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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

Weak KAM theory for two classes of almost periodic Hamiltonian systems

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Science China Mathematics 2025年

作者： Xun Niu Kaizhi Wang Yong Li School of Mathematics and Statistics Center for Mathematics and Interdisciplinary SciencesNortheast Normal University School of Mathematical sciences Shanghai Frontier Science Center of Modern Analysis (CMA-Shanghai)Shanghai Jiao Tong University Institute of Mathematics Jilin University

The purpose of this paper is to investigate the dynamics of Bohr almost periodic and Levitan almost periodic Hamiltonian systems via the weak KAM theory. We obtain minimal measures and weak KAM solutions in both cases. The weak KAM solution is a weak solution to the Hamilton-Jacobi equation, which formally transforms the original Hamiltonian systems into an integrable one. Consequently, we get the existence of an invariant torus in the aforementioned weak sense.

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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the Chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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Science China Earth sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space sciences University of Science and Technology of China CAS center of Excellence in Comparative Planetary Studies

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell domain. The five tectonic convective modes are non-plate mobile-lid, plate-like mobile-lid, episodic plate-like mobile-lid, episodic stagnant-lid, and stagnant-lid convective modes, respectively. The typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness, mobility, and their standard deviations are presented and discussed. The results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress, the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five modes. Additionally, as the Rayleigh number increases, the range of yield stress for the platelike mobile-lid convective mode decreases, and the dimensionless transition stress between different tectonic modes ***, the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number, but decreases between other tectonic modes. Furthermore, we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate, with the transition stress decreasing as the internal heating rate increases. The fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa, which aligns with the strength of serpentinized mantle rock determined by experimental petrography. If the Archean mantle was 300°C warmer than it is today, then the Earth was in an episodic stagnant-lid convective mode. The tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal evolution. If the lithospheric strength w

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Simulation and analysis of the long-term impacts of 1.5°C global climate pledges on China's land systems

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Science China Earth sciences 2025年

作者： Jiaying LV Changqing SONG Yifan GAO Sijing YE Peichao GAO State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University center for GeoData and analysis Beijing Normal University

Global warming has become a shared issue for humanity. At the 26th Conference of the Parties to the United Nations Framework Convention on Climate Change in 2021, participating countries reached climate pledges aimed at making more proactive contributions to limit the global average temperature rise within 1.5°C by 2100. Land system changes are significant responses of land to climate change. As one of the contracting parties, China has proposed climate targets such as carbon peaking and carbon neutrality goals in recent years to support the global pledges of limiting global warming to1.5°C, which will profoundly impact China's future land system changes. This study focuses on China as the study area,produces data with a thematic resolution of 27 types of land systems, integrates the output of various land types by the Global Change Assessment Model(GCAM) into four categories of land service demand, and combines these with the improved CLUMondo model to simulate China's land system changes in 2100 under a 1.5°C global warming scenario and a reference scenario without updated emission reduction measures. The conclusions of this study are as follows:(1) The method of integrating the GCAM and improved CLUMondo model demonstrates high validation accuracy in simulating China's land system changes, effectively predicting the changes.(2) Under the 1.5°C global warming scenario, the quality of ecosystems related to mountains, water, forests, farmland, lakes, and grasslands in China improved. The areas of shrubland, wetland, and forest are projected to increase by 185%, 79%, and 33%, respectively, with low-density shrubland, high-density wetland, and high-density forest showing the most significant increases.(3) Compared with the reference scenario, the 1.5°C climate pledges drive greater changes in future land systems, with wetland and forest area growth levels exceeding those of the reference scenario by 20% and 10%, respectively. Notably, the changes in cropland, grasslan

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Piriformospora indica confers cadmium tolerance in Nicotiana tabacum

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Journal of environmental sciences 2015年第11期27卷 184-191页

作者： Feiqiong Hui Jian Liu Qikang Gao Binggan Lou Institute of Biotechnology Zhejiang University China Tobacco Guizhou Industrial Co. Ltd. analysis center of agrobiology and environmental sciences Zhejiang University

Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance against biotic and abiotic stresses. In order to confirm the influence of P. indica on growth, proline, malondialdehyde（MDA）, chlorophyll, and cadmium（Cd） amounts in Nicotiana tabacum under Cd stress, hydroponics, pot and field trials were conducted. The results showed that P. indica can store Cd in plant roots and reduce leaf Cd content, reduce the concentration of MDA, and increase the proline and chlorophyll content and the activities of catalase, peroxidase, and superoxide dismutase under hydroponic Cd stress. RT-PCR analysis showed that the relative expression level of genes Gsh2, Ta PCS1, oas1, GPX, and Hsp70 in colonized plants was 4.3, 1.4, 2.9, 1.7, and 6.9fold higher than in un-colonized plants respectively. Cd exposure significantly reduced un-colonized plants＇ agronomic traits compared to P. indica-colonized ones. Our results suggested that P. indica can sequester Cd in roots, so that much less cadmium was transported to leaves, and the increased concentrations of antioxidant enzymes, pigments and proline contents, as well as the higher expression of stress-related phytochelatin biosynthesis genes in P. indica-inoculated plants, may also serve to protect N. tabacum plants against oxidative damage, enhancing Cd tolerance.

关键词： Plant endophytic fungus Malondialdehyde Proline Chlorophyll Stress-related genes Tobacco plants

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FSD1 inhibits glioblastoma diffuse infiltration through restriction of HDAC6-mediated microtubule deacetylation

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Science China Life sciences 2025年

作者： Dake Xiao Haowen Ran Lishu Chen Yuanyuan Li Yan Cai Songyang Zhang Qinghui Qi Huiran Wu Cheng Zhang Shuailiang Cao Lanjuan Mi Haohao Huang Ji Qi Qiuying Han Haiqing Tu Huiyan Li Tao Zhou Fangye Li Ailing Li Jianghong Man Nanhu Laboratory National Center of Biomedical Analysis School of Traditional Chinese Medicine Capital Medical University Department of Neurosurgery General Hospital of Central Theater Command of Chinese PLA School of Life and Health sciences Huzhou College Department of Neurosurgery Beijing Fengtai Hospital Department of Neurosurgery First Medical Center of PLA General Hospital

The infiltration of glioblastoma multiforme(GBM) is predominantly characterized by diffuse spread, contributing significantly to therapy resistance and recurrence of GBM. In this study, we reveal that microtubule deacetylation, mediated through the downregulation of fibronectin type III and SPRY domain-containing 1(FSD1), plays a pivotal role in promoting GBM diffuse infiltration. FSD1 directly interacts with histone deacetylase 6(HDAC6) at its second catalytic domain, thereby impeding its deacetylase activity on α-tubulin and preventing microtubule deacetylation and depolymerization. This inhibitory interaction is disrupted upon phosphorylation of FSD1 at its Ser317 and Ser324 residues by activated CDK5, leading to FSD1 dissociation from microtubules and facilitating HDAC6-mediated α-tubulin deacetylation. Furthermore, increased expression of FSD1 or interference with FSD1 phosphorylation reduces microtubule deacetylation, suppresses invasion of GBM stem cells, and ultimately mitigates tumor infiltration in orthotopic GBM xenografts. Importantly, GBM tissues exhibit diminished levels of FSD1 expression, correlating with microtubule deacetylation and unfavorable clinical outcomes in GBM patients. These findings elucidate the mechanistic involvement of microtubule deacetylation in driving GBM cell invasion and offer potential avenues for managing GBM infiltration.

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The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & Research center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing