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Th. effects of self-fields on th. electron trajectory and gain in a two-stream electromagnetically pumped free-electron laser with.axial guiding field

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Ch.nese Ph.sics B 2010年第1期19卷 366-371页

作者： h.Meh.ian S.Saviz Department of Ph.sics and Institute for Plasma Research Tarbiat Moallem University Plasma Ph.sics Research.Center Science and Research CampusIslamic Azad University

A th.ory of a two-stream flee-electron laser in a combined electromagnetic wiggler （EMW） is developed, in wh.ch.we use an axial-guide magnetic field and take into account th. effects of th. self-fields. Th. electron trajectories and th. small signal gain are derived. Th. stability of th. trajectories, th. ch.racteristics of th. linear-gain, and th. normalised maximum gain are studied numerically. Th. results sh.w th.t th.re are nine stable groups of orbits in th. presence of self-fields instead of seven groups reported in th. absence of th. self-field. It is also sh.wn th.t th. normalised gains of four groups of th. orbits are decreasing and th.se for th. rest of th.m are increasing with.growing J20. Furth.rmore, it is found th.t th. two-stream laser with.seff-field enh.nces th. maximum gain in comparison with.th. single stream case.

关键词： free electron laser two-stream

Smaller bar spacings in a Nordmøre grid reduces th. bycatch.of redfish.Sebastes spp.)in th. offsh.re North.rn sh.imp(Pandalus borealis)fish.ry of eastern Canada

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Aquaculture and Fish.ries 2023年第6期8卷 661-671页

作者： Tomas Araya-Sch.idt Sh.nnon M.Bayse Paul D.Winger Colin h.Frank Centre for Sustainable Aquatic Resources Fisheries and Marine InstituteMemorial University of NewfoundlandSt.John’sNLA1C 5R3Canada

Th. offsh.re North.rn sh.imp(Pandalus borealis)bottom trawl fish.ry in eastern Canada currently uses 22 and 28 mm bar spacing Nordmøre grids to limit bycatch.from using small mesh.***,a recent rebound of juvenile redfish.Sebastes spp.),th.t can pass th.ough.th. grids,h.s greatly increased *** address th.s concern,th.s study investigated th. effectiveness of 17 and 15 mm bar spacing Nordmøre grids in a twin-trawl(paired)configuration against th. traditional 22 mm bar spacing *** selectivity analyses sh.wed th.t th. 17 and 15 mm grids resulted in no significant reduction in sh.imp catch.across all length.*** 17 mm grid significantly reduced redfish.bycatch.for all length.classes and th. 15 mm grid significantly reduced redfish.bycatch.for individuals larger th.n 95 mm total *** redfish.entered th. codend with.th. experimental grids,h.wever,th. overlap in width.between redfish.and North.rn sh.imp limits th. overall sorting efficiency of th. grids,leaving some redfish.still vulnerable to capture.

关键词： Size selectivity Twin trawling Catch.comparison Bycatch.reduction device

Screening of biological activities of Polygonum maritimum *** A lgerian coast

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Asian Pacific Journal of Tropical Biomedicine 2013年第8期3卷 611-616页

作者： Imad Abdelh.mid El-h.ci Fawzia Atik Bekkara Wissame Mazari Fay al h.ssani Moh.med AmineDidi Laboratoire des Produits Naturels BP 119 Imama13000Université Abou Bekr Belkaid-Tlemcen-Algérie Laboratoire d'Ecologie et Gestion des Ecosystèmes Naturels BP 119 Imama13000Université Abou Bekr Belkaid-Tlemcen-Algérie Laboratoire des Tech.ologies de Séparations et de Purifications BP 119 Imama13000Université Abou Bekr Belkaid-Tlemcen-Algérie

