摘要:

A simple method is reported for the deposition of dielectric films using activated reactive evaporation (ARE). This method uses heated tungsten wire as an electron emitter and does not require a magnetic field for stabilizing the plasma, as required in an earlier reported method. The reactive gas pressure during coating is 5×10−4Torr. An x‐ray diffractogram and optical transmission spectra of Bi2O3films deposited at a rate ≊50 A˚/s using this apparatus are also presented.

ISSN:0034-6748    

DOI:10.1063/1.1138676

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A fast, magnetically driven gas valve and its application to pneumatic‐based solid hydrogen pellet injectors are described. The valve, which is equipped with a polyimide stem tip (hard seal) and a 5‐mm‐diam orifice, can open against working pressures up to 140 bar (2000 psi). Other unique features of this design include temperature‐ and radiation‐resistant seals, a programmable output pressure pulse, and repetitive operation in excess of 20 Hz. A prototype valve has been used to propel frozen hydrogen isotope pellets to speeds of up to 1900 m/s.

ISSN:0034-6748    

DOI:10.1063/1.1138677

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A new calorimeter for single intense microwave pulses has been designed and tested. The device was constructed in WR284 rectangular waveguide and was operated at frequencies from 2.5 to 4.3 GHz with a tunable instantaneous bandwidth of approximately 500 MHz. The calorimeter used a single thermistor to measure the energy deposited on a carbon absorber having a microwave power absorbance of 90%. The calorimeter was tested at power levels from 100 to 1000 MW for pulse lengths of 12–6 ns, respectively. The sensitivity of the device was 200–300 mV/J.

ISSN:0034-6748    

DOI:10.1063/1.1138678

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We describe a simple four‐terminal ac bridge designed to be used with sensors of low resistance, such as platinum thermometer at low temperature.

ISSN:0034-6748    

DOI:10.1063/1.1138679

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We describe a small permanent magnet (no dimension exceeds 8 cm) which produces a uniform magnetic field of 2 T in a volume of about 14 mm3. This magnet has been used to orient macromolecular assemblies for light microscopy, x‐ray, and light‐scattering studies.

ISSN:0034-6748    

DOI:10.1063/1.1138680

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

A digital data‐acquisition system has been built to interface two photoelectron spectrometers to a DEC LSI‐11/23 processor.

ISSN:0034-6748    

DOI:10.1063/1.1139199

出版商:AIP    

年代:1986

数据来源: AIP