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Difmanometer—a gas flow meter with automatic correction
Classified abstracts 36 47 18 36. Dissociation of molecular ions formed by charge exchange in an in-line tandem mass spectrometer. (USA) Dissociations o f the molecular ions of several alkenes, alcohols, a n d ketones, f o r m e d in charge-exchange collisions were studied using an in-line t a n d e m mass spectrometer. Collision c h a m b e r pressures were in the range 10 -'~ to 5 ~ 10 :~ torr. T h e effects of both incident ion translational energy a n d collision c h a m b e r t e m p e r a t u r e on the observed dissociations were examined. F o r m o s t o f the molectdes studied, the extent of f r a g m e n t a t i o n of the molecular ion increases as the kinetic energy is increased, indicating that energy is being converted f r o m the translational m o d e s into target excitation. T h e m a g n i t u d e o f this energy conversion appears to be small. Higher collision c h a m b e r t e m p e r a t u r e s led to m o r e extensive fragmentation. C h a r g e exchange spectra obtained in the present study are c o m p a r e d with b r e a k d o w n g r a p h s previously determined with similar experim e n t s in perpendicular type t a n d e m m a s s spectrometers. C Lifshitz and T O Tiernan, J Chem P/O's, 57 (41, 15th Aug 1972, 1515-1534.
T h e m e t h o d of plasma diagnostics by scattering of laser radiation on electrons was applied to the m e a s u r e m e n t of the electron temperature a n d concentration in T u m a n - 2 , an axially symmetrical toroidal magnetic trap with longitudinal current. T h e m e a s u r e m e n t s were performed at a discharge current in p l a s m a of 4.5 and 9 kA, pressure of hydrogen in the c h a m b e r of 9 10 -r' and 6 10 ~ torr, and quasi-stationary longitudinal magnetic field of 3.2 and 4 kOe. V K Gusev el al, Zh Tekh Fiz, 42 (2), Feb 1972, 340-343 (in Russian). 19. R A D I A T I O N 19 42. Effect of a proton beam on the generation of CO2 gas laser. (USSR) A b e a m of protons with energy of several M e V was passed t h r o u g h the laser m e d i u m in the pressure range of 1 to 10 tort. T h e effect on the generation of power of a CO.z laser is investigated. Experimental results are discussed. S A Golubev et al, Zh EAsper Teor Fiz, 62 (21, Feb 1972, 458~-65
(in Russian).
18 37. Ionization of argon by electron impact. (USA) G r e a t care was taken to fulfill the requirements of accurate ionization efficiency curves. More details on the a p p a r a t u s will be published in the future. T h e ionization efficiency curves for A r ~- and Ar '-'+ were m e a s u r e d for electron energies from threshold to 300 eV. Structure in the A r + curve was confirmed and a r g u m e n t s a n d evidence are put forward to s u p p o r t the view that this structure is due to production of the ion via various channels (in particular the auto-ionization channels) rather t h a n to " c o m p e t i t i o n " between the Ar + and Ar a+ channels as has been suggested recently. A Crowe et al, J Chem Phys, 57 (4), 15th Aug 1972, 1620-1625.
19 43. Power laser arrangement and investigation of the efficiency of high-temperature plasma heating. (USSR) A n experimental, high-power n e o d y m i u m glass laser a r r a n g e m e n t with radiation energy up to 1300 J is described. F o r m a t i o n of a shock wave in air at 15 torr as a result of expansion of a target in the gas is studied by m e a n s of ultra-high-speed p h o t o g r a p h y . N G Basov et al, Zh Eksper Teor Fi:, 62 (I), Jan 1972, 203-212 tin
18:30 38. Properties of film emitters with two-dimensional transformations in the film. System I r ( l l l ) - C . ( U S S R ) Properties of film emitters with two-dimensional t r a n s f o r m a t i o n in the adlayer are studied. T h e b o n d energy between a d a t o m s a n d the critical t e m p e r a t u r e o f phase t r a n s f o r m a t i o n are calculated for the system I r ( l l I)-C, experimentally investigated by the m e t h o d s o f thermionic emission and surface ionization. A qualitative m e t h o d o f description of the thermionic emission of the film emitters is developed. N D Potekhina and A Ya Tontegode, Zh Tekh Fiz, 42 (1), Jan 1972, 162-170 (in Russian).
