Guangdong Academy of science

Guangzhou, China

Guangdong Academy of science

Guangzhou, China
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Zhu H.,South China University of Technology | Zhu H.,Guangdong Academy of science | Dai Z.,Guangdong Academy of science | Tu W.,South China University of Technology
RSC Advances | Year: 2017

In order to overcome the defects of opacity, high gas permeability, poor heat and solvent oil resistance of methyl silicone rubber, optically transparent trifluoropropyl phenyl silicone rubber was prepared by introducing trifluoropropyl and phenyl to organic silicone molecules. Then organic polysilazane (OPSZ) was coated on the trifluoropropyl phenyl silicone rubber surface with tetramethylhexamethylenediamine as a catalyst and a dense coating with low gas permeability was achieved. This process realized low-temperature curing and siliceous transition. At the same time, optical performance, mechanical properties, oxygen permeation flux, and anti-sulfuration were measured. The results showed that the fluorine-containing phenyl silicone rubber had good optical transparency, tensile strength, elongation at break, tear strength, oil resistance and heat resistance. The OPSZ coating surface was continuous, uniform, dense and free of cracks and voids; meanwhile, the coating section was dense, uniform, seamless, without cracks. The interface between the coating and the silicone rubber exhibited good adhesion. Light transmission was over 92% between 400 and 800 nm. When the coating thickness was more than 12 μm, the oxygen permeation flux remained unchanged, lamps had good anti-sulfuration ability, and luminous flux was maintained at over 99.8%. when the mass fraction of tetramethyl hexamethylene diamine (w) was over 5%, siliceous transition was achieved under room temperature and 50% relative humidity for 24 h. © 2017 The Royal Society of Chemistry.


Wang Z.,South China University of Technology | Wu B.,Guangdong Academy of Science
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011 - Proceedings | Year: 2011

The process of steel produced consumes a lot of energy. At the same time, it wastes plenty of energy because it lets combustible gas. Through the research of steel enterprise energy management optimizes the process of steel produced in order to save the energy. Through the optical fiber to connect the data collection station and control center, to achieve information integration and centralized monitoring. This system not only supports data queried, real time trend analysis, historic trend analysis, reporting and so on. By means of least squares method forecast the energy consume of working procedure. It helps the company to arrange production. This system had been used in Guangzhou Iron and Steel Co., Ltd and get benefit from it. At the same time, it can be used in another steel company. © 2011 IEEE.


Yang Y.,Guangdong Institute of Microbiology | Yang Y.,Guangdong Academy of science | Guo J.,Guangdong Academy of science | Sun G.,Guangdong Institute of Microbiology | And 5 more authors.
Bioresource Technology | Year: 2013

Microbial electrochemical snorkel (MES) reactor is a simplified bioreactor based on microbial fuel cells (MFCs) and has been suggested to be a promising approach to solve many environmental problems. However, the microbial processes in MES reactors have not yet been characterized. This study shows that Shewanella decolorationis S12 can use the conductive snorkel as direct electron acceptor for respiration and growth. Similar with current-generating biofilms, cellular viability in MES biofilms decreased with the distance from snorkel. MES reactors showed more rapid cell growth and substrate consumption than MFCs. Although the biomass density of MES biofilm was higher than that of anode biofilms, the current-generating capacity and electrochemical activity of MES biofilm were lower, which could be attributed to the lower cytochrome c expression in MES biofilm caused by the higher redox potential of MES. These microbiological and electrochemical properties are essential for the further development of MES reactors. © 2012 Elsevier Ltd.


