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Oxide cathode emission in a low pressure pulse discharge
Classified
abstracts
1940-1952
beam focusing and the velocity analyzer. Representative spectra, obtained with this source, for argon, nitrogen, neon, helium and hydrogen are given as well as results of studies on the variation in energy distribution as a function of discharge voltage, extraction voltage and nature of the ions. M Perdrix et al, Le Vide, 22 (130), Jlt&Aug
1967, 189-195 (in French).
influence of this effect on the frequency pulling of microwave tubes is mentioned. S A Kornilov, Radiotekh Elektron, 12 (8). Aug 1967, 1415-1423 (in Russian). 1947. Oxide
cathode
emission
in a low
pressure
18 discharge.
pulse
18 (USSR) A new ion source is proposed based on the following principle: electrons emitted by a cathode are accelerated by an electrode but pass through an orifice in the electrode to the electron collector with voltage lower than the accelerating voltage. Typical values are 1,000 V for the accelerating electrode and from 200 to 800 V for the electron collector. By electron impact on gas molecules, ions are produced and the ions are self-focused to the electron beam axis. Through an orifice in the electron collectors, ions are fed to the ion collector at suitable voltage, eg- 1000 V. In this way, ion beams are produced without external electrical and magnetic focusing fields, and with an ionization efficiency of the order of 10 4 to 10 3. The basic advantage of the new design is the possibility of producing polarized ions at pressures of 10m7to lo-~” torr. N S Zinchenko and G N Zinchenko, Zh Tekh Fiz, 37 (7), July 1967,
(USSR) Ni of the highest purity was coated by BaCO, : SrCO, films of equimolar composition and the system was used in diodes filled with H, at a pressure of 0.5 torr. It was found that in the one-shot regime, during pulses of duration longer than 10 psec. the cathode current decreases but in the free-running regime after 8 working hours at 900°C or after 1 working hour at 950°C the cathode current is constant during pulses of the duration up to 1.2 msec and, for very long pulses, increases due to overheating of the cathode. For cathodes working with current densities of the order of IO A/cm” and with long current pulses the transition from saturated current regime to spacecharge limited current regime was observed during each pulse. Zerofield currents of 4 to 7 A/cm2 at 800‘ C, 9 to 12 A/cm* at 85O’C and of 16 to 20 A/cm2 at 900°C were measured for these diodes and these values do not depend on the pulse duration. L N Vagin, Radiotekh Elektron. 12 (8), Aug 1967, 1440-1447 (in
125881268
Russian).
1940. High vacuum ion source without focusing fields.
(in Russian).
1941. Nonequilibrium
ionization
in a low
voltage
arc
18 discharge.
(USSR) In the first part of the work, equations are derived describing nonequilibrium ionization in a caesium, low voltage, arc discharge caused by electron distribution relaxations due to Coulomb interaction between emitted and plasma electrons. In the second part, the speed of ionization at any point of the interelectrode space and the total number of ions originating per set are computed. These problems are connected with investigations of thermionic emission energy converters. I P Stakhanov, Zh Tekh Fir, 37 (7), July 1967, 1277-l 297 (in Russian). 18 1942. Effects of the space charge in high-frequency
discharge in gases.
(USSR) Breakdown voltages were measured for air and argon in the frequency range of 100 to 1600 MHz and in the pressure range of 10m3to 100 torr in a coaxial waveguide and between two planes. In the case of the coaxial gap the strong influence of the space charge on the breakdown voltages was observed at decimetric waves. In homogeneous HF fields a similar effect was found but at lower frequencies. G A Anashkin, Zh Tekh Fiz, 37 (8), Aug 1967, 1481-1487 (in Russian). 1943. Potential and density distribution of charged (USSR) discharge plasma with oscillating electrons.
