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Frontiers of Earth Science 2018年第3期12卷 600-610页

作者： Yang PU jihong jia Jicheng CAO School of Geographical Sciences Nanjing University of Information Science & Technology Nanjing 210044 China

As part of an investigation of the sources of aliphatic hydrocarbons to the sediments of alpine Lake Ximencuo, leaves of the eight dominant vascular plants were collected and their hydrocarbon contents were analyzed. A series of unsaturated aliphatic hydrocarbons were identified in the plant leaves; in particular, Festuca sp. contain a series of n-alkadienes that have rarely been reported in previous studies. The comparison of n-alkane proxies （ACL27 33, ACLT, Paq, and CPI） and δ13Corg among plant leaves, surface soils, and lake sediments suggests that organic proxies have been altered to varying degrees during the transport and burial process of organic materials. It is believed that microbial reworking and source changes have great impacts on organic proxies in the alpine lake system. In addition, the cluster analysis for plant leaves depending on n-alkane compositions and the ACLT proxy generates similar results. Accordingly, we postulate that the average chain length of plant waxes might be a potential indicator of plant classification in regions such as the Qinghai-Tibet Plateau.

关键词： plant leaves alpine lake n-alkanes n-alka-dienes Qinghai-Tibet Plateau (QTP)

Implications of stalagmite density for past climate change:An example from stalagmite growth during the last deglaciation from Wanxiang Cave,western Loess Plateau

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Chinese Science Bulletin 2010年第34期55卷 3936-3943页

作者： ZHANG DeZhong ZHANG PingZhong SANG WenCui CHENG Hai WU XiuPing YUAN Ye BAI YiJun WANG jiangLin jia jihong Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Institute of Global Environmental Change Xi'an Jiaotong University Xi'an 710049 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

The density of a stalagmite(WX42A)from Wanxiang Cave,Wudu County,Gansu Province,China,in the western margin of the Asian summer monsoon region,presents regular fluctuations in different deposition periods during the last *** long timescales,high-precision 230Th dating and high-resolution stalagmite density data indicate that the density-time series between 17644 a BP and 12758 a BP is quite similar to the stalagmite δ18O record which reflects Asian monsoon ***/weakening(lighter/heavier stalagmite δ18O values)of the Asian monsoon is accompanied by increase/decrease in stalagmite *** short timescales,decrease in stalagmite density correlates to monsoon-retreat events such as the Inter-AllerФd Cold Period(IACP),Older Dryas(OD)and Inter-BФlling Cold Period(IBCP).Generally,this kind of decrease in stalagmite density reflects precipitation decrease with weakening of the Asian monsoon,which in turn slows cave dripwater rate and decreases crystal nuclei,leading to enlargement of calcite crystals,weakened biological activity and decreased soil pCO2 which increases the abundance of impure detrital materials in ***,during the period of large amplitude reduction of precipitation and biological activity which resulted from extreme monsoon-retreat events,temperature variation would dominate fluctuation of stalagmite *** example,stalagmite density increased suddenly when temperature dropped suddenly in the north Atlantic during Heinrich event 1(H-1).This may be caused by low seepage water temperature,more dissolved calcium carbonate,compact regular crystals forming under higher supersaturation,leading to the stalagmite increased *** density fluctuation sensitively recorded stalagmite growth history and environment,demonstrating that stalagmite density can be used as a proxy for paleoclimatic research.

关键词：石笋记录记录密度黄土高原西部末次冰消期 Heinrich事件气候变化笋生长方解石晶体

Asian summer monsoon precipitation recorded by stalagmite oxygen isotopic composition in the western Loess Plateau during AD1875―2003 and its linkage with ocean-atmosphere system

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Chinese Science Bulletin 2008年第13期53卷 2041-2049页

作者： LIU JingHua ZHANG PingZhong CHENG Hai CHEN FaHu YANG XunLin ZHANG DeZhong ZHOU Jing jia jihong AN ChunLei SANG WenCui Kathleen R. JOHNSON Key Laboratory of Western China's Environmental System of Ministry of Education College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Department of Geology and Geophysics University of Minnesota Minneapolis MN 55455 USA School of Geographical Sciences Southwest University Chongqing 400715 China Department of Earth System Science University of California Irvine CA 92697 USA

