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Distribution of glycerol ethers in Turpan soils:implications for use of GDGT-based proxies in hot and dry regions

Frontiers of Earth Science 2018年第4期12卷 862-876页

作者： jingjie zang Yanyan LEI Huan YANG State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeoseiencesWuhan 430074China Department of Geology and Environmental Science University of PittsburghPittsburghPA 15260USA

Proxies based on glycerol dialkyl glycerol tetraethers (GDGTs), a suite of membrane lipids occurring ubiquitously in soils, have generated increasing interest in quantitative paleo-environmental reconstruction. Hot and dry climates are likely to have occurred in the geological past; however, the limitations and applicability of these proxies to hot and dry environments are still unknown. In this study, we analyzed the GDGT distribution in the Turpan (TRP) basin of China, where the highest soil temperature can be approximately 70°C, and the mean annual precipitation (MAP) is 15.3 mm. We compared GDGT-based proxies among TRP soils, Nanyang (NY) soils, and Kunming (KM) soils; these three sites exhibit similar mean annual air temperature (MAAT) albeit contrasting temperature seasonality and MAP. Archaeal isoprenoidal GDGTs (isoGDGTs) dominate over bacterial branched GDGTs (brGDGTs) in most TRP soils; this is a characteristic GDGT distribution pattern for soils from dry regions globally. Another feature is the anomalously high GDGT-0/crenarchaeol ratio, which is generally attributed to the contribution of anaerobic methanogenic archaea by previous studies; however, these anaerobic archaea are unlikely to be highly abundant in the dry TRP soils, indicating that certain uncultured halophilic Euryarchaeota are likely to produce a significant amount of GDGT-0 that finally results in a high GDGT-0/Cren ratio. The changes in the salinity of the TRP soils appear to be an important factor affecting the MBT’5ME and the relative abundance of 6- vs. 5-methyl pentamethylated brGDGTs (IRIIa’). This is likely to introduce certain scatters in the correlations between MBT’5ME and MAAT and that between IRIIa’ and pH determined at the global scale. A comparison of the MBT’5ME-inferred temperature between TRP, NY, and KM soils does not indicate a significant bias toward summer temperature, indicating that brGDGT paleothermometers in soils could reflect the MAAT.

关键词： GDGTs Turpan soils semi-arid and arid areas salinity MBT’ 5ME

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The selection of a primary marker for the Anthropocene

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Science Bulletin 2019年第22期64卷 1643-1645页

作者： Tianli Wang Liangcheng Tan Hai Xu jingjie zang Dong Li Jianghu Lan Yongming Han Li Li State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi'an 710061China Institute of Global Environment Change Xi'an Jiaotong UniversityXi'an 710049China Open Studio for Oceanic-Continental Climate and Environment Changes Qingdao Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China

Since Homo sapiens appeared,the planet has experienced continuing environmental changes[1,2].In 2000,Crutzen and Stoermer[3]systematically analysed the global changes caused by human activity over the previous 300 years and suggested that the Holocene epoch ended in the 1750s and a new geological age,the Anthropocene,***,the Anthropocene drew a lot of attention from both scientific community and the general *** recognition and placement of the Anthropocene/Holocene boundary has been a subject of heated debates over the past two *** the 35th International Geological Congress(2016;IGC),the Anthropocene Working Group(AWG)recommended the Anthropocene to be formalised with an epoch rank,with the 1950s as its lower boundary[4].

关键词： Holocene epoch boundary

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百脉泉泉群泉水氢氧稳定同位素时空变化特征

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地球环境学报 2024年第1期15卷 69-77页

作者：王雅璇肖蓓崔步礼臧婧杰郁万鑫宗荷花鲁东大学滨海生态高等研究院烟台264025 中山大学地球科学与工程学院珠海519082 中国科学院地球环境研究所西安710061

研究泉水氢氧稳定同位素时空变化特征,探究泉水的补给来源,对水资源管理及旅游业可持续发展具有重要指导意义。以百脉泉泉群为研究区,通过分析降水及泉水中的氢氧稳定同位素特征,获取了本地大气降水线、泉水同位素时空变化特征及蒸发线... 详细信息

