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18篇 您的检索式:作者名="Xia Qingfeng"
    题名 作者 年代 出处 被引量
1Passive-source ocean bottom seismograph(OBS) array experiment in South China Sea and data quality analyses显示文摘Long-term passive source ocean bottom seismograph(OBS) observatory is challenging due to various technical difficulties. In order to gain experience in this field, and to reveal the lithospheric structure beneath the extinct ridge in the central South China Sea(SCS), we carried out a passive source OBS array experiment, which includes 18 OBSs, in the deep portion of SCS. Here we present the instrumentation, the OBS deployment and recovery of this experiment, and more importantly, the data quality evaluated by a number of approaches. Through processing and inspecting waveforms from global, regional and local earthquakes, we find that most of recovered OBSs have good data quality with discernible main phases. The ambient noise analyses of OBS recordings show that their noise is higher than the global average, and the horizontal component is noisier than the vertical, indicating current impacts on horizontal components are more severe. In the period range of 5–10 s, there is a noise notch for the SCS OBSs, and noise levels of horizontal components are comparable to the vertical. This feature, which is not seen at OBS stations in open ocean, suggests the distant sources for double frequency microseism in this marginal sea are not significant. In addition, we successfully determined the orientations for 7 OBSs by investigating their Rayleigh wave polarizations; and we demonstrated the dispersion feature of Rayleigh waves through the frequency-time analysis. Finally, we summarized lessons learned from this experiment regarding the passive source OBS investigations in SCS.Chenguang Liu Qingfeng Hua Yanliang Pei Ting Yang Shaohong Xia Mei Xue Ba Manh Le Da Huo Fang Liu Haibo Huang 2014Chinese Science Bulletin2014,59,33:11
2Superior performance and high service stability for Ge Te-based thermoelectric compounds显示文摘GeTe-based compounds have been intensively studied recently due to their superior thermoelectric performance,but their real applications are still limited so far due to the drastic volume variation that occurs during the rhombohedral–cubic phase transition,which may break the material or the material/electrode interface during service.Here,superior performance and high service stability for GeTe-based thermoelectric compounds are achieved by co-doping Mg and Sb into GeTe.The linear coefficient of thermal expansion before phase transition is greatly improved to match that after phase transition,yielding smooth volume variation around the phase transition temperature.Likewise,co-doping(Mg,Sb)in GeTe successfully tunes the carrier concentration to the optimal range and effectively suppresses the lattice thermal conductivity.A peak z T of 1.84 at 800 K and an average z T of 1.2 in 300–800 K have been achieved in Ge0.85Mg0.05Sb0.1Te.Finally,a Ni/Ti/Ge0.85Mg0.05Sb0.1Te thermoelectric uni-leg is fabricated and tested,showing quite good service stability even after 450 thermal cycles between 473 K and 800 K.This study will accelerate the application of GeTe-based compounds for power generation in the mid-temperature range.Tong Xing Qingfeng Song Pengfei Qiu Qihao Zhang Xugui Xia Jincheng Liao Ruiheng Liu Hui Huang Jiong Yang Shengqiang Bai Dudi Ren Xun Shi Lidong Chen 2019National Science Review2019,6,5:4
3Systems model-guided rice yield improvements based on genes controlling source, sink, and flow显示文摘A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This perspective paper aims to examine the reasons behind such a phenomenon and propose a strategy to resolve this situation. Specifically, we first systematically survey the currently cloned genes related to source, sink, and flow;then we discuss three factors hindering effective application of these identified genes, which include the lack of effective methods to identify limiting or critical steps in a signaling network, the misplacement of emphasis on properties, at the leaf, instead of the whole canopy level,and the non-linear complex interaction between source,sink, and flow. Finally, we propose the development of systems models of source, sink and flow, together with a detailed simulation of interactions between them and their surrounding environments, to guide effective use of the identified elements in modern rice breeding. These systems models will contribute directly to the definition of crop ideotype and also identification of critical features and parameters that limit the yield potential in current cultivars.Pan Li Tiangen Chang Shuoqi Chang Xiang Ouyang Mingnan Qu Qingfeng Song Langtao Xiao Shitou Xia Qiyun Deng Xin-Guang Zhu 2018Journal of Integrative Plant Biology2018,60,12:4
