Abstract: Water activity measurement systems and methods for determining water activity of material samples in a test environment under controlled temperature and pressure conditions. The gas pressure in a test chamber is reduced or held constant while sample temperature is simultaneously tracked. The water activity of the sample can be determined by detecting the boiling point of the sample, at reduced pressure, over time, and calculating water activity using the atmospheric pressure and the saturation vapor pressure at the boiling temperature. The boiling point can be determined by observing an inflection point in the sample temperature over time, and the pressure and temperature at the onset of boiling can be determined at an intersection of trend lines extending from substantially linear intervals of temperature recordings over time.
Abstract: A pressure indicator: a body having a pressure chamber which has an inlet for communication with a fluid; a resilient diaphragm having a periphery sealed against the body and having one side thereof exposed to the fluid within the chamber; an indicating arm having an inner end which is integrally formed with the other side of the diaphragm and an outer end arm which is adjacent to a scale, the arrangement being such that pressure of the fluid within the chamber causes resilient deformation of the diaphragm which in turn causes the outer end of the arm to move relative to the scale thereby indicating the pressure of the fluid in the chamber.
Abstract: A method for determining parameters for the viscosity or temperature of a brake fluid of a vehicle by way of a predetermined pressure build-up within time limits in at least one defined section of a brake circuit and for detecting a pressure in the said section and/or a time which is required for the build-up of the said pressure.
Type:
Grant
Filed:
March 16, 2000
Date of Patent:
June 7, 2005
Assignee:
Continental Teves AG & Co. oHG
Inventors:
Helmut Fennel, Christine Latarnik, legal representative, Eva-Maria Latarnik, legal representative, Syllva Latarnik, legal representative, Michael Latarnik, deceased
Abstract: A method for monitoring the capability of a source container comprising liquid or solid source material to produce vaporized source material comprises extracting vaporized source material from the source container. The source container is then isolated and a property indicative of the partial pressure of the vaporized source material is then measured as a function of time. The partial pressure (or property indicative thereof) as a function of time is compared with a reference partial pressure as a function of time. An alarm is generated when the difference between the measured property (indicative of partial pressure) as a function of time and the reference property value as a function of time is larger than a predetermined property difference limit. The property can be, for example, overall pressure or source material concentration in the gas phase.
Abstract: A method and device for determining concentration and rate of change of concentration of a gas having ability to act as crystal etchant, such as hydrofluoric acid (HF) or deuterium fluoric acid (DF) gas. A crystal 22 is placed in a chamber and subjected to erosion by the gas. The crystal resonant frequency, changeable during the crystal erosion, is determined and a crystal resonant frequency change is calculated to determine the concentration of the gas. The crystal 22 is preferably an AT-cut quartz crystal. The step of obtaining the crystal resonant frequency is preferably performed in a Colpitts oscillator. The step of calculating the gas concentration, proportional to the change in the crystal resonant frequency, may also encompass calculating a change and rate of change in the gas concentration, and averaging the calculated gas concentration. The crystal 22 is preferably inserted in a crystal holder 20, and mounted on an electronic box 34 which holds the oscillator board.