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> Balzers union cpd 020/critical point dryer #9459
Balzers union cpd 020/critical point dryer #9459
Cool Stuff from Dr.A's (Quack) Andrews Basement ~DR. A'S WILD~ EQUIPMENT~SHOCKING~WILD STUFF~ DESCRIPTION: BALZERS UNION CPD 020 MICROSCOPY CRITICAL POINT DRYER Compact bench unit
Space saving design with integrated control and supply units.
Minimum consumption of the CO2 .
The top loading system with safety screw-on cover is ideal for fast, easy specimen insertion.
The solenoid high pressure valves are operated from the manual valves.
Approved pressure container with bursting membrane and two other independent safety features guarantee
Damaging turbulences caused by admitting and draining fluids too fast or heating them too quickly are reduced to a minimum through the use of apertures of varying sizes and because the heating parameters are adjustable.
Conveniently arranged control and display elements
Digital temperature and analog pressure
Can be used for better and faster mixing of the transitional fluids (Not for delicate specimens).
Large, safety sight glasses provide excellent viewing of the submerged specimens during the CP process both from above and from the side.
For the most varied applications.
The variable operating parameters allow all commonly used transitional fluids to be used.
Consistent modular design and removable cover panels assure easy access to the individual assemblies.
Botanical specimens (tissue samples, spores, etc. from lower and higher order plants)
Zoological specimens (tissue samples, cell cultures, etc. from animals and humans)
Samples from industrial production (food, etc.)
After drying, the SEM specimens are coated with a metal such as gold, platinum or palladium to make their surfaces electrically conductive.
- Specimen structures can be better preserved by combining critical point drying with fast freezing and freeze substitution [1] [2].
The critical point drying method
Drying water-containing biological specimens in air or under vacuum can drastically alter their structures or even destroy them completely. They must therefore be dried by a gentler method.
One well-known method is "Critical Point Drying".
The surface tension of the water in a specimen at the point at which it changes from the liquid phase to the gaseous phase can destroy a delicate specimen.
By increasing the pressure and temperature of the specimen it is possible to dry it without crossing a phase
This is possible because once the critical point has been passed, the density of the "liquid" and the density of the "gas" are the same. The critical point for water is 228,5 bar and 374 C. However, this high pressure and extreme temperature would normally destroy a biological specimen. For this reason the specimen must first be treated in a suitable transitional fluid such as CO2 whose critical point of 73,8 bar and 31 C is considerably more advantageous.
Main fuse F1 / F2 4 A slow blowing (230 V / 240 V)5 A slow blowing (115 V)
Safety bursting membrane approx. 150 bar
COOLING range, adjustable 2 C to 12 C
HEATING range, adjustable 30 C to 45 C
Cool down time approx. 2.0 C/min.
Heating time NORMAL approx. 3.2 C/min.
Heating time SLOW approx. 0.9 C/min. UNIT POWERS UP AND STIRRER WORKS. SEEMS IN GOOD SHAPE AND DOES NOT SHOW ANY ABUSE OR EXESSIVE WARE.
