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1174. Reduced pressure system, protected against entry of air
Classified
abstracts
1168-1181
21 1168. Pumping speed of the turbo-molecular pump as function of the molecular weight. (Germany) Experiments with gases of different molecular weight have revealed that the pumping speed of the turbo-molecular pump decreases when the molecular weight rises. The reciprocal value of the pumping speed depends geometrically on the square root of the molecular weight. K Petzold and H Blank, Vukurrm-Technik, 15 (3), 1966,61, (in German). 21
1169. Impeller pumps. S Lazarkiewicz and A T Troskolanski, Yergumorr Z+eus (OxJi&), 1965, 648 pages, 120s. 21
1170. Considerations in the measurement of cryopumping capture coefficients. (USA) A survey is presented of the more important theoretical and practical relationships involved in the study of cryopumping. Starting with a rigorous definition of the capture coefficient, the effects of temperature on the measured values are derived. Several practical points in the design of a chamber for cryopumping measurements are given, including gauge placement, calibration, effect of outgassing and temperature measurements. J D Haygood and J P Dawson, Rep AEDC-TR-65-6#, AD-461132, .4pril I965, (Arnold Eng Develop Center, Tenrz). 21 1171. The maintenance of high vacuum conditions for rocket testing. (USA) The cryopump, which provides high mass flow at low pressures, 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 in various conditions are introduced. Also illustrated are the probability of both wall collision and direct back-reflectance for direct flow in tubular elements. R L Chuan and D A Wallace, 6tl1 Amr Symp ori Space Enrironme~~tal Simulation, 17-18 Center, Teun).
May
1965,
(Arnold
Engineering
Development
22. Gauges 22 : 15
New method of measuring the flow rates of hot and contaminated gases and the degree of vacuum in these. See abstract number 1128.
24. Valves 24 1172. Apparatus for prevention of gas leaks from equipment. (USSR) A N Brushtein. Vestn Tekhn i Ekon Injxw, 7, 1965, 25, (in Russian).
24 1176. Fast-acting ribbon-type electrodynamic valve.
A new fast-acting ribbon-type electrodynamic valve for admitting small quantities of gas to an evacuated chamber is described. Distinctive features include a rubber or similar valve seat reinforced by plastic material on the shutter side, and a shut-off device made in the form of a metal strip or ribbon encompassing the seat; sockets at the ends regulate the tension in the ribbon, and contacts are provided for connection to the condenser battery which operates the valve. In order to protect the ribbon from rupture, a ring-shaped metal support is provided, and in order to accelerate the return of the ribbon to its original position an additional condenser-battery circuit is arranged to create an appropriate electrodynamic force between the ribbon and its support. N V Filllpov, Author’s Certificate, USSR, class 47g, 2I/lO (F 06k), No 173555, claimed 22/l/62,
25. Baffles,
traps
published
and refrigeration
21916.5, (in Russian).
equipment 25
III. Vacuum
Applications
30. Evaporation
and sputtering 30
24
1174. Reduced pressure system, protected against entry of air. A vacuum system is described, which is fitted with a safety valve with a predetermined shut-off device, which automatically closes whenever air enters the outer end of the container. The outer container is made of a series of 4-6 separate cylindrical vessels, interconnected by means of conical constrictions which reduce the flow of gases so that a robust safety valve with a shut-off time of several 100 set, is adequate to avoid leakage of air into the system. R Jean, (CSF-Compagnie Generale Sam File), German Patent (Cl. B OIj), 3 Feb 1966; French Patent
appl3
May
1962, 24
1175. Valves.
(USSR)
1965, 860, (in Russian). 30 1178. The deposition of silicon upon sapphire substrates.
A technique was developed for depositing silicon on single-crystal sapphire substrates composition of SiH,/Hz mixtures. Electron Laue reflection examinations of these films patterns. P H Robinson and C W Mueller, Trans Me/ail
single crystal films of via the pyrolytic dediffraction and X-ray revealed single crystal Sot oj’ AIME,
30
from PriborJJ i Tekh Eksper,
2 Feb 1966, German Appl23
408
236 (3),
Observations of calibrated epitaxial nickel films on (111) copper. (Netherlands) Nickel was evaporated in high vacuum from a calibrated source, one monolayer at a time, on a clean (111) copper single crystal substrate. Excellent order in arrangement of condensed nickel atoms with the same orientation as the substrate, but with the lattice spacing of Ni, was observed when the substrate was maintained at about 200°C during evaporation. Each successive monolayer grew epitaxially with respect to these layers immediately below it, always with the lattice spacing of nickel. C A Haque and H E Farnsworth, SItrfbce Science, 4 (2), 1966, 195-200. 30 1180. Carbide coatings on carbon resistors to prevent vaporization. (USA) Carbon resistors of any shape are heated to 2000-2300’ by electric resistance or induction in a vacuum of about 10m5mm while exposed to vapour arising from a melt of a metal forming a very refractory carbide. H R Smith, Jr, (Temesral Metallurgical Corp), US Patent 3,230,110, (Cl I I7-228),
1965).
