Maoming Polytechnic

Maoming, China

Maoming Polytechnic

Maoming, China
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Jiang W.X.,Dongguan Polytechnic | Hu X.Z.,Dongguan Polytechnic | Wang S.,Dongguan Polytechnic | Liang Y.,Maoming Polytechnic
Applied Mechanics and Materials | Year: 2014

According to different node data access objects, and based on the idea of behavior-driven development, an interface-oriented node data access tool is designed and implemented. The tool mainly implements an executable node data access tool that is based on MFC, and writes a set of Win32 console application, which improves the node data automation access scripts and encapsulates the module interfaces, thus improving the distributed network data access speed. © (2014) Trans Tech Publications, Switzerland.


Chen S.-F.,Maoming Polytechnic | Zhang H.,University of Rhode Island | Lin Q.-Y.,Hezhou University
Water Science and Technology | Year: 2013

This study evaluates the time-dependent dissolution of nanosilver (nAg) in common electrolytes and natural waters. nAg was synthesized via Tollens' method using sodium citrate as stabilizer; its morphology, UV-Vis spectrum, and particle size were characterized. The dissolved silver was monitored over time using filtration, centrifugation, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Our results indicated that nanoparticle aggregation, Cl- presence, and natural organic compounds could affect the dissolution behavior of nAg. The dissolution of nAg was highly dependent on Cl- concentration. Excessive Cl- enhanced nanoparticle dissolution, whereas natural organic compound inhibited the dissolution. The dissolution data fitted well with the first-order kinetic model, and the dissolution rate coefficients were calculated using the first-order equation. This study showed the dissolution of nAg under various water conditions. The obtained results may be helpful in predicting nAg behavior in relevant environmental aquatic systems. © IWA Publishing 2013.


Chen S.-F.,Maoming Polytechnic | Zhang H.,Kingston University
Water Science and Technology | Year: 2014

The present study seeks to elucidate the effect of different electrolytes on the stability of citrate-coated silver nanoparticles synthesized by the reduction of the Ag(NH3)2 + complex via Tollens' method. Time-resolved dynamic light scattering technique was used to measure the aggregation behavior of the nanoparticles over a range of electrolyte (NaCl, CaCl2, and AlCl3) concentrations. From the aggregation kinetic data, the critical coagulation concentration values were calculated as 0.11, 1.7 × 10-3, and 5.06 × 10-6 M for NaCl, CaCl2, and AlCl3, respectively. Supernatant of the nanoparticle suspension in presence of the three electrolytes was collected and measured using inductively coupled plasma mass spectrometry to quantify the sedimentation. It was found that the silver nanoparticle aggregates settled rapidly in the slow aggregation and fast aggregation regimes. Their sedimentation followed a nanoparticle size-dependent manner. © IWA Publishing 2014.


Peng Z.-Y.,Maoming Polytechnic | Zhong Y.-B.,Guangzhou University | Ge L.,Maoming Polytechnic
Advances in Intelligent Systems and Computing | Year: 2014

Time Table Problem (TTP) is a constraint Combinational Optimization Problem (COP) with multi- objective. Based on the analysis of advantages and disadvantages of Genetic Algorithm (GA) and Kruskal Algorithm (KA), this chapter put forward to a new hybrid algorithm—the Shortest path-based Genetic Algorithm (SPGA), which has the advantages of both GA and KA. In this algorithm, fitness function, selection operator, crossover operator and mutation operator are studied deeply and improved greatly, so that the hybrid algorithm can be used in the actual course arrangement. The simulation results show the effectiveness of this method. © Springer-Verlag Berlin Heidelberg 2014.


The soluble chitooligosaccharides (COS) was used to modify yeast β-d-fructofuranosidase (YFF) (EC 3.2.1.26). Effects of pH, temperature, reaction time, the ratio of COS/YFF contents, and sucrose content on the modification process were studied by orthogonal experiments. The changes in enzymatic properties, kinetic parameters, infrared spectra (IR), ultraviolet absorption spectra (UAS), ultraviolet differential spectra (UDS), and fluorescence emission spectra (FES) of enzyme after modification were investigated. The activity of the modified enzyme (COSFF) was increased by 153.5% as compared to that of YFF activity. The optimal pH for COSFF was 4.5 while that for YFF was 5.0. The optimal temperature of the enzyme was unchanged after modification. The stability of COSFF was improved to certain extent. COSFF retained 98% activity after incubation at pH 4.0, 50°C for 2h, while YFF remained only 59.8%. Residual activity of YFF and COSFF incubated at 60°C for 2h was 9% and 29%, respectively. Km of YFF was 91.11mmol/L and vmax was 1.111mmol reducing sugar/(mgmin). Km of COSFF was reduced to 47.78mmol/L but the vmax of COSFF was unchanged. After modification, IR spectra of COSFF varied obviously. The two characteristic UAS peaks were red shifted by 2nm and 3nm, respectively. © 2014 Elsevier Inc.


Ke C.,Maoming Polytechnic
Proceedings - 2013 6th International Conference on Business Intelligence and Financial Engineering, BIFE 2013 | Year: 2014

In recent years, China's retail industry growing prosperity. From macro and micro perspective, this paper systematically analyzed the Maoming area's retail marketing environment. The results showed that the retail of Maoming have a great development space, county-level cities, the rural market still has a great potential, we should vigorously develop county-level city, town and village's retail market, building business networks in rural. In addition, medicine retail needs further development, and the network marketing is the development trend in the future. Through this study, hope can provide guidance for further prosperity and development of this local retail, and promote its sustainable development. © 2013 IEEE.


