摘要:

A procedure is given for determining the diffusion constantDwhen the rate of uptake (or loss) of the diffusing material can be measured at any one time.

ISSN:0021-8979    

DOI:10.1063/1.326708

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

An anomalous photocurrent observed in reverse‐biased SnO2‐Si heterojunctions, obtained by spraying, is reported. This current becomes voltage independent above a certain reverse voltage value and is much larger than expected from the number of photopairs generated. The anomalous photocurrent occurs above a minimum voltage value and a minimum number of incident photons, these thresholds being constant for each cell. The anomalous photocurrent is generated under the SnO2window, its density being larger under the window edge region.

ISSN:0021-8979    

DOI:10.1063/1.326673

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Thermal sublimation of atomically homogeneous ZnxCd1−xS powders from a single source results in films that are nonuniform in a direction normal to the substrate. This is attributed to initial preferential sublimation of Cd from the charge and is verified by energy dispersive x‐ray analyses of film cross sections and of the charge residue. These results are related to the utility of this technique for forming ZnxCd1−xS films for photovoltaic applications.

ISSN:0021-8979    

DOI:10.1063/1.326674

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The Kerr coefficient of nitrobenzene was measured over the temperature range 285–340 K. To within experimental error, the data indicate that the Kerr coefficient can be expressed as a quadratic function of reciprocal temperature. Fitting the data to this quadratic function yields an equation which can be used to correct the response of a pulse‐voltage measuring system based on the Kerr effect for variations in the ambient temperature.

ISSN:0021-8979    

DOI:10.1063/1.326675

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Boron hydride emits a broad band of yellow light at 2.1 eV when excited optically. The emission is nearly temperature independent from 78 to 300 °K. An external power efficiency of 5×10−3is obtained. The luminescence exhibits fatigue at room temperature. An absorption edge is found above 1.2 eV.

ISSN:0021-8979    

DOI:10.1063/1.326676

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Electron beam damage to thin‐film SiO2was observed with a scanning Auger electron microscope. After a certain degree of electron beam exposure, changes in both the surface topography and chemical composition were investigated. The result suggested that there is a close relationship between the beam damage and the dissipation of incident energy in thin‐film SiO2.

ISSN:0021-8979    

DOI:10.1063/1.326677

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A simple analytical model has been developed which describes the heating of a thin opaque target in air when subjected to irradiation from a high‐power pulse laser. Effects due to the formation of a laser‐supported absorption wave (LSAW) above the target surface are explicitly included in this model. The effective on‐target flux distribution is assumed to be described by a radially expanding Gaussian profile in order to simulate the effects of enhanced coupling dominated by uv emission from the hot expanding LSAW plasma. Target heating inside as well as outside the incident beam‐spot region is described. This model is an improvement over the previous approach [J.E. Robin, Appl. Phys. Lett. 30, 401 (1977)] which employed a radially expanding uniform flux distribution that was based on the assumption of a thermal‐conduction‐dominated enhanced‐coupling mechanism.

ISSN:0021-8979    

DOI:10.1063/1.326678

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

Angular intensities of 1 &mgr;A sr−1have been measured for a gas‐phase field ionization source in an optical column under practical operating conditions. The source, which was differentially pumped and cooled to 77 K, utilized a ⟨110⟩‐oriented iridium emitter and precooled hydrogen gas at 10−2Torr. The ion beam was collimated with an electrostatic lens and detected below an aperture subtending 0.164 msr. A transmitted current of ∼10−10A was measured at voltages corresponding to a field of ?2.2 V/A˚ at the emitter.

ISSN:0021-8979    

DOI:10.1063/1.326679

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

A recent calculation of the thermal efficiency of a solid‐state engine made with a Ni‐Ti alloy (Nitinol) has been criticized with reference to the origin of the work output and the deformation behavior of the material.

ISSN:0021-8979    

DOI:10.1063/1.326680

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

In reply to the comments of Mohamed and Banks, we outline the conditions under which a Ni‐Ti shape‐memory element operates in a solid‐state engine. The expression for the energy output of this element, which was used in the original paper, is derived here, and further aspects of the efficiency formula for this engine are explained.

ISSN:0021-8979    

DOI:10.1063/1.326681

出版商:AIP    

年代:1979

数据来源: AIP