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Search Results: 1 - 10 of 21513 matches for " PENG Ran-Ran "
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Research Progress in the Electrolyte Materials for Protonic Ceramic Membrane Fuel Cells
BI Lei,TAO Ze-Tian,PENG Ran-Ran,LIU Wei
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00001
Abstract: Protonic ceramic membrane fuel cells have received great attentions because they provide an effective way to reduce the operating temperatures of solid oxide fuel cells. A brief overview of current development in protonic ceramic membrane fuel cells with high temperature proton-conducting electrolytes is given, which points out that the poor chemical stability of traditional electrolyte materials for the protonic ceramic membrane fuel cell is the main obstacle for their applications. The present development of high temperature proton conductors with high chemical stability as electrolyte materials for protonic ceramic membrane fuel cells is reviewed, as well as the influence of novel element doping strategies on the chemical stability, ionic conductivity and sinterability for BaCeO3-based materials. It also indicates the problems of high temperature proton conductors for protonic ceramic membrane fuel cells as well as their prospects.
Research Progress in the Electrolyte Materials for Protonic Ceramic Membrane Fuel Cells
质子陶瓷膜燃料电池电解质材料的研究进展

BI Lei,TAO Ze-Tian,PENG Ran-Ran,LIU Wei,
毕磊
,陶泽天,彭冉冉,刘卫

无机材料学报 , 2010,
Abstract: Protonic ceramic membrane fuel cells have received great attentions because they provide an effective way to reduce the operating temperatures of solid oxide fuel cells. A brief overview of current development in protonic ceramic membrane fuel cells with high temperature proton-conducting electrolytes is given, which points out that the poor chemical stability of traditional electrolyte materials for the protonic ceramic membrane fuel cell is the main obstacle for their applications. The present development of high temperature proton conductors with high chemical stability as electrolyte materials for protonic ceramic membrane fuel cells is reviewed, as well as the influence of novel element doping strategies on the chemical stability, ionic conductivity and sinterability for BaCeO3-based materials. It also indicates the problems of high temperature proton conductors for protonic ceramic membrane fuel cells as well as their prospects.
Specific Na+ and K+ Cation Effects on the Interfacial Water Molecules at the Air/Aqueous Salt Solution Interfaces Probed with Non-resonant Second Harmonic Generation (SHG)
Hong-tao Bian,Ran-ran Feng,Yuan Guo,Hong-fei Wang
Physics , 2008, DOI: 10.1063/1.3104609
Abstract: Here we report the polarization dependent non-resonant second harmonic generation (SHG) measurement of the interfacial water molecules at the aqueous solution of the following salts: NaF, NaCl, NaBr, KF, KCl, and KBr. Through quantitative polarization analysis of the SHG data,the orientational parameter D value and the relative surface density of the interfacial water molecules at these aqueous solution surfaces were determined. From these results we found that addition of each of the six salts caused increase of the thickness of the interfacial water layer at the surfaces to a certain extent. Noticeably, both the cations and the anions contributed to the changes, and the abilities to increase the thickness of the interfacial water layer were in the following order: KBr > NaBr > KCl > NaCl ~ NaF > KF. Since these changes can not be factorized into individual anion and cation contributions, there are possible ion pairing or association effects, especially for the NaF case. We also found that the orientational parameter D values of the interfacial water molecules changed to opposite directions for the aqueous solutions of the three sodium salts versus the aqueous solutions of the three potassium salts. These findings clearly indicated unexpected specific Na+ and K+ cation effects at the aqueous solution surface. These effects were not anticipated from the recent molecular dynamics (MD) simulation results, which concluded that the Na+ and K+ cations can be treated as small non-polarizable hard ions and they are repelled from the aqueous interfaces. These results suggest that the electrolyte aqueous solution surfaces are more complex than the currently prevalent theoretical and experimental understandings.
Spectroscopic Evidence for the Specific Na+ and K+ Interactions with the Hydrogen-bonded Water Molecules at the Electrolyte Aqueous Solution Surfaces
Ran-ran Feng,Hong-tao Bian,Yuan Guo,Hong-fei Wang*
Physics , 2008, DOI: 10.1063/1.3104610
Abstract: Sum frequency generation vibrational spectra of the water molecules at the NaF and KF aqueous solution surfaces showed significantly different spectral features and different concentration dependence. This result is the first direct observation of the cation effects of the simple alkali cations, which have been believed to be depleted from the aqueous surface, on the hydrogen bonding structure of the water molecules at the electrolyte solution surfaces. These observations may provide important clue to understand the fundamental phenomenon of ions at the air/water interface.
Polarization and Experimental Configuration Analysis of Sum Frequency Generation Vibrational Spectra of Air/Water Interface
Wei Gan,Dan Wu,Zhen Zhang,Ran-ran Feng,Hong-fei Wang
Physics , 2005, DOI: 10.1063/1.2179794
Abstract: Here we report a detailed study on spectroscopy, structure and dynamics of water molecules at air/water interface, investigated with Sum Frequency Generation Vibrational Spectroscopy (SFG-VS). Quantitative polarization and experimental configuration analysis of the SFG data in different polarizations with four sets of experimental configurations can shed new lights on our present understanding of the air/water interface. Firstly, we concluded that the motion of the interfacial water molecules can only be in a limited angular range, instead rapidly varying over a broad angular range in the vibrational relaxation time suggested previously. Secondly, because different vibrational modes of different molecular species at the interface has different symmetry properties, polarization and symmetry analysis of the SFG-VS spectral features can help assignment of the SFG-VS spectra peaks to different interfacial species. These analysis concluded that the narrow 3693cm-1 and broad 3550cm-1 peaks belong to C_ v symmetry, while the broad 3250cm-1 and 3450cm-1 peaks belong to the symmetric stretching modes with C_2v symmetry. Thus, the 3693cm-1 peak is assigned to the free OH, the 3550cm-1 peak is assigned to the single hydrogen bonded OH stretching mode, and the 3250cm-1 and 3450cm-1 peaks are assigned to interfacial water molecules as two hydrogen donors for hydrogen bonding (with C_2v symmetry), respectively. Thirdly, analysis of the SFG-VS spectra concluded that the singly hydrogen bonded water molecules at the air/water interface have their dipole vector direct almost parallel to the interface, and is with a very narrow orientational distribution. The doubly hydrogen bond donor water molecules have their dipole vector point away from the liquid phase.
儿童阅读障碍易感基因研究进展
Research advances in susceptible genes for developmental dyslexia in children

