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Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David J.Bottjer department of earth sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Late Ordovician Mass Extinction: earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Identifying flow regime in the aquifer of fractured rock system in Germi Chai Basin,Iran

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Journal of Mountain Science 2024年第2期21卷 574-589页

作者： VAEZIHIR Abdorreza SEPEHRIPOUR Ali TABARMAYEH Mehri department of earth sciences University of TabrizTabriz ***Iran

Considering the importance of fractured rock aquifers in the hydrogeologic process,this research aimed to analyze the flow regime,internal degree of karstification,and estimate storage volume in fractured rock aquifers of the Germi Chai Basin in northwest Iran,which is attributed to its active tectonics,erosion,and the lithological *** the geological setting,the hypothesis is that this basin is characterized by a high degree of karstification and diffuse or intermediate flow regime leading to variation in discharge flow *** hydrodynamic and hadrochemical analysis was conducted on 9 well distributed springs across the basin from 2019 to *** maximum flow rate in most of the springs appeared in the early wet season despite their different levels of fluctuations on the monthly discharge time *** the spring recession curve form revealed an aquifer containing multiple micro-regimes withαrecession coefficients and a degree of karstification ranging between 0.001 to 0.06 and 0.55 to 2.61,*** findings indicated a dominant diffuse and intermediate flow system resulting from the development of a high density of fractures in this *** electrical conductivity of the spring changes inversely proportional to the change in flow discharge,indicating the reasonable hydrological response of the aquifer to rainfall *** analysis revealed that the delay time of spring discharge after rainfall events mostly varies between 10 to 30 *** total dynamic storage volume of the spring for a given period(2019-2020)was estimated to be approximately 1324 million cubic meters reflecting the long-term drainage potential and high perdurability of dynamic *** the maximum and minimum ratio revealed that the springs recharging system in Germi Chai Basin comes under the slow aquifers *** finding provides valuable insight into the hydrogeological properties of fractured rock aquifers contributing to effective w

关键词： Fractured rock aquifer Hydrodynamic and hadrochemical analysis Germi Chai Basin Recession coefficient

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Structural engineering of BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures towards ultrastable and tunable photoluminescence

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Nano Research 2024年第3期17卷 1636-1645页

作者： Peng Liu Yan Xu Bohan Li Yuchi Zhang Hongzhou Lian Jun Lin department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China State Key Laboratory of Rare earth Resource Utilization Chang Chun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Construction of lead halide perovskite nanocrystals(LHP NCs)heterostructures is essential to obtain highly stable photoluminescence and expand their ***,a novel self-assembly strategy combining with a solvent-free thermal-assisted synthesis and a water-triggered reaction is developed to subsequently grow BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures at low nucleation temperature with high *** as-obtained ternary BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(X=Cl,Br,I)heterostructures exhibit remarkably enhanced panchromatic emission and ultrastable luminescence ascribing to the low-defect growth based on lattice *** white light-emitting diodes(WLEDs)have been constructed with a high correlated color temperature(CCT)of 7225 K and luminous efficiency of 74.4 lm·***^(3+)-doped BaWO_(4)/CsPbX_(3)/CsPb_(2)X_(5)(Ln^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Sm^(3+),Yb^(3+)/Er^(3+))nanocomposites are further designed with excitation-dependent photoluminescence and thermochromic properties,making them excellent candidates for high-level anti-counterfeiting and *** work offers a green and universal approach in assembling CsPbX_(3)(X=Cl,Br,I)on lattice-matched tungstate with adjustable panchromatic emission for versatile optical applications.

关键词： inorganic lead halide perovskites solvent-free synthesis panchromatic emission anti-counterfeiting and encryption application

Circum-Indian Holocene sea-level database:A repository of distinct relative sea-level plots across the Indian Peninsula

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Journal of Palaeogeography 2024年第1期13卷 1-17页

作者： Shradha Menon Pankaj Khanna Santanu Banerjee REEFS Lab Department of Earth SciencesIIT GandhinagarPalajGandhinagarGujarat382355India department of earth sciences IIT BombayPowaiMumbai400076India

The Indian Peninsula is one of the most well-studied regions for Holocene sea-level fluctuations in the world, however, standardized relative sea-level datasets are missing. This study provides an archive of sealevel indicators(n = 162, 20 locations) along the western and the eastern sides of the peninsula, that have been used to develop Relative Sea Level(RSL) plots. Each dated sea-level indicator is recalibrated for its elevation based on tidal and tectonic correction, as well as age with reservoir correction, and have been separated into six zones based on coastal geomorphology and number of datasets. The database spans throughout the Holocene and covers sea-level depth/elevations from-45 m to +5 m from mean sea-level(MSL). Approximately 90 % of the dataset range from 8 ka to the present day. The first transgression is highly variable and identified between 8.5-8 ka BP in Gujarat(Zone 1), ~ 5.5 ka BP in Maharashtra(Zone 2), between 8 and 7 ka BP in Tamil Nadu(Zone 4) and between 8 and 7.5 ka BP in the Bengal coasts(Zone 6). No transgression above present sea-level is observed along Andhra Pradesh(Zone 5)(no data for Kerala-Zone 3).Further, Zones 1, 2, 4 and 6 show a strong uplift component(tectonic), whereas Zone 5 exhibits subsidence during the Holocene(Zone 3-insufficient data). Based on these findings, and given the region's coastal topography and tidal components, Zones 6 and 1 will likely undergo the largest coastal inundation, followed by Zones 5, 4, 2, and 3. These insights are critical in planning future coastal inundation measures across the Indian Peninsula.

