To explore the effect of exogenous application of chlorinated amino acetic acid on cadmium (Cd) transport characteristics in rice seedlings, X24 and Z35 rice were taken as the research objects to carry out hydroponics experiments, and the changes of Cd content in rice seedlings, rice mineral elements and amino acid content in rice were analyzed. The results showed that exogenous application of 1.2 mmol·L−1 chlorinated amino acetic acid inhibited cadmium in shoots and roots of rice seedlings; Cd content in shoots and roots were reduced by up to 62.19% and 45.61%, respectively. The majority of cadmium was in the cell wall of shoots and roots; this decreased with the increase of the concentration of chlorinated acetic acid. In addition, the Mn content in shoots and Ca content in roots of rice seedlings increased significantly after the application of chlorinated amino acetic acid. The results of amino acid analysis showed that the contents of aspartic acid, glutamic acid and cystine in rice seedlings were increased. These results indicate that exogenous application of chlorinated amino acetic acid is beneficial to the synthesis of aspartic acid, glutamic acid and cysteine in rice seedlings, increases the content of Mn in shoots and Ca in roots of rice seedlings, and significantly alleviates cadmium stress in seedlings. This provides a theoretical basis for the development of an environmentally friendly Cd-lowering foliar fertilizer for rice.
Perovskites with nano-flexible texture structures and excellent catalytic properties have attracted considerable attention for persulfate activation in addressing the organic pollutants in water. In this study, highly crystalline nano-sized LaFeO3 was synthesized by a non-aqueous benzyl alcohol (BA) route. Under optimal conditions, an 83.9% tetracycline (TC) degradation and 54.3% mineralization were achieved at 120 min by using a coupled persulfate/photocatalytic process. Especially compared to LaFeO3-CA (synthesized by a citric acid complexation route), the pseudo-first-order reaction rate constant increased by 1.8 times. We attribute this good degradation performance to the highly specific surface area and small crystallite size of the obtained materials. In this study, we also investigated the effects of some key reaction parameters. Then, the catalyst stability and toxicity tests were also discussed. The surface sulfate radicals were identified as the major reactive species during the oxidation process. This study provided a new insight into nano-constructing a novel perovskite catalyst for the removal of tetracycline in water.