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Rebuilding the theory of isotope fractionation for evaporation of silicate melts under vacuum condition

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Acta Geochimica 2024年第4期43卷 661-676页

作者： Jie wang yun Liu Research Center for Planetary Science College of Earth and Planetary SciencesChengdu University of TechnologyChengdu 610059China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China CAS Center for Excellence in Comparative Planetology Hefei 230026China

Isotope eff ects are pivotal in understanding silicate melt evaporation and planetary accretion *** on the Hertz-Knudsen equation,the current theory often fails to predict observed isotope fractionations of laboratory experiments due to its oversimplified ***,we point out that the Hertz-Knudsen-equation-based theory is incomplete for silicate melt evaporation cases and can only be used for situations where the vaporized species is identical to the one in the *** propose a new model designed for silicate melt evaporation under *** model considers multiple steps including mass transfer,chemical reaction,and *** derivations reveal a kinetic isotopic fractionation factor(KIFF orα)αour model=[m(^(1)species)/m(^(2)species)]^(0.5),where m(species)is the mass of the reactant of reaction/nucleation-limiting step or species of diffusion-limiting step and superscript 1 and 2 represent light and heavy isotopes,*** model can eff ectively reproduce most reported KIFFs of laboratory experiments for various elements,i.e.,Mg,Si,K,Rb,Fe,Ca,and ***,the KIFF-mixing model referring that an overall rate of evaporation can be determined by two steps jointly can account for the eff ects of low P_(H2)pressure,composition,and *** addition,we find that chemical reactions,diffusion,and nucleation can control the overall rate of evaporation of silicate melts by using the fitting slope in ln(−ln f)versus ln(t).Notably,our model allows for the theoretical calculations of parameters like activation energy(E_(a)),providing a novel approach to studying compositional and environmental eff ects on evaporation processes,and shedding light on the formation and evolution of the proto-solar and Earth-Moon systems.

关键词： Evaporation Kinetic isotopic fractionation Chemical kinetics Hertz-Knudsen equation CAIS

Spin wave resonance frequency in bilayer ferromagnetic films with the biquadratic exchange interaction

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Chinese Physics B 2024年第9期33卷 607-613页

作者： Xiaojie Zhang Yuting wang Yanqiu chang Huan wang Jianhong Rong Guohong yun Inner Mongolia Key Laboratory of Nanoscience and Nanotechnology and School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China College of Science Inner Mongolia Agricultural UniversityHohhot 010018China College of Physics and Electronic Information Inner Mongolia Normal UniversityHohhot 010022China

The dependences of spin wave resonance(SWR)frequency on the surface anisotropy field,interface exchange coupling,symmetry,biquadratic exchange(BQE)interaction,film thickness,and the external magnetic field in bilayer ferromagnetic films are theoretically analyzed by employing the linear spin wave approximation and Green’s function method.A remarkable increase of SWR frequency,except for energetically lower two modes,can be obtained in our model that takes the BQE interaction into ***,the effect of the external magnetic field on SWR frequency can be increased by increasing the biquadratic to interlayer exchange *** has been identified that the BQE interaction is of utmost importance in improving the SWR frequency of the bilayer ferromagnetic *** addition,for bilayer ferromagnetic films,the frequency gap between the energetically highest mode and lowest mode is found to increase by increasing the biquadratic to interlayer exchange ratio and film thickness and destroying the symmetry of the *** results can be used to improve the understanding of magnetic properties in bilayer ferromagnetic films and thus may have prominent implications for future magnetic devices.

关键词： spin wave resonance frequency biquadratic exchange interaction interface exchange coupling surface anisotropy

Uncommon Bis-quinolizidine Alkaloids from the Hainan Sponge Neopetrosia chaliniformis

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Chinese Journal of Chemistry 2021年第7期39卷 1838-1842页

