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| 1 | Spatial dynamics of aboveground carbon stock in urban green space:a case study of Xi'an,China显示文摘Greenhouse gas emission of carbon dioxide(CO2) is one of the major factors causing global climate change.Urban green space plays a key role in regulating the global carbon cycle and reducing atmospheric CO2.Quantifying the carbon stock,distribution and change of urban green space is vital to understanding the role of urban green space in the urban environment.Remote sensing is a valuable and effective tool for monitoring and estimating aboveground carbon(AGC) stock in large areas.In the present study,different remotely-sensed vegetation indices(VIs) were used to develop a regression equation between VI and AGC stock of urban green space,and the best fit model was then used to estimate the AGC stock of urban green space within the beltways of Xi'an city for the years 2004 and 2010.A map of changes in the spatial distribution patterns of AGC stock was plotted and the possible causes of these changes were analyzed.Results showed that Normalized Difference Vegetation Index(NDVI) correlated moderately well with AGC stock in urban green space.The Difference Vegetation Index(DVI),Ratio Vegetation Index(RVI),Soil Adjusted Vegetation Index(SAVI),Modified Soil Adjusted Vegetation Index(MSAVI) and Renormalized Difference Vegetative Index(RDVI) were lower correlation coefficients than NDVI.The AGC stock in the urban green space of Xi'an in 2004 and 2010 was 73,843 and 126,621 t,respectively,with an average annual growth of 8,796 t and an average annual growth rate of 11.9%.The carbon densities in 2004 and 2010 were 1.62 and 2.77 t/hm2,respectively.Precipitation was not an important factor to influence the changes of AGC stock in the urban green space of Xi'an.Policy orientation,major ecological greening projects such as 'transplanting big trees into the city' and the World Horticultural Exposition were found to have an important impact on changes in the spatiotemporal patterns of AGC stock. | ZhengYang YAO JianJun LIU XiaoWen ZHAO DongFeng LONG Li WANG | 2015 | Journal of Arid Land2015，7，3： | 13 |
| 2 | Porous nitrogen-doped carbon/MnO coaxial nanotubes as an efficient sulfur host for lithium sulfur batteries显示文摘As a promising candidate for next generation energy storage devices, lithium sulfur (Li-S) batteries still confrant rapid capacity degradation and low rate capability. Herein, we report a well-architected porous nitrogen-doped carbon/MnO coaxial nanotubes (MnO@PNC) as an efficient sulfur host material. The host shows excellent electron conductivity, sufficient ion transport channels and strong adsorption capability for the polysulfides, resulting from the abundant nitrogen-doped sites and pores as well as MnO in the carbon shell of MnO@PNC. The MnO@PNC-S composite electrode with a sulfur content of 75 wt.% deliveries a specific capacity of 802 mAh·g^-1 at a high rate of 5.0C and outstanding cycling stability with a capacity retention of 82% after 520 cycles at 1.0C. | Chao Lin Longbing Qu Jiantao Li Zhengyang Cai Haoyun Liu Pan He Xu Xu Liqiang Mai | 2019 | Nano Research2019，12，1： | 10 |
| 3 | Controlled release and biocompatibility of polymer/titania nanotube array system on titanium implants显示文摘Bacterial infection and tissue inflammation are the major causes of early failure of titanium-based orthopedic implants;thus,surgical implants with tunable drug releasing properties represent an appealing way to address some of these problems of bacterial infection and tissue inflammation in early age of orthopedic implants.In this work,a hybrid surface system composed of biodegradable poly(lactic-coglycolic acid)(PLGA)and titania nanotubes(TNTs)has been successfully constructed on Ti implants with the aim of preventing bacterial infection via long-term drug release.By varying the size of the TNTs and the thickness of the polymer film,the drug release profile can be tuned to achieve the optimal therapeutic action throughout the treatment time.The size of TNTs plays a dominant role in the drug loading dose of TNTs/PLGA hybrid coatings.In this work,TNTs with an average size of 80 nm can achieve the largest loading dose.Depending on the polymer thickness,significant improvement in the drug release characteristics is attained,for instance,reduced burst release(from 84%to 27%)and overall release time extended from 5 to over 40 days.In addition,the PLGA layers may favor the proliferation and osteogenesis of MC3T3-E1 mouse cells at an earlier stage.Therefore,this TNT/PLGA hybrid surface system can be employed as an effective bioplatform for improving both self-antibacterial performance and biocompatibility of Ti-based biomaterials. | Tingting Wang Zhengyang Weng Xiangmei Liu Kelvin W.K.Yeung Haobo Pan Shuilin Wu | 2017 | Bioactive Materials2017，2，1： | 8 |
