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Regulating the intrinsic electronic structure of carbon nanofibers with high-spin state Ni for sodium storage with high-power density

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Journal of Materials Science & Technology 2024年第4期171卷 16-23页

作者： Zhijia zhang Gang Xie Yuefang Chen Yanhao Wei mengmeng zhang Shulei Chou Yunxiao Wang Yifang zhang Yong Jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia

Carbon nanofibers(CNFs)with high specific surface area show great potential for sodium storage as a hard carbon ***,CNFs anchored with Ni nanoparticles(CNFs/Ni)were prepared through chemical vapor deposition and impregnation reduction methods,in situ growing on the three-dimensional porous copper current collector(3DP-Cu).The coupling effect of high-spin state Ni nanopar-ticles leads to the increase of defect density and the expansion of lattice spacing of ***,the 3DP-Cu ensures a high loading capacity of CNFs and short ion/electron transport *** an integral binder-free anode,the 3DP-Cu/CNFs/Ni exhibits excellent electrochemical performance,which demon-strates a high specific capacity with 298.5 mAh g^(-1)at 1000 mA g^(-1)after 1500 cycles,and a high power density with 200 mAh g^(-1)over 1000 cycles at 5000 mA g^(-1).Density functional theory calculation re-sults show that the high-spin state Ni regulates the electronic structure of CNFs,which significantly reduces the adsorption energy for Na^(+)(-2.7 Ev)and thus enables high-rate *** regulation of the electronic structure of carbon materials by high-spin state metal provides a new strategy for developing high-power carbonaceous anode materials for sodium-ion batteries.

关键词： Carbon nanofibers Ni nanoparticles High-spin state Sodium-ion batteries Anode materials Density functional theory calculation

Epitaxial growth of Cu_(2-x)Se on Cu(220)crystal plane as high property anode for sodium storage

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Chinese Chemical Letters 2024年第7期35卷 519-523页

作者： Zhijia zhang Shihao Sun Yuefang Chen Yanhao Wei mengmeng zhang Chunsheng Li Yan Sun Shaofei zhang Yong Jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and TechnologySuzhou 215009China Hebei Key Laboratory of Flexible Functional Materials/Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang 050018China

Three-dimentional(3D)transition metal selenides with sufficient channels could produce significant superiority on enhancing reaction kinetics for sodium-ion ***,the thorough exploration of 3D architecture with a facile strategy is still *** we report that a polycrystalline Cu_(2-x)Se film was epitaxial grown on(220)facets-exposed Cu by direct selenization of a nanoporous Cu skeleton,which is obtained by dealloying rolled Cu Mn@Cu alloy *** functional theory calculation result shows strong adsorption energy for Se atoms on Cu(220)planes during selenization reaction,rendering a low energy *** virtue of this core-shell 3D nanoporous architecture to offer abundant active sites and endow fast electron/ion transportation,the nanoporous Cu_(2-x)Se@Cu-0.15 composite electrode exhibits remarkable sodium-ion storage properties with high reversible capacity of 950.6μAh/cm^(2)at 50μA/cm^(2),suprior rate capability of 457.6μAh/cm^(2)at 500μA/cm^(2),as well as an ultra-long stability at a high current *** investigation reveals that the electrochemical reaction is a typical conversion-type reaction with different *** novel electrode synthetic strategy provides useful instructions to design the high-performance anode material for sodium-ion batteries.

关键词： Cu_(2)se 3D architecture Anode materials Density functional theory calculation Sodium-ion battery

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Dammarane-type triterpenoids from Gynostemma longipes and their protective activities on hypoxia-induced injury in PC12 cells

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Chinese Journal of Natural Medicines 2024年第5期22卷 466-480页

作者： LIANG Haizhen CHEN Xiaojuan LI Qi zhang mengmeng LU Pengxin zhang Jie SONG Juan zhang Tao GUO Baolin MA Baiping Department of Pharmaceutical Sciences Beijing Institute of Radiation MedicineBeijing 100850China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China AnKang Chia Tai Pharmaceutical Co. Ltd.Shaanxi 725000China

