| 摘要 |
<p>A test tube for determining substances in soln. consists of a transparent material filled with an adsorbent. The transparent tube is narrowed on one side, closed on one side, with a liquid-permeable insert placed on narrowing and filled with a dry, powdery and flowable adsorbent. Filling is then compressed with a stamp. corresponding to tube dia., at 0.1-100 (0.5-5 bar). Test tube can be transported without risk of unmixing, stored without excluding air and used without preliminary preparation. In use, there is no overflow. Test tube may be of glass or plastic. Pref. insert is a cellulose acetate fibre stopper. Glass- or polyethylene fibres may also be used. Adsorbent pref. consists of reagent-charged cellulose powder, e.g. diethylaminoethyl cellulose mixed with neutral cellulose powder.</p> |
