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46篇 您的检索式:作者名="Chengyi Liu"
    题名 作者 年代 出处 被引量
1Epidemic spreading behavior in local-world evolving networks显示文摘The susceptible-infected-susceptible(SIS)epidemic model is presented which can be used to study the epidemic spreading behavior in the local-world evolving network model.Local-world evolving model displays a transition from the exponential network to the scale-free network with respect to the connectivity distribution.From theoretical analyses and numerical simulations,we find that the epidemic spreading behavior on local-world networks also takes on some kind of transitional behaviors.The transitional behavior is further ver-ified by comparing the spreading behavior of local-world network with that of random and scale-free networks.Some feasible control strategies are also proposed to keep from the epidemic spreading on networks.Chengyi Xia Zhongxin Liu Zengqiang Chen Shiwen Sun Zhuzhi Yuan 2008Progress in Natural Science:Materials International2008,18,6:17
2Dynamic spreading behavior of homogeneous and heterogeneous networks显示文摘传播在上的 dynsmic 流行病的详细调查同类并且 heteiogeneous 网络被执行。在基本流行模型的分析以后,同质、异构的网络上的 susceptible-infected-susceptible (SIS ) 模型被建立,并且在网络的这二种不同类型的感染的个人的密度的动态进化理论上被分析。它显示对 piopagate 更容易的那异构的网络 sre 因为流行病和领先的传播行为被在起始的爆发的指数的增加支配。感染在同类的上比那在异构的网络上是快得多的大规模模拟显示。它意味着网络拓扑学能在发生在复杂网络上的流行病上有重要效果。根据理论分析和数字模拟介绍的流行爆发 sre 的某抑制 sfrategies。XIA Chengyi LIU Zhongxin CHEN Zengqiang YUAN Zhuzhi 2007Progress in Natural Science:Materials International2007,17,3:11
3Numerical simulations of land surface physical processes and land-atmosphere interactions over oasis-desert/Gobi region显示文摘A land-surface physical process model was coupled with a mesoscale atmospheric model. This cou- pled model was then used to simulate the interactions between land and the atmosphere, including surface temperature, net radiation, sensible heat flux and latent heat flux over a desert/Gobi with an oasis in northwestern semiarid regions in China. Comparisons between observations and simulations were made over the oasis and the desert/Gobi, respectively. Both cold island effect and wet island ef- fect, the so-called oasis effect, were observed and simulated. Lower temperature, higher specific hu- midity and weaker turbulent transfer were present over the oasis than the desert/Gobi. A subsidence occurred over the oasis, leading to a thermally-generated mesoscale circulation.LIU ShuHua LIU HePing HU Yu ZHANG ChengYi LIANG FuMing WANG JianHua 2007Science China Earth Sciences2007,50,2:9
4Effect of groundwater depth on riparian plant diversity along riverside-desert gradients in the Tarim River显示文摘Aims Riparian plant diversity is sensitive to changes in groundwater in arid regions.However,little is known about how plant diversity responds to changes in environment along riverside-desert gradi-ents in riparian ecosystem.Our objectives were to(i)identify ri-parian plant diversity along riverside-desert gradients in Tarim desert riparian forests,(ii)analyze the impact of environment variables on plant diversity,(iii)determine the optimum groundwater depth for different plant life-forms.Methods Six transects 90 quadrats(with each size 100 m×100 m)distributed vertically to river bed along riverside-desert gradients~30 km in length were surveyed.At each quadrat,the morphological features of riparian plant communities were measured,and the groundwater depth,soil water,soil salinity,soil nutrient were also monitored at same sites.Important Finding Three distinct vegetation communities were identified based on cover and richness in the tree,shrub and herb layers:the riparian zone,the transitional zone and the desert margin zone.Twelve spe-cies were indicators of the three vegetation communities.Riparian plant diversity was influenced by groundwater depth,distance from river,soil moisture content,soil salinity and soil nutrient by redundancy analysis.In response to groundwater depth,the op-timal groundwater depths for species diversity,evenness and shrub cover were 2.8,2.7 and 3.7 m,respectively.Therefore,maintaining high plant diversity requires managers to ensure stable groundwater depth for different plant life-forms rather than for some of them.Yong Zeng Chengyi Zhao Jun Li Yan Li Guanghui Lv Tong Liu 2019Journal of Plant Ecology2019,12,3:7