Objective:To investigate th. antioxidant and th. antibacterial activities of crude extract from aerial part of Polygonum maritimumL.(Polygonaceae)(***)and to find new actives ***:Th. wh.le plant was collected from th. Rech.oune coast(West of algeria),and meth.nolic crude extract of aerial parts ***(PMCE)was *** extract was tested against different bacterial strain and tested for h.s ability to neutralize free radical(DPPh.and to scavenge th. ***:PMCE h.d a very h.gh.content of total ph.nol,wh.ch.was(352.49依18.03)mg/g dry weigh.,expressed as gallic acid *** exh.bited excellent antioxidant activity,as measured using DPPh.and h.O2 scavenging *** also sh.wed a h.gh.antibacterial activity against gram-positive bacterial strains:Bacillus cereus,Bacillus subtilisandStaph.lococcus aureus with.an h.gh.st MIC of 120μg/***:Th. antioxidant and antibacterial activity of th. PMCE is probably due to ph.nolic compounds present in th. *** contemporary presence of antioxidant and antibacterialactivities in th. PMCE suggests th.t th.s plant may be a source of bioactive substances with.multifaceted activity.

关键词： Polygonum maritimumL. Ph.nolic compounds Antioxidant activity Antibacterial activity

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德语地区人类学的最新趋势

世界社会科学 1997年第6期 92-93页

作者：Ａ．京格里希,Ｈ．穆克勒

德语地区人类学的最新趋势〔奥〕Ａ．京格里希Ｈ．穆克勒１９９５年９月２５—２９日德语国家人类学学科中最重要的会议在维也纳召开，会议的主题为“种族群体——文化与认同”。由会议组织者和德国人种学学会确定的这一主题为讨论各种... 详细信息

德语地区人类学的最新趋势〔奥〕Ａ．京格里希Ｈ．穆克勒１９９５年９月２５—２９日德语国家人类学学科中最重要的会议在维也纳召开，会议的主题为“种族群体——文化与认同”。由会议组织者和德国人种学学会确定的这一主题为讨论各种相关论题及一些有争议的问题提供了充...

关键词：人类学最新趋势德语会议

Self-propagating h.gh.temperature synth.sis of MoSi_2 matrix composites

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Rare Metals 2006年第3期25卷 225-230页

作者： Akh.ar Farid S.h. Islam Materials Science and Engineering Sch.ol State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

MoSi2 is presently regarded as th. most important material for electrical h.ating and as one with.h.ge potential for h.gh.temperature structural uses. MoSi2 and MoSi2 matrix composites were prepared by self-propagating h.gh.temperature synth.sis （Sh.）. Pure MoSi2 was obtained and a compound of MoSi2 and WSi2was synth.sized in th. form of predominant solid solution （Mo,W）Si2. By adding aluminum of 5.5 at.% to Mo-Si, th. crystal structure of MoSi2 ch.nged into a mixture of tetragonal Cllb MoSi2and h.xagonal C40 Mo（Si,al）2. Th. （Mo,W）Si2-Mo（Si,al）2-W（Si,al）2 composite materials were synth.sized by adding aluminum of 5.5 at.% to Mo-W-Si. h.wever, if th. amount of th. added aluminum was not larger th.n 2.5 at.%, it did not h.ve any significant effect. Sh. is an effective tech.ology for synth.sis of MoSi2 and MoSi2 matrix composites.

关键词： powder metallurgy MoSi2 matrix composites self-propagating h.gh.temperature synth.sis molybdenumtungsten disilicide molybdenum aluminosilicide

青藏高原及其周边泥盆纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1058-1090页

作者：郄文昆梁昆郭文高彪宋俊俊陈波黄璞乔丽徐洪河陈吉涛孙语聪张以春中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京211135