| 4 | Confined van der Waals Epitaxial Growth of Two-Dimensional Large Single-Crystal In_(2)Se_(3) for Flexible Broadband Photodetectors显示文摘The controllable growth of two-dimensional(2D)semiconductors with large domain sizes and high quality is much needed in order to reduce the detrimental efect of grain boundaries on device performance but has proven to be challenging.Here,we analyze the precursor concentration on the substrate surface which signifcantly infuences nucleation density in a vapor deposition growth process and design a confned micro-reactor to grow 2D In_(2)Se_(3) with large domain sizes and high quality.Te uniqueness of this confned micro-reactor is that its size is∼102-103 times smaller than that of a conventional reactor.Such a remarkably small reactor causes a very low precursor concentration on the substrate surface,which reduces nucleation density and leads to the growth of 2D In_(2)Se_(3) grains with sizes larger than 200�m.Our experimental results show large domain sizes of the 2D In_(2)Se_(3) with high crystallinity.Te fexible broadband photodetectors based on the as-grown In_(2)Se_(3) show rise and decay times of 140 ms and 25 ms,efcient response(5.6 A/W),excellent detectivity(7×10^(10) Jones),high external quantum efciency(251%),good fexibility,and high stability.Tis study,in principle,provides an efective strategy for the controllable growth of high quality 2D materials with few grain boundaries. | Lei Tang Changjiu Teng Yuting Luo Usman Khan Haiyang Pan Zhengyang Cai Yue Zhao Bilu Liu Hui-Ming Cheng | 2019 | Research2019，，1： | 7 |
| 5 | Optical observations of LIGO source GW 170817 by the Antarctic Survey Telescopes at Dome A,Antarctica显示文摘The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light. | lei hu xuefeng wu igor andreoni michael c.b.ashley jeff cooke xiangqun cui fujia du zigao dai bozhong gu yi hu haiping lu xiaoyan li zhengyang li ensi liang liangduan liu bin ma zhaohui shang tianrui sun n.b.suntzeff charling tao syed a.uddin lifan wang xiaofeng wang haikun wen di xiao jin xu ji yang shihai yang xiangyan yuan hongyan zhou hui zhang jilin zhou zonghong zhu | 2017 | Science Bulletin2017，62，21： | 6 |
| 6 | Electrochemical machining of burn-resistant Ti40 alloy显示文摘This study investigates the feasibility of using electrochemical machining(ECM) to produce critical aeroengine components from a new burn-resistant titanium alloy(Ti40), thereby reducing costs and improving efficiency relative to conventional mechanical machining.Through this, it is found that an aqueous mix of sodium chloride and potassium bromide provides the optimal electrolyte and that the surface quality of the Ti40 workpiece is improved by using a pulsed current of1 k Hz rather than a direct current.Furthermore, the quality of cavities produced by ECM and the overall material removal rate are determined to be dependent on a combination of operating voltage, electrolyte inlet pressure, cathode feeding rate and electrolyte concentration.By optimizing these parameters, a surface roughness of 0.371 lm has been achieved in conjunction with a specific removal rate of more than 3.1 mm3/A?min. | Xu Zhengyang Liu Jia Zhu Dong Qu Ningsong Wu Xiaolong Chen Xuezhen | 2015 | Chinese Journal of Aeronautics2015，28，4： | 6 |
| 7 | Cathode design investigation based on iterative correction of predicted profile errors in electrochemical machining of compressor blades显示文摘Electrochemical machining(ECM) is an effective and economical manufacturing method for machining hard-to-cut metal materials that are often used in the aerospace field. Cathode design is very complicated in ECM and is a core problem influencing machining accuracy, especially for complex profiles such as compressor blades in aero engines. A new cathode design method based on iterative correction of predicted profile errors in blade ECM is proposed in this paper. A mathematical model is first built according to the ECM shaping law, and a simulation is then carried out using ANSYS software. A dynamic