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水稻碳足迹研究进展文献计量学分析

中国土壤与肥料 2024年第8期 242-250页

作者：吕聪娜王冠军赵锐刘茗柴龙行尤飞白金顺颍上县农业绿色发展推进中心安徽颍上236200 北方干旱半干旱耕地高效利用全国重点实验室中国农业科学院农业资源与农业区划研究所北京100081

稻田减排降碳是实现农业碳中和的重要研究领域,全面梳理水稻碳足迹研究脉络和领域发展前沿,为未来相关研究提供参考借鉴。采用文献计量学方法,在综合分析近30多年来(1990-2023年)水稻碳足迹研究相关文献基础上,对该领域研究历程、聚焦... 详细信息

稻田减排降碳是实现农业碳中和的重要研究领域,全面梳理水稻碳足迹研究脉络和领域发展前沿,为未来相关研究提供参考借鉴。采用文献计量学方法,在综合分析近30多年来(1990-2023年)水稻碳足迹研究相关文献基础上,对该领域研究历程、聚焦主题及发展趋势进行梳理探讨。结果表明:稻田碳足迹研究受到领域学者的广泛关注,2009年后文献数量快速增长,近10年来发文量贡献率达89.2%。领域形成明显的核心研究力量,中国、美国和印度是主要的文献发表国家,发文量占全球总量的75.9%;该研究领域发文量排名前10研究机构中有6个机构来中国,中国科学院发文量位居首位。关键词共现热点分析表明,水稻碳足迹研究呈现跨学科发展趋势,在稻田碳排放数量及过程、土壤碳固持速率及潜力、不同管理措施的固碳减排效果等方面取得较大进展,稻田碳固持、碳排放的微生物机制和水稻生产的生态、经济、资源利用等效益综合评价是该领域的研究热点。未来应逐步建立科学合理、标准统一的碳足迹评价方法体系,重点关注农户生产尺度稻田碳足迹定量评估,加强基于碳足迹研究情景分析的实证研究,为降低稻田碳足迹、实现水稻低碳绿色发展提供支撑。

关键词：水稻碳足迹文献计量低碳绿色

The reservoir characteristics and their controlling factors of the sublacustrine fan in the Paleogene Dongying Formation, Bohai Sea,China

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Journal of Palaeogeography 2024年第1期13卷 127-148页

作者： Xiao-jun Pang guan-Min wang Meng Zhao Qing-Bin wang Xue-Fang Zhang School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Tianjin Branch of China National Offshore Oil Corporation Limited Tianjin 300459China

Sublacustrine fan is an important element in continental lacustrine basins and is significant for reservoir exploration. Oil and gas resources have been found in the sublacustrine fan sandstone reservoirs of the Paleogene Dongying Formation in the Bohai Sea. In this study, the characteristics of the sublacustrine fan reservoirs and the controlling factors are studied using information from logging, cores, physical properties,casting thin sections, X-ray diffraction of clay minerals, vitrinite reflectance, rock pyrolysis, manometry data,and 3D seismic data. The sublacustrine fans of the Dongying Formation in the LD10, QHD34, and BZ21 structures show high-quality reservoirs with porosity >15 % and permeability >5 m D. The main controlling factors of the high-quality reservoirs are attributed to the favorable sedimentary facies type and negligible compaction,and cementation, substantial dissolution of K-feldspar, overpressure, and the development of faults and fractures. A high-quality sublacustrine fan reservoir model has been established to explain how these factors affected the physical properties. The favorable targets for oil and gas exploration in the Dongying Formation of Bohai Sea include undercompacted sandy debris flow reservoirs showing the dissolution of K-feldspar, and the reservoirs which are connected to the source rocks by faults. This study provides insights to establish the relationship between sedimentology, diagenesis and reservoir quality. The results of this study are significant for the exploration and development of the sublacustrine fan sandstone reservoirs in the Bohai Sea and analogous sandstone reservoirs elsewhere.

关键词： Sublacustrine fan High-quality reservoir Dissolution Overpressure Fault Bohai Sea

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing

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Journal of Magnesium and Alloys 2024年第5期12卷 2041-2056页

作者： Xiaohu guan Wen wang Ting Zhang Pai Peng Qiang Liu Peng Han Ke Qiao jun Cai Liqiang wang Kuaishe wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyNo.13 Yanta RoadXi’anShaanxi 710055China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this *** structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was ***,a quantitative relationship between the microstructure and tensile yield strength was *** results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were *** IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute *** severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO *** MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% *** refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP *** particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in *** result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate.

