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The thermal conductivity of the earth's core and implications for its thermal and compositional evolution

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National science Review 2021年第4期8卷 18-20页

作者： Kenji Ohta Kei Hirose department of earth and planetary sciences Tokyo Institute of Technology earth-Life science Institute Tokyo Institute of Technology department of earth and planetary science The University of Tokyo

The thermal conductivity of iron alloys is a key to understanding the mechanism of convection in the earth’s liquid core and its thermal history. The earth’s magnetic field is formed by a dynamo action that requires...

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The naked planet earth:Most essential pre-requisite for the origin and evolution of life

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Geoscience Frontiers 2013年第2期4卷 141-165页

作者： S.Maruyama M.Ikoma H.Genda K.Hirose T.Yokoyama M.Santosh department of earth and planetary sciences Tokyo Institute of Technology2-12-1 OokayamaMeguro-kuTokyo 152-8551Japan department of earth and planetary science.the university of tokyo 7-3-1 HongoBunkyo-kuTokyo 113-0033.Japan department of earth and planetary sciences.tokyo Institute of Technology 2-12-1 OokayamaMeguro-ku.Tokyo 152-8551Japan School of earth sciences and Resources China University of Geosciences(Beijing) Faculty of science Kochi UniversityKochi 780-8520Japan

Our blue planet earth has long been regarded to carry full of nutrients for hosting life since the birth of the *** we speculate the processes that led to the birth of early life on earth and its aftermath, finally leading to the evolution of *** evaluate：（1） the source of nutrients,（2） the chemistry of primordial ocean,（3） the initial mass of ocean,and（4） the size of *** the life-building nutrients,phosphorus and potassium play a key *** three types of rocks can serve as an adequate source of nutrients：（a） continent-forming TTG（granite）,enabling the evolution of primitive life to metazoans;（b） primordial continents carrying anorthosite with KREEP（Potassium,Rare earth Elements, and Phosphorus） basalts,which is a key to bear life;（c） carbonatite magma,enriched in radiogenic elements such as U and Th,which can cause mutation to speed up evolution and promote the birth of new species in continental rift *** second important factor is ocean *** primordial ocean was extremely acidic（pH = 1-2） and enriched in halogens（CI,F and others）,S,N and metallic elements（Cd,Cu,Zn,and others）,inhibiting the birth of *** tectonics cleaned up these elements which interfered with *** ocean finally appeared in the Phanerozoic with pH = 7 through extensive interaction with surface continental crust by weathering,erosion and transportation into *** initial ocean mass was also *** birth of life and aftermath of evolution was possible in the habitable zone with 3-5 km deep ocean which was able to supply sufficient nutrients. Without a huge landmass,nutrients cannot be supplied into the ocean only by ridge-hydrothermal circulation in the ***,the size of the planet plays a crucial *** of massive planets is less efficient than smaller ones,so that return-flow of seawater into mantle does not occur until central stars finish their main *** to the suitable size of earth,the dawn of Phaneroz

关键词： earth Life Habitable planet Initial ocean mass Metazoan Nutrients

Newly-generated Daliangshan Fault Zone—Shortcutting on the central section of Xianshuihe-Xiaojiang fault system

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science China earth sciences 2008年第9期51卷 1248-1258页

作者： IKEDA Yasutaka TOGO Masayoshi TAJIKARA Masayoshi ECHIGO Tomoo OKADA Shinsuke department of earth and planetary science University of TokyoTokyo 113-0033 Japan Hosei university Tokyo 194-0298 Japan

The Daliangshan fault zone is the eastern branch in the central section of Xianshuihe-Xiaojiang fault system. It has been neglected for a long time, partly because of no destructive earthquake records along this fault zone. On the other hand, it is located on the remote and inaccessible plateau. So far it was excluded as part of the Xianshuihe-Xiaojiang fault system. Based on the interpretation of aerophotographs and field investigations, we document this fault zone in detail, and give an estimation of strike-slip rate about 3 mm/a in Late Quaternary together with age dating data. The results suggest that the Daliangshan fault zone is a newly-generated fault zone resulted from shortcutting in the central section of Xianshuihe-Xiaojiang fault system because of the clockwise rotation of the Southeastern Tibetan Crustal Block, which is bounded by the Xianshuihe-Xiaojiang fault system. Moreover, the shortcutting may make the Daliangshan fault zone replace the Anninghe and Zemuhe fault zones gradually, and finally, the later two fault zones will probably die out with the continuous clockwise rotation.