孔锐, 宋然然
KONG Rui
, SONG Ran-Ran

- , 2016, DOI: 10.7499/j.issn.1008-8830.2016.12.022
Abstract:
Research of relationship between iris clarity and human eye shooting distance
虹膜清晰程度与人眼拍摄距离对应关系研究*

YUAN Wei-qi,YANG Ran-ran,ZHANG Kai-ying,
苑玮琦
,杨冉冉,张开营

计算机应用研究 , 2011,
Abstract: The existing iris reader usually requires human eye imaging in smaller depth of filed, many users become upset because of adjusting position repeatedly when acquisition the iris images. If the shooting range can be gave, it will be convenient for the use of users. Under the condition of the human eye deviating the focus of the camera,this paper studied and established the corresponding relationship between the iris image clarity and the shooting distance between the eye and lens, and evaluated by experiments the performance of four evaluation functions being used to describe the corresponding relationship between the image clarity and the eye shooting distance. Experimental results show that when the human eyes move in 90150 mm range, the iris image clarity firstly increases to maximum gradually, then reduces gradually; when the maximal shooting range between human eyes and camera is 106132 mm, the acquired iris image clarity will be enough for the performance of the iris recognition system, thus, the steady recognition effect can also be obtained.
经典Wnt 信号通路在心脏瓣膜发育中的作用
Role of the canonical Wnt signaling pathway in heart valve development

张冉冉, 桂永浩, 王旭
ZHANG Ran-Ran
, GUI Yong-Hao, WANG Xu

- , 2015, DOI: 10.7499/j.issn.1008-8830.2015.07.026
Abstract:
An Integrated Meta-Analysis of Two Variants in HOXA1/HOXB1 and Their Effect on the Risk of Autism Spectrum Disorders
Ran-Ran Song,Li Zou,Rong Zhong,Xia-Wen Zheng,Bei-Bei Zhu,Wei Chen,Li Liu,Xiao-Ping Miao
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0025603
Abstract: HOXA1 and HOXB1 have been strongly posed as candidate genes for autism spectrum disorders (ASD) given their important role in the development of hindbrain. The A218G (rs10951154) in HOXA1 and the insertion variant in HOXB1 (nINS/INS, rs72338773) were of special interest for ASD but with inconclusive results. Thus, we conducted a meta-analysis integrating case-control and transmission/disequilibrium test (TDT) studies to clearly discern the effect of these two variants in ASD.
Correlated Responses to Bi-Directional Selection for Sheep Red Blood Cell Titer in White Leghorns
Yao-Dong Hu,Jie Wen,Mai-Qing Zheng,Ran-Ran Liu,Ji-Lan Chen,Qing Zhu,Gui-Ping Zhao
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2012.2879.2884
Abstract: Four generations of bi-directional selection for antibody response to challenge with SRBC on days 56 were completed in White Leghorn chickens. The anti-SRBC titer and other immune traits were measured in up-selected (H), down-selected (L) and Control (C) lines in each Generation (G0-G4) and reproductive traits were measured in G4. In the 4th generation, the difference in SRBC titers (measured on days 61) between the selected lines was 7.18 versus 6.10, a 17% increase in the H compared to the L lines. The heritability of SRBC titer was 0.26. The genetic correlations between anti-SRBC and IgG (0.87) and IgM (0.81) were high and those between SRBC titers and those against AI (0.56), ND (0.48) and the H/L ratio (0.58) were moderate. Immune and reproductive traits compared among the H, L and C lines in the final Generation (G4) showed that AI, ND and IgM were improved significantly (p<0.05) by selection for SRBC but the age at first lay was slightly delayed (0.48 days) in the H line. This study demonstrates that selecting for antibody response to SRBC improves other immune traits consistent with broad disease resistance of chickens.
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