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Prediction of soil organic carbon stock combining Sentinel-1 and Sentinel-2 images in the Zoige Plateau, the northeastern Qinghai-Tibet Plateau

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Ecological Processes 2024年第2期13卷 165-176页

作者： Junjie Lei Changli Zeng Lv Zhang Xiaogang Wang Chanhua Ma tao Zhou Benjamin Laffitte Ke luo Zhihan Yang Xiaolu Tang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Sichuan Academy of Geological Survey Sichuan Institute of Nuclear Geological Survey College of Earth Sciences Chengdu University of Technology Tianfu Yongxing Laboratory

Background Soil organic carbon（SOC） is a critical component of the global carbon cycle, and an accurate estimate of regional SOC stock（SOCS） would significantly improve our understanding of SOC sequestration and cycles. Zoige Plateau, locating in the northeastern Qinghai-Tibet Plateau, has the largest alpine marsh wetland worldwide and exhibits a high sensitivity to climate fluctuations. Despite an increasing use of optical remote sensing in predicting regional SOCS, optical remote sensing has obvious limitations in the Zoige Plateau due to highly cloudy weather, and knowledge of on the spatial patterns of SOCS is limited. Therefore, in the current study, the spatial distributions of SOCS within 100 cm were predicted using an XGBoost model—a machine learning approach, by integrating Sentinel-1, Sentinel-2 and field observations in the Zoige *** The results showed that SOC content exhibited vertical distribution patterns within 100 cm, with the highest SOC content in topsoil. The tenfold cross-validation approach showed that XGBoost model satisfactorily predicted the spatial patterns of SOCS with a model efficiency of 0.59 and a root mean standard error of 95.2 Mg ha-1. Predicted SOCS showed a distinct spatial heterogeneity in the Zoige Plateau, with an average of 355.7 ± 123.1 Mg ha-1within 100 cm and totaled 0.27 × 10～9 Mg *** High SOC content in topsoil highlights the high risks of significant carbon loss from topsoil due to human activities in the Zoige Plateau. Combining Sentinel-1 and Sentinel-2 satisfactorily predicted SOCS using the XGBoost model, which demonstrates the importance of selecting modeling approaches and satellite images to improve efficiency in predicting SOCS distribution at a fine spatial resolution of 10 m. Furthermore, the study emphasizes the potential of radar（Sentinel-1） in developing SOCS mapping, with the newly developed fine-resolution mapping having important applications in land management, ecological resto

关键词： SOC Vegetation index Texture XGBoost Sentinel-1 Sentinel-2

Early Ordovician-Middle Silurian Subduction-Closure of the Proto-Tethys Ocean:Evidence from the Qiaerlong Pluton at the Northwestern Margin of the West Kunlun Orogenic Belt,NW China

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Journal of Earth Science 2024年第2期35卷 430-448页

作者： jinhong Xu Zhengwei Zhang Chengquan Wu Taiyi luo Weiguang Zhu Xiyao Li Ziru jin Pengcheng Hu State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550018China University of Chinese Academy of Sciences Beijing100049China

Early Paleozoic magmatism in the West Kunlun Orogenic Belt(WKOB)preserves important information about the tectonic evolution of the Proto-Tethys *** paper reports whole-rock compositions,zircon and apatite U-Pb dating,and zircon Hf isotopes for the Qiaerlong Pluton(QEL)at the northwestern margin of WKOB,with the aim of elucidating the petrogenesis of the pluton and shedding insights into the subduction-collision process of this oceanic *** QEL is mainly composed of Ordovician quartz monzodiorite(479±3 Ma),quartz monzonite(467–472 Ma),and syenogranite(463±4 Ma),and is intruded by Middle Silurian peraluminous granite(429±20 Ma)and diabase(421±4 Ma).Zirconε_(Hf)(t)values reveal that quartz monzodiorites(+2.1 to+9.9)and quartz monzonites(+0.6 to+6.8)were derived from a mixed source of juvenile crust and older lower crust,and syenogranites(−5.6 to+4.5)and peraluminous granites(−2.9 to+2.0)were generated from a mixed source of lower crust and upper crust;diabases had zirconε_(Hf)(t)values ranging from−0.3 to+4.1,and contained 463±5 Ma captured zircon and 1048±39 Ma inherited zircon,indicating they originated from enriched lithospheric mantle and were contaminated by crustal *** Ordovician granitoids are enriched in LILEs and light rare-earth elements,and depleted in HFSEs with negative Nb,Ta,P,and Ti anomalies,suggesting that they formed in a subduction *** Silurian peraluminous granites have the characteristics of leucogranites with high SiO_(2)contents(74.92 wt.%–75.88 wt.%)and distinctly negative Eu anomalies(δEu=0.03–0.14),indicating that they belong to highly fractionated granite and were formed in a post-collision extension *** analysis of these results with other Early Paleozoic magmas reveals that the Proto-Tethys ocean closed before the Middle Silurian and its southward subduction resulted in the formation of QEL.

