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| 1 | Nondestructive Testing and Characterization of Residual Stress Field Using an Ultrasonic Method显示文摘To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel(12%C) as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave(LCR wave) is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designed to conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening. | SONG Wentao XU Chunguang PAN Qinxue SONG Jianfeng | 2016 | Chinese Journal of Mechanical Engineering2016,29,2: | 27 |
| 2 | Effect of Hot Isostatic Pressing Conditions and Cooling Rate on Microstructure and Properties of Ti-6Al-4V Alloy from Atomized Powder显示文摘The effects of temperature and pressure on density, microstructure and mechanical properties of powder compacts during hot isostatic pressing(HIPping) were investigated. Optimized HIPping parameters of temperature range from 900 to 940℃, pressure over 100 MPa and holding time of 3 h, were obtained. Tensile properties after different heat treatments show that both the geometry of samples and cooling rate have a significant influence on mechanical properties. Finite element method was used to predict the temperature field distribution during HIPped sample cooling, and the experimental results are in agreement with simulation prediction. The interaction of HIPping parameters was analyzed based on the response surface methodology(RSM) in this study. | Lei Xu Ruipeng Guo Chunguang Bai Jiafeng Lei Rui Yang | 2014 | Journal of Materials Science & Technology2014,30,12: | 24 |
| 3 | Microbiologically influenced corrosion behavior of S32654 super austenitic stainless steel in the presence of marine Pseudomonas aeruginosa biofilm显示文摘S32654 super austenitic stainless steel(SASS) is widely used in highly corrosive environments. However,its microbiologically influenced corrosion(MIC) behavior has not been reported yet. In this study, the corrosion behavior of S32654 SASS caused by a corrosive marine bacterium Pseudomonas aeruginosa was investigated using electrochemical measurements and surface analysis techniques. It was found that P. aeruginosa biofilm accelerated the corrosion rate of S325654 SASS, which was demonstrated by a negative shift of the open circuit potential(EOCP), a decrease of polarization resistance and an increase of corrosion current density in the culture medium. The largest pit depth of the coupons exposed in the P.aeruginosa broth for 14 days was 2.83 m, much deeper than that of the control(1.33 m) in the abiotic culture medium. It was likely that the P. aeruginosa biofilm catalyzed the formation of CrO_3, which was detrimental to the passive film, resulting in MIC pitting corrosion. | Huabing Li Chuntian Yang Enze Zhou Chunguang Yang Hao Feng Zhouhua Jiang Dake Xu Tingyue Gu Ke Yang | 2017 | Journal of Materials Science & Technology2017,33,12: | 10 |
| 4 | Flow behavior and processing map for hot deformation of ATI425 titanium alloy显示文摘Flow behavior and processing map play important roles in the hot deformation process of titanium alloys. In this research, compression Gleeble tests have been carried out to investigate the stress–strain relationship at temperatures ranging from 700 to 1000℃ and strain rates ranging from 0.001 to 1 s^(-1) for ATI 425 titanium alloy. Arrhenius type constitutive equation was obtained to describe the compressive flow behavior with modification of additional deformation dead zone, friction model, temperature model and strain rate. The introduction of novel calculation method for value in Arrhenius equation gives more accurate fitting than traditional one. Processing maps were drawn based on the distribution of dissipator co-content, and optimized deformation temperature and strain rate range obtained. It is proven to be accurate and effective through the experimental results. The microstructure analysis shows that more dynamic recrystallization can be achieved in the area with larger value on the processing map. | Qinggang Meng Chunguang Bai Dongsheng Xu | 2018 | Journal of Materials Science & Technology2018,34,4: | 8 |
