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Si-induced insertion of Li into SiC to form Li-rich SiC twin crystal

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Particuology 2023年第3期74卷 56-63页

作者： Di Zhang Chenxi Zhang Feng Lu Hairong Jiang Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing100084China

The energy density of Li-ion batteries is closely related to the capacity and average voltage of cathode materials.Unfortunately,current cathode materials either have low capacity or voltage,which limits the development of high-energy-density Li-ion batteries.This has given challenge to many attempts to develop new cathode materials with high capacity and voltage.In this study,we find that Li easily inserts into the(111)plane of SiC in the presence of Si,and a well-organized Li-rich SiC twin crystal is formed.Ultraviolet-visible diffuse reflectance spectra and electrochemical test results suggest that this Li-rich SiC twin crystal possesses the band gap energy of 3.5 eV and charging capacity of 1979 mAh/g at the current density of 200 mA/g,making it a promising candidate for the cathode material in high-capacity Li-ion batteries.X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy results reveal that Si-induced Li insertion contributes to the changes in the surface species and structure of pristine SiC.These findings suggest that the Li-rich SiC twin crystal raises new possibilities for the development of high-capacity cathode materials and merits further investigation to expand its application scope.

关键词： Si Li insertion SiC Li-rich twin crystal CathodeLi-ion batteries

Product Systems of C^(*)-correspondences and Baaj-Skandalis Duality

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Acta Mathematica Sinica,English Series 2023年第2期39卷 240-256页

作者： fei fei MIAO Li Guang WANG wei YUAN School of Mathematical Sciences Qufu Normal UniversityQufu273165China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

Let X={X_(p)}p∈Pbe a product system over a lattice ordered group(G,P)with coefficients in a C*-algebra A.In this paper,we study the reduced crossed product of the gauge coactionδof G on the Cuntz-Pimsner algebra NO_(X)^(r).When X is a product system of Morita equivalence bimodules,we show that the reduced crossed product of the gauge coaction is Morita equivalent to the C*-algebra A.

关键词： Cuntz-Pimsner algebras product systems reduced crossed products Morita equivalence

Research on swarm intelligence optimization algorithm

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The Journal of China Universities of Posts and Telecommunications 2020年第3期27卷 1-20,30页

作者： Fei Wei Liu Cong Hu Sheng Hubei Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan 430068China Hubei Collaborative Innovation Center for High-Efficiency Utilization of Solar Energy Hubei University of Technologywuhan 430068China Wuhan Hua'an Science and Technology Co. Ltd.Postdoctoral WorkstationWuhan 430068.China

The bionics-based swarm intelligence optimization algorithm is a typical natural heuristic algorithm whose goal is to find the global optimal solution of the optimization problem.It simulates the group behavior of various animals and uses the information exchange and cooperation between individuals to achieve optimal goals through simple and effective interaction with experienced and intelligent individuals.This paper first introduces the principles of various swarm intelligent optimization algorithms.Then,the typical application of these swarm intelligence optimization algorithms in various fields is listed.After that,the advantages and defects of all swarm intelligence optimization algorithms are summarized.Next,the improvement strategies of various swarm intelligence optimization algorithms are explained.Finally,the future development of various swarm intelligence optimization algorithms is prospected.

关键词： bionics natural heuristic algorithm swarm intelligence algorithm intelligent computing

Does City Shape Affect China's Economic Development?

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China & World Economy 2024年第1期32卷 21-56页

作者： wei Zou fei Yang Economics and Management School Wuhan UniversityChina

This paper constructs a general equilibrium spatial urban model and measures city geometric compactness using the patch-shape index based on evidence from satellite imagery and basic vector maps of China.It adopts the ordinary least squares and instrumental variable approaches to examine the effect of city shape on the urban development of 279 Chinese cities at or above the prefecture level.The empirical results show that there was a significant negative correlation between city shape and economic outcomes.Specifically,every 1 percentage point increase in the patch-shape index led to a decrease in city-scale GDP by 0.009 percent,housing prices by 0.044 percent,and wages by 0.024 percent.More compact urban layouts attracted an inflow of households and firms,stimulated city economic growth,and were associated with increased housing prices and wage rates.The paper considers the cities'initial conditions,trends in population changes(expanding,shrinking,and stagnant cities),and geographic factors,and finds that the results are robust.An array of policy implications can be drawn from the research.

