控释海水植物肥中氮、磷的测定

为评价控释肥的肥效，探讨、建立了相应的氮、磷测定方法。用硫酸作消解剂，消解液可以同时被用来测定氮、磷。钼锑抗坏血酸络合物作为显色剂，用紫外可见分光光度计测定磷的浓度；用改良式微量凯氏定氮蒸馏滴定法测定氮的含量。该方法灵敏、准确，易操作。用海水浸泡自制的控释海水植物肥样品(编号：MRF-0201．中速型)，运用建立的氮、磷测定方法测定浸取液中的氮、磷含量，实验证明该方法可以用于研究控释海水植物肥在海水中的氮、磷的化学动力学行为。

DETERMINATION OF PHOSPHORUS AND NITROGEN IN RELEASE-CONTROLLED FERTILIZER FOR SEAWATER PLANTS

A method is established to determine nitrogen and phosphorus in a release-controlled fertilizer prepared by the authors. The sample digested by sulphuric acid can be used to determine both N and P. The complex compound of ammonium molybdate, antimony-potassium tartrate and ascorbic acid makes phosphorus available to the analy-sis method of ultraviolet visible spectrophotomatry. Nitrogen analysis is based on distil-lation of ammonium under the alkaline situation and followed titrimetry with standard sulphuric acid solution. A little dose of samples and reagents is enough for analyses in this experiment. The method is proved to be simple and operable, and can help observe the chemical dynamic behavior of nitrogen and phosphorus of release-controlled fertilizer in seawater.