关键词： Daliangshan fault zone newly-generated fault Xianshuihe-Xiaojiang fault system southeast Tibet

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

Endogenous/exogenous dual stimulation“ROS engineering”amplification combined with autophagy-augmented for efficient ferroptosis therapy

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Nano Research 2025年第1期18卷 597-606页

作者： Pengye Du Pengpeng Lei Yuan Liang Ran An Yi Wei Shuyu Liu Jianhao Zheng Hongjie Zhang State Key Laboratory of Rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China department of Chemistry Tsinghua UniversityBeijing 100084China

“Reactive oxygen species(ROS)engineering”is one of the most promising anti-tumor treatments developed in recent *** explosion of ROS will cause oxidative stress,thereby inducing tumor cell ***,ROS accumulation in tumor cells is eliminated by endogenous cellular self-regulation *** this work,a kind of endogenous/exogenous dual stimulation nanoagent noted as UMZC is *** reaction occurs between NH_(2)-MIL-88B(Fe)contained in UMZC and the overexpression of endogenous H_(2)O_(2)to generate ROS,amplified by endogenous H_(2)S of colon tumor *** addition,NH_(2)-MIL-88B(Fe)also functions to deplete glutathione(GSH)for stopping it from consuming *** nanoparticles at the core of UMZC convert near-infrared into visible light,which excites zinc phthalocyanine to initiate the photochemical reaction that generates more ROS,thus alleviating the lack of tissue penetration depth for visible *** agonist chitosan oligosaccharides induce enhancement of cellular autophagy for disrupting cellular metabolic stress and the resistance to oxidative stress of tumor cells,allowing“ROS engineering”to fully exert anti-tumor *** of ROS generation,GSH depletion,and induced cellular autophagy caused by nanoagents have promoting effects on the occurrence of ***,the nanoagents show the ability to effectively treat colon tumors.

关键词： reactive oxygen species(ROS)engineering upconversion nanoparticles cellular autophagy ferroptosis tumor therapy

Geographic distribution of arsenic contamination in the Himalayan Rivers flowing through Pakistan: Implications for its natural source and effects of anthropogenic activities

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International Journal of Sediment Research 2023年第4期38卷 543-555页

作者： Ishtiaque Hussain Hafiz Ur.Rehman Takaaki Itai Junaid Ali Khattak Abida Farooqi Environmental Geochemistry Laboratory Department of Environmental Sciences Faculty of Biological Sciences Quaid-i-Azam University department of Environmental sciences University of Baltistan Skardu Graduate School of sciences and Engineering Kagoshima University department of earth and planetary Environmental science (UG) Graduate School of Science The University of Tokyo department of earth and planetary Physics (UG) Graduate School of Science The University of Tokyo department of earth and planetary science (GR) Graduate School of Science The University of Tokyo

Arsenic(As) in natural hydrological systems is known as a worldwide major environmental concern. A geochemical and sedimentological study was done to ascertain the origin and geographical distribution of As in surface water and fluvial sediment collected from the floodplains/basins of the River Indus and its four major tributaries that drain through the northern Pakistan. The hydrogeochemical compositions of all five rivers were similar with calcium(Ca2+) and bicarbonate(HCO3-) being the dominating ions. The concentration of As ranged from 0.62-24.05 μg/L(average 3.7 ± 3.5 μg/L, n = 61) in river water, 2.3-23.4 mg/kg(average 5.7 ± 3.9 mg/kg) in suspended sediment, and 2.0-13 mg/kg(average4.13 ± 2.3 mg/kg) in fluvial sediment. Various approaches were used, including mineralogical, sequential extraction, geochemical, and statistical analyses to investigate the distribution, behavior, and potential sources of As in the sediment. The effect of geological factors on the distribution of As was also *** noticeable changes in the relative abundance of minerals were observed in the sediment at different locations along the river. Both mineralogical and statistical analyses showed that silicate minerals like muscovite, biotite, and chloride are the main As reservoir while oxides minerals like hematite and magnetite, which are minor components in the sediment are second largest As carrier. A geochemical baseline, using the normalization and cumulative frequency distribution curves was constructed for *** estimated mean human contribution of As was 3.4% in the Indus River, 1.9% in the Jhelum River, 13.7%in the Chenab River, 17.5% in the Ravi River and 5.4% in the Sutlej River, indicating relatively higher effects of anthropogenic activity along the Chenab River and Ravi River. The almost negligible effects of anthropogenic activities were additionally confirmed through the pollution assessment parameters estimated from the geo-enrichment, contamination factors, and ac

