Time filter

Source Type

Foshan, China

Hu J.,Jinan University | Wan D.,Jinan University | Zhu W.,Jinan University | Huang L.,Jinan University | And 3 more authors.
ACS Applied Materials and Interfaces | Year: 2014

A novel cross-linked quaternized composite anion-exchange membrane based on poly(epichlorohydrin) (PECH) was prepared by a facile route. First, PECH was cross-linked with 2-methylimidazole and combined with a poly(tetrafluoroethylene) (PTFE) membrane to form cross-linked PECH/PTFE (CPECH/PTFE). Then, CPECH/PTFE was quaternized by 1-methylimidazole to obtain cross-linked quaternized PECH/PTFE (CQPECH/PTFE). 1H NMR and Fourier transform infrared spectroscopic data indicated that CQPECH was successfully synthesized, and the CQPECH/PTFE membrane had a dense and homogeneous structure demonstrated by the field-emission scanning electron microscopy. The results showed that the use of 2-methylimidazole as the cross-link agent could avoid the solubility of the composite membrane in water and dimethyl sulfoxide. With an increase of 2-methylimidazole, the solubility of the PECH ionomer was decreased. M-3, one of the CQPECH/PTFE membranes, showed good thermal properties (stable below 250 °C under an N2 atmosphere), excellent mechanical strength (a tensile strength of 67.3 MPa), moderate water uptake of 45.3%, and very low swelling degree of 9.01% at 30 °C. Besides, M-3 showed a hydroxide conductivity of up to 27 mS/cm and good long-term stability in a 1 M KOH solution at 60 °C for 15 days. In addition, a single H2/O 2 fuel-cell test using M-3 at 50 °C indicated a peak power density of 23 mW/cm2. These results suggested that the CQPECH/PTFE membrane had a good perspective for application in an alkaline fuel cell. © 2014 American Chemical Society.

Zhang L.,Jinan University | Du L.,Jinan University | Yu X.,Jinan University | Tan S.,Jinan University | And 4 more authors.
ACS Applied Materials and Interfaces | Year: 2014

Electron-hole recombination is one of the major factors limiting the efficiency of ZnO-based photocatalysts. In this work, a 2-fold enhancement strategy was employed to suppress electron-hole recombination and boost photocatalytic efficiency. First, significantly enhanced photocatalytic activity of ZnO by introducing graphene oxide (GO) was systematically investigated. Hybrid photocatalysts with different weight ratios of ZnO to GO (from 0.95:0.05 to 0.70:0.30) were synthesized and characterized. The results indicated that when the proportion ratio of ZnO to GO reached 0.85:0.15, the as-synthesized ZnO-GO nanocomposite exhibited the maximum photocatalytic efficiency on methylene blue with an apparent rate constant κapp almost 10 times faster than that of pure ZnO under UV illumination. GO was suggested to enhance the photocatalytic activity of ZnO because of its great capability in dye adsorption and charge separation. Second, Pd nanoparticles were introduced to decorate ZnO-GO to produce generally better photocatalyst ZnO-GO-Pd nanocomposites. The junction between Pd and ZnO was believed to also effectively separate the photogenerated charges due to the metal-semiconductor diode effect. These two systems of ZnO-GO and ZnO-GO-Pd nanocomposites are expected to have a broad range of applications in environmental conservation. © 2014 American Chemical Society.

Liang J.-J.,Guangdong Polytechnic
Proceedings of the 5th International Asia Conference on Industrial Engineering and Management Innovation, IEMI 2014 | Year: 2014

With the development of mobile Internet, ecommerce extensions make the payment from the Internet to the mobile Internet, it brings convenience to people, while it also brings security issues. In order to solve the trust of the mobile e-commerce payment terminals, this paper uses twoway trust authentications between the clients and the certification center to protect the trust of the payment terminals, while based on k-CAA problem in GDH group, this paper proposed an efficient authentication scheme. In the standard model, the identity authentication protocol can resist posing attack in parallel reset attack. Due to the simple interaction, low storage capacity, high efficiency and good safety performance, the identity authentication protocol is more applicable to mobile terminal equipments which havelimited computing and storage capacity. © Atlantis Press and the authors 2015.

Green building materials in the industry is also known as natural building materials, construction materials and environmental health building materials. Green building materials development and utilization are the construction of the following types, one is to save resources, and such as fly ash mixture is to reduce the consumption of natural resources. Wireless sensor network of Zigbee is used for data communication based on sensor networks. The paper proposes research of green building materials and engineering system development based on wireless sensor Zigbee technology. Experimental results show that the proposed technology has high efficiency. © (2013) Trans Tech Publications, Switzerland.

Xiao Y.,Jinan University | Zhang J.,Jinan University | Cai X.,Guangdong Polytechnic | Tan S.,Jinan University | And 7 more authors.
Optics Express | Year: 2014

Graphene-based electrical chemical vapor sensors can achieve extremely high sensitivity, whereas the comparatively slow sensing response and recovery, the research focused on only low concentration detection, have been known as drawbacks for many applications requiring rapid and high concentration detection. Here we report a novel graphenebased fiber-optic relative humidity (RH) sensor relying on fundamentally different sensing mechanism. The sensor can achieve power variation of up to 6.9 dB in high relative humidity range (70-95%), and display linear response with correlation coefficient of 98.2%, sensitivity of 0.31 dB/%RH, response speed of faster than 0.13%RH/s, and good repeatability in 75- 95%RH. Theoretical analysis of sensing mechanism can explain the experimental result, and reveal the broad applying prospect of the sensor for other kinds of chemical vapor detection. This novel graphene-based optical sensor provides a beneficial complement to the existing electrical ones, and will promote the employment of graphene in chemical sensing techniques. © 2014 Optical Society of America.

Discover hidden collaborations