User Instructions - KERN YDB-03 Mode D'emploi

9 User Instructions

To form a reproducible mean value several density measurement are necessary
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Remove fat from solvent-resistant sample / sinker / glass beaker.
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Regularly clean sample dishes/ sinker/glass beaker, do not touch immersed part
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with your hands
Dry sample/ sinker/pincers after each measurement.
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Adjust sample size to sample dish (ideal sample size > 5 g).
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Only use distilled water.
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When immersing for the first time, lightly shake sample dishes and sinker, in order
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to dissolve air bubbles.
Always ensure that, when re-immersing into the liquid no additional bubbles
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adhere; it is better to use pincers to place the sample.
Remove firmly adherent air bubbles with a fine brush or a similar tool.
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To avoid adherent air bubbles smoothen samples with rough surface.
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Take care that no water drips onto the upper sample dish when weighing with the
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help of pincers.
In order to reduce the surface tension of water and the friction of the liquid on the
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wire, add three drops of a common detergent (washing-up liquid) to the aid liquid
(density modification of dist. water occurring due to the addition of tensides can
be ignored).
Oval samples can be held more easily with pincers when you cut grooves into
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them.
The density of porous solids may only be determined approximately. Buoyancy
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errors occur when not all the air is eliminated from the pores during immersion in
the aid fluid.
To avoid great vibrations of the balance, place sample carefully.
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Avoid static charge, e. g. dry sinker with cotton cloth only.
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If the density of your solid only deviates slightly from that of distilled water, ethanol
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may be used as aid liquid. However, check beforehand whether the sample is
solvent-proof. In addition you must observe the applicable safety regulations
when working with ethanol.
To avoid corrosion, don't leave the density set immersed in liquid for a long time.
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74 YDB-03-BA-e-1410