particles
18 in a
A theoretical model of a Penning discharge is given and the distribution of potential and of electron and ion densities are calculated. L V Brzhechko and 0 S Pavlichenko, Zh Tekh Fiz, 37 (8), Aug 1967, 1508-I 513 (in Russian). 1944. Calculation of the gain of the simplest longitudinal ionization. (USSR)
open ion source
18 with
The efficiency of an ion source with longitudinal impact ionization is calculated and the optimal working regimes are discussed. G I Slobodenyuk, Zh Tekh Fiz, 37 (8), Aug 1967, 1540-1542 (in Russian). 18 1945. Experimental investigation of short-range forces and threshold ionization in atomic collisions. (USSR) For the cases of He-He, N,-N,, Kr-Kr, Ne-Ne and Ar-Ar inter-
actions it is shown that investigations high-speed beams are effective. V B Leonas and A V Sermyagin, 1549 (in Russian).
of small angle scattering using
Zh Tekh Fiz, 37 (8), Aug 1967,154718
emission electron conductance
of grid gaps.
electron
emission
of
some
high-resistance
18 films.
As a new material for secondary electron multiplier dynodes, SnO, prepared by different methods (by pyrolysis, drop method, oxidation of metal films evaporated in vacua, reduction in H, atmosphere) was investigated. By enriching the film with metal, the films become more stable, especially during current overload but their resistance is lower and the secondary electron emission coefficient falls from 3 to 3.5 to 2.5 to 3. Bv addition of 10 to 20 ner cent of In into enriched SnO,, films with good properties and secondary electron emission coefficients of about 3 to 3.2, were obtained. A M Tyutikov and M N Toiseva, 1448-1453 (in Russian). 1949. Electron
emission
Radiotekh
of Pt-Ba,
Elektron,
Pd-Ba,
Rh-Ba
12 (8), Aug 1967,
and Au-Ba
18 alloys.
(USSR) Work functions were measured for alloys of 2 per cent of Ba with several metals. At IlOO’K the work function of Au-Ba alloy is 2.2 eV and at 1300’K that of Pt-Ba is 2.2 eV, Pd-Ba, 2.5 eV, and Rh-Ba, 2.2 eV. The temperature dependence of the work function did not exceed 5 x IO-” eV/grad for any alloy. B Ch Dyubua et al, Radiotekh (in Russian).
Elektron,
12 (8), Aug 1967, 1523-1524
18 1950. Electron emission from polymers subjected to mechanical vibrations. (USSR) A ball mill filled with polymer was subjected to mechanical vibrations
and electron emission of the order of lo3 to 10” electrons/set, caused by the mechanical destruction, was observed for polyethylene, polystyrene, polymethyl methacrylate and for polyvinyl alcohol. After interrupting the vibrations the exoemission from the polymers was observed. The mechanism of this emission is briefly discussed. A M Polyakov, Dokl Akad Nauk SSSR, 175 (l), 1st July 1967, 72-75 (in Russian). 1951. Investigation
of the exoelectron
emission
in sliding
18 :53 friction.
(USSR) From exoelectron emission characteristics, the mechanism of growth and depletion of oxide layers on metals may be investigated, as is shown for the case of sliding friction on steel, iron and aluminium. V D Evdokimov, Dokl Akad Nauk SSSR, 565 (in Russian).
175 (3). 21st July 1967, 563-
: 31
(USSR) Equations are derived and, from experiments with reflex klystrons having tungsten and copper grids, the results are confirmed for the electron conductance of grid gaps caused by secondary emission. The reactive component of the conductance is negative and usually is higher than the primary electron conductance component. The 1946. Secondary
1948. Secondary (USSR)
1952. On a phenomenon
due to high-frequency
gaseous
18 discharge.