(USA)
1966,268-274.
A glandless vacuum gate valve with a conditional flow-passage diameter of 300 mm is described. Its kinematic circuit and a diagram of its operation are given. A I Pipko et al, Instrum and Exper Tech, Dee 1965, 713, (Trurrsluted 3, May/June
: 20
Development tendencies of high-vacuum engineering. Part I. See abstract number 115 1. 30 : 20 Development tendencies of high-vacuum engineering. Part II. See abstract number 1152. 30 1177. Oriented growth of oxide lilms on beryllium. (USSR) The beryllium specimens were prepared by vacuum-melting and by hot-pressing. The dependence of oxide film growth on temperature is discussed. L D Kolomiets and V K Khorenko, Fiz Metal i Mefalloved, 20 (6),
1179.
(Great Brifain)
The valve allows periodic samples to be taken from a number of chambers through each of which gas is flowing. Two small-bore rubber tubes lead to the atmosphere and gas analyzer, respectively. J B Watkins and B C Peacock, Lab Practice, 14 (II), 1965, 1295.
1,210,004, 3 pages.
: 17
Cryogenic instrumentation. II. Sensing flow and composition. See abstract number 1138.
24 1173. An electrically-operated two-way gas valve.
(USSR)
18 Jan 1966, Appl22
Jan 1962: 4 pages. 30
1181. Vapour deposition of semiconductor materials. (Greaf Brifain) Anon, Siemens and Halske AG, Brirish Patent 1,019,080, (Cl C 23c), Aug 1962; 7pages
abstracts
1168-1181
21 1168. Pumping speed of the turbo-molecular pump as function of the molecular weight. (Germany) Experiments with gases of different molecular weight have revealed that the pumping speed of the turbo-molecular pump decreases when the molecular weight rises. The reciprocal value of the pumping speed depends geometrically on the square root of the molecular weight. K Petzold and H Blank, Vukurrm-Technik, 15 (3), 1966,61, (in German). 21
1169. Impeller pumps. S Lazarkiewicz and A T Troskolanski, Yergumorr Z+eus (OxJi&), 1965, 648 pages, 120s. 21
1170. Considerations in the measurement of cryopumping capture coefficients. (USA) A survey is presented of the more important theoretical and practical relationships involved in the study of cryopumping. Starting with a rigorous definition of the capture coefficient, the effects of temperature on the measured values are derived. Several practical points in the design of a chamber for cryopumping measurements are given, including gauge placement, calibration, effect of outgassing and temperature measurements. J D Haygood and J P Dawson, Rep AEDC-TR-65-6#, AD-461132, .4pril I965, (Arnold Eng Develop Center, Tenrz). 21 1171. The maintenance of high vacuum conditions for rocket testing. (USA) The cryopump, which provides high mass flow at low pressures, 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 in various conditions are introduced. Also illustrated are the probability of both wall collision and direct back-reflectance for direct flow in tubular elements. R L Chuan and D A Wallace, 6tl1 Amr Symp ori Space Enrironme~~tal Simulation, 17-18 Center, Teun).
May
1965,
(Arnold
Engineering
Development
22. Gauges 22 : 15
New method of measuring the flow rates of hot and contaminated gases and the degree of vacuum in these. See abstract number 1128.
24. Valves 24 1172. Apparatus for prevention of gas leaks from equipment. (USSR) A N Brushtein. Vestn Tekhn i Ekon Injxw, 7, 1965, 25, (in Russian).
24 1176. Fast-acting ribbon-type electrodynamic valve.
