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Particuology 2015年第2期13卷 60-68页

作者： Gang Liu Jiaqi Li Kun yang wenxiang Tang Haidi Liu Jun yang Renliang Yue Yunfa Chen State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences

Perovskite-type La1-xCexMnO3 （x= 0-10%） catalysts were prepared by flame spray pyrolysis and their activities during the catalytic oxidation of benzene were examined over the temperature range of 100-450 ℃. The structural properties and reducibility of these materials were also characterized by X-ray diffraction （XRD）, N2 adsorption/desorption, H2 temperature-programmed reduction （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. The incorporation of Ce was found to improve the benzene oxidation activity, and the perovskite in which x was 0.1 exhibited the highest activity. Phase composition and surface elemental analyses indicated that non-stoichiometric compounds were present. The incorporation of Ce had a negligible effect on the specific surface area of the perovskites and hence this factor has little impact on the catalytic activity. Introduction of Ce^4＋ resulted in modification of the chemical states of both B-site ions and oxygen species and facilitated the reducibility of the perovskite. The surface Mn^4＋/Mn^3＋ ratio was increased as a result of Ce^4＋ substitution, while a decrease in the surface-adsorbed O/lattice O （Oads/Olatt） ratio was observed. The relationship between the surface elemental ratios and catalytic activity was established to allow a better understanding of the process by which benzene is oxidized over perovskites.

关键词： Perovskite Benzene elimination Ce substitution Flame spray pyrolysis Charge neutralization

Reclamation during oasification is conducive to the accumulation of the soil organic carbon pool in arid land

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Journal of Arid Land 2023年第3期15卷 344-358页

作者： yang Yuxin GONG Lu TANG Junhu College of Ecology and Environment Xinjiang UniversityUrumqi 830017China Key Laboratory of Oasis Ecology Ministry of EducationUrumqi 830017China Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem Ministry of EducationUrumqi 830017China

Soil organic carbon(SOC)and its stable isotope composition reflect key information about the carbon cycle in *** of carbon fractions in oasis continuous cotton-cropped fields can elucidate the SOC stability mechanism under the action of the human-land relationship during the oasification of arid land,which is critical for understanding the carbon dynamics of terrestrial ecosystems in arid lands under global climate *** this study,we investigated the Alar Reclamation Area on the northern edge of the Tarim Basin,Xinjiang Uygur Autonomous Region of China,in *** original desert and oasis farmlands with different reclamation years,including 6,10,18,and 30 a,and different soil depths(0-20,20-40,40-60 cm),we analyzed the variations in SOC,very liable carbon(C_(VL)),liable carbon(C_(L)),less liable carbon(C_(LL)),and non-liable carbon(C_(NL))using the method of spatial *** differences in the stable carbon isotope ratio(δ^(13)C)and beta(β)values reflecting the organic carbon decomposition rate were also determined during *** redundancy analysis,we derived and discussed the relationships among SOC,carbon fractions,δ^(13)C,and other soil physicochemical properties,such as the soil water content(SwC),bulk density(BD),pH,total salt(TS),total nitrogen(TN),available phosphorus(AP),and available potassium(AK).The results showed that there were significant differences in SOC and carbon fractions of oasis farmlands with different reclamation years,and the highest SOC was observed at the oasis farmland with 30-a reclamation year.C_(VL),C_(L),C_(LL),and C_(NL) showed significant changes among oasis farmlands with different reclamation years,and C_(VL) had the largest variation range(0.40-4.92 g/kg)and accounted for the largest proportion in the organic carbon *** proportion of C_(NL) in the organic carbon pool of the topsoil(0-20 cm)gradually increased.δ^(13)C varied from-25.61‰to-22.58‰,with the topsoil showing the most positive va

关键词： oasification soil organic carbon carbon fractions labile carbon δ^(13)C arid land

Au nanoring arrays as surface enhanced Raman spectroscopy substrate for chemical component study of individual atmospheric aerosol particle

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Journal of Environmental Sciences 2021年第2期33卷 11-17页

作者： Hanyun Cheng Xu Dong yang yang Yiqing Feng Tao wang Muhammad Ali Tahir Liwu Zhang Hongbo Fu Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science&EngineeringFudan UniuersityShanghai200433China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Monolayer-ordered gold nanoring arrays were prepared by ion-sputtering method and used as surface enhanced Raman spectroscopy(SERS)substrates to test the individual atmospheric aerosols *** to other methods used for testing atmospheric aerosols particles,the collection and subsequent detection in our work is performed directly on the gold nanoring SERS substrate without any treatment of the *** SERS performance can be tuned by changing the depth of the gold nanoring cavity as originating from coupling of dipolar modes at the inner and outer surfaces of the *** electric field exhibits uniform enhancement and polarization in the ordered Au nanoring substrate,which can improve the accuracy for detecting atmospheric aerosol *** with Raman mapping,the information about chemical composition of individual atmospheric aerosols particle and distribution of specific components can be presented *** results show the potential of SERS in enabling improved analysis of aerosol particle chemical composition,mixing state,and other related physicochemical properties.

