Time filter

Source Type

Li T.,Sun Yat Sen University | Zhang Y.,Guangdong Light Industry Technical College | Song Z.,Guangdong Pharmaceutical University | Wu H.,Guangdong Pharmaceutical University | Li S.,Sun Yat Sen University
Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica | Year: 2013

To obtain antibacterial chitosan with improved dynamic mechanic properties, the Ag-MMT was dispersed in chitosan solution dissolving in acetic acid to obtain nano Ag-MMT/CS composite via solution intercalation. The Ag+ ion can be released steady and slowly from Ag-MMT/CS in vitro release test in simulated fluid. The bacterial inhibition zone diameter of Ag-MMT/CS is 9.2 mm, which is 50.6% larger than that of CS, the result shows Ag-MMT/CS's good antibacterial activity against Staphylococcus aureus. And the inhibition ratio test result suggests the significant surface area and adsorption capacities of MMT help a lot to immobilize more bacteria on the surface and improve the antibacterial activity of Ag-MMT/CS. In the dynamic thermomechanical analysis (DMA) test, the storage modulus of Ag-MMT/CS is 3261 MPa, which exhibits remarkable increase (195% larger than CS) in mechanic property.


Tian L.,Guangdong Pharmaceutical University | Yuanyuan Z.,Guangdong Light Industry Technical College | Yingying M.,Guangdong Pharmaceutical University | Ran H.,Guangdong Pharmaceutical University
Applied Clay Science | Year: 2015

The polycarbonate (PC) solution was mixed with silver loaded modified montmorillonite (Ag-Mt) and then treated with 1,4-dimethylbenzene to obtain functional Ag-Mt/PC with superhydrophobicity. The Ag-Mt/PC with the Ag-Mt content of 1.5. wt.% showed a high water CA (152.5°) and excellent durability, the water CA decreased only 10% during a week's continuously water flow at the rate of 0.2. mL/s. The scanning electron microscopy (SEM) and surface area measurement results proved that the crystallization situation was more complicated on the interface of PC and Ag-Mt interlayer, resulted in different phase separation rate, provided more opportunity for the formation of pores with appropriate size diffusion, and finally fabricated a micro-nano-scaled surface with superhydrophobicity. Otherwise the Ag-Mt/PC performed high catalytic activity on the degradation reaction of methylene blue (the nearly complete degradation took only 25. min), slow release property and antibacterial activity on both Staphylococcus aureus ATCC6535 and Escherichia coli ATCC8739 (the mean diameter of inhibition zone was almost 50% larger than PC), which indicated that this simple and inexpensive approach could be more broadly applied to fabricate large-area functionalized surface via engineering materials with superhydrophobicity and utilize potential practical applications in the future. © 2015 Elsevier B.V..


Li T.,Guangdong Pharmaceutical University | Zhang Y.,Guangdong Light Industry Technical College | Song Z.,Guangdong Pharmaceutical University | Wu H.,Guangdong Pharmaceutical University
Polymer Composites | Year: 2014

Chitosan/Ag-montmorillonite (CS/Ag-MMT) nanocomposite was obtained via solution intercalation. The X-ray diffraction and transmission electron microscopy results indicated the successful formation of intercalated-andexfoliated nanostructures at low Ag-MMT contents and intercalated-and-flocculated nanostructures at high Ag-MMT contents. The CS/Ag-MMT nanocomposite with 7 wt% Ag-MMT presented a very high inhibition ratio against Staphylococcus aureus (>70%), and its bacterial inhibition zone diameter was 3.2 mm larger than that of CS, which showed remarkable antibacterial activity. When the Ag-MMT content was 5 wt%, the E′ of CS/Ag-MMT was increased to 3,261 MPa, which was 195% higher than CS and exhibited excellent mechanic property. The DMA test results showed the Tg of CS/Ag-MMT shifted to a higher temperature, suggesting the Ag-MMT interlayer not only interacted quite strongly with the reactive groups of CS but also restricted the motion of CS macromolecules, which was also verified by Fourier transform infrared spectrum measurements. © 2014 Society of Plastics Engineers.


