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PubMed | Tianjin Normal University, Tianjin Nankai Hospital, Beijing Guodian Futong Science and Technology Development CO. and Nankai University
Type: | Journal: Colloids and surfaces. B, Biointerfaces | Year: 2015

A novel nanoparticle with multilayer core-shell architecture for cell imaging is designed and synthesized by coating a fluorescent YVO4:Eu core with a diblock copolymer, MPEG-b-PMAA. The synthesis of YVO4:Eu core, which further makes MPEG-b-PMAA-YVO4:Eu NPs adapt for cell imaging, is guided by the model determined upon the evaluation of pH and CEu%. The PMAA block attached tightly on the YVO4:Eu core forms the inner shell and the MPEG block forms the biocompatible outermost shell. Factors including reaction time, reaction temperature, CEu% and pH are optimized for the preparation of the YVO4:Eu NPs. A precise defined model is established according to analyzing the coefficients of pH and CEu% during the synthesis. The MPEG-b-PMAA-YVO4:Eu NPs, with an average diameter of 24 nm, have a tetragonal structure and demonstrate luminescence in the red region, which lies in a biological window (optical imaging). Significant enhancement in luminescence intensity by MPEG-b-PMAA-YVO4:Eu NPs formation is observed. The capping copolymer MPEG-b-PMAA improves the dispersibility of hydrophobic YVO4:Eu NPs in water, making the NPs stable under different conditions. In addition, the biocompatibility MPEG layer reduces the cytotoxicity of the nanoparticles effectively. 95% cell viability can be achieved at the NPs concentration of 800 mgL(-1) after 24h of culture. Cellular uptake of the MPEG-b-PMAA-YVO4:Eu NPs is evaluated by cell imaging assay, indicating that the NPs can be taken up rapidly and largely by cancerous or non-cancerous cells through an endocytosis mechanism.

Jing L.,Shanxi Jincheng Power Supply Company | Kong Z.,Beijing University of Posts and Telecommunications | Wang G.,Beijing Guodian Futong Science and Technology Development Co. | Zang X.,Beijing Guodian Futong Science and Technology Development Co.
2014 International Conference on Mechatronics, Electronic, Industrial and Control Engineering, MEIC 2014 | Year: 2014

The high contact resistance of the corrosion products is more likely to cause contact failure. Based on service condition and natural environment of transmission and transformation equipment, the deterioration mechanism of electrical wires was investigated from the view of corrosion. The surface morphology of specimens after corrosion is observed by stereoscopic microscope and scanning electron microscope (SEM). Chemical constitution was examined by X-ray energy spectrum. The contact resistance was measured by four-point method. The experiment results show that the corrosion is mainly electrochemical corrosion. Humidity and air pollutants are the main factors of effecting the corrosion. The corrosion products formed on the surface layer of testing specimens is loose and uneven, and easy to fall off in the role of external force. The inner corrosion layer is dense and combined closely with the substrate. The EDS analysis results there is large quantity of O and S, and Cu oxide and sulfide are probably existed. The corrosion and pollution which come from the surrounding environment can increase the static contact resistance obviously, and the maximum value can reach to about 2000mΩ. © 2014. The authors - Published by Atlantis Press.

Liu Y.,Tianjin Normal University | Hu J.,Beijing Guodian Futong Science and Technology Development Co. | Sun J.-S.,Tianjin Fishery Institute | Li Y.,Nankai University | And 4 more authors.
Talanta | Year: 2014

Interest in carbon nanotubes for detecting the presence of pathogens arises because of developments in chemical vapor deposition synthesis and progresses in biomolecular modification. Here we reported the facile synthesis of multi-walled carbon nanotubes (MWCNTs), which functioned as immuno-, magnetic, fluorescent sensors in detecting Vibrio alginolyticus (Va). The structures and properties of functionalized MWCNTs were characterized by ultraviolet (UV), Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), magnetic property measurement system (MPMS) and fluorescent spectra (FL). It was found that the functionalized MWCNTs showed: (1) low nonspecific adsorption for antibody-antigen, (2) strong interaction with antibody, and (3) high immune-magnetic activity for pathogenic cells. Further investigations revealed a strong positive linear relationship (R=0.9912) between the fluorescence intensity and the concentration of Va in the range of 9.0×102 to 1.5×106 cfu mL-1. Moreover, the relative standard deviation for 11 replicate detections of 1.0×104 cfu mL-1 Va was 2.4%, and no cross-reaction with the other four strains was found, indicating a good specificity for Va detection. These results demonstrated the remarkable advantages of the multifunctional MWCNTs, which offer great potential for the rapid, sensitive and quantitative detection of Va in fishery and environmental samples. © 2014 Elsevier B.V. All rights reserved.

Liu Y.,Tianjin Normal University | Hu J.,Beijing Guodian Futong Science and Technology Development Co. | Li Y.,Nankai University | Wei H.-P.,Tianjin Normal University | And 4 more authors.
Talanta | Year: 2015

