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Cheng S.,South China Normal University | Yuan Z.,South China Normal University | Ye X.,National Testing Center for Optical Radiation Safety of Photoelectric Products | Zhang F.,EVE Energy Co. | Liu J.,EVE Energy Co.
Microelectronics Reliability | Year: 2015

The empirical prediction model of residual capacity (Cap) for D-size Li/SOCl2 cells has been developed and validated based on the accelerated degradation test (ADT) data. In this experiment, a series of constant storage temperatures (25°C, 55°C, 70°C, and 85°C) was selected and the residual capacity of each cell was monitored continuously during the aging test. The model was established by fitting twice. Firstly, time dependence of Cap (t, T) was investigated. Secondly, the generalized model of residual capacity was built. The prediction model, as a function of storage time and temperature, can precisely predict the value of residual capacity. The generalized empirical model of Cap, involving two aging processes, is valid for the degradation condition of temperatures from 25 °C to 70 °C. The first aging process completed rapidly within 7 days. The second aging process was accelerated by temperature with time1/2 kinetics. For the cells stored at 85 °C, another failure mechanism may exist based on the departure of linear fitting coefficients. © 2014 Elsevier Ltd. All rights reserved. Source

Qiu X.,South China Normal University | Xiong K.,Southern Medical University | Ye X.,National Testing Center for Optical Radiation Safety of Photoelectric Products | Huang Z.,Guzhen Productivity Promotion Center | And 5 more authors.
Scanning | Year: 2015

Confocal micro-Raman spectroscopy was used to distinguish human xanthelasma skin (HXS) from the human normal skin (HNS). Results showed that intensive Raman peaks at 1,269, 1,336, 1,448, and 1,656 cm-1 increased obviously. Both 1,269 and 1,656 cm-1 peaks showed that the proteins in HXS were mostly in the anti-parallel ß sheet conformation. While the intensities of bands at 1,032, 1,087, 1,300, and 1,448 cm-1 belonged to lipids were enhanced in HXS spectrum compared to those in HNS spectrum. There were main intercellular lipids alkyl chains with minor proteins contribution at 1,087 cm-1 and phenylalanine at 1,032 cm-1. To quantitative analysis of the difference, the ratio of I852/I829 was calculated, which was 1:1.04 ± 0.04 and 1:1.11 ± 0.02 for HNS and HXS (p < 0.01), respectively. The data indicated that some tyrosine residues, which form a hydrogen bond with H2O prior to aggregation, were captured by strong hydrogen-bond acceptors in the aggregate. The decreased ratio of I852/I829 indicated more hydrophobic in HXS than HNS. Principal component analysis showed a one-to-one relationship between human xanthelasma skin and the corresponding Raman spectra. It could be given useful help for the diagnostication of xanthelasma. SCANNING 37:307-312, 2015. © 2015 Wiley Periodicals, Inc. © Wiley Periodicals, Inc. Source

Zhou F.,South China Normal University | Wei H.,South China Normal University | Ye X.,National Testing Center for Optical Radiation Safety of Photoelectric Products | Hu K.,National Testing Center for Optical Radiation Safety of Photoelectric Products | And 5 more authors.
Physics in Medicine and Biology | Year: 2015

In this work, the potential use of nanoparticles as contrast agents by using spectral domain optical coherence tomography (SD-OCT) in liver tissue was demonstrated. Gold nanoparticles (average size of 25 and 70 nm), were studied in human normal and cancerous liver tissues in vitro, respectively. Each sample was monitored with SD-OCT functional imaging for 240 min. Continuous OCT monitoring showed that, after application of gold nanoparticles, the OCT signal intensities of normal liver and cancerous liver tissue both increase with time, and the larger nanoparticles tend to produce a greater signal enhancement in the same type of tissue. The results show that the values of attenuation coefficients have significant differences between normal liver tissue and cancerous liver tissue. In addition, 25 nm gold nanoparticles allow higher penetration depth than 70 nm gold nanoparticles in liver tissues. © 2015 Institute of Physics and Engineering in Medicine. Source

Zhu M.F.,South China Normal University | Ye X.P.,National Testing Center for Optical Radiation Safety of Photoelectric Products | Huang Y.Y.,South China Normal University | Guo Z.Y.,South China Normal University | And 2 more authors.
Scanning | Year: 2014

Raman spectroscopy has been shown to have the potential for revealing oxygenated and spin ability of hemoglobin. In this study, confocal micro- Raman spectroscopy is developed to monitor the effect of sodium nitrite on oxyhemoglobin (HbO2) in whole blood. We observe that the band at 1,638 cm-1 which is sensitive to the oxidation state decreases dramatically, while the 1,586 cm-1 (low-spin state band) reduces both in methemoglobin (MetHb) and poisoning blood. Our results show that adding in sodium nitrite lead to the transition from HbO2 (Fe2+) to MetHb (Fe3+) in whole blood, and the iron atom converts from the low spin state to the high spin state with a delocalization from porphyrin plane. Moreover, multivariate statistical techniques, including principal components analysis (PCA) and linear discriminant analysis (LDA) are employed to develop effective diagnostic algorithms for classification of spectra between pure blood and poisoning blood. The diagnostic algorithms based on PCA-LDA yield a diagnostic sensitivity of 100% and specificity of 100% for separating poisoning blood from normal blood. Receiver operating characteristic (ROC) curve further confirms the effectiveness of the diagnostic algorithm based on PCA-LDA technique. The results from this study demonstrate that Raman spectroscopy combined with PCA-LDA algorithms has tremendous potential for the non-invasive detection of nitrite poisoning blood. © 2014 Wiley Periodicals, Inc. Source

Wang X.,South China Normal University | Liu Z.,South China Normal University | Ye X.,National Testing Center for Optical Radiation Safety of Photoelectric Products | Hu K.,National Testing Center for Optical Radiation Safety of Photoelectric Products | And 4 more authors.
Applied Surface Science | Year: 2014

Herein, we used a facile method mainly through self-assemble, hydrogen bonding and electrostatic interaction to synthesize poly(diallyldimethylammonium chloride)/graphene oxide (PDDA/GO) hydrogels, which can be easily used as adsorbents to eliminate anionic dyes. The as-prepared PDDA/GO hydrogels were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. In order to research the adsorption kinetics for the removal of anion dyes from water pollution, we further investigated that the effect of concentration, temperature, pH, ionic strength or cycle number on the removal process. The results indicated that due to the strong π-π stacking and anion-cation interaction, there were high removal efficiencies for both ponceau S (PS) and trypan blue (TB). The equilibrium time of adsorption is 30 min and 120 min for PS and TB, respectively, at which the solution could be decolorized to nearly colorless. Meanwhile, the adsorption process was more according with the pseudo-second-order model than the pseudo-first-order model. The hydrogels exhibited high removal efficiency for those two anionic dyes after four repeated adsorption and desorption treatments. It was demonstrated that PDDA/GO hydrogels would have great potential as a freestanding and reusable adsorbent for the practical application in water purification. © 2014 Elsevier B.V. Source

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