20 44. Efficiency of sorhing structures in vacuum systems with quasi-point gas sources. (USSR) An analytical m e t h o d of calculating of probability of capture of molecule injected by quasi-point axially symmetrical gas source is presented for stationary molecular regime in systems at t h e r m o d y n a m i c equilibrium, with sorbing walls. T h e m e t h o d leads to integration o f equations of diffusion scattering for particles incident on the sorbing structure having a sticking coefficient different from unity, taking account of different variants of trajectories and geometrical characteristics o f the system gas s o u r c e - s o r b i n g structure. Graphical dependences of the probability of capture for a uniform gas source and for source with cosine distribution at different sticking coefficients on the characteristic d i m e n s i o n s of sorbing structures, are given. T h e developed m e t h o d permits selection of geometry of the p u m p i n g system with sorbing walls, in systems with quasi-point gas sources. N A lvandikova and G L Saksaganskiy, Zh Tekh I-7:, 42 (2), Feb 1972. 436~!-41 (in Russian).
18 : 31 39. On the mechanism of current oscillations in Knudsen caesium diode. (USSR) T h e processes occurring in the K n u d s e n p l a s m a of a caesium diode are investigated. F o r m a t i o n of a virtual c a t h o d e near emitter is experimentally d e m o n s t r a t e d . T h e m e c h a n i s m o f current oscillations is discussed. T h e dependence o f the period o f current oscillations on the argon partial pressure in the caesium v a p o u r mixture is measured. I G Gverdtsiteli et al, Zh Tekh Fig, 42 (1), Jan 1972, 103 110 (in
Russian). 18 : 31 40. Influence of non-metallic inclusions and films in micro-regions of a cathode on vacuum breakdown. (USSR) Influence of non-metallic inclusions a n d thin c a r b o n a n d oxide films in micro-regions of the surface o f an iron c a t h o d e on the b r e a k d o w n of small inter-electrode gaps of 0.05 m m is investigated at residual gas pressure of a b o u t 10 -~ torr. Inclusions of crystalline quartz, quartz glass, c o r u n d u m , iron oxide and iron sulphide are examined. T h e construction of the experimental device is described. D i s c h a r g e was excited between a spherical m o l y b d e n u m anode, 1 rnm in diameter and a c a t h o d e 7 m m in diameter. T h e experimental device was evacuated by a mercury diffusion p u m p . It is f o u n d that the traces of discharge action at v a c u u m b r e a k d o w n are concentrated on n o n metallic inclusions. T h e non-metallic inclusions do not m a r k e d l y influence the electric strength o f vacuuna gap. T h i n c a r b o n films on iron surface lower the electric strength by m o r e t h a n three times. V V Kraft and V M Stuehenkov, Zh Tekh Fiz, 42 (1), Jan 1972, 88-93
(in Russian). 18:32 41. Measurement of electron temperature and concentration by scattering of laser radiation in plasma in the equipment Tuman-2. ( U S S R ) 34
Russian).
II.
