Gemini VII 2390 Surface Area Analyzer
The secret of Gemini’s unique capabilities lies in the innovative use of sample and balance tubes. These tubes are identical in every aspect, including their thermal environment. The sample and reference reservoirs, like their associated tubes, are physically identical and are initially charged to the same pressure. During an analysis, differential pressure between reservoirs is monitored. This common mode technique assures that any differential pressure is solely due to adsorption by the sample and not to factors that lead to variations in free space during an analysis.
- The Windows version includes easy-to-follow installation videos and system verification tests to ensure optimum performance and reliability. How-to videos provide on-screen instruction on instrument operation.
- The patented twin-tube design negates free-space errors introduced by thermal gradient variations or by initial mis-measurement of free space
- Permits low surface area measurements without requiring krypton by essentially eliminating free-space error, the limiting factor in typical static volumetric systems.
- Accelerates delivery of the analysis gas because sample uptake controls the rate at which the gas is delivered to the sample. This results in a surface area analyzer that is as fast as the physics of adsorption allows
- The use of a servo valve to control the rate of gas flow into the sample tube assures accurate attainment of target pressures without pressure overshoot
- Three choices of software control: embedded software with a keypad enabling the Gemini VII to be operated without an external PC, Windows XP or Vista operating system, or the Gemini VII confirm™ 21 CFR Part 11 option.
- Low Cost
- System verification tests
- Fully automatic operation
- High throughput – up to four Geminis can be operated with single computer
- Capable of measuring low surface area materials
- Keypad- or computer-operated with Windows-driven software
- Choice of analysis mode (scan or equilibrate)
- No pressure overshoot
- Common mode rejection of free-space error effects
- No thermal-diffusion errors
- Optional stainless-steel Dewars
- 21 CFR Part 11 software option
- IQ/OQ Validation service (optional)
Three Model Options:
Gemini VII 2390a
Ideal for rapid and accurate surface area determinations by single-point and multipoint BET and Langmuir methods. In addition, provides standard methods for total pore volume, micropore analysis by the t-method, and much more. Included is the capability to determine statistical thickness surface area (STSA) of carbon blacks. (Refer to ASTM D 6556, ASTM D 3765, ISO/DIS 18852.2, or ISO/CD 4652-2/3.)
Gemini VII 2390p
Provides additional precision with the addition of a saturation pressure (P0) tube that allows the system to monitor the saturation pressure of the adsorptive on a continuous basis during an analysis. This design feature permits a rapid measurement of the adsorption isotherm to near-saturation, as well as determination of pore size distribution.
Gemini VII 2390t
Has all the ability of the 2390p, including a P0 tube, with the addition of a larger Dewar and longer sample tubes for extended analyses. This provides the additional capability to measure the total adsorption-desorption process. With this data set, one can perform a BJH or Dollimore-Heal pore size distribution using up to 1000 data points.
MicroActive Interactive Data Analysis Software
Micromeritics’ innovative MicroActive software allows users to interactively evaluate isotherm data from Micromeritics ASAP, TriStar, and Gemini gas adsorption instruments. Users can easily include or exclude data, fitting the desired range of experimentally acquired data points using interactive, movable calculation bars. Isotherms can be viewed on either a linear or logarithmic scale and available to the user under each calculation model. No need to generate reports to review results – now see it graphically and interactively on screen.