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Long-lived lunar volcanism sustained by precession-driven core-mantle friction

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National Science Review 2024年第2期11卷 114-123页

作者： Shuoran Yu Xiao Xiao Shengxia Gong Nicola Tosi Jun Huang Doris Breuer Long Xiao Dongdong Ni state {1. laboratory of Lunar and Planetary Sciences Macau University of Science and Technology Planetary Science Institute State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences CAS key {1. of Planetary Sciences Shanghai Astronomical Observatory Institute of Planetary research German Aerospace Centre(DLR)

Core-mantle friction induced by the precession of the Moon's spin axis is a strong heat source in the deep lunar mantle during the early phase of a satellite's evolution, but its influence on the long-term thermal evolution still remains poorly explored. Using a one-dimensional thermal evolution model, we show that core-mantle friction can sustain global-scale partial melting in the upper lunar mantle until ～3.1.Ga, thus accounting for the intense volcanic activity on the Moon before ～3.0 Ga. Besides, core-mantle friction tends to suppress the secular cooling of the lunar core and is unlikely to be an energy source for the long-lived lunar core dynamo. Our model also favours the transition of the Cassini state before the end of the lunar magma ocean phase(～4.2 Ga), which implies a decreasing lunar obliquity over time after the solidification of the lunar magma ocean. Such a trend of lunar obliquity evolution may allow volcanically released water to be buried in the lunar regolith of the polar regions. As a consequence, local water ice could be more abundant than previously thought when considering only its accumulation caused by solar wind and comet spreading.

关键词： Moon precession orbit volcanism

Melting geodynamics reveals a subduction origin for the Purang ophiolite,Tibet,China

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Acta Geochimica 2024年第4期43卷 754-773页

作者： Tao Ruan Zhong-Jie Bai Wei-Guang Zhu Shi-Ji Zheng state {1. laboratory of Ore deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The debate regarding whether the Yarlung-Zangbo ophiolite(YZO)on the south of the Qinghai-Tibet Plateau,formed in a mid-ocean ridge(MOR)or a supra-subduction zone(SSZ)setting has remained *** we present petrological,mineralogical,and geochemical data associated with modeling melting geodynamics of the mantle peridotites from the Purang ophiolite in the western segment of the Yarlung-Zangbo Suture Zone(YZSZ)to explore its tectonic *** Purang lherzolites are characterized by the protogranular texture and have abyssal-peridotite-like mineral compositions,including low Cr^(#)(20-30)and TiO_(2) contents(1.t%)in spinel,high Al_(2)O_(3)(2.9wt%-4.4wt%)and CaO(1.9wt%-3.7wt%)contents in orthopyroxene and LREE-depletion in *** of these lherzolites can be modeled by~1.%dynamic melting of the DMM source with a small fraction of melt(~0.5%)entrapped within the source,a similar melting process to typical abyssal *** Purang harzburgites are characterized by the porphyroclastic texture and exhibit highly refractory mineral compositions such as high spinel Cr^(#)(40-68),low orthopyroxene Al_(2)O_(3)(1.1.t%)*** in these harzburgites are enriched in Sr(up to 6.0 ppm)and LREE[(Ce)N=0.02-0.4],but depleted in Ti(200 ppm,on average)and HREE[(Yb)N1.%-23%hydrous melting with the supply rate of slab fluid at 0.1.-1..The lower clinopyroxene V/Sc ratios in harzburgites than those in lherzolites suggest a high oxidation stage of the melting system of harzburgites,which is consistent with a hydrous melting environment for these *** is therefore concluded that the Purang ophiolite has experienced a transformat

关键词： Melting geodynamics SSZ peridotites MOR peridotites Clinopyroxene Purang ophiolite

Nuclear volume effects in kinetic isotope fractionation:A case study of mercury oxidation by chlorine species

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Acta Geochimica 2024年第3期43卷 411-423页

作者： Chenlu Yang Yining Zhang Yun Liu research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China state {1. laboratory of Ore deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

It is well-known that the equilibrium isotope fractionation of mercury(Hg)includes classical massdependent fractionations(MDFs)and nuclear volume effect(NVE)induced mass-independent fractionations(MIFs).However,the effect of the NVE on these kinetic processes is not *** total fractionations(MDFs+NVEinduced MIFs)of several representative Hg-incorporated substances were selected and calculated with ab initio calculations in this work for both equilibrium and kinetic ***-induced MIFs were calculated with scaled contact electron densities at the nucleus through systematic evaluations of their accuracy and errors using the Gaussian09 and DIRAC1. packages(named the electron density scaling method).Additionally,the NVE-induced kinetic isotope effect(KIE)of Hg isotopes are also calculated with this method for several representative Hg oxidation reactions by chlorine *** KIEs for 202 Hg/^(1.8)Hg ranging from−2.27‰to 0.96‰are *** anomalous^(202)Hg-enriched KIEs(δ^(202)Hg/^(1.8)Hg=0.83‰,0.94‰,and 0.96‰,)caused by the NVE are observed,which are quite different from the classical view(i.e.,light isotopes react faster than the heavy ones).The electron density scaling method we developed in this study can provide an easier way to calculate the NVE-induced KIEs for heavy isotopes and serve to better understand the fractionation mechanisms of mercury isotope systems.