V a c u u m a p p a r a t u s and auxiliaries
20. P U M P I N G S Y S T E M S
22. G A U G E S 22 45. Difmanometer--a gas flow meter with automatic correction. ( U S S R) A d i f m a n o m e t e r a flow meter with accuracy of 4 per cent is described which automatically indicates deviations of pressure and tcrnperature of gas or vapour from determined values. T h e m e a s u r i n g a p p a r a t u s consists o f a bellows assembly (converter of pressure difference), m a n o m e t r i c converter o f pressure, t h e r m o m e t r i c converter of temperature, integrator a n d recording mecbanism. V I Chegodaev, Izmerit Tekh, No 1, 1972, 49 (in Russian1. 46. Ion source for mass-spectrometric analysis of active gases. (USSR) C o n s t r u c t i o n of an ion source for mass-spectrometric analysis of active gases is described. G a s is admitted to the ionization c h a m b e r only t h r o u g h glass tubes. I I Skorokhodov et al, Zavods'k Lab, 38 (1), 1972, 119 (in Russian). 22 47. The problem of temperature in the metrology of vacuum. (Czechoslovak ia) T h e complexity of telnperature problems in the calibration of low pressures is discussed. T h e question is divided into three parts: the significance of the a m b i e n t temperature for n o n - t h e r m a l mechanical v a c u u m gauges, the significance of temperature for low pressure
T h e m e t h o d of plasma diagnostics by scattering of laser radiation on electrons was applied to the m e a s u r e m e n t of the electron temperature a n d concentration in T u m a n - 2 , an axially symmetrical toroidal magnetic trap with longitudinal current. T h e m e a s u r e m e n t s were performed at a discharge current in p l a s m a of 4.5 and 9 kA, pressure of hydrogen in the c h a m b e r of 9 10 -r' and 6 10 ~ torr, and quasi-stationary longitudinal magnetic field of 3.2 and 4 kOe. V K Gusev el al, Zh Tekh Fiz, 42 (2), Feb 1972, 340-343 (in Russian). 19. R A D I A T I O N 19 42. Effect of a proton beam on the generation of CO2 gas laser. (USSR) A b e a m of protons with energy of several M e V was passed t h r o u g h the laser m e d i u m in the pressure range of 1 to 10 tort. T h e effect on the generation of power of a CO.z laser is investigated. Experimental results are discussed. S A Golubev et al, Zh EAsper Teor Fiz, 62 (21, Feb 1972, 458~-65
(in Russian).
18 37. Ionization of argon by electron impact. (USA) G r e a t care was taken to fulfill the requirements of accurate ionization efficiency curves. More details on the a p p a r a t u s will be published in the future. T h e ionization efficiency curves for A r ~- and Ar '-'+ were m e a s u r e d for electron energies from threshold to 300 eV. Structure in the A r + curve was confirmed and a r g u m e n t s a n d evidence are put forward to s u p p o r t the view that this structure is due to production of the ion via various channels (in particular the auto-ionization channels) rather t h a n to " c o m p e t i t i o n " between the Ar + and Ar a+ channels as has been suggested recently. A Crowe et al, J Chem Phys, 57 (4), 15th Aug 1972, 1620-1625.
19 43. Power laser arrangement and investigation of the efficiency of high-temperature plasma heating. (USSR) A n experimental, high-power n e o d y m i u m glass laser a r r a n g e m e n t with radiation energy up to 1300 J is described. F o r m a t i o n of a shock wave in air at 15 torr as a result of expansion of a target in the gas is studied by m e a n s of ultra-high-speed p h o t o g r a p h y . N G Basov et al, Zh Eksper Teor Fi:, 62 (I), Jan 1972, 203-212 tin
18:30 38. Properties of film emitters with two-dimensional transformations in the film. System I r ( l l l ) - C . ( U S S R ) Properties of film emitters with two-dimensional t r a n s f o r m a t i o n in the adlayer are studied. T h e b o n d energy between a d a t o m s a n d the critical t e m p e r a t u r e o f phase t r a n s f o r m a t i o n are calculated for the system I r ( l l I)-C, experimentally investigated by the m e t h o d s o f thermionic emission and surface ionization. A qualitative m e t h o d o f description of the thermionic emission of the film emitters is developed. N D Potekhina and A Ya Tontegode, Zh Tekh Fiz, 42 (1), Jan 1972, 162-170 (in Russian).
