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Revisiting the sodium-ion storage capability of hard carbon in carbonate-based electrolytes via a sodium-metal-free protocol

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Science China Chemistry 2024年第7期67卷 2240-2247页

作者： Gaopan Liu Yanbing Mo Jiawei Chen Yu Peng Xiao Zhu Fei Wang Xiaoli Dong Yongyao Xia Department of Chemistry and Shanghai Key laboratory of Molecular Catalysis and Innovative Materials Institute of New EnergyLaboratory of Advanced MaterialsFudan UniversityShanghai 200438China

Common evaluation methodology of sodium(Na)-containing two-electrode or three-electrode configurations overlooks the interference from highly reactive Na metal,leading to the underestimation or inconsistent performance of low-potential hard carbon(HC)***,the trap of Na metal was systematically investigated with or without applied current,uncovering its inadequacy as the reference or counter electrode in different configurations.A Na-metal-free three-electrode protocol is proposed for evaluating the actual Na^(+)-storage capability of the typical low-potential HC *** avoiding Na crosstalk and precisely controlling the working electrode's potential,the actual electrochemical performance of HC in the carbonate esterbased electrolyte can be recognized with high capacity of 222 mAh g^(-1)at 2 C and 113 mAh g^(-1)at 5 C,correcting the misunderstanding of the inferior performance of HC in coin-type half cells(68%and 50%undervaluation at 2 C and 5 C,respectively).The advanced protocol is expected to reduce misunderstandings or underestimation due to evaluation methods and to guide the development of high-performance battery materials.

关键词： highly reactive sodium potential drift carbonate ester sodium-metal-free protocol sodium storage capability

Alignment of inertialess spheroidal particles in flow-structure-dominated regions of turbulent channel flow:shape effect

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Acta Mechanica Sinica 2024年第8期40卷 45-66页

作者： Zhiwen Cui Lihao Zhao Applied Mechanics laboratory Department of Engineering MechanicsTsinghua UniversityBeijing100084China laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing100084China

The alignment of elongated fibers and thin disks is known to be significantly influenced by the presence of fluid coherent structures in near-wall turbulence(Cui et al.2021).However,this earlier study is confined to the spheroids with infinitely large or small aspect ratio,and the shape effect of finite aspect ratio on the alignment is not *** current study investigates the shape-dependent alignment of inertialess spheroids in structure-dominated regions of channel *** utilizing an ensemble-averaged approach for identifying the structure-dominated regions,we analyze the eigensystem of the linear term matrix in the Jeffery equation,which is governed by both particle shape and local fluid velocity *** contrast to earlier conventional analysis based on local vorticity and strain rate,our findings demonstrate that the eigensystem of the Jeffery equation offers a convenient,effective,and universal framework for predicting the alignment behavior of inertialess spheroids in turbulent *** leveraging the eigensystem of the Jeffery equation,we uncover a diverse effect of fluid coherent structures on spheroid alignment with different particle ***,we provide explanations for both shape-independent alignments observed in vortical-core regions and shape-dependent alignments around near-wall streamwise vortices.

关键词： Non-spherical particle Direct numerical simulation Wall turbulence Particle-laden flow

A credible traffic prediction method based on self-supervised causal discovery

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Science China(Information Sciences) 2024年第5期67卷 244-258页

作者： Dan WANG Yingjie LIU Bin SONG State Key laboratory of Integrated Services Networks Xidian University

Next-generation wireless network aims to support low-latency, high-speed data transmission services by incorporating artificial intelligence(AI) technologies. To fulfill this promise, AI-based network traffic prediction is essential for pre-allocating resources, such as bandwidth and computing power. This can help reduce network congestion and improve the quality of service(QoS) for users. Most studies achieve future traffic prediction by exploiting deep learning and reinforcement learning, to mine spatio-temporal correlated variables. Nevertheless, the prediction results obtained only by the spatio-temporal correlated variables cannot reflect real traffic changes. This phenomenon prevents the true prediction variables from being inferred, making the prediction algorithm perform poorly. Inspired by causal science, we propose a novel network traffic prediction method based on self-supervised spatio-temporal causal discovery(SSTCD). We first introduce the Granger causal discovery algorithm to build a causal graph among prediction variables and obtain spatio-temporal causality in the observed data, which reflects the real reasons affecting traffic ***, a graph neural network(GNN) is adopted to incorporate causality for traffic prediction. Furthermore,we propose a self-supervised method to implement causal discovery to to address the challenge of lacking ground-truth causal graphs in the observed data. Experimental results demonstrate the effectiveness of the SSTCD method.

