Classified abstracts lQO!3-1922 quick checks on the readings of the upper and lower levels of the manometer fluid as the pressure is slowly changing. M M Kreitman and D Cooper, J Vat Sci Tech&, 3, 1966, 221. 22 1905. Mass spectrometertype MI-1308. (USSR) An advertisement of the spectrometer for the mass range 2-450 with argon sensitivity 4.1O-4 per cent. Further information can be obtained from: Special X-ray Apparatus Design Centre, 78 Mafookhtinskiy Pr, Leningrad K-l 12, USSR. (USSR) Anon, Pribory i Tekh Eksper, 11 (3), May-June 1966, 237 (in Russian). 22 1906. New hoMlament ionization gauge - - with low residual current.
(USA) The design and performance of a new type hot-filament ionization gauge is described. The ions are extracted from the ionization region. focused through an aperture in a shield electrode and then coll&e~ on a short, fine wire. The sensitivity factor of this gauge is about 13 torr-’ for nitrogen. The ratio of the soft X-ray flux reading the collector of the new gauge to that of a Bayard-Alpert gauge is calculated, and the X-ray limit of the new gauge estimated to be 3 x lo-l8 torr. P A Redhead, J Vat Sci Technol, 3 (4). 1966, 173-180. 22 1907. Voltage dependence of Bayard-Alpert gauge chara&ristics.
25 1915. Fasteners for cryogenic applications. (USA) Bolts of three alloys-A286. Unitemn 212. and inconel718-exhibit mechanical properties at cjogenic &mFer&ure (-423°F) which are up to 35 per cent better than those at room temperature. E F Gowen, Jr and J Glackin, Metal Progress, 90 (I), Jury 1966, 4648. 25 1916. Techniquea for using lkpdd helium in very low temperature apparatus. (USA) A discussion of what is known experimentally about the thermal contact problem at very low temperatures is given. Liquid ‘He is a particularly promising contact agent. Methods of using liquid bHe, thermometry using cerium magnesium nitrate, and solutions to the filling and isolation problem using an open capillary are discussed. 0 E Vil&es and J C WheutIey, Rev Sci Instrum, 37, July 1966, 819-831. 25 1917. A cryogenic device. (Great Britain) A striated, discontinuous, thin metallic film can be vacuum deposited onto a substrate by positioning the depositing material in a preferred direction and at a high angle of incidence to the substrate surface. T D Clark (Mu/lard Ltd), British Patent 1,023,519 (CI HOIf), 23 March 1966, Appl25 Ott 1963,6 pages.
(Japan)
The dependence of the pumping speed and sensitivity of a BayardAlpert gauge on the electrode potentials were measured for He, Ar, and Kr at pressures of about lo-’ torr. K Ishikawa, Japan J Appl Phys, 4,1966, 461. 22 1908. A technique for micromanometry. (USA) A description is given of a rugged instrument capable of resolving pressure differences of about 10 microtorr in the flow of gaseous media and adaptable to remote operation. H J Carper and R A Burton, Amer Inst Aeron Astronaut, 4,1966,549. 23. Plumbing
23 1909. Sealing connections for high vacuum using gold-wire. (France) The parameters that influence the choice of connectors are mentioned. The use of a gold-wire gave very good results. After the necessary stock is bought, the gold wire can be recovered, the only additional cost is the cost of spinning the gold-wire. The deformation load being relatively small, the method is made reproducible and positive. R Souchet, L.e Vide, 123,1966,235 (in French). 23 1910. The corrosion resistance of joints made by diffusion welding in a vacuum. (USSR) S E Ushakova, Life Metalloved i Obrabotka Metal, Davleniem, 1965, 62-66 (in Russian). 24. Valves 1911. Gas sampling valve for closed system sampling. K Abel, Anal Chem, 38, May 1966.806-807. 25. Baffles, traps and refrigeration
24 (USA)
equipment
25 1912. New type of traps using liquid air. (France) Description and diagrams of new design of traps are given in this note. F Devaux, Le Vide, 123,1966,247 (in French). 25 1913. Fast actkm bgf8es. (France) J Camon et al, Le Vi&, 123,1966,249 (in French). 25 1914. Simple cooling system with drculating helhun gas. (Netherlands) Describes a system in which cold helium gas is forced through a heat exchanger on thermal contact with a sample that is to be cooled to approximately 15°K or higher. L Pfeiffer and P W Kearon Jr, 40,1966,357.
26. Automatic
protective
and control equipment
26 1918. Methods and tools for determining mechanical properties of metallic materials at cryogenic temperatures. (Italy) The methods and tools for determining impact strength. tensile strength, fatigue limit, hardness, torsion, &ee$ and she& for metals at cryogenic temperatures are reviewed. C Caneva, Calore, 36,1966, 562-577 (in Italian). 26 1919. Maximum pressure protection device. (USSR) Authors describe in detail the design of the protection device which consists of a thermocouple gauge with solid state and magnetic amplifiers. (USSR) V G Anikm and I A Okorokov, Zzmerit Tekh, (5), May 1966,83-85 (in Russian).
27. Leak detectors
and leak detection
27 1920. Leak detector for furnace-cooling systems. (Germany) The detection of small leaks in encased fluid-circulating - systems, like _ those used in high-temperature carbide furnaces, is made possible by monitoring: the atmosphere of make-up fluid i.7 the surge tank connected to the system. F Ritter et al, German Patent 1,2X3,449 (Cl, C21c) 31 March 1966, Appll4 Sept 1956,2 pages. 27 1921. Some inherent peculiarities in the detection of leaks in complex units. (France) Knowledge of helium transitory systems is very useful to establish a leak detection project for an important and complex unit. The authors refer to the neglect of theoretical studies of this problem and propose to show how the employment of an electrical analogy permits simplification of the problem. C Guilbard and A Guihery, Le Vide, 123, 1966, 212-220 (in French). 27 1922. The sensitivity and calibratkm of a mass ‘spectrometerleak detector. (China) The most important characteristic of a mass spectrometer leak detector is its sensitivity. Various definitions of the sensitivity and its calibration methods are reviewed. By the use of a Pt wire glass type standard leak and a simple filling system, it is convenient t&calibrate the sensitivitv within the range of leak rate from 10-O to 1O-18l-tot-r/ set strictly aºg to defi&ion, and to study the relations between the output indication of the instrument and leak rate and between sensitivity and working conditions. L-C Ch’a and T-C Hsueb, Ch’ing Hua Ta Hsueh Hsueh Pao, 12,1965, 7-22 (in Chinese).