20 44. Efficiency of sorhing structures in vacuum systems with quasi-point gas sources. (USSR) An analytical m e t h o d of calculating of probability of capture of molecule injected by quasi-point axially symmetrical gas source is presented for stationary molecular regime in systems at t h e r m o d y n a m i c equilibrium, with sorbing walls. T h e m e t h o d leads to integration o f equations of diffusion scattering for particles incident on the sorbing structure having a sticking coefficient different from unity, taking account of different variants of trajectories and geometrical characteristics o f the system gas s o u r c e - s o r b i n g structure. Graphical dependences of the probability of capture for a uniform gas source and for source with cosine distribution at different sticking coefficients on the characteristic d i m e n s i o n s of sorbing structures, are given. T h e developed m e t h o d permits selection of geometry of the p u m p i n g system with sorbing walls, in systems with quasi-point gas sources. N A lvandikova and G L Saksaganskiy, Zh Tekh I-7:, 42 (2), Feb 1972. 436~!-41 (in Russian).
18 : 31 39. On the mechanism of current oscillations in Knudsen caesium diode. (USSR) T h e processes occurring in the K n u d s e n p l a s m a of a caesium diode are investigated. F o r m a t i o n of a virtual c a t h o d e near emitter is experimentally d e m o n s t r a t e d . T h e m e c h a n i s m o f current oscillations is discussed. T h e dependence o f the period o f current oscillations on the argon partial pressure in the caesium v a p o u r mixture is measured. I G Gverdtsiteli et al, Zh Tekh Fig, 42 (1), Jan 1972, 103 110 (in
Russian). 18 : 31 40. Influence of non-metallic inclusions and films in micro-regions of a cathode on vacuum breakdown. (USSR) Influence of non-metallic inclusions a n d thin c a r b o n a n d oxide films in micro-regions of the surface o f an iron c a t h o d e on the b r e a k d o w n of small inter-electrode gaps of 0.05 m m is investigated at residual gas pressure of a b o u t 10 -~ torr. Inclusions of crystalline quartz, quartz glass, c o r u n d u m , iron oxide and iron sulphide are examined. T h e construction of the experimental device is described. D i s c h a r g e was excited between a spherical m o l y b d e n u m anode, 1 rnm in diameter and a c a t h o d e 7 m m in diameter. T h e experimental device was evacuated by a mercury diffusion p u m p . It is f o u n d that the traces of discharge action at v a c u u m b r e a k d o w n are concentrated on n o n metallic inclusions. T h e non-metallic inclusions do not m a r k e d l y influence the electric strength o f vacuuna gap. T h i n c a r b o n films on iron surface lower the electric strength by m o r e t h a n three times. V V Kraft and V M Stuehenkov, Zh Tekh Fiz, 42 (1), Jan 1972, 88-93
(in Russian). 18:32 41. Measurement of electron temperature and concentration by scattering of laser radiation in plasma in the equipment Tuman-2. ( U S S R ) 34
Russian).
II.
V a c u u m a p p a r a t u s and auxiliaries
20. P U M P I N G S Y S T E M S
22. G A U G E S 22 45. Difmanometer--a gas flow meter with automatic correction. ( U S S R) A d i f m a n o m e t e r a flow meter with accuracy of 4 per cent is described which automatically indicates deviations of pressure and tcrnperature of gas or vapour from determined values. T h e m e a s u r i n g a p p a r a t u s consists o f a bellows assembly (converter of pressure difference), m a n o m e t r i c converter o f pressure, t h e r m o m e t r i c converter of temperature, integrator a n d recording mecbanism. V I Chegodaev, Izmerit Tekh, No 1, 1972, 49 (in Russian1. 46. Ion source for mass-spectrometric analysis of active gases. (USSR) C o n s t r u c t i o n of an ion source for mass-spectrometric analysis of active gases is described. G a s is admitted to the ionization c h a m b e r only t h r o u g h glass tubes. I I Skorokhodov et al, Zavods'k Lab, 38 (1), 1972, 119 (in Russian). 22 47. The problem of temperature in the metrology of vacuum. (Czechoslovak ia) T h e complexity of telnperature problems in the calibration of low pressures is discussed. T h e question is divided into three parts: the significance of the a m b i e n t temperature for n o n - t h e r m a l mechanical v a c u u m gauges, the significance of temperature for low pressure