Grinding and Homogenization

Fritsch GmbH http //www.fritsch lab.de/englisch/english.htm/ 

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Improvement of the form grinding and homogenizing of solid and coarse materials... 

The sludge was oven-heated at 105 for 2 days, then after a further grinding and homogenization it was passed through a 50-mesh sieve. 

Usually, the first step in recycling PGMs is grinding and homogenizing of the material and subsequently taking appropriate samples for analysis (important as the basis for settling the accounts). Basically, two technical approaches exist to separate the PGM from the substrate ... 

Direct analysis of solid samples is faster as only a minimum of sample preparation is required typical sample preparation steps, such as grinding and homogenization of heterogeneous materials, have to be carried out prior to a sample digestion. 

For fruits and vegetables, mince and homogenize 1 kg of the sample with a mixer together with an appropriate amount of water, if necessary, and weigh 50 g of the sample. For small fruit samples such as citron, kabosu lime and rind, weigh 20-25 g of the sample. For beans, after grinding the sample, weigh 20 g of the sample and add 40 mL of distilled water to swell the sample for 2h. 

Fluorescence determinations are best made on samples of homogeneous particle size, and this is not the normal state of soil. Grinding and carefully sieving soil before analysis can minimize problems associated with particle size heterogeneity. Another approach has been to fuse soil with borate or to dilute it with cellulose or other suitable diluents. Very thin layers of soil may also be prepared and used for quantitative analysis. 

The solubility and homogeneity of the sample are key to accurate analysis. This solubility can be affected by other ingredients in the product to be analyzed. Certain situations may require use of a much smaller sample size to account for solubility issues. Proper steps must be taken to grind or homogenize the sample to... 

The extraction and isolation of three groups of carotenoids of different polarity are described in Basic Protocol 1. A method for prepurifying carotenoids using crystallization is described in Basic Protocol 2. Carotenoids may be purified further by chromatographic techniques (unit F2.3) and characterized (units F2.2 F2.4). Support Protocols 1 and 2 describe the preparation of the sample before extraction. This process consists mainly of removing water from the sample followed by sample grinding or homogenizing. 

The XRF analysis accuracy depends on physical properties of the soil, such as particle size, moisture content, homogeneity, and surface conditions. Drying, grinding, and sieving soil prior to analysis reduce the effects of these physical interferences. 

Modification of zeolites, based on chemisorption of silane or diborane and subsequent hydrolysis of the chemisorbed hydride groups can also be applied for encapsulating gas molecules in zeolites. For example, krypton and xenon can be encapsulated in mordenite combining the modification process with a physical adsorption of the noble gases at moderate pressures and temperatures (e.g. 100 kPa, 300 K). The encapsulates are homogeneous and stable towards acids, mechanical grinding and y-irradiation. By controlling the pore size reduction however, the thermal stability can be controlled. 

The innovative method involves many stages, including grinding and mixing Jerusalem artichoke with fruit pulp. The mixture is homogenized, heated, and packed in sterilized cans. 

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