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地壳岩浆氧化性和斑岩型铜矿床成矿潜力

中国科学:地球科学 2025年第1期 227-238页

作者：艾宇民 massimo CHIARADIA 吴超陈华勇中国科学院广州地球化学研究所矿物学与成矿学重点实验室中国科学院大学 Department of Earth Sciences University of Geneva 广东省矿物物理与材料研究开发重点实验室

斑岩型铜矿床是全球铜(Cu)、钼(Mo)和金(Au)资源的主要供应源,其形成过程受到多种地质因素的控制,尤其是岩浆的氧化性是当前研究的焦点.本文综合分析了全球范围内已发表的弧岩浆中钒(V)和钪(Sc)的比值(V/Sc)数据,并收集了V和Sc在矿物和... 详细信息

斑岩型铜矿床是全球铜(Cu)、钼(Mo)和金(Au)资源的主要供应源,其形成过程受到多种地质因素的控制,尤其是岩浆的氧化性是当前研究的焦点.本文综合分析了全球范围内已发表的弧岩浆中钒(V)和钪(Sc)的比值(V/Sc)数据,并收集了V和Sc在矿物和硅酸盐熔体中的分配系数.通过探讨V/Sc比值与岩浆氧逸度(f O2)之间的相关性,评估了不同厚度弧地壳中岩浆的氧化性特征.研究结果表明,磁铁矿的分离结晶是降低残余岩浆的V/Sc比值的关键因素.此外,磁铁矿结晶开始时的镁值(Mg#)与岩浆氧化性呈现显著的正相关性.利用这一规律,进一步评估第四纪弧岩浆的氧化性,发现在地壳厚度超过20km的成熟岛弧和大陆弧中,岩浆随着地壳厚度的增加趋向于更高的氧逸度.这表明在这些环境中,石榴石和角闪石的地壳内分异作用增强了岩浆的氧化性;相比之下,地壳厚度小于20km的薄弧中的岩浆则可能由于更多的俯冲板片氧化性物质输入,展现出比厚弧岩浆更高的氧化性.这些发现表明,俯冲动力学和地壳厚度在决定弧岩浆氧化性及其形成斑岩型铜矿的能力方面起着至关重要的作用.高度氧化的原始弧岩浆由于在岩浆演化的早期阶段经历磁铁矿结晶,从而导致硫化物饱和,这一过程导致铜的早期亏损,因此不利于斑岩型铜矿的形成.相反,在厚弧中磁铁矿结晶被广泛抑制,使硫化物大量饱和出现在岩浆晚期阶段,因此更有利于保留演化岩浆中铜的成矿潜力.本研究深入探讨了地壳内分异作用和俯冲带物质输入对弧岩浆氧化性的双重影响,并基于V/Sc比值变化规律的系统研究,为斑岩型铜矿床的成矿潜力提供了新的地球化学指示.

关键词：岩浆演化 V/Sc变化规律磁铁矿氧逸度斑岩铜矿

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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 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（<20 km）, 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

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Gelation of polymeric nanoparticles

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Particuology 2014年第3期12卷 1-11页

作者： Hua Wu massimo Morbidelli Institute for Chemical and Bioengineering.Department of Chemistry and Applied Biosciences ETH Zurich8093 ZurichSwitzerland

We review how, starting from polymeric nanoparticles, to generate clusters of fractal morphology and to expand the entire space and interconnect to form gels, through either Brownian motion or intense shear-induced aggregation. In the case of Brownian motion-induced gelation, specific techniques developed to obtain uniform structure of gels under both reaction-limited and diffusion-limited cluster aggregation conditions have been described. In the case of intense shear-induced gelation as a newly developed technique, our focus is on its principle, theoretical development and advantages with respect to Brownian motion-induced gelation in practical applications. We consider gelation of both rigid and soft particles. As a physical process, the bonding between the particles within gels is owed to van der Waals attractions, thus being easily broken. However, in the case of soft particles that can coalesce upon contact, the coalescence can allow the particles to stick together forming permanent gels. In this case, the gel structure can be controlled by controlling the degree of coalescence. Techniques used to control the degree of coalescence have also been described.

