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On-Surface Synthesis of Anthracene-Fused Zigzag Graphene Nanoribbons from 2,7-Dibromo-9,9′-bianthryl Reveals Unexpected Ring Rearrangements

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Precision Chemistry 2024年第2期2卷 81-87页

作者： Xiushang Xu Amogh Kinikar Marco Di Giovannantonio Carlo A.Pignedoli Pascal Ruffieux Klaus Müllen Roman Fasel Akimitsu Narita Max Planck Institute for Polymer research 55128 MainzGermany Organic and Carbon Nanomaterials Unit Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0495Japan Empa Swiss Federal Laboratories for Materials Science and Technologynanotech@surfaces Laboratory8600 DübendorfSwitzerland Institute of Structure of Matter-CNR(ISM-CNR) 00133 RomaItaly Institute of Physical Chemistry Johannes Gutenberg University Mainz55128 MainzGermany Department of Chemistry Biochemistry and Pharmaceutical SciencesUniversity of Bern3012 BernSwitzerland

On-surface synthesis has emerged as a powerful strategy to fabricate unprecedented forms of atomically precise graphene nanoribbons(GNRs).However,the on-surface synthesis of zigzag GNRs(ZGNR)has met with only limited ***,we report the synthesis and on-surface reactions of 2,7-dibromo-9,9′-bianthryl as the precursor towardπ-extended *** by scanning tunneling microscopy and high-resolution noncontact atomic force microscopy clearly demonstrated the formation of anthracene-fused *** skeletal rearrangements were also observed,which could be explained by intramolecular Diels-Alder *** calculations of the electronic properties of the anthracene-fused ZGNRs revealed spin-polarized edge-states and a narrow bandgap of 0.20 eV.

关键词： On-surface synthesis Graphene nanoribbon On-surface reaction Rearrangement Edge state

Small-scale self-driving cars:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： Felipe Caleffi Lauren da Silva Rodrigues Joice da Silva Stamboroski Brenda Medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil Mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language journals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACM Digital Library,and TRID databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a major benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review

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Reactivation of hepatitis B virus infection – an important aspect of multifaceted problem

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World Journal of Gastroenterology 2024年第26期30卷 3193-3197页

作者： Sergey Morozov Sergey Batskikh Department of Gastroenterology Hepatology and NutritionFederal Research Center of NutritionBiotechnology and Food SafetyMoscow 115446Russia Department of Hepatology Moscow Clinical Scientific Center N.A.A.S.LoginovMoscow 111123Russia

In this editorial we comment on the article published in the recent issue of the W orld Journal of *** focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of *** prevalence of PHB is underestimated due to the lack of population testing ***,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune *** we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment.

关键词： Occult hepatitis B virus infection Hepatitis B virus reactivation Previous hepatitis B Cancer Autoimmune disorders

Identification of abnormal tribological regimes using a microphone and semi-supervised machine-learning algorithm

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Friction 2022年第4期10卷 583-596页

作者： Vigneashwara PANDIYAN Josef PROST Georg VORLAUFER Markus VARGA Kilian WASMER Laboratory for Advanced materials Processing(LAMP) Swiss Federal Laboratories for Materials Science and Technology(Empa)Thun CH-3602Switzerland AC2T research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria

Functional surfaces in relative contact and motion are prone to wear and tear,resulting in loss of efficiency and performance of the workpieces/*** occurs in the form of adhesion,abrasion,scuffing,galling,and scoring between ***,the rate of the wear phenomenon depends primarily on the physical properties and the surrounding *** the integrity of surfaces by offline inspections leads to significant wasted machine time.A potential alternate option to offline inspection currently practiced in industries is the analysis of sensors signatures capable of capturing the wear state and correlating it with the wear phenomenon,followed by in situ classification using a state-of-the-art machine learning(ML)*** this technique is better than offline inspection,it possesses inherent disadvantages for training the ML ***,supervised training of ML models requires the datasets considered for the classification to be of equal weightage to avoid *** collection of such a dataset is very cumbersome and expensive in practice,as in real industrial applications,the malfunction period is minimal compared to normal ***,classification models would not classify new wear phenomena from the normal regime if they are *** a promising alternative,in this work,we propose a methodology able to differentiate the abnormal regimes,i.e.,wear phenomenon regimes,from the normal *** is carried out by familiarizing the ML algorithms only with the distribution of the acoustic emission(AE)signals captured using a microphone related to the normal *** a result,the ML algorithms would be able to detect whether some overlaps exist with the learnt distributions when a new,unseen signal *** achieve this goal,a generative convolutional neural network(CNN)architecture based on variational auto encoder(VAE)is built and *** the validation procedure of the proposed CNN architectures,we were