forming process is obtained and machining gap distributions at different stages are analyzed. Additionally, the simulation deviation between the prediction profile and model is improved by the new method through correcting the initial cathode profile. Furthermore, validation experiments are conducted using cathodes designed before and after the simulation correction. Machining accuracy for the optimal cathode is improved markedly compared with that for the initial cathode. The experimental results illustrate the suitability of the new method and that it can also be applied to other complex engine components such as diffusers. | Zhu Dong Liu Cheng Xu Zhengyang Liu Jia | 2016 | Chinese Journal of Aeronautics2016，29，4： | 5 |
| 8 | Dissolution Characteristics of New Titanium Alloys in Electrochemical Machining显示文摘We focus on the electrochemical dissolution characteristics of new titanium alloys such as near-αtitanium alloy Ti60,α+βtitanium alloy TC4andβtitanium alloy Ti40 which are often used for aerospace industry.The experiments are carried out by electrochemical machining tool,and the surface morphology of the specimens is observed by the scanning electron microscope(SEM)and three-dimensional video microscope(DVM).The appropriate electrolyte is selected and the relationships between surface roughness and current density are achieved.The results show that the single-phase titanium alloy Ti40 has a better surface roughness after ECM compared with theα+βtitanium alloy TC4 and the near-αtitanium alloy Ti60.The best surface roughness is Ra 0.28μm when the current density is 75A/cm2.Furthermore,the surface roughness of the near-αtitanium alloy Ti60 is the most sensitive with the current density because of the different electrochemical equivalents of substitutional elements and larger grains than TC4.Finally,the suitable current density for each titanium alloy is achieved. | Chen Xuezhen Zhu Dong Xu Zhengyang Liu Jia Zhu Di | 2016 | Transactions of Nanjing University of Aeronautics and Astronautics2016，33，5： | 3 |
| 9 | A high quality image reconstruction method based on nonconvex decoding显示文摘The article proposes a fast reconstruction algorithm for l0≤p≤1 norm nonconvex model,called Gradient projection nonconvex sparse recovery(GPNSR),which makes a good performance in high-quality image reconstruction.We apply the GPNSR into canonical multiple description coding theory and propose a robust high-quality compressed sensing-based coding method.Combined with iterative weighted technique and fast gradient descent method,the proposed method implicitly implements matrix inverse operations to highly reduce the storage pressure.Also the weighted norm method is taken to optimize the descent steps,which highly increases convergent speed of the algorithm.Taking an image has sparse Fourier representations as an example,the paper presents the detailed image sparse coding and fast reconstruction procedure.By integrating the compressive sensing multi-description coding framework,the simulation demonstrates the superior reconstruction performance of the proposed algorithm.Most importantly,with p close to zero,the reconstruction performance of GPNSR can approximate that of l0 norm optimization result. | ZHAO GuangHui SHEN FangFang WANG ZhengYang WU WeiJia SHI GuangMing LIU DanHua | 2013 | Science China(Information Sciences)2013，56，11： | 3 |
| 10 | Spatially defined single-cell transcriptional profiling characterizes diverse chondrocyte subtypes and nucleus pulposus progenitors in human intervertebral discs显示文摘A comprehensive understanding of the cellular heterogeneity and molecular mechanisms underlying the development,homeostasis,and disease of human intervertebral disks(IVDs)remains challenging.Here,the transcriptomic landscape of 108108 IVD cells was mapped using single-cell RNA sequencing of three main compartments from young and adult healthy IVDs,including the nucleus pulposus(NP),annulus fibrosus,and cartilage endplate(CEP).The chondrocyte subclusters were classified based on their potential regulatory,homeostatic,and effector functions in extracellular matrix(ECM)homeostasis.Notably,in the NP,a PROCR+resident progenitor population showed enriched colony-forming unit-fibroblast(CFU-F)activity and trilineage differentiation capacity.Finally,intercellular crosstalk based on signaling network analysis uncovered that the PDGF and TGF-βcascades are important cues in the NP microenvironment.In conclusion,a single-cell transcriptomic atlas that resolves spatially regulated cellular heterogeneity together with the critical signaling that underlies homeostasis will help to establish new therapeutic strategies for IVD degeneration in the clinic. | Yibo Gan Jian He Jun Zhu Zhengyang Xu Zhong Wang Jing Yan Ou Hu Zhijie Bai Lin Chen Yangli Xie Min Jin Shuo Huang Bing Liu Peng Liu | 2021 | Bone Research2021，9，3： | 3 |