Carbon dots capped with polyethyleneimine (CD-PEI) were synthesized and applied in selective separation and preconcentration of trace Cr(VI). Dispersed particle extraction (DPE) slurry sampling with flame atomic absorption spectrometry (FAAS) was used to selectively and sensitively determine Cr(VI) in water samples. The as-synthesized CD-PEI was confirmed by Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, elemental analysis, fluorescence and zeta potential measurement. The adsorption of Cr(VI) on CD-PEI was evaluated. Its isothermal adsorption was studied and fitted in the Langmuir model. Nearly 85% of Cr(VI) was adsorbed within 10 min showed that the CD-PEI exhibited fairly fast kinetics for the sorption of Cr(VI). Experimental conditions, including the content and size of CD-PEI, sample pH, adsorption time, sample volume, slurry volume and interfering ions, were further optimized to obtain efficient preconcentration and high-precision determination of Cr(VI). CD-PEI with small size turned to be a good candidate for the preparation of slurry. CD-PEI served not only as a promising adsorbent for separation and preconcentration of Cr, but also a signal-enhancing agent in FAAS. The method achieved an enhancement factor of 30 and a detection limit (S/N=3) of 0.21 μg L-1 Cr(VI) with a consumption of 14.0 mL sample and an adsorption time of 5 min, which provided two times of signal enhancement. The RSD for 11 replicate measurements of 5.0 μg L-1 Cr(VI) was 2.8%. The possible signal enhancement mechanism was proposed. The developed method has been applied to determine trace Cr(VI) in a variety of water samples. © 2014 Elsevier B.V. All rights reserved.

Diao S.,Key Laboratory of Special Functional Aggregated Materials | Diao S.,Shandong University | Zhang S.,Key Laboratory of Special Functional Aggregated Materials | Zhang S.,Shandong University | And 8 more authors.
Journal of Applied Polymer Science | Year: 2011

Two kinds of treated fumed silica were prepared by treatment with either tetraphenylphenyltriethoxysilane (TPHTS) or both tetraphenylphenyltriethoxysilane and hexamethyldisilazane (TPHMTS), and were used as reinforcing filler for silicone rubber. The resistance to irradiation of the silicone rubber obtained was investigated by gamma ray of dose 500 kGy in air. The mechanical properties and the average molecular weight between crosslinking points (Mc) of the silicone rubber were determined before and after irradiation. The results show that the fumed silica treated by tetraphenylphenyltriethoxysilane (TPHPHS) can effectively improve the radiation resistance of silicone rubber while the fumed silica treated by both tetraphenylphenyltriethoxysilane and hexamethyldisilazane (MMN) cannot only effectively improve the radiation resistance of silicone rubber but also has excellent reinforcing effect on silicone rubber. © 2010 Wiley Periodicals, Inc.

Wei S.J.,Changchun University of Technology | He L.,Henan University of Science and Technology | Xin W.,Beijing guodian futong science and technology development co | Miao G.,Changchun University of Technology
Applied Mechanics and Materials | Year: 2013

In this paper, the relation between angle of rotation function of the five-bar and similar four-bar mechanisms' rigid-body and Coupler Rotation-Angle function is discussed. The principles of reduce the numerical atlas are proposed. A numerical atlas database comprising 240498 basic dimensional types is set up. Make the five-bar and similar four-bar mechanism for Rigid-Body Guidance with prescribed timing possible. Finally, an example is given to prove it. © 2013 Trans Tech Publications Ltd, Switzerland.

Zhao Q.,Beijing Guodian Futong Science and Technology Development Co. | Peng X.-K.,Beijing Guodian Futong Science and Technology Development Co. | Wang R.,Beijing Guodian Futong Science and Technology Development Co.
Journal of Iron and Steel Research | Year: 2010

The Norton stress exponents were calculated based on creep test with high stresses at 595, 610, 640, 670 °C of P92 steel. The creep mechanics was clarified as dislocation creep with the values of the Norton stress exponents. And a new creep model which treated damage as an internal state variable named creep damage tolerance factor was analyzed as well. The creep and fracture mechanics was illustrated as dislocation controlled with the value of creep damage tolerance factor λ = 2. 94. The microstructure investigation show that the dislocation density decreases dramatically after creep. The change show that high density dislocations are the reason of the excellent creep rupture strength of P92 steel. With decreasing dislocation density during creep, the creep rupture strength decreases and fractured finally.

Wang J.H.,Beijing Guodian Futong Science and Technology Development CO. | Wang G.G.,Beijing Guodian Futong Science and Technology Development CO. | Zhaoc Y.J.,Beijing Guodian Futong Science and Technology Development CO.
Advanced Materials Research | Year: 2013

The effect of UV radiation and surface leakage current on the hydrophobic behavior of the RTV(room temperature vulcanized silicone rubber) silicone rubber was investigated. It's found that the ultraviolet radiation and surface leakage current both could weaken the hydrophobicity of the RTV surface in different degree. © (2013) Trans Tech Publications, Switzerland.

Wang Y.D.,Beijing Guodian Futong Science and Technology Development Co.
Computer, Intelligent Computing and Education Technology - Selected Peer Reviewed Papers From 2014 International Conference on Computer, Intelligent Computing and Education Technology, CICET 2014 | Year: 2014

By introducing the working theory of steel belt conveyor, the causes for wear condition of parts of scraper blade, chain and guide roller of running steel belt conveyor have been analyzed. Find out the optimization measure with minimum abrasion loss by corresponding optimization calculation. And through the application demonstration in a some power plant, by implementing the measures for treatment, the equipment defect could be reduced, and the operational reliability of the system could be improved. © 2014 Taylor & Francis Group, London, UK.

Beijing Guodian Futong Science and Technology Development Co. | Date: 2012-02-29

A bottom ash discharging device for a coal-fired boiler including: a clinker case, installed between a bottom ash hopper outlet of the coal-fired boiler and a bottom ash conveyer, an impact bar including a plurality of heat-resistant metal rods supporting inside the clinker case, a clinker crusher, installed above the impact bar for crushing the clinker, and a guiding device, installed between the bottom ash hopper outlet and the clinker crusher for limiting the clinker to drop into the clinker crushing area of the clinker crusher. The bottom ash discharging device ensures that the clinkers drop from the bottom ash hopper outlet to the rear area of the clinker crusher, and that the impact bar can be replaced and repaired without stopping the coal-fired boiler.

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