| 5 | Mutation of kri1l causes definitive hematopoiesis failure via PERK-dependent excessive autophagy induction显示文摘 | Xiao-E Jia Ke Ma Tao Xu Lei Gao Shuang Wu Cong Fu Wenjuan Zhang Zhizhang Wang Kaiyu Liu Mei Dong Changbin Jing Chunguang Ren Zhiwei Dong Yi Chen Yi Jin Qiuhua Huang Xing Chang Min Deng Li Li Lingfei Luo Jun Zhu Yongjun Dang Hung-Chun Chang Leonard I Zon Yi Zhou Saijuan Chen Weijun Pan | 2015 | Cell Research2015,25,8: | 8 |
| 6 | Microbiologically influenced corrosion of titanium caused by aerobic marine bacterium Pseudomonas aeruginosa显示文摘Microbiologically influenced corrosion(MIC) is a big threat to the strength and safety of many metallic materials used in different environments throughout the world. The metabolites and bioactivity of the microorganisms cause severe deterioration on the metals. In this study, MIC of pure titanium(Ti) was studied in the presence of a highly corrosive aerobic marine bacterium Pseudomonas aeruginosa. The results obtained from electrochemical test showed that Ti was corrosion resistant in the abiotic culture medium after 14 d, while the increased corrosion current density(i_(corr)) obtained from polarization curves and the decreased charge transfer resistance(R_(ct)) from electrochemical impedance spectroscopy(EIS)indicated the accelerated corrosion of Ti caused by P. aeruginosa biofilm. For further confirmation of the above results, the surface of Ti was investigated using scanning electron microscopy(SEM), confocal laser scanning microscopy(CLSM) and X-ray photoelectron spectroscopy(XPS). According to the XPS results, TiO_2 was formed in both abiotic and biotic conditions, while unstable oxide Ti_2O_3 was detected in the presence of P. aeruginosa, leading to the defects in the passive film and localized corrosion. Pitting corrosion was investigated with the help of CLSM, and the largest pit depth found on Ti surface immersed in P. aeruginosa was 1.2 μm. Ti was not immune to MIC caused by P. aeruginosa. | M.Saleem Khan Zhong Li Ke Yang Dake Xu Chunguang Yang Dan Liu Yassir Lekbach Enze Zhou Phuri Kalnaowakul | 2019 | Journal of Materials Science & Technology2019,35,1: | 8 |
| 7 | Microbial corrosion resistance of a novel Cu-bearing pipeline steel显示文摘Microbiologically influenced corrosion(MIC) is becoming a serious problem for buried pipelines. Developing environmentally friendly strategies for MIC control is increasingly urgent in oil/gas pipeline industry.Copper(Cu) in steels can not only provide aging precipitation strengthening, but also kill bacterium,offering a special biofunction to steels. Based on the chemical composition of traditional X80 pipeline steel, two Cu-bearing pipeline steels(1% Cu and 2% Cu) were fabricated in this study. The microstructure,mechanical properties and antibacterial property against sulphate-reducing bacteria(SRB) and Pseudomonas aeruginosa(P. aeruginosa) were studied. It was found that the novel pipeline steel alloyed by 1%Cu exhibited acicular ferrite microstructure with nano-sized Cu-rich precipitates distribution in the matrix, resulting in better mechanical properties than the traditional X80 steel, and showed good MIC resistance as well. The pitting corrosion resistance of 1% Cu steel in as-aged condition was significantly better than that of X80 steel. A possible antibacterial mechanism of the Cu-bearing pipeline steel was proposed. | Xianbo Shi Wei Yan Dake Xu Maocheng Yan Chunguang Yang Yiyin Shan Ke Yang | 2018 | Journal of Materials Science & Technology2018,34,12: | 7 |
| 8 | Investigation on the fabrication of lightweight aggregate with acid-leaching tailings of vanadium-bearing stone coal minerals and red mud显示文摘Proper treatment of acidleaching tailings(ALTs)of vanadiumbearing stone coal minerals is of great urgency.One approach is adding it into the raw materials during the preparation of lightweight aggregate(LWA).But clay is always needed.In this paper,another solid waste,red mud,was mixed with ALTs as a source of flux components instead of clay.Evaluation of the physical characteristics,morphological structures,as well as crystal phases during the sintering process were investigated.When their mixtures with a proper ratio were sintered at 1080℃,a glassy phase with certain viscosity was formed,and the gases generated simultaneously were encapsulated by the melt.Finally,LWA with a onehour water absorption as low as 1.46%,a bulk density as low as 728.76 kgm 3 and a compressive strength as high as 10.77 MPa was fabricated. | Chunguang Song Hongling Zhang Yuming Dong Lili Pei Honghui Liu Junsheng Jiang Hongbin Xu | 2021 | Chinese Journal of Chemical Engineering2021,34,4: | 6 |
