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142. Vacuum as an electrical insulator
Classified Abstracts
140-145
Classified General 10.
Vacuum
Abstracts
Science
Vacuum Science and Technology
tions and for small gaps. However, down mechanism is still uncertain.
10 : 37 : 53
Production of Low Pressures
13 143. Furnace mounting and control system for Ainsworth vacuum automatic recording balance. U.S.A. A commercially available vacuum automatic recording balance has been equipped with programme control and furnaces so that it may be used for thermogravimetric studies. The complete system has been tested at pressures less than 0.1 mmHg. Comparatively light-weight furnaces are used. For convenience of operation, radiation shields take the place of the major part (Authors) of the insulation.
11 :23 :43 :47:25 140. Evaporation plant for operation in the pressure range 1Om6to 10-a torr. Great Britain. A new elastomer, Viton ‘A’, having a low degassing rate and permeability, makes it possible to obtain a much lower ultimate pressure in routine evaporation plant by using the substance for “ 0 ” rings and gaskets. By circulating liquid nitrogen through a Meissner type trap in the vacuum vessel, the ultimate vacuum can be further improved since the refrigerated trap acts as a fast pump for vapours desorbed in the vessel. Two types of plant with which it is possible to operate in D. A. P. the pressure range lo+ to 1O-8 torr are described. S.
K. Bateman and T. Putner,
P. D. Garn, et al., Rev. Sci. Instrum., 33 (3), March 1962,293-297. 13 : 36 : 25 : 20 Full scale apparatus to probe freeze-drying. See Abstr. No. 221.
Vacnique, 2 (6), April 1962,2-6.
Vapour pumping with rotary vacuum pumps.
11:21:57 See Abstr. No. 176.
Equipment requirements in impregnating systems. 218.
11 : 21 : 18
14.
Modern valve pumping. See Abstr. No. 173.
12.
12 : 20 141. Pressure measurement in non-baked ultra-high vacuum systems. U.S.A. The use of high-speed cryogenic pumping systems has resulted in the obtaining of pressures in the ultra-high vacuum region without the use of a bakeout. Under these conditions two new pressure-measurement problems are introduced due to directional pressure effects and outgassing of the gauge tabulation. These effects can cause reading errors in excess of one A solution is presented decade. This paper discusses theseeffects. which eliminates both types of errors and hence allows for improved pressure measurement in nonbaked ultra-high vacuum systems. (Author) D. J. Santeler, Rev. Sci. Znstrum., 33 (3), March 1962, 283-287.
13.
13 : 35 See Abstr. No.
Kinetic Theory of Gases
14 : 40 144. Studies on vacuum condensation point (V.C.P.) in subliiatography (1). Japan. V.C.P. in sublimatography was studied to establish the sublimatographic separation of mixed systems. When sublimed vapour condensed and crystallized on the wall of a glass tube with temperature gradient, a certain critical point of condensation had The ratio y=Ph/PC, where Ph was the pressure of been obtained. vapour phase and PC the saturated vapour pressure at the critical point temperature, had a significance and showed a characteristic value for each substance. The mean values of y for mercuric chloride, mercuric bromide, mercuric iodide, stannic iodide, arsenic trioxide and phosphorus pentoxide were 1.50, 1.40, 1.72, (In Japanese). 1.42, 1.79 and 1.99 respectively. (Author)
Measurement of Low Pressures
Operation of a Bayard-Alpert ionization gauge. 183.
for larger gaps the break(Authors)
L. Cranberg and R. Hawley, Res. Appl. Zndustr., 15 (8), Aug. 1962, 347-352.
Ultrafine metal powder. See Abstr. No. 224.
11.
and Engineering
K. Yoshimura,
Japan Analyst, 11(4), April 1962, 397-400.
14 : 40 145. Studies on vacuum condensation point (V.C.P.) in sublimatogr=phy (2). Japan. In order to examine the effect of vapour flow on the V.C.P. in sublimatography, fundamental experiments were carried out on two methods (effusion method and direct method). The relation between the vapour flow F(mol/sec) in the glass tube with temperature gradient and the V.C.P. was studied and an empirical formula (yP$ = k . F was obtained, where y was Ph/Ps with Ph = pressure of vapour phase and Ps = saturated vapour pressure at the temperature of V.C.P., and F was a value concerned with the heating temperature of the substance t,,. From these relations it is evident that V.C.P. depends upon th, and under a fixed condition, the position where the substance condenses in the tube with temperature gradient is determined by th.
12 : 22 : 18 See Abstr. No.
Vacuum Applications
13 : 18 142. Vacuum as an electrical Insulator. U.S.A. and Great Britain. High vacuum as an electrical insulator is finding increasing application mainly in particle accelerators and space travel. Many investigations have been undertaken attempting to determine the mechanism of breakdown and it appears to be understood for several special electrode configura63
140-145
Classified General 10.
