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基于A位元素置换策略合成新型MAX相材料Ti_3ZnC_2

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无机材料学报 2019年第1期34卷 60-64页

作者：李勉李友兵罗侃 LU Jun EKLUND Per PERSSON Per ROSEN Johanna hultman lars 都时禹黄政仁黄庆中国科学院宁波工业技术与工程研究所核能材料工程实验室(筹) 宁波315201 Department of Physics Chemistry and Biology (IFM) Link?ping University

MAX相材料是一类兼具金属和陶瓷特性的三元层状材料,在高温导电、耐磨、耐腐蚀和耐辐照损伤等方面性能优异。目前已经合成出的MAX相材料已有70余种,但A位元素一直局限在ⅢA和ⅣA主族元素,如Al、Si、Ga等,而以副族元素占据A位的MAX相鲜... 详细信息

MAX相材料是一类兼具金属和陶瓷特性的三元层状材料,在高温导电、耐磨、耐腐蚀和耐辐照损伤等方面性能优异。目前已经合成出的MAX相材料已有70余种,但A位元素一直局限在ⅢA和ⅣA主族元素,如Al、Si、Ga等,而以副族元素占据A位的MAX相鲜有报道。本研究以Ti_3AlC_2为前驱体,利用熔盐中的A位置换反应,制备出了A位为Zn元素的全新MAX相材料Ti_3ZnC_2。结合X射线衍射、扫描电子显微镜和透射电子显微镜等分析手段对Ti_3ZnC_2的成分和结构进行了确认,并通过密度泛函理论对Ti_3ZnC_2的结构稳定性和晶格参数进行了确定。进一步通过热力学计算对Fe、Co、Ni、Cu等几种元素的A位置换反应进行了预测,发现采用这几种元素的氧化物进行置换反应在热力学上也都具有可行性。本研究所提出的元素置换策略是在保持MAX相六方层状晶体结构的基础上,利用Al、Zn在高温下形成共晶产物实现Zn原子向A层内的迁移,而熔盐介质的存在促进了反应动力学。本方法巧妙地避免了MAX相传统合成过程中竞争相的形成,如M-A合金相,因此可以用于探索更多未知的MAX相材料。

关键词： MAX相置换反应 Ti3ZnC2

Revisiting the stretch-induced force deficit:A systematic review with multilevel meta-analysis of acute effects

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Journal of Sport and Health Science 2024年第6期13卷 805-819页

作者： Konstantin Warneke lars Hubertus Lohmann Institute of Human Movement Science Sport and HealthUniversity of GrazGraz 8010Austria Institute of Sport Science Alpen-Adria University of KlagenfurtKlagenfurt am Worthersee 9020Austria Institute of Human Movement and Exercise Physiology University of JenaJena 07749Germany

Background:When recommending avoidance of static stretching prior to athletic performance,authors and practitioners commonly refer to available systematic ***,effect sizes(ES)in previous reviews were extracted in major part from studies lacking control conditions and/or prepost testing ***,currently available reviews conducted calculations without accounting for multiple study outcomes,with ES:0.03 to 0.10,which would commonly be classified as ***:Since new meta-analytical software and controlled research articles have appeared since 2013,we revisited the available literatures and performed a multilevel meta-analysis using robust variance estimation of controlled prepost trials to provide updated ***,previous research described reduced electromyography activity—also attributable to fatiguing training routines—as being responsible for decreased subsequent *** second part of this study opposed stretching and alternative interventions sufficient to induce general fatigue to examine whether static stretching induces higher performance losses compared to other exercise ***:Including 83 studies with more than 400 ES from 2012 participants,our results indicate a significant,small ES for a static stretch-induced maximal strength loss(ES=0.21,p=0.003),with high magnitude ES(ES=0.84,p=0.004)for stretching durations60 s per bout when compared to passive *** opposed to active controls,the maximal strength loss ranges between ES:0.17 to0.28,p<0.001 and 0.040 with mostly no to small ***,stretching did not negatively influence athletic performance in general(when compared to both passive and active controls);in fact,a positive effect on subsequent jumping performance(ES=0.15,p=0.006)was found in ***:Regarding strength testing of isolated muscles(e.g.,leg extensions or calf raises),our results confirm previous ***,since no(or even positive)e