关键词： city footprint compactness economic development urban spatial shape

A new polar motion prediction method combined with the difference between polar motion series

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Geodesy and Geodynamics 2022年第6期13卷 564-572页

作者： Leyang Wang wei Miao fei Wu Faculty of Geomatics East China University of TechnologyNanchang 330013China Key Laboratory of Mine Environmental Monitoring and Improving Around Poyang Lake Ministry of Natural ResourcesNanchang 330013China

After the first Earth Orientation Parameters Prediction Comparison Campaign(1 st EOP PCC),the traditional method using least-squares extrapolation and autoregressive(LS+AR)models was considered as one of the polar motion prediction methods with higher accuracy.The traditional method predicts individual polar motion series separately,which has a single input data and limited improvement in prediction accuracy.To address this problem,this paper proposes a new method for predicting polar motion by combining the difference between polar motion series.The X,Y,and Y-X series were predicted separately using LS+AR models.Then,the new forecast value of X series is obtained by combining the forecast value of Y series with that of Y-X series;the new forecast value of Y series is obtained by combining the forecast value of X series with that of Y-X series.The hindcast experimental comparison results from January 1,2011 to April 4,2021 show that the new method achieves a maximum improvement of 12.95%and 14.96%over the traditional method in the X and Y directions,respectively.The new method has obvious advantages compared with the differential method.This study tests the stability and superiority of the new method and provides a new idea for the research of polar motion prediction.

关键词： Earth rotation parameters Polar motion prediction LS+AR Differences between series Mean absolute error

RNA modifications in cellular metabolism:implications for metabolism-targeted therapy and immunotherapy

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1565-1594页

作者： wei-wei Liu Si-Qing Zheng Tian Li Yun-fei fei Chen Wang Shuang Zhang fei Wang Guan-Min Jiang Hao Wang Department of Laboratory Medicine The First Affliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina School of Clinical Medicine Shandong UniversityJinanChina Core Unit of National Clinical Research Center for Laboratory Medicine HefeiChina Neurosurgical Department The First Affliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina Department of Clinical Laboratory The Fifth Affliated HospitalSun Yat-sen UniversityZhuhaiChina

Cellular metabolism is an intricate network satisfying bioenergetic and biosynthesis requirements of cells.Relevant studies have been constantly making inroads in our understanding of pathophysiology,and inspiring development of therapeutics.As a crucial component of epigenetics at post-transcription level,RNA modification significantly determines RNA fates,further affecting various biological processes and cellular phenotypes.To be noted,immunometabolism defines the metabolic alterations occur on immune cells in different stages and immunological contexts.In this review,we characterize the distribution features,modifying mechanisms and biological functions of 8 RNA modifications,including N6-methyladenosine(m6A),N6,2'-O-dimethyladenosine(m6Am),N1-methyladenosine(m1A),5-methylcytosine(m5C),N4-acetylcytosine(ac4C),N7-methylguanosine(m7G),Pseudouridine(V),adenosine-to-inosine(A-to-l)editing,which are relatively the most studied types.Then regulatory roles of these RNA modification on metabolism in diverse health and disease contexts are comprehensively described,categorized as glucose,lipid,amino acid,and mitochondrial metabolism.And we highlight the regulation of RNA modifications on immunometabolism,further influencing immune responses.Above all,we provide a thorough discussion about clinical implications of RNA modification in metabolism-targeted therapy and immunotherapy,progression of RNA modification-targeted agents,and its potential in RNAtargeted therapeutics.Eventually,we give legitimate perspectives for future researches in this field from methodological requirements,mechanistic insights,to therapeutic applications.

关键词： metabolism targeted alterations

Preparation of carbon nanotube films towards mechanical and electrochemical energy storage

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Nano Research 2023年第11期16卷 12411-12429页

作者： Yukang Zhu Yanbin wei Zhenxing Zhu Hongjie Yue Ziying He Qi Zhang Shijun Zhang Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Research Institute of Chemical Industry SINOPECBeijing 100013China

Due to unique and excellent properties,carbon nanotubes(CNTs)are expected to become the next-generation critical engineering mechanical and energy storage materials,which will play a key role as building blocks in aerospace,military equipment,communication sensing,and other cutting-edge fields.For practical application,the assembled macrostructures from individual CNTs are the common paradigms such as fibers or films.As the main representative,CNT films can not only retain the unique properties of their CNTs components,but also are more likely for mass-production than other macrostructures.Therefore,in this review,we focus on preparation of CNT films and discuss their emerging applications in the field of mechanical and electrochemical energy storage/conversion.Firstly,different preparation processes are systematically summarized.Then we introduce some typical strategies to improve their mechanical performances besides strengthening mechanism.Based on the progress of mass-production and performance optimization,we further discuss their potential utilization in mechanical and electrochemical energy storage/conversion devices.Finally,future perspectives for the development of CNT films in both production and application are proposed.We hope that this review will shed light on the preparation/assembly of CNT films and integrated application of excellent properties from individual to macroscopic dimensions.Moreover,the preparation and cross-scale application paradigms of CNT films also offer a good model for other macroscopic ordered assemblies of one-dimensional nanomaterials.

