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Classification and progress of extraction technologies for nonferrous metal resources

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Science China Chemistry 2025年第2期68卷 458-474页

作者： Fangqin Cheng Na Zhou Nazeer Muhammad Nouman Li Cui Caixia Yin institute of Resources and Environmental Engineering State Environmental Protection Key Laboratory of Efficient Utilization of Coal Waste ResourcesShanxi UniversityTaiyuan 030006China Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular ScienceShanxi UniversityTaiyuan 030006China

In recent years,the demand for strategic metal resources,essential for scientific and technological progress and industrial development,has *** a stable supply of these metals is critical to national security and the well-being of the *** global industrialization accelerates,the daily demand for nonferrous metals continues to ***,extracting and recovering strategic metals from low-grade raw materials,such as solid waste,has become crucial for maintaining their supply and economic ***,the extraction process is fraught with challenges,including mineral phase stability and complex *** review focuses on key strategic metals such as lithium,aluminum,gallium,and *** introduces and examines various methods for extracting nonferrous metals from different raw materials,including traditional mining technologies applied to low-grade solid *** also outlines future development opportunities and challenges in this field.

关键词： nonferrous metal extraction classification and progress

Effects of photo-oxidation and transition metals on the formation of reactive oxygen species from aromatic compounds using spectroscopic method

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Journal of Environmental Sciences 2025年第5期151卷 1-11页

作者： Xiaoyu Hu Juanjuan Qin Yuanyuan Qin Tianyi Zhao Yuxuan Cao Qinghe Cai Lijia Zhang Yang Zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Beijing Yanshan Earth Critical Zone National Research Station Beijing 101408China Resource and Environmental Branch China National Institute of StandardizationHaidian DistrictBeijing 100191China Binzhou institute of Technology Binzhou 256606China

Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental *** study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ***-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic ***-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic *** different interactions were due to complexation between ACs and *** photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with *** study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to *** former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen *** study revealed that both interactions among components and photo-oxidation significantly influenced ROS *** studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts.

关键词： Reactive oxygen species Aromatic compounds Transitional metals Photo-oxidation

Extraction of rare earth elements from neodymium(NdFeB) magnet scrap using magnesium halides

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Journal of Rare Earths 2025年第2期43卷 371-376,I0006页

作者： Sung Gue Heo Jae Yeol Yang Soong Ju Oh Seok-Jun Seo Mi Hye Lee Kyoung-Tae Park Korea institute for Rare Metals Korea Institute of Industrial TechnologyIncheonRepublic of Korea Department of Materials Science and Engineering Korea UniversitySeoulRepublic of Korea

The demand for neodymium(NdFeB) permanent magnets for electric vehicles and eco-friendly generators is ***,NdFeB magnets contain rare earth elements(REEs),which are limited in *** this study,we performed an exchange reaction between magnesium halides(fluoride and chloride) and waste NdFeB scrap and then compared the characteristics of the extracted halides *** compositions of the ternary Mg fluoride(LiF:NaF:MgF_(2)=50:40:10 in mole ratio) and chloride(LiCl:NaCl:MgCl_(2)=10:50:40 in mole ratio) salts were thermodynamically determined for achieving low eutectic *** reactions between the NdFeB scrap powder(1-2 mm) and Mg halide salts were carried out at 1073 and 873 K for the fluoride and chloride systems,respectively,in an argon *** the reaction,we separated Nd halide from the residual salt and evaluated the Ndextraction *** phase formation of the salt was analyzed using X-ray diffraction(XRD),and the extraction rate of Nd was analyzed using inductively coupled plasma optical emission spectroscopy(ICPOES).Nd was extracted in the form of Nd halide(NdF_(3) or NdCl_(3)),and the extraction rates in the fluoride and chloride systems are 98.64% and 84.59%,***,the fluoride system is more effective than the chloride system for Nd *** study provides a comprehensive comparative analysis of the effectiveness of fluo ride and chlo ride systems in extracting REEs from NdFeB magnet *** study findings can be used to develop an effective method for recycling magnet scraps.

关键词： Rare earth elements Neodymium magnet Nd extraction Magnesium halide Metal-scrap recycling Fluoride system

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Stem-leaf saponins of Panax notoginseng attenuate experimental Parkinson's disease progression in mice by inhibiting microglia-mediated neuroinflammation via P2Y2R/PI3K/AKT/NFκB signaling pathway

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Chinese Journal of Natural Medicines 2025年第1期23卷 43-53页

作者： Hui Wu Chenyang Ni Yu Zhang Yingying Song Longchan Liu Fei Huang Hailian Shi Zhengtao Wang Xiaojun Wu Shanghai Key Laboratory of Compound Chinese Medicines The Ministry of Education (MOE) Key Laboratory for Standardization of Chinese Medicines Institute of Chinese Materia Medica The MOE Innovation Centre for Basic Medicine Research on Qi-Blood TCM Theories Shanghai University of Traditional Chinese Medicine