5Competition between Populus euphratica and Tamarix ramosissima seedlings under simulated high groundwater availability显示文摘Desert riparian plants experience high variability in water availability due to hydrological fluctuations. How riparian plants can survive with low water availability has been well studied, however, little is known about the effects of high water availability on plant community structuring. We conducted a mesocosm experiment to test whether seedling competition under simulated high groundwater availability can explain the shift of co-dominance of Populus euphratica and Tamarix ramosissima in early communities to P. euphratica dominance in mature ones along the Tarim River in northwestern China. Seedlings of these two plant species were grown in monoculture and mixture pools with high groundwater availability. Results indicated that the above-ground biomass and relative yield of T. ramosissima were higher than those of P. euphratica. The competitive advantages of T. ramosissima included its rapid response in growth to groundwater enrichment and its water spender strategy, as evidenced by the increased leaf biomass proportion and the inert stomatal response to leaf-to-air vapor pressure deficit(VPD). In comparison, P. euphratica showed a conservative strategy in water use, with a sensitive response to leaf-to-air VPD. Result of the short-term competition was inconsistent with the long-term competition in fields, suggesting that competition exclusion is not the mechanism structuring the desert riparian plant communities. Thus, our research highlights the importance of mediation by environmental fluctuations(such as lessening competition induced by disturbance) in structuring plant communities along the Tarim riparian zones.WU Guilin JIANG Shaowei LIU Weiyang ZHAO Chengyi LI Jun 2016Journal of Arid Land2016,8,2:4
6Ternary organic solar cells based on polymer donor,polymer acceptor and PCBM components显示文摘In this work,ternary organic solar cells(OSCs)combining a fullerene derivative PC71BM with a nonfullerene acceptor N2200-F blended with a polymer donor PM6 were reported.Compared with the binary systems,the highest power conversion efficiency(PCE)of 8.11%was achieved in ternary solar cells with 30 wt%N2200-F content,mainly due to the improved short-circuit current density(Jsc)and fill factor(FF).Further studies showed that the improved Jsc could attribute to the complementary abso rption of the two acceptors and the enhanced FF was originated from the higher hole mobility and the fine-tuned morphology in the ternary system.These results demonstrate that the combination of fullere ne and nonfullerene acceptors in ternary organic solar cells is a promising approach to achieve high-performance OSCs.Feng Liu Cheng Li Junyu Li Chao Wang Chengyi Xiao Yonggang Wu Weiwei Li 2020Chinese Chemical Letters2020,31,3:3
7Extraordinary characteristics for one-dimensional parity-time-symmetric periodic ring optical waveguide networks显示文摘In this paper, we design a one-dimensional(1D) parity-time-symmetric periodic ring optical waveguide network(PTSPROWN) and investigate its extraordinary optical characteristics. It is found that quite different from traditional vacuum/dielectric optical waveguide networks, 1D PTSPROWN cannot produce a photonic ordinary propagation mode, but can generate simultaneously two kinds of photonic nonpropagation modes: attenuation propagation mode and gain propagation mode. It creates neither passband nor stopband and possesses no photonic band structure. This makes 1D PTSPROWN possess richer spontaneous PT-symmetric breaking points and causes interesting extremum spontaneous PT-symmetric breaking points to appear, where electromagnetic waves can create ultrastrong extraordinary transmission, reflection, and localization, and the maximum can arrive at 6.6556 × 10^(12) and is more than 7 orders of magnitude larger than the results reported previously.1D PTSPROWN may possess potential in designing high-efficiency optical energy saver devices, optical amplifiers, optical switches with ultrahigh monochromaticity, and so on.YAN ZHI XIANGBO YANG JIAYE WU SHIPING DU PEICHAO CAO DONGMEI DENG CHENGYI TIMON LIU 2018Photonics Research2018,6,6:2
8MoS2/C/C nanofiber with double-layer carbon coating for high cycling stability and rate capability in lithium-ion batteries显示文摘MoS2 has attracted a lot of interest in the field of lithium-ion storage as ananode material owing to its high capacity and two-dimensional (2D)-layerstructure. However, its electrochemical properties, such as rate capability andcycling stability, are usually limited by its low conductivity, volume variation, andpolysulfide dissolution during lithiation/delithiation cycling. Here, a designedtwo-layer carbon-coated MoS2/carbon nanofiber (MoS2/C/C fiber) hybrid electrodewith a double-layer carbon coating was achieved by a facile hydrothermal andsubsequent electrospinning method. The double carbon layer (inner amorphouscarbon and outer carbon fiber) shells could efficiently increase the electronconductivity, prevent the aggregation of MoS2 flakes, and limit the volumechange and polysulfide loss during long-term cycling. The as-prepared MoS2/C/Cfiber electrode exhibited a high capacity of up to 1,275 mAh/g at a currentdensity of 0.2 A/g, 85.0% first cycle Coulombic efficiency, and significantlyincreased rate capability and cycling stability. These results demonstrate thepotential applications of MoS2/C/C fiber hybrid material for energy storage andmay open up a new avenue for improving electrode energy storage performanceby fabricating hybrid nanofiber electrode materials with double-layer carboncoatings.Hao Wu Chengyi Hou Guozhen Shen Tao Liu Yuanlong Shao Ru Xiao Hongzhi Wang 2018Nano Research2018,11,11:2