关键词： Static stretching Maximal strength Athletic performance Performance testing

Electrochemical Lithium Storage Performance of Molten Salt Derived V_(2)SnC MAX Phase

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Nano-Micro Letters 2021年第10期13卷 266-275页

作者： Youbing Li Guoliang Ma Hui Shao Peng Xiao Jun Lu Jin Xu Jinrong Hou Ke Chen Xiao Zhang Mian Li Per OÅPersson lars hultman Per Eklund Shiyu Du Zhifang Chai Zhengren Huang Na Jin Jiwei Ma Ying Liu Zifeng Lin Qing Huang Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingbo 315201ZhejiangPeople’s Republic of China Qianwan Institute of CNiTECH Ningbo 315336People’s Republic of China College of Materials Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China CIRIMAT UMR CNRS 5085 UniversitéToulouse III-Paul Sabatier118 route de Narbonne31062 Toulouse Cedex 9France Department of Physics Chemistry and Biology(IFM)Linköping University58183 LinköpingSweden School of Machine Engineering Dongguan University of TechnologyDongguan 523808People’s Republic of China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804People’s Republic of China

MAX phases are gaining attention as precursors of two-dimensional MXenes that are intensively pursued in applications for electrochemical energy ***,we report the preparation of V_(2)SnC MAX phase by the molten salt method.V_(2)SnC is investigated as a lithium storage anode,showing a high gravimetric capacity of 490 mAh g−1 and volumetric capacity of 570 mAh cm^(−3) as well as superior rate performance of 95 mAh g^(−1)(110 mAh cm^(−3))at 50 C,surpassing the ever-reported performance of MAX phase ***-ported by operando X-ray diffraction and density functional theory,a charge storage mechanism with dual redox reaction is proposed with a Sn-Li(de)alloying reaction that occurs at the edge sites of V_(2)SnC particles where Sn atoms are exposed to the electrolyte followed by a redox reaction that occurs at V_(2)C layers with *** study offers promise of using MAX phases with M-site and A-site elements that are redox active as high-rate lithium storage materials.

关键词： MAX phase Molten salt Lithium storage High-rate Energy storage

Small molecular decoys in Alzheimer's disease

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Neural Regeneration Research 2024年第8期19卷 1658-1659页

作者： Sho Oasa Valentina L.Kouznetsova Igor F.Tsigelny lars Terenius Department of Clinical Neuroscience Center for Molecular MedicineKarolinska InstitutetStockholmSweden San Diego Supercomputer Center University of California San DiegoLa JollaCAUSA Department of Neurosciences University of California San DiegoLa JollaCAUSA Department of Clinical Neuroscience Karolinska University HospitalKarolinska InstitutetStockholmSweden

Recent progress in the treatment of Alzheimer’s disease(AD)using antibodies against amyloid sustains amyloid generation as a key process in *** formation starts with two amyloidbeta(Aβ)molecules interacting(dimer formation)followed by an accelerating build-up of socalled protofibrils,which turn into fibrils,which accumulate in the characteristic plaques.

