RESEARCH.
Distinguished group of European visitors discuss new theory on superfluidity of liquid He4, presented before Third International Conference on Low Temperature Physics and Chemistry. Left to right are: L. C. Jackson, University of Bristol (Eng land); C. J. Gorger, Leiden University; Pierre Jacquinot, University of Paris; and A. B. Pippard, Cambridge University. Over 200 scientists from Europe and U. S. attended
Liquid He Obeys Quantum Statistics Lack of λ-point in liquid He 3 suggests Fermi-Dirac statistics, while He 4 seems to follow Bose-Einstein HOUSTON.-Physicists and chemists have now measured t h e heat capacity of liquid H e 3 at temperatures down to 0.5° K., using three different techm^ues. They all agree—no evidence of a λ-point. (Liquid H e 4 has a lambda point near 2° K.) W h a t about nu clear spin disorder at this temperature? W e still don't know, said scientists at tending the Third International Con ference on Low Temperature Physics and Chemistry held a t Rice Institute. Researchers at Los Alamos Scien tific Laboratory calculated liquid heat capacities with t h e Clapeyron equation. For this study, S. G. Sydoriak and T. R. Roberts measured vapor pressures, and ratio of specific heat at saturated vapor pressure to latent heat of vapori zation. Their results, if extrapolated, would indicate t h e entropy is tending toward zero at 0° K. Further work is needed to justify this assumption. Direct measurements were also pre sented during t h e six-day conference sponsored jointly by Rice Institute, Na tional Science Foundation, and the International Union of Pure and Ap plied Physics. An Ohio State group, G. d e Vries and J. G. Daunt, found the liquid heat capacity to increase monotomically in the region of 0.5° to 2° K. Special techniques involved a very small amount of material, equiv 230
alent to approximately 13 cc. of gas. Largest quantity of hquid on record for a study of this kind was reported by Argonne National Lab's D. W. Os borne, B. M. Abraham, and B. Weinstock. Accurate measurements with about 1.7 cc. of liquid—up to one liter of gas—indicated the entropy as ap proximately R In 2. They were able to conclude the possibility of nuclear spin disorder existed. At Duke, this question is being studied by W. M. Fairbank, W . B. Ard, H. G. Dehmelt, and Walter Gordy. Nuclear magnetic resonance techniques should give a direct answer, they say. Although they found spin disorder above 1.2° K., extension of this work to lower temperatures should clarify in ferences made from specific heat data. W e hope to get down below 1° K. very soon, Fairbank says, because we want to find out to what extent the liquid behaves as an ideal Fermi-Dirac gas. If the theory applies, particle spins would be expected to line up antiparallel at sufficiently low temperatures; nuclear magnetic susceptibility would deviate from the classical 1 / T law, and finally become temperature independ ent. Translated, this means spin dis order would no longer exist at very low temperatures. New Theory. Over 200 specialists CHEMICAL
from Europe and the United States spent a lot of time discussing Caltech's R. P. Feynman's new theory on liquid "superfluid" He 4 . H e gave powerful arguments why the quantum statistics of Bose-Einstein are still valid for these helium atoms in the liquid state. Out lining the general aspects, he admits there is still m u c h work to be done in explaining details. Theory postulates (at extremely low temperatures—below 1° K.) that liquid H e 4 has "lazy" vi brational modes of energy, and has the possibility of taking on an excited state with an energy gap between the modes of motion. A better insight to the lambda point phenomenon ma)' soon be obtained. Magnetic Cycling Refrigerator. A new magnetic cycling refrigerator has been developed by C . V. Heer, C. B. Barnes, and J. G. Daunt, Ohio State. Apparatus is capable of maintaining a constant temperature bath of 0.2° K., using iron ammonium alum as the working substance, and lead for the thermal valves. Physicists express the opinion this will be a n important tech nological development for low tempera ture studies below 1° K. For the first time, possibilities are now presented for polarizing atomic nuclei with strong magnetic fields using the refrigerator. William Jiauque was awarded the Nobel prize several years ago for his pioneer work on magnetic cooling. This is the first time a continuous ap paratus for maintaining very low tem peratures has been constructed— Jiauque's equipment worked intermit tently. Nuclear Magnetic Alignment. Brit ish scientists, led by N. Kurti of Oxford University, and Dutch scientists by C. J. Gorter of Leiden University, pre sented papers on their studies of nu clear magnetic alignment. These coun tries are now leading the world in this field of research, conducted in range o£ 0.01° to 0.05° K. Evidence of nuclear alignment, they say, is obtained b y studying radioactive eminations from* atoms such as Co 6 0 and Co 5 8 . Experi ments are now underway on Mn 5 4 Radioactive particles are emitted witbi a preferred direction in space which i s determined by alignment of the n u clear magnetic moment. Studies h a v e already led to some information abou* the excited state of the radioactive n u cleus. Physicists h o p e these studies will give a better understanding o:f nuclear forces. American physicists from Oak Ridge National Laboratory have also b e e n working in this field. L. D. Roberts, S. Bernstein, J. W . T. Dabbs, C, P . Stanford, and T. E. Stephenson r e ported evidence for nuclear magnetic AND
ENGINEERING
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RESEARCH polarization by preferential scattering of a powerful neutron beam coming from t h e Oak Ridge reactor. National Science Foundation. Ray mond Seeger delivered t h e b a n q u e t address, "Research a n d Education," i n order to clarify some policies of t h e National Science Foundation. Explain ing h o w foundation funds are distrib uted among the "various degrees of freedom," h e says they believe every government agency should support basic research. " T h e foundation does not want a 'monopoly' of this business," he states. Foundation is interested i n the spirit under which research is con ducted. T h e idea of doing research behind "academic curtains," that which separates t h e m a t h department from the physics department, and both from engineering, should be discouraged. Foundation wants to invest its dollars in science for science's sake. It has t h e responsibility to see that many differ ent types of institutions receive help. Making contracts is not a purpose of the foundation, it merely wants t o give money to worthy schools for t h e m t o carry out their o w n objectives, n o t t h e foundation's objectives. Schools a r e requested to use that money a s if it belonged to them, a n d not to t h e F e d eral Government.