(USSR) Breakdown voltages have been measured for argon at 5 x 10m2to 100 torr in the frequency range of 100 to 1600 MHz and the effect of the space charge causing deviations from diffusion theory is discussed. G A Anashkin, Zzv VI/Z Fiz, 10 (7), 1967, 13 l-l 34 (in Russian). 671
abstracts
1940-1952
beam focusing and the velocity analyzer. Representative spectra, obtained with this source, for argon, nitrogen, neon, helium and hydrogen are given as well as results of studies on the variation in energy distribution as a function of discharge voltage, extraction voltage and nature of the ions. M Perdrix et al, Le Vide, 22 (130), Jlt&Aug
1967, 189-195 (in French).
influence of this effect on the frequency pulling of microwave tubes is mentioned. S A Kornilov, Radiotekh Elektron, 12 (8). Aug 1967, 1415-1423 (in Russian). 1947. Oxide
cathode
emission
in a low
pressure
18 discharge.
pulse
18 (USSR) A new ion source is proposed based on the following principle: electrons emitted by a cathode are accelerated by an electrode but pass through an orifice in the electrode to the electron collector with voltage lower than the accelerating voltage. Typical values are 1,000 V for the accelerating electrode and from 200 to 800 V for the electron collector. By electron impact on gas molecules, ions are produced and the ions are self-focused to the electron beam axis. Through an orifice in the electron collectors, ions are fed to the ion collector at suitable voltage, eg- 1000 V. In this way, ion beams are produced without external electrical and magnetic focusing fields, and with an ionization efficiency of the order of 10 4 to 10 3. The basic advantage of the new design is the possibility of producing polarized ions at pressures of 10m7to lo-~” torr. N S Zinchenko and G N Zinchenko, Zh Tekh Fiz, 37 (7), July 1967,
(USSR) Ni of the highest purity was coated by BaCO, : SrCO, films of equimolar composition and the system was used in diodes filled with H, at a pressure of 0.5 torr. It was found that in the one-shot regime, during pulses of duration longer than 10 psec. the cathode current decreases but in the free-running regime after 8 working hours at 900°C or after 1 working hour at 950°C the cathode current is constant during pulses of the duration up to 1.2 msec and, for very long pulses, increases due to overheating of the cathode. For cathodes working with current densities of the order of IO A/cm” and with long current pulses the transition from saturated current regime to spacecharge limited current regime was observed during each pulse. Zerofield currents of 4 to 7 A/cm2 at 800‘ C, 9 to 12 A/cm* at 85O’C and of 16 to 20 A/cm2 at 900°C were measured for these diodes and these values do not depend on the pulse duration. L N Vagin, Radiotekh Elektron. 12 (8), Aug 1967, 1440-1447 (in
125881268
Russian).
1940. High vacuum ion source without focusing fields.
(in Russian).
1941. Nonequilibrium
ionization
in a low
voltage
arc
18 discharge.
(USSR) In the first part of the work, equations are derived describing nonequilibrium ionization in a caesium, low voltage, arc discharge caused by electron distribution relaxations due to Coulomb interaction between emitted and plasma electrons. In the second part, the speed of ionization at any point of the interelectrode space and the total number of ions originating per set are computed. These problems are connected with investigations of thermionic emission energy converters. I P Stakhanov, Zh Tekh Fir, 37 (7), July 1967, 1277-l 297 (in Russian). 18 1942. Effects of the space charge in high-frequency
discharge in gases.
(USSR) Breakdown voltages were measured for air and argon in the frequency range of 100 to 1600 MHz and in the pressure range of 10m3to 100 torr in a coaxial waveguide and between two planes. In the case of the coaxial gap the strong influence of the space charge on the breakdown voltages was observed at decimetric waves. In homogeneous HF fields a similar effect was found but at lower frequencies. G A Anashkin, Zh Tekh Fiz, 37 (8), Aug 1967, 1481-1487 (in Russian). 1943. Potential and density distribution of charged (USSR) discharge plasma with oscillating electrons.
