摘要:

A large area focusing x‐ray collector constructed for a sounding rocket is described. The instrument consists of nested reflecting plates that are curved slightly in one dimension to form a set of parabolas with a common focus. An array of plates such as the one in the sounding rocket focuses a parallel beam of x‐rays to a line. The reflecting surfaces are commercial float glass with an evaporated metallic coating such as gold or nickel. With a gold coating the effective area of the rocket collector is about 250 cm2for 0.3 keV x rays and about 150 cm2at 1.2 keV. Its angular resolution is a few arc minutes and field of view is about ±0.75° (full width at half maximum). The collector performed successfully during a sounding rocket flight.

ISSN:0034-6748    

DOI:10.1063/1.1686178

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A system is described for recording the envelope of electron spin echoes and for obtaining the superhyperfine splitting of the electron resonance interval from the form of the envelope. The envelope modulation property on which this system depends is summarized briefly, the microwave system and logic systems used to record the envelope are described, and the problems encountered in making a Fourier transform of the envelope in order to derive the superhyperfine frequencies are discussed. The system was set up in order to make measurements on unoriented glass‐like samples. Some results obtained with samples of this type are shown.

ISSN:0034-6748    

DOI:10.1063/1.1686179

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A system that is capable of dielectric permittivity measurements in liquids and solids in the temperature range 10–300 K and at pressures to 11 kilobar is described. A brief discussion of some experimental data and sources of error is included.

ISSN:0034-6748    

DOI:10.1063/1.1686180

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A new type of heat‐pipe oven has been developed that uses centrifugal force as a return mechanism for the condensed vapors in contrast to capillary return forces for the conventional heat‐pipe oven. Since this new oven is no longer limited to materials that wet wicks, it can be used to containanymaterial that does not react with the walls of the containing vessel. We describe the operation of this oven with sodium and InI even when the InI is solid. Spectroscopic and laser applications of the ``rotating'' heat‐pipe oven are discussed.

ISSN:0034-6748    

DOI:10.1063/1.1686181

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A compact self‐contained linear displacement micropositioner is described which is ideal for very precise positioning along a single axis. The micropositioner has a useful range of about 1.8mm and a resetability of about 0.025&mgr;. Backlash in the device is nil.

ISSN:0034-6748    

DOI:10.1063/1.1686182

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Presented in detail are the construction and relevant properties of a high‐pass wide band filter with a low frequency cutoff of several kilohertz and a high frequency cutoff of about 1 GHz to be used with 50 &OHgr; characteristic impedance systems. The application to absorption spectrophotometry makes it possible to bring small transient signals on very high levels of analyzing light automatically on the screen of a fast oscilloscope with negligible offset at high gain settings.

ISSN:0034-6748    

DOI:10.1063/1.1686183

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Construction techniques are described for a thermistor bimetal thermocouple electrode sensitive to thermal changes at the single electrode during scanning electrochemical experiments in liquid solutions. Incorporation of a thermocouple in this device permits caloric standardization of (DTA) thermogram peak areas from the known bimetal Peltier effect enthalpy change for passage of a known charge across the couple.

ISSN:0034-6748    

DOI:10.1063/1.1686184

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

By a direct examination of chip formation while machining, a considerable amount of data pertinent to the development of the theory of metal cutting can be obtained. However, the microscopically heterogeneous plastic flow involved in the process calls for high magnification observations. To facilitate this, a new cutting stage has been designed and built to carry out metal cutting studies within a scanning electron microscope. Permanent records of the dynamic cutting operations are then obtained by videotaping the experimental results. This paper describes the stage designed and briefly summarizes the results obtained.

ISSN:0034-6748    

DOI:10.1063/1.1686185

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

The physical characteristics of a substrate are very important in determining the structure of any thin film of an evaporated material which is deposited upon it. In particular, the substrate temperature is very influential in determining whether the material condenses in the form of a continuous film or distinct, isolated particles. For this purpose, a heatable substrate which is simple, inexpensive, reusable, and capable of temperatures up to 350°C is described here.

ISSN:0034-6748    

DOI:10.1063/1.1686186

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A rotating sample magnetometer capable of measuring the relative room temperature magnetic susceptibilities of two 1 g samples with a reproducibility of &Dgr;&khgr;/&khgr;=0.02 is described. The sensitivity of the instrument is &Dgr;&khgr;=± 3 × 10−9, or ∼ 1% of the volume susceptibility of a typical diamagnetic solid. The magnetometer signal waveform is electronically processed by either a commercial signal correlator or by a gated double integrator of our own design.

ISSN:0034-6748    

DOI:10.1063/1.1686187

出版商:AIP    

年代:1973

数据来源: AIP