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Improving Model Chain Approaches for Probabilistic Solar Energy Forecasting through Post-processing and Machine Learning

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Advances in Atmospheric Sciences 2025年第2期42卷 297-312页

作者： Nina HORAT Sina KLERINGS Sebastian LERCH institute of Statistics Karlsruhe Institute of TechnologyKarlsruhe 76185Germany Heidelberg institute for Theoretical studies Heidelberg 69118Germany

Weather forecasts from numerical weather prediction models play a central role in solar energy forecasting,where a cascade of physics-based models is used in a model chain approach to convert forecasts of solar irradiance to solar power *** simulations from such weather models aim to quantify uncertainty in the future development of the weather,and can be used to propagate this uncertainty through the model chain to generate probabilistic solar energy ***,ensemble prediction systems are known to exhibit systematic errors,and thus require post-processing to obtain accurate and reliable probabilistic *** overarching aim of our study is to systematically evaluate different strategies to apply post-processing in model chain approaches with a specific focus on solar energy:not applying any post-processing at all;post-processing only the irradiance predictions before the conversion;post-processing only the solar power predictions obtained from the model chain;or applying post-processing in both *** a case study based on a benchmark dataset for the Jacumba solar plant in the U.S.,we develop statistical and machine learning methods for postprocessing ensemble predictions of global horizontal irradiance(GHI)and solar power ***,we propose a neural-network-based model for direct solar power forecasting that bypasses the model *** results indicate that postprocessing substantially improves the solar power generation forecasts,in particular when post-processing is applied to the power *** machine learning methods for post-processing slightly outperform the statistical methods,and the direct forecasting approach performs comparably to the post-processing strategies.

关键词： solar forecasting post-processing probabilistic forecasting machine learning model chain

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU institute of Ecological Conservation and Restoration Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Desertification Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China institute of Great Green Wall Bayan Nur015200China Satellite Application Centre for Ecology and Environment MEEBeijing100094China institute of Microelectronics Chinese Academy of SciencesBeijing100029China Aerospace Information Research institute Chinese Academy of SciencesBeijing100094China institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution(VHR)unmanned aerial vehicle(UAV)and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover(FWVC)and fractional herbaceous vegetation cover(FHVC)in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error(RMSE)values for the FWVC and FHVC models were 10.69%and 11.67%,and the R^(2)values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10^(6)*** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy Land a

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Nickel-catalyzed ligand-controlled switchable skeletal rearrangements:divergent synthesis of isoquinoline-1,3-diones,cyclohexenols,cycloheptenols,and 2-benzazepin-5-ones

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Science China Chemistry 2025年

作者： Yongli Liu Yuanyuan Ping Wangqing Kong The institute for Advanced studies (IAS) Wuhan University

Skeleton diversity is an important feature of compound libraries and plays a key role in the success of biological ***-controlled divergent synthesis can transform the same substrate into different molecular skeletons, which not only can endow compound libraries with diverse biological activities but also reveal new catalytic modes, and therefore has received extensive attention. Herein, we disclose a Ni-catalyzed, ligand-controlled switchable skeletal rearrangement reaction of acryloyl o-bromobenzamides and activated alkenes. In this protocol, modification of the ligand backbone allows the conversion of the same starting material into four structurally distinct scaffolds of pharmacological importance. Specifically, the use of terpyridine ligand favors the 6-exo cyclization and subsequent 1,2-acyl/Ni dyotropic rearrangement to generate highly functionalized cyclohexenols, while the sterically hinderediPrPDI ligand facilitates the 6-exo cyclization and subsequent 1,2-aryl/Ni dyotropic rearrangement to form highly functionalized cycloheptenols. Furthermore, isoquinoline-1,3-diones were obtained through alkene diarylation in the absence of additional activated alkenes. More strikingly, the bidentate ligand promotes nucleophilic addition of the aryl halides to the amide carbonyl, followed by 1,4-acyl transfer and cross-coupling to afford 2-benzazepin-5-ones.

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Liquid metal catalyst for ammonia synthesis at low pressure

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Science China Materials 2025年第2期68卷 681-682页

作者： Ziyue Zeng Chenyang Wang Lei Fu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China The institute for Advanced studies Wuhan UniversityWuhan 430072China

Liquid metal(LM)has attracted immense interest as a novel catalyst in the past few years for its distinctive physicochemical properties,encompassing superior electrical and thermal conductivities,as well as exceptional fluidity characteristics at low temperatures[1].In contrast to conventional solid heterogeneous catalysts,the fluidic characteristics of liquid metal catalysts enhance the interaction between catalysts and reactants,boosting mass transfer at the reaction interface.

