Sample platform

FIGURE 9.16 A photograph looking inside the graph ite cylinder. The sample platform is visible. 

If the refractometer uses a temperature-controlled water bath, ensure that the temperature is set properly and the pumps are circulating the temperature-controlled water through the sampling platform of the refractometer. 

Using the NOAA ARL air-mass trajectory model, the WATOX researchers stratified volume-weighted averages of precipitation composition by compass sector. The results of these stratifications for excess S0 (Figure 6) showed that Bermuda was an ideal sampling platform for air that, at times, was directly impacted by anthropogenic tical uncertainties. standard error of... 

Sediment cores were taken in the accumulation area of the dams during the winter of 2004-2005 and the summer of 2005. A small boat was be used and during the summer and during winter time the ice was used as a sampling platform. The sediments were cores with a diameter of 31.16 or 55.39 cm. and were sliced in 1 cm. The maximum possible core depth was generally around 35 cm corresponding to the time of construction. 

Figure 5. Diagram of the view cell, (a - quartz windows, b -magnetic stir bar, c - wire mesh flapper, d - sample platform, e - sampling ports).

Fig. 6.4. One of the first typical point-contact configurations. The apparatus is mounted in a vacuum can suspended in a superinsulated Dewar filled with liquid He. Shown (insert) are the (1) vacuum can flange, (2) stainless steel (ss) support structure, (3) differential micrometer, (4) ss gear, (5) pinion rod, (6) spindle, (7) piezoelectric transducers, (8) electrode holder, (9) tip, (10) sample cell, (11) sample platform, (12) coarse sample positioning screw, and (13) coarse sample positioning screw to set sample-tip gap [modified from ref. 6.12]...

In the course of such investigations, workers in this area learned to what extremes they had to go to ensure that their sampHng would not be contaminated by material emanating from the research vessel itself. Special sampling platforms had to be built [ 129], and extreme precautions used in sample taking and handling [130]. This last reference is to work which is certainly a milestone in the field I do not expect to see it improved upon unless or until someone thinks of an exceedingly clever way to sample this material. 

The next generation of solid supports in conjunction with MALDI-TOF analysis of nucleic acids is the transformation to a chip format, in which oligonucleotides or PCR products are covalently attached to a silicon wafer and all subsequent biochemical reactions and the ion exchange are performed on the chip surface [14, 15], This is the next enhancement of the SpectroCHIP , adding to the universal sample platform (as described above) customised versions for specialised applications. 

Drying filter paper samples Platform with filter pap>er samples were carefully moved into the vacuum drying oven, at room temperature for 1 hour. After drying, samples were stored into vacuum packing bags immediately and marked with different concentrations. 

Collection of samples for organic component analysis has a number of special difficulties. The sampling platform (i.e., the ship) is a considerable source of organic material, notably hydrocarbons from fuel and lubricating oil residues and CFCs/halons from refrigeration and fire-fighting equipment. Considerable attention must therefore be paid to sample design such that the sampler can be deployed, retrieved, and the sample processed without exposure to external contaminants. 

Figure 4.3 is a simple diagram of a typical vertical design TMA instrument. Almost all TMA instruments have similar components a sample platform surrounded by a furnace (for controlled heating and cooling), a sample probe (one end of which touches the sample while the other end is connected to the... 

The sample temperature is measured with a thermocouple, located in close proximity to the sample. The sample platform and the probe are made from a material such as quartz, which has a low, reproducible, and accurately known coefficient of thermal expansion and also has low thermal conductivity to isolate the LVDT from the temperature changes in the furnace. 

Many different versions of test equipment exist today. They all basically operate on the same principle. Figure 2-47 illustrates one such typical commercially available testing machine. It consists of a cast aluminum base, a slotted vertical guide tube, a round-nose striker and striker holder, an 8-lb weight, a die and die support, and a sample platform. The sample platform is used to position a sheet of desired thickness for impact testing. The die is removable from the base in order that the actual parts of complex shapes can be placed onto the base and impact tested. 

The polymer to be tested is applied to a flat steel plate in a defined layer thickness and dried. With the aid of an electric motor, the sample platform within the test chamber is moved against the piston and then away again in the opposite direction after contact. The shortest contact time that can be set is 0.01 s. The piston is connected to a piezoelectric force transducer. Variable parameters are the piston area, contact force, contact time and approach speed of the tack experiment The instrument allows measurements from -50 °C to 200 °C. This method also allows basic studies with variation of other key parameters, such as separation speed, surface tension of the test piston, and composition of the adhesive layer [64, 65]. 

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