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hydration ***:Modelling implications for Fe-Ti oxide crystallisation in mafic intrusions,with specific reference to the Panzhihua intrusion,SW China

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Geoscience Frontiers 2013年第5期4卷 555-569页

作者： geoffrey h.howarth Stephen A.Prevec Geology Department Rhodes UniversityP.O.Box 94Grahamstown 6140South Africa

Recent work on the Panzhihua intrusion has produced two separate models for the crystallisation of the intrusion：（1） low-Ti,high CaO and low h2O（0.5 wt.%） parent magma（equivalent to Emeishan low-Ti basalt） at FMQ;and（2） high-Ti,low CaO and higher h2O（＆gt;1.5 wt.%） parent magma（equivalent to Emeishan high-Ti basalt） at FMQ ＋ *** of these parent magma compositions produces significantly different results. We present here detailed f（O2） and h2O modelling for average compositions of both Emeishan high-Ti and low-Ti ferrobasalts in order to constrain the effects on crystallisation sequences for Emeishan ultra-mafic -mafic layered *** is consistent with numerous experimental studies on ferro-basaltic magmas from other localities（*** intrusion）.Modelling is compared with the geology of the Panzhihua intrusion in order to constrain the crystallisation of the gabbroic rocks and the Fe-Ti oxides ore *** suggest that the gabbroic rocks at the Panzhihua intrusion can be best explained by crystallisation from a parent magma similar to that of the high-Ti Emeishan basalt at moderate h2O contents（0.5-1 wt.%） but at the lower end of TiO2 content for typical high-Ti basalts（2.5 wt.%TiO2）. Distinct silicate disequilibrium textures in the Fe-Ti oxide ore layers suggest that an influx of h2O may be responsible for changing the crystallisation *** increase in h2O during crystallisation of gabbroic rocks will result in the depression of silicate liquidus temperatures and resultant disequilibrium with the *** cooling of the magma with high h2O then results in precipitation of Mt-Uv alone. The h2O content of parent magmas for mafic layered intrusions associated with the ELIP is an important variable.h2O alters the crystallisation sequence of the basaltic magmas so that at high h2O and f（O2） Mt -Uv crystallises earlier than plagioclase and ***,the addition of h2O to an anhydrous magma can explain silicate dis

关键词： f(O2) h2O Panzhihua Parent magma Fe-Ti oxide ore Petrogenesis

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Kaapvaal lamproite melts(aka orangeites):A new type of alkalicarbonate liquid?insights from olivine-hosted multiphase inclusions(Silvery home,South Africa)

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Geoscience Frontiers 2024年第5期15卷 308-322页

作者： Adam Abersteiner Alexey Tarasov Alexander Golovin geoffrey h.howarth Vadim S.Kamenetsky Department of Geosciences and Geography Research Programme of Geology and Geophysics(GeoHel)University of HelsinkiFinland Institute for Sustainability Energy and ResourcesThe University of AdelaideAdelaide SA-5005Australia Department of Earth Sciences School of Physical SciencesThe University of AdelaideAdelaide SA-5005Australia V.S.Sobolev Institute of Geology and Mineralogy Siberian Branch Russian Academy of SciencesRussia Department of Geological Sciences University of Cape TownRondebosch 7701South Africa Center of Deep Sea Research Institute of OceanologyChinese Academy of Sciences266071 QingdaoChina

Kaapvaal lamproites(aka orangeites)are a group of volatile-rich(h_(2)O,CO_(2)),micaceous,ultrapotassic igneous rocks that are unique to the Kaapvaal craton in southern ***,the composition of the melts that give rise to these rocks remains poorly understood due to overprinting effects of contamination by mantle and crustal material,volatile exsolution,fractional crystallisation and post-magmatic ***,this lack of reliable data on the initial composition of the Kaapvaal lamproite melts hampers our understanding of their source,petrogenesis and ascent *** is a common mineral comprising the Kaapvaal lamproites that has both xenocrystic(i.e.,mantle)and magmatic *** inclusions(melt/fluid)entrapped within olivine have been consistently demonstrated as an effective tool for gaining fundamental insights into the composition and evolution of melts that produce both kimberlites and lamproites,prior to processes,such as eruption,devolatization and syn-/post-magmatic *** this study,multiphase inclusions of both secondary and pseudosecondary origin hosted in olivine from a Kaapvaal lamproite(Silvery home,South Africa)provide novel insights into the composition of the melt(s)that initially transported olivine to the surface and then crystallised after emplacement to form the lamproite *** inclusions in our study contain daughter mineral assemblages consisting of diverse Ca-Mg carbonates,including K-,Na-,Ba-,and Sr-bearing varieties,moderate K-rich silicates(phlogopite,tetraferriphlogopite),and subordinate oxides,phosphates,sulphides,sulphates,and *** on these daughter mineral assemblages,we suggest that the composition of the melt entrapped by olivine was SiO_(2)-poor,Ca-Mg carbonate-rich and contained elevated concentrations of K,Na,Ba,Sr,P and *** mineral and reconstructed melt compositions are in stark contrast to the mineral association of the groundmass and the bulk-rock composition

