A hand and foot contamination monitor is a health physics instrument to provide detection and measurement of beta-gamma contamination on the palm of each hand and on the bottom surface of both feet/shoes. There are four channels of detection for two hands and two feet. Four G-M detectors have been used in a single unit to cover the whole area of hand and feet. A regulated high voltage DC power supply (900 V) has been designed using the PIC12F675 microcontroller to operate the pancake Geiger-Müller detectors. The reading is displayed on a linearly scaled 0-100 Bq/cm 2 analog panel meter. The monitor detects beta-gamma radiation emitted by radioactive materials, and if the detected value exceeds a preset level, the monitor sounds an alarm and displays a reading in the respective panel meter. Indicator lamps are used to show the status of contamination. The performance of the system has been tested by using pulse generator and by flat surface radioactive calibration sources. Electronic linearity, detection efficiency, response to the contamination, calibration factor and percentage of error has been measured. Test results were satisfactory and the present system can be used instead of similar imported instruments.
Critical aggregation concentration (CAC) is a well-known parameter used to study the interactions between constituents in an aqueous mixture containing surfactant molecules. In this study, we have studied the effect of Na-based salts on CAC of aqueous binary mixture of neutral polymer, polyethylene glycol (PEG) and anionic surfactant, sodium dodecyl sulfate (SDS) using viscometric method. To estimate CAC, we have applied Jiang model to the measured viscosity data. From the estimated results, we observe that the value of CAC decreases with the increase of salt molecules in the mixtures. This behavior confirms that the presence of salt molecules favors the binding of SDS molecule to the PEG chain. Bangladesh Journal of Physics, 27(2), 39-48, December 2020
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.