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Device and method for determining freezing pointsA freezing point method and device (10) are disclosed. The method and device pertain to an inflection point technique for determining the freezing points of mixtures. In both the method and device (10), the mixture is cooled to a point below its anticipated freezing point and then warmed at a substantially linear rate. During the warming process, the rate of increase of temperature of the mixture is monitored by, for example, thermocouple (28) with the thermocouple output signal being amplified and differentiated by a differentiator (42). The rate of increase of temperature data are analyzed and a peak rate of increase of temperature is identified. In the preferred device (10) a computer (22) is utilized to analyze the rate of increase of temperature data following the warming process. Once the maximum rate of increase of temperature is identified, the corresponding temperature of the mixture is located and earmarked as being substantially equal to the freezing point of the mixture. In a preferred device (10), the computer (22), in addition to collecting the temperature and rate of change of temperature data, controls a programmable power supply (14) to provide a predetermined amount of cooling and warming current to thermoelectric modules (56).
Document ID
20080008236
Acquisition Source
Legacy CDMS
Document Type
Other - Patent
Authors
Mathiprakasam, Balakrishnan
Date Acquired
August 24, 2013
Publication Date
July 22, 1986
Subject Category
Fluid Mechanics And Thermodynamics
Report/Patent Number
Patent Application Number: US-PATENT-APPL-SN-534352
Patent Number: US-PATENT-4,601,587
Funding Number(s)
CONTRACT_GRANT: NAS3-22543
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-4,601,587
Patent Application
US-PATENT-APPL-SN-534352
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