Abstract: Embodiments of the present invention relate to apparatus, systems and methods for adding a humidity-controlled system to a thermogravimetric instrument. A humidity-controlled controlled chamber incorporates a housing, a humidifier, a sample chamber, a reference chamber, Peltier devices, humidity and temperature sensors, and gas transmission lines into a single unit. This single unit along with an electronic control unit and mass flow controllers provide a humidity-controlled system designed to control the atmosphere of TGA sample and reference chambers simultaneously. A system comprising an arm, motorized linear actuator an electric control unit, allows a humidity-controlled chamber to be automatically opened and closed, in turn, allowing reference and sample chambers to automatically be accessed.

Abstract: Embodiments of the present invention relate to apparatus, systems and methods for adding a humidity-controlled system to a thermogravimetric instrument. A humidity-controlled chamber incorporates a housing, a humidifier, a sample chamber, a reference chamber, Peltier devices, humidity and temperature sensors, and gas transmission lines into a single unit. This single unit along with an electronic control unit and mass flow controllers provide a humidity-controlled system designed to control the atmosphere of TGA sample and reference chambers simultaneously. A system comprising an arm, motorized linear actuator and electronic control unit, allows a humidity-controlled chamber to be automatically opened and closed, in turn, allowing reference and sample chambers to automatically be accessed.

Abstract: The present invention relates to apparatus, systems, and methods for opening an autosampler sealed sample pan prior to TGA testing. The sealed sample pan comprises a pan, cover, and bail. A notch is formed in the seal sample pan cover. The cover can be opened by applying a concentrated force to the inside of the notch with a punch element integrated into the autosampler. This causes the center disk portion of the cover to be partially sheared and the sealed sample pan to be opened. It also prevents the punch element from touching the sample. A force sensor is used to determine if the cover has been opened. If the cover has been opened, then the sample pan is loaded to the TGA balance. If the cover has not been opened, the autosampler will not load the pan and will automatically move to the next sealed sample pan.

Abstract: A heater controller for allocating heaters to cool a thermal chamber of a scientific instrument evaporates cryogenic liquid to produce a coolant gas. The gas is injected into a chamber to cool a sample disposal therein. The controller allocates low-capacity heaters in compliance with IEC guidelines to prevent problems generally associated with switching of large current loads, such as heaters. In one embodiment, heaters are activated so as to avoid jump discontinuities by effectively averaging the power delivered by the heaters. A second embodiment reduces complexity by essentially disregarding the problem of the jump discontinuity. A third embodiment groups the heaters according to a binary grouping scheme. The heater controller of the present invention can be used to control temperature according to a user supplied temperature profile.

Abstract: A Differential Scanning Calorimeter (DSC) which has constant calorimetric sensitivity over its entire range of operating temperatures from -200.degree. C. to 540.degree. C. The DSC sensor consists of a pair of thin-film Resistance Temperature Detectors (RTDs) which are used to sense the temperature of a sample and the temperature difference between the sample and an inert reference. The RTDs are supplied with an excitation current which varies according to the temperature of the reference to achieve constant calorimetric sensitivity, independent of the operating temperature.

Abstract: A dynamic and thermal mechanical analyzer incorporating a slide driven vertically in an air bearing guidance system with a large displacement capacity, very low friction and low mass. The position of the slide is measured by digitizing and interpolating two quadrature output signals generated by an optical encoder with very high spatial resolution and a long stroke. A force is applied to the slide using a linear permanent magnet motor with high force, high force linearity and low sensitivity to temperature variations. Position signals derived from the digitized and interpolated quadrature output signals are analyzed as a function of the applied force to calculate viscoelastic properties of a sample of material.

Abstract: A parallel plate or single surface dielectric analyzer is disclosed including: a distance sensor for accurately measuring the varying distance between the electrodes, such as a linear voltage differential transformer (LVDT), and apparatus responsive to the distance sensor for positioning the electrodes; a force transducer for measuring the applied force on the sample and apparatus responsive to the force transducer to give a desired force by varying the electrode spacing; disposable electrodes made using thick film technology composed of a ceramic substrate with a conductor adhered to its surface; and a temperature sensor built into one of the electrodes such as a platinum ring adhered to the surface of one of the electrodes and apparatus to measure the resistance across the platinum ring.

Abstract: A parallel plate dielectric analyzer is disclosed including:(a) a distance sensor for accurately measuring the varying distance between the electrodes, such as a linear voltage differential transformer (LVDT), and means responsive to the distance sensor for positioning the electrodes;(b) a force transducer for measuring the applied force on the sample and means responsive to the force transducer to give a desired force by varying the electrode spacing;(c) disposable electrodes made using thick film technology composed of a ceramic substrate with a conductor adhered to its surface; and(d) a temperature sensor built into one of the electrodes such as a platinum ring adhered to the surface of one of the electrodes and means to measure the resistance across the platinum ring.

Abstract: A parallel plate dielectric analyzer is disclosed including: a distance sensor for accurately measuring the varying distance between the electrodes, such as a linear voltage differential transformer (LVDT), and a motor responsive to the distance sensor for positioning the electrodes; a force transducer for measuring the applied force on the sample and where the motor responsive to the distance sensor is also responsive to the force transducer to give a desired force by varying the electrode spacing; disposable electrodes made using thick film technology composed of a ceramic substrate with a conductor adhered to its surface; and a temperature sensor built into one of the electrodes such as a platinum ring adhered to the surface of one of the electrodes and means to measure the resistance across the platinum ring.

Abstract: An apparatus for handling and moving a plurality of objects such as containers each holding a sample to be analyzed by an analytical instrument contains the following:a. a robotic arm assembly capable of vertical, horizontal and rotational movement;b. gripper mechanism for holding objects attach to the arm of the assembly;c. stepper motors for driving the robotic arm assembly;d. a power source that drives the stepper motors electrically coupled to the motors;e. a sensing system with a feedback loop that monitors the movement of arm assembly, the objects being manipulated by the arm assembly and the force applied to the objects by the gripper mechanism;f. a computer electrically interfaced with the linear stepper motors, the power means and the sensing system with the feedback loop andg. a means for providing operating data input to the computer;operating data is provided to the computer for operation of the autosampler and the autosampler moves the object as directed.

Abstract: Apparatus and method for NO.sub.x analysis in which a sample gas is introduced into a sample cell and mixed with oxygen to induce conversion of NO to NO.sub.2. After a given time, prior to complete conversion of NO to NO.sub.2, the absorbance and the time rate of change of absorbance is measured. The time rate of change of absorbance is indicative of the initial NO concentration in the sample gas; and the sum of the absorbance and the time rate of change of absorbance is indicative of the initial NO.sub.x concentration in the gas. A better indication of the initial NO.sub.x concentration can be obtained from the sum of the absorbance and the square root of the time rate of change of absorbance.