关键词： Structured material Fractal Gelation Gel Polymer

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HITS hits art

Blockchain(Research and Applications) 2021年第4期2卷 64-70页

作者： massimo Franceschet Department of Mathematics Computer Science and PhysicsUniversity of UdineVia delle Scienze 206Udine33100Italy

The blockchain art market is partitioned around the roles of artists and collectors and highly concentrated among a few prominent *** hence propose to adapt Kleinberg's authority/hub HITS(Hyperlink-Induced Topic Search)method to rate artists and collectors in the art *** seems a reasonable choice since the original method deftly defines its scores in terms of a mutual recursive relationship between authorities/artists—the miners of information/art,and hubs/collectors—the assemblers of such information/*** evaluated the proposed method on the collector-artist network of SuperRare gallery,the major crypto art *** found that the proposed artist and collector metrics are weakly correlated with other networks science metrics like degree and *** hints at the possibility of coupling different measures in order to profile active users of the gallery and suggests investment strategies with different risk/reward ratios for collectors as well as marketing strategies with different targets for artists.

关键词： Blockchain Non-fungible tokens Crypto art Network science Centrality measures

Influence of Tectonics and Morphometric Features on the Landslide Distribution: A Case Study from the Mesima Basin (Calabria, South Italy)

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Journal of Earth Science 2020年第2期31卷 393-409页

作者： massimo Conforti Fabio Ietto National Research Council Institute for Agricultural and Forest Systems in the MediterraneanRendeCSItaly University of Calabria Department of BiologyEcology and Earth ScienceArcavacata di RendeCSItaly

Identifying the instability areas provides useful information about the recognition of the vulnerable zones and,thus,helps to potentially decrease the harm to the infrastructure and the hazard conditions in inhabited *** this regard,morphometric parameters and tectonic setting are widely employed in mapping,modelling and understanding of instability *** present study is aimed to analyse the combined effects of slope morphometry(slope gradient,slope curvature,local relief),of lithology,of drainage density and of tectonic setting on the distribution of *** study area is located in the Mesima Basin that lies in the central part of the Calabria region(southern Italy).The morphometric analysis was carried out by geographic information system(GIS)techniques,whereas the geomorphic attributes were computed by a digital elevation model(DEM).The recognized landslides and faults were digitized and stored in a GIS geo-database that allowed the construction of relative density maps.A total of 1991 landslides and 231 tectonic lineaments were recognized and *** distribution of the collected data suggests that the occurrence of landslides is not ***,the research highlights as the lithology,the fault density,the slope gradient and the local relief play an important role in determining the landslide *** used approach is aimed to reinforce the knowledge about the validity of the application of morphometric analysis to the landslide *** Mesima Basin is a poorly studied area of the Calabria from a geomorphological ***,previous researches focused mainly on geological and on tectonic aspects,as well as on instability phenomena in the Mesima ***,this paper takes a step forward with respect to previous studies because it augments the knowledge about the relationship between faults,morphometric features and the occurrence of landslide.

关键词： terrain analysis faults drainage network landslide GIS

What do we know about the role of lncRNAs in multiple sclerosis?

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Neural Regeneration Research 2021年第9期16卷 1715-1722页

作者： Viviana Nociti massimo Santoro Institute of Neurology Fondazione Policlinico Universitario‘A.Gemelli’IRCCSUniversitàCattolica del Sacro CuoreRomeItaly IRCCS Fondazione Don Carlo Gnocchi FlorenceItaly

Multiple sclerosis is a chronic, inflammatory and degenerative disease of the central nervous system of unknown aetiology although well-defined evidence supports an autoimmune pathogenesis. So far, the exact mechanisms leading to autoimmune diseases are still only partially understood. We know that genetic, epigenetic, molecular, and cellular factors resulting in pathogenic inflammatory responses are certainly involved. Long non-coding RNAs(lncRNAs) are non-protein coding transcripts longer than 200 nucleotides that play an important role in both innate and acquired immunity, so there is great interest in lncRNAs involved in autoimmune diseases. The research on multiple sclerosis has been enriched with many studies on the molecular role of lncRNAs in the pathogenesis of the disease and their potential application as diagnostic and prognostic biomarkers. In particular, many multiple sclerosis fields of research are based on the identification of lncRNAs as possible biomarkers able to predict the onset of the disease, its activity degree, its progression phase and the response to disease-modifying drugs. Last but not least, studies on lncRNAs can provide a new molecular target for new therapies, missing, so far, a cure for multiple sclerosis. While our knowledge on the role of lncRNA in multiple sclerosis has recently improved, further studies are required to better understand the specific role of lncRNAs in this neurological disease. In this review, we present the most recent studies on molecular characterization of lncRNAs in multiple sclerosis disorder discussing their clinical relevance as biomarkers for diagnosis and treatments.