| 9 | Automatic Method for Synchronizing Workpiece Frames in Twin-robot Nondestructive Testing System显示文摘The workpiece frames relative to each robot base frame should be known in advance for the proper operation of twin-robot nondestructive testing system. However, when two robots are separated from the workpieces, the twin robots cannot reach the same point to complete the process of workpiece frame positioning. Thus, a new method is proposed to solve the problem of coincidence between workpiece frames. Transformation between two robot base frames is initiated by measuring the coordinate values of three non-collinear calibration points. The relationship between the workpiece frame and that of the slave robot base frame is then determined according to the known transformation of two robot base frames, as well as the relationship between the workpiece frame and that of the master robot base frame. Only one robot is required to actually measure the coordinate values of the calibration points on the workpiece. This requirement is beneficial when one of the robots cannot reach and measure the calibration points. The coordinate values of the calibration points are derived by driving the robot hand to the points and recording the values of top center point(TCP) coordinates. The translation and rotation matrices relate either the two robot base frames or the workpiece and master robot. The coordinated are solved using the measured values of the calibration points according to the Cartesian transformation principle. An optimal method is developed based on exponential mapping of Lie algebra to ensure that the rotation matrix is orthogonal. Experimental results show that this method involves fewer steps, offers significant advantages in terms of operation and time-saving. A method used to synchronize workpiece frames in twin-robot system automatically is presented. | LU Zongxing XU Chunguang PAN Qinxue MENG Fanwu LI Xinliang | 2015 | Chinese Journal of Mechanical Engineering2015,28,4: | 6 |
| 10 | Effect of Cu Addition to 2205 Duplex Stainless Steel on the Resistance against Pitting Corrosion by the Pseudomonas aeruginosa Biofilm显示文摘The effect of copper addition to 2205 duplex stainless steel(DSS) on its resistance against pitting corrosion by the Pseudomonas aeruginosa biofilm was investigated using electrochemical and surface analysis techniques. Cu addition decreased the general corrosion resistance, resulting in a higher general corrosion rate in the sterile medium. Because DSS usually has a very small general corrosion rate, its pitting corrosion resistance is far more important. In this work, it was shown that 2205-3%Cu DSS exhibited a much higher pitting corrosion resistance against the P. aeruginosa biofilm compared with the 2205 DSS control, characterized by no significant change in the pitting potential and critical pitting temperature(CPT) values. The strong pitting resistance ability of 2205-3%Cu DSS could be attributed to the copper-rich phases on the surface and the release of copper ions, providing a strong antibacterial ability that inhibited the attachment and growth of the corrosive P. aeruginosa biofilm. | Ping Li Yang Zhao Yuzhi Liu Ying Zhao Dake Xu Chunguang Yang Tao Zhang Tingyue Gu Ke Yang | 2017 | Journal of Materials Science & Technology2017,33,7: | 5 |