关键词： Indian ocean Terraces Relative sea level curve Holocene Arabian sea Bay of Bengal

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Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region

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Journal of Mountain Science 2024年第6期21卷 1916-1929页

作者： Zohra LADJEL Farid ZAHRI Riheb HADJI Younes HAMED Karim ZIGHMI Kaddour BENMARCE department of earth sciences Institute of Architecture and Earth SciencesFerhat Abbas UniversitySetif 19137Algeria Unit of Emerging Materials Research Ferhat Abbes UniversitySétif 19137Algeria Laboratory of applied Research in Engineering Geology GeotechnicsWater Sciencesand EnvironmentFerhat Abbas UniversitySetif 19137Algeria International Association of Water Resources in the Southern Mediterranean Basin Gafsa 2112Tunisia department of earth sciences Faculty of SciencesUniversity of GafsaGafsa 2112Tunisia

Rock fall accidents in mountainous cliff areas have significant consequences for human life and *** study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall *** employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall *** using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling *** kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure *** 3D trajectory simulations demonstrated that the falling blocks followed the stream *** then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall *** findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards.

关键词： Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff

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Influence of upstream solar wind on magnetic field distribution in the Martian nightside ionosphere

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earth and Planetary Physics 2024年第5期8卷 728-741页

作者： JiaWei Gao ZhaoJin Rong Qi Zhang Anna Mittelholz Chi Zhang Yong Wei Key Laboratory of earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences College of earth and Planetary sciences University of Chinese Academy of Sciences Swedish Institute of Space Physics department of earth sciences Center for Space Physics and department of Astronomy Boston University

Using over eight years of Mars Atmosphere and Volatile Evolutio N （MAVEN） data,from November 2014 to May 2023,we have investigated the Martian nightside ionospheric magnetic field distribution under the influence of upstream solar wind drivers,including the interplanetary magnetic field intensity (∣BIMF∣),solar wind dynamic pressure （PSW）,solar extreme ultraviolet flux （EUV）,and Martian seasons （Ls）.Our analysis reveals pronounced correlations between magnetic field residuals and both∣BIMF∣and *** observed with EUV flux and Lswere weaker—notably,magnetic field residuals increased during periods of high EUV flux and at Mars *** find that the IMF penetrates to an altitude of 200 km under a wide range of upstream conditions,penetrating notably deeper under high∣BIMF∣*** analysis also indicates that EUV flux and IMF cone angle have minimal impact on IMF penetration *** findings provide useful constraints on the dynamic nature of Martian atmospheric escape processes and their evolution,suggesting that historical solar wind conditions may have facilitated deeper IMF penetration and higher rates of ionospheric escape than are observed ***,by establishing criteria for magnetic‘quiet’conditions,this study offers new insights into the planet’s magnetic environment under varying solar wind influences,knowledge that should help refine models of the Martian crustal magnetic field.

关键词： Martian magnetic field external magnetic field upstream solar wind drivers IMF penetration altitude magnetic field activity indices

Differentially-grown cobalt regulators cooperatively involved in the tandem catalysis for high-yield production of second amines

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Nano Research 2024年第4期17卷 2444-2450页

作者： Jinhui Xu Xiao Wang Ying Wang Fei Wang Lingling Zhang Wenjie Cui Shuyan Song 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

One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall *** promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem *** this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance *** comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are ***,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline ***,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring *** from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).

关键词： tandem catalysis CeO_(2) hierarchical structure heterogeneous catalyst dual-site materials

Valence-tailored copper-based nanoparticles for enhanced chemodynamic therapy through prolonged ROS generation and potentiated GSH depletion

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Nano Research 2024年第7期17卷 6342-6352页

作者： Xinyang Li Binbin Ding Jing Li Di Han Hao Chen Jia Tan Qi Meng Pan Zheng Ping’an Ma Jun Lin 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

Chemodynamic therapy(CDT),an inventive approach to cancer treatment,exploits innate chemical processes to trigger cell death through the generation of reactive oxygen species(ROS).While offering advantages over conventional treatments,the optimization of CDT efficacy presents challenges stemming from suboptimal catalytic efficiency and the counteractive ROS scavenging effect of intracellular glutathione(GSH).In this study,we aim to address this dual challenge by delving into the role of copper valence states in *** the unique attributes of copper-based nanoparticles,especially zero-valent copper nanoparticles(CuPd NPs),we aim to enhance the therapeutic potential of *** experiments reveal that zero-valent CuPd NPs outperform divalent copper nanoparticles(Ox-CuPd NPs)by displaying superior catalytic performance and sustaining ROS generation through a dual approach integrating peroxidase-like(POD-like)activity and Cu+***,zero-valent NPs exhibit enhanced GSH depletion compared to their divalent counterparts,thereby intensifying CDT and inducing ferroptosis,ultimately resulting in high-efficiency tumor growth *** findings reveal the impact of valences on CDT,providing novel insights for the optimization and design of CDT agents.

关键词： CuPd nanoparticle ferroptosis chemodynamic therapy valance tailoring tumor therapy