9Two Ultraviolet Radiation Datasets that Cover China显示文摘Ultraviolet(UV) radiation has significant effects on ecosystems, environments, and human health, as well as atmospheric processes and climate change. Two ultraviolet radiation datasets are described in this paper. One contains hourly observations of UV radiation measured at 40 Chinese Ecosystem Research Network stations from 2005 to 2015. CUV3 broadband radiometers were used to observe the UV radiation, with an accuracy of 5%, which meets the World Meteorology Organization's measurement standards. The extremum method was used to control the quality of the measured datasets. The other dataset contains daily cumulative UV radiation estimates that were calculated using an all-sky estimation model combined with a hybrid model. The reconstructed daily UV radiation data span from 1961 to 2014. The mean absolute bias error and root-mean-square error are smaller than 30% at most stations, and most of the mean bias error values are negative, which indicates underestimation of the UV radiation intensity. These datasets can improve our basic knowledge of the spatial and temporal variations in UV radiation. Additionally, these datasets can be used in studies of potential ozone formation and atmospheric oxidation, as well as simulations of ecological processes.Hui LIU Bo HU Yuesi WANG Guangren LIU Liqin TANG Dongsheng JI Yongfei BAI Weikai BAO Xin CHEN Yunming CHEN Weixin DING Xiaozeng HAN Fei HE Hui HUANG Zhenying HUANG Xinrong LI Yan LI Wenzhao LIU Luxiang LIN Zhu OUYANG Boqiang QIN Weijun SHEN Yanjun SHEN Hongxin SU Changchun SONG Bo SUN Song SUN Anzhi WANG Genxu WANG Huimin WANG Silong WANG Youshao WANG Wenxue WEI Ping XIE Zongqiang XIE Xiaoyuan YAN Fanjiang ZENG Fawei ZHANG Yangjian ZHANG Yiping ZHANG Chengyi ZHAO Wenzhi ZHAO Xueyong ZHAO Guoyi ZHOU Bo ZHU 2017Advances in Atmospheric Sciences2017,34,7:2
10Fuzzy controller design for synchronous motion in a dual-cylinder electro-hydraulic system显示文摘Chen Chengyi Liu Liqiang Cheng Chicheng 2008Control Engineering Practice2008,16,6:1
11Controlled direct synthesis of single- to multiple-layer MWW zeolite显示文摘The minimized diffusion limitation and completely exposed strong acid sites of the ultrathin zeolites make it an industrially important catalyst especially for converting bulky molecules.However,the structure-controlled and large-scale synthesis of the material is still a challenge.In this work,the direct synthesis of the single-layer MWW zeolite was demonstrated by using hexamethyleneimine and amphiphilic organosilane as structure-directing agents.Characterization results confirmed the formation of the single-layer MWW zeolite with high crystallinity and excellent thermal/hydrothermal stability.The formation mechanism was rigorously revealed as the balanced rates between the nucleation/growth of the MWW nanocrystals and the incorporation of the organosilane into the MWW unit cell,which is further supported by the formation of MWW nanosheets with tunable thickness via simply changing synthesis conditions.The commercially available reagents,well-controlled structure and the high catalytic stability for the alkylation of benzene with 1-dodecene make it an industrially important catalyst.Jie-Qiong Chen Yu-Zhao Li Qing-Qing Hao Huiyong Chen Zhao-Tie Liu Chengyi Dai Jianbo Zhang Xiaoxun Ma Zhong-Wen Liu 2021National Science Review2021,8,7:1
12Analysis of diffusion behavior of harmful emissions from trackless rubber-wheel diesel vehicles in underground coal mines显示文摘To define the diffusion behavior of harmful exhaust substances from diesel vehicles and support safety risk assessments of underground coal mines,we performed a multi-species coupling calculation of the emission and diffusion of harmful substances from a trackless rubber-wheel diesel vehicle.A computational fluid dynamics(CFD)model of the diffusion of harmful emissions was hence established and verified.From the perspective of risk analysis,the diffusion behavior and distribution of hazardous substances emitted by the diesel vehicle were studied under 4 different conditions;moreover,we identified areas characterized by hazardous levels of emissions.When the vehicle idled upwind in the roadway,high-risk areas formed behind and to the right of the vehicle:particularly