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New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,China and implications on its spatio-temporal distribution and paleogeography

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Journal of Palaeogeography 2024年第2期13卷 199-211页

作者： Yun-Feng Li chang-lu zhang Fei Liang Xiao Tan Fan-Hao Gong Chun-Lin Sun Tao Li Yu-Ling Na Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026Jilin ProvinceChina College of Earth Sciences Jilin UniversityChangchun 130061Jilin ProvinceChina College of Paleontology Shenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Key Lab of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Shenyang Center of Geological Survey China Geological SurveyShenyang 110034Liaoning ProvinceChina

Coniopteris simplex is a common component in many Jurassic ***,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long ***,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner *** new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small *** on these observations,we emended the diagnosis of this common *** spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 48.9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 129.3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.

关键词： Coniopteris simplex Yan'an Formation Middle Jurassic Inner Mongolia Paleogeography

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Analyzing carbon emissions and influencing factors in Chengdu-Chongqing urban agglomeration counties

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Journal of Environmental Sciences 2025年第5期151卷 640-651页

作者： zhang Heng lu Wenfu Peng Lindan zhang Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources(Ministry of Education) Sichuan Normal UniversityChengdu 610068China The Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610068China

Majority of carbon emissions originate from fossil energy consumption,thus necessitating calculation and monitoring of carbon emissions from energy *** this study,we utilized energy consumption data from Sichuan Province and Chongqing Municipality for the years 2000 to 2019 to estimate their statistical carbon *** then employed nighttime light data to downscale and infer the spatial distribution of carbon emissions at the county level within the Chengdu-Chongqing urban ***,we analyzed the spatial pattern of carbon emissions at the county level using the coefficient of variation and spatial autocorrelation,and we used the Geographically and Temporally Weighted Regression(GTWR)model to analyze the influencing factors of carbon emissions at this *** results of this study are as follows:(1)from 2000 to 2019,the overall carbon emissions in the Chengdu-Chongqing urban agglomeration showed an increasing trend followed by a decrease,with an average annual growth rate of 4.24%.However,in recent years,it has stabilized,and 2012 was the peak year for carbon emissions in the Chengdu-Chongqing urban agglomeration;(2)carbon emissions exhibited significant spatial clustering,with high-high clustering observed in the core urban areas of Chengdu and Chongqing and low-low clustering in the southern counties of the Chengdu-Chongqing urban agglomeration;(3)factors such as GDP,population(Pop),urbanization rate(Ur),and industrialization structure(Ic)all showed a significant influence on carbon emissions;(4)the spatial heterogeneity of each influencing factor was evident.

关键词： Carbon emissions Chengdu-Chongqing urban agglomeration Spatial autocorrelation Geographically and temporally weighted regression

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In-situ liquid-phase transmission electron microscopy for two-dimensional energy materials

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Science China Chemistry 2025年第2期68卷 414-429页

作者： Junyu zhang Liangping Xiao Mi lu School of Materials Science and Engineering Xiamen University of TechnologyXiamen 361024China Instrumental Analysis Center Laboratory and Equipment Management DepartmentHuaqiao UniversityXiamen 361021China Department of Physics Research Institute for Biomimetics and Soft MatterFujian Provincial Key Laboratory for Soft Functional MaterialsJiujiang Research InstituteXiamen UniversityXiamen 361005China

Two-dimensional(2D)materials are vital for the development of advanced materials in the next-generation energy conversion and storage ***-situ liquid-phase transmission electron microscopy(LP-TEM)acts as a powerful tool for characterizing the dynamic evolution of materials under work condition in real time and in ***,this mini-review highlights the considerable advances in the utilization of in-situ LP-TEM for studying the physical and chemical process dynamics of 2D materials,such as their nucleation growth and phase *** electrocatalytic water splitting reactions and CO_(2) electroreduction of 2D energy materials are *** underlying electrochemical reaction mechanisms of the 2D electrode materials in rechargeable batteries are discussed and ***,the current challenges and perspectives for future research are *** min-review aims to inspire and stimulate further innovation and encourage the broader adoption of LP-TEM in exploring the fascinating dynamics of 2D energy materials.

