Методическая разработка по английскому языку для студентов факультета химии и химической технологии " Simple Chemistry" Алматы 2017
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мет. разработка по химии
| Centrifugation and Sedimentation
These processes rely on differences in density. In a medical lab, blood often goes into a centrifuge. A centrifuge is a machine that spins a sample at fairly high rates of speed. Red blood cells are much denser than the watery substance (called plasma, but it's not the plasma state of matter) that makes up blood. As a result of the spinning, the denser phases move outward and the less dense phases move inward, towards the axis of rotation. Then, the red blood cells can be separated from the plasma. Sedimentation is similar, but it happens when particles of different densities have settled within a liquid. If we leave a jar of muddy water to settle, the heaviest particles sink to the bottom first. The lightest particles sink last and form a layer on top of the heavier particles. You may have seen this effect in a bottle of salad dressing. The seasonings sink to the bottom, the water forms a lower layer, and the oil forms an upper layer. We can skim out the separate phases. To return it to a mixture, simply shake it up to disturb the layers. Vocabulary notes process – процесс to rely on – полагаться , надеяться на кого(что)-либо difference – различие density – плотность lab – лаборатория blood – кровь centrifuge – центрифуга machine – машина, механизм to spin – вращаться sample – образец fairly high rate of speed – довольно высокая скорость red blood cells – красные кровяные тельца dense – плотный watery substance – вещество , состоящее из воды state of matter – состояние вещества to make up - составлять as a result – в результате outward – наружу, внешний inward – внутрь, внутренний towards – в направлении к axis – ось rotation – вращение sedimentation – осаждение density – плотность to settle –располагать jar of muddy water – банка с грязной водой to leave – оставлять to sink – тонуть light – свет, светлый, светить жүктеу/скачать 422,31 Kb. Достарыңызбен бөлісу:
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