关键词： wireless network traffic prediction causal discovery self-supervised

Cobalt-Catalyzed Switchable[4+1]and[4+1+1]Spirocyclization of Aromatic Amides with 2-Diazo-1H-indene-1,3(2H)-dione:Access to Spiro Indene-2,1'-isoindolinones and Spiro Isochroman-3,1'-isoindolinones

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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin Li Mengmeng Xie Jingyu Li Nana Shen Xinying Zhang Xuesen Fan State Key laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-*** the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]*** the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen *** general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3,1'-isoindolinones 3d Transition metals Cobalt-catalyzed C-H Activation Switchable[4+1]and[4+1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3(2H)-dione

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： Qiang Luo Wei Li Zhi-Hui Liu Feng Wang Zhi-Chao Liu Fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

Learnware:small models do big

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Science China(Information Sciences) 2024年第1期67卷 39-50页

作者： Zhi-Hua ZHOU Zhi-Hao TAN National Key laboratory for Novel Software Technology Nanjing University

There are complaints about current machine learning techniques such as the requirement of a huge amount of training data and proficient training skills,the difficulty of continual learning,the risk of catastrophic forgetting,and the leaking of data privacy/*** research efforts have been focusing on one of those concerned issues separately,paying less attention to the fact that most issues are entangled in *** prevailing big model paradigm,which has achieved impressive results in natural language processing and computer vision applications,has not yet addressed those issues,whereas becoming a serious source of carbon *** article offers an overview of the learnware paradigm,which attempts to enable users not to need to build machine learning models from scratch,with the hope of reusing small models to do things even beyond their original purposes,where the key ingredient is the specification which enables a trained model to be adequately identified to reuse according to the requirement of future users who know nothing about the model in advance.

关键词： artificial intelligence machine learning learnware

Design and preparation of a crosslinkable,oil-resistant,and bio-based elastomer from fumarate

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Science China Chemistry 2024年第2期67卷 622-631页

作者： Hui Yang Haijun Ji Xinxin Zhou Shihan Yang Liwei Li Chaoying Sun Weiwei Lei Runguo Wang Liqun Zhang Beijing State Key laboratory of Organic-Inorganic Composites&Beijing laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing100029China Hubei Key laboratory of Polymer Materials Faculty of Materials Science and EngineeringHubei UniversityWuhan430062China

Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion *** glass-transition temperatures of PDEFMV,adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio,ranged from-36.1 to-14.8 ℃.The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/*** designing the molecular structure,vinyl chloroacetate was used to provide active sites for subsequent vulcanization and *** active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network *** achieve the desired properties,carbon black(CB,N330) was incorporated to reinforce PDEFMV,leading to the formation of PDEFMV/CB composites.A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB *** immersion in IRM903 oil at temperatures of 150 and 200 ℃ for 72 h,the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber(AR)/CB,indicating that PDEFMV exhibited superior oil ***,the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures(150,200,and 250 ℃).The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications.

关键词： diethyl fumarate molecular design bio-based elastomer solvent-free synthetic route high-temperature oil resistance

Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li Hao-Ran Shen Shao-Juan Wang Hao Zhang Jian Hu Rui Xin Xiao-Li Sun Shou-Ke Yan Key laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Pathologically relevant aldoses and environmental aldehydes cause cilium disassembly via formyl group-mediated mechanisms

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Journal of Molecular Cell Biology 2024年第1期16卷 15-28页

作者： Te Li Min Liu Fan Yu Song Yang Weiwen Bu Kai Liu Jia Yang Hua Ni Mulin Yang Hanxiao Yin Renjie Hong Dengwen Li Huĳie Zhao Jun Zhou Haihe laboratory of Cell Ecosystem State Key Laboratory of Medicinal Chemical BiologyTianjin Key Laboratory of Protein ScienceCollege of Life SciencesNankai UniversityTianjin 300071China laboratory of Tissue Homeostasis Haihe Laboratory of Cell EcosystemTianjin 300462China Center for Cell Structure and Function Collaborative Innovation Center of Cell Biology in Universities of ShandongShandong Provincial Key Laboratory of Animal Resistance BiologyCollege of Life SciencesShandong Normal UniversityJinan 250014China

Carbohydrate metabolism disorders(CMDs),such as diabetes,galactosemia,and mannosidosis,cause ciliopathy-like multiorgan ***,the mechanistic link of cilia to CMD complications is still poorly ***,we describe significant cilium disassembly upon treatment of cells with pathologically relevant aldoses rather than the corresponding sugar ***,environmental aldehydes are able to trigger cilium disassembly by the steric hindrance effect of their formyl *** studies reveal that aldehydes stimulate extracellular calcium influx across the plasma membrane,which subsequently activates the calmodulin-Aurora A-histone deacetylase 6 pathway to deacetylate axonemal microtubules and triggers cilium *** vivo experiments further show that Hdac6 knockout mice are resistant to aldehyde-induced disassembly of tracheal cilia and sperm *** findings reveal a previously unrecognized role for formyl group-mediated cilium disassembly in the complications of CMDs.

关键词： carbohydrate metabolism disorder aldose aldehyde cilium disassembly formyl group calcium influx HDAC6