关键词： two-dimensional(2D)materials liquid-phase transmission electron microscopy electrochemical reaction electrode materials

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Numerical Study of Flow and Heat Transfer Characteristics of Shell-and-Tube Molten Salt Electric Heater with Circularly Perforated Baffles

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Journal of Thermal Science 2025年第1期34卷 24-33页

作者： LIN Yongjie zhang Cancan WU Yuting zhang Yi lu Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of TechnologyBeijing 100124China

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings(φ),i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/(Δp)^(1/3)was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29%to 17.18%over the unopened-hole solution.

关键词： molten salt electric heater perforated baffles heat transfer

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Bound state noise-like pulses generation from composite filtering effects

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Optoelectronics Letters 2025年第3期21卷 142-148页

作者： chang Qingyu zhang Caishi College of Physics & Optoelectronic Engineering Jinan University Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology School of Physics and Optoelectronic EngineeringMacau University of Science and Technology School of Innovation Engineering Macau University of Science and Technology

This paper demonstrated the generation of multi-wavelength bound state noise-like pulse (BNLP) in a dispersion-managed composite-filtered fiber laser consisting of nonlinear polarization rotation (NPR) and *** the case of BNLP,the generation is caused by the interaction between two noise-like pulses (NLPs) induced by the comb-filtering effect,and bound state level can be artificially controlled in the *** work provides a new method for generating low-coherence pulses and establishes a research idea for the study of the comb-filtering effects.

关键词： A

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Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年第2期68卷 216-229页

作者： Yuxuan zhang An-An lu Xiang-Gen XIA Xiqi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

关键词： massive MIMO-OFDM cross subcarrier precoder design transform domain precoding vectors effective channel symplectic optimization

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A quantum-search-based multi-classifier for image recognition

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 17-27页

作者： lu Liu Xingyu Wu lufan zhang Chuan Wang School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China Applied Optics Beijing Area Major Laboratory Beijing Normal UniversityBeijing 100875China

The multi-class classification of images is a pivotal challenge within the realm of image *** the volume of visual data continues to expand,there is a burgeoning interest in harnessing the unique capabilities of quantum computation to augment the efficiency of classification ***,many existing methods for training quantum image multi-classifiers parallel classical machine learning techniques,where the requisite circuit measurements increase linearly with the volume of training *** work introduces a novel approach for training a quantum image multi-classifier based on the quantum search *** have meticulously conducted rigorous experiments on a handwritten digit dataset,a classic benchmark in the *** results have been meticulously compared with previous works,and the comparative analysis not only validates the efficiency of our proposed approach,requiring only O(N/b)measurements during training,but also highlights a significant quadratic speedup of the algorithm.

关键词： quantum computation image recognition quantum search algorithm

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Mechanism of extracellular electron transport and reactive oxygen mediated Sb(Ⅲ)oxidation by Klebsiella aerogenes HC10

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Journal of Environmental Sciences 2025年第1期147卷 11-21页

作者： Qun Rong Chaolan zhang Caiyuan Ling Dingtian lu Linjiang Jiang College of Resources Environment and Materials Guangxi UniversityNanning 530004China School of Environment and Life Science Nanning Normal UniversityNanning 530001China

Microbial oxidation and the mechanism of Sb(Ⅲ)are key governing elements in biogeochemical cycling.A novel Sb oxidizing bacterium,Klebsiella aerogenes HC10,was attracted early and revealed that extracellular metabolites were the main fractions driving Sb ***,linkages between the extracellular metabolite driven Sb oxidation process and mechanism remain ***,model phenolic and quinone compounds,i.e.,anthraquinone-2,6-disulfonate(AQDS)and hydroquinone(HYD),representing extracellular oxidants secreted by *** HC10,were chosen to further study the Sb(Ⅲ)oxidation mechanism.N_(2)purging and free radical quenching showed that oxygen-induced oxidation accounted for 36.78%of Sb(Ⅲ)in the metabolite reaction system,while hydroxyl free radicals(·OH)accounted for 15.52%.·OH and H_(2)O_(2)are the main driving factors for Sb *** quenching,methanol purification and electron paramagnetic resonance(EPR)analysis revealed that·OH,superoxide radical(O_(2)^(•-))and semiquinone(SQ-•)were reactive intermediates of the phenolic induced oxidation ***-induced ROS are one of the main oxidants in *** voltammetry(CV)showed that electron transfer of quinone also mediated Sb(Ⅲ)*** of Sb(V)was scavenged by the formation of the secondary Sb(V)-bearing mineral mopungite[NaSb(OH)6]in the incubation *** study demonstrates the microbial role of oxidation detoxification and mineralization of Sb and provides scientific references for the biochemical remediation of Sb-contaminated soil.

