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Features of pulsed electron contact with sodium chloride layer. (USSR)
Classified abstracts 2380-2390 and oil decomposition products are dcsorbed. ionized and accelerated IO the cathode. S P Bugaev et al, IX l/U% Rz, No 2, 1975. 35-37 (i/l R~~ssiorr).
The results of the examination of an ultrahigh-frequency method for the measurement of longitudinal velocity distribution of electrons in plasma are presented. The experiments have been performed in a plasma-beam discharge at residual gas pressures of 10-I IO IO-* torr.
of modern times, characterized by the world energy crisis, and has led to widespread use of the most sophisticated vacuum systems for solid state fabrication and for obtaining high vacuum in the auxiliary devices of atomic reactors. This brings about the necessity to introduce the fundamentals of vacuum technology into the higher technical (engineers, junior engineers, technicians, etc.) who will later be employed to improve devices trsing high vacuum. Our aim is to present a concise and universal system, characterized by the simplicity of its use and its comparatively low price, despite the great number of its components. (Israel).
D V Gorozhanin
M Shteiner
I2
2380. Development of a high-frequency method of velocity distribution function of the electrons.
et al, Z/r T&/I
Fiz, 45 (I),
2381. Formation of an electron beam high-voltage diode with plasma emitter.
for the measurement (USSR)
1975, 41-48
with
large
cross
(irr Russia/~).
section
in a
(USSR) To obtain an electron beam with a large cross section, a plasma source with cold cathodes was used. Al A electron beam with pulse duration of 100 ~LSCC,cross section of 35 .’ 35 cm2 and electron energy of 250 keV has been extracted from the contracted discharge in the magnetic field. G S Kazmin
Irs
l.Jtiiiz.
et al, rra,r.s
of 3r~l Ukraitr
Vol I, Kharkov
1974. 146-148
C’onJ on Elec/rorr (bt Rwsiarr).
Optics
and
2382. Investigation of the factors determining the ion focusation gas-discharge electron sources with hollow-anodes. (USSR)
in
The factors which determine the ion focusation in gas-discharge sources of electrons based on gas-discharge sources of electrons based on high-voltage discharge with cold cathode and hollow anode are investigated. The diameter of the erosion zone of the cathode due to bombardment of the cathode by ions and fast neutral particles is used as a parameter characterising the ion focusation. The cxperiments show that the diameter of the erosion zone projected on the plane perpendicular to the source axis does not depend on the cathode shape, it decreases with the increase in voltage of the discharge in the range of IO to 30 kV and increases with the current growth from 5 to 100 mA and it does not depend on pressure in the range of 8 ,.: low3 to I.2 x IO-’ torr. The obtained results are explained by the assumption that the ion focusation depends on elongation of the cathode potential fall region which determines the configuration of the electric field. Yu E Krevndel
Ifs
Uti/iz,w
et al. Trafo
oT3rd
Vol I, Kharkov
Ukrain
C’onfo~r
i974, 258-262 (ifi
Elecfrott Russian).
Oorics 1
mrd
12 2383. Features
of pulsed
electron
contact
with
sodium
chloride
layer.
(USSR)
The kinetics of formation of negative space charge in a sodium chloride layer with a thickness of 5 pm sealed vacuum tightly to the vacuum chamber are investigated at pulsed electron beam contact at presence of an electric field in the layer. It is found that the space charge generated in the surface layer plays the role of an electrode. The current through the layer at high fields in excess of IO5 V/cm is due to liberation of electrons from the space charge by thermionic emission. S G Ekhanin, Rad Elekrrotr, 20 (4), 1975, 792-795 (itI Russian). I2 2384.
Universal
ion source.
(USSR)
An ion source is described which is based on a discharge with hot cathode and oscillating electrons in magnetic field. The plasma concentration in the source is enhanced with the aid of magnetic trapping of electrons in the cathode region and electron-optical contraction of plasma. The discharge is excited in metal vapours in the regime of selfsputtering at a pressure of lo-’ torr in the regioo of output aperture. D Kh Abdrashitova and M B Cuseva, 7’rarrsacf of3rd Ukruitte Repub/ Conf at1 Electron Oprics and 11s Appl, Vol I, Kharkov 1974, 164-166 (in
II.
Russion).
Vacuum
20. PUMPING
apparatus
and
auxiliaries
SYSTEMS 20
2385. Educational systems for training in vacuum technology. (GB) The last decades have witnessed great developments in the electronic and nuclear industries. This development has resulted from problems
et al,
Vnctcurrl,
26, (4/5),
1976.
193-195.
