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| 1 | Spatio-temporal association analysis of county potential in the Pearl River Delta during 1990-2009显示文摘According to the highway data and some socioeconomic data of 1990, 1994, 2000, 2005 and 2009 of county units in the Pearl River Delta, this paper measured urban integrated power of different counties in different years by factor analysis, and estimated each county's potential in each year by means of expanded potential model. Based on that, the spatio-temporal association patterns and evolution of county potential were analyzed using spatio-temporal autocorrelation methods, and the validity of spatio-temporal association patterns was verified by comparing with spatial association patterns and cross-correlation function. The main results are shown as follows:(1) The global spatio-temporal association of county potential showed a positive effect during the study period. But this positive effect was not strong, and it had been slowly strengthened during 1994–2005 and decayed during 2005–2009. The local spatio-temporal association characteristics of most counties' potential kept relatively stable and focused on a positive autocorrelation, however, there were obvious transformations in some counties among four types of local spatio-temporal association(i.e., HH, LL, HL and LH).(2) The distribution difference and its change of local spatio-temporal association types of county potential were obvious. Spatio-temporal HH type units were located in the central zone and Shenzhen-Dongguan region of the eastern zone, but the central spatio-temporal HH area shrunk to the Guangzhou-Foshan core metropolitan region only after 2000; the spatio-temporal LL area in the western zone kept relatively stable with a surface-shaped continuous distribution pattern, new LL type units emerged in the south-central zone since 2005, the eastern LL area expanded during 1994–2000, but then gradually shrunk and scattered at the eastern edge in 2009; the spatio-temporal HL and LH areas varied significantly.(3) The local spatio-temporal association patterns of county potential among the three zones presented significant disparity, and obvious difference between the eastern and central zones tended to decrease, whereas that between the western zone and the central and eastern zones further expanded.(4) Spatio-temporal autocorrelation methods can efficiently mine the spatio-temporal association patterns of county potential, and can better reveal the complicated spatio-temporal interaction between counties than ESDA methods. | MEI Zhixiong XU Songjun OUYANG Jun | 2015 | Journal of Geographical Sciences2015，25，3： | 2 |
| 2 | Intense blue photo-luminescence of the Tm3+/Yb3+co-doped single-crystallinehexagonal phase NaYF4nanorods?显示文摘 | Zeng Songjun Ren Guozhong Xu Changfu | 2011 | J Alloy Compd2011，509，5： | 1 |
| 3 | Intense blue photoluminescence of the Tm 3+ /Yb 3+ co-doped single-crystalline hexagonal phase NaYF 4 nanorods显示文摘 | Songjun Zeng Guozhong Ren Changfu Xu | 2010 | Journal of Alloys and Compounds2010，，5： | 1 |
| 4 | Upconversion luminescence and magnetic properties of ligand-free monodisperse lanthanide doped BaGdF 5 nanocrystals显示文摘 | Changfu Xu Mo Ma Liwen Yang Songjun Zeng Qibin Yang | 2011 | Journal of Luminescence2011，，12： | 1 |
| 5 | Design of All-Fused-Ring Electron Acceptors with High Thermal,Chemical,and Photochemical Stability for Organic Photovoltaics显示文摘High-performance donor-acceptor electron acceptors containing 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile(INCN)-type terminals are labile toward photooxidation and basic conditions,and new molecular designs toward electron acceptors that can achieve both high power conversion efficiencies and high stability are urgently needed.By replacing the central benzene ring in the classical ladder-type n-type semiconductor,2,2′-(indeno[1,2-b]fluorene-6,12-diylidene)dimalononitrile,with the electron-rich 