关键词： Alzheimer decoy Aβ

Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第4期13卷 509-520页

作者： Konstantin Warneke Gerit Plöschberger lars H.Lohmann Eric Lichtenstein Daniel Jochum Stanislav D.Siegel Astrid Zech David G.Behm Institute of Sport Science University of KlagenfurtKlagenfurt am Wörthersee 9020Austria Department of Human Motion Science and Exercise Physiology Friedrich Schiller UniversityJena 07749Germany Department Sport Exercise and HealthUniversity of BaselBasel 4052Switzerland Department of Health Sciences and Technology ETH ZurichZurich 8092Switzerland School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.JohnsNL A1C 5S7Canada

Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous ***,these effects were also reported in response to various other active and passive interventions that induce responses such as enhanced muscle ***,we hypothesized that acute ROM enhancements could be induced by a wide variety of interventions other than stretching or foam rolling that promote an increase in muscle ***:After a systematic search in PubMed,Web of Science,and SPORTDiscus databases,38 studies comparing the effects of stretching and foam rolling with several other interventions on ROM and passive properties were *** studies had 1134 participants in total,and the data analysis resulted in 140 effect sizes(ESs).ES calculations were performed using robust variance estimation model with ***:Study quality of the included studies was classified as fair(PEDro score=4.58)with low to moderate certainty of *** showed no significant differences in ROM(ES=0.01,p=0.88),stiffness(ES=0.09,p=0.67),or passive peak torque(ES=-0.30,p=0.14)between stretching or foam rolling and the other identified *** plots revealed no publication ***:Based on current literature,our results challenge the established view on stretching and foam rolling as a recommended component of warm-up *** lack of significant difference between interventions suggests there is no need to emphasize stretching or foam rolling to induce acute ROM,passive peak torque increases,or stiffness reductions.

关键词： Range of motion Passive properties Muscletendon unit Muscle tissue

Otolaryngology residency program factors associated with female resident representation

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 7-11页

作者： Julia E.Canick James C.Campbell Charles R.Woodard lars J.Grimm Alissa M.Collins Duke University School of Medicine DurhamNorth CarolinaUSA Department of Head and Neck Surgery&Communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Department of Radiology Duke University School of MedicineDurhamNorth CarolinaUSA

Objective:Female representation in the field of otolaryngology is *** is the first point at which medical school graduates specialize in a chosen field and thus represents an opportunity to recruit and train more female *** study sought to identify program factors associated with greater female representation among resident ***:Departmental websites of all 124 otolaryngology residency programs in the United States and Puerto Rico were examined for a list of *** programs with a resident roster available,the genders of residents,faculty,program directors,and chairpersons were *** and city population for each program was also recorded,as was female resident *** were compared using Pearson Chi‐squared univariate ***:1,632 residents and 2,605 faculty were included in the analysis of 109 *** median female resident representation was 40%.Programs with larger faculty sizes,more female faculty,and urban location were associated with an above‐median female resident *** with a larger residency cohort approached significance regarding above‐median female resident *** female faculty representation,program director gender,chairperson gender,and US region were not associated with variation in female resident ***:Greater female otolaryngology residency representation was associated with programs having an urban location and greater numbers of female and total *** was also likely that a larger resident cohort size may affect female resident *** proportions of female faculty,program director,and chairperson gender,as well as the US region,were not associated with variation in female resident gender representation.

关键词： gender program director recruitment residency training

Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS

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Research in Astronomy and Astrophysics 2024年第3期24卷 129-143页

作者： Jia-Qi Wang Xiao-Jun Jiang Jie Zheng Hanna Kellermann Arno Riffeser Liang Wang Karen A.Collins Allyson Bieryla lars A.Buchhave Steve B.Howell Elise Furlan Eric Girardin Joao Gregorio Eric Jensen Felipe Murgas Mesut Yilmaz Sam Quinn Xing Gao Ruo-Yu Zhou Frank Grupp Hui-Juan Wang CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy Of SciencesBeijing 10010China University of Chinese Academy of Sciences Beijing 100049China University Observatory Munich Scheinertrsse 1.D-81679 MunichGemany Max Planck Institute for Extraterrestrial Physics Giessenbachstr.1D-85748 GarchingGermany National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China Center for Astrophysics Harvard&Smithsonian60 Garden Street.CambridgeMA 02138USA National Space Institute Technical University of DenmarkElektrovejDK-2800 KgsLyngbyDenmark NASA Ames Research Center Moffett FieldCA 94035USA NASA Exoplanet Science Institute Caltech/IPACMail Code 100-221200 E.California Blvd.PasadenaCA91125USA Grand Pra Observatory Switzerland Department of Physics Washington UniversitySt.LouisMO 63130.USA Department of Physics and Astronomy Swarthmore CollegeSwarthmorePA 19081USA Instituto de Astrofísica de Canarias(IAC) E-38205 La Laguna.TenerifeSpain Departamento de Astrofísica Universidad de La LagunaSpain Dept.of Astronomy and Space Sciences Ankara UniversityTandogan 06100AnkaraTurkey Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Urumqi No.1 Senior High School Urumqi 830002China Lijiang Gemini Observatory Lijiang 674199China

