摘要:

A safe superfluid‐tight pressure cell in which crystals of helium are grown has been developed. Incorporated in the cell are three unique devices, two of which, a room temperature pump‐out valve and a rupture disc, are described in this paper.

ISSN:0034-6748    

DOI:10.1063/1.1686406

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A simple device is described by means of which one can read accurate numerical values from the minuscule data plots which are published in scientific journals.

ISSN:0034-6748    

DOI:10.1063/1.1686407

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A method is described which improves the signal‐to‐noise ratio in soft x‐ray appearance potential spectroscopy (SXAPS). The incoming photon beam is filtered ahead of the detector by means of thin metallic foils or organic films, resulting in reduction of very low energy photons which produce unwanted noise in the detector. A specific example is given of the use of a 6.3 &mgr; aluminum foil filter in the study of samarium M spectra.

ISSN:0034-6748    

DOI:10.1063/1.1686408

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

An alternative method of measuring soft x‐ray appearance potential spectra is presented. In this method no modulation, tuned tank, or lock‐in amplifier are used. Rather, the dc current induced in a simple Park‐Houston type detector is measured and digitized, and the data are placed on paper tape for computer processing and differentiation. The computer differentiated spectra compare favorably with spectra obtained by modulation technique.

ISSN:0034-6748    

DOI:10.1063/1.1686409

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A solid state device to compensate the NMR double resonance beat signal is described. A beat signal reduction of a factor greater than 102has been reached by using a single coil NMR spectrometer. The compensating effect in a tickling experiment on the AB spectrum of 2‐bromo‐5‐chlorothiophene is shown.

ISSN:0034-6748    

DOI:10.1063/1.1686410

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

This paper describes a circuit which can be used to control the sweep of an electromagnet between preset field limits and provide sychronizing pulses for a signal averager. Two operating modes are provided: manual and automatic. In the automatic mode the field sweeps continue indefinitely between the two preset limits. In the manual mode, the sweep is terminated when a field limit is reached. The controller requires an input voltage proportional to the magnetic field which can be easily obtained from a Hall probe.

ISSN:0034-6748    

DOI:10.1063/1.1686411

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A thermal gravimetric apparatus is described that permits accurate weight determinations in a wide variety of atmospheres at temperatures from 50 to 1700 °C. The unique features of the apparatus are its versatility, ease of operation, high accuracy, durability, and low cost. The design can be used with either programmed heating rates or for high‐temperature isothermal kinetic studies.

ISSN:0034-6748    

DOI:10.1063/1.1686412

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

Electron transmission resonances observed using a retarded energy modulation technique are used to calibrate the electron energy scale for an optical excitation apparatus.

ISSN:0034-6748    

DOI:10.1063/1.1686413

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A latching solenoid valvue, designed for the protection of vacuum systems, is described. In case of power failure, the latching mechanism is released by the action of a charged capacitor and the valve seals off the main part of the system. An air vent is incorporated in the valve.

ISSN:0034-6748    

DOI:10.1063/1.1686414

出版商:AIP    

年代:1973

数据来源: AIP

摘要:

A symmetric rf‐biased point‐contact superconducting quantum interference device, which can be adjusted while in operation at low temperatures, is described. The device retains the inherent stability and other features of the symmetric rf‐biased SQUID while increasing its flexibility, reliability, and even convenience with a simple adjustment feature.

ISSN:0034-6748    

DOI:10.1063/1.1686415

出版商:AIP    

年代:1973

数据来源: AIP