Sixteen new dammarane-type triterpenoid saponins(1-16)featuring diverse structural variations in the side chain at C-17,along with twenty-one known analogues(17-37),have been isolated from the rhizomes of Gynostemma longipes ***,a plant renowned for its medicinal and edible *** structural elucidation of these compounds was accomplished through comprehensive analyses of 1D and 2D NMR and HRMS spectroscopic data,supplemented by comparison with previously reported *** assays on the isolates for their protective effects against hypoxia-induced damage in pheochromocytoma cells(PC12 cells)revealed that nine saponins exhibited significant anti-hypoxic *** investigation into the anti-hypoxia mechanisms of the representative saponins demonstrated that compounds 22 and 36 markedly reduced the levels of hypoxia-induced ***,these compounds were found to decrease the release of lactate dehydrogenase(LDH)and malondialdehyde(MDA),while increasing the activity of superoxide dismutase(SOD),thereby indicating that the saponins could mitigate hypoxia-induced injuries by ameliorating apoptosis and oxidative *** findings offer substantial evidence for the future utilization and development of ***,identifying dammarane-type triterpenoid saponins as its active anti-hypoxic constituents.

关键词： Gynostemma longipes Dammarane-type saponins Anti-hypoxia effect Apoptosis

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Relationship between environmental evolution and human activities in the northeastern Qinghai-Xizang Plateau throughout the past millennium and its implications for the onset of the Anthropocene

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Science China Earth Sciences 2024年第11期67卷 3536-3549页

作者： Yang PU Xueqiong WEI Jianbao LIU Ke zhang Beibei LI Zhudeng WEI mengmeng zhang Tong HE Yanjun WANG Xiaohua SHAO School of Geographical Sciences Nanjing University of Information Science and Technology Key Laboratory of Alpine Ecology Institute of Tibetan Plateau Research Chinese Academy of Sciences State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

In current research on the Anthropocene, assessing the impact of human activities via stratigraphic records of sediments and demarcating the Anthropocene epoch globally are critical scientific issues that urgently need to be addressed. The northeastern Qinghai-Xizang Plateau(QXP), where humans first settled permanently in large numbers in the QXP, has varying sedimentary environments that are extremely sensitive to human activities. In contrast to other regions of the QXP, the northeastern sector boasts a richer array of climatic and environmental reconstruction sequences. This distinctive feature renders it an exemplary locale for investigating the stratigraphic boundary of the Anthropocene. Through in-depth analysis and integration of existing paleoclimate and paleoenvironment sequences in the northeastern QXP, we draw the following conclusions:(1) Throughout the past millennium, the impact of human activities on the environment of the northeastern QXP has become increasingly significant, especially in the past 200–300 years, gradually overshadowing climatic factors.(2) Since AD 1950,multiple physicochemical indicators related to human activities in the northeastern QXP have shown exponential growth,forming a distinct peak within the past millennium and clearly depicting the global “Great Acceleration” phenomenon and its development process.(3) Intensified human activities have driven swift environmental shifts and “decoupled” the interplay between climatic variations and the ecological environment, propelling the northeastern QXP into the “Early Anthropocene”from the “Late Holocene”. On the basis of the above findings, we construct a model suitable for identifying the stratigraphic boundary of the Anthropocene in the northeastern QXP and note that since the ecological environment in the northeastern QXP has entered the “Early Anthropocene”, the climate signals of certain physicochemical indicators in sediments are gradually becoming weaker, whereas the signals of

关键词： Anthropocene Qinghai-Xizang Plateau (QXP) Climate change Environmental evolution Human activities

Surface Topological Glycosylation-Mediated Mucoadhesion of Bacteria

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Chinese Journal of Chemistry 2024年第13期42卷 1447-1455页

作者： Xiao Kuang Xiaobing Liu Ju Chen Wenyan Lv mengmeng zhang Huan Chen Feng Wu Jinyao Liu School of Life Sciences Shanghai UniversityShanghai 200444China Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine Institute of Molecular MedicineState Key Laboratory of Systems Medicine for CancerRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and National Center for Translational MedicineShanghai Jiao Tong UniversityShanghai 200240China College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234China

Sugar moieties present on bacterial surface serve as pivotal regulators of bacterial *** adjusting the abundance and distribution of surface sugar moieties can offer an important approach to manipulating bacterial behavior,but has been proven to be ***,surface topological glycosylation is reported to mediate the interaction of bacteria with mucous *** functionalized by sugar moieties with different branching are synthesized through iterative Michael addition and amide condensation *** a copper-catalyzed azide-alkyne cycloaddition,the resulting compounds with different branching structures can be attached onto bacterial surface that is modified with azido *** a proof-of-concept study,a set of topologically glycosylated probiotics(TGPs)is prepared using linear,two-branched,and tetra-branched compounds,*** interaction between mucin and TGPs was studied and the results demonstrate that,compared to unmodified bacteria,TGPs exhibit an enhanced adhesive capacity to mucin,which increases with the branching *** binding trend is observed in ex vivo colonic mucus adhesion experiments and bacteria glycosylated with tetra-branched compounds display the highest binding *** work proposes a chemical method to tune the abundance and distribution of sugar moieties on bacteria,providing unique significant insights into the manipulation of bacterial behavior through surface modification.

