operated only in two modes that permitted viscosity measurements from 1 to 707 poises. Although the third mode ("driving" mode) was intended only to extend accurate measurements beyond 1 0 7 poises, its useful range is from TO6 to 701° poises. In the driving mode, a known torque is applied to the spindle while the cup is held at rest. W i t h a sensitive optical system, the angular velocity of the spindle is measured to give viscosity.
permits those with no experience or proximity to a computer to program via the written word. Compiled by J . Hilsendrath, G. G. Ziegler, C. G. Messina, P. J . Walsh, and R. J . Herbold, O M N I T A B is explained in NBS Handbook 7 0 1 which is available from the Government Printing Ofice. O M N I T A B is a completely assembled interpretive program for the IBM 7090/7094 which permits direct use of the computer without a knowledge of programming. Instructions are given in the form of ordinary English sentences built from the basic command list contained in the handbook. Since only the j r s t six characters of the sentence are crucial in the computer operation, the remainder of the characters in the sentence are used only for the benejt of the ((programmer.)' The OMNITAB computer program for statistical and numerical analysis
The chromatofuge-a
marriage between chromatography and centrifugation-
promises to broaden the range of ion exchange chromatography. The device increases the number of regeneration-washing-synthesis cycles per unit time and avoids dilution of the end product. The new method has been patented in the Soviet Union by V. V. Krokhv and represents a considerable improvement in the synthesis of compounds via ion exchange. Synthesis in chromatographic columns requires much time for the passage of the solutions through the resin beds, and even more for regeneration. The device, successfully used to synthesize tetraethylammonium iodide, bromide, and hydroxide, consists of a cylindrical resin bed which rotates up to 800 r.p.m., with feed introduced through a perforated tube at the axis and products removed through the perforated wall of the cylinder. Although not mentioned by the author, it would seem possible to program the regeneration-washiag-synthesis cycle to make the unit completely automatic. The first direct measurement of the minimum energy required for a chemical reaction has been made at the California Institute of Technology by a group headed by
Dr. Aron Kuppermann, Professor of Chemical Physics.
The key measurement shows that 0.33 electron volt is required to initiate the splitting of a hydrogen molecule and linking a deuterium atom with one of the hydrogens. The reaction was energized by a monochromatic light from a 200-watt mercury bulb. The reaction was initiated when the light beam was shone upon a glass reaction vessel containing a mixture of two gases, hydrogen and deuterium iodide. As the gases were irradiated, their chemical composition gradually changed. A t the end of an hour or more, the contents of the vessel were examined in a mass spectrometer. The experiment was then repeated with light of increasing wave length until deuterium hydride was formed. This furnished directly the minimum energy required for the reaction to occur. VOL. 5 8
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