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Wu G.,South China Normal University | Zhai W.,South China Normal University | Sun F.,South China Normal University | Sun F.,Guangdong Higher Education Institutes | And 3 more authors.
Materials Research Bulletin | Year: 2012

Morphology-controlled Cu 2O microcrystalline particle films had been successfully electrodeposited on tin-doped indium oxide glass substrates in CuSO 4 solutions containing different amounts of polyethylene glycol (PEG) additives. With an increase of PEG, microcrystals gradually changed from irregular shapes to cubes, octahedrons, and spherical shapes. Sizes increasingly became smaller with an increase of PEG under the same deposition time. These films had been first used as recyclable photocatalysts and showed excellent and photocatalytic activities in photodegradation of methylene blue (MB) under sunlight. Activities were regularly varied relative to the morphologies of films controlled by the amount of PEG and could be further enhanced by adding a little amount of hydrogen peroxide in the MB solution. The method for controllable preparation of Cu 2O microcrystals with photocatalytic activities was simple and inexpensive. The as-prepared particle films could also be used in photodegradation of many other pollutants under sunlight. © 2012 Elsevier Ltd. All rights reserved.


He Y.,Sun Yat Sen University | He Y.,Guangdong Higher Education Institutes | Lin K.,Sun Yat Sen University | Lin K.,Guangdong Higher Education Institutes | And 2 more authors.
Mathematical Problems in Engineering | Year: 2013

Variability and availability of water resources under changing environment in a regional scale have been hot topics in recent years, due to the vulnerability of water resources associated with social and economic development. In this paper, four subbasins in the Dongjiang basin with a significant land use change were selected as case study. Runoffs of the four subbasins were simulated using the SCS monthly model to identify the quantitative impacts of land use and climate change. The results showed that (1), in the Dongjiang basin, temperature increased significantly, evaporation and sunlight decreased strongly, while precipitation showed a nonsignificant increase; (2) since the 1980s, land uses in the Dongjiang basin have experienced a significant change with a prominent increase in urban areas, a moderate increase in farmlands, and a great decrease in forest areas; (3) the SCS monthly model performed well in the four subbasins giving that the more significant land use change in each subbasin, the more runoff change correspondingly; (4) overall, runoff change was contributed half and half by climate change and human activities, respectively, in all the subbasins, in which about 20%30% change was contributed by land use change. © 2013 Yanhu He et al.


Yu J.,University of Sichuan | Yu J.,Guangdong Higher Education Institutes | Ho W.-T.,Commission on Environmental Consultation | Lu H.-M.,Guangdong Higher Education Institutes | Yang Y.-F.,Guangdong Higher Education Institutes
Environmental Monitoring and Assessment | Year: 2011

In order to understand the water quality and the genotoxicity of various surfaces in the Guangzhou section of the Pearl River during January to December of 2008, we investigated and studied the current water situation of the surface microlayer (SML) and the subsurface water (SSW) in Guanzhou section (Zhongda Dock and Yuzhu Dock) of the Pearl River by chemical analysis and biological monitoring method (Vicia faba micronucleus test). The results showed that during these months concentrations of the indexes of the two docks water such as total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD) exceeded the national III level of surface water quality, and the indexes of SML were much higher than the ones of SSW (P< 0.05), and the exceeding rate of TN, TP of SML was 100%. According to the eutrophic evaluation standard, the water bodies of SML and SSW in the two docks were in a eutrophication during these months. The eutrophication and pollution of SML was more serious, and the highest index of eutrophication (E value) was up to 81.9, which also had obvious difference with COD and TP (P< 0.05). The water of SML in the two docks enriched to N, P, and chlorophyll a (Chl. a) seriously, and the enrichment factor of SML in Zhongda Dock to N, P, and Chl. a was 0.71 ∼ 2.78, 0.98 ∼ 1.18, and 0.49 ∼ 13.99, respectively, and the one in the Yuzhu Dock was 1.09 ∼ 1.52, 1 ∼ 1.14, and 0.72 ∼ 4.07, respectively. Through inspecting the water genotoxicity of various layers by V. faba micronucleus test, we could know that the average annual MCN‰ of SML and SSW in the two docks was 6.09‰, 5.53‰, 5.57‰, and 5.249‰, respectively. In general, the above value of SML was a little higher than the one of SSW, but there was not a remarkable difference (P> 0.05). This research shows that the water quality in a medium to heavy eutrophication in the Guangzhou section of Pearl River belongs to national III ∼ IV level, and SML has the capability of enrichment to the pollutants such as N and P and induces the increase of micronucleus rate of V. faba tip cell. The study also indicates that there may be genotoxicity matters such as N, P in water body. © 2010 Springer Science+Business Media B.V.