Zhang W.,CAS South China Botanical Garden | Zhang W.,University of Chinese Academy of Sciences | Hendrix P.F.,University of Georgia | Snyder B.A.,University of Georgia | And 6 more authors.
Ecology | Year: 2010

On a local scale, invasiveness of introduced species and invasibility of habitats together determine invasion success. A key issue in invasion ecology has been how to quantify the contribution of species invasiveness and habitat invasibility separately. Conventional approaches, such as comparing the differences in traits and/or impacts of species between native and/or invaded ranges, do not determine the extent to which the performance of invaders is due to either the effects of species traits or habitat characteristics. Here we explore the interaction between two of the most widespread earthworm invaders in the world (Asian Amynthas agrestis and European Lumbricus rubellus) and study the effects of species invasiveness and habitat invasibility separately through an alternative approach of "third habitat" in Tennessee, USA. We propose that feeding behaviors of earthworms will be critical to invasion success because trophic ecology of invasive animals plays a key role in the invasion process. We found that (1) the biomass and isotopic abundances (δ13C and δ15N) of A. agrestis were not impacted by either direct effects of L. rubellus competition or indirect effects of L. rubellus-preconditioned habitat; (2) A. agrestis disrupted the relationship between L. rubellus and soil microorganisms and consequently hindered litter consumption by L. rubellus; and (3) compared to L. rubellus, A. agrestis shifted its diet more readily to consume more litter, more soil gram-positive (G+) bacteria (which may be important for litter digestion), and more nonmicrobial soil fauna when soil microorganisms were depleted. In conclusion, A. agrestis showed strong invasiveness through its dietary flexibility through diet shifting and superior feeding behavior and its indirectly negative effect of habitat invasibility on L. rubellus via changes in the soil microorganism community. In such context, our results expand on the resource fluctuation hypothesis and support the superior competitor hypothesis. This work presents additional approaches in invasion ecology, provides some new dimensions for further research, and contributes to a greater understanding of the importance of interactions between multiple invading species. © 2010 by the Ecological Society of America.


Li Y.,CAS Institute of Microbiology | Li Y.,Soochow University of China | Bao L.,CAS Institute of Microbiology | Song B.,Guangdong Academy of science | And 4 more authors.
Food Chemistry | Year: 2013

The fruiting bodies or mycelia of mushrooms have been used as food and food-flavoring material for centuries due to their nutritional and medicinal value and the diversity of their bioactive components. The present research is the first to investigate the bioactive secondary metabolites from the solid culture of the edible mushroom Neolentinus lepideus. Two new secondary metabolites, 5-methoxyisobenzofuran- 4,7(1H,3H)-dione (1) and 1,3-dihydroisobenzofuran-4,6-diol (2), as well as seven known compounds including one benzoquinone derivative (3) and six cinnamic acid derivatives (4-9) were obtained. Their structures were established by means of spectroscopic methods, including 1D and 2D NMR. The bioactivity on the nitric oxide production in lipopolysaccharide-induced macrophages was evaluated for all metabolites (1-9) isolated. Compound 1 showed strong NO inhibitory activity with the IC50 value of 6.2 μM. Compound 2 displayed moderate NO inhibitory activity with the IC50 value of 88.8 μM. In the DPPH scavenging assay, compound 2 displayed antioxidant activity with IC50 of 68.6 μM. The discovery of new NO production inhibitors from N. lepideus expands its usage as a functional food. © 2013 Elsevier Ltd.


Su Q.-Q.,Guangdong Academy of science | Su Q.-Q.,Central South University of forestry and Technology | Xiang Z.-F.,Central South University of forestry and Technology | Qin J.,Guangdong Academy of science | And 2 more authors.
Crop Protection | Year: 2014

To evaluate the dose effects of cabergoline on the fertility of female mice during early or late pregnancy, cabergoline was continuously administered by gastrogavage for three days within 1 day to 3 day or 15 day to 17 day of gestation. The body mass, reproductive rate, litter size at birth and weaning of females, as well as the body mass, survival rate of pups, were recorded. During early pregnancy, cabergoline treatment effectively terminated the pregnancy of mice. Cabergoline (100. μg/kg) was half effective in terminating pregnancy and significantly reduced the average litter size and survival rate of pups compared with those of the controls. Cabergoline treatment of 200 and 400. μg/kg completely terminated pregnancy of mice and induced incomplete restoration of fertility (40% and 44%, respectively) even at the second cycle of reproduction. During late pregnancy, cabergoline did not change the litter size at birth but significantly reduced the litter size at weaning and the survival rate of pups, 400. μg/kg cabergoline markedly reduced the survival rate to 77% compared with the controls. The death of pups mainly occurred during seven days after parturition. Cabergoline had no significant difference on the average body mass of surviving pups in treated groups compared with controls during lactation. In conclusion, cabergoline may inhibit or reduce the reproduction of female mice, and demonstrate different dose effects on the fertility during early or late pregnancy. Together with infertility efficacy in phase prior to mating and lactation, cabergoline is a potential fertility control agent for pest rodent control. © 2013 Elsevier Ltd.