20 2386. An apparatus for quenching foils in ultrahigh vacuum. (GB) An ultrahigh vacuum apparatus designed for contamination-free quenching of foils is described. Using this system, a high density of dislocation loops and stacking fault tctrahedra has been produced in seven FCC metals including nickel, a metal in which widespread defect structures have not been reported previously. The quench rates attained were measured by two comparable methods and were found to depend principally on the thermal conductivity of the specimen material. The maximum rates range from 4OOO”Cs-’ for Cu to 120°C s-l for stainless steel. (USA) K H Westmacott and R L Peck, J P/rys E: Sci hrswwn, 9(7) 1976, 521-523. 22. GAUGES
AND MEASUREMENT
2387. An atmospheric
OF LOW PRESSURES 22
pressure
ionization
(API)
source
for a magnetic
sector mass spectrometer. (GB) An Atmospheric Pressure Ionization (API) source has been built for a magnetic sector mass spectrometer. The ionization reactions. initiated by electrons from a Nickel-63 source are carried out in a flowing gas stream at atmospheric pressure. The reaction chamber is separated from the mass analyzer high vacuum region by a 50 pm aperture. The API mass spectrometer is being differentially pumped in order to maintain a pressure of IO-’ torr in the analyzer region. This is being achieved by a 6 in. high speed pumping system connected to the ion source housing. The API source is electrically isolated from ground and connected to the accelerating high voltage of the mass spectrometer. (Israel) J Yinon
and H G Boettger,
Vucrrutn,
26 (4/5)
1976,
159-161.
22 2388. Air pollution monitoring by negative-ion mass spectrometry. (GB) In this research the use of negative-ion mass spectrometry for the monitoring of oxygen-containing gases has been demonstrated. Electron impact by low-energy electrons of oxygen-containing gases will result in dissociative electron capture forming O-. By introducing into a negative-ion mass spectrometer a mixture of SOZ, NO, NO1, CO, COZ and O,, focussing O- (m/e = 16) onto the collector, and varying the electron energy, a spectrum of peaks is obtained, which are characteristic of the oxygen-containing molecules in the mixture. The results of this research will be the basis of the design of a small negative-ion mass spectrometer system for the monitoring of oxygencontaining gases in air. (Israel) Y Gleitman
et al, Vaarrm~,
26, (4/5),
1976,
163-166.
22 2389. Extension
of rate of rise method
for calibrating
vacuum
gauges.
(GB)
The known rate of rise technique applicable to the molecular flow regime only has been extended to include other flow regimes too. Theory has been confirmed experimentally for various gauges. Previous knowledge of constriction conductance used in the calibration procedure of a gauge is unnecessary in the extended method. Further information like the pressure that exists in a moIecular beam on leaving its guiding tubing, is attainable. It is also shown that recalibration of commercial gauges can be easily carried out so that expensive reference standards can be saved. (Israel) H 2 Sar-El and E Pellach, Vucuum, 26 (4/5), 1976,137-141. 22 2390. The calibration processes. (GB)
of vacuum
measuring
instruments
for industrial
This paper describes the construction and operation of a gauge calibration system in accordance with the recommendations laid down in the draft British Standards Institution document number 41
The results of the examination of an ultrahigh-frequency method for the measurement of longitudinal velocity distribution of electrons in plasma are presented. The experiments have been performed in a plasma-beam discharge at residual gas pressures of 10-I IO IO-* torr.
of modern times, characterized by the world energy crisis, and has led to widespread use of the most sophisticated vacuum systems for solid state fabrication and for obtaining high vacuum in the auxiliary devices of atomic reactors. This brings about the necessity to introduce the fundamentals of vacuum technology into the higher technical (engineers, junior engineers, technicians, etc.) who will later be employed to improve devices trsing high vacuum. Our aim is to present a concise and universal system, characterized by the simplicity of its use and its comparatively low price, despite the great number of its components. (Israel).
D V Gorozhanin
M Shteiner
I2
2380. Development of a high-frequency method of velocity distribution function of the electrons.
et al, Z/r T&/I
Fiz, 45 (I),
2381. Formation of an electron beam high-voltage diode with plasma emitter.
for the measurement (USSR)
1975, 41-48
with
large
cross
(irr Russia/~).
section
in a
(USSR) To obtain an electron beam with a large cross section, a plasma source with cold cathodes was used. Al A electron beam with pulse duration of 100 ~LSCC,cross section of 35 .’ 35 cm2 and electron energy of 250 keV has been extracted from the contracted discharge in the magnetic field. G S Kazmin
Irs
l.Jtiiiz.
et al, rra,r.s
of 3r~l Ukraitr
Vol I, Kharkov
1974. 146-148
C’onJ on Elec/rorr (bt Rwsiarr).
Optics
and
2382. Investigation of the factors determining the ion focusation gas-discharge electron sources with hollow-anodes. (USSR)
in
The factors which determine the ion focusation in gas-discharge sources of electrons based on gas-discharge sources of electrons based on high-voltage discharge with cold cathode and hollow anode are investigated. The diameter of the erosion zone of the cathode due to bombardment of the cathode by ions and fast neutral particles is used as a parameter characterising the ion focusation. The cxperiments show that the diameter of the erosion zone projected on the plane perpendicular to the source axis does not depend on the cathode shape, it decreases with the increase in voltage of the discharge in the range of IO to 30 kV and increases with the current growth from 5 to 100 mA and it does not depend on pressure in the range of 8 ,.: low3 to I.2 x IO-’ torr. The obtained results are explained by the assumption that the ion focusation depends on elongation of the cathode potential fall region which determines the configuration of the electric field. Yu E Krevndel
Ifs
Uti/iz,w
et al. Trafo
oT3rd
Vol I, Kharkov
Ukrain
C’onfo~r
i974, 258-262 (ifi
Elecfrott Russian).