关键词： Friction stir processing Multi-pass Mg-Gd-Y-Zn-Zr alloy LPSO phase transformation Mechanical properties

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有限域上通过算术变换进行多项式电路优化

北京邮电大学学报 2010年第1期33卷 97-101页

作者：王冠军中国矿业大学计算机学院江苏徐州221116

针对电子设计自动化(EDA)高层次综合中功耗和面积的日益严峻挑战,进行非精确算术电路的自动综合和优化,并且基于有限域特性进行字长优化.非精确多项式电路优化基于算术变换方法,首先考虑电路的定点和浮点表示情况,给出电路在不同精度界... 详细信息

针对电子设计自动化(EDA)高层次综合中功耗和面积的日益严峻挑战,进行非精确算术电路的自动综合和优化,并且基于有限域特性进行字长优化.非精确多项式电路优化基于算术变换方法,首先考虑电路的定点和浮点表示情况,给出电路在不同精度界限下的实现,进行误差和功耗、面积的权衡;然后应用分枝定界方法求解最小代价电路,决定满足误差要求的最小字长,同时利用自动综合优化方法得到最终的优化结构.实验结果显示,舍入误差只需增加0.5%～1%,即可分别得到35%的功耗降低和20%的面积缩减.

关键词：有限域非精确算术电路算术变换误差界限

Skeletal phenotypes and molecular mechanisms in aging mice

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Zoological Research 2024年第4期45卷 724-746页

作者： Qiao guan Yuan Zhang Zhi-Kun wang Xiao-Hua Liu jun Zou Ling-Li Zhang School of Exercise and Health Shanghai University of SportShanghai 200438China College of Athletic Performance Shanghai University of SportShanghai 200438China

Aging is an inevitable physiological process,often accompanied by age-related bone loss and subsequent bone-related diseases that pose serious health *** on skeletal diseases caused by aging in humans is challenging due to lengthy study durations,difficulties in sampling,regional variability,and substantial ***,mice are preferred for such studies due to their similar motor system structure and function to humans,ease of handling and care,low cost,and short generation *** this review,we present a comprehensive overview of the characteristics,limitations,applicability,bone phenotypes,and treatment methods in naturally aging mice and prematurely aging mouse models(including SAMP6,POLG mutant,LMNA,SIRT6,ZMPSTE24,TFAM,ERCC1,WERNER,and KL/KL-deficient mice).We also summarize the molecular mechanisms of these aging mouse models,including cellular DNA damage response,senescence-related secretory phenotype,telomere shortening,oxidative stress,bone marrow mesenchymal stem cell(BMSC)abnormalities,and mitochondrial ***,this review aims to enhance our understanding of the pathogenesis of aging-related bone diseases.

关键词： Aging Premature aging Mice Bone Gene knockout

Dynamic Couplingand Cooperative Control for Multi-paralleled Doubly Fed Induction Generator Wind Farms during Symmetrical Low Voltage Ride-through in a Weak Grid

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Protection and Control of Modern Power Systems 2024年第3期9卷 112-125页

作者： Lei guan jun Yao the College of Electrical Engineering at Chongqing University ChongqingChina the State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China

In multi-fed grid-connected systems,there are complex dynamic interactions between different pieces of *** in situations of weak-grid faults,the dynamic coupling between equipment becomes more *** may cause the system to experience small-signal instability during the fault *** this paper,multi-paralleled doubly fed induction generator(DFIG)-based wind farms(WFs)are taken as an example to study the dynamic coupling within a multi-fed system during fault steady-state of symmetrical low voltage ride-through(LVRT)in a weak *** analysis reveals that the dynamic coupling between WFs will introduce a damping shift to each *** inevitably affects the system’s dynamic stability and brings the risk of small-signal instability during fault steady-state in LVRT *** the distance to fault location and fault severity will exacerbate the dynamic coupling between *** of the dynamic coupling,adjusting the control state of one WF will affect the stability of the remaining WFs in the ***,a cooperative control strategy for multi-paralleled DFIG WFs is proposed to improve dynamic stability during *** analysis and the effectiveness of the proposed control strategy are verified by modal analysis and simu-lation.