| 11 | Molecular cloning and expression patterns of the cholesterol side chain cleavage enzyme(CYP11A1) gene during the reproductive cycle in goose(Anas cygnoides)显示文摘Background: CYP11A1, a gene belonging to the family 11 of cytochrome P450, encodes a crucial steroidogenic enzyme that catalyzes the initial step in the production of all classes of steroids. Many studies show that CYP11A1 plays a role in ovary function. However, the role of CYP11A1 in goose reproductive cycle remains largely unknown.Results: In this study, full-length CYP11A1 c DNA of Zhedong goose was obtained using reverse transcription polymerase chain reaction(RT-PCR) and rapid amplification of c DNA ends(RACE). The c DNA consisted of a 96-base pair(bp) 5′untranslated region(UTR), a 179-bp 3′UTR and a 1509-bp open reading frame. The open reading frame encodes a putative 503 amino acid protein that shares high homology with CYP11A1 of other birds. The amino acid sequence possesses conserved domains of the P450 superfamily, which include the steroid-binding domain and the heme-binding region. Real-time quantitative polymerase chain reaction(q PCR) analysis revealed CYP11A1 mR NA was expressed ubiquitously in every Zhedong goose tissue analyzed, including the heart, liver, glandular stomach,lung, spleen, kidney, intestinum tenue, intestinum crassum, cerebrum, cerebellum, muscle, oviduct, pituitary,hypothalamus and ovary.. The relatively low levels of CYP11A1 m RNA were detected in pituitary, ovary and oviduct tissues at ovulation when compared with levels at oviposition. Interestingly, higher expression was observed in ovary and oviduct tissues during brooding. Lastly, higher m RNA expression of Yangzhou geese was detected during the ovulation period than that of Zhedong geese.Conclusions: Our findings reveal the sequence characterization and expression patterns of the CYP11A1 gene during the goose reproductive cycle, which may provides correlative evidence that CYP11A1 expression is important in reproduction activity. | Qi Xu Yadong Song Yang Chen Ran Liu Yang Zhang Yang Li Zhengyang Huang Wenming Zhao Guobin Chang Guohong Chen | 2016 | Journal of Animal Science and Biotechnology2016，7，2： | 2 |
| 12 | Dissolution-precipitation growth of uniform and clean two dimensional transition metal dichalcogenides显示文摘Two dimensional transition metal dichalcogenides(TMDCs)have attracted much interest and shown promise in many applications.However,it is challenging to obtain uniform TMDCs with clean surfaces,because of the difficulties in controlling the way the reactants are supplied to the reaction in the current chemical vapor deposition growth process.Here,we report a new growth approach called’dissolution-precipitation’(DP)growth,where the metal sources are sealed inside glass substrates to control their feeding to the reaction.Noteworthy,the diffusion of metal source inside glass to its surface provides a uniform metal source on the glass surface,and restricts the TMDC growth to only a surface reaction while eliminating unwanted gas-phase reaction.This feature gives rise to highly uniform monolayer TMDCs with a clean surface on centimeter-scale substrates.The DP growth works well for a large variety of TMDCs and their alloys,providing a solid foundation for the controlled growth of clean TMDCs by the fine control of the metal source. | Zhengyang Cai Yongjue Lai Shilong Zhao Rongjie Zhang Junyang Tan Simin Feng Jingyun Zou Lei Tang Junhao Lin Bilu Liu Hui-Ming Cheng | 2021 | National Science Review2021，8，3： | 2 |
