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Li J.,Guangzhou Huagong Motor vehicle Inspection technology Co. | Yu S.H.,Guangzhou Huagong Motor vehicle Inspection technology Co. | Zhang N.F.,Guangzhou Entry Exit Inspection And Quarantine Bureau | He H.,University of South China | And 2 more authors.
Applied Mechanics and Materials | Year: 2013

For racing application, what actually counts is the wheel path during bump and the consequently change of wheel parameters like camber. The suspension system mainly comprises of the elastic components (springs), shock absorbers and control arms. This paper covers: Firstly, the selection of the suspension type of a FSAE racecar. Secondly, how to determine the hard points of the suspension system according to the general envelop of the racecar. Then the 3D-modeling and assembly of the suspension system will be done using Autodesk Inventor; With the results from the kinetic and dynamics simulations using ADAMS, adjustments or amendments will be done to the system to optimize the change of parameters in bump and roll; At last, according to the results of the FEA processes, the structure of the control arms, uprights, rockers, etc. will be optimized so that the stress of each components within strength limitations. Finally, optimize the suspension assembly and make sure it meets the practical requirements. © (2013) Trans Tech Publications, Switzerland. Source

Liang Q.-X.,Chengdu University of Technology | Zhu X.-P.,Chengdu University of Technology | Chen W.,Chengdu University of Technology | Yin J.-X.,Guangzhou Entry Exit Inspection And Quarantine Bureau
Yejin Fenxi/Metallurgical Analysis | Year: 2011

In HAc-NaAc buffer solution at pH 4.5, phenanthroline showed a sensitive polarographic peak at -0.82V (vs. SCE). After adding vanadium, the polarographic peak was reduced. Meanwhile, the reduction of peak current had linearity to the addition amount of vanadium in the range of 0.05-5.0 μg/mL. Based on this, a new determination method of vanadium by polarography was established. The reagents and instrumental conditions were optimized. The interference of coexisting elements was investigated. Under the optimal conditions, the detection limit of vanadium was 0.0042 μg/mL. During the determination of 0.8 μg/mL vanadium (V), the coexisting elements in vanadium-titanium magnetite had no interference expect for Fe, Ti and Mn. Fe and Ti could be separated by precipitation method through controlling pH of the solution. The interference of Mn and residual Fe and Ti in solution could be eliminated by adding F-. The proposed method has been applied to the determination of vanadium in vanadium-titanium magnetite certified reference materials. The results were consistent with the certified values, and the relative standard deviations (RSD) were less than 1.1%. Source

Wang F.,Korla Entry Exit Inspection and Quarantine Bureau | Zhang X.,Xinjiang Entry exit Inspection and Quarantine Bureau | Feng J.,Zhejiang Sci-Tech University | Wang Z.,Guangzhou Entry Exit Inspection And Quarantine Bureau | Wang P.,Korla Entry Exit Inspection and Quarantine Bureau
European Food Research and Technology | Year: 2014

With the increase in number of the genetically modified (GM) crops authorized worldwide and specific labeling legislation established by many countries, a reliable and efficient method for routine screening of raw material or processed food products needs to be developed. In this paper, a quadruplex quantitative real-time PCR (qPCR) system is described which allows simultaneous detection of one tomato endogenous gene and three most frequently used transgenic elements in GM products: cauliflower mosaic virus 35S promoter, Agrobacterium tumefaciens nopaline synthase terminator, and neomycin phosphotransferase II gene. The specificities of the assays are optimized and validated. In the quadruplex qPCR system, the detection ranges for all of the four genes were determined to be 8-80,000 copies per reaction. Finally, the established detection system was applied in amplification of exogenous and endogenous genes from 33 raw materials and 35 processed products samples. The results indicate that quadruplex qPCR method is feasible for screening of GM tomato products, even for some processed food. As this detection system could be easily applied to the detection of transgenic elements in other plant species, we expect it will meet the challenges of routine GM crop detection resulting from a rapid increase in the number of GM crops in the future. © 2014 Springer-Verlag Berlin Heidelberg. Source

Wu X.,Central South University of forestry and Technology | Ding L.,China Academy of Safety Science and Technology | Xiao J.,China Academy of Safety Science and Technology | Long Y.,Guangzhou Entry Exit Inspection And Quarantine Bureau | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2011

Monodisperse magnetic submicron particles were synthesized by a solvothermal reduction method. A solid phase extraction (SPE) based on the monodisperse magnetic submicron particles and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the determination of bisphenol A (BPA) at trace level in milk has been established. The important parameters that affect the extraction efficiency such as the solution pH, dosage of magnetic submicron particles, nature of elution solution and its volume were optimized. The optimal extraction conditions were as follows1 the pH 6. 0, the dosage of 3. 5mg magnetic submicron particles and 0. 4mL methanol as elution solution. BPA was analyzed by HPLC-MS/MS in negative ion mode using an Agilent XDB C 18 column as analytical column. Under the optimal conditions, the calibration curves showed a good linearity in the BPA con-centration range of 1.0 - 100.0μg/L. The correlation coefficient was 0.999 3. The average recoveries of BPA at three spiked levels ranged from 85. 3% to 96. 1% with the relative standard deviations (RSDs) less than 10%. The detection limit of the method was 1. 0μg/L. The method is sensitive, simple, and suitable for the rapid determination of BPA in milk. Source

Liang Q.-X.,Chengdu University of Technology | Zhu X.-P.,Chengdu University of Technology | Yin J.-X.,Guangzhou Entry Exit Inspection And Quarantine Bureau
Yejin Fenxi/Metallurgical Analysis | Year: 2010

A microwave digestion method was established for vanadium-titanium magnetite samples under a mixed system of sulfuric acid and phosphoric acid. The dissolving conditions were optimized: 0.2000g of sample was added with 3 mL of H2SO4, 9 mL of H3PO4, and 5 drops of HNO3, which was heated continuously for 2 min at 350 W, 6 min at 560 W and another 2 min at 350 W. After dissolution, Ti and Fe were successively titrated with K2Cr2O7 solutions of two different concentrations with neutral red and diphenylamine sulfonate as indicators. Through 5 parallel determinations of Fe and Ti in vanadium-titanium magnetite samples (Concentrate ore 2 #), it was obtained that the relative errors were 0.26% and-0.57%, respectively, and the relative standard deviations were 0.12% and 0.25%. Source

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