| 11 | Partial melting and crust-mantle interaction in subduction channels:Constraints from experimental petrology显示文摘It is proposed in the subduction channel model that the plate interface interaction is a basic mechanism for the mass and energy exchange between Earth’s surface and interior.The significant difference in composition and nature between continental lithosphere and oceanic lithosphere inevitably leads to variations in deep physical and chemical processes as well as crust-mantle interaction products in these two settings.Many studies of experimental petrology have provided constraints on the potential partial melting and crust-mantle interaction in oceanic subduction channels for silicate and carbonate rocks.The partial melts of mafic and felsic compositions are adakitic or non-adakitic granitic melts depending on melting pressure or depth.A trivial amount of CO2 can lower significantly the melting temperature of peridotites and lead to pronounced enrichment of incompatible elements in carbonate melt.The silica saturated or unsaturated melts can react with mantle-wedge peridotites in subduction channels to generate complex products.However,the existing experiments are mostly dedicated to island arc settings above oceanic subduction zones rather than dehydration melting above continental subduction zones.It is crucial to conduct high pressure and high temperature experiments to investigate all possible reactions between peridotites and crustal materials and their derivatives under the conditions responsible for the slab-mantle interface in continental subduction channels.Experimental results,combined with natural observations,are possible to elucidate the processes of metamorphic dehydration,partial melting and mantle metasomatism in continental subduction channels. | ZHANG JunFeng WANG ChunGuang XU HaiJin WANG Chao XU WenLiang | 2015 | Science China Earth Sciences2015,58,10: | 4 |
| 12 | Experimental studies of melt-peridotite reactions at 1–2 GPa and 1250–1400°C and their implications for transforming the nature of lithospheric mantle and for high-Mg signatures in adakitic rocks显示文摘Experiments of the melt-peridotite reaction at pressures of 1 and 2 GPa and temperatures of 1250–1400°C have been carried out to understand the nature of the peridotite xenoliths in the Mesozoic high-Mg diorites and basalts of the North China Craton,and further to elucidate the processes in which the Mesozoic lithospheric mantle in this region was transformed.We used Fuxin alkali basalt,Feixian alkali basalt,and Xu-Huai hornblende-garnet pyroxenite as starting materials for the reacting melts,and lherzolite xenoliths and synthesized harzburgite as starting materials for the lithospheric mantle.The experimental results indicate that:(1)the reactions between basaltic melts and lherzolite and harzburgite at 1–2 GPa and 1300–1400°C tended to dissolve pyroxene and precipitate low-Mg#olivine(Mg#=83.6–89.3),forming sequences of dunite-lherzolite(D-L)and duniteharzburgite(D-H),respectively;(2)reactions between hornblende-garnet pyroxenite and lherzolite at 1 GPa and 1250°C formed a D-H sequence,whereas reactions at 2 GPa and 1350°C formed orthopyroxenite layers and lherzolite;and(3)the reaction between a partial melt of hornblende-garnet pyroxenite and harzburgite resulted in a layer of orthopyroxenite at the boundary of the pyroxenite and harzburgite.The reacted melts have higher MgO abundances than the starting melts,demonstrating that the melt-peridotite reactions are responsible for the high-Mg#signatures of andesites or adakitic rocks.Our experimental results support the proposition that the abundant peridotite and pyroxenite xenoliths in western Shandong and the southern Taihang Mountains might have experienced multiple modifications in reaction to a variety of melts.We suggest that melt-peridotite reactions played important roles in transforming the nature of the Mesozoic lithospheric mantle in the region of the North China Craton. | YU Yang XU WenLiang WANG ChunGuang | 2014 | Science China Earth Sciences2014,57,3: | 4 |
| 13 | Enhanced resistance of 2205 Cu-bearing duplex stainless steel towards microbiologically influenced corrosion by marine aerobic Pseudomonas aeruginosa biofilms显示文摘An antibacterial 2205-Cu duplex stainless steel(DSS)was shown to inhibit the formation and growth of corrosive marine biofilms by direct contact with copper-rich phases and the release of Cu^(2+)ions from the2205-Cu DSS surface.In this work,the microbiologically influenced corrosion(MIC)resistance of 2205-Cu DSS in the presence of the corrosive marine bacterium Pseudomonas aeruginosa was investigated.The addition of copper improved the mechanical properties such as the yield strength,the tensile strength and the hardness of 2205 DSS.Electrochemical test results from linear polarization