关键词： carbon nanotubes carbon nanotube film preparation mechanical strengthening energy storage

Mechanism involved in Danshen-induced fluid secretion in salivary glands

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World Journal of Gastroenterology 2015年第5期21卷 1444-1456页

作者： Fei Wei Mu-Xin wei Masataka Murakami Division of Physiological Sciences School of Life ScienceGraduate University for Advanced StudiesOkazaki 444-8585Japan Department of Traditional Chinese Medicine The first Affiliated Hospital with Nanjing Medical University Division of Cellular Physiology National Institute for Physiological SciencesNational Institutes of Natural SciencesOkazaki 444-8787Japan

AIM:Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia.METHODS:Submandibular glands were isolated from male Wistar rats under systemic anesthesia with pentobarbital sodium.The artery was cannulated and vascularly perfused at a constant rate.The excretory duct was also cannulated and the secreted saliva was weighed in a cup on an electronic balance.The weight of the accumulated saliva was measured every 3 s and the salivary flow rate was calculated.In addition,the arterio-venous difference in the partial oxygen pressure was measured as an indicator of oxygen consumption.In order to assess the mechanism involved in Dansheninduced fluid secretion,either ouabain(an inhibitor of Na+/K+ ATPase) or bumetanide(an inhibitor of NKCC1) was additionally applied during the Danshen stimulation.In order to examine the involvement of the main membrane receptors,atropine was added to block the M3 muscarinic receptors,or phentolamine was added to block the α1 adrenergic receptors.In order to examine the requirement for extracellular Ca2+,Danshen was applied during the perfusion with nominal Ca2+ free solution.RESULTS:Although Danshen induced salivary fluid secretion,88.7 ± 12.8 μL/g-min,n = 9,(the highest value around 20 min from start of DS perfusion was significantly high vs 32.5 ± 5.3 μL/g-min by carbamylcholine,P = 0.00093 by t-test) in the submandibular glands,the time course of that secretion differed from that induced by carbamylcholine.There was a latency associated with the fluid secretion induced by Danshen,followed by a gradual increasein the secretion to its highest value,which was in turn followed by a slow decline to a near zero level.The application of either ouabain or bumetanide inhibited the fluid secretion by 85% or 93%,and suppressed the oxygen consumption by 49% or 66%,respectively.These results indicated that Danshen activates Na+/K+ ATPase and NKCC1 to maintain Cl- release and K+ release for fluid secretion.Neither atropine or p

关键词： Salivary fluid secretion Xerostomia Chinese herb D

Role of Cyp19a1 in the female pathway of a freshwater turtle species(Mauremys reevesii)with temperature-dependent sex determination

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Zoological Research 2022年第1期43卷 81-84页

作者： Peng-fei Wu Xi-Feng Wang fei Gao wei-Guo Du Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The molecular mechanisms underpinning temperature-dependent sex determination(TSD)in reptiles have attracted great biological interest for many years.However,which genetic factors are essential for TSD remain elusive,especially regarding female sex determination.Cytochrome P450 family 19 subfamily A member 1(Cyp19a1)encodes the endoplasmic reticulum enzyme aromatase,which participates in the catalytic conversion of androgens to estrogens,and is implicated in sexual differentiation in many species.However,whether Cyp19a1 plays a critical role in determining gonadal sexual fate in TSD species remains to be elucidated.In the current study,Cyp19a1 exhibited a temperature-dependent and sexually dimorphic expression pattern,preceding gonadal sex differentiation in a TSD turtle species(Mauremys reevesii).Sexual phenotype of the turtles was successfully reversed by aromatase inhibitor treatment at the female-producing temperature(FPT).Furthermore,exogenous estradiol(E2)treatment led to complete male-to-female sex reversal at the male-producing temperature(MPT),accompanied by rapid up-regulation of Cyp19a1.Thus,Cyp19a1 appears to be essential for female sex determination in M.reevesii,suggesting a vital role in the female TSD pathway.

关键词： determination reversed treatment