Probe sampler

Sample line dispersion can be reduced by introducing several air bubbles between samples and the inter-sample wash, using a so-caUed peddng-probe sampler. In practice, this is most useful for viscous samples such as hlood serum. 

FIGURE 5 Stationary bulk sampling (a) low-volume powder sampler (b) thief/spear probe sampler (c) pneumatic lance sampler [7]. 

Probe-nadel, /. touch needle, -nabme, /. sampling sample, -nebmen, n. sampling, -nebmer, m. sampler. 

Probe-zleben, n. sampling, -zieber, m. sampler. -zinn, n. standard tin. -zylinder, m. trial jar test tube. 

Figure 5. The unmanned plane used to collect and identify aerosolized bacteria in field trials at Dugway Proving Ground, UT. The plane carried a ten-pound payload including a cyclone air sampler and 4-probe fiber optic biosensor.

Porous cups can be used as probes in the monolith and suction can be applied to them to move water out of the soil and into a sample container under unsaturated conditions. Passive samplers that do not involve pressure or vacuum are also available [11]. 

TTie instrument is built around a commercially available autosampler designed by P.S. Analytical Ltd, Kent, UK. This has a helical tray and the probe remains static. All the analytical modules are incorporated in to the upper housing of the sampler system. The unit is compact but it is difficult to maintain and service nevertheless it has been widely accepted as a standard in the UK water industry. 

Interesting are attempts to design dynamic hardness testers with a higher level of automation. Among these, we should mention the Equotip hardness tester manufactured by Proceq of Switzerland and the Sonodur A probe manufactured by Branson-Krautkramer. In the former, the sampler in the shape of a ball of sintered carbide is mounted in a beater weighing 5.5 g, which is also fitted out with a permanent magnet. This enables measurement of the speed of impulse and rebound by proportional current induction in the measuring coil. The quotient of rebound and impulse speed multiplied by 1000 is defined as hardness L (after the name of the method s author—Leeb). The hardness measurement result L can be converted to HKC, Hb or Hv with the aid of tables. 

After centrifugation, the specimens arc placed in a holder specifically designed to woik with a particular instrument. Once loaded, the sample holder is placed onto the carrier transport mechanism of the system, which is referred to as the sampler. The function of the sampler is to bring each specimen into a position where a sample of it can be taken by the aspiration probe, then to transport it further to the unloading area. 

Sampling Probe or automatic sampler Representative sample... 

Thief/spear probe One or more cavities are stamped Thief samplers belong to... 

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