关键词： Nuclear volume effect Kinetic fractionation Hg isotopes Ab initio calculations

Origin of water in the Moon

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National Science Review 2024年第06期11卷 10-12页

作者： Hejiu Hui Ziyan Han Kang Shuai state {1. laboratory of mineral deposits research & Lunar and Planetary Science Institute School of Earth Sciences and Engineering Nanjing University CAS Center for Excellence in Comparative Planetology CAS key {1. of Earth and Planetary Physics Institute of Geology and Geophysics

It has been well known since the Apollo era that the Moon is relatively depleted in volatiles as a result of the Moonformation impact and the subsequent planetary differentiation. The lunar interior was believed to have been extremely dry [1.. The discovery of indigenous water (a collective term for H-bearing species OH, H2O, etc.) in various lunar materials [2–5] has driven a paradigm shift in our knowledge of water in the Moon, from a dry to a wet Moon.

关键词： LUNAR HYDROGEN TERRESTRIAL INTERIOR

Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning

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Petroleum Science 2024年第4期21卷 2407-2419页

作者： Qing-Jun Du Hao-Yu Zheng Jian Hou Yong-Ge Liu Jian-Fang Sun Dong Zhao state {1. laboratory of Deep Oil and Gas China University of Petroleum (East China) School of Petroleum Engineering China University of Petroleum (East China) laboratory for Marine {1. Resources Qingdao National Laboratory for Marine Science and Technology Petroleum Exploration and Production research Institute

Hot water flooding is an effective way to develop heavy oil reservoirs. However, local channeling channels may form, possibly leading to a low thermal utilization efficiency and high water cut in the reservoir. The pore structure heterogeneity is an important factor in forming these channels. This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are *** the experiments, computer tomography(CT) scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels. The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity. The zone where oil saturation reduction exceeds 20% is defined as a channeling *** scanning area is divided into 1.0 equally sized zones based on the CT scanning images, and threedimensional(3D) distributions of the channeling channels are developed. Four micro remaining oil distribution patterns are proposed, and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed. The results show that hot water flooding is more balanced in the weakly heterogeneous model, and the oil saturation decreases by more than 20% in most zones without narrow channeling channels forming. In the strongly heterogeneous model, hot water flooding is unbalanced, and three narrow channeling channels of different lengths form. In the weakly heterogeneous model, the oil saturation reduction is greater in zones with larger pores. The distribution range of the average pore size is larger in the strongly heterogeneous model. The network remaining oil inside the channeling channels is less than outside the channeling channels,

关键词： Heavy oil Hot water flooding Pore structure Channeling channels CT scanning

Negative Poisson’s ratio cable compensation support for 32 m super-large-span highway tunnel:A case study

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Underground Space 2024年第1期14卷 156-175页

作者： Aipeng Guo Manchao He Songyuan Liu Zhifeng Du Zengwang Lyu Zhigang Tao state {1. laboratory for Geomechanics and Deep Underground Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China Department of Civil and mineral Engineering University of TorontoToronto M5S 1A4Canada state {1. laboratory for Geomechanics and Deep Underground Engineering Sanmenxia Research CenterHenan 472099China

Although super-large-span tunnels ensure convenient transportation,they face many support *** lack of normative construction guidance and the limited number of reference engineering cases pose a significant challenge to the stability control of superlarge-span *** on the geological conditions of a super-large-span tunnel(span=32.1. m)at the bifurcation section of the Shenzhen interchange,this study determined support parameters via theoretical calculation,numerical simulation,and engineering *** support effects of negative Poisson’s ratio(NPR)anchor cables and ordinary anchor cables on super-long-span tunnels were simulated and ***,based on FLAC3D simulations,the surrounding rock stress field of NPR anchor cables was analyzed under different prestressing conditions,and the mechanism of a long-short combination,high-prestress compensation NPR anchor cable support was *** the basis of numerical simulations,to our knowledge,the three-dimensional(3D)geomechanical model test of the NPR anchor cable and ordinary anchor cable support for super-large-span tunnel excavation is conducted for the first time,revealing the stress evolution law of super-large-span tunnels,deformation and failure characteristics of the surrounding rock,and the changing trend of the anchor cable’s axial force,and verifies that NPR anchor cables with high preloads are suitable for super-large-span tunnel support and have advantages over ordinary anchor *** study can provide a reliable theoretical reference for the support design and stability control of the surrounding rock of similar shallow-buried super-large-span tunnels.

