摘要:

A simple plasma source using microwave breakdown near cyclotron resonance in a low pressure gas has been developed. It consists of a tapered glass tube inserted through a waveguide that is terminated by a tunable short. By suitable choice of the degree of taper, the problem of strong temperature inhomogeneities (and sometimes hollow plasmas) frequently encountered with ECR plasma production can be overcome. Using relatively low microwave power levels, <3 W, the following ranges of electron temperatures and densities have been produced: 2 <Te<8.5 eV and 3 × 109<Ne<4 × 1010cm−3(the density is power limited).

ISSN:0034-6748    

DOI:10.1063/1.1684301

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

A pulsed Faraday effect rotator was built and used as an optical isolator for light at 1.06 &mgr;. The pulse mode simplified the problem of creating the high magnetic field strengths necessary to allow the use of a relatively short, low absorbance rotator material. A forward‐to‐backward transmission ratio of 36 dB was obtained using a 0.32 cm diam laser beam.

ISSN:0034-6748    

DOI:10.1063/1.1684302

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

Commercial available argon lasers are narrow bored, which can support only a limited number of modes. In order to suit the scan laser operation, a wide bore multimode laser is designed. This communication discusses the design procedure, technique, and apparatus setup for a helical inductively pumped wide bore argon laser. The experimental result and further improvement are also discussed.

ISSN:0034-6748    

DOI:10.1063/1.1684303

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

An automatic shutter intended for recording holograms with laser light is described. The shutter allows holographic recording material to be exposed until a preset exposure value is reached; it then automatically cuts off the laser beam. The automatic control on the exposure time is provided by a photoconductor cell placed near the recording material. Properly used, this shutter can eliminate the need to measure the light level illuminating the material. It also permits the laser power to vary over at least two orders of magnitude during the exposure without affecting the high diffraction efficiency of the recorded hologram.

ISSN:0034-6748    

DOI:10.1063/1.1684304

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

Strain is measured by recording the motion of fringes produced by laser light incident on adjacent pyramidal indentations in a specimen surface. The gauge length of this noncontacting technique is of the order of 0.1 mm. The theory of the fringe formation and the relation of fringe motion to strain are given along with an experimental evaluation of the validity of the technique. Biaxial strains can be measured both for known and unknown principal strain directions.

ISSN:0034-6748    

DOI:10.1063/1.1684305

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

The design of a simple mechanical magnetic circulating pump is given. The pump has been used in this laboratory for a wide range of applications. A pump of this design may be immersed in a bath within the temperature range of −200 to over +400°C and will operate at pressures up to 3500 kg/cm2, dependent upon the material of construction. A most significant design feature of the pump is the achievement of both chemical and mechanical cleanliness. No lubrication is required. The pump is self‐flushing with no trapping or pocketing of the circulated fluid possible. The pump is durable and reliable for long periods of operation. The drive for the pump is mounted external to the constant temperature bath, which prevents thermal transfer from the drive to the bath or the pump. The design incorporates a permanent magnet.

ISSN:0034-6748    

DOI:10.1063/1.1684306

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

The paper describes the construction and operation of a simple continuous dilution refrigerator which provides modest refrigeration to temperatures below 0.05 K. Both construction technique and cost are similar to what would be required to build a3He evaporative refrigerator.

ISSN:0034-6748    

DOI:10.1063/1.1684307

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

A simple compact recorder suitable as an alternative to the oscilloscope‐camera combination is described. The risetime of the recorder is 2 nsec and it has a dynamic range of 30 dB. The information is read out either electronically or by observing a magnetic domain wall which represents the recorded signal.

ISSN:0034-6748    

DOI:10.1063/1.1684308

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

A device is described that permits the remote attachment of standard weights, for calibration purposes, on the beam of an electronic microbalance that is enclosed in a vacuum chamber. The weights can be manipulated in a reproducible and imperturbable manner. The device consists of a self‐heating bimetallic element that controls the displacement of a suspension arm on which standard weights are suspended. The displacement of the arm is controlled electrically and can be operated in a vacuum tight chamber over a range of pressure.

ISSN:0034-6748    

DOI:10.1063/1.1684309

出版商:AIP    

年代:1970

数据来源: AIP

摘要:

Described here is a modification of the Varian HA‐100 spectrometer which permits convenient observation of13C NMR spectra at 25.1 MHz, with field/frequency stabilization based upon a19F lock at 94.1 MHz. All radio frequencies are derived from a synthesizer. The resulting stability permits efficient storing of repetitive experiments.

ISSN:0034-6748    

DOI:10.1063/1.1684310

出版商:AIP    

年代:1970

数据来源: AIP