Freezer milling

Root powdering and demineralization. Sixty-five frozen and pulp-free tooth roots were ground in a Waring blender and powdered under liquid nitrogen in a freezer mill (Spex, Edison NJ, USA). The sieved powder (< 450 pm) was demineralized in dialysis bags in 0.5 M EDTA, pH 7.4, at 4°C with regular replacement of the solution. Demineralization was continued until no further calcium release could be detected by atomic absorption spectrometry. 

Freezer mill SPEX CertiPrep (Metuchen, NJ) Y N Y N Y Yu and Cohen, 2003... 

A variation of the Bead Beater is the freezer mill, which uses small magnetic bars rather than beads to pulverize the sample. Cooling is provided by immersing the sample chambers in a liquid nitrogen bath. The freezer mill is intended for larger samples (>500 mg) but may be customized for smaller samples. Both the freezer mill and the Bead Beater require that the sample be placed in secondary containers, which may or may not be disposable. Disposable secondary containers offer the very attractive advantage of reduced time and effort for cleaning. 

Milling soft flexible Freezer mills Impact grinding using a steel... 

M SPEX Certiprep Mixer Mill, 2.0x0.5 in. stainless steel vial, 0.150 in. Pall. t SPEX Certiprep freezer mill, -196°C, 30min aldehyde NaH 10 1 mol. 

Ethylene glycol dimethacrylate (EGDMA, 16 mmol), methyl methacrylate (MMA, 8 mmol), toluene (4 mL), Wako V-65 (0.044 mmol), pinacolyl methylphosphonate (0.029 mmol), and 9 (0.029 mmol) were placed into a disposable glass reaction flask equipped with a stir bar. The solution was subjected to three freeze/pump/thaw cycles with argon backfil]. The solution was placed into an oil bath heated to 60 C for 18 h before the solvent and unreacted monomer were removed by heating to 60 "C while under vacuum (0.5 torr) for 4 h. The salmon-colored polymer was ground with a freezer mill to a fine powder. 

Liquid nitrogen pulverizer (Freezer-Mill, Spex)... 

Seven of the artifacts from the La Scola site were analyzed by ICP-MS. Samples were ultrasonically cleaned and dried, and then pulverized at liquid nitrogen temperatures using a SPEX 6700 freezer mill. 100 mg of the powdered sample were mixed with 0.2 mL aqua regia and 2.5 mL hydrofluoric acid and dissolved in a Parr acid digestion bomb at 120 °C for 2 hours. Samples were then diluted to a total volume of250 ml so that elements of interest would be present at concentrations of 500 ppb or less. 

To determine Irganox 1076, CAO-40, and Santonax R antioxidants in polyethylene the additives were extracted from the polymer by grinding them in a freezer mill then extracting with diethyl ether in a Soxhlet extractor for two days. The ether was then evaporated off and the residues dissolved in 25 cm of 1% by volume of isopropanol in hexane. Using the chromatographic system of a 1% isopropanol in hexane solvent and Corasil II adsorbent (surface area 14 2 mV ) and the conditions outlined below the amount of hindered phenolic antioxidant in the ether extract of the polymer was determined. Column 1000 inm x 2.1 mm, i.d. packing 37-50 u Corasil II (activated at 110°C) carrier 1% (v/v) iso-propanol in hexane flow rate - 0.95 ml/min. 

The PP pellets were ground into a powder using a SPEX CertiPrep Freezer Mill (Metuchen, NJ). The pellets were precooled for 5 min followed by three 2min grinding cycles at lOHz. Between each cycle the sample was cooled for a Imin interval. Nanocomposites were created by dry blending the PP powder with a given ratio of MWNTs (0.25, 0.50, 1 and 3 wt%). 

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