研究泉水氢氧稳定同位素时空变化特征,探究泉水的补给来源,对水资源管理及旅游业可持续发展具有重要指导意义。以百脉泉泉群为研究区,通过分析降水及泉水中的氢氧稳定同位素特征,获取了本地大气降水线、泉水同位素时空变化特征及蒸发线,并探究了百脉泉泉水的补给来源。结果表明:大气降水中δ2H的波动范围为-151.55‰δ18O—-4.28‰,δ18O的波动范围为-19.93‰δ18O—-0.52‰,δ2H和δ18O在时间上的分布规律相似,均呈现双峰状(“M”型),本地大气降水线(LMWL)为:δ2H=7.58×δ18O+4.17。百脉泉泉水的δ2H的波动范围为-65.23‰δ18O—-37.01‰,δ18O的波动范围为-8.99‰δ18O—-4.04‰。泉水δ2H—δ18O均落在本地大气降水线上或附近,泉水同位素蒸发线(LEL)为δ2H=5.75×δ18O-δ18O13.23,斜率(5.75)小于本地大气降水线斜率(7.58),表明泉水的补给来源主要为大气降水,且在入渗之前经历了较弱的蒸发作用。各泉泉水的补给区海拔均高于298 m,补给高程呈现百脉泉和东麻湾>墨泉和梅花泉>筛子泉和龙湾泉。且因地形、地层、岩性及降水量和持续时间等因素的制约,泉水同位素值及喷涌量的变化滞后于降水,降水至泉水喷涌时的补给周期尚需进一步结合同位素定年及水文地质条件厘定。相关研究结果将为百脉泉泉水资源合理利用及泉域旅游业的可持续发展提供借鉴。

关键词：氢氧稳定同位素本地大气降水线蒸发线补给来源百脉泉泉群

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A multiple-proxy stalagmite record reveals historical deforestation in central Shandong, northern China

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Science China Earth Sciences 2020年第11期63卷 1622-1632页

作者： Liangcheng TAN Wen LIU Tianli WANG Peng CHENG jingjie zang Xiqian WANG Le MA Dong LI Jianghu LAN R.Lawrence EDWARDS Hai CHENG Hai XU Li AI Yongli GAO Yanjun CAI State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China Open Studio for Oceanic-Continental Climate and Environment Changes Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China 801 Institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering Research Center for Environmental Protection and Remediation on Groundwater Jinan 250014China Library of Chang’an University Xi’an 710064China Department of Earth Sciences University of MinnesotaMinneapolis MN 55455USA School of Geography Nanjing Normal UniversityNanjing 210097China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China Department of Geological Sciences University of Texas at San AntonioSan Antonio TX 78249USA

Evaluating anthropogenic impacts on regional vegetation changes during historical time is not only important for a better understanding of the Anthropocene but also valuable in improving the vegetation-climate *** this study,we analyzed stable isotopes(δ^18O,δ^13C)and trace elements(Mg/Ca,Sr/Ca)of a stalagmite from Huangchao Cave in central Shandong,northern China.230Th and AMS14C dating results indicate the stalagmite deposited during 174BC and AD1810,with a hiatus between AD638 and *** similarities of theδ^18O and trace elements in the stalagmite suggest they are reliable precipitation ***δ^13C of the stalagmite,a proxy of vegetation change,was generally consistent with local precipitation and temperature variations on a centennial-scale before the 15th *** typically varied from–9.6‰to–6.3‰,indicating climate controlled C3 type vegetation during this ***,a persistent and marked increasing trend in theδ^13C record was observed since the 15th century,resulting inδ^13C values from–7.7‰to–1.6‰in the next four *** unprecedentedδ^13C change caused by vegetation deterioration cannot be explained by climate change but is fairly consistent with the dramatically increasing population and farmland in *** suggest that the increasing deforestation and reclamation in central Shandong began to affect vegetation in the mountain region of central Shandong since the 15th century and severely destroyed or even cleared the forest during the 16th–18th century.

关键词： Speleothem Stable isotopes Trace elements Deforestation Human activity 16th century

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Heterophilic Graph Neural Network Based on Spatial and Frequency Domain Adaptive Embedding Mechanism

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1701-1731页

作者： Lanze Zhang Yijun Gu jingjie Peng College of Information and Cyber Security People’s Public Security University of ChinaBeijing100038China

