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Hengjingqiao, China

Zhou Y.,Yunnan University | Zhu J.,Honghe College
Proceedings - 2010 WASE International Conference on Information Engineering, ICIE 2010 | Year: 2010

The efficiency of a solar panel is related to the amount of solar energy it acquired, so it is necessary for the panel to track the sun's position accurately. A microcontroller-based sun tracking system is proposed in this paper, which is comprised of a sensor, a microcontroller, and two stepper motors. The solar sensor is a four-quadrant type with four photodiodes, and is used for the direction determination of the sun. The fuzzy logic control approach is developed in the microcontroller to drive the stepper motors. By implementation of the tracking system, the solar panel can be perpendicular to the light beam at any moment so as to obtain the maximum solar radiation. The experimental results illustrate that the proposed system can increase the output power of the solar panel significantly. © 2010 IEEE.

Zhou Y.,Yunnan University | Zhu J.,Honghe College
Proceedings of the 2010 2nd International Conference on Future Computer and Communication, ICFCC 2010 | Year: 2010

A wireless sensor network which consists of SpO2 sensor devices, a router, and Personal Area Network (PAN) coordinators was proposed in this paper. These devices of the network are all developed on ZigBee module which consists of a MCU (MSP430F1611) and a ZigBee chip (CC2320). The sensor devices measure the SpO2 data from patients and transmit it to the router. The router schedule a sending time for each associated device and use hierarchical routing to forward data to a specific device. The PAN coordinator extracts the received packages and passes them to the personal computer. A web-based management method is used to manage the physiological signals which can be displayed on the web page. The system can collect sensitive health information remotely and has a good applied prospect in remote healthy hare field. ©2010 IEEE.

Zhou Y.,Yunnan University | Zhu J.,Honghe College
Proceedings - 2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010 | Year: 2010

A ZigBee based personal dynamic positioning method via particle filter is discussed in this paper. The Received Signal Strength (RSS) is adopted to estimate the location of the target by applying the trilateration algorithm. The simplified path loss model is chosen to represent the signal propagation. The weights of particles are determined by the distance between the predicted position and the calculated position at the next time, and restrained by the personal average walking velocity. A Zig8ee sensor network that includes reference nodes, end device, router, and coordinator is constructed to verify the proposed algorithm. Two experiments have been taken to test the positioning effect, and the results show that the particle filter is available for tracking in the ZigBee based wireless network. © 2010 IEEE.

Wen S.-H.,Nanchang University | Cui S.-G.,Nanchang University | Shi L.,Honghe College | Liang R.-P.,Nanchang University | Qiu J.-D.,Nanchang University
Journal of Electroanalytical Chemistry | Year: 2015

A novel approach to the synthesis of mono-dispersed platinum nanoparticles (Pt NPs) on multiwalled carbon nanotubes (MWNTs) has been proposed. With this method, we successfully assembled mono-dispersed Pt NPs on MWNTs. The method involved the in situ high-temperature decomposition of the precursor, platinum (II) acetylacetonate (Pt(acac)2), in liquid polyols. We used X-ray diffraction, scanning electron microscopy, and transmission electron microscopy to characterize the resulting MWNTs covered with Pt NPs (Pt@MWNTs). We found that the size of the Pt NPs and the coverage density on MWNTs could be tuned easily by changing the reaction temperature and the initial mass ratio of Pt(acac)2 to MWNTs. Electrocatalytic measurements showed that the Pt@MWNTs had excellent catalytic activities in the electrooxidation of methanol and in the oxygen reduction reaction. These Pt@MWNTs have potential applications in fuel cells and biosensors. © 2014 Elsevier B.V. All rights reserved.

Wu N.,Honghe College | Liu W.,Honghe College | Yan H.-P.,Honghe College | Fan A.-P.,Honghe College | And 5 more authors.
Yaoxue Xuebao | Year: 2013

Two sample pretreatment methods of pesticide residues in Panax notoginseng of Chinese traditional medicine were developed. For Method I, the residues were extracted from homogenized tissue with n-hexane-dichloromethane (6:4) by means of ultrasonication, the crude extract was purified by an Envi-carb/NH 2 solid-phase extraction (SPE) column. For Method II, matrix solid-phase dispersion (MSPD) technique was used for extracting and cleaning up. The eluates were concentrated by rotary evaporation, and then were redissolved in dichloromethane prior to GC-MS determination. The determination was performed in selected ion monitoring (SIM) mode with the external calibration for quantitative analysis. Under the optimal conditions, the results indicated that the methods are easier and faster, the recoveries of method I for the spiked standards at concentration of 0.01, 0.5, and 2.0 mg·kg-1 were 81.90%-102.10% with the relative standard deviations (RSDs) of 3.60%-7.10%. The recoveries of method II were 96.26%-104.20% with the RSDs of 3.52%-7.94%. The detection limits (S/N) for residues of pesticides were in the range of 0.48-1.34 ng·g-1. The results indicated that these multiresidue analysis methods can meet the requirements for determination of residue pesticides and can be appropriate for trace analysis of residue pesticides in Panax notoginseng.

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