Fei Rong

Tailoring colloidal photonic crystals with wide viewing angles.

Photonic crystal materials are developed from colloidal crystal fibers or beads. As the fibers have cylindrical symmetry, the fiber-composed PhCs show anisotropic angle independence. By contrast, the bead-composed PhCs display angle-independent structural colors because of the spherical symmetry of their bead elements.

Photonic Crystal Beads from Gravity-Driven Microfluidics

This Letter reports a simple method for the mass production of 3D colloidal photonic crystal beads (PCBs) by using a gravity-driven microfluidic device and online droplet drying method. Compared to traditional methods, the droplet templates of the PCBs are generated by using the ultrastable gravity as the driving force for the microfluidics, thus the PCBs are formed with minimal polydispersity. Moreover, drying of the droplet templates is integrated into the production process, and the nanoparticles in the droplets self-assemble online. Overall, this process results in PCBs with good morphology, low polydispersity, brilliant structural colors, and narrow stop bands. PCBs could be bulk generated by this process for many practical applications, such as multiplex-encoded assays and the construction of novel optical materials.

Ultrasound Frequency Impacts on the Removal of Indigenous Blue-Green Algae Taken from Lake Taihu

This paper studied the ultrasonic removal of indigenous blue-green algae taken from Lake Taihu. The results showed that higher ultrasound frequency benefited the removal of indigenous algae. But in consideration of complex condition of the natural lakes and reservoirs such as the lack of powerful electrical supply system, low sound frequency is more suitable. Because of slightly improvement in the algae removal rate constants among the low frequency range (20-100 kHz), 20 kHz is the best ultrasound frequency for indigenous algae removal. Moreover, little change in the microcystins concentration was found with sonication at 20 kHz, 2W for 60s, which was compared with the increased microcystins from 2.67 to 2.851 mg/L after sonication at 1000 kHz, 2W for 60s. the concentration of chlorophyll.

Study on the Effect of Functional Monomer on the Binding Characteristics of Molecularly Imprinted Polymer

Three kinds of molecularly imprinted polymers (MIPs) were prepared with S-naproxen as template molecule, and methacrylic acid, acrylamide, 4-vinyl pyridine as functional monomers, respectively. The interaction between template molecule and different monomers were analyzed by UV spectra. Binding experiments and Scatchard analysis were adopted to compare the binding characteristics of MIPs. The results showed that the MIP based on 4-vinyl pyridine possessed the highest adsorption amount of 1.73 μmol for the template molecule, while the MIP based on methacrylic acid presented the lowest binding characteristic, which correlated positively with the interaction strength concluded by UV analysis.

Study on the Weakest Interaction Model for Chiral Resolution Using Molecularly Imprinted Polymer

Molecularly imprinted polymers (MIPs) of L-phenylalanine ethyl ester were synthesized in this study. Then, the prepared MIPs were packed in a stainless column and evaluated as the chiral stationary phases of high performance liquid chromatography (HPLC). The MIPs exhibited a considerable capability of chiral separation between template molecule and its enantiomer with the separation factor of 1.69. Furthermore, the weakest interaction model was introduced to study the chiral recognition mechanism of MIPs. The results suggested that the weakest interaction between the template molecule and the imprinted cavity played crucial role in chiral separation, and the molecular tension should be taken into consideration during the separation procedure. The separation factor of 2.07 was calculated by the theoretical model, which was very close to the value obtained from chromatographic experiment.

Study on the Treatment of PTA Productive Wastewater Using Ultrasound Enhanced Ozonation

This paper reports a scale treatment on purified terephthalic acid (PTA) productive wastewater in a 50L column form reactor by ultrasound enhanced ozonation. The degradation effects of three kinds of productive wastewater including inlet and outlet water from treatment works as well as accident wastewater are investigated. The results show that the ultrasound enhanced ozonation is an efficient way for the treatment of PTA productive wastewater, compared with traditional physicochemical and biological process. The chemical oxygen demand (COD) values of PTA productive wastewaters drop to less than 100 mg/L after treatment, meeting the requirements of industrial effluent quality standard of China, and the maximum removal rate can reach as high as 99.1%.

Study on Photocatalytic Degradation of X-3B by TiO2 Nanotube Arrays

In the present work, highly ordered TiO2 nanotube array with diameter were fabricated by one-step or two-step anodization of titanium foils. The prepared arrays were characterized by field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activity of the TiO2 nanotube arrays was determined by degradation of X-3B under UV and compared to direct photolysis. The results showed that its photocatalytic activity in degradation of X-3B had been dramatically enhanced as compared to direct photolysis, and the photocatalytic performance of TiO2 nanotube arrays prepared by one-step anodization was better than that made by two-step anodization. Furthermore, adsorption performance analysis suggested that the higher catalytic activity of one-step nanotube array was attributed to its larger apparent maximum number.

Study on the Degradation of Low Molecular Organics Using Boron-Doped Diamond Electrode

Boron-doped diamond (BDD) electro- catalysis is one of the advanced oxidation processes (AOPs) can be widely applied in water treatment, because the unique physical and chemical properties enable BDD to be an ideal anode material in electrochemical oxidation of aqueous organic pollutants. In this work, electrocatalysis is conducted in research of treating isopropyl alcohol model wastewater and real wastewater of low molecular organics on BDD electrode. Experiments are performed both in static and dynamic mode with a batch reactor and a circulation cell, and the effect of current density is investigated. The results reveal the superiority of dynamic mode in treating model wastewater and real wastewater. And the optimum working currency density of dynamic electrocatalysis for model wastewater and real wastewater are 1.29mA/cm2 and 3.84mA/cm2, respectively.