关键词： Lamproite Kaapvaal Multiphase inclusions Olivine Orangeite

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Assimilation of carbonate country rock by the parent magma of the Panzhihua Fe-Ti-V deposit(SW China):Evidence from stable isotopes

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Geoscience Frontiers 2013年第5期4卷 547-554页

作者： Clement Ganino Chris harris Nicholas T.Arndt Stephen A.Prevec geoffrey h.howarth Geoazur Universite de Nice-Sophia AntipolisCNRS/IRD250 rue Albert Einstein 06560 ValbonneFrance Department of Geological Sciences University of Cape TownRondebosch 7701South Africa ISTerre Grenoble UniversitesCNRS/IRD BP 53 38041 Grenoble CEDEX 9France Department of Geology Rhodes UniversityGrahamstown 6140South Africa

The Panzhihua intrusion in southwest China is part of the Emeishan Large Igneous Province and host of a large Fe-Ti-V ore *** emplacement of the main intrusion,multiple generations of mafic dykes invaded carbonate wall rocks,producing a large contact *** measured the oxygen-isotope composition of the intrusions,their constituent minerals,and samples of the country *** and plagioclase from Panzhihua intrusion haveδ18O values that are consistent with magmatic equilibrium, and formed from magmas withδ18O values that were 1-2‰higher than expected in a mantle-derived *** unmetamorphosed country rock has highδ18O values,ranging from 13.2‰（sandstone） to 24.6-28.6‰（dolomite）.The skarns and marbles from the aureole have lowerδ18O andδ13C values than their protolith suggesting interaction with fluids that were in exchange equilibrium with the adjacent mafic magmas and especially the numerous mafic dykes that intruded the *** would explain the alteration ofδ18O of the dykes which have significantly higher values than expected for a mantle-derived *** on the exactδ18O values assumed for the magma and contaminant, the amount of assimilation required to produce the elevatedδ18O value of the Panzhihua intrusion was between 8 and 13.7 wt.%,assuming simple *** exact mechanism of contamination is unclear but may involve a combination of assimilation of bulk country rock,mixing with a melt of the country rock and exchange with CO2-rich fluid derived from decarbonation of the marls and *** mechanisms,particularly the latter,were probably involved in the formation of the Fe-Ti-V ores.

关键词： Panzhihua Stable isotopes Carbonates Assimilation Contamination

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Two stages of immiscible liquid separation in the formation of Panzhihua-type Fe-Ti-V oxide deposits,SW China

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Geoscience Frontiers 2013年第5期4卷 481-502页

作者： Mei-Fu Zhou Wei Terry Chen Christina Yan Wang Stephen A.Prevec Patricia Pingping Liu geoffrey h.howarth Department of Earth Sciences The University of Hong Kong Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences Department of Geology Rhodes University

Magmatic oxide deposits in the～260 Ma Emeishan Large Igneous Province（ELIP）,SW China and northern Vietnam,are important sources of Fe,Ti and *** giant magmatic Fe-Ti-V oxide deposits, such as the Panzhihua,hongge,and Baima deposits,are well described in the literature and are hosted in layered mafic-ultramafic intrusions in the Panxi region,the central *** same type of ELIP- related deposits also occur far to the south and include the Anyi deposit,about 130 km south of Panzhihua,and the Mianhuadi deposit in the Red River fault *** Anyi deposit is relatively small but is similarly hosted in a layered mafic *** Mianhuadi deposit has a zircon U-Pb age of～260 Ma and is thus contemporaneous with the *** deposit was variably metamorphosed during the Indosinian orogeny and Red River ***,magnetite of the Mianhuadi deposit contains smaller amounts of Ti and V than that of the other deposits,possibly attributable to the later *** distribution of the oxide ore deposits is not related to the domal structure of the *** major feature of all the oxide deposits in the ELIP is the spatial association of oxide-bearing gabbroic intrusions,syenitic plutons and high-Ti flood ***,we propose that magmas from a mantle plume were emplaced into a shallow magma chamber where they were evolved into a field of liquid immiscibility to form two silicate liquids,one with an extremely Fe-Ti-rich gabbroic composition and the other *** immiscible Fe-Ti-（P） oxide melt may then separate from the mafic magmas to form oxide *** parental magmas from which these deposits formed were likely Fe-Ti-rich picritic in composition and were derived from enriched asthenospheric mantle at a greater depth than the magmas that produced sulfide-bearing intrusions of the ELIP.

