【摘要】 <正> 氨是中性分子,它在水溶液中主要以NH₃·H₂O形式存在。氮的测定目前国内外大多数使用氨气敏电极,系将待测液中的氨通过透气膜后改变内充液的pH,再用pH电极测定此变化,间接确定氨含量.也有用硝化菌作为生物催化层的（双膜）电极测定氨。但对中性分子氨敏感的中性载体单膜电极尚未见文献报道.我们在合成双臂型方酰胺多齿更多还原

【Abstract】 A novel ammonia selective electrode fabricated by coating a graphite carbon rod with PVC membrane containing new compound of 1,3-N,N-Bis-[2-（9-oxyhydro-1,4,7-trioxy-tri-ethylcne） phenyl] squaric amide （SQDAM） as neutral carrier was described. This electrode exhibited a linear response to the ammonia in the solution within the concentration range 2.5×10^-4～ 1.0×10^-1mol～dm^-3 with a slope of 61mV in alkaline medium. The detection limit was 1.2×10^-4 mol.dm^-3. The selectivity of NH₃ relative to K⁺,F^-were 7.0×10^-2 and 4.0×10^-2 respectively, nonsignificant interference of anion and cation was observed, and the membrane resistance was lower than 10MΩ.更多还原