摘要:

The monopole spectrometer uses an rf electric field between a two‐electrode configuration for analyzing ions of differente/m. One electrode has a right‐angle cross section, the other has a circular cross section whose center is located on the bisector of the right angle. The properties of the spectrometer are derived from an approximate equation for the ion motion. An instrument is described which achieves a sensitivity of 0.3 mA/mm Hg atm/&Dgr;m=190 with good peak shape, using an analyzing field of 27‐cm length.

ISSN:0034-6748    

DOI:10.1063/1.1718110

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

The apparatus contains a reference surface (gold) and provision for evaporating the experimental surface onto a rotating metal plate. Circuits used to measure the surface potential difference between the two metal surfaces are described. The apparatus has a rapid and continuous response to changes in the surface potential difference (SPD) between an experimental and a reference surface. As a result, the resolution of the initial variation of the SPD on sorption of oxygen on evaporated iron has been materially increased. The apparatus can be modified to allow SPD measurement on single crystals or catalyst surfaces.

ISSN:0034-6748    

DOI:10.1063/1.1718124

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A sample holder is described which has been used for the investigation of dielectric properties of ferroelectric materials from room temperature to over 700°C at frequencies up to 100 kc. It has also been used to observe hysteresis (D‐E) loops of ferroelectrics in ceramic and single crystal form.

ISSN:0034-6748    

DOI:10.1063/1.1718133

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A simple method for preparing evaporated thin films of silicon from an etched silicon filament is described. The method of mounting and processing the filament ensures low gas evolution during evaporation and makes possible the deposition of silicon films in a vacuum of ∼5×10−10Torr.

ISSN:0034-6748    

DOI:10.1063/1.1718107

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

Flux measurements of low‐energy, neutral and charged particles provide direct knowledge of plasma composition and energy distribution. We describe a particle analyzer for the energy range between a few electron volts and several thousand electron volts, which is sensitive to single ions and has an inherent time resolution of less than 50 m&mgr;sec. Experimental results are given for both energy and mass analysis of positive ions ejected by a pulsed‐arc plasma gun. Significant variations in composition and energy distributions are observed with variations in gun voltage. Preliminary results are presented on the detection of low‐energy neutral particles.

ISSN:0034-6748    

DOI:10.1063/1.1718108

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

An apparatus designed to measure the refractive indices of the inert gases over the temperature range 77 to 273°K and at pressures up to 100 atm is described. Techniques are given for calibration of the optical cell and the production of a suitable solid specimen. The accuracy of the method is discussed and it is shown how polarizability and compressibility may be deduced from the refractive index data.

ISSN:0034-6748    

DOI:10.1063/1.1718109

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A device for making NMR measurements in a double‐coil nuclear induction system under axial stress on single crystals in excess of 10 000 psi or hydrostatic pressure on powders, single crystals, or other materials up to 10 000 psi has been constructed of Fiberglas. This device is simple in design and operation and is relatively inexpensive. Results of measurements on I127in NaI powder, which exhibit the expected decrease in intensity with pressure, are given.

ISSN:0034-6748    

DOI:10.1063/1.1718111

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

A crystal sphere orienter for nonopaque crystals has been designed. It is used in conjunction with a petrographic microscope to orient crystal spheres optically.

ISSN:0034-6748    

DOI:10.1063/1.1718112

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

This paper describes the development of a new electromechanical method of measuring the densities of flowing cryogenic fluids. The instrument uses a movable section of flow passage, vibrated transversely at a constant amplitude and frequency, as the sensing element. A dynamometer, inserted between the flow passage and driver, continuously measures the acceleration reaction (product of mass and acceleration) of the fluid in the passage. A measure of this reaction is also a measure of the fluid density in the passage. Performance results indicate that the densitometer should be well suited for service in liquid oxygen and nitrogen single‐ and two‐phase flow systems, and with only minor changes for use with liquid hydrogen.

ISSN:0034-6748    

DOI:10.1063/1.1718113

出版商:AIP    

年代:1963

数据来源: AIP

摘要:

Well‐defined beams of thermal and long‐wavelength neutrons are often difficult to obtain because of reflection from collimator surfaces. Reflection is minimized if the product of the number of scatter centers per cm3and their net coherent scattering amplitude is as small a negative number as possible. This amplitude balancing can be achieved to almost any degree by the proper selection of organic compounds. When used as surface coatings, these compounds possess distinct advantages over other materials. Tetradecanoic acid (C14H28O2) has shown extremely low reflectivity and excellent properties as a surface coating.

ISSN:0034-6748    

DOI:10.1063/1.1718114

出版商:AIP    

年代:1963

数据来源: AIP