high concentrations of pollutants were measured near the rear floor of the vehicle and within 5 m behind the vehicle.When the vehicle idled downwind,high-risk areas formed in front of it:particularly high concentrations of pollutants were measured near the floor and within 5 m from the front of the vehicle.In the above cases,the driver would not breathe highly polluted air and would be relatively safe.When the vehicle idled into the chamber,however,high-risk areas formed on both sides of the vehicle and near the upper roof.Forward entry of the vehicle caused a greater increase in the concentration of pollutants in the chamber and in the driver’s breathing zone compared with reverse entry.Yun Hua Wen Nie Qiang Liu Xiaofei Liu Chengyi Liu Weiwei Zhou Fengning Yu 2022International Journal of Mining Science and Technology2022,32,6:1
13GPER mediates enhanced cell viability and motility via non-genomic signaling induced by 17β-estradiol in triple-negative breast cancer cells显示文摘Tenghua Yu Manran Liu Haojun Luo Chengyi Wu Xi Tang Shifu Tang Ping Hu Yuzhao Yan Zhiliang Wang Gang Tu 2014Journal of Steroid Biochemistry and Molecular Biology2014,,:1
14Speckle Reduction Algorithm for Synthenic Aperture Radar Images Based on Bayesian Maximum a Posteriori Estimation in Wavelet Domain显示文摘Hou Jianhua Liu Xiangming Xiong Chengyi 2008Optical Engineering2008,47,5:1
15Efficient architectures for two-dimensional discrete wavelet transform using lifting scheme显示文摘Xiong Chengyi Tian Jinwen Liu Jian 2007IEEE Trans on Image Processing2007,16,3:1
16Speckle reduction algorithm for synthetic aperture radar images based on Bayesian maximum a posteriori estimation in wavelet domain 显示文摘Hou Jianhua Liu Xiangming Xiong Chengyi 2008Optical Engineering2008,47,5:1
17Efficient architectures for two-dimensional discrete wavelet transform using lifting scheme显示文摘Chengyi Xiong Jinwen Tian Jian Liu 2007IEEE Transactions on Image Processing2007,16,3:1
18Roles of autophagy?related genes Beclin?1 and LC3 in the developmentand progression of prostate cancer and benign prostatic hyperplasia显示文摘Chengyi Liu Pengcheng Xu Degang Chen Xinhuan Fan Yipeng Xu Mengqiang Li Xu Yang Congfei Wang 2013Biomedical Reports2013,,6:1
19High performance word level sequential and parallel coding methods and architectures for bit plane coding显示文摘This paper introduced a novel high performance algorithm and VLSI architectures for achieving bit plane coding (BPC) in word level sequential and parallel mode. The proposed BPC algorithm adopts the techniques of coding pass prediction and par- allel & pipeline to reduce the number of accessing memory and to increase the ability of concurrently processing of the system, where all the coefficient bits of a code block could be coded by only one scan. A new parallel bit plane architecture (PA) was proposed to achieve word-level sequential coding. Moreover, an efficient high-speed architecture (HA) was presented to achieve multi-word parallel coding. Compared to the state of the art, the proposed PA could reduce the hardware cost more efficiently, though the throughput retains one coefficient coded per clock. While the proposed HA could perform coding for 4 coefficients belonging to a stripe column at one intra-clock cycle, so that coding for an N×N code-block could be completed in approximate N2/4 intra-clock cycles. Theoretical analysis and ex- perimental results demonstrate that the proposed designs have high throughput rate with good performance in terms of speedup to cost, which can be good alternatives for low power applications.XIONG ChengYi TIAN JinWen LIU Jian 2008Science in China(Series F)2008,51,4:1
20In-situ monitoring of dynamic behavior of catalyst materials and reaction intermediates in semiconductor catalytic processes显示文摘Semiconductor photocatalysis, as a key part of solar energy utilization, has far-reaching implications for industrial, agricultural, and commercial development. Lack of understanding of the catalyst evolution and the reaction mechanism is a critical obstacle for designing efficient and stable photocatalysts. This review summarizes the recent progress of in-situ exploring the dynamic behavior of catalyst materials and reaction intermediates. Semiconductor photocatalytic processes and two major classes of in-situ techniques that include microscopic imaging and spectroscopic characterization are presented. Finally, problems and challenges in in-situ characterization are proposed, geared toward developing more advanced in-situ techniques and monitoring more accurate and realistic reaction processes, to guide designing advanced photocatalysts.Zhen Fang Yao Liu Chengyi Song Peng Tao Wen Shang Tao Deng Xiaoqin Zeng Jianbo Wu 2022Journal of Semiconductors2022,43,4:1
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