关键词： Raman SERS Aerosol Nanoring Chemical component

Ancient deep roots for Mesozoic world-class gold deposits in the north China craton:An integrated genetic perspective

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Geoscience Frontiers 2020年第1期11卷 203-214页

作者： Cheng-Xue yang M.Santosh School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Department of Earth Sciences University of AdelaideAdelaideSA 5005Australia Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea

The North China Craton(NCC)hosts some of the world-class gold deposits that formed more than 2 billion years after the major orogenic cycles and *** diverse models for the genesis of these deposits remain equivocal,and mostly focused on the craton margin examples,although synchronous deposits formed in the interior *** we adopt an integrated geological and geophysical perspective to evaluate the possible factors that contributed to the formation of the major gold deposits in the *** the Archean tectonic framework of the NCC,the locations of the major gold deposits fall within or adjacent to greenstone belts or the margins of *** the Paleoproterozoic framework,they are markedly aligned along two major collisional sutures-the Trans North China Orogen and the Jiao-Liao-Ji *** the Mesozoic intrusions hosting these deposits do not carry adequate signals for the source of gold,we explore the deep roots based on available geophysical *** show that the gold deposits are preferentially distributed above zones of uplifted MOHO and shallow LAB corresponding to thinned crust and eroded sub-lithospheric mantle,and that the mineralization is located above regions of high heat flow representing mantle *** NCC was at the center of a multi-convergent regime during the Mesozoic which intensely churned the mantle and significantly en riched *** geophysical data on Moho and LAB upwarp from the centre towards east of the craton is more consistent with paleo-Pacific slab subduction from the east exerting the dominant control on lithospheric *** on these results,and together with an evaluation of the geochemical and isotopic features of the Mesozoic magmatic intrusions hosting the gold mineralization,we propose a genetic model that invokes reworking of ancient Au archives preserved in the lower crust and metasomatised upper mantle and which were generated through multiple subduction,underplating and cumulation ev

关键词： Gold metallogeny Subduction tectonics Lithospheric thinning Mantle metasomatism North China craton

Understanding the Low Predictability of the 2015/16 El Niño Event Based on a Deep Learning Model

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Advances in Atmospheric Sciences 2024年第7期41卷 1313-1325页

作者： Tingyu wANG Ping HUANG Xianke yang Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China National Space Science Center Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Space weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China

The 2015/16 El Niño event ranks among the top three of the last 100 years in terms of intensity,but most dynamical models had a relatively low prediction skill for this event before the summer ***,the attribution of this particular event can help us to understand the cause of super El Niño–Southern Oscillation events and how to forecast them *** present study applies attribute methods based on a deep learning model to study the key factors related to the formation of this event.A deep learning model is trained using historical simulations from 21 CMIP6 models to predict the Niño-3.4 *** integrated gradient method is then used to identify the key signals in the North Pacific that determine the evolution of the Niño-3.4 *** crucial signals are then masked in the initial conditions to verify their roles in the *** addition to confirming the key signals inducing the super El Niño event revealed in previous attribution studies,we identify the combined contribution of the tropical North Atlantic and the South Pacific oceans to the evolution and intensity of this event,emphasizing the crucial role of the interactions among them and the North *** approach is also applied to other El Niño events,revealing several new precursor *** study suggests that the deep learning method is useful in attributing the key factors inducing extreme tropical climate events.

关键词： ENSO attribution deep learning ENSO prediction extreme El Niño

KINETICS OF CARBON OXIDATION IN CARBON-BEARING REFRACTORIES

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中国有色金属学会会刊：英文版 1997年第2期7卷 39-43页

作者： Luo, Xingyuan Qiao, Zhiyu yang, Tianjun Univ of Science and Technology Beijing Beijing China

ＫＩＮＥＴＩＣＳＯＦＣＡＲＢＯＮＯＸＩＤＡＴＩＯＮＩＮＣＡＲＢＯＮＢＥＡＲＩＮＧＲＥＦＲＡＣＴＯＲＩＥＳ①ＬｕｏＸｉｎｇｙｕａｎ，ＱｉａｏＺｈｉｙｕ，ＹａｎｇＴｉａｎｊｕｎＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃａｌＣ... 详细信息

ＫＩＮＥＴＩＣＳＯＦＣＡＲＢＯＮＯＸＩＤＡＴＩＯＮＩＮＣＡＲＢＯＮＢＥＡＲＩＮＧＲＥＦＲＡＣＴＯＲＩＥＳ①ＬｕｏＸｉｎｇｙｕａｎ，ＱｉａｏＺｈｉｙｕ，ＹａｎｇＴｉａｎｊｕｎＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃａｌＣｈｅｍｉｓｔｒｙ，Ｕｎｉｖｅｒｓｉ...

