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32篇 您的检索式:作者名="Qin Lifeng"
    题名 作者 年代 出处 被引量
1Human umbilical cord mesenchymal stem cell-loaded amniotic membrane for the repair of radial nerve injury显示文摘In this study,we loaded human umbilical cord mesenchymal stem cells onto human amniotic membrane with epithelial cells to prepare nerve conduits,i.e.,a relatively closed nerve regeneration chamber.After neurolysis,the injured radial nerve was enwrapped with the prepared nerve conduit,which was fixed to the epineurium by sutures,with the cell on the inner surface of the conduit.Simultaneously,a 1.0 mL aliquot of human umbilical cord mesenchymal stem cell suspension was injected into the distal and proximal ends of the injured radial nerve with 1.0 cm intervals.A total of1.75×107cells were seeded on the amniotic membrane.In the control group,patients received only neurolysis.At 12 weeks after cell transplantation,more than 80%of patients exhibited obvious improvements in muscular strength,and touch and pain sensations.In contrast,these improvements were observed only in 55–65%of control patients.At 8 and 12 weeks,muscular electrophysiological function in the region dominated by the injured radial nerve was significantly better in the transplantation group than the control group.After cell transplantation,no immunological rejections were observed.These findings suggest that human umbilical cord mesenchymal stem cell-loaded amniotic membrane can be used for the repair of radial nerve injury.Zhi Li Hanjiao Qin Zishan Feng Wei Liu Ye Zhou Lifeng Yang Wei Zhao Youjun Li 2013Neural Regeneration Research2013,8,36:13
2Effect of extrusion speed on microstructure and mechanical properties of the Mg-Ca binary alloy显示文摘This work reported the effect of extrusion speeds on the microstructures and mechanical properties of Mg-Ca binary alloy.The results showed that yield strength of the as-extruded Mg-1.2wt.%Ca alloys decrease from∼360MPa to∼258MPa as the ram speed increases from 0.4mm/s to 2.4 mm/s,and the elongation increases from∼3.9%to∼12.2%.The microstructure changes from bimodal grain feature to the complete dynamical recrystallization(DRX)with increase of the extrusion speed.The ultrafine DRXed grains in size of∼0.85μm,the numerous nano-Mg_(2)Ca particles dispersing along the grain boundaries and interiors,as well as the high density of residual dislocations,should account for the high strength.It is believed that the high degree of dynamic recrystallization and the resulting texture randomization play the critical roles in the ductility enhancement of the high-speed extruded Mg alloys.Jingren Li Aiyue Zhang Hucheng Pan Yuping Ren Zhuoran Zeng Qiuyan Huang Changlin Yang Lifeng Ma Gaowu Qin 2021Journal of Magnesium and Alloys2021,9,4:9
3Heterogeneous lamellar-edged Fe-Ni(OH)_(2)/Ni_(3)S_(2)nanoarray for efficient and stable seawater oxidation显示文摘Development of efficient non-precious catalysts for seawater electrolysis is of great significance but challenging due to the sluggish kinetics of oxygen evolution reaction(OER)and the impairment of chlorine electrochemistry at anode.Herein,we report a heterostructure of Ni_(3)S_(2)nanoarray with secondary Fe-Ni(OH)_(2)lamellar edges that exposes abundant active sites towards seawater oxidation.The resultant Fe-Ni(OH)_(2)/Ni_(3)S_(2)nanoarray works directly as a free-standing anodic electrode in alkaline artificial seawater.It only requires an overpotential of 269 mV to afford a current density of 10 mA·cm^(-2)and the Tafel slope is as low as 46 m V·dec^(-1).The 27-hour chronopotentiometry operated at high current density of 100 mA·cm^(-2)shows negligible deterioration,suggesting good stability of the Fe-Ni(OH)_(2)/Ni_(3)S_(2)@NF electrode.Faraday efficiency for oxygen evolution is up to〜95%,revealing decent selectivity of the catalyst in saline water.Such desirable catalytic performance could be benefitted from the introduction of Fe activator and the heterostructure that offers massive active and selective sites.The density functional theory(DFT)calculations indicate that the OER has lower theoretical overpotential than Cl_(2) evolution reaction in Fe sites,which is contrary to that of Ni sites.The experimental and theoretical study provides a strong support for the rational design of high-performance Fe-based electrodes for industrial seawater electrolysis.Baihua Cui Zheng Hu Chang Liu Siliang Liu Fangshuai Chen Shi Hu Jinfeng Zhang Wei Zhou Yida Deng Zhenbo Qin Zhong Wu Yanan Chen Lifeng Cui Wenbin Hu 2021Nano Research2021,14,4:7
