We report one new method for direct synthesis of monodisperse, quasi-spherical AuAg alloyed nanocrystals (ANCs) with sizes of 11 to 25 nm and core–shell (CS) AuAg@AuAg NCs (CS AuAg ANCs) with sizes of 30 to 80 nm via the Fe2+-assisted citrate coreduction of auric ions and silver ions in a one-pot reaction. It is found that at fixed concentration of auric ions, the concentrations of ferrous ions and silver ions play key roles in tuning the size and the types of NCs (AuAg ANCs and CS AuAg ANCs), respectively. Moreover, AuAg ANCs and CS AuAg ANCs exhibit excellent and poor chemical stability in nonideal chemical environments, respectively. The potential application of these AuAg ANCs for SERS detection of industrial pollutants (such as benzidine and p-cresol) in artificial industrial wastewater has been successfully demonstrated.
An effective method based on Fe 2+ assisted cold plasma (CP) to pretreat pineapple peel cellulose for the preparation of cellulose nanofibrils (CNF) was proposed in this study. The mechanism underlying Fe 2+ assisted CP pretreatment based on the structural changes of cellulose was investigated. Results showed that the cellulose preabsorbed Fe 2+ , followed by 60 min of CP treatment, and then was nanofibrillated into CNF via ultrasonication. Fe 2+ assisted CP treatment exhibited strong capacity to significantly decrease the degree of polymerization of cellulose and to enhance electrostatic repulsion of fibrils. Furthermore, the roughness and breakage were observed on the surface of pretreated cellulose. The content of inter-molecular hydrogen bonds and average crystallite size (D hkl ) also decreased significantly. The current results provided useful fundamental insights into Fe 2+ assisted CP and cellulose interaction, which should be beneficial to developing new pretreatment methods for disintegrating cellulose into CNF.
危险品化学品经营许可证（带存储）