摘要:

This paper supplies information on hydrostatic pressure techniques up to 20 000 kg/cm2under two headings. Under general pressure techniques, low temperature seals, experience with small diameter tubing, a pressure measuring bridge, and various tubing seals are described. Under optical techniques, optical windows of sapphire, germanium, and silicon, suitable pressure fluids, and a mechanism for moving samples inside a pressure vessel for use to 10 000 kg/cm2are discussed.

ISSN:0034-6748    

DOI:10.1063/1.1716294

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The problem of estimating particle momenta under the simultaneous presence of magnetic deflection and Coulomb scattering is considered. This problem is of practical interest when nuclear emulsion plates are exposed under fields of multihundred kilogauss currently available from pulsed magnets. The estimation of momentum is separated into two parts, each utilizing the magnetic and the Coulomb effect, respectively. In this way one can fully utilize the numerous estimation techniques already developed and available in the literature for each of these two estimates. This separation, however, is carried out in such a way that the magnetic and the Coulomb estimate are statistically independent, and hence can be readily combined for an improved accuracy.

ISSN:0034-6748    

DOI:10.1063/1.1716295

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

A spin echo method adapted to the measurement of long nuclear relaxation times (T2) in liquids is described. The pulse sequence is identical to the one proposed by Carr and Purcell, but the rf of the successive pulses is coherent, and a phase shift of 90° is introduced in the first pulse. Very longT2values can be measured without appreciable effect of diffusion.

ISSN:0034-6748    

DOI:10.1063/1.1716296

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

According to Faraday's law of induction an electric field will be induced in a medium moving relative to a magnetic field. This induced electric field is proportional to the intensity of the magnetic field and to the relative velocity of the moving medium. When applied to media of arbitrary electrical conductivity and dielectric constant, it is seen that any potential difference that arises in connection with the induced electric field is attenuated by the shunting effect of the permittivity of free space. For most media this shunting effect is negligible; for media of extremely low conductivity, however, the effect is appreciable. Finally the effect of the electrical properties of the containing pipe is investigated.

ISSN:0034-6748    

DOI:10.1063/1.1716297

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

A microscope, with coordinate motions of 21×15 cm which may be used in the analysis of large nuclear plates is described with particular attention given to constructional details. The design includes a magnetic clutch for fixing plate position, a rotating super‐stage and dial indicators to observe both horizontal and vertical movement. A stage noiseD¯noise≦0.029 &mgr; for cell lengths up to 1 mm was obtained.

ISSN:0034-6748    

DOI:10.1063/1.1716298

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Various ways of pulsing photomultipliers are investigated. Some drawbacks inherent to the conventional methods are pointed out; a new pulsing method is suggested and experimentally studied, which avoids these inconveniences.

ISSN:0034-6748    

DOI:10.1063/1.1716299

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

Some considerations on ``energy aberrations'' in electron spectrometers containing accelerating (decelerating) components are discussed with regard to their role in the measurement of the energies of electrons. Based on these considerations, design criteria are obtained for an electrostatic decelerating component for a given electron absorption spectrometer. The design criteria are derived by treating the problem of a charged particle in an electrostatic field by means of the Hamiltonian method in classical mechanics, and are found to be related to the curvature of the electrostatic field.

ISSN:0034-6748    

DOI:10.1063/1.1716300

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The theory of the constant‐current hot‐wire circuit for measurement of very high gas temperatures is developed and it is shown that such a system may be used above the melting point of the wire itself.

ISSN:0034-6748    

DOI:10.1063/1.1716301

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The response of a commercially available liquid scintillator to D(d,n)He3neutrons and to &ggr; radiation from several standard sources has been measured. It is found that the pulse height response to &ggr;‐ray energy is linear in the energy range 0.5 to 2.6 Mev, and that the fast neutron detection efficiency of a disk scintillator 5 cm thick is about 30% in the neutron energy range 2 to 3.5 Mev, and varies with neutron energyEas&xgr;(E)=0.146+0.45/E+0.82,whereEis measured in Mev.

ISSN:0034-6748    

DOI:10.1063/1.1716302

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The maintenance of isobaric conditions at pressures of the order of 10 000 lb/in.2is sometimes a difficult operation in transport studies. A manostat has been devised which will maintain isobaric conditions with a precision of about 1 part in 100 000 at pressures from 500 to 10 000 lb/in.2. The equipment functions satisfactorily as a pressure transducer for control purposes.

ISSN:0034-6748    

DOI:10.1063/1.1716303

出版商:AIP    

年代:1958

数据来源: AIP