4Laser direct writing and characterizations of flexible piezoresistive sensors with microstructures显示文摘Functional materials with high viscosity and solid materials have received more and more attentions in flexible pressure sensors,which are inadequate in the most used molding method.Herein,laser direct writing(LDW)method is proposed to fabricate flexible piezoresistive sensors with microstructures on PDMS/MWCNTs composites with an 8%MWCNTs mass fraction.By controlling laser energy,microstructures with different geometries can be obtained,which significantly impacts the performances of the sensors.Subsequently,curved microcones with excellent performance are fabricated under parameters of f=40 kHz and v=150 mm·s^(-1).The sensor exhibits continuous multi-linear sensitivity,ultrahigh original sensitivity of 21.80%kPa^(-1),wide detection range of over 20 kPa,response/recovery time of~100 ms and good cycle stability for more than 1000 times.Besides,obvious resistance variation can be observed when tiny pressure(a peanut of 30 Pa)is applied.Finally,the flexible piezoresistive sensor can be applied for LED brightness controlling,pulse detection and voice recognition.Chenying Zhang Wei Zhou Da Geng Cheng Bai Weida Li Songyue Chen Tao Luo Lifeng Qin Yu Xie 2021Opto-Electronic Advances2021,4,4:7
5Microstructural and mechanical response of ZK60 magnesium alloy subjected to radial forging显示文摘Radial forging(RF)is an economical manufacturing forging process,in which four dies arranged radially around the workpiece simultaneously act on the workpiece with high-frequency radial movement.In this study,a ZK60 magnesium alloy step-shaft bar was processed under different accumulated strains by RF at350℃.The deformation behavior,microstructure evolution,and mechanical responses of this bar were systematically investigated via numerical simulations and experiments.At the early deformation stage of forging,the material undergoes pronounced grain refinement but an inhomogeneous grain structure is formed due to the strain gradient along the radial direction.The grains in different radial parts were gradually refined by increasing the RF pass,resulting in a bimodal grained structure comprising coarse(~14.1μm)and fine(~2.3μm)grains.With the RF pass increased,the initial micro-sizeβ-phases were gradually crushed and dissolved into the matrix mostly,eventually evolving to form a higher area fraction of nano-sized Zn2 Zr spheroidal particles uniformly distributed through the grain interior.The texture changed as the RF strain increased,with the c-axes of most of the deformed grains rotating in the RD.Additionally,excellent mechanical properties including higher values of tensile strengths and ductility were attained after the three RFed passes,compared to the as-received sample.Jingfeng Zou Lifeng Ma Weitao Jia Qichi Le Gaowu Qin Yuan Yuan 2021Journal of Materials Science & Technology2021,,24:4