关键词： Fe-Ti oxide Gabbroic layered intrusion Immiscible Fe-Ti-(P) rich melt Emeishan Large Igneous Province SW China

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The development of policy approaches for reducing nitro-gen pollution to coastal waters of the USA

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Science China(Life Sciences) 2005年第z2期48卷 791-806页

作者： Robert W.howarth Department of Ecology & Evolutionary Biology Cornell University NY 14853USA

Two-thirds of the coastal rivers and bays in the United States are degraded from nutrient pollution, and nitrogen inputs these waters continue to increase. The nitrogen comes from a variety of sources, including runoff from agricultural fields, concentrated animal feeding operations, atmospheric deposition from fossil fuel combustion, and sewage and septic wastes. Technical solutions for nitrogen pollution exist at reasonable cost. That most of these solutions have not yet been implemented to any significant extent across the United States suggests that new policy approaches are necessary. The best solution may involve a combination of voluntary and mandatory approaches, applying different approaches to different sources of nitrogen pollution. A watershed-based approach that relies heavily on voluntary mechanisms (such as crop-yield insurance to reduce over-fertilization) is likely to be the most effective for some sources of nitrogen (such as runoff from agricultural fields), while a uniform national regulatory approach may be better for others (such as NOx emissions from fossil fuel combustion). Implementation of management strategies should be carefully coupled to monitoring programs to assess the effectiveness of these strategies. While both nitrogen and phosphorus are important to control, the focus should be on nitrogen management, in part because nitrogen is more generally the causal agent of coastal eutrophication. Also, while nitrogen-control practices tend to also reduce phosphorus pollution, phosphorus-control practices often have little effect on nitrogen. Although current scientific and technical knowledge is sufficient to begin to make substantial progress toward solving coastal nitrogen pollution, progress will be made more quickly and more cost effectively with increased investment in appropriate scientific research.

关键词： development of policy approaches, reducing nitrogen pollution, coastal water of the USA.

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The use of environmentally sustainable bio-derived solvents in solvent extraction applications——A review

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Chinese Journal of Chemical Engineering 2016年第2期24卷 215-220页

作者： Zheng Li Kathryn h.Smith geoffrey W.Stevens Particulate Fluids Processing Centre Department of Chemical and Biomolecular EngineeringThe University of Melbourne

Replacement of volatile organic compounds （VOCs） by greener or more environmentally sustainable solvents is becoming increasingly important due to the increasing health and environmental concerns as well as economic pressures associated with VOCs. Solvents that are derived from biomass, namely bio-derived solvents, are a type of green solvent that have attracted intensive investigations in recent years because of their advantages over con- ventional VOCs, such as low toxicity, biodegradability and renewability. This review aims to summarize the use of bio-derived solvents in solvent extraction applications, with special emphasis given to utilization of biodiesels and terpenes. Compared with the conventional VOCs, the overall performance of these bio-derived solvents is comparable in terms of extraction yields and selectivity for natural product extraction and no difference was found for metal extraction. To date most researchers have focused on laboratory scale thermodynamics studies. Future work is required to develop and test new bio-derived solvents and understand the kinetic performance as well as solvent extraction nilnt nlant studies.

关键词： Solvent extraction Bio-derived solvents Green solvents Biodiesels Terpenes

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Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

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Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

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Do mantle plumes exist？

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Episodes 2006年第3期29卷 162-168页

作者： Ian h. Campbell geoffrey F. Davies Research School of Earth Sciences The Australian National University Canberra ACT 0200 Australia

The physics of low Reynolds number plumes is well understood, which allows a number of testable predictions to be made about mantle plumes. They are predicted to originate from the core-mantle boundary and consist of a large head followed by a narrower tail. Millions of cubic kilometers of magma can be produced from a plume head. Rifting over a previously-emplaced plume head should produce a narrow zone of thickened oceanic crust along the rift margin. Initial eruption from a plume head should be preceded by -1,000 m of domal uplift. Picrites are expected to dominate the first eruptive products of a new plume and should be concentrated near the centre of the volcanic province. All of these predictions are confirmed by observations, and so provide strong support for the validity of the mantle plume hypothesis.

关键词：地幔热流柱数值模型俯冲作用深部构造

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Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

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