Based on 5 high-precision 230Th dates and 103 stable oxygen isotope ratios (δ18O) obtained from the top 16 mm of a stalagmite collected from Wanxiang Cave,Wudu,Gansu,variation of monsoonal precipita-tion in the modern Asian Monsoon (AM) marginal zone over the past 100 years was reconstructed. Comparison of the speleothem δ18O record with instrumental precipitation data at Wudu in the past 50 years indicates a high parallelism between the two curves,suggesting that the speleothem δ18O is a good proxy for the AM strength and associated precipitation,controlled by "amount effect" of the pre-cipitation. Variation of the monsoonal precipitation during the past 100 years can be divided into three stages,increasing from AD 1875 to 1900,then decreasing from AD 1901 to 1946,and increasing again thereafter. This variation is quite similar to that of the Drought/Flooding index archived from Chinese historical documents. This speleothem-derived AM record shows a close association with the Pacific Decadal Oscillation (PDO) between AD 1875 and 1977,with higher monsoonal precipitation corre-sponding to cold PDO phase and vice versa at decadal timescale. The monsoonal precipitation varia-tion is out of phase with the PDO after AD 1977,probably resulting from the decadal climate jump in the north Pacific occurring at around AD 1976/77. These results demonstrate a strong linkage between the AM and associated precipitation and the Pacific Ocean via ocean/atmosphere interaction. This rela-tionship will aid to forecast future hydrological cycle for the AM monsoon region,and to improve forecasting potential of climatic model with observation data from cave.

关键词：石笋同位素季风降水

Lightweight multifunctional metamaterial with low-frequency vibroacoustic reduction and load-bearing performances

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Applied Mathematics and Mechanics(English Edition) 2025年第3期46卷 403-422页

作者： Qi jia Dianlong YU Donghai HAN jihong WEN National Key Laboratory of Equipment State Sensing and Smart Support College of Intelligence Science and Technology National University of Defense Technology

Metamaterials can control and manipulate acoustic/elastic waves on a subwavelength scale using cavities or additional components. However, the large cavity and weak stiffness components of traditional metamaterials may cause a conflict between vibroacoustic reduction and load-bearing capacity, and thus limit their ***, we propose a lightweight multifunctional metamaterial that can simultaneously achieve low-frequency sound insulation, broadband vibration reduction, and excellent load-bearing performance, named as vibroacoustic isolation and bearing metamaterial(VIBM). The advent of additive manufacturing technology provides a convenient and reliable method for the fabrication of VIBM samples. The results show that the compressive strength of the VIBM is as high as 9.71 MPa, which is nearly 87.81% higher than that of the conventional grid structure(CGS) under the same volume fraction. Moreover, the vibration and sound transmission are significantly reduced over a low and wide frequency range, which agrees well with the experimental data, and the reduction degree is obviously larger than that obtained by the CGS. The design strategy can effectively realize the key components of metamaterials and improve their application scenarios.

关键词： Compressive strength

广义Ⅰ型弧连通极小极大分式问题的对偶(英文)

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运筹学学报 2011年第2期15卷 1-10页

作者：贾继红李泽民东莞理工学院数学教研室广东东莞523808 重庆大学数理学院重庆400045

在Ⅰ型弧连通和广义Ⅰ型弧连通假设下,建立了极大极小分式优化问题的对偶模型,并提出了弱对偶定理、强对偶定理和严格逆对偶定理.

关键词： Ⅰ型弧连通广义Ⅰ型弧连通对偶

释放孩子心中的原始生命体——读胡雨心老师《从涂鸦开始》有感

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中国美术教育 2008年第5期 68-70页

作者：贾继红北京市北京大学附属小学

“不要忽视孩子的第一笔信手涂抹，这正是儿童绘画可喜的进步。”“即使不成为画家，儿时画画的可贵经历，将使孩子终身受益。”

关键词：孩子生命体涂鸦老师儿童绘画终身受益

Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

Understanding amorphous PrO_(x)-based N-doped carbon catalyst as an efficient electrocatalyst for oxygen reduction reaction

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Journal of Rare Earths 2025年第1期43卷 73-80,I0003页