6The Construction of Active Source Repeated Monitoring in the Qilian Mountain, Gansu Province显示文摘The exciting source of the active source repeated monitoring is located in the Xiliushui Reservoir in Zhangye,Gansu Province. The system began operating normally on July 9,2015,and we had completed a period of 40 days of continuous excitation experiment before November 10,2015. Our results reveal that the airgun source has good consistency and repeatability,and the detective system of active source can record signal clearly. The construction of active source repeated exploration projects has achieved some results,which can provide valuable experience for the research of active source repeated exploration. The observation data we obtained makes it possible to follow the temporal and spatial variations of the deep structure of the Qilian Mountain areas.Zhang Yuansheng Guo Xiao Qin Manzhong Liu Xuzhou Wei Congxin Shen Xuzhang Yan Wenhua Zou Rui Yin Liang Wang Yahong Sun Dianfeng Feng Hongwu Zhang Lifeng Guo Yingxia 2016Earthquake Research in China2016,30,3:4
7Rapid on-line non-destructive detection of the moisture content of corn ear by bioelectrical impedance spectroscopy显示文摘Moisture content of corn directly affects its quality and storage time,and the rapid on-line detection of the moisture content of corn ears not threshed or in vivo in the fields is required.Because of the special shape of corn ear,the rapid,low cost and non-destructive bioelectrical impedance measurement is more suitable for its moisture content detection.Using the four-electrode method with the Agilent E4980A precision LCR meter,the electrical impedance spectroscopies of the sweet corn ears and waxy corn ears at different moisture contents were acquired.The frequency range of the detection was from 20 Hz to 2 MHz and to enhance the contact,the attached-type electrodes were wrapped in cotton soaked with 0.1%NaCl solution.The impedance data over the frequency range from 300 Hz to 5 kHz were used to obtain the parameters of the bio-impedance Cole-Cole model.The results showed a good linear correlation(coefficient of determination R2=0.960)between the equivalent parallel resistance R∞of sweet corn ear and the moisture content value determined by standard chemical method.The research proved that the bioelectrical impedance spectroscopy can be used for detecting the moisture content of corn ear.Zhao Pengfei Zhang Hanlin Zhao Dongjie Wang Zhijie Fan Lifeng Huang Lan Ma Qin Wang Zhongyi 2015International Journal of Agricultural and Biological Engineering2015,8,6:3
8The electromechanical features of LiNbO_(3) crystal for potential high temperature piezoelectric applications显示文摘Lithium niobate(LiNbO_(3),LN)crystal is a multi-functional material with favorable piezoelectric,nonlinear optical and electro-optic properties.In this study,the electromechanical properties of the radial extensional(RE)and the thickness extensional(TE)modes of the congruent LN are studied and the temperature dependent behaviors are revealed.The RE mode electromechanical coupling factors(kp)for the Y-and Z-oriented discs are calculated and found to be 3.8%and 24.7%,respectively,which are nearly the same as the experimental results of 3.8%and 25.2%,respectively.The maximum RE and thickness shear(TS)modes electromechanical coupling factors are obtained to be 47.6%and 68.5%for the Yx/25and Yx/167crystal cuts,respectively.The LN crystal possesses good temperature stability of the electromechanical coupling factors(RE and TE modes)from 20℃ to 500℃,where the variations of kp and kt for the Y-oriented discs are<8.0%and<1.8%,respectively.Feifei Chen Lingfeng Kong Wei Song Chao Jiang Shiwei Tian Fapeng Yu Lifeng Qin Xian Zhao 2019Journal of Materiomics2019,5,1:3
9Quasi-Lipschitz equivalence of quasi Ahlfors-David regular sets显示文摘Suppose compact sets E and F are quasi uniformly disconnected and quasi Ahlfors-David regular.This paper proves that E and F are quasi-Lipschitz equivalent if and only if they have the same Hausdorff dimension.WANG Qin XI LiFeng 2011Science China Mathematics2011,54,12:3
