Sample preparation for solid

Sample Preparation for Solid-State NMR. The amount of sample needed for solid-state NMR analysis depends on the size of the rotor used. Between 75 and 100 mg of sample is needed to fill a 4-mm rotor whereas 7-mm rotors require... 

Sample Preparation for Solid Polyethylene Glycols Carefully introduce 25.0 mL of the Phthalic Anhydride Solution into a clean, dry, heat-resistant pressure bottle. Add an accurately weighed amount of the sample, previously melted, equivalent to its expected molecular weight divided by 160 to the bottle because of limited solubility, however, do not use more than 25 g of any sample. Add 25 mL of pyridine, freshly distilled over phthalic anhydride, swirl to effect solution, stopper the bottle, and wrap it securely in a fabric bag. 

Sample Preparation (for solids) Transfer 50 g of the sample, or a quantity of the sample with a known quantity of sulfur dioxide (500 to 1500 pig of S02), to a food processor or blender, if necessary. Add 50 mL of 5% ethanol in water, and briefly grind the mixture, reserving another 50 mL of 5% ethanol in water to rinse the blender jar. Grinding or blending should be continued only until the food is chopped into pieces small enough to pass through the 24/40 joint of a flask (see Fig. 43). 

Sample preparation for solid-state NMR can be as simple as drying and grinding (Kolowith and Berner, 2002). Solid-state soil studies have also used dried extracts of soils, in an attempt to remove paramagnetic ions with reagents such as dithionite (Look-man et ah, 1996 Delgado et aL, 2000), DTPA (diethylenetriamine pentaacetate) (Sutter et... 

The main problems with field analysis are sample preparation for solids and lack of sensitivity for liquids. One option for converting solid matrices (rock, soil, concrete etc.) into solution is to utilise equipment for the preparation of XRF bead samples. Portable versions are available commercially and use lithimn borate fusion at 1000°C to solubilise siliceous and other refractory matrices in a single step, rather than repeated extraction with aggressive and toxic reagents, such as hydrofluoric and/or perchloric acids. The beads can be analysed non-destructively for major components by portable XRF and then dissolved for alpha spectrometry or HazWAC, as required. 

The two most common forms of sample preparation for solids both involve grinding the material to a fine powder and dispersing it in a matrix. Scattering and... 

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