Li C.,Maoming Polytechnic | Huang Z.,South China Agricultural University | Wang C.,Maoming Polytechnic
Gaodeng Xuexiao Huaxue Xuebao/Chemical Journal of Chinese Universities | Year: 2015

Chemical modification is an important pathway to transform the catalytic activity and enzymological properties of enzymes. In order to improve the catalytic activity and enzymological stability of laccase from Trametes versicolor(EC 1.10.3.2, TvL), the enzyme was purified by DEAE 52 weak anion exchange resin chromatography. The pure enzyme was activated by NaIO4. The activated enzyme was chemically modified with chitooligosaccharides(COS, average relative molecular weight 5000). The optimal modification conditions by single factor and orthogonal experiments were: temperature 5 ℃, pH=4.0, 100 mg NaIO4, 20 mg COS. Under these conditions the activity of modified enzyme(COS-TvL, 456.00 U/mg) was 145.04% of that of unmodified enzyme(TvL, 314.39 U/mg). The results of SDS-PAGE experiments indicated that the relative molecular weights of 3 polypeptides of TvL were 58100, 45200 and 21600, respectively. But the relative molecular weights of 3 polypeptides of COS-TvL were 62900, 53300 and 39700, respectively. This meant that the modification experiments were successful. The amino modification rates changed from 0 of TvL to 30.7% of COS-TvL. The optimal pH values of TvL and COS-TvL were 4.0 and 3.5-4.0, respectively. The optimal temperatures of TvL and COS-TvL were 40 and 45 ℃, respectively. The results of kinetic study indicated that Km and vmax of TvL were 9.929 mmol/L and 714.29 mmol/(mg·min). But the Km and vmax of COS-TvL were 8.989 mmol/L and 1250 mmol/(mg·min), respectively. The infrared spectra, the ultraviolet absorption spectra, the ultraviolet differential spectra, and fluorescence emission spectra of TvL and COS-TvL were also studied and analyzed. ©, 2015, Higher Education Press. All right reserved.


Feng C.,Maoming Polytechnic
BioTechnology: An Indian Journal | Year: 2014

With emergence and development of air conditioner technology, Chinese air conditioner technology has been further optimized in energy conservation and environmental protection aspects, so usage of air conditioner appears in every corner of modern buildings, some buildings even install integral central air conditioner, there are partial civil buildings install space to locate air conditioner for every users so as to keep standardized specification of whole floors. But excessive relying on air conditioner in view of energy and air, it not only causes wastes, but also leads to destroy natural environment in some aspects, so building ventilation problem should be further promoted. The paper firstly analyzes specified ventilation seasons or air conditioner seasons' building ventilation problems, and carries on fuzzy comprehensive evaluation on Chinese civil building's building ventilation problem from energy consumption aspect, improving residents' comfort level, spatial arrangement and building techniques aspect. © Trade Science Inc.


PubMed | Maoming Polytechnic
Type: | Journal: Enzyme and microbial technology | Year: 2014

The soluble chitooligosaccharides (COS) was used to modify yeast -D-fructofuranosidase (YFF) (EC 3.2.1.26). Effects of pH, temperature, reaction time, the ratio of COS/YFF contents, and sucrose content on the modification process were studied by orthogonal experiments. The changes in enzymatic properties, kinetic parameters, infrared spectra (IR), ultraviolet absorption spectra (UAS), ultraviolet differential spectra (UDS), and fluorescence emission spectra (FES) of enzyme after modification were investigated. The activity of the modified enzyme (COSFF) was increased by 153.5% as compared to that of YFF activity. The optimal pH for COSFF was 4.5 while that for YFF was 5.0. The optimal temperature of the enzyme was unchanged after modification. The stability of COSFF was improved to certain extent. COSFF retained 98% activity after incubation at pH 4.0, 50 C for 2 h, while YFF remained only 59.8%. Residual activity of YFF and COSFF incubated at 60 C for 2 h was 9% and 29%, respectively. Km of YFF was 91.11 mmol/L and vmax was 1.111 mmol reducing sugar/(mg min). Km of COSFF was reduced to 47.78 mmol/L but the vmax of COSFF was unchanged. After modification, IR spectra of COSFF varied obviously. The two characteristic UAS peaks were red shifted by 2 nm and 3 nm, respectively.


PubMed | Maoming Polytechnic
Type: Journal Article | Journal: Water science and technology : a journal of the International Association on Water Pollution Research | Year: 2013

This study evaluates the time-dependent dissolution of nanosilver (nAg) in common electrolytes and natural waters. nAg was synthesized via Tollens method using sodium citrate as stabilizer; its morphology, UV-Vis spectrum, and particle size were characterized. The dissolved silver was monitored over time using filtration, centrifugation, and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Our results indicated that nanoparticle aggregation, Cl(-) presence, and natural organic compounds could affect the dissolution behavior of nAg. The dissolution of nAg was highly dependent on Cl(-) concentration. Excessive Cl(-) enhanced nanoparticle dissolution, whereas natural organic compound inhibited the dissolution. The dissolution data fitted well with the first-order kinetic model, and the dissolution rate coefficients were calculated using the first-order equation. This study showed the dissolution of nAg under various water conditions. The obtained results may be helpful in predicting nAg behavior in relevant environmental aquatic systems.

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