10Integration of QTL detection and marker assisted selection for improving resistance to Fusarium head blight and important agronomic traits in wheat显示文摘Fusarium head blight(FHB), caused by Fusarium graminearum, is one of the most destructive wheat(Triticum aestivum L.) diseases worldwide. Identification of quantitative trait loci(QTL) conferring FHB resistance followed by marker assisted selection(MAS) is an efficient approach to breed FHB-resistant varieties. In this study, 38 additive QTL and 18 pairs of epistatic QTL for FHB resistance were detected in four environments using a population of recombinant inbred lines(RILs) derived from varieties Neixiang 188 and Yanzhan 1. Six QTL clusters were located on chromosomes 2D, 4B, 4D, 5A, 5D and 7B, suggesting possible polytrophic functions. Six elite lines with good FHB resistance and agronomic traits were selected from the same population using the associated markers. Our results suggest that MAS of multiple QTL will be effective and efficient in wheat breeding.Chao Lv Yanxia Song Lifeng Gao Qin Yao Ronghua Zhou Rugen Xu Jizeng Jia 2014The Crop Journal2014,2,1:2
11The development of taste transduction and taste chip technology显示文摘The intrinsic perception process of taste is ob- viously far less known than those of vision, audition, touch and olfaction. Despite that taste cells utilize a variety of sen- sory mechanisms to translate plenty of gustatory sensations such as sour, sweet, bitter, salty and umami into cellular sig- nals, gustatory perception mechanisms are still under explo- ration due to the lack of effective methods on cellular and molecular level. Recently the development of molecular bio- logical and electrophysiological studies has promoted explo- ration of olfactory and gustatory transduction and coding mechanisms dramatically. Based on the studies of artificial olfaction, artificial taste and cell-based biosensor in our laboratory, this paper reviews the current research on taste transduction mechanism. We introduce the recent advances in cell chip that combined biology with microelectronics, discuss taste cell chip as well as its potential of prospective application in taste transduction mechanism in detail and propose the research trends of taste chip in future.LI Yan LIU Qingjun XU Ying CAI Hua QIN Lifeng WANG Lijiang WANG Ping 2005Chinese Science Bulletin2005,50,14:2
12Mass sensitivity of thin film bulk acoustic resonator sensors based on po- lar c-axis tilted zinc oxide and aluminum nitride thin film显示文摘QIN Lifeng WANG Qingming 2010J Appl Phys2010,108,10:1
13Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells显示文摘Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.Yijun Yao Zhifang Li Bowen Qin Xingrong Ju Lifeng Wang 2024Food Science and Human Wellness2024,13,1:1
14Synthesis of thermostable geopolymer from circulating fluidized bed combustion (CFBC) bottom ashes显示文摘Xu Hui Li Qin Shen Lifeng 2010J Hazard Mater2010,175,123:1
15N-9 Alkylation of purines via light-promoted and metal-free radical relay显示文摘A metal-free and light-promoted approach to the synthesis of N-9 alkylated purine nucleoside derivatives, via a CF3 radical triggered radical relay pathway, has been developed. Purine nucleoside derivatives were prepared regioselectively in good to high yields. Photosensitizers and metals are free in this transformation. Visible light or even sunlight can be used as the source of light for the reactions.Runze Mao Lifeng Sun Yong-Shi Wang Min-Min Zhou De-Cai Xiong Qin Li Xin-Shan Ye 2018Chinese Chemical Letters2018,29,1:1
16Low-rcactive circulating fluidized bed combustion( CFBC ) fly ashes as source material for geopolymer synthesis 显示文摘Hui Xu Qin Li Lifeng Shen etc 2010Waste Management2010,,30:1
17Synthesis of thermostable geopoly- mer from circulating fiuidized bed combustion ( CFBC ) bottom ashes 显示文摘Hui Xu Qin Li Lifeng Shen etc 2010Journal of Hazardous Materials2010,,175:1
18Simulation Study on Virtual Prototype of Pumping Well System 显示文摘HukunYang Guichuan Zhan Jingyuan Yang Lifeng Qin 2013Advanced Materials Research2013,,1:1
19Cell-based biosensors and its application in biomedicine显示文摘Wang Ping Xu Gaixia Qin Lifeng 2005Sensors Actuators B2005,108,:1
20A straw-soil co-composting and evaluation for plant substrate in BLSS显示文摘Quanyong Cheng Shuangsheng Guo Weidang Ai Yongkang Tang Lifeng Qin 2012Advances in Space Research2012,,:1
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