A new fast-acting ribbon-type electrodynamic valve for admitting small quantities of gas to an evacuated chamber is described. Distinctive features include a rubber or similar valve seat reinforced by plastic material on the shutter side, and a shut-off device made in the form of a metal strip or ribbon encompassing the seat; sockets at the ends regulate the tension in the ribbon, and contacts are provided for connection to the condenser battery which operates the valve. In order to protect the ribbon from rupture, a ring-shaped metal support is provided, and in order to accelerate the return of the ribbon to its original position an additional condenser-battery circuit is arranged to create an appropriate electrodynamic force between the ribbon and its support. N V Filllpov, Author’s Certificate, USSR, class 47g, 2I/lO (F 06k), No 173555, claimed 22/l/62,
25. Baffles,
traps
published
and refrigeration
21916.5, (in Russian).
equipment 25
III. Vacuum
Applications
30. Evaporation
and sputtering 30
24
1174. Reduced pressure system, protected against entry of air. A vacuum system is described, which is fitted with a safety valve with a predetermined shut-off device, which automatically closes whenever air enters the outer end of the container. The outer container is made of a series of 4-6 separate cylindrical vessels, interconnected by means of conical constrictions which reduce the flow of gases so that a robust safety valve with a shut-off time of several 100 set, is adequate to avoid leakage of air into the system. R Jean, (CSF-Compagnie Generale Sam File), German Patent (Cl. B OIj), 3 Feb 1966; French Patent
appl3
May
1962, 24
1175. Valves.
(USSR)
1965, 860, (in Russian). 30 1178. The deposition of silicon upon sapphire substrates.
A technique was developed for depositing silicon on single-crystal sapphire substrates composition of SiH,/Hz mixtures. Electron Laue reflection examinations of these films patterns. P H Robinson and C W Mueller, Trans Me/ail
single crystal films of via the pyrolytic dediffraction and X-ray revealed single crystal Sot oj’ AIME,
30
from PriborJJ i Tekh Eksper,
2 Feb 1966, German Appl23
408
236 (3),
Observations of calibrated epitaxial nickel films on (111) copper. (Netherlands) Nickel was evaporated in high vacuum from a calibrated source, one monolayer at a time, on a clean (111) copper single crystal substrate. Excellent order in arrangement of condensed nickel atoms with the same orientation as the substrate, but with the lattice spacing of Ni, was observed when the substrate was maintained at about 200°C during evaporation. Each successive monolayer grew epitaxially with respect to these layers immediately below it, always with the lattice spacing of nickel. C A Haque and H E Farnsworth, SItrfbce Science, 4 (2), 1966, 195-200. 30 1180. Carbide coatings on carbon resistors to prevent vaporization. (USA) Carbon resistors of any shape are heated to 2000-2300’ by electric resistance or induction in a vacuum of about 10m5mm while exposed to vapour arising from a melt of a metal forming a very refractory carbide. H R Smith, Jr, (Temesral Metallurgical Corp), US Patent 3,230,110, (Cl I I7-228),
1965).
(USA)
1966,268-274.
A glandless vacuum gate valve with a conditional flow-passage diameter of 300 mm is described. Its kinematic circuit and a diagram of its operation are given. A I Pipko et al, Instrum and Exper Tech, Dee 1965, 713, (Trurrsluted 3, May/June
: 20
Development tendencies of high-vacuum engineering. Part I. See abstract number 115 1. 30 : 20 Development tendencies of high-vacuum engineering. Part II. See abstract number 1152. 30 1177. Oriented growth of oxide lilms on beryllium. (USSR) The beryllium specimens were prepared by vacuum-melting and by hot-pressing. The dependence of oxide film growth on temperature is discussed. L D Kolomiets and V K Khorenko, Fiz Metal i Mefalloved, 20 (6),
1179.
(Great Brifain)
The valve allows periodic samples to be taken from a number of chambers through each of which gas is flowing. Two small-bore rubber tubes lead to the atmosphere and gas analyzer, respectively. J B Watkins and B C Peacock, Lab Practice, 14 (II), 1965, 1295.
1,210,004, 3 pages.
: 17
Cryogenic instrumentation. II. Sensing flow and composition. See abstract number 1138.
24 1173. An electrically-operated two-way gas valve.
(USSR)
18 Jan 1966, Appl22
Jan 1962: 4 pages. 30
1181. Vapour deposition of semiconductor materials. (Greaf Brifain) Anon, Siemens and Halske AG, Brirish Patent 1,019,080, (Cl C 23c), Aug 1962; 7pages