Stem-leaf saponins from Panax notoginseng(SLSP) comprise numerous PPD-type saponins with diverse pharmacological properties; however, their role in Parkinson's disease(PD),characterized by microglia-mediated neuroinflammation, remains unclear. This study evaluated the effects of SLSP on suppressing microglia-driven neuroinflammation in experimental PD models, including the 1-methyl-4-phenylpyridinium(MPTP)-induced mouse model and lipopolysaccharide(LPS)-stimulated BV-2 microglia. Our findings revealed that SLSP mitigated behavioral impairments and excessive microglial activation in models of PD, including MPTP-treated mice. Additionally, SLSP inhibited the upregulation of inducible nitric oxide synthase(i NOS) and cyclooxygenase-2(COX2) and attenuated the phosphorylation of PI3K,protein kinase B(AKT), nuclear factor-κB(NFκB), and inhibitor of NFκB protein α(IκBα) both in vivo and in vitro. Moreover, SLSP suppressed the production of inflammatory markers such as interleukin(IL)-1β, IL-6, and tumor necrosis factor alpha(TNF-α) in LPS-stimulated BV-2cells. Notably, the P2Y2R agonist partially reversed the inhibitory effects of SLSP in LPStreated BV-2 cells. These results suggest that SLSP inhibit microglia-mediated neuroinflammation in experimental PD models, likely through the P2Y2R/PI3K/AKT/NFκB signaling pathway. These novel findings indicate that SLSP may offer therapeutic potential for PD by attenuating microglia-mediated neuroinflammation.

关键词： Microglia NFκB Neuroinflammation P2Y2 receptor Stem-leaf saponins of Panax Notoginseng

Enhancing anion conductivity in a highly alkali-stable eta topologic Cu(Ⅰ) framework via strong electrostatic repulsion

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Science China Chemistry 2025年

作者： Xiaolu Wang Shaohui Guo Chao Suo Fuqiang Zhang Junhao Wang Wenjing Wang Daqiang Yuan Linfeng Liang Xianming Zhang College of Chemistry Taiyuan University of Technology institute of Crystalline Materials Shanxi University School of Chemistry and Materials Science Shanxi Normal University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Metal-organic frameworks （MOFs） based on anion exchange membranes （AEMs） have garnered considerable interest,particularly for their potential to enhance ion conductivity by pre-introducing anions into *** approach is recognized as straightforward and effective for improving ion ***,developing high-performance AEMs is limited by the inherent instability and low resistance of *** study presents a novel 1,3,5-triazineμ3-bridged neutral Cu（I） framework,designated SXU-120 （where SXU represents shanxi University）.This framework is synthesized using melamine,a widely available industrial product,as the starting material,achieving a high space-time yield exceeding 1.1 kg *** organic ligands and metal ions in SXU-120 are 3-connected,forming a rare eta topology with the point symbol 8～***-120 exhibits exceptional stability,even in a 10 M KOH solution,due to its high density of uncoordinated–NH2and carbonyl ***,the framework’s unique one-dimensional channels,characterized by their electronegativity,interact electrostatically with OH-ions,thereby accelerating OH-ion transfer along these ***,the OH-conductivity of this material reaches an impressive 0.49 S cm-1at 90°C under full humidity for 100 h,representing the highest OH-conductivity reported for MOF-based conductors to *** properties make SXU-120 a promising candidate for efficient AEM materials in next-generation industrial applications.

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A Three-Dimensional SPH Simulation of Lander Footpad Impact on a Lunar Regolith Bed

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Computer Modeling in Engineering & Sciences 2025年第2期142卷 2045-2066页

作者： Wanqing Yuan Huiying Xie Can Huang Xiaoliang Wang Qingquan Liu Department of Mechanics School of Aerospace EngineeringBeijing Institute of TechnologyBeijing100081China institute of Computational Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China institute of Large Structures for Advanced industrial Equipment Beijing Institute of TechnologyZhuhai519088China

Landing spacecraft experience significant impact forces during landing,resulting in large deformation and failure in the soil surface,which severely affects landing safety and *** paper establishes a smoothed particle hydrodynamics(SPH)model based on the theory of soil elastoplastic constitutive relations to describe the process of a lander’s footpad impacting lunar regolith *** model can provide engineering indices such as impact load and penetration depth,and illustrate the large deformation and crater characteristics of the regolith.A detailed analysis of the response of the footpad and lunar regolith during landing reveals that the process can be broadly divided into two stages of rapid penetration and oscillatory ***,there are significant similarities in the landing process under different landing velocities and footpad *** research investigates the large deformation and crater characteristics of the lunar regolith *** results demonstrate two failure modes in the *** the impact of a footpad with a smaller mass,the final failure surface of the regolith exhibits a bowl-shaped profile with a uniformly open *** contrast,under the impact of a footpad with a larger mass,the final failure surface of the regolith presents an urn-shaped profile with a large abdomen and a small ***,the impact craters in both scenarios show a bowl-like *** cases of high-velocity impacts,the impact crater exhibits obvious blocky spalling on its *** SPH model developed in this study can be applied to predict the large deformation and failure response of lunar soil under the impact of rigid structures as well as the impact load and penetration *** effectively predicts the dynamic response of the landing process,which is expected to provide a reference for engineering design.