Wang Q.,Jinan University | Wang Q.,Guangdong Higher Education Institutes | Feng X.,Chinese Academy of science | Yang Y.,Jinan University | And 2 more authors.
Environmental Toxicology and Chemistry | Year: 2011

Total mercury (THg) and methylmercury (MeHg) concentrations in four size fractions of plankton from three sampling stations in the Hg-contaminated and eutrophic Baihua Reservoir, Guizhou, China, were investigated for biomagnification and trophic transfer of Hg at different sites with various proximity to the major point sources of nutrients and metals. Total Hg concentrations in plankton of the various size fractions varied from 49 to 5,504ngg -1 and MeHg concentrations ranged from 3 to 101ngg -1. The percentage of Hg as MeHg varied from 0.16 to 70%. Total Hg and MeHg concentrations in plankton samples differed among the three sampling stations with different proximities from the major point sources. The plankton from the site closest to the dam contained the highest concentrations of MeHg. The successive increase of the ratios of MeHg to Hg from seston to macroplankton at all sites indicated that biomagnification is occurring along the plankton food web. However, biomagnification factors (BMF) for MeHg were low (1.5-2.0) between trophic levels. Concentrations of THg in seston decreased with an increase of chlorophyll concentrations, suggesting a significant dilution effect by the algae bloom for Hg. Eutrophication dilution may be a reason for lower MeHg accumulation by the four size classes of plankton in this Hg-contaminated reservoir. © 2011 SETAC.


Li G.,Shantou University | Li G.,Hong Kong University of Science and Technology | Xu X.,Shantou University | Xu X.,Guangdong Higher Education Institutes | And 5 more authors.
Journal of Cleaner Production | Year: 2015

The large amounts of abandoned oyster-shells in ostrea-culture have led to serious environmental problems and health hazards. This paper presents a parametric experimental study on the recycling of calcined oyster-shells ash (OS) to replace lime in the production of unfired fly ash bricks (UFB). Experiments were conducted with five different replacement levels of OS (between 0% and 20%) to study the effect on mechanical strength and freeze-thaw resistance. In addition, this study investigates the effect of wet-dry cycles on the shrinkage, water absorption and strength of UFB samples. According to the test results, the bricks incorporating OS and lime achieved 28-day strength and durability within grade M15 according to GB/T2542-2012 (Chinese Standard). Moreover, the wet-dry cycles within the investigated limits in this study showed positive effect on mechanical properties, indicating that the bricks are usable in both wet and dry environmental conditions. The present investigation demonstrates a potential application of waste OS that can enhance the sustainable of society by reducing environmental pollution by converting hazardous waste into useful construction material. © 2014 Elsevier Ltd. All rights reserved.


Gu Y.-G.,Jinan University | Wang Z.-H.,Jinan University | Wang Z.-H.,Guangdong Higher Education Institutes | Lu S.-H.,Jinan University | And 5 more authors.
Environmental Pollution | Year: 2012

Growing concerns surround the mid Guangdong coasts, one of China's fastest and developing economical regions. To study the environmental impacts of economic and industrial development, we measured ten metallic elements (Hg, Pb, Cu, Zn, Fe, Al, Ni, Sr, Li, and Co) in surface sediments from nineteen stations in three bays. All these metals showed concentrations substantially higher than their background values, suggesting possible anthropogenic pollution. Highest metal levels were close to the nuclear power plants likely as a result of nuclear waste discharges. Results revealed that Hg, Pb, and Sr largely originated from human activities, while Cu, Ni, Co, Al, and Fe mainly from natural rock weathering. Two types of anthropogenic sources were identified through a principal component analysis, one from shipping industry, port transport service and nuclear power plants, and the other from municipal sewage and coal power plant. © 2011 Elsevier Ltd. All rights reserved.