Vacuum
Abstracts
Science
Vacuum Science and Technology
tions and for small gaps. However, down mechanism is still uncertain.
10 : 37 : 53
Production of Low Pressures
13 143. Furnace mounting and control system for Ainsworth vacuum automatic recording balance. U.S.A. A commercially available vacuum automatic recording balance has been equipped with programme control and furnaces so that it may be used for thermogravimetric studies. The complete system has been tested at pressures less than 0.1 mmHg. Comparatively light-weight furnaces are used. For convenience of operation, radiation shields take the place of the major part (Authors) of the insulation.
11 :23 :43 :47:25 140. Evaporation plant for operation in the pressure range 1Om6to 10-a torr. Great Britain. A new elastomer, Viton ‘A’, having a low degassing rate and permeability, makes it possible to obtain a much lower ultimate pressure in routine evaporation plant by using the substance for “ 0 ” rings and gaskets. By circulating liquid nitrogen through a Meissner type trap in the vacuum vessel, the ultimate vacuum can be further improved since the refrigerated trap acts as a fast pump for vapours desorbed in the vessel. Two types of plant with which it is possible to operate in D. A. P. the pressure range lo+ to 1O-8 torr are described. S.
K. Bateman and T. Putner,
P. D. Garn, et al., Rev. Sci. Instrum., 33 (3), March 1962,293-297. 13 : 36 : 25 : 20 Full scale apparatus to probe freeze-drying. See Abstr. No. 221.
Vacnique, 2 (6), April 1962,2-6.
Vapour pumping with rotary vacuum pumps.
11:21:57 See Abstr. No. 176.
Equipment requirements in impregnating systems. 218.
11 : 21 : 18
14.
Modern valve pumping. See Abstr. No. 173.
12.
12 : 20 141. Pressure measurement in non-baked ultra-high vacuum systems. U.S.A. The use of high-speed cryogenic pumping systems has resulted in the obtaining of pressures in the ultra-high vacuum region without the use of a bakeout. Under these conditions two new pressure-measurement problems are introduced due to directional pressure effects and outgassing of the gauge tabulation. These effects can cause reading errors in excess of one A solution is presented decade. This paper discusses theseeffects. which eliminates both types of errors and hence allows for improved pressure measurement in nonbaked ultra-high vacuum systems. (Author) D. J. Santeler, Rev. Sci. Znstrum., 33 (3), March 1962, 283-287.
13.
13 : 35 See Abstr. No.
Kinetic Theory of Gases
14 : 40 144. Studies on vacuum condensation point (V.C.P.) in subliiatography (1). Japan. V.C.P. in sublimatography was studied to establish the sublimatographic separation of mixed systems. When sublimed vapour condensed and crystallized on the wall of a glass tube with temperature gradient, a certain critical point of condensation had The ratio y=Ph/PC, where Ph was the pressure of been obtained. vapour phase and PC the saturated vapour pressure at the critical point temperature, had a significance and showed a characteristic value for each substance. The mean values of y for mercuric chloride, mercuric bromide, mercuric iodide, stannic iodide, arsenic trioxide and phosphorus pentoxide were 1.50, 1.40, 1.72, (In Japanese). 1.42, 1.79 and 1.99 respectively. (Author)
Measurement of Low Pressures
Operation of a Bayard-Alpert ionization gauge. 183.
for larger gaps the break(Authors)
L. Cranberg and R. Hawley, Res. Appl. Zndustr., 15 (8), Aug. 1962, 347-352.
Ultrafine metal powder. See Abstr. No. 224.
11.
and Engineering
K. Yoshimura,
Japan Analyst, 11(4), April 1962, 397-400.
14 : 40 145. Studies on vacuum condensation point (V.C.P.) in sublimatogr=phy (2). Japan. In order to examine the effect of vapour flow on the V.C.P. in sublimatography, fundamental experiments were carried out on two methods (effusion method and direct method). The relation between the vapour flow F(mol/sec) in the glass tube with temperature gradient and the V.C.P. was studied and an empirical formula (yP$ = k . F was obtained, where y was Ph/Ps with Ph = pressure of vapour phase and Ps = saturated vapour pressure at the temperature of V.C.P., and F was a value concerned with the heating temperature of the substance t,,. From these relations it is evident that V.C.P. depends upon th, and under a fixed condition, the position where the substance condenses in the tube with temperature gradient is determined by th.
12 : 22 : 18 See Abstr. No.
Vacuum Applications
13 : 18 142. Vacuum as an electrical Insulator. U.S.A. and Great Britain. High vacuum as an electrical insulator is finding increasing application mainly in particle accelerators and space travel. Many investigations have been undertaken attempting to determine the mechanism of breakdown and it appears to be understood for several special electrode configura63