关键词： kinetics oxidation carbon bearing refractory

Viscosity Analysis on the Boltzmann Equation

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Acta Mathematica Sinica,English Series 2012年第10期28卷 2139-2152页

作者： Min Ling ZHENG Xiao Ping yang School of Science Huzhou Teachers College School of Science Nanjing University of Science&Technology

This paper is devoted to investigating the asymptotic properties of the renormalized so- lution to the viscosity equation δtfε ＋ v · △↓xfε = Q（fε, fε）＋ ε△vfε as ε →0＋. we deduce that the renormalized solution of the viscosity equation approaches to the one of the Boltzmann equation in L^1（（0, T） × RN × R^N）. The proof is based on compactness analysis and velocity averaging theory.

关键词： Viscosity Boltzmann equation renormalized solution viscosity coemcient defect measure

On the variability of vertical eddy heat flux in the upper ocean

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Acta Oceanologica Sinica 2022年第10期41卷 94-99页

作者： Tianshi Du Peiran yang Zhao Jing Key Laboratory of Physical Oceanography and Frontiers Science Center for Deep Ocean Multispheres and Earth System Ocean University of ChinaQingdao266100China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266237China International Laboratory for High-Resolution Earth System Prediction Texas A&M UniversityCollege StationTX77843-3146USA

Ocean eddies produce strong vertical heat flux(VHF)in the upper ocean,exerting profound influences on the climate and ***,mooring array provides a standard way to estimate the eddy-induced VHF(EVHF)based on the adiabatic potential density *** from the validity of adiabatic assumption,it remains unclear to what extent the estimated EVHF at a single location within a limited time period is representative of its climatological mean *** this study,we analyzed the above issue by systematically evaluating the variability of EVHF simulated by a 1-km ocean model configured over the Kuroshio *** is found that the EVHF at a single location exhibits pronounced *** averaged over one year that is comparable to the current maintenance capacity of mooring array,the EVHF still deviates significantly from its climatological mean *** more than 49%of locations in our computational domain(31°-40°N,149°-166°E),the discrepancy between the one-year mean EVHF and its climatological mean value at the peaking depth is larger than the climatological mean *** mesoscale eddies play a dominant role in the variability of EVHF but contribute little to the climatological mean EVHF;the opposite is true for submesoscale *** findings indicate that nested mooring array allowing for isolating the effects of submesoscale eddies will be useful to obtain climatological mean EVHF.

关键词： vertical eddy heat flux submesoscale mesoscale climatological value pseudo-observation experiment

Research and development of nanocrystalline w/w-based materials: novel preparation approaches, formation mechanisms, and unprecedented excellent properties

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Frontiers of Materials Science 2023年第1期17卷 87-110页

作者： Zaoming wu Qiang Li Xiaofeng yang Institute of Materials China Academy of Engineering PhysicsMianyang 621907China

Tungsten(w)has become the most promising plasma-facing material(PFM)in fusion reactor,and w still faces performance degradation caused by low-temperature brittleness,low recrystallization temperature,neutron irradiation effects,and plasma irradiation *** modification of ww-based materials in terms of microstructure manipulation is needed,and such techniques to improve the performance of materials are the topics of hot *** have found that refining the grain can significantly improve the strength and the irradiation resistance of ww-based *** this paper,novel approaches and technique routes,including the"bottom-up"powder metallurgy method and"top-down"severe plastic deformation method,are introduced to the fabrication of nanocrystalline ww-based *** formation mechanisms of nanocrystalline ww-based materials were revealed,and the nanostructure stabilization mechanisms were *** mechanical properties of nanocrystalline ww-based materials were tested,and the irradiation behaviors and performances were *** mechanisms of their high mechanical properties and excellent irradiation-damage resistance were *** article may provide an experimental and theoretical basis for the design and development of high-performance novel nanocrystallinew/w-based materials.

关键词： nanocrystalline tungsten grain boundary secondary phase doping mechanicalproperty irradiation behavior

An adaptive energy regulation in a memristive map linearized from a circuit with two memristive channels

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Communications in Theoretical Physics 2024年第3期76卷 42-50页

作者： Feifei yang Ping Zhou Jun Ma School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China

Nonlinear circuits can show multistability when a magnetic flux-dependent memristor(MFDM) or a charge-sensitive memristor(CSM) is incorporated into a one branch circuit,which helps estimate magnetic or electric field *** this paper,two different kinds of memristors are incorporated into two branch circuits composed of a capacitor and a nonlinear resistor,thus a memristive circuit with double memristive channels is *** circuit equations are presented,and the dynamics in this oscillator with two memristive terms are ***,the memristive oscillator is converted into a memristive map by applying linear transformation on the sampled time series for the memristive *** Hamilton energy function for the memristive oscillator is obtained by using the Helmholtz theorem,and it can be mapped from the field energy of the memristive *** energy function for the dual memristive map is suggested by imposing suitable weights on the discrete energy *** dynamical behaviors of the new memristive map are investigated,and an adaptive law is proposed to regulate the firing mode in the memristive *** work will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map energy calculation.

关键词： Hamilton energy dual memristive map adaptive energy regulation