Li T.,Sun Yat Sen University | Zhang Y.,Guangdong Light Industry Technical College | Song Z.,Guangdong Pharmaceutical University | Wu H.,Guangdong Pharmaceutical University | Li S.,Sun Yat Sen University
Science and Engineering of Composite Materials | Year: 2013

Silver loaded montmorillonite (Ag-MMT) was prepared by ion exchange reaction under microwave irradiation. The effects of microwave irradiation time, AgNO3 concentration, and microwave power on the silver content of Ag-MMT were investigated using the Volhard method. The time of ion exchange reaction was found to be greatly shortened under microwave irradiation. The most suitable reaction condition was in 0.2 m AgNO 3 under 100% microwave power irradiation for 4 min, and the silver content was determined and was found to be 1.23 wt% . The results of the Fourier transform infrared spectrum (FT-IR) and Ag+ release tests confirmed the successful loading of silver and its good slow-release property. The X-ray diffraction (XRD) patterns and ultraviolet- visible (UV-vis) spectra proved the existence of metallic Ag nanoparticles. The Ag-MMT showing a large inhibition zone, high inhibition ratio, and low minimum inhibitory concentration (MIC) value against Staphylococcus aureus ATCC6535 presented a very good antibacterial property.


Chunjiang J.,South China University of Technology | Chunjiang J.,GuangDong Light Industry Technical College | Guangxue C.,South China University of Technology | Xiaozhou L.,South China University of Technology | And 2 more authors.
Applied Mechanics and Materials | Year: 2013

Ink jet printing, as the key point of digital printing development, has already got some progress as technical be concerned, and also it has been used in industrial producing. But until now, ink jet printing still has some problems to be solved, include satellite droplet, droplet dimension, and spreading of droplet on substrate and so on. These problems involving parameters include dimension and geometry of the print-head, quality and characteristics of the control signal, surface tension of the ink, viscosity of the ink, characteristics of the substrate surface and so on. In this paper we just analysis the influence of ink surface tension to the process from jet to formation of the droplet by establishing mathematical model, but keep other parameters unchanged. At last, we get the relationship between ink surface tension and droplet parameters, so that it can be used as theoretical basement for print-head design and researching of ink. © (2013) Trans Tech Publications, Switzerland.


Xu T.,Key Laboratory of Enhanced Heat Transfer and Energy Conservation | Xu T.,South China University of Technology | Xu T.,Guangzhou Maritime Institute | Gao X.-N.,Key Laboratory of Enhanced Heat Transfer and Energy Conservation | And 6 more authors.
Industrial and Engineering Chemistry Research | Year: 2013

Laminar flow diffusion combustion appears when liquid ethanol passes through the ceramic tubes with inner diameter of 1.0 mm, 0.6 mm and 0.4 mm and outer diameter of 2.0 mm. Due to the limitation of measurement tools, it is very difficult to measure the microflame characteristic parameters and the numerical simulation method for microflame is always employed. By comparing the simulation results and measured values, liquid droplet radiation heat transfer and boundary slip have significant effect on numerical simulation and the numerical simulation values agree well with the experimental data, which proves that the numerical simulation method is reliable. The numerical simulation results show that the flame height and width increase almost linearly with the volume flow while the maximal temperature of flame increases first and then decreases. Because the microscale effect can improve the combustion efficiency, A flame with smaller height and width and lower maximal temperature is observed at a lager inner tube diameter. © 2013 American Chemical Society.


Zeng Y.,Guangdong Light Industry Technical College | Deng M.,Guangdong Light Industry Technical College | Lv Z.,Huizhou University | Peng Y.,Huizhou University | Peng Y.,South China Normal University
SpringerPlus | Year: 2014

Extracts of 19 selected edible flowers were investigated for their free radical scavenging activity (FRSA), polyphenolic contents and flavonoid contents in the paper. The results showed the extracts of Paeonia suffruticosa Andr., Paeonia lactiflora Pall., and Rosa rugosa Thunb. possessed obviously stronger DPPH FRSA (94.221 ± 0.102; 93.739 ± 0.424 and 94.244 ± 0.163%, respectively), superoxide FRSA (55.818 ± 1.518; 52.142 ± 1.374 and 57.321 ± 0.608%, respectively), hydroxyl FRSA (85.872 ± 0.873; 89.307 ± 0.803 and 88.560 ± 0.277%, respectively) and polyphenolic contents (96.208 ± 0.689; 87.938 ± 1.187 and 92.164 ± 0.799 mg CE/g, respectively) that were superior or comparable to black and green teas. Polyphenolic contents did correlate well with DPPH FRSA (r = 0.943, P < 0.01), superoxide FRSA (r = 0.833, P < 0.01), and hydroxyl FRSA (r = 0.500, P < 0.05). It indicated that this potent FRSA may be attributed to its phenolic compounds. These findings showed that the tested flowers could be considered as new sources of safe natural antioxidants and preservatives of food industry. © 2014 Zeng et al.; licensee Springer.