关键词： Doubly fed induction generator(DFIG) wind farms(WFs) dynamic stability low voltage ride through(LVRT) weak grid dynamic coupling

Structural Engineering of Anode Materials for Low-Temperature Lithium-Ion Batteries:Mechanisms,Strategies,and Prospects

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Nano-Micro Letters 2024年第8期16卷 169-195页

作者： guan wang Guixin wang Linfeng Fei Lina Zhao Haitao Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Institute of Process EngineeringChinese Academy of SciencesBeijing 100190People’s Republic of China School of Chemical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Energy Materials and Chemical Engineering Hefei UniversityHefei 230601People’s Republic of China School of Materials Science and Engineering Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Polymer and Catalyst Synthesis Technology of Liaoning Province School of Environmental and Chemical EngineeringShenyang University of TechnologyShenyang 110870People’s Republic of China

The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical ***,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of ***,we try to review the recent reports on the synthesis and characterizations of low-temperature anode ***,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero ***,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are ***,several commonly used low-temperature anode materials are briefly ***,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase ***,the challenges that remain to be solved in the field of low-temperature anode materials are *** review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance.

关键词： Low-temperature performance Anode materials Microstructural regulations Surface modifications

Efficient removal of Cr(VI) by polydopamine-modified lignin from aqueous solution: Batch and XAFS studies

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Water Science and Engineering 2024年第1期17卷 51-61页

作者： Xiao-jie Guo Wei-kang Fu Jing-yuan Ma Bo-jun Xi Chen wang Meng-yao guan College of Materials and Environmental Engineering Hangzhou Dianzi UniversityHangzhou 310018China College of Textile and Garment Shaoxing UniversityShaoxing 312000China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Lignocellulose has the potential to become a bio-based adsorbent due to its biodegradability and *** this study,a novel polydopamine functionalized-lignin(lignin@PDA),prepared via self-polymerization of dopamine(PDA)on lignin,was used as a bio-based adsorbent for rapid scavenging of hexavalent chromium(Cr(VI)).The morphology,functional groups,crystalline structure,and chemical composition of lignin@PDA were characterized with a scanning electron microscope-energy dispersive spectrometer,Fourier transform infrared spectroscopy,X-ray diffraction,and X-ray photoelectron *** Cr(VI)adsorption process of lignin@PDA was studied using batch experiments as a function of pH,ionic strength,adsorbent dose,and contact time at room *** adsorption rate of lignin@PDA was five times greater than that of the unmodified lignin,with a maximum adsorption capacity of 102.6 mg/g in an acidic *** adsorption of Cr(VI)on lignin@PDA fit the pseudo-secondorder equation and the Freundlich model,indicating that the adsorption process was mainly dominated by chemisorption and surface *** thermodynamic parameters showed that adsorption of Cr(VI)on lignin@PDA was an endothermic and spontaneous *** X-ray absorption fine structure results showed that sorption and reduction of Cr(VI)into Cr(II)occurred simultaneously on ***,PDA coating not only improved the reactivity of lignin but also promoted the complete reduction of Cr(VI)by *** to these results,polydopamine functionalized-lignin is a promising bio-based adsorbent for immobilization of Cr(VI)from wastewater.

关键词： Lignin Polydopamine Hexavalent chromium EXAFS Adsorption mechanism

Hadoop-based secure storage solution for big data in cloud computing environment

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Digital Communications and Networks 2024年第1期10卷 227-236页

作者： Shaopeng guan Conghui Zhang Yilin wang Wenqing Liu School of Information and Electronic Engineering Shandong Technology and Business UniversityYantai264003China

In order to address the problems of the single encryption algorithm,such as low encryption efficiency and unreliable metadata for static data storage of big data platforms in the cloud computing environment,we propose a Hadoop based big data secure storage ***,in order to disperse the NameNode service from a single server to multiple servers,we combine HDFS federation and HDFS high-availability mechanisms,and use the Zookeeper distributed coordination mechanism to coordinate each node to achieve dual-channel ***,we improve the ECC encryption algorithm for the encryption of ordinary data,and adopt a homomorphic encryption algorithm to encrypt data that needs to be *** accelerate the encryption,we adopt the dualthread encryption ***,the HDFS control module is designed to combine the encryption algorithm with the storage *** results show that the proposed solution solves the problem of a single point of failure of metadata,performs well in terms of metadata reliability,and can realize the fault tolerance of the *** improved encryption algorithm integrates the dual-channel storage mode,and the encryption storage efficiency improves by 27.6% on average.

关键词： Big data security Data encryption Hadoop Parallel encrypted storage Zookeeper