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Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao wu Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. we compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 21-31页

作者： Lu Liu Xingyu wu Lufan Zhang Chuan wang School of Artificial Intelligence Beijing Normal University Applied Optics beijing Area Major Laboratory Beijing Normal University

The multi-class classification of images is a pivotal challenge within the realm of image processing. As the volume of visual data continues to expand, there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification tasks. However, many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques, where the requisite circuit measurements increase linearly with the volume of training data. This work introduces a novel approach for training a quantum image multi-classifier based on the quantum search algorithm. we have meticulously conducted rigorous experiments on a handwritten digit dataset, a classic benchmark in the field. The results have been meticulously compared with previous works, and the comparative analysis not only validates the efficiency of our proposed approach, requiring only O(N/b) measurements during training, but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

Nanostructured ZnO/biVO_(4)I-scheme heterojunctions for piezocatalytic degradation of organic dyes via harvesting ultrasonic vibration energy

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 488-497页

作者： Yiling Li Xiaoyao Yu Yingjie Zhou Yao Lin Ying wu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China

biVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step *** resulting ZnO/biVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine b(Rhb)unde mechanical vibrations,they exhibit superior activity compared to pure *** 40wt%ZnO/biVO_(4)heterojunction composite displayed the highest activity,along with good stability and *** enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole ***,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active ***,ZnO/biVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.

关键词： piezoelectric catalytic heterojunction dye degradation ultrasonic vibration

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Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-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 University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph 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

Mechanism Study on the Effect of Retarder on Polyurethane Setting Time based on Molecular Simulation

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 224-231页

作者： wu Yuxuan XU wenyuan YU Tianlai JI Yongcheng School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the b component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component b on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

关键词： polyurethane retarder setting time molecular dynamics diffusion coefficient

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Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou Chen Shen Zhenghao wu Xingying Lan Yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： Condensation reactions

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： bing wANG Xiaofeng TAO Shujun HAN Huici wu Kai YANG Zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-bS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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Advancements and Challenges in Organic–Inorganic Composite Solid Electrolytes for All‑Solid‑State Lithium batteries

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Nano-Micro Letters 2025年第1期17卷 46-97页

作者： Xueyan Zhang Shichao Cheng Chuankai Fu Geping Yin Liguang wang Yongmin wu Hua Huo State Key Laboratory of Space Power‑Sources School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China College of Chemical and biological Engineering Zhejiang UniversityHangzhou 310058People’s Republic of China State Key Laboratory of Space Power-Sources 2965 Dongchuan RoadMinhang DistrictShanghai 200240People’s Republic of China

To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming *** the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale ***,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their *** review provides a comprehensive overview of recent research advancements in ***,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically *** lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic ***,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of ***,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLbs.

关键词： Composite solid electrolytes Inorganic filler Interfacial stability Li-ion conduction mechanism Characterization techniques

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Synergistically S/N self-doped biochar as a green bifunctional cathode catalyst in electrochemical degradation of organic pollutant

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Green Energy & Environment 2025年第1期10卷 214-230页

作者： Xuechun wang Huizhong wu Jiana Jing Ge Song Xuyang Zhang Minghua Zhou Raf Dewil Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin300350China Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution Nankai UniversityTianjin300350China Tianjin Advanced water Treatment Technology International Joint Research Center College of Environmental Science and EngineeringNankai UniversityTianjin300350China Department of Chemical Engineering KU LeuvenJ.De Nayerlaan 5Sint-Katelijne-Waver B2860Belgium

biomass-derived heteroatom self-doped cathode catalysts has attracted considerable interest for electrochemical advanced oxidation processes(EAOPs)due to its high performance and sustainable ***,we illustrated the morphological fates of waste leaf-derived graphitic carbon(wLGC)produced from waste ginkgo leaves via pyrolysis temperature regulation and used as bifunctional cathode catalyst for simultaneous H_(2)O_(2) electrochemical generation and organic pollutant degradation,discovering S/N-self-doping shown to facilitate a synergistic effect on reactive oxygen species(ROS)*** the optimum temperature of 800℃,the wLGC exhibited a H_(2)O_(2) selectivity of 94.2%and tetracycline removal of 99.3%within 60 *** functional theory calculations and in-situ Fourier transformed infrared spectroscopy verified that graphitic N was the critical site for H_(2)O_(2) *** pyridinic N and thiophene S were the main active sites responsible for_OH generation,N vacancies were the active sites to produce ^(1)O_(2) from *** performance of the novel cathode for tetracycline degradation remains well under a wide pH range(3–11),maintaining excellent stability in 10 *** is also industrially applicable,achieving satisfactory performance treating in real water *** system facilitates both radical and non-radical degradation,offering valuable advances in the preparation of cost-effective and sustainable electrocatalysts and hold strong potentials in metal-free EAOPs for organic pollutant degradation.

关键词： biochar S and N self-doping H_(2)O_(2)production In-situ FTIR Metal-free electrochemical advanced oxidation processes