关键词： SPH footpad load lunar regolith impact crater

Lattice-mismatch-induced formation of defect-rich Pd-Cu alloy nanocages for enhanced formic acid oxidation activity

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Science China Chemistry 2025年第2期68卷 481-491页

作者： Zhaojun Liu Zhengyan Wang Zhaoyu Wang Hao Yuan Yuke Bai Xiaoxiao Wang Zerui Mu Chunxia Wu Kai Liu Zhun Hu Chuanbo Gao Sate Key Laboratory of Multiphase Flow in Power Engineering Frontier Institute of Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China institute of industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Crystallographic defects in noble metal nanocrystals are recognized as highly active catalytic sites,significantly enhancing activities in many important *** their importance,synthesizing noble metal nanocrystals with a high density of defects poses a considerable synthetic ***,we present a novel lattice mismatch-induced formation mechanism to create high-density defects in noble metal *** approach takes advantage of lattice mismatch to enable nonepitaxial nucleation and growth of a noble metal on a foreign metal substrate,forming abundant noble metal crystallites with random lattice orientations not dictated by the substrate *** these crystallites grow extensively,they merge,forming numerous grain boundaries and yielding defect-rich noble metal ***-rich alloy nanocrystals can also be synthesized through a subsequent vacancy-diffusion alloying *** take defective PdCu alloy nanocages as an example and demonstrate the effectiveness of crystallographic defects in enhancing catalytic performance of noble metal *** nanocages exhibit superior activity in the electrocatalytic formic acid oxidation reaction,which is 1.6 times greater than their defect-free *** strategy offers a new avenue for creating defect-rich noble metal nanocrystals as highly efficient catalysts for a wide array of catalytic applications.

关键词： noble metal nanocrystals defects non-epitaxial growth electrocatalysis formic acid oxidation reaction

Upcycling of polyphenylene oxide into 2,6-dimethyl aniline via depolymerization and amination over a Pt/CeO_(2) catalyst

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Science China Chemistry 2025年第2期68卷 520-525页

作者： Shengchao Jia Wenke Zhao Xiaohui Liu Yong Guo Yanqin Wang State Key Laboratory of Green Chemical Engineering and industrial Catalysis Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Upcycling of plastic waste into N-containing compound is a novel and attractive strategy for its disposal and will opens up a promising direction for the production of value-added ***,an efficient strategy for the depolymerization-amination of polyphenylene oxide(PPO)into 2,6-dimethyl aniline is developed over a simple Pt/CeO_(2) *** C–O linkages of PPO can be selectively broken,producing 2,6-dimethyl phenol and then hydrogenated and aminated to 2,6-dimethyl cyclohexylamine over the Pt/CeO_(2) ***,2,6-dimethyl aniline was produced with high selectivity through the dehydrogenation of 2,6-dimethyl cyclohexylamine in the same *** can be used as the hydrogen-acceptor in the dehydrogenation step and enhance the selectivity of target *** N-containing compound,2,6-dimethyl aniline,is obtained and separated after HCl ***,the Pt/CeO_(2) catalyst exhibit remarkable stability and can sustainably catalyze the synthesis of 2,6-dimethyl aniline in several cycles.

关键词： PPO depolymerization-amination 2,6-dimethyl aniline Pt/CeO_(2)

Optimizing canopy-spacing configuration increases soybean yield under high planting density

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The Crop Journal 2025年第1期13卷 233-245页

作者： Ruidong Li Cailong Xu Zongsheng Wu Yifan Xu Shi Sun Wenwen Song Cunxiang Wu institute of Crop Sciences Chinese Academy of Agricultural Sciences/National soybean Industrial Technology R&D CenterBeijing 100081China

Dense cropping increases crop yield but intensifies resource competition,which reduces single plant yield and limits potential yield *** canopy spacing could enhance resource utilization,support crop morphological development and increase ***,a three-year study was performed to verify the feasibility of adjusting row spacing to further enhance yield in densely planted *** three row-spacing configurations(40-40,20-40,and 20-60 cm)and two planting densities(normal 180,000 plants ha 1 and high 270,000 plants ha 1).The differences in canopy structure,plant morphological development,photosynthetic capacity and their impact on yield were *** spacing configurations have a significant effect on canopy transmittance(CT).The 20-60 cm row spacing configuration increased CT and creates a favorable canopy light environment,in which plant height is reduced,while branching is *** approach reduces plant competition,optimizes the developments of leaf area per plant,specific leaf area,leaf area development rate,leaf area duration and photosynthetic physiological indices(Fv/Fm,ETR,Pn).The significant increase of 11.9%-34.2%in canopy apparent photosynthesis(CAP)is attributed to the significant optimization of plant growth and photosynthetic physiology through CT,an important contributing factor to yield *** yield in the 20-60 cm treatment is 4.0%higher than in equidistant planting under normal planting density,but 5.9%under high density,primarily driven by CAP and pod *** findings suggest that suitable row spacing configurations optimize the light environment for plants,promote source-sink transformation in soybeans,and further improve *** practice,a 20-60 cm row spacing configuration could be employed for high-density soybean planting to achieve a more substantial yield gain.

关键词： Soybean Planting density Row-spacing configuration Canopy transmittance Yield