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Journal of geographical sciences 2025年第1期 17-38页

作者： ZHU Wenbin LU Yu institute of Geographic sciences and Natural resources research CAS School of geographical Science Nanjing University of Information Science & Technology

The Qinba Mountains are climatically and ecologically recognized as the northsouth transitional zone of *** of its phenology is critical for comprehending the response of vegetation to climatic *** retrieved the start of spring phenology （SOS）of eight forest communities from the MODIS products and adopted it as an indicator for spring *** analysis,partial correlation analysis,and Geo Detector were employed to reveal the spatio-temporal patterns and climatic drivers of *** results indicated that the SOS presented an advance trend from 2001 to 2020,with a mean rate of–0.473 d yr–*** SOS of most forests correlated negatively with air temperature （TEMP） and positively with precipitation （PRE）,suggesting that rising TEMP and increasing PRE in spring would forward and delay SOS,*** dominant factors influencing the sensitivity of SOS to climatic variables were altitude,forest type,and latitude,while the effects of slope and aspect were relatively *** response of SOS to climatic factors varied significantly in space and among forest communities,partly due to the influence of altitude,slope,and aspect.

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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han Jia Tuo Liu Yuzhen Yang Jun Yang Key Laboratory of Noise and Vibration research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck institute for Gravitational Physics (Albert Einstein institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Impacts of LUCC processes on potential land productivity in China in the 1990s

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Science China Earth sciences 2005年第8期48卷 1259-1269页

作者： LIU Jiyuan XU Xinliang ZHUANG Dafang GAO Zhiqiang institute of geographical sciences and Natural resources research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Using meteorological data and RS dynamic land-use observation data set, the po-tential land productivity that is limited by solar radiation and temperature is estimated and the impacts of recent LUCC processes on it are analyzed in this paper. The results show that the influence of LUCC processes on potential land productivity change has extensive and unbal-anced characteristics. It generally reduces the productivity in South China and increases it in North China, and the overall effect is increasing the total productivity by 26.22 million tons. The farmland reclamation and original farmlands losses are the primary causes that led potential land productivity to change. The reclamation mostly distributed in arable-pasture and arable-forest transitional zones and oasises in northwestern China has made total productivity increase by 83.35 million tons, accounting for 3.50% of the overall output. The losses of original farmlands driven by built-up areas invading and occupying arable land are mostly distributed in the regions which have rapid economic development, e.g. Huang-Huai-Hai plain, Yangtze River delta, Zhu-jiang delta, central part of Gansu, southeast coastal region, southeast of Sichuan Basin and Urumqi-Shihezi. It has led the total productivity to decrease 57.13 million tons, which is 2.40% of the overall output.

关键词： land-use change, potential land productivity, photosynthetic productivity, photosynthetic thermal pro-ductivity, total photosynthetic thermal productivity.

A surface engineering strategy for the stabilization of zinc metal anodes with montmorillonite layers toward long-life rechargeable aqueous zinc ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 94-105页

作者： Wenbo Wang Ruifeng Xu Xu Zhang Peiyu Wang Bao Yang Bingjun Yang Juan Yang Kailimai Su Pengjun Ma Yanan Deng Xianfeng Fan Wanjun Chen Key Laboratory for Electronic Materials College of Electrical Engineering Northwest Minzu University Resource Chemistry and Energy Materials research Center State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences institute for Materials and Processes School of Engineering University of Edinburgh

Rechargeable aqueous zinc-ion batteries （AZIBs） exhibit appreciable potential in the domain of electrochemical energy ***,there are serious challenges for AZIBs,for instance zinc dendrite growth,hydrogen evolution reaction （HER）,and corrosion side ***,we propose a surface engineering modification strategy for coating the montmorillonite （MMT） layer onto the surface of the Zn anode to tackle these issues,thereby achieving high cycling stability for rechargeable *** results reveal that the MMT layer on the surface of the Zn anode is able to provide ordered zincophilic channels for zinc ions migration,facilitating the reaction kinetics of zinc *** functional theory（DFT） calculations and water contact angle （CA） tests prove that MMT@Zn anode exhibits superior adsorption capacity for Zn2+and better hydrophobicity than the bare Zn anode,thereby achieving excellent cycling ***,the MMT@Zn||MMT@Zn symmetric cell holds the stable cycling over 5600 h at 0.5 mA cm-2and 0.125 m A h cm-2,even exceeding 1800 h long cycling under harsh conditions of 5 m A cm-2and 1.25 m A h *** MMT@Zn||V2O5full cell reaches over 3000 cycles at 2 A g-1with excellent rate ***,this surface engineering modification strategy for enhancing the electrochemical performance of AZIBs represents a promising application.