作者： Bao Chen Xia-Juan Huan Ze-Hong Miao Nicole J.de Voogd Yu-Cheng Gu chang-yun wang Yue-Wei Guo Xu-Wen Li Key Laboratory of Marine Drugs The Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdaoShandong266003 China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zu Chong Zhi RoadZhangjiang Hi-Tech ParkShanghai201203 China Open Studio for Druggability Research of Marine Natural Products Pilot National Laboratory for Marine Science and Technology(Qingdao)1 Wenhai RoadAoshanweiJimoQingdaoShandong266237 China Syngenta Jealott's Hill International Research CentreBracknellBerkshireRG426EY United Kingdom Naturalis Biodiversity Center P.O.Box 95172300 RALeidenthe Netherlands Leiden University Institute of Environmental SciencesP.O.Box 95182300 RALeidenthe Netherlands

Main observation and conclusion Two new bis-quinolizidine alkaloids,neopetrosiasins A(1)and B(2),possessing cis-and trans-quinolizidine nuclei,one known related analogue petrosin(3)and three known xestospongins(4-6),w... 详细信息

关键词： Sponge 1 Neopetrosia chaliniformis Alkaloids Configuration determination Cytotoxicity

Millimeter-wave PA design techniques in ISSCC 2024

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Journal of Semiconductors 2024年第4期45卷 16-18页

作者： yun wang Hongtao Xu State Key Laboratory of Integrated Chips and Systems School of MicroelectronicsFudan UniversityShanghai 201203China

Millimeter-wave systems with high integration level have been rapidly developed to enable modern wireless communication,sensing,and *** millimeter-wave power amplifier(PA)is one of the most challenging and critical components in a millimeter-wave transceiver,it is the last active stage in a transmitter amplifying spectrally efficient complex modulation signal for radiation with high output power.

关键词： millimeter Millimeter ISSCC

Myeloperoxidase: a new target for the treatment of stroke?

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Neural Regeneration Research 2022年第8期17卷 1711-1716页

作者： yun-chang wang Yu-Bao Lu Xiao-Lan Huang Yong-Feng Lao Lu Zhang Jun Yang Mei Shi Hai-Long Ma Ya-Wen Pan Yi-Nian Zhang The Second Clinical Medical School Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Lanzhou University Second HospitalLanzhouGansu ProvinceChina Xiangya Hospital Central South UniversityChangshaHunan ProvinceChina Department of Spine Surgery The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina University of Chinese Academy of Sciences BeijingChina

Myeloperoxidase is an important inflammatory factor in the myeloid system,primarily expressed in neutrophils and *** and its active products participate in the occurrence and development of hemorrhagic and ischemic stroke,including damage to the blood-brain barrier and *** a specific inflammatory marker,myeloperoxidase can be used in the evaluation of vascular disease occurrence and development in stroke,and a large amount of experimental and clinical data has indicated that the inhibition or lack of myeloperoxidase has positive impacts on stroke *** studies have also shown that there is a correlation between the overexpression of myeloperoxidase and the risk of *** occurrence of stroke not only refers to the first occurrence but also includes ***,myeloperoxidase is significant for the clinical evaluation and prognosis of *** paper reviews the potential role played by myeloperoxidase in the development of vascular injury and secondary brain injury after stroke and explores the effects of inhibiting myeloperoxidase on stroke *** paper also analyzes the significance of myeloperoxidase etiology in the occurrence and development of stroke and discusses whether myeloperoxidase can be used as a target for the treatment and prediction of stroke.

关键词： blood-brain barrier hemorrhagic stroke inflammation ischemic stroke microglia myeloperoxidase neutrophils secondary brain injury stroke

Gria:an efficient deterministic concurrency control protocol

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Frontiers of Computer Science 2024年第4期18卷 25-37页

作者： Xinyuan wang yun PENG Hejiao HUANG School of Computer Science and Technology Harbin Institute of TechnologyShenzhen 518055China Institute of Artificial Intelligence and Blockchain Guangzhou UniversityGuangzhou 510006China

Deterministic databases are able to reduce coordination costs in a *** property has fostered a significant interest in the design of efficient deterministic concurrency control ***,the state-of-the-art deterministic concurrency control protocol Aria has three ***,it is impractical to configure a suitable batch size when the read-write set is ***,Aria running in low-concurrency scenarios,e.g.,a single-thread scenario,suffers from the same conflicts as running in high-concurrency ***,the single-version schema brings write-after-write *** address these issues,we propose Gria,an efficient deterministic concurrency control *** has the following ***,the batch size of Gria is ***,Gria’s conflict probability in low-concurrency scenarios is lower than that in high-concurrency ***,Gria has no write-after-write conflicts by adopting a multi-version *** further reduce conflicts,we propose two optimizations:a reordering mechanism as well as a rechecking *** evaluation result on two popular benchmarks shows that Gria outperforms Aria by 13x.

