Salient Characteristics.docx

DSC Specifications

The DSC should meet or exceed the following technical specifications when evaluated as described for each value with no post-test desmearing, deconvolution or other manipulation:

Baseline Linearity (-50°-300°C) <5 W Defined as the average absolute deviation from a best fit linear regression of a baseline scan without any smoothing or blank subtraction applied Baseline Repeatability (-50°-300°C) <5 W Defined as the average standard deviation of at least 10 empty cell baseline scans (data collected at 1°C intervals), opening and closing the lid in between each run Baseline Accuracy (-50°-300°C) ±20 W Defined as the maximum allowable error from the theoretical value (0 W) for any measured baseline value over the temperature range noted Heat Flow Digital Resolution 0.001 W Defined as the smallest measurable difference between two adjacent values Baseline Noise (-50°-300°C) <0.2 W Defined as the average rms noise over the temperature range noted Temperature Range -90°C to 550°C (Mechanical Cooling)

Temperature Accuracy ±0.025°C Defined as the standard deviation of the measured error (at least 10 replicate runs after temperature calibration) of the onset temperature of an indium melting measurement at 10°C/min, removing and replacing the sample in between each run Temperature Precision ±0.002°C Defined as the standard deviation of the measured onset melting temperature of at least 10 indium runs, without disturbing the sample in between each run Temperature Repeatability ±0.025°C Defined as the standard deviation of the measured onset melting temperature of at least 10 indium runs, removing and replacing the sample in between each run Enthalpy Precision ±0.04% Defined as the relative standard deviation of the measured enthalpy of at least 10 indium runs, without disturbing the sample in between each run Enthalpy Repeatability ±0.25% Defined as the relative standard deviation of the measured enthalpy of at least 10 indium runs, removing and replacing the sample in between each run Indium Response Ratio >100 Defined as the height to width ratio of an indium melting peak, 1±0.02 mg sample, 10°C/min, N2 atmosphere, data measured as collected from the instrument with no post-test desmearing, deconvolution or other manipulation

Instrument Features

The DSC should be of the Heat Flux design whereby the sample and reference are measured in the same furnace, on separate stages.

The DSC should employ area temperature detectors directly beneath the sample and reference positions, not platinum resistance thermometers or thermopiles.

The DSC furnace shall be constructed of silver, with platinel heater windings. The benefit of this design is in the uniform thermal environment, and long furnace lifetime.

The DSC should include a third thermocouple, thermally isolated from the sample and reference, to act as an objective reference point for temperature control and Tzero measurements as described below.

The DSC module must provide for the user the ability to replace the DSC cells (sensor, furnace and associated electronics) by simply removing a few screws. This will allow various research groups to have their own DSC cell for use on a single base platform. The user should not be required to manipulate fragile thermocouple leads and/or tensioning springs to replace DSC sensor.

The DSC cell should include integrated, temperature controlled electronics for stable signal processing.

The DSC must include integrated purge gas delivery control accommodating at least two simultaneously installed gases. This capability must be incorporated into the instrument (i.e. shall not be a separate unit) and should not require external tubing to deliver the gas flow from the controlling components to the DSC cell. Purge gas flow rate must be programmable within operating software, and deliverable as a saved signal in the data file. Gas delivery control must also allow for automated switching between the two gases during an experiment.

Purge gas is pre-heated prior to entering the sample chamber and sweeps across sample for optimal purge interaction with sample. By design, all oxygen is purged from "dead spaces" of cell; reliance on diffusion of purge gas is avoided.

The DSC should employ patented Tzero® Heat Flow technology, defined and compliant as described in the section below.

The DSC must include Modulated DSC, defined and compliant as described in section below.

The DSC should include an autosampler which can be configured to accommodate up to 54 samples.

· The reference pans should be configurable to any of the positions in the 54 position tray.

· The autosampler must be capable of loading and unloading both sample and reference pans.

· The autosampler shall accommodate a variety of DSC pan types, including but not limited to: standard, hermetic, open, and high-volume.

· The autosampler must employ auto-lid device, which removes all coverings from the DSC sensor

· The autosampler shall employ mechanical finger-style gripper, not a suction device.

· The autosampler shall incorporate a laser edge-detection system for pan sensing.

· The autosampler shall be controllable through a touch-screen display, or by some other means independent of the controlling computer.

· The autosampler shall not require regular lubrication.

The DSC system must include a touch screen interface for easy controller access and monitoring.

The DSC should communicate with computer/controller through Ethernet BUS as this is an industry and laboratory standard, and allows for maximum flexibility in instrument installation.

Data files contain measured sensor temperature, not calculated temperature. This allows the user to know what temperature the sample is actually at during different heating rate experiments and makes for accurate and precise transition temperatures.

Must have up to five points for temperature calibration.

Tzero® Heat Flow Measurement The DSC must employ Tzero technology (as described in the following patents) for the most accurate measurement of heat flow: US Patents: 6,488,406, 6,431,747 and 6,561,692; Additional Patent Nos. EP 1136802, JP 4074441, 3936846, 3,936,847.

The DSC shall employ a heat-flow equation of no less than four terms. This equation shall be as follows:

The purpose of the four-term heat flow equation is to measure and compensate for various factors within the heat-flow measurement, which provides for superior instrument performance.

Within the four-term heat flow equation, the following must be directly measured and incorporated:

The instrument must also be capable of incorporating a sample-pan contact resistance measurement, which dramatically improves signal resolution.

The DSC must be capable of measuring heat capacity directly, from one experimental run, through the incorporation of the aforementioned equations

Modulated DSC® Supplier must show proof of long-term product viability that is not conflicting with TA Instrument's patents:

6,561,692 “Differential Scanning Calorimeter”, May 13, 2003.

Modulated DSC must be supplied with the following criteria:

· Ability to apply sinusoidal temperature wave to sample: Amplitude of sine wave ± 0.01 to 3C; frequency period from 10 to 200 seconds.

· Must include the ability to perform quasi-isothermal experiments, i.e. holding isothermal with a small temperature modulation.

· The temperature modulation should be strictly periodic to ensure continuous steady-state control and exact experiment reproducibility, random temperature perturbations are not acceptable.

· In order to view the signals real-time, deconvolution of the signals must be done real-time, on board the module using a discrete Fourier Transformation, not after the scan.

· All of the signals above must be collected during one single experiment and stored in one single data file.

· Must be able to view the following signals in real-time during the experiment: Total Heat Flow, Total Heat Capacity, Reversing Heat Capacity, Reversing Heat Flow, Non-Reversing (Kinetic) Heat Flow, Modulated Temperature, Modulated Heat Flow, Heat Flow Phase, Reference Sine Angle, Temperature Amplitude, Heat Flow Amplitude.

· The heat capacity measurements must not require a prior baseline scan that has to be subtracted from the sample scan for quantitative data.

· Must include the ability to measure thermal conductivity of insulators with no hardware modifications to DSC.

Software

The DSC must include operating software, which allows for the instrument to be fully calibrated and verified automatically, without the need for operator presence. Calibrations must include baseline, cell constant, and temperature. Scheduling capabilities must be present, such that these calibrations and/or verifications can be programmed to perform during normal quiescent periods, such as overnight or on weekends.

The data analysis software should be unkeyed, to allow for unlimited installations within one site. The data file format should easily allow sharing/transfer of data files as individual electronic documents, which are readable by the same data analysis package. The data analysis program should also include a .pdf generator, for the efficient export of analyzed plots.

The software must have the ability to support legacy data from previous generation of equipment. These capabilities include the ability to open, analyze, overlay and incorporate reports into the new system.

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