关键词： Topochemistry Bacteria Glycosylation Surface modification Mucoadhesion Click chemistry

The Immersive Experience of Cultural Tourism in Yunnan

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China's Tibet 2024年第4期35卷 58-63页

作者： Yang Meixiao(Text/Photos) zhang mengmeng(Text/Photos) 无不详 CTIS

The integration of culture and tourism is not only a concept but also a vivid practice in Dechen Tibetan Autonomous Prefecture and Lijiang,Yunnan Province in recent ***,the high-quality development of the culture and tourism industry promotes not only economic growth but also cultural *** its historical profundity and unique cultural charm this land on the southwestern border of China epitomizes the unity in diversity of the Chinese *** is inherited in tourism,while tourism is improvedbyculture.

关键词： culture tourism southwestern

Modulating the p-band center of carbon nanofibers derived from Co spin state as anode for high-power sodium storage

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Chinese Chemical Letters 2024年第1期35卷 537-541页

作者： Zhijia zhang Yuwen Zhao Yanhao Wei mengmeng zhang Chunsheng Li Yan Sun Jianmin Ma Yong Jiang School of Materials Science and Engineering State Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and TechnologySuzhou 215009China School of Chemistry Tiangong UniversityTianjin 300387China School of Electronic and Information Engineering Institute of Quantum Materials and DevicesTiangong UniversityTianjin 300387China

Carbon nanofibers(CNFs)have received extensive and in-depth studied as anodes for sodium-ion batteries(SIBs),and yet their initial Coulombic efficiency and rate capability remain enormous challenge at practical ***,CNFs anchored with cobalt nanocluster(CNFs-Co)were prepared using chemical vapor deposition and thermal reduction *** as-prepared CNFs-Co shows a high initial Coulombic efficiency of 91%and a high specific discharge capacity of 246 mAh/g at 0.1 A/g after 200 cycles as anode for ***,the CNFs-Co anode still delivers a high cycling stability with 108 mAh/g after 1000 cycles at 10 A/*** excellent electrochemical properties could be attributed to the involved spin state Co,which endows CNFs with large interplanar spacing(0.39 nm)and abundant vacancy ***,the spin state Co downshifts the p-band center of carbon and strengthens the Na+adsorption energy from-2.33 eV to-2.64 eV based on density functional theory *** novel strategy of modulating the carbon electronic structure by the spin state of magnetic metals provides a reference for the development of high-performance carbon-based anode materials.

关键词： Carbon nanofibers Chemical vapor deposition Spin state p-band center Sodium-ion battery

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A Novel Agricultural Data Sharing Mode Based on Rice Disease Identification

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Plant Diseases and Pests 2024年第2期15卷 9-16页

作者： mengmeng zhang Xiujuan WANG Mengzhen KANG Jing HUA Haoyu WANG Feiyue WANG State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Beijing Engineering Research Center of Intelligent Systems and Technology Institute of AutomationChinese Academy of SciencesBeijing 100190China Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China State Key Laboratory for Management and Control of Complex System Institute of AutomationChinese Academy of SciencesBeijing 100190China

In this paper,a variety of classical convolutional neural networks are trained on two different datasets using transfer learning *** demonstrated that the training dataset has a significant impact on the training results,in addition to the optimization achieved through the model ***,the lack of open-source agricultural data,combined with the absence of a comprehensive open-source data sharing platform,remains a substantial *** issue is closely related to the difficulty and high cost of obtaining high-quality agricultural data,the low level of education of most employees,underdeveloped distributed training systems and unsecured data *** address these challenges,this paper proposes a novel idea of constructing an agricultural data sharing platform based on a federated learning(FL)framework,aiming to overcome the deficiency of high-quality data in agricultural field training.

关键词： Rice disease and pest identification Convolutional neural networks Distributed training Federated learning(FL) Open-source data sharing platform

Strengthening heterogeneous strain in FeCoNiMo-based high-entropy alloy for boosting triiodide reduction and hydrogen evolution reaction

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Strengthening heterogeneous strain in FeCoNiMo-based high-en...