4Study of brain morphology change in Alzheimer’s disease and amnestic mild cognitive impairment compared with normal controls显示文摘Background With an aggravated social ageing level, the number of patients with Alzheimer's disease (AD) is gradually increasing, and mild cognitive impairment (MCI) is considered to be an early form of Alzheimer's disease. How to distinguish diseases in the early stage for the purposes of early diagnosis and treatment is an important topic. Aims The purpose of our study was to investigate the differences in brain cortical thickness and surface area among elderly patients with AD, elderly patients with amnestic MCI (aMCI) and normal controls (NC). Methods 20 AD patients, 21 aMCIs and 25 NC were recruited in the study. FreeSurfer software was used to calculate cortical thickness and surface area among groups. Results The patients with AD had less cortical thickness both in the left and right hemisphere in 17 of the 36 brain regions examined than the patients with aMCI or NC. The patients with AD also had smaller cerebral surface area both in the left and right hemisphere in 3 of the 36 brain regions examined than the patients with aMCI or NC. Compared with the NC, the patients with aMCI only had slight atrophy in the inferior parietal lobe of the left hemisphere, and no significant difference was found. Conclusion AD, as well as aMCI (to a lesser extent), is associated with reduced cortical thickness and surface area in a few brain regions associated with cognitive impairment. These results suggest that cortical thickness and surface area could be used for early detection of AD.Huanqing Yang Hua Xu Qingfeng Li Yan Jin Weixiong Jiang Jinghua Wang Yina Wu Wei Li Cece Yang Xia Li Shifu Xiao Feng Shi Tao Wang 2019General Psychiatry2019,32,2:3
5Biomass Homogeneity Reinforced Carbon Aerogels Derived Functional Phase-Change Materials for Solar–Thermal Energy Conversion and Storage显示文摘We deviseda functional form stable compositephase-change materials(PCMs)toachieve a three-dimensional(3D)interconnectedporous carbon aerogel structure for encapsulating polyethyleneglycol(PEG).Anovelhomogeneity reinforced carbonaerogel witha well-interconnected porous structure was constructed bycombining a flexible carbonresource from biomass guar gum with hard-brittle carbonfrom polyimide,to overcome severeshrinkage andpoor mechanical performance of traditionalcarbon aerogel.Thesupportingcarbon aerogel-encapsulated PEG produced thenovel composite PCMswithgood structure stability andcomprehensive energy storage performance.Theresults showed thatthecomposite PCMsdisplayed awell-defined 3Dinterconnected structure,and theirenergy storage capacities were 171.5 and169.5 J/g,which changed onlyslightlyafter 100 thermalcycles,andthe compositescould maintainthe equilibrium temperature at50.0−58.1℃ for about 760.3 s.The thermal conductivityofthe compositescould reach0.62 W m^(−1) K^(−1),which effectively enhanced the thermalresponse rate.And thecomposite PCMs exhibited good leakage-proof performance andexcellent light–thermal conversion.The compressive strengthof thecomposite PCMscan improveupto 1.602 MPa.Results indicatethatthisstrategy canbe efficiently usedtodevelop novel composite PCMswithimproved comprehensive thermalperformance and high light–thermal conversion.Qingfeng Zhang Tingfeng Xia Qihan Zhang Yucao Zhu Huanzhi Zhang Fen Xu Lixian Sun Xiaodong Wang Yongpeng Xia Xiangcheng Lin Hongliang Peng Pengru Huang Yongjin Zou Hailiang Chu Bin Li 2023Energy & Environmental Materials2023,6,1:1
6Synthesis and optical properties of poly[(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] with 1,8-naphthalimide end group显示文摘A series of homopolymers,poly[(4-(benzoxazole-2-yl)phenyl)methyl methacrylate] (NAPH-PMABEs) containing benzoxazole side chain and 1,8-naphthalimide end group,were prepared by atom transfer radical polymerization (ATRP) and end-group modification. The structure of NAPH-PMABE was char-acterized by GPC,1H-NMR and UV-vis spectra. The polymer has good solubility in common organic solvents,such as dichloromethane (CH2Cl2),tetrahydrofuran (THF),N,N-dimethylformamide (DMF),chloroform (CHCl3),acetone and toluene. The optical properties of NAPH-PMABE were investigated. Results show that NAPH-PMABE has a composite emission spectrum comprising an ultraviolet com-ponent originating from benzoxazole side chains and a green component originating from 1,8-naphthalimide end group in both solution and film. The intensity of the two emission bands can be easily tuned by changing molecular weight.JIN ZhengNeng XU QingFeng LU JianMei YAN Feng XIA XueWei WANG LiHua LI NaJun 2009Chinese Science Bulletin2009,54,1:1
