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Journal of Palaeogeography 2025年第1期14卷 203-220页

作者： Yuan-Yuan Wang Ya-Bin Zhang Song-Lin Gou Guo-Cheng Zhang Institute of Resource and Environment Henan Polytechnic University Henan international joint laboratory of Biogenic Traces and Sedimentary Minerals Henan Polytechnic University

Neoichnological characterization of modern depositional settings addresses the response of benthic animals to ecological conditions and their fluctuations, usually on a relatively short time scale. In this way, analogue models for interpretation of sedimentary strata in the geological record can be *** japonicus(De Haan, 1835), a crab, is commonly found in the Pearl River Delta front of southern China. The burrows of M. japonicus are vertical or inclined, I-, U-, Y-, J-and L-shaped tubes, and these are imaged in 7.5-cm-diameter sediment cores. The cores were studied by X-ray radiography, computed tomography, and VG Studio MAX reconstruction to obtain three-dimensional images for elaborate morphological study. This crab's burrows are analogous to the trace fossil Psilonichnus. Several environmental parameters, i.e., sediment grain size and its total organic carbon(TOC) content, and turbidity and salinity of water, have been measured. The results indicated that M. japonicus prefers to live in mesohaline water with turbidity levels of 20-170 NTU, where bioturbation is more abundant. It prefers to occur in mud and silty sand substrates, with TOC content decreasing as particle size increases. The sedimentary environment, grain size and ichnofacies of analogical trace fossils Psilonichnus are discussed which supports the interpretation that Psilonichnus is a good indicator of delta front environments.

关键词： Neoichnology Macrophthalmus japonicus Pearl River Delta front Physicochemical factor

Influence of trains meeting on the ventilation performance of equipment compartment with independent air duct in high-speed train:numerical and experimental study

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Railway Engineering Science 2025年第1期33卷 127-150页

作者： Yitong Wu Wei Zhou Xifeng Liang Xinchao Su Kewei Xu Yutao Xia Zhixin Wang Sinisa Krajnović Key laboratory of Traffic safety On Track Ministry of EducationSchool of Traffic and Transportation EngineeringCentral South UniversityChangsha 410075China joint international Research laboratory of Key Technology for Rail Traffic safety Central South UniversityChangsha 410075China Division of Fluid Dynamics Department of Mechanics and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

During the train meeting events,train equipment compartments are exposed to the worst pressure changes,potentially affecting the ventilation performance of equipment,particularly for electrical facilities equipped with independent air *** this paper,a two-step method is used for numerical computation:(1)obtaining the temporal and spatial transient node data of the flow field sections during the train-passing simulation and(2)using the data as the input data for the equipment compartment *** addition,this paper also compares the difference in equipment ventilation between the single-train and trainpassing scenarios in real vehicle *** results indicate that the primary factors influencing ventilation effectiveness are the aerodynamic compression and deceleration of airflow induced by the other train's nose,as well as the instability of the external flow field in the wake of the other *** train crossing,the air is forced into the air duct,with a maximum ratio of the airflow in-duct to the airflow out-duct reaching *** average mass flow falls below the rated mass flow for the *** to the rated air volume of converter,the maximum suppression rates obtained from testing and simulation are-24.5%and-16.8%,*** to the single-train operation,the maximum suppression rates obtained from testing and simulation are-15%and-18%,*** findings provide valuable insights into the design and operation of high-speed trains.

关键词： Train-passing event Electrical facilities Independent air duct Ventilation performance

Pyrrolic nitrogen coordinated Ni^(2+) dual-atom catalyst for boosting CO_(2) electroreduction

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Science China Chemistry 2025年第2期68卷 570-579页

作者： Zhi-Wei Chen Hong-Juan Wang Chang Liu Xiu-Li Lu Tong-Bu Lu MOE international joint laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Nitrogen-doped carbon materials have been widely used for the constructions of single-atom catalysts,while the effect of different species of doped nitrogen on the catalytic activity of CO_(2) electroreduction has rarely been *** we found that pyrrolic-N coordinated Ni2+catalysts display much higher electrocatalytic CO_(2)-to-CO activity and selectivity than the corresponding pyridinic-N coordinated low valent Ni^((0–+2))catalysts,and pyrrolic-N coordinated Ni2 dual-atoms catalyst of Ni2/N-CNTs exhibits the best electrocatalytic performance,with over 90%Faradaic efficiencies in a broad potentials from−0.6 to−1.2 V *** hydrogen electrode,as well as an outstanding CO specific current of 56.2 A/mgNi and high turnover frequency of 6.2×10^(4) h^(−1),over 7-times higher than those of pyridinic-N coordinated Ni *** results indicate the weak electron-donor nature of pyrrolic-N facilitates the generation of a reduced active site at low overpotential for boosting CO_(2) *** functional theory calculations reveal that the reaction free energy for the*COOH formation on pyrrolic-N coordinated Ni catalysts are lower than those on pyridinic-N coordinated Ni catalysts,and a H_(2)Oadsorbed Ni_(2)/N-CNTs displays the optimized reaction free energy for both*COOH formation and CO desorption,which derive the best catalytic performance.

