Classified abstracts 717-733 20 717. Preliminary
design development
of a vacuum
chamber
for the
Argonne ZGS. (USA) The development of one possible design for a new vacuum chamber for the Argonne Zero Gradient Synchroton is reported with the following features: withstanding full atmospheric load without suffering permanent deformation, operating in a region of high radiation without loss of vacuum or structural integrity, and operating in a pulsing magnetic field with a minimum of eddy current effects. G M Lee et al, Midwestern Universities Research Association, Stoughton, Wisconsin, March 1965, IOpages. LU
718. A scattering chamber for charged particle work.
(Netherlands) designed for experiments using offers a great flexibility in the of a vacuum ion pump greatly onto targets during the experi-
This scattering chamber has been primarily solid state detectors. It arrangement of counters. The use reduces the deposition of impurities ment. (USA) R W Zurmuehle, Nucl Instrum Methods, 36, Sept 1965,168-l
72.
20 (USA) 719. An unconventional ultrahigh-vacuum facility. A vacuum system was developed which is capable of maintaining a pressure of lo-r0 torr in the interaction region during measurements of atomic collision cross sections. The performance of two pumps is compared. The compartmentalization vessel is described and the procedure for obtaining the required vacuum is given. C F Bamett and J A Ray, Oak Ridge National Laboratory, Symposium on Engineering Problems of Controlled Thermonuclear Research, Livermore. Calif 20 : 33 720. Maintenance of high-vacuum conditions for rocket testing. (USA) The cryopump, which provides high mass flows at low pressure, is considered as a technique to provide the high pumping speeds required for testing rocket motors. Some of the difficulties involved in cryopump design are discussed, and formulas for solving for various conditions are introduced. R L Chuan and D A Wallace. Sixth Annual Svmoosium on Soace Environmental Simulation, St Louis, Missouri, May 1965.16pages. 20 : 33 721. The Stanford two-mile linear accelerator vacuum system. (USA) The vacuum system of the Stanford two-mile linac has been designed as nominally a very high vacuum system operating in the 1Om6to 1OF torr region. Main vacuum pumps are of the getter-ion type; the pumps are connected to an all-metal system fabricated of stainless steel except for Viton O-rings in the valve seats. A brief description of the vacuum system for the beam switchyard at the end of the accelerator is included, since it is an integral part of the system. S R Conviser, IEEE Trans Nucl Sci, NS-12, (3). June 1965,699-704. 20 : 49 722. Determination of elevated-temperature fatigue data on refractory alloys in ultrahigh vacuum.
(USA)
Description of vacuum fatigue test chambers. C R Honeycutt et al, Quarterly Report, Thompson Ramo Wooldridge Inv, Cleveland, Ohio, Jan-April, 1965,19pages. 20 : 33 723. Precision (O.l”C) vacuum cryostat and furnace for Mossbauer experiments. (Great Britain) The design of a small vacuum cryostat and furnace for a Mossbauer spectrometer is described. A regulating system for a O.l”C temperature stability for periods of several days is given. (Netherlands) F van der Woude and G Boom, Rev Sci Instrum 36,1965,800. 20 : 32 724. Design concepts for modem accelerator vacuum systems-predictions versus experimental data.
(USA)
Design parameters for accelerator vacuum systems are studied with reference to the requirements which appear in modern strongfocussing machines. The two major problems considered are restrictions in both pumpdown time and system base pressure created by trends towards very small apertures. Basic kinetic equations are used in a method of estimating performance. Influence of various pumping systems on prediction is discussed and design recommendations are offered. F S Reinath and D T Scalise, Lawrence Radiation Laboratory, Berkeley, Calif, March 1965, Ilpages.
20 : 25 : 32 725. Accelerator vacuum problems: in-line oil-trapping between the I USA) Stanford linear accelerator and the beam switchyard.
The thirty accelerator sectors (each 333 ft -long) of the’ two-mile machine will be evacuated with sputter-ion pumps to pressures low enough to limit rf breakdown and multifactor problems. Description of the pumps and traps used is given. E L Hoyt and E L Garwin, IEEE Trans Nucl Sci, NS-12, (3). June 1965, 740. 20 : 28 (USA) 726. Vacuum ovens and furnaces. Reviews the ovens and furnaces used and the particular advantages of each for different processes. W R Jones, Semiconductor Products and Solid State Tech, 8 (12), 1965,47. 20 727. Equipment for measuring the electric conductivity of semiconductor materials in liquid and solid states.
(USSR)
Description of a high temperature vacuum furnace for the synthesis of semiconductor materials of controllable composition in vacuum or at high pressure in an atmosphere of inert gas at temperatures up to 1700°C. The furnace uses a simple and compact radio circuit for non-contact measurement of the electrical conductivity of solid or molten materials during the process. E N Nikitin and V K Zaitsev, Pribory i Tekh Eksper, IO, 1965, 203205, (in Russian). 20 : 34 728. Rotating arm apparatus in Japanese National Aerospace Laboratory. (Japan) Description of a rotating arm apparatus at the National Aerospace Laboratory in Japan. The vacuum chamber of the device is 20 cm in height and 175 cm in diameter. The arm is 80 cm long and the maximum speed of the model mounted on the tip of the arm is about 500 m/set. The highest vacuum attainable is 2 x lo-& torr. The apparatus is intended for pressure distribution measurement and heat-transfer measurement from slip flow to free molecule flow. Anon, J Jap Sov Aeronaut and Space Sci, 13, Aug 2965, 273-274, (in Japanese). 20 : 34 729. A large ultrahigh-vacuum environmental chamber with liquid (USA) helium cooled liner. C D Elderkin and J M Bradford, J Environmental Sciences, 8 (6),
Dee 1965,11-15. 20 730. The history
and
development
of furnace
vacuum
degassing.
(USA)
Although vacuum equipment had been installed and used for many years at the Bethlehem Plant, an increased demand for degassed steels necessitated a review of the vacuum installation. The outcome of the analysis was a furnace vacuum degassing unit which is a useful tool for vacuum treating normal electric furnace grades produced by the 2-slag process. A L Lehman, Iron and Steel Eng, 43 (II), Jan 1966, 75-84. 20 731. An improved strip-sealed continuous rotation scattering chamber. (Netherlands) An improved design of an evacuated chamber is described having two ports in a horizontal plane. The angle between ports can be changed continuously through an angular range of 180” from - 10” to + 170” without disturbing the high vacuum maintained inside. R A Hawrylak et al, Nucl Instrum Methods, 36,Oct 1965,237-240. 20 732. A laboratory lined vacuum arc furnace.
(USSR)
Vacuum arc furnace discharging metal without interrupting the arc by means of pivoting furnace housing or with interruptions of the arc by pivoting a single crucible. A M Khromov et al, Electrotermiya Nauk Tekn, 42,1965, 30-32, (in Russian).
21. Pumps and pump fluids 21 733. Device for continuous pumping and measuring of small quantities of gases.
(Czechoslovakia)
The apparatus is a combination
of a Hg vapour diffusion pump and 273