Liao Y.H.,Guangdong Higher Education Institutes | Rao M.M.,Guangdong Higher Education Institutes | Li W.S.,Guangdong Higher Education Institutes | Yang L.T.,Guangdong Higher Education Institutes | And 3 more authors.
Journal of Membrane Science | Year: 2010

A new gel polymer electrolyte (GPE), fumed silica-doped poly(butyl methacrylate-styrene) (P(BMA-St))-based gel polymer electrolyte, was developed for lithium ion battery. The copolymer P(BMA-St) was synthesized by emulsion polymerization, the copolymer membranes doped with and without fumed silica were prepared through phase inversion, and the GPEs were obtained by immersing the membranes in 1 M LiPF6 solution. The structure and performances of the copolymer, the membranes and the GPEs were characterized by Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), scanning electron spectroscopy (SEM), thermogravimetric analysis (TGA), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The copolymer P(BMA-St) is formed through the breaking of the double bond C{double bond, long}C in the monomers, butyl methacrylate and styrene. By doping 10 wt.% fumed silica in P(BMA-St) membrane, the properties of the membrane and the corresponding GPE were improved. The membrane doped with fumed silica is stable up to 355 °C and its pore size becomes more uniform and smaller; oxidative decomposition potential of the GPE doped with fumed silica is raised to 5.2 V (vs. Li/Li+) and its ionic conductivity is as high as 2.15 × 10-3 S cm-1 at ambient temperature. © 2010 Elsevier B.V. All rights reserved.


Zeng S.,Guangdong Ocean University | Zeng S.,Guangdong Higher Education Institutes | Yin J.,Guangdong Ocean University | Yin J.,Guangdong Higher Education Institutes | And 7 more authors.
Food Chemistry | Year: 2012

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were extracted from the skin of cobia (Rachycentron canadum). The yields of ASC and PSC were 35.5% and 12.3%, respectively. Based on the protein patterns and carboxymethyl-cellulose chromatography, ASC and PSC were composed of α1α2α3 heterotrimers and were characterised as type I collagen with no disulfide bond. Their amounts of imino acids were 203 and 191 residues per 1000 residues, respectively. LC-MS/MS analysis demonstrated the high sequences similarities of ASC and PSC. Fourier transform infrared spectroscopy spectra showed that the amide I, II and III peaks of PSC were obtained at a lower wave number compared with ASC. The thermal denaturation temperatures of ASC and PSC, as measured by viscometry, were 34.62 and 33.97 °C, respectively. The transition temperatures (Tmax) were 38.17 and 36.03 °C, respectively, as determined by differential scanning calorimetry (DSC). Both collagens were soluble at acidic pH and below 2% (w/v) NaCl concentration. © 2012 Elsevier Ltd. All rights reserved.


Zhu S.Q.,Jinan University | Zhu S.Q.,Guangdong Higher Education Institutes | Wang S.E.,Jinan University | Chen Z.Q.,Jinan University | And 3 more authors.
Laser Physics | Year: 2012

This paper reported a passively Q-switched 532 nm green laser of LD pumped V cavity structure by using Nd:YAG/Cr 4+:YAG composite crystal and the type II phase matching KTP crystal. Under 19.4 W pump power, the average power of the laser pulse up to 1.83 W, with the pulse width of 93.2 ns and repetition frequency of 9.1 kHz. © Pleiades Publishing, Ltd., 2012.


Wang Y.,Sun Yat Sen University | Lin Z.,Sun Yat Sen University | Sun L.,Sun Yat Sen University | Sun L.,Guangdong Higher Education Institutes | And 9 more authors.
British Journal of Cancer | Year: 2014

Background:Epithelial-mesenchymal transition (EMT) is a crucial programme in cancer metastasis. Epidermal growth factor (EGF) is a key inducer of EMT, and Ezrin has an important role in this process. However, how Ezrin is activated and whether it mediates EGF-induced EMT in tongue squamous cell carcinomas (TSCCs) through activating NF-κB remains obscure.Methods:We used two TSCC cell lines as a cell model to study invasion and EMT in vitro, and used nude mice xenografts model to evaluate metastasis of TSCC cells. Finally, we evaluated the level of pEzrin Tyr353, nuclear p65 and EMT markers in TSCC clinical samples.Results:Ezrin Tyr353 was phosphorylated through Akt (but not ERK1/2, ROCK1) pathway, and lead to the activation of NF-κB in EGF-treated TSCC cells. Akt and NF-κB inhibitors blocked EGF-induced EMT, and suppressed invasion and migration of TSCC cells. In vivo, silencing Ezrin significantly suppressed EGF-enhanced metastasis of TSCC xenografts. Finally, high levels of expression of pEzrin Tyr353, nuclear p65, vimentin and low level of expression of E-cadherin were correlated with cancer metastasis and poor patient prognosis.Conclusion:Our data suggest that Akt/Ezrin Tyr353/NF-κB pathway regulates EGF-induced EMT and metastasis inTSCC, and Ezrin may serve as a therapeutic target to reverse EMT in tongue cancers and prevent TSCC progression. © 2014 Cancer Research UK.

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