作者： Xiao Man Ying Chang Shaohong Guo Meilin jia Jingchun jia Inner Mongolia Key Laboratory of Green Catalysis and Inner Mongolia Collaborative Innovation Center for Water Environment Safety College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHohhot010022China

The development of an e fficacious and easily prepared no nprecious metal electrocatalyst is crucial for the oxygen reduction reaction(ORR).This work used a dual template method to prepare the amorphous rare earth-based catalyst PrO_(x)-NC,and optimized the calcination temperature and *** PrO_(x)-NC-900 catalyst has high durability and activity and exhibits superior ORR performance in alkaline electrolytes with an onset potential(E_(0))of 0.96 V and a half-wave potential(E_(1/2))of 0.85 *** research results indicate that the ORR performance of rare earth oxide composite carbon catalysts can be improved by adjusting oxygen vacancies(Ov).In addition,high specific surface area,N rich defect *** oxygen vacancies,and the synergistic effect of oxygen vacancies and N-doped carbon interfacial layer play a significant part in the enhancement of *** performance of the zinc air battery assembled with PrO_(x)-NC-900 is significantly improved,and rare earth oxides and carbon frameworks originating from metal organic frameworks(MOFs)contribute to the oxygen electrocatalyst and electron transfer rate of the zinc air *** catalyst provides promising information for the development of rare earth metal oxide nanostructures as potential candidate materials for ORR in alkaline media.

关键词： Rare earths Metal-organic framework Oxygen reduction reaction Zn-air batteries

Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide

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Chinese Chemical Letters 2025年第1期36卷 201-213页

作者： Wei-jia Wang Kaihong Chen College of Biological and Chemical Engineering Zhejiang University of Science and TechnologyHangzhou 310023China The Institute of Green Chemistry and Engineering School of Chemistry and Chemical EngineeringNanjing UniversitySuzhou 215163China

Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar *** precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conversion is imperative yet quite *** critical review summarizes recent advances in porous photo-responsive polymers,including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs),and conjugated microporous polymers(CMPs),those can be rationally designed from the molecular level for visible-light-driven photocatalytic CO_(2)***,special emphasis is placed on how the well-defined active sites on these polymers can influence their properties and photocatalytic *** precise regulation and control of microenvironments and electronic properties of metal active centers are crucial for boosting catalytic efficiency and selectivity,as well as for the design of better photocatalysts for CO_(2)reduction.

关键词： Carbon dioxide reduction Photocatalysis Porous polymers Well-defined catalytic sites Molecular level

Anchoring 1T-MoS_(2)petals on N-doped reduced graphene oxide for exceptional electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 619-630页

作者： jia Zhao Haoran Lai Ming Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

The effective construction of electromagnetic(EM)wave absorption materials with thin matching thickness,broad bandwidth,and remarkable absorption is a great solution to EM pollution,which is a hot topic in current environmental *** this study,N-doped reduced graphene oxide(N-rGO)was first prepared using a facile hydrothermal ***,high-purity 1T-MoS_(2)petals were homogeneously anchored to the wrinkled surface of N-rGO to fabricate 1T-MoS_(2)@N-rGO *** numerous electric di-poles and profuse heterointerfaces in 1T-MoS_(2)@N-rGO would induced the multiple reflection and scattering of EM waves in a distinct-ive multidimensional structure formed by two-dimensional N-rGO and 1T-MoS_(2)microspheres with plentiful thin nanosheets,remarkable conduction loss derived from the migration of massive electrons in a well-constructed conductive network formed by 1T-MoS_(2)@N-rGO,and abundant polarization loss(including dipolar polarization loss and interfacial polarization loss).All of these gave the 1T-MoS_(2)@N-rGO nanocomposites superior EM wave absorption *** effective absorption bandwidth of 1T-MoS_(2)@N-rGO reached 6.48 GHz with a relatively thin matching thickness of 1.84 mm,and a minimum reflection loss of-52.24 dB was achieved at 3.84 ***,the radar scattering cross-section reduction value of 1T-MoS_(2)@N-rGO was up to 35.42 dB·m^(2) at 0°,which further verified the huge potential of our fabricated 1T-MoS_(2)@N-rGO nanocomposites in practical applications.

关键词： 1T-MoS_(2)@N-rGO nanocomposites conduction loss polarization loss ultrathin matching thickness electromagnetic wave absorption