resistance(LPR),electrochemical impedance spectroscopy(EIS)and critical pitting temperature(CPT)measurements showed that 2205-Cu DSS possessed a larger polarization resistance(R_p),charge transfer resistance(R_(ct))and CPT values,indicating the excellent MIC resistance of 2205-Cu DSS against the corrosive P.aeruginosa biofilm.The live/dead staining results and the SEM images of biofilm confirmed the strong antibacterial ability of 2205-Cu DSS.The largest pit depth of 2205-Cu DSS was considerably smaller than that of 2205 DSS after 14 d in the presence of P.aeruginosa(2.2μm vs 12.5μm).2205-Cu DSS possessed a superior MIC resistance to regular 2205 DSS in the presence of aerobic P.aeruginosa. | Dake Xu Enze Zhou Ying Zhao Huabing Li Zhiyong Liu Dawei Zhang Chunguang Yang Hai Lin Xiaogang Li Ke Yang | 2018 | Journal of Materials Science & Technology2018,34,8: | 4 |
| 14 | Photoluminescence Properties of Er-doped SiC Thin Film显示文摘 | Bian Liufang Zhang Chunguang Chen Weide Xu Zhenjia Qu Yuhua Diao Hongwei | 2006 | Journal of Rare Earths2006,24,4: | 3 |
| 15 | Two new species of Ectopleura from the Taiwan Strait,China (Cnidaria,Hydroidomedusae)显示文摘Two new species of genus Ectopleura,i.e.,Ectopleura elongata sp.nov.and E.triangularis sp.nov.are described in the present paper based on type specimens from the Taiwan Strait.The types are deposited in the Third Institute of Oceanography,State Oceanic Administration,Xiamen,China. | LIN Mao XU Zhenzu HUANG Jiaqi WANG Chunguang | 2010 | Acta Oceanologica Sinica2010,29,2: | 3 |
| 16 | High-Resolution Mesoscale Analysis Data from the South China Heavy Rainfall Experiment (SCHeREX): Data Generation and Quality Evaluation显示文摘In this study, the observational data acquired in the South China Heavy Rainfall Experiment (SCHeREX) from May to July 2008 and 2009 were integrated and assimilated with the US National Oceanic and Atmospheric Administration's (NOAA) Local Analysis and Prediction System (LAPS; information available online at http://gffzzc2aa3fc9434744efhnxcv9bw0c0qc6owp.ffgz.tsg.suse.edu.cn). A high-resolution mesoscale analysis dataset was then generated at a spatial resolution of 5 km and a temporal resolution of 3 h in four observational areas: South China, Central China, Jianghuai area, and Yangtze River Delta area. The quality of this dataset was evaluated as follows. First, the dataset was qualitatively compared with radar reflectivity and TBB image for specific heavy rainfall events so as to examine its capability in reproduction of mesoscale systems. The results show that the SCHeREX analysis dataset has a strong capability in capturing severe mesoscale convective systems. Second, the mean deviation and root mean square error of the SCHeREX mesoscale analysis fields were analyzed and compared with radiosonde data. The results reveal that the errors of geopotential height, temperature, relative humidity, and wind of the SCHeREX analysis were within the acceptable range of observation errors. In particular, the average error was 45 m for geopotential height between 700 and 925 hPa, 1.0-1.1°C for temperature, less than 20% for relative humidity, 1.5-2.0 m s-1 for wind speed, and 20-25° for wind direction. The above results clearly indicate that the SCHeREX mesoscale analysis dataset is of high quality and sufficient reliability, and it is applicable to refined mesoscale weather studies. | NI Yunqi CUI Chunguang LI Hongli PENG Juxiang QIU Xuexing ZHANG Yanxia XU Xiaolin GAO Mei JIE Lianshu ZHANG Wenhua | 2011 | Acta meteorologica Sinica2011,25,4: | 2 |
| 17 | Taxonomic notes on Hydroidomedusae (Cnidaria) from South China Sea Ⅲ: Family Rathkeidae and Zancleopsidae显示文摘This study reviews all South China Sea species belonging to the families Rathkeidae and Zancleopsidae.Morphological characters of Lizzia blondina Forbes,1848(formerly recorded as Podocoryne/Hydractinia minuta),L.gracilis(Mayer,1900),L.octostyla(Haeckel,1879) and Podocorynoides minima(Trinci,1903) (formerly recorded as Podocoryne/Hydractinia minima) are redescribed.One new species,Zancleopsis oblongus Xu,Huang & Wang,sp.nov.from South China Sea,is described and illustrated.The keys to all medusa genera of Rathkeidae and Zancleopsidae and to all species of Zancleopsis are presented.The type specimen is deposited in the Third Institute of Oceanography,State Oceanic Administration,China. | Chunguang Wang Zhenzu Xu Jiaqi Huang Donghui Guo Mao Lin Zhen Xia | 2016 | Zoological Systematics2016,41,4: | 2 |
