摘要:

A rf interrogated sonar location system for freely floating buoys is described. The location of an array of up to three buoys may be determined on an almost continuous basis within a radius of 500 m from a shipboard monitoring station. Location accuracy of typically ±0.5 m at 200‐m range, low cost, and ease of operation are the major features of the system.

ISSN:0034-6748    

DOI:10.1063/1.1137425

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A Commodore PET computer with analog‐to‐digital and digital‐to‐analog converters may be used as a programmable gated integrator with gate lengths ≥1 ms. Multiple gates and delays of programmed length may be obtained with suitable machine language code accessed frombasic.

ISSN:0034-6748    

DOI:10.1063/1.1137426

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Heating and biasing of a thin film during deposition is frequently desirable to improve the structural quality of the film and to remove entrapped gases and loosely bound species on the surface. A large‐diameter electrode assembly which allows both operations to occur simultaneously with a resulting variation in film thickness across a 2.54‐cm wafer of ≤0.1 &mgr;m is described.

ISSN:0034-6748    

DOI:10.1063/1.1137427

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Quasistatic measurements of thed31piezoelectric strain coefficient are presented for PZT‐5H material. Bulk data analysis techniques have been applied to assess the voltage‐dependent contribution to the induced strain.

ISSN:0034-6748    

DOI:10.1063/1.1137428

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A mechanism is described for adjustment under ultrahigh vacuum of the optical alignment of gratings in a vertically dispersing grazing incidence monochromator. The mechanism is based on two pairs of broad leaf springs and it allows rotation of the grating, of up to one degree, around two mutually perpendicular axes with respect to the photon energy scan axis. Measurements for a grazing incidence monochromator show that to achieve optimum resolution the adjustment of the grating should be better than 0.1°.

ISSN:0034-6748    

DOI:10.1063/1.1137429

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A new dc transient method is described for fast measurements of dielectric permittivity in the &mgr;Hz frequency region. A square‐wave voltage pulse is applied to the dielectric instead of the usual step voltage pulse. The whole transient current is measured two times faster than in the conventional method using the step voltage.

ISSN:0034-6748    

DOI:10.1063/1.1137430

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We introduce the use of a pulse transformer as an improvement in the drive circuit of the ‘‘hairpin looppop’’sign for a pulsed molecular‐beam source. The virtue of this device is that it can produce the high currents necessary to drive the hairpin at low voltage. In addition, it minimizes theI2Rpower loss of former designs while allowing for proper impedance matching of the leads to the power supply, thus lowering the voltage requirements necessary to drive the circuit.

ISSN:0034-6748    

DOI:10.1063/1.1137431

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Methods are described for insulating and thermostating a glass syringe that can be manipulated by hand to transfer liquids over a temperature range from −100 to +80 °C. This syringe has been used to transfer liquid sulfur dioxide solutions at low temperatures and molten salts above room temperature.

ISSN:0034-6748    

DOI:10.1063/1.1137432

出版商:AIP    

年代:1983

数据来源: AIP