关键词： surface integrity acoustic emission auto encoders condition monitoring wear prediction

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Molecular heterostructure by fusing graphene nanoribbons of different lengths through a pentagon ring junction

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Nano research 2022年第9期15卷 8465-8469页

作者： Qiang Sun Hao Jiang Yuyi Yan Roman Fasel Pascal Ruffieux materials Genome Institute Shanghai UniversityShanghai 200444China Empa Swiss Federal Laboratories for Materials Science and TechnologyDübendorf 8600Switzerland Department of Chemistry Biochemistry and Pharmaceutical SciencesUniversity of BernBern 3012Switzerland

Graphene nanoribbons(GNRs)have attracted great research interest because of their widely tunable and unique electronic *** required atomic precision of GNRs can be realized via on-surface synthesis *** this work,through a surface assisted reaction we have longitudinally fused the pyrene-based graphene nanoribbons(pGNR)of different lengths by a pentagon ring junction,and built a molecular junction structure on Au(111).The electronic properties of the structure are studied by scanning tunneling spectroscopy(STS)combined with tight binding(TB)*** pentagon ring junction shows a weak electronic coupling effect on graphene nanoribbons,which makes the electronic properties of the two different graphene nanoribbons connected by a pentagon ring junction analogous to type I semiconductor heterojunctions.

关键词： graphene nanoribbons(GNRs) scanning tunneling spectroscopy(STS) non-contact atomic force microscopy(nc-AFM) tight-binding(TB)calculations junction structure

Volume and surface effects on two-photonic and three-photonic processes in dry co-doped upconversion nanocrystals

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Nano research 2022年第3期15卷 2362-2373页

作者： Bettina Grauel Christian Würth Christian Homann Lisa Krukewitt Elina Andresen Janina Roik Sebastian Recknagel Markus Haase Ute Resch-Genger federal Institute for materials research and testing(BAM) Division 1.2 BiophotonicsRichard-Willstaetter-Str.1112489 BerlinGermany federal Institute for materials research and testing(BAM) Division 1.6 Inorganic Reference MaterialsRichard-Willstaetter-Str.1112489 BerlinGermany Institute of Chemistry of New materials Department Biology/ChemistryUniversity OsnabrueckBarbarastr.749076 OsnabrueckGermany Department of Anesthesiology and Intensive Care Medicine University Medical Center RostockSchillingallee 3518057 RostockGermany

Despite considerable advances in synthesizing high-quality core/shell upconversion(UC)nanocrystals(NC;UCNC)and UCNC photophysics,the application of near-infrared(NIR)-excitable lanthanide-doped UCNC in the life and material sciences is still hampered by the relatively low upconversion luminescence(UCL)of UCNC of small size or thin protecting *** obtain deeper insights into energy transfer and surface quenching processes involving Yb^(3+) and Er^(3+) ions,we examined energy loss processes in differently sized solid core NaYF_(4) nanocrystals doped with either Yb^(3+)(YbNC;20%Yb^(3+))or Er^(3+)(ErNC;2%Er^(3+))and co-doped with Yb^(3+) and Er^(3+)(YbErNC;20%Yb^(3+) and 2%Er^(3+))without a surface protection shell and coated with a thin and a thick NaYF_(4) shell in comparison to single and co-doped bulk *** studies at 375 nm excitation demonstrate back-energy transfer(BET)from the ^(4)G_(11/2) state of Er^(3+) to the ^(2)F_(5/2) state of Yb^(3+),through which the red Er^(3+) ^(4)F_(9/2) state is efficiently *** power density(P)-dependent steady state and time-resolved photoluminescence measurements at different excitation and emission wavelengths enable to separate surface-related and volume-related effects for two-photonic and three-photonic processes involved in UCL and indicate a different influence of surface passivation on the green and red Er3+*** intensity and lifetime of the latter respond particularly to an increase in volume of the active UCNC *** provide a three-dimensional random walk model to describe these effects that can be used in the future to predict the UCL behavior of UCNC.