| 18 | Corrosion Inhibition of X80 Steel in Simulated Marine Environment with Marinobacter aquaeolei显示文摘In the present study, a novel bacterium( Marinobacter aquaeolei) was examined for its corrosion inhibiting behaviour against X80 pipeline steel. Electrochemical results showed that X80 steel immersed in the solution inoculated with M. aquaeolei possessed very high corrosion resistance compared to that of abiotic control. Besides, scanning electron microscopy, confocal laser scanning microscopy and energy-dispersive X-ray spectroscopy were employed to analyse the corrosion product and the biofi lm formed on the metal surface. Fourier-transform infrared spectroscopy was also applied to determine the composition of extracellular polymeric substances(EPS). Above results indicated that the corrosion inhibition effciency observed in biotic medium was very high(91%), proving that M. aquaeolei was an effective inhibitive agent for the corrosion of carbon steel. The inhibition was credited to the formation of bacterial biofi lm and the compact protective layer of the secreted EPS. Thus, this study will introduce a natural, environmentally friendly and cost-effective system for the corrosion control of the carbon steel. | M.Saleem Khan Dake Xu Dan Liu Yassir Lekbach Ke Yang Chunguang Yang | 2019 | Acta Metallurgica Sinica(English Letters)2019,32,11: | 2 |
| 19 | Effects of heating rate on the alloy element partitioning and mechanical properties in equiaxedα+βTi-6Al-4V alloy显示文摘The effects of heating rate on the alloy element partitioning and mechanical properties during the phase transformation ofα→βin Ti-6Al-4 V alloy under solution treatment have been investigated by the experiments and phase field simulations,which reveal the evolutions of microstructure and compositions at the non-equilibrium state and well verify the experimental results.The specific results indicate that the compositions measured through electron probe micro-analysis(EPMA)under a lower heating rate are close to the equilibrium ones corresponding to the solution temperature.Heating up to the target solution temperature,as the heating rate increases,the Al content decreases and V increases in the primaryα(α_(p))grain with a larger size,the volume fraction ofα_(p)increases and the composition gradient betweenα_(p)andβphases gets steeper.The interrelated relationship among the diffusion,compositions,solution temperature and free energy of the system has been discussed in detail.Moreover,increasing the heating rate(~20.0 K/min)may help to improve the mechanical properties of the alloy by mainly adjusting theα_(p)/β;volume fractions,α_(p)particle size and secondaryα(α_(p))size during the process of heating up to the solution temperature.These results may shed some light on the optimization of the knowledge-based heat treatment route. | Jinhu Zhang Hongtao Ju Haisheng Xu Liang Yang Zhichao Meng Chen Liu Ping Sun Jianke Qiu Chunguang Bai Dongsheng Xu Rui Yang | 2021 | Journal of Materials Science & Technology2021,,35: | 2 |
| 20 | Targeted thrombolysis strategies for neuroprotective effect显示文摘Stroke is usually treated by systemic thrombolytic therapy if the patient presents within an appropriate time window. There is also widespread interest in the development of thrombolytic agents that can be used in cases of delayed presentation. Current agents that can be used in cases of delayed presentation of nerve damage by thrombus. Current systemic thrombolytic therapy is associated with adverse effects such as fibrinogenolysis and bleeding. In an attempt to increase the efficacy, safety, and specificity of thrombolytic therapy, a number of targeted thrombolytic agents have been studied in recent years. This review focuses on the concepts underlying targeted thrombolytic therapy and describes recent drug developments in this field. | Junping Zhang Guoxing Ma Zhimin Lv Yu Zhou Chunguang Wen Yaqing Wu Ruian Xu | 2014 | Neural Regeneration Research2014,9,13: | 2 |