关键词： catalyst ammonia synthesis

Relativistic two-fluid hydrodynamics with quantized vorticity from the nonlinear Klein–Gordon equation

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Communications in Theoretical Physics 2025年第2期77卷 161-171页

作者： Chi Xiong Kerson Huang Minjiang Collaborative Center for Theoretical Physics Minjiang University institute of Advanced studies & School of Physical and Mathematical Science Nanyang Technological University Physics Department Massachusetts Institute of Technology Cambridge

We consider a relativistic two-fluid model of superfluidity, in which the superfluid is described by an order parameter that is a complex scalar field satisfying the nonlinear Klein–Gordon equation(NLKG). The coupling to the normal fluid is introduced via a covariant current–current interaction, which results in the addition of an effective potential, whose imaginary part describes particle transfer between superfluid and normal fluid. Quantized vorticity arises in a class of singular solutions and the related vortex dynamics is incorporated in the modified NLKG,facilitating numerical analysis which is usually very complicated in the phenomenology of vortex filaments. The dual transformation to a string theory description(Kalb–Ramond) of quantum vorticity, the Magnus force, and the mutual friction between quantized vortices and normal fluid are also studied.

关键词： relativistic superfluidity nonlinear Klein-Gordon field theory quantized vortices two-fluid model Kalb-Ramond field global string

Recent progress in exploring heterogeneous catalyst surface chemistry with near ambient pressure XPS

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Science China Chemistry 2025年

作者： Yuanjie Xu Zemin An Yu Tang institute of Molecular Engineering Plus Institute of Molecule Catalysis and In Situ/Operando Studies College of Chemistry Fuzhou University

X-ray photoelectron spectroscopy(XPS) is a crucial surface analysis technique that has become a key tool in the study of heterogeneous catalysis. Detecting surface chemistry under conditions that closely mimic actual industrial catalytic processes is essential for understanding the mechanisms involved. In the past decade, near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) has been increasingly utilized to study the surface chemistry of catalysts during heterogeneous catalytic processes, offering insights into structure-performance correlations. This review begins with a brief overview of NAP-XPS instrumentation. Next, we discuss the application of NAP-XPS in the study of thermal catalysis reactions, followed by a summary of the research on catalyst restructuring under reaction conditions. Additionally, we address the challenges and future perspectives for the development and application of NAP-XPS. Catalysis is inherently dynamic, requiring an understanding of the real-time behavior of catalysts under varying conditions. Therefore, future improvements in the ability to probe reaction intermediates with higher spatial and temporal resolution under conditions that closely mimic industrial environments are needed.

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A Sustainable Table

Beijing Review 2025年第4期68卷 18-19页

作者： Zhang Jiaolong Department for International and Strategic studies China Institute of International Studies

In a world undergoing profound transformations,food security stands as a cornerstone of peace and development-a vital foundation for building a community with a shared future for *** this backdrop,China has deepened i... 详细信息

关键词： corners Table peace

Drones for Development Cooperation with China can support the development of the low-altitude economy in Africa

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ChinAfrica 2025年第3期17卷 34-36页

作者： EHIZUELEN MICHAEL MITCHELL OMORUYI Centre for Nigeria studies Institute of African StudiesZhejiang Normal University

As an emerging industry catering to diverse needs across commercial,industrial,civil,and military fields,the low-altitude economy has the potential to transform industries such as logistics,transportation,tourism,heal... 详细信息

关键词： altitude economy Africa

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes:accessingβ-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期68卷 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang Xiaoyu Zhou Wei Xiao Jie Wu School of Pharmaceutical and Chemical Engineering&institute for Advanced studies Taizhou UniversityTaizhou 318000China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The generation of variousβ-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is *** method features a broad substrate scope and excellent *** studies reveal that the dispersion interaction between sulfinyl group and CH_(2)SO_(2)Ph group plays a crucial role in the stereoselectivity control.

关键词： β-chiral sulfones chiral cyclic sulfinamides sulfur dioxide insertion asymmetric radical cyclization stereoselectivity