关键词： upconversion luminescence core/shell nanoparticles dopant concentration lifetime volume effect surface quenching

Thermodynamic assessment of Mg-Ga binary system

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中国有色金属学报：英文版 2010年第3期20卷 450-457页

作者：孟凡桂王江戎茂华刘立斌金展鹏 School of materials Science and Engineering Central South University of Forestry and Technology School of materials Science and Engineering Central South University swiss federal laboratories for materials testing and research Laboratory for Joining and Interface Technology School of Science Hunan University of Technology

In order to obtain the thermodynamic description of the Mg-Ga binary system,the thermodynamic assessment of the system was carried out using the CALPHAD method through Thermo-calc software package based on the evaluation of all available experimental data from the published *** solution phases,including liquid,hcp(Mg) and orthorhombic(Ga),were described by the substitutional solution model,of which the excess Gibbs energies were expressed with the Redlich-Kister ***,all intermetallic compounds,Mg5Ga2,Mg2Ga,MgGa,MgGa2 and Mg2Ga5,were modeled as stoichiometric compounds.A set of self-consistent thermodynamic parameters formulating the Gibbs energies of various phases in the Mg-Ga binary system were obtained *** much better agreement is achieved between the calculated results and the reported experimental data.

关键词：二元体系热力学评估镁金属间化合物实验数据能量自洽相图计算

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Active-site and interface engineering of cathode materials for aqueous Zn–gas batteries

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Nano research 2023年第2期16卷 2325-2346页

作者： Wenxian Liu Jinxiu Feng Tianran Wei Qian Liu Shusheng Zhang Yang Luo Jun Luo Xijun Liu College of materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China Ministry of Education(MOE)Key Laboratory of New Processing Technology for Non-Ferrous Metals and materials and Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsSchool of ResourceEnvironmentsand MaterialsGuangxi UniversityNanning 530004China Institute for Advanced Study Chengdu UniversityChengdu 610106China College of Chemistry Zhengzhou UniversityZhengzhou 450000China Empa Swiss Federal Laboratories for Materials Science and TechnologySwiss Federal Institute of Technology in Zurich(ETH)DomainDübendorf CH-8600Switzerland Hong Kong Productivity Council(HKPC) Hong Kong 999077China School of materials Science and Engineering Tianjin University of TechnologyTianjin 300384China

Aqueous rechargeable Zn–gas batteries are regarded as promising energy storage and conversion devices due to their high safety and inherent environmental ***,the energy efficiency and power density of Zn–gas batteries are restricted by the kinetically sluggish cathode reactions,such as oxygen evolution reaction(OER)during charging and oxygen reduction reaction(ORR)/carbon dioxide reduction reaction(CO_(2)RR)/nitrogen reduction reaction(NRR)/nitric oxide reduction reaction(NORR)during *** this review,battery configurations and fundamental reactions in Zn–gas batteries are first introduced,including Zn–air,Zn-CO_(2),Zn-N_(2),and Zn-NO ***,recent advances in active site engineering for enhancing the intrinsic catalytic activities of cathode catalysts are ***,the structure and surface regulation strategies of cathode materials for optimizing the three-phase interface and improving the performance of Zn–gas batteries are ***,some personal perspectives for the future development of Zn–gas batteries are presented.

关键词： Zn–gas batteries electrocatalysis single-atom catalysts chemical doping heterostructure interface

Perspectives on electrochemical nitrogen fixation catalyzed by two-dimensional MXenes

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materials Reports(Energy) 2022年第1期2卷 3-16页

作者： Tiezhu Guo Di Zhou Chuanfang(John)Zhang Laboratory for Functional Polymers EmpaSwiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 129CH-8600DübendorfSwitzerland Key Laboratory of Multifunctional materials and Structures Ministry of EducationSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiPR China

Ammonia is the most basic raw material in industrial and agricultural *** current industrial production of ammonia relies on the Haber-Bosch process with high energy *** overcome this shortcoming,the development of electrocatalytic ammonia synthesis under moderate conditions is considered as a potential alternative *** two-dimensional(2D)MXenes family has been proved promising as electrocatalysts,but from the currently available literature,it is hard to find a systematic review on MXenes-catalyzed ammonia *** in the present review,we summarize the key perspectives on that topic in recent years as well as outline,from a prospective view,strategies of catalyst *** analyze in detail the methods for preparing high performance MXenes-based catalysts and the corresponding underlying mechanisms,and also discuss the criteria and potential challenges,expecting to provide inspiration for the development of efficient MXenes-based route to electrochemical ammonia fixation.

关键词： 2D materials MXenes Ammonia synthesis Electrocatalytic nitrogen reduction reaction (NRR) Electrocatalysts