We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 *** candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium *** analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Objects of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period ***-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric *** measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041RJ and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(J) and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1).

关键词： planets and satellites fundamental parameters-planets and satellites gaseous planets-stars fundamental parameters-stars low-mass-methods data analysis-techniques photometric-techniques spectroscopic

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筑牢工业信息安全防线

流程工业 2024年第3期 22-23,25页

作者： Nicolas Bennerscheid lars StephanBüldt Sebastian Dännart TUEG-Schillings公司 Infodas公司

安联2023年的风险报告分析称,除了业务中断之外,网络风险是全球企业面临的最大风险。因此,需要通过做好基础网络安全监测与防御,避免企业受到网络攻击的可能性。对于流程工业的任何一家公司来说,一旦受到网络攻击,如果不及时采取措施将... 详细信息

安联2023年的风险报告分析称,除了业务中断之外,网络风险是全球企业面临的最大风险。因此,需要通过做好基础网络安全监测与防御,避免企业受到网络攻击的可能性。对于流程工业的任何一家公司来说,一旦受到网络攻击,如果不及时采取措施将会遭到致命打击。2023年《安联风险晴雨表》显示,网络风险如IT中断、勒索软件攻击或数据泄露,一直被认为是全球企业面临的最大风险。

关键词：网络风险网络攻击勒索软件流程工业工业信息安全致命打击数据泄露业务中断

从模型到应用:基于生态系统服务权衡的乡村生态修复规划工具研究

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园林 2024年第3期41卷 4-12页

作者：董楠楠王怡琪 Harald Zepp lars Gruenhagen Malte Bührs Christin Busch 魏维轩同济大学建筑与城市规划学院上海200092 波鸿鲁尔大学地理学系波鸿44801 ILS-国家和城市发展研究所有限公司多特蒙德D-44135

在全球范围内的气候变化背景下,具有多种功能和服务价值的乡村生态空间成为当下国际生态规划研究与合作的关注热点之一。为实现乡村生态空间的精准管理与规划,中德双方围绕联合课题“生态系统服务概念在德国鲁尔与中国大都市区韧性发展... 详细信息

在全球范围内的气候变化背景下,具有多种功能和服务价值的乡村生态空间成为当下国际生态规划研究与合作的关注热点之一。为实现乡村生态空间的精准管理与规划,中德双方围绕联合课题“生态系统服务概念在德国鲁尔与中国大都市区韧性发展模式下的绿色基础设施规划应用”进行了深入探索。在土地利用与土地覆盖类型的基础上,进一步识别了生物群落类型,并基于调节、供给、文化三大生态系统服务类型,选取了评估生态系统服务供需权衡的指标和对应权重,构建了乡村生态空间规划场景下的生态系统服务价值评测模型。以上海市水库村为例,运用该课题的评测模型,初步评估了典型乡村生态规划场景下的生态系统服务价值。最后,从应用尺度、研究范围以及操作流程三个方面总结了该评测模型的优化方向。

关键词：乡村生态修复生态系统服务供需权衡决策辅助工具

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