关键词： deterministic concurrency control transaction processing

Mechanisms of fracture propagation from multi-cluster using a phase field based HMD coupling model in fractured reservoir

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Petroleum Science 2024年第3期21卷 1829-1851页

作者： yun-Jin wang Bo wang Hang Su Tu chang Ren-Cheng Dong Li-Zhe Li Wei-Yu Tang Ting-Xue Jiang Fu-Jian Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBejing2249China China University of Petroleum-Beijing at Karamay Karamay834000XinjiangChina China National Oil and Gas Exploration and Development Corporation Ltd. Beijing100034China University of Texas at Austin United States SINOPEC Research Institute of Petroleum Engineering Beijing100101China

Natural fractures(NFs)are common in shale and tight reservoirs,where staged multi-cluster fracturing of horizontal wells is a prevalent technique for reservoir *** NFs and stress interference are recognized as significant factors affecting hydraulic fracture(HF)propagation,the combined influence of these factors remains poorly *** address this knowledge gap,a novel coupled hydromechanical-damage(HMD)model based on the phase field method is developed to investigate the propagation of multi-cluster HFs in fractured *** comprehensive energy functional and control functions are established,while incorporating dynamic fluid distribution between multiple perforation clusters and refined changes in rock mechanical parameters during hydraulic *** HMD coupled multi-cluster HF propagation model investigates various scenarios,including single HF and single NF,reservoir heterogeneity,single HF and NF clusters,and multi-cluster HFs with NF *** results show that the HMD coupling model can accurately capture the impact of approach angle(θ),stress difference and cementation strength on the interaction of HF and *** criterion of the open and cross zones is not *** NF angle(a)is not a decisive parameter to discriminate the *** to the relationship between approach angle(θ)and NF angle(a),the contact relationship of HF can be divided into three categories(θ=a,θa).The connected NF can increase the complexity of HF by inducing it to form branch fracture,resulting in a fractal dimension of HF as high as2.1280 at angles of±45°.Inter-fracture interference from the heel to the toe of HF shows the phenomenon of no,strong and weak ***,under the influence of NFs,distant HFs from the injection can become dominant ***,as a gradually increases,inter-fracture stress interference becomes the primary factor influencing HF propagation,gradually superseding the dominance of NF

关键词： HMD coupling Phase field Natural fracture Flow distribution Hydraulic fracturing Inter-fracture interference

Resonance Analysis in a High-Rise Building: Combined Translational and Rotational Measurements

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Journal of Earth Science 2024年第3期35卷 1069-1074页

作者： Linpeng Qin yun wang chang Chen Yongxiang Wei Chunqi Liao Yi Zhang Chao wang Wentao Wan Quanyang Shao School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Fujian Earthquake Agency Fuzhou 350003China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China

0 INTRODUCTION Resonance frequency is an important indicator for structure health monitoring,which can be exacerbated by various natural forces,such as rainfall,earthquakes,and hurricanes(Wu et al.,2021;Shan et al.,2020;Gentile et al.,2016;Moser and Moaveni,2011).Clinton et al.(2006)found that changes in environmental factors could significantly affect the resonance frequency of the Millikan Library;and that compared with temperature,humidity and strong wind have greater impacts on resonance ***,some studies have confirmed the effects of environmental factors through mathematical statistical analyses,including Xia et al.(2006),Yuen and Kuok(2010),and Guéguen et al.(2017).Other studies(e.g.,Astorga et al.,2018)revealed a building’s self-healing ability,where the building’s resonance frequency drifts due to earthquake events,environmental factors,or random forced vibrations could gradually return to its original level,but the recovery time of frequency drift could be considerably different with respect to different environmental factors.

关键词： humidity rainfall earthquake

Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang Liu chang-jun wang chang Liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property