7Condition analysis of the steady gas-gas interface existence and the separation of gas and solid in supersonic gas phase flows 显示文摘Zhang Lite Gao Tieyu Xia Qingfeng 2006World Journal of Engineering2006,3,2:1
8The essential role of the death domain kinase receptor-interacting protein in growth factor-Ⅰ-induced c-Jun N-terminal kinase activation显示文摘Yong Lin Qingfeng Yang Xia Wang 2006J Biol Chem2006,281,23:1
9Variation in Sunshine Duration and Related Aerosol Influences at Shangdianzi GAW Station, China: 1958–2021显示文摘Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.Weijun QUAN Zhiqiang MA Ziming LI Xiaolan LI Yingruo LI Xiangao XIA Huaigang ZHOU Hujia ZHAO Zhenfa WANG Weiwei PU Fan DONG Di HE Liyan ZHOU Qingfeng SHI Wenyan WANG Fang JIA 2023Journal of Meteorological Research2023,37,4:0
10Ice-volume and insolation influences on hydroclimate changes in central eastern China during the antepenultimate glacial period显示文摘The rainfall changes in East Asian summer monsoon(EASM)regions on the orbital timescale remain controversial due to the lack of reliable rainfall records.Here,we present new multiproxy records(δ^(18)O,δ^(13)C,Sr/Ca and Mg/Ca)of a230Thdated stalagmite from Hulu Cave in central eastern China.Multiproxy records reconstruct a regional hydroclimate history from 340 to 261 kyr BP(thousand years before present),approximately covering the antepenultimate glacial period.Theδ^(18)O record is dominated by the precessional cycles,suggesting that EASM responds to changes in Northern Hemisphere summer insolation(NHSI)on the orbital timescale.Significant correlations amongst theδ^(13)C,Sr/Ca and Mg/Ca suggest that a common factor,i.e.,the local hydrological cycle,controlled their variability,and their leading principal component can be used as a proxy linked to regional rainfall.This composite record bears a good similarity to those from the Chinese Loess Plateau,showing a gradually decreasing rainfall during the antepenultimate glacial period,consistent with changes in global ice volume.Superimposed on the long-term trend,three relative wetter intervals were responding to the higher NHSI periods,suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and NHSI.The increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies,which shortened the duration of Meiyu and midsummer rainfall.The differences between the rainfall record and the stalagmiteδ^(18)O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation,but does not directly reflect the rainfall changes at the cave sites.Quan WANG Shayue YUAN Yijia LIANG Kan ZHAO Qingfeng SHAO Zhenqiu ZHANG Junji ZHU Xinggong KONG Yongjin WANG Jianghu LAN Hai CHENG Chengwei XIA Yi LI 2023Science China Earth Sciences2023,66,1:0
11Dissection of cellular and molecular mechanisms of aristolochic acid-induced hepatotoxicity via single-cell transcriptomics显示文摘Background:Aristolochic acids(AAs),a class of carcinogenic and mutagenic natural products from Aristolochia and Asarum plants,are well-known to be responsible for inducing nephrotoxicity and urothelial carcinoma.Recently,accumulating evidence suggests that exposure to AAs could also induce hepatotoxicity and even hepatocellular carcinoma,though the mechanisms are poorly defined.Methods:Here,we aimed to dissect the underlying cellular and molecular mechanisms of aristolochic acid I(AAI)-induced hepatotoxicity by using advanced single-cell RNA sequencing(scRNA-seq)and proteomics techniques.We established the first single-cell atlas of mouse livers in response to AAI.Results:In hepatocytes,our results indicated that AAI activated NF-κB and STAT3 signaling pathways,which may contribute to the inflammatory response and apoptosis.In liver sinusoidal endothelial cells(LSECs),AAI activated multiple oxidative stress and inflammatory associated signaling pathways and induced apoptosis.Importantly,AAI induced infiltration of cytotoxic T cells and activation of proinflammatory macrophage and neutrophil cells in the liver to produce inflammatory cytokines to aggravate inflammation.Conclusions:Collectively,our study provides novel knowledge of AAs-induced molecular characteristics of hepatotoxicity at a singlecell level and suggests future treatment options for AAs associated hepatotoxicity.Piao Luo Jiayun Chen Qian Zhang Fei Xia Chen Wang Yunmeng Bai Huan Tang Dandan Liu Liwei Gu Qingfeng Du Wei Xiao Chuanbin Yang Jigang Wang 2022Precision Clinical Medicine2022,5,4:0