关键词： subduction-closure Qiaerlong Pluton West Kunlun Orogen Proto-Tethys Ocean tectonics geochemistry

Magnetocaloric effect and phase transition critical behavior of La0.75Sr0.25Mn0.9Co0.1O3 compound synthesized under the high pressure

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Tungsten 2024年第3期6卷 621-632页

作者： jing Zhao Lei Gao Jian-Jun Zhao Wei Wei Hui-Qin Yun Ru Xing Huai-jin Ma Xiang jin luo-Meng Chao School of Physical Science and Technology Key Laboratory of Magnetism and Magnetic Materials for Higher Education in Inner Mongolia Autonomous Region Baotou Teachers' College National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths School of Physics and Electronic Information Inner Mongolia Normal University College of Science Inner Mongolia University of Science and Technology

In this study,a novel method is proposed for producing perovskite rare-earth manganese oxide magnetic refrigeration materials that exhibit superior properties compared to similar *** maximum magnetic entropy change values for this sample are 1.44 and 3.75 J·kg-1·K-1for magnetic fields of 2 and 7 T,***,its relative cooling power has been calculated to be 101.96 and 404.78 J·kg-1,indicating good *** results were obtained using the sample synthesized under a pressure of 4 GPa,and the sample has undergone a second phase *** critical behavior of the sample fits well with the mean field *** different magnetic fields,there is a significant overlap between the values of the maximum magnetic entropy change and the temperature-averaged entropy change,indicating that the refrigeration performance of the sample after high pressure can approach its maximum capability.

关键词： High-pressure synthesis Magnetocaloric effect Relative cooling power Magnetic phase transition

Global Marine Cold Seep Metagenomes Reveal Diversity of Taxonomy,Metabolic Function,and Natural Products

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 121-134页

作者： tao Yu Yingfeng luo Xinyu Tan Dahe Zhao Xiaochun Bi Chenji Li Yanning Zheng Hua Xiang Songnian Hu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Cold seeps in the deep sea are closely linked to energy exploration as well as global climate *** alkane-dominated chemical energy-driven model makes cold seeps an oasis of deep-sea life,showcasing an unparalleled reservoir of microbial genetic ***,by analyzing 113 metagenomes collected from 14 global sites across 5 cold seep types,we present a comprehensive Cold Seep Microbiomic Database(CSMD)to archive the genomic and functional diversity of cold seep *** CSMD includes over 49 million non-redundant genes and 3175 metagenome-assembled genomes,which represent 1895 species spanning 105 *** addition,beta diversity analysis indicates that both the sampling site and cold seep type have a substantial impact on the prokaryotic microbiome community *** and anaerobic metabolisms are prevalent in microbial communities,accompanied by considerable mixotrophs and facultative anaerobes,highlighting the versatile metabolic potential in cold ***,secondary metabolic gene cluster analysis indicates that at least 98.81%of the sequences potentially encode novel natural products,with ribosomally synthesized and post-translationally modified peptides being the predominant type widely distributed in archaea and ***,the CSMD represents a valuable resource that would enhance the understanding and utilization of global cold seep microbiomes.

关键词： Global marine cold seep Metagenome Prokaryotic microbiome Metabolic function Natural product

Complementary monogamy and polygamy properties among multipartite systems

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Chinese Physics B 2024年第3期33卷 207-213页

作者：李陶周静怡孙琪靳志祥梁登峰罗婷 School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China School of Computer Science and Techonology Dongguan University of TechnologyDongguan 523808China People's Public Security University of China Academy of Information Network SecurityBeijing 100038China

Monogamy and polygamy relations are essential properties of quantum entanglement,which characterize the distributions of entanglement in multipartite *** this paper,we establish the general monogamy relations forγ-th(0≤γ≤α,α≥1)power of quantum entanglement based on unified-(q,s)entanglement and polygamy relations forδ-th(δ≥β,0≤β≤1)power of entanglement of assistance based on unified-(q,s)entanglement of assistance,which provides a complement to the previous research in terms of different parameter regions ofγandδ.These results are then applied to specific quantum correlations,e.g.,entanglement of formation,Renyi-q entanglement of assistance and Tsallis-q entanglement of assistance to get the corresponding monogamy and polygamy ***,typical examples are presented for illustration.