particles
18 in a
A theoretical model of a Penning discharge is given and the distribution of potential and of electron and ion densities are calculated. L V Brzhechko and 0 S Pavlichenko, Zh Tekh Fiz, 37 (8), Aug 1967, 1508-I 513 (in Russian). 1944. Calculation of the gain of the simplest longitudinal ionization. (USSR)
open ion source
18 with
The efficiency of an ion source with longitudinal impact ionization is calculated and the optimal working regimes are discussed. G I Slobodenyuk, Zh Tekh Fiz, 37 (8), Aug 1967, 1540-1542 (in Russian). 18 1945. Experimental investigation of short-range forces and threshold ionization in atomic collisions. (USSR) For the cases of He-He, N,-N,, Kr-Kr, Ne-Ne and Ar-Ar inter-
actions it is shown that investigations high-speed beams are effective. V B Leonas and A V Sermyagin, 1549 (in Russian).
of small angle scattering using
Zh Tekh Fiz, 37 (8), Aug 1967,154718
emission electron conductance
of grid gaps.
electron
emission
of
some
high-resistance
18 films.
As a new material for secondary electron multiplier dynodes, SnO, prepared by different methods (by pyrolysis, drop method, oxidation of metal films evaporated in vacua, reduction in H, atmosphere) was investigated. By enriching the film with metal, the films become more stable, especially during current overload but their resistance is lower and the secondary electron emission coefficient falls from 3 to 3.5 to 2.5 to 3. Bv addition of 10 to 20 ner cent of In into enriched SnO,, films with good properties and secondary electron emission coefficients of about 3 to 3.2, were obtained. A M Tyutikov and M N Toiseva, 1448-1453 (in Russian). 1949. Electron
emission
Radiotekh
of Pt-Ba,
Elektron,
Pd-Ba,
Rh-Ba
12 (8), Aug 1967,
and Au-Ba
18 alloys.
(USSR) Work functions were measured for alloys of 2 per cent of Ba with several metals. At IlOO’K the work function of Au-Ba alloy is 2.2 eV and at 1300’K that of Pt-Ba is 2.2 eV, Pd-Ba, 2.5 eV, and Rh-Ba, 2.2 eV. The temperature dependence of the work function did not exceed 5 x IO-” eV/grad for any alloy. B Ch Dyubua et al, Radiotekh (in Russian).
Elektron,
12 (8), Aug 1967, 1523-1524
18 1950. Electron emission from polymers subjected to mechanical vibrations. (USSR) A ball mill filled with polymer was subjected to mechanical vibrations
and electron emission of the order of lo3 to 10” electrons/set, caused by the mechanical destruction, was observed for polyethylene, polystyrene, polymethyl methacrylate and for polyvinyl alcohol. After interrupting the vibrations the exoemission from the polymers was observed. The mechanism of this emission is briefly discussed. A M Polyakov, Dokl Akad Nauk SSSR, 175 (l), 1st July 1967, 72-75 (in Russian). 1951. Investigation
of the exoelectron
emission
in sliding
18 :53 friction.
(USSR) From exoelectron emission characteristics, the mechanism of growth and depletion of oxide layers on metals may be investigated, as is shown for the case of sliding friction on steel, iron and aluminium. V D Evdokimov, Dokl Akad Nauk SSSR, 565 (in Russian).
175 (3). 21st July 1967, 563-
: 31
(USSR) Equations are derived and, from experiments with reflex klystrons having tungsten and copper grids, the results are confirmed for the electron conductance of grid gaps caused by secondary emission. The reactive component of the conductance is negative and usually is higher than the primary electron conductance component. The 1946. Secondary
1948. Secondary (USSR)
1952. On a phenomenon
due to high-frequency
gaseous
18 discharge.
(USSR) Breakdown voltages have been measured for argon at 5 x 10m2to 100 torr in the frequency range of 100 to 1600 MHz and the effect of the space charge causing deviations from diffusion theory is discussed. G A Anashkin, Zzv VI/Z Fiz, 10 (7), 1967, 13 l-l 34 (in Russian). 671