Lv Z.-C.,South China Normal University | Chen K.,South China Normal University | Zeng Y.-W.,Guangdong Light Industry Technical College | Peng Y.-H.,South China Normal University | Peng Y.-H.,Huizhou University
Food Chemistry | Year: 2011

The kernels of Canarium pimela L., obtained from Guangdong Province, PR China, were analysed for their proximate composition, fatty acid composition, amino acid profile and mineral contents. The kernels were abundant in fats (59.7%) and proteins (23.9%). The acid, iodine, and saponification values of the kernel oil were 0.33, 92.4 and 191, respectively. Oleic acid (43.0%) and linoleic acid (26.5%) constituted the main unsaturated fatty acids of the kernel oil, while palmitic acid (24.8%) was the major saturated fatty acid. The kernel proteins were rich in glutamic acid, arginine and aspartic acid (21.0%, 12.5%, and 6.80%, respectively), but not the limiting amino acid lysine (2.37%). The mineral elements were also involved in this study. The results indicated that C. pimela L. kernels may be a potential source of oil or protein for the human diet. © 2010 Elsevier Ltd.


Zeng Y.-W.,South China Normal University | Zeng Y.-W.,Guangdong Light Industry Technical College | Liu X.-Z.,South China Normal University | Lv Z.-C.,South China Normal University | And 2 more authors.
Experimental and Toxicologic Pathology | Year: 2012

Ficus hirta Vahl. (Wuzhimaotao) is widely used as a folk medicine by Hakka people in southern China. In order to ascertain if any major fraction can be attributed to have pronounced anticancer effect, extracts of Wuzhimaotao on cytotoxic and apoptosis of HeLa cell lines were evaluated. HeLa cells were cultured and incubated with different concentrations of crude aqueous extracts (CAE), ethyl acetate extracts (EAE), and butyl alcohol extracts (BAE). It showed CAE, EAE, and BAE decreased cell viability on HeLa cells as a dose-dependent manner, and induced a sub-G1 peak in flow cytometry histogram of treated cells compared to the control. Apoptotic cell death is involved in CAE, EAE, and BAE toxicity, with EAE having a significant decrease in G1 population. An over all analysis of results showed that Wuzhimaotao extracts exert antiproliferative action and growth inhibition on HeLa cells through apoptosis induction which indicates its anticancer properties and deserves further investigation. © 2011 Elsevier GmbH.


PubMed | South China Normal University, Huizhou University and Guangdong Light Industry Technical College
Type: | Journal: SpringerPlus | Year: 2014

Extracts of 19 selected edible flowers were investigated for their free radical scavenging activity (FRSA), polyphenolic contents and flavonoid contents in the paper. The results showed the extracts of Paeonia suffruticosa Andr., Paeonia lactiflora Pall., and Rosa rugosa Thunb. possessed obviously stronger DPPH FRSA (94.2210.102; 93.7390.424 and 94.2440.163%, respectively), superoxide FRSA (55.8181.518; 52.1421.374 and 57.3210.608%, respectively), hydroxyl FRSA (85.8720.873; 89.3070.803 and 88.5600.277%, respectively) and polyphenolic contents (96.2080.689; 87.9381.187 and 92.1640.799mg CE/g, respectively) that were superior or comparable to black and green teas. Polyphenolic contents did correlate well with DPPH FRSA (r=0.943, P<0.01), superoxide FRSA (r=0.833, P<0.01), and hydroxyl FRSA (r=0.500, P<0.05). It indicated that this potent FRSA may be attributed to its phenolic compounds. These findings showed that the tested flowers could be considered as new sources of safe natural antioxidants and preservatives of food industry.

Loading Guangdong Light Industry Technical College collaborators
Loading Guangdong Light Industry Technical College collaborators