PubMed | Guangdong Academy of Science and Shihezi University
Type: Journal Article | Journal: Organic & biomolecular chemistry | Year: 2016

Copper-based MOF-199 was used as an efficient heterogeneous catalyst to catalyze cross-coupling reactions between N-containing heterocycles and aryliodides with high yields. The catalyst can be easily separated from the reaction mixture, and can be reused at least 5 times without significantly decreasing the activity. The XRD results showed that the crystallinity and structure of MOF-199 can be maintained well during the coupling reaction.


Xu Z.,Guangdong Academy of science
Nan fang yi ke da xue xue bao = Journal of Southern Medical University | Year: 2012

To evaluate the effects of different CO(2) pneumoperitoneum conditions on renal function in rats and provide experimental evidence for improving renal graft function after transplantation. SD rats were randomized into 10 groups (n=12) and subject to CO(2) pneumoperitoneum at different pressures (0.67, 1.33 and 2.0 kPa) for 60 or 120 min. Serum urea nitrogen (BUN), creatinine (Cr) and N-acetyl-β-D-glocosaminidase (NAG) levels were detected after pneumoperitoneum. As the pressure and time of pneumoperitoneum increased, the renal function deteriorated gradually, showing significant differences between the groups (P<0.05). Increased pressure and prolonged duration of CO(2) pneumoperitoneum causes impairment of the renal function, suggesting the necessity of reducing the operative time and lowering the pressure of pneumoperitoneum when harvesting renal graft in living donors.


Zhang Y.,South China University of Technology | Zhan Y.,Guangdong Academy of science | Xie X.,South China University of Technology | Cheng T.,Guangdong Academy of science
Proceedings - 2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010 | Year: 2010

In the few years, several neural networks are proposed to image classification. Support vector machine classifier employs the structural risk minimization principles, which make support vector machine classifier have good generalization ability. In order to solve the problem of parameters selection of support vector machine, particle swarm optimization is applied to select the parameters of support vector machine. Therefore, support vector machine trained by particle swarm optimization is presented to image classification in the paper. The images in Corel image database are used to testify the classification performance of the proposed method. The testing results show that the classification accuracy of PSO-SVM is better than that of SVM,BP neural network, RBF neural network. © 2010 IEEE.


Zhang X.-P.,South China University of Technology | Liu G.-X.,South China University of Technology | Zhou S.-B.,Guangdong Academy of science
Guangxue Jingmi Gongcheng/Optics and Precision Engineering | Year: 2010

In consideration of the direct influence of Received Signal Strength Indicator(RSSI) fluctuation on the target localization accuracy in wireless sensor networks (WSN), the basic principle of target localization using Least Square Support Vector Regression(LSSVR) is discussed. Then, the characteristics of LSSVR modeling are analyzed for given and variable detection sensors, respectively. Furthermore, a method for Target Localization based on Adaptive LSSVR Modeling (TL-AML) in WSN is proposed. By considering localization accuracy and real-time performance comprehensively, LSSVR models are built for locating target at initial time, and at follow-up time it is used to decide whether new models need to be built or not according to the inclusion relation between detection nodes and sensor nodes. The performance of TL-AML is verified based on CC2430 WSN experiment platform. Results show that the Root Mean Square Error (RMSE) of target localization based on TL-AML has reduced by 34%~37% and 60%~65% as compared with those of MLE and LSE, respectively. When modeling parameters are taken in reasonable value ranges, the localization accuracy of TL-AML is improved evidently compared with MLE and LSE. Moreover, the consuming time of TL-AML is 0.2~0.4 s, If LSSVR modeling is needed. Otherwise, the consuming time is only about 0.04 s. The results indicate that TL-AML method can weaken the influence of RSSI fluctuation on the accuracy of target localization and has good real-time target localization accuracy.

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