4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b′]dithiophene,we report herein the design of 2,2′-(7,7,15,15-tetrahexyl-7,15-dihydro-sindaceno[1,2-b:5,6-b′]diindeno[1,2-d]thiophene-2,10(2H)-diylidene)dimalononitrile(ITYM),a new type of all-fused-ring electron acceptor(AFRA).A threestep reaction including a key Pd-catalyzed double C-H activation/intramolecular cyclization is established for the efficient synthesis of such type of electron acceptors.ITYM is confirmed by singlecrystal X-ray analysis,which shows a planar nonacyclic structure with strongπ-πstacking.Compared with the classical carbon-bridged INCN-type acceptors,ITYM exhibits extraordinary stability with very promising performance.The AFRA concept opens a new avenue toward high-efficiency and-stability organic photovoltaics(OPVs). | Xiaozhang Zhu Songjun Liu Qihui Yue Wuyue Liu Shaoming Sun Shengjie Xu | 2021 | CCS Chemistry2021，3，6： | 1 |
| 6 | Pollution characteristics of peroxyacetyl nitrate in karst areas in Southwest China显示文摘桂林是世界著名的地处喀斯特地区的旅游胜地,其光化学污染问题日益严重,过氧乙酰硝酸酯(PAN)被认为是光化学污染的可靠指标,也是本研究的重点.本研究于2021年10月首次观测了桂林的PAN的浓度为0.087-2.559ppb,同时探讨了PAN典型高值过程的成因.此次污染主要来源于东北方向污染气团的水平和高空输送,同时,高温,强辐射和低湿度等气象条件也促进了本地PAN的形成.本研究同时估算了桂林市的O3背景浓度为20.347ppb.这项研究为城市的光化学污染控制工作提供了理论基础。 | Songjun Guo Xu Wei Hongjiao Li Wen Qin Yijun Mu Jiongli Huang Chuan Nong Junchao Yang Dabiao Zhang Hua Lin Jingying Mao Zhaoyu Mo | 2024 | Atmospheric and Oceanic Science Letters2024，17，2： | 0 |
| 7 | Schistosomiasis Surveillance--China,2015−2018显示文摘Background The prevalence of schistosomiasis in China is at the lowest level in history,and sentinel surveillance sites of schistosomiasis have fully covered all epidemic areas of China.This article has analyzed the surveillance data for the last four years and can help guide the next stage of surveillance work at the national level,including the scope of surveillance,surveillance content,and surveillance methods,etc.Methods Data from the National Schistosomiasis Surveillance System were collected.The infection rate of schistosomiasis among the human population,livestock,snails,and the change of the breeding area of snails in sentinel surveillance sites for four consecutive years were analyzed,and the trends in schistosomiasis prevalence in surveillance sites were determined.Results The prevalence of schistosomiasis in all sentinel surveillance sites of China showed downward trends from 2015 to 2018 with infection rates decreasing in this time period for local human population(0.05%to 0.00%),the floating population(0.020% to 0.003%),and cattle(0.037% to 0.000%).No infected snails were found during the period.From 2015 to 2018,the total area of newly found habitats of snails(Oncomelania hupensis,O.hupensis)were 34,730 m^(2),1,367,694 m^(2),18,944 m^(2),and 50,420 m^(2),and the total area of re-emergent habitats of snails(O.hupensis)were 822,194 m^(2),1,391,779 m^(2),1,516,292 m^(2),and 1,750,558 m^(2),respectively.Conclusions and Implications for Public Health Practice The prevalence of schistosomiasis in human and livestock is going down and is sustained at a very low level,but new and re-emerging habitats of O.hupensis are new challenges regardless of the achievement of schistosomiasis control.Therefore,two actions are necessary to effectively further reduce the transmission risk of schistosomiasis:1)taking effective measures to control the source of infection of schistosomiasis;and 2)reducing the breeding areas of O.hupensis. | Yinlong Li Hui Dang Lijuan Zhang Guangping Li Xiaowei Shan Min Yuan Songjun Ding Yun Feng Meifen Shen Jia Xu Yanjun Jin Haijuan Du Wencheng Lu Wenqian Tang Dianwei Jiang Yi Yuan Shan Lyu Shizhu Li Xiao-nong Zhou | 2020 | China CDC weekly2020，2，3： | 0 |