12Modification Mechanism and Uniaxial Fatigue Performances of A356.2 Alloy Treated by Al-Sr-La Composite Refinement-Modification Agent显示文摘Modification mechanism and uniaxial fatigue properties of A356.2 alloy treated by Al-6Sr-7La and traditional Al-5Ti-1B/Al-10Sr(hereinafter refers to traditional treated alloy) were investigated by constant stress amplitude method. Microstructure, dislocation and Si twinning of the alloys were studied by thermal analysis, scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results showed that Al-6Sr-7La possesses better refining and modification effect than Al-5Ti-1B/Al-10Sr. Meanwhile, fatigue properties of the alloy treated by Al-6Sr-7La are higher than traditional treated alloy, and this is mainly owing to that Al-6Sr-7La treated alloy has more twins in eutectic Si and lower twin spacing. In addition, higher density of nanophases formed on twin faces and La-rich clusters appear at multiple twin intersections. Stacking faults and entrapped nanophases appeared on growing Si twin faces. Impurity induced twinning(IIT) mechanism and twin plane re-entrant edge(TPRE) mechanism are valid for eutectic Si which are important for mechanical optimization of A356.2 alloy.Liang Chang Qingfeng Zhao Xingchuan Xia Yuming Ding Binxu Guo Jian Ding Ying Tang Zan Zhang Chong Li Xiaomian Sun Junjie Guo Kaihong Song Yongchang Liu 2022Acta Metallurgica Sinica(English Letters)2022,35,6:0
13The density-and isospin-dependent■-formation cross section and its decay width显示文摘The energy-, density-, and isospin-dependent ?-formation cross section σ_(Nπ→?)~* and ?-decay width are calculated based on the relativistic BUU approach in which the effective mass splitting of nucleon and ? baryons in isospin-asymmetric matter is considered by the inclusion of the δ meson exchange in the effective Lagrangian density and the density-dependent coupling constants of Hofmann et al. The results show that the σ_(Nπ→?)~* is decreased(increased) moderately with increasing density with(without)the consideration of medium modifications on pion mass. Meanwhile, if the invariant mass of the system is not far from the ?pole mass, the ?-decay width is also weakly dependent on density. The mass splitting effect of differently charged nucleon and ?baryons on σ_(Nπ→?)~* is found to be more obvious than that of pion mesons but much weaker than the mass splitting in the hard ?production channel NN → N?. Further, the largest mass-splitting influence is seen in the π^-p → ?~0 and π^+n → ?^+ channels but not in the production of ?^- and ?^(++) isobars.QingFeng Li Zhu Xia Li 2019Science China(Physics,Mechanics & Astronomy)2019,62,7:0
14Negative effect on molecular planarity to achieve organic ternary memory: triphenylamine as the spacer显示文摘Adjusting the spacers between the electron-acceptor and the elector-donor is important to design organic ternary memory material but rarely reported. In this paper, two small molecules, ZIPGA and ZIPCAD with benzene ring or triphenylamine as the spacers,were designed and synthesized to fabricate memory devices. The Al/ZIPGA/indium-tin oxide (ITO) device showed ternary characteristics, whereas Al/ZIPCAD/ITO had no obvious memory characteristics. Density functional theory calculation, X-ray diffraction (XRD) and atomic force microscopy (AFM) were employed to interpret the different memory properties. ZIPGA thin film has the closer intermolecular packing and flatter surface morphology than ZIPCAD film, which was favorable to the electron migration. This work demonstrates the importance of spacers and reveals that triphenylamine may be not a good spacer in design of new memory material.Shugang Xia Jinghui He Hua Li Qingfeng Xu Najun Li Dongyun Chen Jianmei Lu 2016Science China Chemistry2016,59,6:0
15Tectonic implications of the subduction of the Kyushu-Palau Ridge beneath the Kyushu,southwest Japan显示文摘The Kyushu-Palau Ridge(KPR),a remnant arc on the Philippine Sea Plate(PSP),is subducting beneath the Kyushu,southwest Japan.Influenced by the subducting KPR,the Kyushu subduction zone corresponding to the KPR is significantly different from Shikoku subduction zone in terms of gravity anomalies,seismicity,the stress state,and the subducting slab morphology.Significant negative free-air and Bouguer gravity anomalies are observed in a prolonged area of KPR,southeast of the Miyazaki Plain,indicating that this is where KPR overlaps the overriding plate.The gravity anomaly in this area is much lower than that in other areas where the inferred KPR extends,suggesting that the subduction of the buoyant KPR may cause the lower mantle density to decrease.More earthquakes have occurred in Hyuga-nada region where the KPR subducts than in Shikoku forearc and other areas in the Kyushu forearc,indicating that the subduction of the KPR enhances the local coupling between the subducting and overriding plates.The centroid moment tensor(CMT)mechanism of earthquakes shows that stress is concentrated in the accumulated crust beneath the Kyushu forearc