关键词： Surface engineering strategy Montmorillonite layer Protection mechanism of Zn anode Cycling stability Aqueous zinc ion batteries

Environmental behaviors of selenium in soil of typical selenosis area,China

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Journal of Environmental sciences 2008年第7期20卷 859-864页

作者： LI Yonghua WANG Wuyi LUO Kunli institute of geographical sciences and Natural resources research Chinese Academy of SciencesBeijing 100101China

Daba Mountain area is one of the two endemic selenosis areas in China,which may relate with the environmental behaviors of selenium (Se) in *** study focuses on the concentraion and distribution of Se and its relationships with some other elements in natural soil in the *** average concentration of Se in Daba Mountain soils was 14.3 times higher than the value cited for natural soil background worldwide,suggesting that soils in the region were contaminated by the *** finding was confirmed...

关键词： selenium (Se) selenosis area geoaccumulation index soil profile

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of sciences School of Astronomy and Space sciences University of Chinese Academy of sciences Key Laboratory of Particle Astrophysics institute of High Energy Physics Chinese Academy of sciences institute of Space sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai institute of Technical Physics Chinese Academy of sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey institute for Cosmic Ray research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space sciences University of Science and Technology of China institute of Deep Space sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Sediment transferring function of the lower reaches of the Yellow River influenced by drainage basin factors and human activities

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Science China Earth sciences 2005年第12期48卷 2194-2202页

作者： XU Jiongxin institute of geographical sciences and Natural resources research ChineseAcademy of Sciences Beijing 100101 China

Sediment transferring function (Fs) of rivers is defined and indexed in this study, based on the concept of sediment budget at river reach scales. Then, study is made on the Fs of the lower reaches of the Yellow River in relation to natural and human factors in the drainage basin, such as the annual precipitation in different water and sediment source areas, proportion of >0.05 mm sediment of the total sediment load to the lower reaches of Yellow River, the regu-lated degree of the “clear” baseflow from the drainage area above Lanzhou, frequency of hy-perconcentrated flows, area of soil and water conservation measures in the drainage basin. As a result, a multiple regression equation has been established between Fs and 7 influencing factors, with multiple correlation coefficient r = 0.90. The reduction in annual precipitation in different water and sediment source areas has different effects on Fs. The reduction in annual precipitation in the area above Hekou Town and the area between Longmen and Sanmenxia results in a reduction in Fs, but the reduction in annual pre-cipitation in the area between Hekou Town and Longmen results in an increase in Fs. The grain size composition of sediment load strongly affects the Fs; the larger the proportion of >0.05 mm sediment in the suspended sediment load entering the lower reaches of the Yellow River is, the lower the Fs will be. Thus, if the Xiaolangdi Reservoir traps coarse sediment and releases fine sediment, Fs will be enhanced. This study also shows that the lower the proportion of high-flow season river flow to the annual total river flow at Lanzhou Station is, the lower the Fs will be. Therefore, the interception of large quantities of clear water by the reservoirs on the upper reaches of Yellow River is one of the major causes for the decrease in Fs in the lower reaches of the Yellow River.

关键词： river sediment, channel sedimentation, drainage basin factors, human activities, Yellow River.

Spatial Polarization of Villages in Tourist Destinations: A Case Study from Yesanpo, China

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Journal of Mountain Science 2015年第4期12卷 1038-1050页

作者： XI Jian-chao KONG Qin-qin WANG Xin-ge institute of geographical sciences and Natural resources research Chinese Academy of Sciences Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of sciences

Spatial perspectives were applied to examine the processes of growth and development in rural settlements affected by *** on field surveys and GIS spatial analysis methods, we studied the spatial evolution of two villages(Jiaojiekou and Gougezhuang) in the Yesanpo tourist area over the last 25 *** results revealed a polarization trend,with Jiaojiekou becoming a ‘hollowed' village and Gougezhuang developing into a ‘new-type' tourist *** polarization indicates the unsustainability of rural development in tourist destinations, which is manifested by the following features: only some villages benefit from the development of tourism;there is simultaneously a shortage of land in tourist villages and a wastage of land in traditional villages;and the function of the villages is ***, the spillover of the effects of tourism may provide an opportunity for the development of traditional *** better utilize this opportunity,we propose that:(1) integrated rural tourism management should be developed to explore effective methods of promoting tourism as part of a rural development strategy;(2) different land use policies are required for different villages; and(3) the balance between government regulation and community participation should be emphasized.

关键词： Spatial polarization Land use change Rural tourism Traditional villages Sustainable development