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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-Xiao Meng Xing-yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun Ma Bao Du Yong-qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations

Contribution of fungal biomass to persistent soil carbon across natural ecosystems

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Science China Earth Sciences 2025年

作者： Xiang WANG Guang-Hui yu Yakov KUZYAKOV Bo-Hao YIN Andreas KAPPLER Cong-qiang LIU Bohai Coastal Critical Zone National Observation and Research Station Institute of Surface-Earth System Science School of Earth System Science Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim Tianjin University Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil Science University of G?ttingen Agro-Technological Institute Peoples Friendship University of Russia (RUDN University) Geomicrobiology Center for Applied Geosciences University of Tübingen Cluster of Excellence EXC 2124 Controlling Microbes to Fight Infection University of Tübingen

Fungi are known to be crucial in the formation and stabilization of soil organic matter through their exudates and dead residues (necromass). Yet, it remains unclear how fungi contribute to the persistence of carbon in soils over millennial scales across biomes. Here, this study fills the knowledge gap by linking fungal carbon stocks with minerals-associated carbon stocks across major biomes. A strong correlation between fungal biomass and reactive mineral-associated carbon stocks in soils across six biomes supports the substantial role of fungi in soil carbon persistence at the global level. High spatial resolution nanoscale secondary ion mass spectrometry revealed that fungi may stabilize carbon by forming organo-mineral associations through their close physical connection to reactive minerals and weathered nanoparticles. We propose a conceptual model that emphasizes the dualistic role of hypha-mineral interactions:(i) fungi accelerate organic matter decomposition by producing reactive oxygen species on the hypha-mineral interfaces, and (ii) fungi stabilize their residues on mineral surfaces, leading to millennial scale persistence of soil C. Concluding, fungi play a fundamental role in ecosystems that extends beyond the decomposition of persistent carbon. They are crucial in stabilizing carbon on mineral surfaces, thereby facilitating the long-term removal of carbon from rapid biotic cycling.

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Mechanical properties and microstructures of Mg-6Si alloys fabricated using the tungsten-inert-gas arc additive manufacturing

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China Foundry 2025年

作者： Peng-cheng Zhou Guo-qiang You Jin-yu Feng Lei Wang Xiao Lin Bin Jiang College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University National Key Laboratory of Advanced Casting Technologies Chongqing University

Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases,which can result in inferior material *** this study,Mg-6wt.%Si （Mg-6Si） alloy was prepared by wire arc additive manufacturing （WAAM）,employing the gas tungsten arc welding technique with rapid *** microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal *** results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast *** microhardness of the WAAM Mg-6Si increases by 36.6%in comparison to that of as-cast Mg-6Si ***,the average tensile strengths at room temperature and 150°C increases by 63.4%and 21.3%,*** refines both the Mg2Si phase and the overall grains,resulting in a homogeneous morphology and improved mechanical *** granular Mg2Si phase,characterized by fine particles with a diffused distribution,shows a significant increase in *** acicular Mg2Si phase is distributed along the grain boundaries,and its concentration significantly *** average grain size of the Mg2Si phase is about 9.20μm,about 5 times *** refinement and distribution of the granular Mg2Si phase,as well as the reduction in the amount of needle-like Mg2Si particles,are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.

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Electrocatalytic nitrite reduction to ammonia on isolated bismuth alloyed ruthenium

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Journal of Energy Chemistry 2025年第1期100卷 369-376页

作者： Shiyao Shang Fuzhou Wang Zeyi Sun Chaofan qiang Ke Chu School of Materials Science and Engineering Lanzhou Jiaotong University

Electrochemical reduction of NO2-to NH3（NO2-RR） is recognized as an appealing approach for achieving renewable NH3synthesis and waste ***,we report isolated Bi alloyed Ru （Bi1Ru） as an efficient NO2-RR *** calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO2-activation and suppress proton adsorption,while accelerating the NO2-RR protonation energetics to render a high NO2--to-NH3conversion ***,Bi1Ru assembled in a flow cell delivers an NH3yield rate of 1901.4μmol h-1cm-2and an NH3-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA *** study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO2-RR catalysts toward the ammonia electrosynthesis.

关键词： Ammonia

Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong Liu qiang Zhou yuxiao Lin Xinsheng Zhao Guangmin Zhou Xiaoxiao Li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials

Composite-mask GAN based on refined optical flow and disparity map for SLAM visual odometry

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Optoelectronics Letters 2025年

作者： JI yuehui JIANG Jingwei LIU Junjie SONG yu GAO qiang School of Electrical Engineering and Automation， Tianjin University of Technology Tianjin Key Laboratory of Control Theory and Application for Complex Systems

Although deep learning methods have been widely applied in slam visual odometry over the past decade with impressive improvements， the accuracy remains limited in complex dynamic environments. In this paper， a composite mask-based generative adversarial network is introduced to predict camera motion and binocular depth maps. Specifically， a perceptual generator is constructed to obtain the corresponding parallax map and optical flow from between two neighboring frames. Then， an iterative pose improvement strategy is proposed to improve the accuracy of pose estimation. Finally， a composite mask is embedded in the discriminator to sense structural deformation in the synthesized virtual image， thereby increasing the overall structural constraints of the network model， improving the accuracy of camera pose estimation， and reducing drift issues in the Visual Odometer. Detailed quantitative and qualitative evaluations on the KITTI dataset show that the proposed framework outperforms existing conventional， supervised learning and unsupervised depth VO methods， providing better results in both pose estimation and depth estimation.

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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： qiang Liu Xiang Li Shen Du Ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

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Constraints on what controls millennial-scale basin-wide denudation across mountain belts, Asia

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Science China Earth Sciences 2025年第1期68卷 74-93页

作者： Ye YANG Steven A.BINNIE Sheng XU Cong-qiang LIU Tibor J.DUNAI Institute of Surface-Earth System Science School of Earth System Science Tianjin University Institute of Geology and Mineralogy University of Cologne

The terrestrial cosmogenic nuclide dataset consisting of 123310Be measurements of fluvial sediment samples across the Asian mountain belts is used to constrain the influence of climate,tectonics and topography on Earth-surface denudation processes.10Be-derived basin-wide denudation rates were recalculated using a Monte Carlo simulation approach that relied on pixel-by-pixel production *** rates derived span four orders of magnitude,from 7.4±0.7 mm kyr-1（1σ;Central Tibetan Plateau） to 9,646744+777mm kyr-1（1σ;Southern Tibetan Plateau）,with a median of 186 mm *** our results with the traditional basin-wide production rate scaling model using a centroid coordinate and mean elevation,suggests that 96.6%of production rates will be underestimated using the latter method,especially for basins with a large *** bias between both methods reaches as large as 40%,caused by basin hypsometry and the nonlinear scaling of production rate with elevation and *** of the correlations between uniformly recalculated denudation rates and tectonics,climate,topography and rock lithology will facilitate the extrapolation of denudation rates in unknown basins using available *** the perspective of local scales,precipitation coupled with neotectonics-driven landslides is likely the most influential factor in subtropical Taiwan Island,while topography primarily constrains surface denudation rates in the eastern Tibetan Plateau within a narrow range of *** highland regions with glacier coverage,such as the Pamir,central and southern Tibetan Plateau high denudation rates are affected by glaciation,whereas lower precipitation and high erosion base level may limit river incision and evolving relief in the Central Tibetan *** contrast to local-scale findings highlighting a dominant factor constraining denudation rate,our large-scale quantitative analyses across the Asian mountain belts finds that （1） topographic metrics including

关键词： 10Be-derived denudation rate Climate change Tectonic uplift Topographic gradient Asian mountains

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing Guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

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