Sampling containers for

Compare the common sample containers for UV-VIS work, IR work, and atomic absorption work State the importance of the wavelength of maximum absorbance,... 

Figure 2.5 Sample container for normal bore high pressure NMR probe.

Arzi E, Sandor E (1983) A variable temperature sample container for low temperature neutron powder diffraction. J Appl Crystallogr 16 449 52... 

A new detergent, Triton-101, in association with p-xylene is used for the suspension of 10 ml. of water with a Y value of approximately 0.5 nCi/liter. The application of a new instrumental technique with three photomultipliers decreases further the Y value of both mixtures. A Teflon cylinder with a volume of 250-300 ml. is used as sample container for low level counting with a Y value of approximately 0.2 nCi/liter. Selected results of samples collected during 1967 are reported, and the radiation dose to the population of the United States from tritium is estimated to be approximately 0.2 mrem./year. 

Sample containers for dry weight determination (VOA vials or 2-ounce jars) with labels... 

Sample containers for surface soil sampling precleaned jars and lids... 

Sample containers for subsurface soil sampling stainless steel or brass core barrel liners 6 inches in length with plastic caps... 

Homogenization is a technique designed to enhance the sampling point representativeness. We use homogenization to make certain that a sample truly represents the properties of soil at a given sampling point and that a subsample taken from a sample container for analysis represents the true characteristics of the soil in the container. 

Fill sample containers for all remaining organic analysis, label them, and place in resealing bags inside coolers with ice. 

S) Ehmann, W. D., and D. M. McKown Heat-Sealed Polyethylene Sample Containers for Neutron Activation Analysis. Anal. Chem. 40, 1758 (1968). 

L.F. Whiting, M.S. LaBean, S.S. Eadie, Evolution of A Capillary Tube Sample Container for Differential Scanning Calorimetry, Thermochim. Acta, 136 (1988) 231. 

For our system we chose the simplest approach — a fast sample conduit with quick quench into an evacuated sample container. For temperature measurements we used a similar probe outfitted with platinum/6% rhodium-platinum/30% rhodium thermocouple. For pressure measurements the same general type probe mentioned was employed but without extracting samples. This probe had one hole opening perpendicular to the longitudinal axis of the probe such that when inserted into the reactor it could be rotated 360°. In this manner the pressures were read from a precision pressure gauge with the opening facing 0°, 90°, 180°, and 270° relative to the direction of flow in the reactor. 

If b+ and b- are of different sign [e.g., H, V) there is a small coherent cross section and a large incoherent cross section. For this reason vanadium is used as a ccilibrant in incoherent scattering cross-section measurements (see below) and as a sample container (for polycrystaUine materials) for many of the experiments described below so that unwanted peaks are not introduced into the diffraction pattern. On the other hand, if an element has one isotope of zero nuclear spin in large abundance the scattering is almost entirely coherent [e.g., 0, Fe). 

Fig. 3.6. Sample containers for continuous ultrasound-assisted leaching. (A) One-piece container. (B) Dismountable container. (Reproduced with permission of Elsevier.)...

The initial screen uses both DSC and DTA dynamic heating method tests to compensate for some of the problems inherent in each test. The DSC test is fast, simple, sensitive, and quantitative. It requires only a small amount of sample. The small sample size, however, can be a problem with some samples, such as distillation residues, because of a lack of sample homogeneity. Also, the only inexpensive sample containers for DSC are aluminum or stainless steel. The containers can sometimes cause problems because of chemical reactions between the sample and pan. The DTA test addresses both of these problems. It uses a 2-5 g sample and the containers are glass. Its disadvantages are that it lacks the sensitivity of the DSC and that it is not quantitative. 

Instruments for measuring the absorption of ultraviolet. visible, and near-infrared radiation are intide up ol one or more (I) sources, (2) wavelength selectors, (3) sample containers. (4) radiation transducers, and (.5) signal processors and readout devices. The design and peifoi mance of components (2). f4). and (5) were described in considerable tletail in Oiapier 7 and thus arc not discussed further here. We will, however, consider briefly the characteristics of sources and sample containers for the region of l9l) to nm. 

Information regarding the corrosivity of the various streams should be supplied. If an operator is provided with a new type of sample container, for example, there should be information which tells him whether the material is safe. 

Sample containers and glassware As discussed earlier, when cleaning sample containers for reuse, much care should be taken. The procedure should not be likely to introduce either contamination or the analyte into the analysis. Therefore when cleaning containers for analysis of volatile organic compound, for example, it would be foolish to use organic solvents as this could introduce the same compound that the method would be measuring. 

Transfer the required volumes into the reaction flasks for phosphate determination or into sample containers for the flow-analyser. 

Flame the open neck of the bottle or sample container for a couple of seconds and immediately pour at least 250 mL into the top of a membrane filter unit. 

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