关键词： Arsenic Indus basin Geochemical baseline Source Contamination assessment

Subduction of the primordial crust into the deep mantle

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Geoscience Frontiers 2017年第2期8卷 347-354页

作者： Hiroki Ichikawa Steeve Gréaux Shintaro Azum Geodynamics Research Center Ehime University earth-Life science Institute Tokyo Institute of Technology department of earth and planetary sciences Faculty of ScienceUniversity of Kyushu

The primordial crust on the earth formed from the crystallization of the surface magma ocean during the ***,geological surveys have found no evidence of rocks dating back to more than 4 Ga on the earth＇s surface,suggesting the Hadean crust was lost due to some *** investigated the subduction of one of the possible candidates for the primordial crust,anorthosite and KREEP crust similar to the Moon,which is also considered to have formed from the crystallization of the magma *** to the present earth,the subduction of primordial crust by subduction erosion is expected to be an effective way of eliminating primordial crust from the *** this study,the subduction rate of the primordial crust via subduction channels is evaluated by numerical *** subduction channels are located between the subducting slab and the mantle wedge and are comprised of primordial crust materials supplied mainly by subduction *** have found that primordial anorthosite and KREEP crust of up to - 50 km thick at the earth＇s surface was able to be conveyed to the deep mantle within 0.1-2 Gy by that mechanism.

关键词： Primordial crust Anorthosite KREEP Subduction erosion Subduction channel

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng College of Materials science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Three-step modernization of the ocean:Modeling of carbon cycles and the revolution of ecological systems in the Ediacaran/Cambrian periods

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Geoscience Frontiers 2015年第1期6卷 121-136页

作者： Miyuki Tahata Yusuke Sawaki Yuichiro Ueno Manabu Nishizawa Naohiro Yoshida Toshikazu Ebisuzaki Tsuyoshi Komiya Shigenori Maruyama department of earth and planetary sciences Tokyo Institute of Technology earth-Life science Institute Tokyo Institute of Technology Precambrian Ecosystem Laboratory Japan Agency for Marine-Earth Science and Technology(JAMSTEC) department of Environmental science and Technology Tokyo Institute of Technology RIKEN 2-1 Hirosawa department of earth science and Astronomy The University of Tokyo Research Center for the Evolving earth and Planets Tokyo Institute of Technology

Important ecological changes of the earth （oxidization of the atmosphere and the ocean） increase in nutrient supply due to the break-up of the super continent （Rodinia） and the appearance of multi-cellular organisms （macroscopic algae and metazoan） took place in the Ediacaran period, priming the Cambrian explosion. The strong perturbations in carbon cycles in the ocean are recorded as excursions in carbonate and organic carbon isotope ratio （δ13Ccarb and δ13Corg） from the Ediacaran through early Cambrian periods. The Ediacaran-early Cambrian sediment records of δ13Ccarb and δ13Corg, obtained from the drill-core samples in Three Gorges in South China, are compared with the results of numerical simulation of a sim- ple one-zone model of the carbon cycle of the ocean, which has two reservoirs （i.e., dissolved organic carbon （DOC） and dissolved inorganic carbon （DIC）. The fluxes from the reservoirs are assumed to be proportional to the mass of the carbon reservoirs. We constructed a model, referred to here as the Best Fit Model （BFM）, which reproduce δ13Ccarb and δ13Corg records in the Ediacaran-early Cambrian period noted above. BFM reveals that the Shuram excursion is related to three major changes in the carbon cycle or the global ecological system of the earth：（1） an increase in the coefficient of remineralization by a factor of ca. 100, possibly corresponding to a change in the dominant metabolism from anaerobic respiration to aerobic respiration, （2） an increase of carbon fractionation index from 25‰, to 33‰, possibly corresponding to the change in the primary producer from rock-living cyanobacteria to free-living macro algae, and （3） an in- crease in the coefficient of the organic carbon burial by a factor of ca. 100, possibly corresponding to the onset of a biological pump driven by the flourishing metazoan and zooplankton. The former two changes took place at the start of the Shuram excursion, while the third occurred at the end of the Shuram excursion. The ot

关键词： Carbon cycle change Carbon isotope ratio Ediacaran to Cambrian Oxygen level Evolution of life