关键词： antisense lncRNAs enhancer lncRNAs epigenetics immune system intergenic lncRNA intronic lncRNA multiple sclerosis sense lncRNAs single nucleotide polymorphisms

The interplay between non-esterified fatty acids and bovine peroxisome proliferator-activated receptors: results of an in vitro hybrid approach

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Journal of Animal Science and Biotechnology 2021年第1期12卷 292-304页

作者： Sebastiano Busato massimo Bionaz Department of Animal and Rangeland Sciences Oregon State UniversityCorvallisORUSA

Background: In dairy cows circulating non-esterified fatty acids(NEFA) increase early post-partum while liver and other tissues undergo adaptation to greater lipid metabolism, mainly regulated by peroxisome proliferator-activated receptors(PPAR). PPAR are activated by fatty acids(FA), but it remains to be demonstrated that circulating NEFA or dietary FA activate bovine PPAR. We hypothesized that circulating NEFA and dietary FA activate PPAR in dairy ***: The dose-response activation of PPAR by NEFA or dietary FA was assessed using HP300 e digital dispenser and luciferase reporter in several bovine cell types. Cells were treated with blood plasma isolated from Jersey cows before and after parturition, NEFA isolated from the blood plasma, FA released from lipoproteins using milk lipoprotein lipase(LPL), and palmitic acid(C16:0). Effect on each PPAR isotype was assessed using specific synthetic ***: NEFA isolated from blood serum activate PPAR linearly up to ~ 4-fold at 400 μmol/L in MAC-T cells but had cytotoxic effect. Addition of albumin to the culture media decreases cytotoxic effects of NEFA but also PPAR activation by ~ 2-fold. Treating cells with serum from peripartum cows reveals that much of the PPAR activation can be explained by the amount of NEFA in the serum(R~2 = 0.91) and that the response to serum NEFA follows a quadratic tendency, with peak activation around 1.4 mmol/L. Analysis of PPAR activation by serum in MAC-T, BFH-12 and BPAEC cells revealed that most of the activation is explained by the activity of PPARδ and PPARγ, but not PPARα. Palmitic acid activated PPAR when added in culture media or blood serum but the activation was limited to PPARδ and PPARα and the response was nil in serum from post-partum cows. The addition of LPL to the serum increased > 1.5-fold PPAR ***: Our results support dose-dependent activation of PPAR by circulating NEFA in bovine, specifically δand γ isotypes. Data also support the

关键词： Albumin Blood serum Bovine Gene reporter Hepatocytes Lipoprotein lipase Mammary cells Non-esterified fatty acids Peroxisome proliferator-activated receptor

Phase diagram of muonium hydride:the significant effect of dimensionality

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Communications in Theoretical Physics 2024年第2期76卷 182-187页

作者： Jieru Hu massimo Boninsegni Department of Physics University of Alberta State Key Laboratory of Precision Spectroscopy East China Normal University

We carry out a theoretical investigation of the low-temperature phase diagram of muonium hydride in two dimensions,using numerical *** is shown that the phase diagram of this substance is qualitatively different in two and three ***,while in three dimensions it is essentially identical to that of parahydrogen,i.e.,only displaying a single(crystalline)*** two dimensions it is very similar to that of^(4)He,with an equilibrium liquid phase that turns superfluid at a temperature as high as~2.2 K,and crystallizes under applied *** is a well-described case of a continuous-space condensed matter system whose ground state equilibrium phase is qualitatively altered by dimensional reduction.

关键词： quantum fuids and solids quantum Monte Carlo phase diagrams

Global-in-time Uniform Convergence for Linear Hyperbolic-Parabolic Singular Perturbations

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1161-1170页

作者： Marina GHISI massimo GOBBINO Universitàdegli Studi di Pisa Dipartimento di Matematicavia M.Buonarroti 256127 PISAItaly Universitàdegli Studi di Pisa Dipartimento di Matematica Applicata "Ulisse Dini"via Bonanno 25/B56126 PISAItaly

We consider the Cauchy problem εu^″ε ＋ δu′ε ＋ Auε = 0, uε（0） = uo, u′ε（0） = ul, where ε 〉 0, δ 〉 0, H is a Hilbert space, and A is a self-adjoint linear non-negative operator on H with dense domain D（A）. We study the convergence of （uε） to the solution of the limit problem ,δu＇＋ Au = 0, u（0） = u0. For initial data （u0, u1） ∈ D（A1/2）× H, we prove global-in-time convergence with respect to strong topologies. Moreover, we estimate the convergence rate in the case where （u0, u1）∈ D（A3/2） ∈ D（A1/2）, and we show that this regularity requirement is sharp for our estimates. We give also an upper bound for ｜u′ε（t）｜ which does not depend on ε.

关键词： Parabolic equations Damped hyperbolic equations Singular perturbations