| 摘要 |
<p>Parent patent describes quantitative determination of substance in soln. using a small sample tube of transparent material filled with a free-flowing absorbent in powder form, retained by a constriction in the tube and a permeable support. In this addn., method for estimation of mercuric or sulphide ions in aq. soln. comprises using a sample tube contg. as absorbent a chemically-modified cellulose powder with amino or imino gps., though which a soln. contg. Hg (II) ions is first passed, followed by a soln. contg. dithio-oxamide or sulphide ions. A brown or black zone with sharply-defined boundary is obtd., the length of which is proportion to the conc. of Hg or sulphide ions. Pref. the absorbent is polyethylene imine cellulose, which may be mixed with neutral cellulose powder in wt. ratio up to 1:30.</p> |