Idea some schools have that educa tion and research ought to b e separated is not always a good policy, h e feels. T h e research worker can be a better researcher if h e does some teaching because h e comes into contact with t h e greatest unknown—the student's mind. Runyon Fund Ends Y e a r with $1.2 Million in Allocations Damon Runyon Memorial F u n d for Cancer Research closed its fiscal year on Nov. 3 0 with $1,239,357 in alloca tions t o institutions a n d fellowships. For December, t h e fund allocated $29,700 t o four institutions: First Chemical Laboratory, Vienna Univer sity, Austria (15th foreign country re ceiving a D a m o n Runyon F u n d alloca t i o n ) ; Committee for t h e Promotion of Medical Research, N e w York City; Stanford University school of medicine; and George Washington University school of medicine. Infersociety G r o u p to Study Services o f H e a l t h Labs Problems of obtaining adequately trained personnel and raising standards of performance in laboratories related to health will b e studied b y newly
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Throughout 1954, consult your officehandy CMC for quick, accurate answers to raw materials selection, processing or c o m p o u n d i n g p r o b l e m s . Remember, Chemical Materials Catalog is designed by process men for process men.
CHEMICAL
MATERIALS
CATALOG
formed Intersociety Committee on Laboratory Services Related to Health. By coordinating activities of various in terested societies, group hopes t o avoid difficulties confronting individual or ganizations trying t o solve such prob lems. G r o u p h a s these specific objectives: to define l a b practice a s related to health, to recommend standard quali fications for personnel, t o cooperate with educational institutions i n devel oping curricula, to encourage profes sional certification i n scientific special ties practiced, and to promote desirable patterns of approval of labs. Organizations participating a r e : N a tional Association of Clinical Labora tories, American Public H e a l t h Asso ciation, Society of American Bacteri ologists, American Association of Clin ical
Chemists,
AMERICAN
CHEMICAL
SOCIETY, American Society of Bio logical Chemists, and American Society of Professional Biologists. •
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^ Association of American S o a p a n d G l y c e r i n e P r o d u c e r s establishes a fel lowship for research on fatty acids d e rived from domestic fats a n d oils. Study, a t USDA's Eastern Regional Re search Laboratory in Philadelphia, will b e directed particularly towards broad ening industrial application of t h e acids. Fellowship, which provides for a senior a n d junior fellow, extends for o n e y e a r a n d m a y b e renewed b y mutual agreement. ^ Elmer P e t e r Kohler Fellowship a p plications are being accepted b y Chair m a n of t h e Chemistry Department, H a r v a r d University, Cambridge 3 8 , Mass. Candidates wishing t o study elsewhere t h a n a t Harvard will b e con sidered, b u t preference will b e given to students w h o either have studied or p l a n to study at Harvard, Radcliffe, or Bryn Mawr College, t h e institutions at which Kohler taught. Nominations a r e d u e by F e b . 8, 1954. ^ An i n d u s t r y fellowship for r e s e a r c h o n cotton t e x t i l e s has b e e n established b y National Canvas Goods Manufac turers Association at USDA's Southern Regional Research Laboratory i n N e w Orleans. Purpose is to improve t h e performance of canvas goods a n d sew ing thread i n awnings, tents, a n d tar paulins. Association h a s appointed John V. Bailey, formerly of University of Wichita, to conduct the work of t h e fellowship.
REINH0LD PUBLISHING CORPORATION p* Research Corp. grants $1800 t o Benson R. Sundheim, N e w York Uni versity, to study radial distribution function in binary liquid mixtures.
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