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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu yang li Yu liu Xiao-Xiao ling li-Guang Wu li yang Lan yang Bo yang Yong-Gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen yang Qiao-sheng Xia Cun-Hong Yin Dong-Peng Hua College of Mechanical Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy(PMPEA) exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni_3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics(MD) simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni_3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic(BCC) phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

Exploration of cyclooxygenase-2 inhibitory peptides from walnut dreg proteins based on in silico and in vitro analysis

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Food Science and Human Wellness 2024年第3期13卷 1636-1644页

作者： Zishan Hong Jing Xie liang Tao Jing-Jing Dai Tingting li li Zhang Yuying Bai Xia Hu Jinlian Chen Jun sheng yang Tian College of Food Science and Technology Yunnan Agricultural UniversityKunming 650201China Yunnan Provincial Key Laboratory of Precision Nutrition and Personalized Food Manufacturing Yunnan Agricultural UniversityKunming 650201China Engineering Research Center of Development and Utilization of Food and Drug Homologous Resources Ministry of EducationYunnan Agricultural UniversityKunming 650201China School of Tea and Coffee Pu’er UniversityPu’er 665000China Yunnan Provincial Engineering Research Center for Edible and Medicinal Homologous Functional Food Yunnan Agricultural UniversityKunming 650201China Key Laboratory of Pu-er Tea Science Ministry of EducationYunnan Agricultural UniversityKunming 650201China

Walnut dreg protein hydrolysates(WDPHs)exhibit a variety of biological activities,however,the cyclooxygenase-2(COX-2)inhibitory peptide of WDPHs remain *** aim of this study was to rapidly screen for such peptides in WDPHs through a combination of in silico and in vitro *** total,1262 peptide sequences were observed by nano liquid chromatography/tandem mass spectrometry(nano LC-MS/MS)and 4 novel COX-2 inhibitory peptides(AGFP,FPGA,LFPD,and VGFP)were *** kinetic data indicated that AGFP,FPGA,and LFPD displayed mixed-type COX-2 inhibition,whereas VGFP was a non-competitive *** is mainly because the peptides form hydrogen bonds and hydrophobic interactions with residues in the COX-2 active *** results demonstrate that computer analysis combined with in vitro evaluation allows for rapid screening of COX-2 inhibitory peptides in walnut protein dregs.

关键词： Walnut dreg proteins Cyclooxygenase-2 inhibitory peptide Identification Virtual screening Molecular docking

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear Science and Techniques 2024年第5期35卷 74-84页

作者： sheng-Jie Du Xiu-Xia li yang Tian Yuan-Yuan liu Ke Jia Zhong-Zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan li Zheng-Cao li Sha-Sha Lv College of Nuclear Science and Technology Joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment Key Laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： Xiao-Di li Shu-sheng li Xu-Bao Jiang Xiao-li Zhu Xiang Zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent *** this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl *** was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence *** effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were *** fluorescence emission was ascribed to CTE *** addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of *** study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release

Anti-inflammatory germacrane-type sesquiterpene lactones from Vernonia sylvatica

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Chinese Journal of Natural Medicines 2024年第6期22卷 568-576页

作者： WANG Min li Han HU Bintao TANG Chunping XU Hui KE Changqiang XIE Zuoquan YE yang YAO sheng State Key Laboratory of Drug Research&Natural Products Research Center Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China School of life Science and Technology Shanghai Tech UniversityShanghai 201210China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan 528400China

Nine new germacranolides,sylvaticalides A−H(1-9),and three known analogues(10-12)were isolated from the aeri-al part of Vernonia *** structures were established using comprehensive spectroscopic analysis,including high-resolution electrospray ionization mass spectroscopy(HR-ESI-MS)and 1D and 2D nuclear magnetic resonance(NMR)*** absolute configurations were determined by X-ray diffraction *** anti-inflammatory activities of all isolated compounds were as-sessed by evaluating their inhibitory effects on the nuclear factor kappa B(NF-κB)pathway,which was activated by lipopolysacchar-ide(LPS)-stimulated human THP1-Dual cells,and the interferon-stimulated gene(ISG)pathway,activated by STING agonist MSA-2 in the same cell *** 1,2 and 6 showed inhibitory effects on the NF-κB and ISG signaling pathways,with IC_(50)values ranging from 4.12 to 10.57μmol·L^(−1).

关键词： Vernonia sylvatica Germacrane-type sesquiterpene lactone Sylvaticalides A−H Anti-inflammatory NF-κB path-way ISG pathway

Dark energy and matter interacting scenario to relieve H_(0) and S_(8) tensions

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Chinese Physics C 2024年第5期48卷 1-7页

作者：高立场薛社生张鑫 Key Laboratory of Cosmology and Astrophysics(liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Kapteyn Astronomical Institute University of GroningenP.O.Box 8009700 AV Groningenthe Netherlands ICRANet Piazzale della Repubblica10-65122PescaraItaly ICTP-AP University of Chinese Academy of SciencesBeijing 100049China Physics Department Sapienza University of RomeP.le A.Moro 500185RomeItaly INFN Sezione di PerugiaVia A.PascoliI-06123PerugiaItaly Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

We consider a new cosmological model(calledΛCDM),in which the vacuum energy interacts with matter and radiation,and test this model using the current cosmological *** the CMB+BAO+SN(CBS)dataset to constrain the model,we find that H_(0) and S_(8) tensions are relieved to 2.87σand 2.77σ,***,in this case,theΛCDM model is not favored by the data,compared withΛ*** find that when the H_(0) and S_(8) data are added to the data combination,the situation is significantly *** the CBS+H_(0) case,the model relieves the H_(0) tension to 0.47σ,and the model is favored overΛ*** the CBS+H_(0)+S_(8) case,we obtain a synthetically best situation,in which the H_(0) and S_(8) tensions are relieved to 0.72σand 2.11σ,*** this case,the model is most favored by the ***,this cosmological model can greatly relieve the H_(0) tension and simultaneously effectively alleviate the S_(8) tension.

关键词： dark energy interacting dark energy model the Hubble constant Hubble tension cosmological constraint

Study of 26 Galactic Open Clusters with Extended Main-sequence Turnoffs

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Research in Astronomy and Astrophysics 2024年第6期24卷 28-37页

作者： yang-yang Deng Zhong-Mu li Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Institute of Astronomy and Information Dali UniversityDali 671003China

Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so far is limited,and the reasons for their formation are still *** work identifies 26 Galactic OCs with undiscovered eMSTOs and investigates the causes of these *** population types and fundamental parameters of cluster samples are acquired using CMD fitting *** them,the results of 11 OCs are reliable as the observed CMDs are *** propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO *** results also show that the impact of age spread is important,as it can adequately explain the structure of young OCs and fit the observed CMDs of intermediate-age OCs better.

关键词： (stars:)binaries:general Galaxy:fundamental parameters (Galaxy:)open clusters and associations:general (stars:)Hertzsprung Russell and C-M-diagrams

Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-sheng HAO Yan WANG Lan-Hai li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(plier ***,average and maximum snow depths increased along with an increase in peak snow water equivalent,thus indicating a higher frequency of extremely scarce or abundant snow *** low snowpack temperature gradient and earlier snowmelt dates in spring lead to earlier occurrences of snowmelt floods and wet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains