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In this study, chitosan (CS)-sodium sodium tripolyphosphate (STPP) (CS-STPP) nanoparticles were fabricated via reverse microemulsion-ionic gelation method. A series of experiments were conducted to optimize the constitution of reverse microemulsion system and the obtained CS-STPP nanoparticles were then characterized by Fourier transform infrared spectrum (FT-IR) and scanning electron microscope (SEM). The concentration of Tween-80 and Span-80 were 6% and 2% respectively when the ratio of water phase to oil phase was 1/7. A narrow size distribution and good dispersion of the obtained CS-STPP nanoparticles were obtained when the stirring speed was 400 rpm/min, with diameter being 552 ± 14 nm. The FT-IR results for the CS-STPP nanoparticles also indicated that the CS was cross-linked with the STPP. These results are very important for the CS-STPP nanoparticles when used as drug carriers.

Three kinds of functional monomers, 4-vinylpridine(4-VP), 2-(allylthio)nicotinic acid(ANA), and 2-Acetamidoacrylic acid(AAA), were used to synthetize palladium(II) ion-imprinted polymeric nanospheres (Pd(II) IIPs) via precipitation-polymerization method in order to study the effects of different functional monomers on the adsorption properties of ion-imprinted materials. The results of UV spectra in order to study the interaction between template ion PdCl4 2− and functional monomers showed that there were great differences in structure after the template reacted with three functional monomers, 4-VP and ANA caused a large structural change, while AAA basically did not change. Further results on the adsorption performance of Pd(II) IIPs on Pd(II) confirmed 4-VP was the most promising candidate for the synthesis of Pd(II) IIPs with an adsorption capacity of 5.042 mg/g as compared with ANA and AAA. The influence of operating parameters on Pd(II) IIP’s performance on Pd(II) adsorption was investigated. There was an increase in the adsorption capacity of Pd(II) IIPs at higher pH, temperature, and initial concentration of Pd(II). The results of multi-metal competitive adsorption experiments showed that Pd(II) IIPs had selectivity for Pd(II). An adsorption equilibrium could be reached at 180 min. Kinetic analysis showed that the adsorption test data fitted best to the pseudo-second order kinetic model, and the theoretical equilibrium adsorption capacity was about 5.085 mg/g. The adsorption isotherms of Pd(II) by Pd(II) IIPs agreed well with the Freundlich equation, suggesting a favorable adsorption reaction under optimal conditions. These results showed that Pd(II) IIPs have potential application in the removal of Pd(II) from aqueous solutions and may provide some information for the selection of functional monomers in the preparation of Pd(II) IIPs.

By investigating students' satisfaction of the Software Engineering Sino-Finnish Cooperation Program at the School of International Education, NJIT, this paper studies and analyzes the differences and existing problems between the online teaching by both Chinese and Finnish teachers. It finds that there are obvious differences between Chinese and Finnish teachers in online teaching. Chinese teachers' online teaching is teacher-centered, while Finnish teachers' online teaching is more student-oriented. Based on the questionnaire survey and references, the influence model of student satisfaction is built, and feasible suggestions are put forward, which can be a good reference for the other Sino-foreign Cooperation Programs in China.