corresponding to the KPR,and the shallow thrusting events in the obducting plate are caused by the KPR subduction.The buoyant KPR,with a large volume of low-density sediments,was responsible for the differences of the subduction depth and dip angle of the subducting Philippine Sea(PS)slab between northern Kyushu and Shikoku.The seismic gaps and the sudden change of the dipping angle of the subducting PS slab indicate that slab tear may have occurred along the west side of the KPR beneath southwest Kyushu.A two-tear model was proposed,and the subduction of the buoyant KPR was believed to play an important role in the slab tear.Chenglong Xia Yanpeng Zheng Baohua Liu Qingfeng Hua Long Ma Xianfeng Li Qiuhong Xie 2021Acta Oceanologica Sinica2021,40,3:0
16Real-time performance analysis of non-saturated and non-slotted Ethernet based on a two-dimensional collision state model显示文摘Ronggang BAI Jiqiang XIA Qingfeng MAN 2015Frontiers of Computer Science2015,9,5:0
17High-temperature oxidation mechanism of ZrCoSb-based half-Heusler thermoelectric compounds显示文摘ZrCoSb-based half-Heusler(HH)compounds are among the most promising thermoelectric(TE)materials for high-temperature power generation.Oxidation resistance is one of the key issues for realizing the practical application of TE materials for long-term service in the ambient working environment.In this work,the oxidation behavior of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)(ZHCSS)half-Heusler is systematically studied in the service temperature range from 873 to 1073 K.It is revealed that three typical layers of oxidation products tend to form on the surface of HH sample,namely,the dense oxide layer(DOL)composed of(Zr,Hf)O_(2) and CoSb,the alternate oxide layer(AOL)composed of repeated(Zr,Hf)O_(2) and CoSb_(2)O_(6)/Co_(3)O_(4),and the CoSb layer between the DOL and AOL.The mass gain during oxidation is mainly caused by the rapid growth of AOL,which is controlled by the outward diffusion of Zr/Hf and the inward diffusion of oxygen.The formation of a continuous CoSb layer and DOL is found beneficial to block the outward diffusion of Zr/Hf.Based on the analysis of the dominant factors on the outward and inward diffusions as well as the reaction activation energy,a simple approach is proposed to improve the oxidation resistance of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)by pre-oxidizing the sample in low oxygen pressure to form the dense(Zr,Hf)O_(2) and CoSb layers as oxidation protecting and/or diffusion blocking layers.The oxidation test shows the effectiveness of such pre-oxidation on the formation and growth of the AOL and therefore on improving the service stability of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)at high temperatures in the air.Jinyu Gu Lei Wang Qingfeng Song Chao Wang Xugui Xia Jincheng Liao Yi-Yang Sun Lidong Chen Shengqiang Bai 2023Journal of Materials Science & Technology2023,,17:0
18Exposure to jet lag aggravates depression-like behaviors and age-related phenotypes in rats subject to chronic corticosterone显示文摘Our previous finding demonstrated that chronic corticosterone(CORT)may be involved in mediating the pathophysiology of premature aging in rats.Frequent jet lag increases the risk for many diseases,including obesity and type 2 diabetes,and is associated with the aging processes.However,the effect of jet lag on CORT-induced depression and its association with aging phenotypes remain unclear.In this study,the rats were exposed to both CORT and jet lag treatment,and the differences were analyzed and compared to rats with single CORT treatment.Our results showed that jet lag treatment aggravated CORT-induced depression-like behavior evidenced by sucrose intake test,forced swimming test,and open field test.Additionally,this treatment aggravated the shortening of telomeres,which possibly resulted in decreased telomerase activity,and downregulated the expression of telomere-binding factor 2(TRF2)and telomerase reverse transcriptase compared to that in CORT rats,as revealed by quantitative real-time-polymerase chain reaction and western blot analysis,respectively.The shortening of telomeres may have been caused by increased oxidative stress,which was associated with the inhibition of sirtuin 3.Exposure to jet lag also aggravated the degeneration of mitochondrial functions,as shown by the decreases in the mRNA expression of COX1,ND1,and Tfam.Our findings provide physiological evidence that jet lag exposure may worsen stress-induced depression and age-related abnormalities.Qichen Shen Junli Wu Yuehan Ni Xiaoxian Xie Chunan Yu Qingfeng Xiao Jiafeng Zhou Xia Wang Zhengwei Fu 2019Acta Biochimica et Biophysica Sinica2019,51,8:0
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