摘要:

A constant‐tension coil whose structural pathway resembles an archer’s bow is described. This shape permits the construction of demountable high‐field toroidal magnets with joints at the inner major radius where they are most useful. The support arrangement redistributes the coil tension to maintain the joints under compression and ensure reliable performance.

ISSN:0034-6748    

DOI:10.1063/1.1136646

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We have invented a device for quickly emptying a dewar of liquid nitrogen without having to invert the dewar. The liquid is forced out by compressed nitrogen gas, using a type of pump which does not require the dewar to be sealed.

ISSN:0034-6748    

DOI:10.1063/1.1136647

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The construction of a variable power electrodeless microwave discharge and cavity using a microwave oven magnetron and power supply is demonstrated. The apparatus is convenient to use, durable, and inexpensive.

ISSN:0034-6748    

DOI:10.1063/1.1136648

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A procedure for interfacing a 32 K PET Computer with digital‐to‐analog and analog‐to‐digital converters is documented.

ISSN:0034-6748    

DOI:10.1063/1.1136649

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The electrical resistance measurement of metallic conducting materials can be doneinsituin a diamond‐window, high‐pressure cell with a four‐lead arrangement designed to avoid contact and lead‐wire resistances. Variants of the general method include designs for long (several cm) and short (less than 1 mm) length of samples material, and for the use of solid and fluid pressure‐transmitting media.

ISSN:0034-6748    

DOI:10.1063/1.1136650

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A technique is described to estimate the contact resistance of an ohmic contact, under dynamic conditions, applied to a high resistivity photoconductor. It has been used to estimate the contact resistance of an ohmic contact (Au–Ge) applied to a semiinsulating Cr‐doped GaAs (p≊108W cm).

ISSN:0034-6748    

DOI:10.1063/1.1136651

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A simple method of compensating an inductive strip shunt is to use another shunt in series with it, with equal inductance but lesser resistance. When the voltages induced in these shunts are subtracted in a compensating circuit, the compensated shunt acts like a pure resistance. A compensated shunt of thin tantalum foil, having an effective resistance of 200 mW, was made.

ISSN:0034-6748    

DOI:10.1063/1.1136652

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Light that is reflected from the input and output faces of an optical waveguide may be used to form an image of the input face and the focused input beam.

ISSN:0034-6748    

DOI:10.1063/1.1136653

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A novel double‐window system for shock tubes useful with vacuum UV atomic resonance absorption spectrometry is described. This system allows the shock tube to be baked to 400 °C under high vacuum.

ISSN:0034-6748    

DOI:10.1063/1.1136623

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A mechanically‐improved spark gap, in an open groove along a glass or quartz rod, is described in this paper. The output is about 0.5 cps with a flash duration of less than a microsecond. The effective source size is limited by a 1.6‐mm diam. hole in an aperture plate. Ease of assembly and replacement of faulty components is the important improvement over earlier spark gaps. Mach apparently was the first to study bullets and shock waves in air with illumination from an open spark gap. A bibliography of the history of spark discharges can be found in books by Edgerton and Frungel.

ISSN:0034-6748    

DOI:10.1063/1.1136624

出版商:AIP    

年代:1981

数据来源: AIP