| 13 | Assessment of strong earthquake risk in the Chinese mainland from 2021 to 2030显示文摘The long-term earthquake prediction from 2021 to 2030 is carried out by researching the active tectonic block boundary zones in the Chinese mainland.Based on the strong earthquake recurrence model,the cumulative probability of each target fault in the next 10 years is given by the recurrence period and elapsed time of each fault,which are adopted from relevant studies such as seismological geology,geodesy,and historical earthquake records.Based on the long-term predictions of large earthquakes throughout the world,this paper proposes a comprehensive judgment scheme based on the fault segments with the seismic gap,motion strongly locked,sparse small-moderate earthquakes,and apparent Coulomb stress increase.This paper presents a comprehensive analysis of the relative risk for strong earthquakes that may occur in the coming 10 years on the major faults in the active tectonic block boundary zones in the Chinese mainland.The present loading rate of each fault is first constrained by geodetic observations;the cumulative displacement of each fault is then estimated by the elapsed time since the most recent strong earthquake. | Zhigang Shao Yanqiang Wu Lingyun Ji Faqi Diao Fuqiang Shi Yujiang Li Feng Long Hui Zhang Wuxing Wang Wenxin Wei Peng Wang Xiaoxia Liu Qi Liu Zhengyang Pan Xiaofei Yin Yue Liu Wei Feng Zhenyu Zou Jia Cheng Renqi Lu Yueren Xu Xi Li | 2023 | Earthquake Research Advances2023，3，1： | 2 |
| 14 | Investigation on crater morphology by high repetitive rate YAG laser-induced discharge texturing显示文摘 | Zhengyang Li Yang Mingjiang Wenjin Liu Minlin Zhong | 2005 | Surface & Coatings Technology2005，，14： | 1 |
| 15 | XiaoMu: an AI-driven assistant for MOOCs显示文摘Nowadays, massive open online courses(MOOCs), are attracting widespread interest as an alternative education model. Several MOOCs platforms, such as Coursera, edX,and Udacity have been built and they provide low-cost opportunities for anyone who needs to access a massive number of courses from the worldwide top universities. However, the learning completion rate of the learners via MOOCs is extremely low compared with that in real classroom learning.Thus, this study builds a system, called XiaoMu, to design intelligent intervention strategies for the learning process of learners and improve the learning efficiency through automatic analysis of courses and learners. We deployed our system on the website1), which is one of the largest MOOCs in China. | Zhengyang SONG Jie TANG Tracy Xiao LIU Wenjiang ZHENG Lili WU Wenzheng FENG Jing ZHANG | 2021 | Science China(Information Sciences)2021，64，6： | 1 |
| 16 | Added Value of Diffusion-weighted MR Imaging to T2-weighted and Dynamic Contrast-enhanced MR Imaging in T Staging of Gastric Cancer显示文摘 | Song Liu Jian He Wenxian Guan Qiang Li Haiping Yu Zhuping Zhou Shanhua Bao Zhengyang Zhou | 2013 | Clinical Imaging2013，，： | 1 |
| 17 | High-frequency enhanced response based on Sb_(2)Te_(3)topological insulators显示文摘Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase transitions. However, the effects of high-frequency driving topological intrinsic systems have remained largely unexplored challenges experimentally for high-sensitivity terahertz detection. In this study, by integrating Sb2Te3 topological insulators with subwavelength metal antennas through micro-nano processing, a high-frequency terahertz detector with high sensitivity is proposed. The enhanced response originates from the asymmetric scattering of the surface electrons in the Sb_(2)Te_(3) flakes induced by the terahertz wave. The device displays room-temperature photodetection with a responsivity of 192 mA/W and equivalent noise power of less than 0.35 nW/Hz^(1/2) in the frequency range from 0.02 to 0.3 THz. These results pave the way for the exploitation of topological insulators for high-frequency operation in real-time imaging within long-wavelength optoelectronics. | SHI ZHANG CHAOFAN SHI WEIWEI TANG LIBO ZHANG LI HAN CHENGSEN YANG ZHENGYANG ZHANG JIAN WANG MIAO CAI GUANHAI LI CHANGLONG LIU LIN WANG XIAOSHUANG CHEN WEI LU | 2022 | Photonics Research2022，10，10： | 1 |
| 18 | Dynamic Contrast-Enhanced CT Characterization of Xp11.2 Translocation/TFE3 Gene Fusions versus Papillary Renal Cell Carcinomas显示文摘 | Jian He Kefeng Zhou Bin Zhu Gutian Zhang Xiaogong Li Hongqian Guo Weidong Gan Zhengyang Zhou Tian Liu Yi-Xiang Wang | 2015 | BioMed Research International2015，，： | 1 |
| 19 | Investigation on the flow field of W-shape electrolyte flow mode in electrochemical machining显示文摘 | Dong Zhu Di Zhu Zhengyang Xu Qing Xu Jia Liu | 2010 | Journal of Applied Electrochemistry2010，，3： | 1 |
| 20 | A study on hyperspectral estimating models of tobacco leaf area index显示文摘 | Zhang ZhengYang Ma XinMing Liu Guoshun | 2011 | African Journal of Agricultural Research2011，6，2： | 1 |
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