| 8 | Study on Disturbances and Its Effects on Nature Reserves显示文摘As a widespread natural phenomenon, disturbances are considered a discrete event occurring in a natural ecosystem within various spatial and temporal scales. The present paper discusses the types of disturbances and their influence on the ecologic system in nature reserves. It is shown that nature reserves are facing a great challenge dealing with these disturbances. A rational control for disturbances should be improved in order to promote the healthy development of nature reserves this could be done by enhancing the publicity and training of environment protection, coupling management with communities around and other nature reserves, effective management methods, rational planning, and supporting nature servers. | Zhang Linying Zhou Yongzhang Xu Songjun | 2006 | Chinese Journal of Population,Resources and Environment2006，4，3： | 0 |
| 9 | Biomimetic,fire-resistant,ultralight and porous carbon fiber sponges enabling safe and efficient remediation of crude oil spills in harsh environments显示文摘Advanced absorbents must meet the requirements of superior hydrophobic/oleophilic behavior,favorable adsorption efficiency,and high photothermal and Joule heating performance to handle frequent crude oil spills.However,current carbon-based absorbents suffer from poor fire resistance,thus severely limiting their application in harsh environments.Herein,inspired by a bird’s nest,a polymer“welding”strategy is proposed to design a versatile absorbent in which the polymer serves as a“binder”to interconnect discontinuous fibers together to form a 3D welded structure.The continuous conductive networks endow the absorbent with high photothermal and Joule heating effect,thus achieving all-weather adsorption,and improving the adsorption efficiency of crude oil via the self-heating function.Compared with other absorbents,the absorbent prepared via polymer welding technology exhibited preferable comprehensive performance,such as superhydrophobicity,high fire resistance,and high absorption efficiency.Specially,the noninflammable absorbent can restrain the combustion of crude oil,thereby reducing its combustion in case of fire.The versatile absorbent is expected to provide a promising solution for the safe and effi-cient cleanup of crude oil spills in harsh environments.Overall,the unique polymer welding strategy can be developed into a universal strategy for other material systems to expand their applications. | Yushan Li Songjun Yao Song Yan Mei Xu Long Zheng Fei Pan Yeqiang Tan Xianze Yin | 2023 | Journal of Materials Science & Technology2023，，27： | 0 |
| 10 | Room-Temperature Single-Molecule Conductance Switch via Confined Coordination-Induced Spin-State Manipulation显示文摘The emergence of molecular spintronics offers a unique chance for the design of molecular devices with different spin-states,and the control of spin-state becomes essential for molecular spin switches.However,the intrinsic spin switching from low-to high-spin state is a temperature-dependent process with a small energy barrier where low temperature is required to maintain the low-spin state.Thus,the room-temperature operation of single-molecule devices has not yet been achieved.Herein,we present a reversible single-molecule conductance switch by manipulating the spin states of the molecule at room temperature using the scanning tunneling microscope break-junction(STM-BJ)technique.The manipulation of the spin states between S=0 and S=1 is achieved by complexing or decomplexing the pyridine derivative molecule with a square planar nickel(Ⅱ)porphyrin.The bias-dependent conductance evolution proves that the strong electric field between the nanoelectrodes plays a crucial role in the coordination reaction.The density functional theory(DFT)calculations further reveal that the conductance changes come from the geometric changes of the porphyrin ring and spin-state switching of the Ni(Ⅱ)ion.Our work provides a new avenue to investigate room-temperature spin-related sensors and molecular spintronics. | Jing Li Qingqing Wu Wei Xu Hai-Chuan Wang Hewei Zhang Yaorong Chen Yongxiang Tang Songjun Hou Colin JLambert Wenjing Hong | 2022 | CCS Chemistry2022，4，4： | 0 |
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