关键词： dual-atom catalyst CO_(2) electroreduction synergistic catalysis pyrrolic-N pyridinic-N

New insight into the origin and evolution of the flora and fauna of Hainan Island,China

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Science China Earth Sciences 2025年第1期68卷 52-61页

作者： Hua ZHU Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesYunnan International Joint Laboratory of Southeast Asia Biodiversity ConservationYunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian ElephantsMengla666303China

The origin of the biota of Hainan Island,China,remains a fundamental scientific *** studies on the biota,geological tectonics,and paleomagnetism proposed that during the Eocene,Hainan Island connected Vietnam and Guangxi,and then moved to the southeast to reach its present *** review mainly discusses its biota origin from molecular phylogeny and palaeobotanical *** formation and evolution of the biological groups of Hainan Island were identified via research on their genomes,phylogeny,and molecular *** research showed that the genera and species that appeared and diverged early in their evolution(i.e.,before the Miocene)can be explained by the land connection between Hainan Island,Vietnam,and Guangxi during the *** to Southeast Asian tectonic theory,in the Middle Miocene(at about 15 million years ago),Hainan Island had moved to its present *** population and genetic divergence of species with late divergence times(after 15 Ma)can be reasonably explained by the close proximity(or land connection)between Hainan Island and the Leizhou Peninsula,enabling genetic communication between Hainan Island and the Chinese mainland,but have exceptional *** have been obtained through palaeobotanical studies,showing that in the Eocene-Oligocene period,southwest China and Hainan Island had subtropical vegetation and ***,the fossil group in southeast China(in Maoming,near present-day Hainan Island)in the Late Eocene indicated a tropical rainforest vegetation and *** suggests that in the Paleogene,Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam,rather than in its present *** floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution *** pattern can be explained by the counterclockwise rotation of Hainan Island during its movement to the southeast as prop

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong Wang Da-Lei Zhang Yu-Long Zhang Henan Key laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

Elucidating oxygen evolution and reduction mechanisms in nitrogen-doped carbon-based photocatalysts

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Chinese Chemical Letters 2025年第2期36卷 224-229页

作者： Yan Wang Jiaqi Zhang Xiaofeng Wu Sibo Wang Masakazu Anpo Yuanxing Fang State Key laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Sino-UK international joint laboratory on Photocatalysis for Clean Energy and Advanced Chemicals & Materials Fuzhou University Department of Chemistry and Materials Innovation Factory University of Liverpool

Solar-induced water oxidation reaction（WOR） for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages. WOR is also associated with important reduction reactions, such as oxygen reduction reaction（ORR）, which leads to the production of hydrogen peroxide（H2O2）. These transitions are instrumental in the emergence and evolution of life. In this study, transition metals were loaded onto nitrogen-doped carbon（NDC） prepared under the primitive Earth's atmospheric conditions. These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination. The chemical pathways initiated by the pristine and metal-loaded NDC were investigated. This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.

关键词： Chemical vapor deposition Nitrogen-doped carbon Oxygen reduction reaction Photocatalysis Water oxidation reaction

Thermoresponsive helical dendronized poly(arylacetylene)s:modulating the dynamic chirality

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Science China Chemistry 2025年

作者： Xueting Lu Lei Wang Liangxuan Ren Wen Li Afang Zhang international joint laboratory of Biomimetic&Smart Polymers School of Materials Science and EngineeringShanghai University

Helical poly(arylacetylene)s have formed an intriguing class of polymers,whose chiralities are dynamic and liable to external *** combining dendronized polymer topology with dendritic oligoethylene glycols (OEGs),we here report on synthesis of a homologous series of thermoresponsive dendronized poly(arylacetylene)s with either poly(phenyl acetylene) or poly(naphthalene acetylene) as the backbones,and investigate tunability of their helical *** polymers carry dendritic OEG pendants with either methoxyl-or ethoxyl-terminals to tune their unprecedent thermoresponsive behaviors,and at the same time,dendritic shielding plays an important role in mediating their thermal phase transition *** of these polymers is originated from the chiral alanine or phenylalanine moieties within the dendritic pendants,which can be tailored through manipulating solvation in different organic solvents or via thermal dehydration and collapse in ***,achiral additives such as linear or dendritic OEGs and benzene derivatives can act similarly as thermal dehydration to induce chirality transitions of these polymers in aqueous phase through interplay competitions between the additives and the polymers against their hydration.

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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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international Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： Chen Chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo Key laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

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Understanding excitonic behavior and electroluminescence light emitting diode application of carbon dots

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Chinese Chemical Letters 2025年第2期36卷 201-206页

作者： Yuan Liu Boyang Wang Yaxin Li Weidong Li Siyu Lu School of Chemistry and Chemical Engineering Henan University of Technology College of Chemistry Zhengzhou University College of Material Engineering Henan International Joint Laboratory of Rare Earth Composite MaterialsHenan University of Engineering

Carbon dots (CDs),due to their low cost,high stability,and high luminous efficiency,have emerged as an excellent material for the emissive layer in next-generation electroluminescent light-emitting diodes(ELEDs).However,improving the efficiency of fluorescent CDs-based ELEDs remains challenging,primarily because it is difficult to utilize triplet excitons in the electroluminescence ***,enhancing the exciton utilization efficiency of CDs during electroluminescence is *** on this,we exploited the characteristic large exciton binding energy commonly found in CDs to develop exciton-emitting *** CDs facilitate the radiative recombination of excitons during electroluminescence,thereby improving the electroluminescent *** rationally selecting precursors,we developed high quantum efficiency CDs and subsequently constructed CDs-based *** blue-light device exhibited an external quantum efficiency of over 4%.This study introduces a novel design concept for CDs,providing a new strategy for developing high-performance blue ELEDs based on CDs.

关键词： Carbon dots Controllable preparation Electroluminescence Exciton emission Light-emitting diodes

COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： Xiaoqin ZHANG Zhenni YU Li ZHAO Deng-Ping FAN Guobao XIAO Zhejiang Province Key laboratory of Intelligent Informatics for safety and Emergency Wenzhou University Nankai international Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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