Oorics 1
mrd
12 2383. Features
of pulsed
electron
contact
with
sodium
chloride
layer.
(USSR)
The kinetics of formation of negative space charge in a sodium chloride layer with a thickness of 5 pm sealed vacuum tightly to the vacuum chamber are investigated at pulsed electron beam contact at presence of an electric field in the layer. It is found that the space charge generated in the surface layer plays the role of an electrode. The current through the layer at high fields in excess of IO5 V/cm is due to liberation of electrons from the space charge by thermionic emission. S G Ekhanin, Rad Elekrrotr, 20 (4), 1975, 792-795 (itI Russian). I2 2384.
Universal
ion source.
(USSR)
An ion source is described which is based on a discharge with hot cathode and oscillating electrons in magnetic field. The plasma concentration in the source is enhanced with the aid of magnetic trapping of electrons in the cathode region and electron-optical contraction of plasma. The discharge is excited in metal vapours in the regime of selfsputtering at a pressure of lo-’ torr in the regioo of output aperture. D Kh Abdrashitova and M B Cuseva, 7’rarrsacf of3rd Ukruitte Repub/ Conf at1 Electron Oprics and 11s Appl, Vol I, Kharkov 1974, 164-166 (in
II.
Russion).
Vacuum
20. PUMPING
apparatus
and
auxiliaries
SYSTEMS 20
2385. Educational systems for training in vacuum technology. (GB) The last decades have witnessed great developments in the electronic and nuclear industries. This development has resulted from problems
et al,
Vnctcurrl,
26, (4/5),
1976.
193-195.
20 2386. An apparatus for quenching foils in ultrahigh vacuum. (GB) An ultrahigh vacuum apparatus designed for contamination-free quenching of foils is described. Using this system, a high density of dislocation loops and stacking fault tctrahedra has been produced in seven FCC metals including nickel, a metal in which widespread defect structures have not been reported previously. The quench rates attained were measured by two comparable methods and were found to depend principally on the thermal conductivity of the specimen material. The maximum rates range from 4OOO”Cs-’ for Cu to 120°C s-l for stainless steel. (USA) K H Westmacott and R L Peck, J P/rys E: Sci hrswwn, 9(7) 1976, 521-523. 22. GAUGES
AND MEASUREMENT
2387. An atmospheric
OF LOW PRESSURES 22
pressure
ionization
(API)
source
for a magnetic
sector mass spectrometer. (GB) An Atmospheric Pressure Ionization (API) source has been built for a magnetic sector mass spectrometer. The ionization reactions. initiated by electrons from a Nickel-63 source are carried out in a flowing gas stream at atmospheric pressure. The reaction chamber is separated from the mass analyzer high vacuum region by a 50 pm aperture. The API mass spectrometer is being differentially pumped in order to maintain a pressure of IO-’ torr in the analyzer region. This is being achieved by a 6 in. high speed pumping system connected to the ion source housing. The API source is electrically isolated from ground and connected to the accelerating high voltage of the mass spectrometer. (Israel) J Yinon
and H G Boettger,
Vucrrutn,
26 (4/5)
1976,
159-161.
22 2388. Air pollution monitoring by negative-ion mass spectrometry. (GB) In this research the use of negative-ion mass spectrometry for the monitoring of oxygen-containing gases has been demonstrated. Electron impact by low-energy electrons of oxygen-containing gases will result in dissociative electron capture forming O-. By introducing into a negative-ion mass spectrometer a mixture of SOZ, NO, NO1, CO, COZ and O,, focussing O- (m/e = 16) onto the collector, and varying the electron energy, a spectrum of peaks is obtained, which are characteristic of the oxygen-containing molecules in the mixture. The results of this research will be the basis of the design of a small negative-ion mass spectrometer system for the monitoring of oxygencontaining gases in air. (Israel) Y Gleitman
et al, Vaarrm~,
26, (4/5),
1976,
163-166.
22 2389. Extension
of rate of rise method
for calibrating
vacuum
gauges.
(GB)
The known rate of rise technique applicable to the molecular flow regime only has been extended to include other flow regimes too. Theory has been confirmed experimentally for various gauges. Previous knowledge of constriction conductance used in the calibration procedure of a gauge is unnecessary in the extended method. Further information like the pressure that exists in a moIecular beam on leaving its guiding tubing, is attainable. It is also shown that recalibration of commercial gauges can be easily carried out so that expensive reference standards can be saved. (Israel) H 2 Sar-El and E Pellach, Vucuum, 26 (4/5), 1976,137-141. 22 2390. The calibration processes. (GB)
of vacuum
measuring
instruments
for industrial
This paper describes the construction and operation of a gauge calibration system in accordance with the recommendations laid down in the draft British Standards Institution document number 41