Graph Neural Networks(GNNs)play a significant role in tasks related to homophilic *** GNNs,based on the assumption of homophily,employ low-pass filters for neighboring nodes to achieve information aggregation and ***,in heterophilic graphs,nodes from different categories often establish connections,while nodes of the same category are located further apart in the graph *** characteristic poses challenges to traditional GNNs,leading to issues of“distant node modeling deficiency”and“failure of the homophily assumption”.In response,this paper introduces the Spatial-Frequency domain Adaptive Heterophilic Graph Neural Networks(SFA-HGNN),which integrates adaptive embedding mechanisms for both spatial and frequency domains to address the aforementioned ***,for the first problem,we propose the“Distant Spatial Embedding Module”,aiming to select and aggregate distant nodes through high-order randomwalk transition probabilities to enhance modeling *** the second issue,we design the“Proximal Frequency Domain Embedding Module”,constructing adaptive filters to separate high and low-frequency signals of nodes,and introduce frequency-domain guided attention mechanisms to fuse the relevant information,thereby reducing the noise introduced by the failure of the homophily *** deploy the SFA-HGNN on six publicly available heterophilic networks,achieving state-of-the-art results in four of ***,we elaborate on the hyperparameter selection mechanism and validate the performance of each module through experimentation,demonstrating a positive correlation between“node structural similarity”,“node attribute vector similarity”,and“node homophily”in heterophilic networks.

关键词： Heterophilic graph graph neural network graph representation learning failure of the homophily assumption

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CS-FSCL decoding algorithm of polar codes based on critical sets

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Optoelectronics Letters 2024年第7期20卷 418-423页

作者： YUAN Jianguo ZHANG Fengguo HE jingjie PANG Yu School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China1

In order to reduce the number of redundant candidate codewords generated by the fast successive cancellation list(FSCL)decoding algorithm for polar codes,a simplified FSCL decoding algorithm based on critical sets(CS-FSCL)of polar codes is *** algorithm utilizes the number of information bits belonging to the CS in the special nodes,such as Rate-1 node,repetition(REP)node and single-parity-check(SPC)node,to constrain the number of the path splitting and avoid the generation of unnecessary candidate codewords,and thus the latency and computational complexity are ***,the algorithm only flips the bits corresponding to the smaller log-likelihood ratio(LLR)values to generate the sub-maximum likelihood(sub-ML)decoding codewords and ensure the decoding *** results show that for polar codes with the code length of 1024,the code rates of 1/4,1/2 and 3/4,the proposed CS-FSCL algorithm,compared with the conventional FSCL decoding algorithm,can achieve the same decoding performance,but reduce the latency and computational complexity at different list ***,under the list size of L=8,the code rates of R=1/2 and R=1/4,the latency is reduced by 33%and 13%and the computational complexity is reduced by 55%and 50%,respectively.

关键词： algorithm FSC critical

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Evolution of the porous structure for phosphoric acid etching carbon as cathodes in Li–O_(2) batteries:Pyrolysis temperature-induced characteristics changes

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Carbon Energy 2024年第1期6卷 172-181页

作者： Feiyang Yang Ying Yao Yunkai Xu Cong Wang Meiling Wang jingjie Ren Cunzhong Zhang Feng Wu Jun Lu Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijingChina Beijing Institute of Technology Chongqing Innovation Center ChongqingChina College of Chemical and Biological Engineering Zhejiang UniversityHangzhouChina

Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains ***,we revealed the carbonization condition's effect on the morphology,surface property,and electrochemical performance of the obtained *** open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature,and its unique pore structure and surface properties enable the Li–O_(2) battery with cycling longevity(221 cycles with 99.8%Coulombic efficiency at 0.2 mA cm^(−2) and controlled discharge–charge depths of 500 mAh g^(−1))and high capacity(16,334 mAh g^(−1) at 0.02 mA cm^(−2)).This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions,paving the way for future study of energy storage devices.

关键词： biomass Li-O_(2) battery oxygen catalysts porous carbon temperature parameters

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Reconfigurable logic and in-sensor encryption operations in an asymmetrically tunable van der Waals heterostructure

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Nano Research 2024年第4期17卷 3113-3119页

作者： Fan Gong Wenjie Deng Yi Wu Fengming Liu Yihao Guo Zelin Che jingjie Li Jingzhen Li Yang Chai Yongzhe Zhang Key Laboratory of Optoelectronics Technology of Education Ministry of China Faculty of Information TechnologyBeijing University of TechnologyBeijing 100124China Key Laboratory of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Department of Applied Physics Hong Kong Polytechnic UniversityKowloonHong KongChina

