摘要
氧弹量热计法测定不同土壤胡敏酸的热值(能态)表明,不同土壤胡敏酸具有不同的能态。土壤胡敏酸总能态高低与土壤有机质、全氮、胡敏酸含量呈显著正相关。DTA和TG法测定不同土壤胡敏酸的热分解特性表明,不同土壤胡敏酸的DTA、DTG曲线都有共同相似的热效应峰和失重峰。同时表明,与之相对应的焓变(△H)、重量损失百分数(W%),最大重量损失率-(dW/dT)m、活化能(E)、比速率常数(K_0)都有一定差异。红外光谱测定表明,不同温度下,不同胡敏酸热解温度上升到324—338℃时,主要是非核部分脂肪族侧链及氢链结合OH的裂解;当热解温度至444—464℃吋,主要是羧基和芳香核裂解;当热解温室达700℃以上吋,芳香核裂解趋于完全。
Caloric value of humic acid in different soils determined through oxygen-bomb calorimeter method showed that the humic acid in different soils has different energe tic states and the total energetic state of soil humic acid was positively correlated with the soil organic matter, total nitrogen and the amount of soil humic acid. The humic acid pyrolytic properties observed by means of DTA and TG methods in different soils indicated that the humic acid from different soils showed similar heat effect peak and weight loss peak in DTA and DTG curves. Difference was found in its homologous enthalpy change (△H), the percentage of weight loss(W%), the maximum rate of weight loss(dw/dT)m, activation energy(E), and the specific rate constant(k_σ)。 The data determined by infrared spectra indicated that under different temperature, the spectra properties of the samples of different humic acid pyrolysis were alike. When the temperture reached 324—338℃, the fission took place mainly in aliphatic side chain and hydrogen bonded—OH groups in non-nuclear part; when the temperture was raised to 444—464℃, the fission took place chiefly in carboxylic groups and aromatic nucleus; when the temperature went up to 700℃, the fission of aromatic nucleus tended to be completed.
出处
《土壤学报》
CAS
CSCD
北大核心
1990年第2期151-158,共8页
Acta Pedologica Sinica