关键词： Antimonite oxidation Active oxygen Free radical Electron transfer AQDS

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Cotransport of nanoplastics with nZnO in saturated porous media:From brackish water to seawater

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Journal of Environmental Sciences 2025年第2期148卷 541-552页

作者： Yuanzhang Hou Yange Wang Yidi zhang Zhibo lu Zhenbo zhang Zhiqiang Dong Yuping Qiu Department of Environmental Science College of Environmental Science and EngineeringTongji UniversityState Key Laboratory of Pollution Control and Resources ReuseShanghai Institute of Pollution Control and Ecological SecurityShanghai 200092China School of Medicine Tongji UniversityShanghai 200065China Municipal Environmental Protection Engineering Co. Ltd of CERC Shanghai GroupShanghai 201906China China Railway Engineering Group Co. Beijing 100039China

The ocean serves as a repository for various types of artificial ***(NPs)and nano zinc oxide(nZnO),which are frequently employed in personal care products and food packaging materials,are likely simultaneously released and eventually into the ocean with surface ***,their mutual influence and shared destiny in marine environment cannot be *** study examined how nanomaterials interacted and transported through sea sand in various salinity *** showed that NPs remained dispersed in brine,while nZnO formed *** seawater of 35 practical salinity units(PSU),nZnO formed heteroaggregates with NPs,inhibiting NPs mobility and decreasing the recovered mass percentage(Meff)from 24.52%to 12.65%.In 3.5 PSU brackish water,nZnO did not significantly aggregate with NPs,and thus barely affected their ***,NPs greatly enhanced nZnO transport with Meff increasing from 14.20%to 25.08%,attributed to the carrier effect of higher mobility *** from brackishwater to seawater was simulated in salinity change experiments and revealed a critical salinity threshold of 10.4 PSU,below which the mobility of NPs was not affected by coexisting nZnO and above which nZnO strongly inhibited NP *** study highlights the importance of considering the mutual influence and shared destiny of artificial nanoparticles in the marine environment and how their interaction and cotransport are dependent on changes in seawater salinity.

关键词： Homoaggregate Heteroaggregate Transport Sea sand Salinity threshold

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Data-based neural controls for an unknown continuous-time multi-input system with integral reinforcement

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Control Theory and Technology 2025年第1期23卷 118-130页

作者： Yongfeng Lv Jun Zhao Wan zhang Huimin chang College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuanShanxi030024China College of Transportation Shandong University of Science and TechnologyQingdao266590ShandongChina School of Mathematical Sciences Shanxi UniversityTaiyuan030006ShanxiChina

Integral reinforcement learning(IRL)is an effective tool for solving optimal control problems of nonlinear systems,and it has been widely utilized in optimal controller design for solving discrete-time ***,solving the Hamilton-Jacobi-Bellman(HJB)equations for nonlinear systems requires precise and complicated ***,the research and application of IRL in continuous-time(CT)systems must be further *** develop the IRL of a CT nonlinear system,a data-based adaptive neural dynamic programming(ANDP)method is proposed to investigate the optimal control problem of uncertain CT multi-input systems such that the knowledge of the dynamics in the HJB equation is ***,the multi-input model is approximated using a neural network(NN),which can be utilized to design an integral reinforcement ***,two criterion networks and one action network are constructed based on the integral reinforcement signal.A nonzero-sum Nash equilibrium can be reached by learning the optimal strategies of the multi-input *** this scheme,the NN weights are constantly updated using an adaptive *** weight convergence and the system stability are analyzed in *** optimal control problem of a multi-input nonlinear CT system is effectively solved using the ANDP scheme,and the results are verified by a simulation study.

关键词： Adaptive dynamic programming Integral reinforcement Neural networks Heuristic dynamic programming Multi-input system

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