CHEMISTRY GLOSSARY
supercritical fluid extraction → superkritična fluidna ekstrakcija
Supercritical fluid extractions (SFE) have solvating powers similar to liquid organic solvents, but with higher diffusivities, lower viscosity, and lower surface tension. The main advantages of using supercritical fluids for extractions is that they are inexpensive, contaminant free, and less costly to dispose safely than organic solvents. For non-destructive isolation choose SFE, which is simply the best technology for sensitive raw materials. For these reasons supercritical carbon dioxide (scCO2) is the reagent used to extract caffeine from coffee and tea. Its gaslike behavior allows it to penetrate deep into the green coffee beans, and it dissolves from 97 % to 99 % of the caffeine present.
three way safety bulb → propipeta
Three way safety bulb (pipette filler bulb) is used for pipeting. The attachment is placed over the mouth of the pipet. Squeeze the air valve (A) and the bulb simultaneously to empty the bulb of air. Place the tip of the pipet below the solution's surface in the beaker. Gradually squeeze the suction valve (S) to draw liquid into the pipet. If the level of the solution is not high enough, squeeze the air valve (A) and the bulb again to expel the air from the bulb. Draw up more liquid by squeezing the suction valve (S). When the liquid is above the specified volume, stop squeezing the suction valve (S). Do not remove the bulb from the pipet. Do not allow liquid to enter the pipet bulb.
vanadium → vanadij
Vanadium was discovered by A. M. del Rio (Spain) in 1801 and rediscovered by Nils Sefstrom (Sweden) in 1830. Named after Vanadis, the goddess of beauty in Scandinavian mythology. It is soft, ductile, silvery-white metal. Resistant to corrosion by moisture, air and most acids and alkalis at room temperature. Exposed surfaces form oxide coating. Reacts with concentrated acids. Vanadium is found in the minerals patronite (VS4), vanadinite [Pb5(VO4)3Cl] and carnotite [K2(UO2)2(VO4)2·3H2O]. Pure metal produced by heating with C and Cl to produce VCl3 which is heated with Mg in Ar atmosphere. It is mixed with other metals to make very strong and durable alloys. Vanadium pentoxide (V2O5) is used as a catalyst, dye and fixer-fixer.
Citing this page:
Generalic, Eni. "Bead snowflakes." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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