关键词： monogamy relation polygramy relation

Karstsinnectes cehengensis(Cypriniformes:Nemacheilidae),a new species of cave fish from Guizhou,China

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Zoological Systematics 2024年第2期49卷 101-115页

作者： Xinrui Zhao Changting Lan tao luo jing Yu Jiajun Zhou Ning Xiao Jiang Zhou School of Karst Sciences Guizhou Normal UniversityGuiyang 550025China School of Life Sciences Guizhou Normal UniversityGuiyang 550001China Zhejiang Forest Resource Monitoring Center Hangzhou 310020China Zhejiang Forestry Survey Planning and Design Company Limited Hangzhou 310020China Guiyang Healthcare Vocational University Guiyang 550081China

Four species of the genus Karstsinnectes,which live in dark,low-energy groundwater ecosystems,are currently recorded,mainly distributed in the upstream of the Pearl River,the Youjiang River and the Hongshui *** biodiversity surveys is particularly difficult due to the particular cave habitats inhabited by these *** this work,we describe a new cave fish of the genus Karstsinnectes,namely *** luo,Zhao&Zhou,***.,collected from the Beipanjiang River,the upstream of the Hongshui ***,the four individuals of the new species form a phylogenetically separate lineage,as the sister clade of ***,with a 9.4–9.5%genetic difference in mitochondrial Cyt ***,the new species can be distinguished from its congeners by a combination of the following morphological characteristics:body naked,without body color;eyes reduced,diameter 1.4–3.8%of head length;anterior and posterior nostrils adjacent,anterior nostril not elongated to a barbel-like tip;lateral line incomplete;caudal fin forked;dorsal-fin rays iii-7,pectoral-fin rays i-11–12,pelvic-fin rays i-7,anal-fin rays iii-5,with 14 branched caudal-fin *** discovery of this new species represents the northernmost distribution of species within the genus Karstsinnectes and the first record from Guizhou *** currently known species of this genus inhabited in caves,making them ideal organisms for studying historical river connectivity and cave formation process.

关键词： Diversity karst cave morphology phylogeny Karstsinnectes

Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting Li Zhen-Yu Zhang De-Cun luo Bo-Yu Xu Rong-Jiang Zhang Ji-Long Yao Dan Li tao Xie Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)

Transient breathing dynamics during extinction of dissipative solitons in mode‑locked fiber lasers

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Frontiers of Optoelectronics 2024年第1期17卷 9-19页

作者： Zichuan Yuan Si luo Ke Dai Xiankun Yao Chenning tao Qiang Ling Yusheng Zhang Zuguang Guan Daru Chen Yudong Cui Hangzhou Institute of Advanced Studies Zhejiang Normal UniversityHangzhou 311231China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Optical Information Detection and Display Technology of Zhejiang Zhejiang Normal UniversityJinhua 321004China School of Physics Northwest UniversityXi’an 710127China

The utilization of the dispersive Fourier transformation approach has enabled comprehensive observation of the birth process of dissipative solitons in fiber ***,there is still a dearth of deep understanding regarding the extinction process of dissipative *** this study,we have utilized a combination of experimental and numerical techniques to thoroughly examine the breathing dynamics of dissipative solitons during the extinction process in an Er-doped mode-locked fiber *** results demonstrate that the transient breathing dynamics have a substantial impact on the extinction stage of both steady-state and breathing-state dissipative *** duration of transient breathing exhibits a high degree of sensitivity to variations in pump *** simulations are utilized to produce analogous breathing dynamics within the framework of a model that integrates equations characterizing the population inversion in a mode-locked *** results corroborate the role of Q-switching instability in the onset of breathing ***,these findings offer new possibilities for the advancement of various operational frameworks for ultrafast lasers.

关键词： Breathing soliton Fiber laser Dispersive Fourier transform Q-switched instability

Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： Yan-Peng Chen Ji-An Jiang Wen-tao luo Xian-Zhong Zheng Min Fang Chao Yang Yuan-Yu Hong Zong-Fei Lü Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs.

关键词： telescopes surveys Moon