Reconfigurable devices can be used to achieve multiple logic operation and intelligent optical sensing with low power consumption,which is promising candidates for new generation electronic and optoelectronic integrated ***,the versatility is still limited and need to be extended by the device architectures ***,we report an asymmetrically gate two-dimensional(2D)van der Waals heterostructure with hybrid dielectric layer SiO_(2)/hexagonal boron nitride(h-BN),which enable rich function including reconfigurable logic operation and in-sensor information encryption enabled by both volatile and non-volatile optoelectrical *** the partial gate is grounded,the non-volatile light assisted electrostatic doping endowed partially reconfigurable doping between n-type and p-type,which allow the switching of logic XOR and not implication(NIMP).When the global gate is grounded,additionally taking the optical signal as another input signal,logic AND and OR is realized by combined regulation of the light and localized gate *** on the high on/off current ratio approaching 105 and reliable&switchable logic gate,in-sensor information encryption and decryption is demonstrated by manipulating the logic ***,these results provide strong extension for current reconfigurable electronic and optoelectronic devices.

关键词： in-sensor encryption reconfigurable logic van der Waals heterostructure asymmetrical tunable architecture

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Diversity of Rogue Wave Solutions to the (1+1)-Dimensional Boussinesq Equation

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Journal of Applied Mathematics and Physics 2024年第2期12卷 458-467页

作者： Xiaoming Wang jingjie Huang College of Mathematics and Statistics Jishou University Jishou China

A periodically homoclinic solution and some rogue wave solutions of (1+1)-dimensional Boussinesq equation are obtained via the limit behavior of parameters and different polynomial functions. Besides, the mathematics reasons for different spatiotemporal structures of rogue waves are analyzed using the extreme value theory of the two-variables function. The diversity of spatiotemporal structures not only depends on the disturbance parameter u0 but also has a relationship with the other parameters c0, α, β.

关键词： Boussinesq Equation Rogue wave Periodically Homoclinic Solution Spatiotemporal Structure

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Dual-logic-in-memory implementation with orthogonal polarization of van der Waals ferroelectric heterostructure

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InfoMat 2024年第2期6卷 107-117页

作者： jingjie Niu Sumin Jeon Donggyu Kim Sungpyo Baek Hyun Ho Yoo Jie Li Ji-Sang Park Yoonmyung Lee Sungjoo Lee SKKU Advanced Institute of Nanotechnology(SAINT) Sungkyunkwan UniversitySuwonRepublic of Korea Department of Nano Science and Technology Sungkyunkwan UniversitySuwonRepublic of Korea Department of Electrical and Computer Engineering Sungkyunkwan UniversitySuwonRepublic of Korea IMEC HeverleeBelgium Department of Nano Engineering Sungkyunkwan UniversitySuwonRepublic of Korea

The rapid advancement of AI-enabled applications has resulted in an increasing need for energy-efficient computing ***-in-memory is a promising approach for processing the data stored in memory,wherein fast and efficient computations are possible owing to the parallel execution of reconfigurable logic *** this study,a dual-logic-in-memory device,which can simultaneously perform two logic operations in four states,is demonstrated using van der Waals ferroelectric field-effect transistors(vdW FeFETs).The proposed dual-logic-in-memory device,which also acts as a twobit storage device,is a single bidirectional polarization-integrated ferroelectric field-effect transistor(BPI-FeFET).It is fabricated by integrating an in-plane vdW ferroelectric semiconductor SnS and an out-of-plane vdW ferroelectric gate dielectric material—CuInP_(2)S_(6).Four reliable resistance states with excellent endurance and retention characteristics were *** two-bit storage mechanism in a BPI-FeFET was analyzed from two perspectives:carrier density and carrier injection controls,which originated from the out-of-plane polarization of the gate dielectric and in-plane polarization of the semiconductor,*** conventional multilevel FeFETs,the proposed BPIFeFET does not require additional pre-examination or erasing steps to switch from/to an intermediate polarization,enabling direct switching between the four memory *** utilize the fabricated BPI-FeFET as a dual-logic-inmemory device,two logical operations were selected(XOR and AND),and their parallel execution was *** types of logic operations could be implemented by selecting different initial states,demonstrating various types of functions required for numerous neural network *** flexibility and efficiency of the proposed dual-logic-in-memory device appear promising in the realization of next-generation low-power computing systems.

关键词： ferroelectric field-effect transistor in-plane ferroelectricity logic-in-memory out-of-plane ferroelectricity

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