关键词： Super-large-span tunnel Negative Poisson’s ratio(NPR)anchor cable Excavation compensation method Numerical simulation Geomechanical model test

Analysis method and experimental study of ice accumulation detection signal based on Lamb waves

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Chinese Journal of Aeronautics 2024年第8期37卷 388-403页

作者： Yanxin ZHANG Hongjian ZHANG Xian YI Binrui WU Xianlei GUAN Jianjun XIONG key {1. of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China state {1. laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft *** guided waves have the unique advantage of detecting icing in a relatively large area,but quantitative identification of ice layers is a *** this paper,a quantitative identification method of ice accumulation based on ultrasonic guided waves is ***,a simulation model for the wave dynamics of piezoelectric coupling in three dimensions is established to analyze the propagation characteristics of Lamb waves in a structure consisting of an aluminum plate and an ice *** wavelet transform method is utilized to extract the Time of Flight(ToF)or Time of Delay(ToD)of S_(0)/B_(1. mode waves,which serves as a characteristic parameter to precisely determine and assess the level of ice ***,an experimental system is developed to evaluate the feasibility of Lamb waves-based icing real-time detection in the presence of spray ***,a combination of the Hampel median filter and the moving average filter is developed to analyze ToF/ToD *** simulation results reveal a positive correlation between geometric dimensions(length,width,thickness)of the ice layer and ToF/ToD of B1.mode waves,indicating their potential as indicators for quantifying ice *** results of real-time icing detection indicate that ToF/ToD will reach greater peak values with the growth of the arbitrary-shaped ice layer until saturation to effectively predict the simulation *** study lays a foundation for the practical application of quantitative icing detection via ultrasonic guided waves.

关键词： Ice Ice accumulation Ultrasonic sensor Ultrasonic guided wave Lamb wave Wavelet transform

Asperochones A and B,two antimicrobial aromatic polyketides from the endophytic fungus Aspergillus ***-2

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Chinese Chemical Letters 2024年第9期35卷 206-209页

作者： Hong Zhang Cui-Ping Li Li-Li Wang Zhuo-Da Zhou Wen-Sen Li Ling-Yi Kong Ming-Hua Yang Jiangsu key {1. of Bioactive Natural Product research and state key {1. of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

Two novel fungal metabolites,asperochones A and B,were obtained from an Aspergillus *** structures were determined by 1./2D nuclear magnetic resonance(NMR)spectroscopy,high resolution electrospray ionization mass spectroscopy(HRESIMS),and single-crystal X-ray diffraction *** A possesses an intriguing skeleton bearing 5/6/6/6/7/5/5/5 octacyclic ring system,and asperochone B also exhibits an unusual carbon skeleton with five stereochiral *** structures were proposed as heterotrimeric and heterodimeric products of aromatic *** addition,asperochone A exhibited a potential anti-tuberculosis effect since it showed a moderate potency against Mycobacterium smegmatis.

关键词： Aspergillus sp. Asperochones A and B Aromatic polyketides Heterotrimeric compound Anti-tuberculosis effect Antifibrotic activity

Monazite U-Th-Pb and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit in the Qinling orogen,central China:Implications for regional gold metallogeny

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Science China Earth Sciences 2024年第8期67卷 2478-2494页

作者： Xueling YU Jianwei LI Xiaoye JIN Shaorui ZHAO Chongguo HE Yunlong ZHU state {1. laboratory of Geological Processes and mineral Resources China University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China

The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold {1.ization and regional tectonism remain *** we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit *** Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation,with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe *** ores in the black shales have been intensively oxidized and consist mainly of hematite,goethite,gypsum,quartz,calcite,native gold,and unrecognized iron ***,gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold *** ores consist of pyrite,marcasite,sericite,and quartz,which are associated with a variety of accessory {1.s,including monazite,apatite,and *** is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite,but minor native gold grains also occur as inclusions in *** is well developed in the ores,and has close textural association with Au-bearing pyrite and *** monazite grains have zoned textures consisting of a core area(Mnz1.and an overgrowth zone(Mnz2).Mnz1.contains 4.8–1. wt.%ThO_(2)and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE *** yields common lead-corrected^(208)Pb/^(232)Th dates ranging from 91.±1. to41.±4 Ma(2σ).These dates are interpreted in terms of a detrital origin for monazite in the core ***2 has much lower ThO_(2)contents of 0.8–1.7 wt.%and shows weak negative Eu anomalies in the chondrite-normalized REE *** yields common lead-corrected^(208)Pb/^(232

关键词： Monazite U-Th-Pb dating Sericite Rb-Sr dating Late Triassic(Norian) Orogenic gold deposit Xiajiadian