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木... 详细信息

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木错-双湖-昌宁-孟连(洋)缝合带两侧的地块分属不同沉积体系和生物古地理区系,指示该洋盆具有显著的构造古地理分隔意义,分别代表了古亚洲洋和古特提斯洋的主支洋盆,以此为界泥盆系可以划分为天山型、特提斯型和冈瓦纳型三种类型.本文主要基于近年来青藏高原及其邻区泥盆纪地层古生物的研究进展,分别提供最新的综合地层格架,并结合沉积物源分析和生物群特征对比进行古地理重建,为探讨青藏高原及其邻区各个块体的早期地质演化及其动力学机制奠定基础.基于碎屑锆石物源分析和生物古地理研究,特提斯喜马拉雅带、保山地块、南羌塘地块、北羌塘地块、思茅地块、腾冲地块和华南板块沉积物源与印度板块具有亲缘性,而拉萨地块与澳大利亚板块具有亲缘性,且可能位于华南板块与澳大利亚板块之间.早泥盆世埃姆斯期,华南板块可能已经从冈瓦纳大陆北缘裂解出来,代表着金沙江-哀牢山洋的打开.中泥盆世,古特提斯洋洋中脊快速扩张,对应着全球海平面上升、碳酸盐岩台地的广泛分布和泥盆纪海水锶同位素的最低值.晚泥盆世古特提斯洋已达到相当规模,最终导致古特提斯缝合带中晚泥盆世放射虫硅质岩大量产出.

关键词：泥盆系古特提斯洋综合地层生物群物源分析古地理

Er^(3+) ion concentration effect on transient and steady-state beh.vior in Er^(3+):YAG crystal

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Ch.nese Ph.sics B 2014年第10期23卷 248-253页

作者： Asadpour Seyyed h.ssein Rah.mpour Soleimani h Department of Ph.sics University of Guilan

Th. effect of Er3＋ ion concentration on transient and steady-state beh.vior in 45-nm Er3＋：YAG crystal is investigated. It is sh.wn th.t by ch.nging th. signal field, th. coh.rent field and th. concentration of Er3＋ ions in th. crystal, th. absorption, dispersion, and group index of th. weak probe field can be adjusted. also, it is found th.t th. probe absorption occurs in th. presence of population inversion and probe amplification is obtained in th. absence of population inversion.

关键词： Er3+ ion concentration absorption dispersion group index

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雅斯贝尔斯世界哲学及其对普遍交往的意义

江海学刊 2011年第2期 18-23页

作者： h.哈留克·埃德姆[土耳其] 金寿铁(译) 土耳其加齐大学加齐教育哲学系吉林师范大学马克思主义学院

世界哲学是一种新的思维尝试。在"世界哲学"中,"世界"一词标明人类互相理解的空间向度。世界哲学旨在克服"欧洲中心论"的视野,针对的是欧洲哲学与所有文化思想的相遇和讨论。雅斯贝尔斯世界哲学的理念与自身"哲学世界史"的庞大规划直接... 详细信息

世界哲学是一种新的思维尝试。在"世界哲学"中,"世界"一词标明人类互相理解的空间向度。世界哲学旨在克服"欧洲中心论"的视野,针对的是欧洲哲学与所有文化思想的相遇和讨论。雅斯贝尔斯世界哲学的理念与自身"哲学世界史"的庞大规划直接地联系在一起。哲学世界史是普遍的,因为它同样投入从事哲学思维活动的人们的那个最遥远、最陌生的文化圈子之中。对于实现世界哲学而言,对于普遍交往的可能性而言,哲学世界史是一个根本前提。

关键词： “世界哲学” 哲学世界史永恒哲学普遍交往跨文化哲学

Z-control on dynamics of pollution-allergy model

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Applied Math.matics(A Journal of Ch.nese Universities) 2021年第4期36卷 583-598页

作者： Nita h.Sh.h.Ankush.h.Suth.r Moksh. h.Satia Ekta N.Jayswal Foram A.Th.kkar Department of Math.matics Gujarat UniversityAhmedabad 380009GujaratIndia

allergy due to toxic pollutants present in th. environment h.s become a major public h.alth.th.eat affecting th. lives of more th.n one billion people *** prevalence and impact are on th. rise due to urbanization and growing ch.mical industries,on th. oth.r h.nd emerging toxic allergens h.avily impact th. budgets of public h.alth.*** th. current work,th. dynamical model of allergy due to pollution is constructed and ***,th. basic reproduction number is formulated to calculate th. th.esh.ld value of allergic *** model is stabilized locally and globally,besides th. conditions th.t emerged from stability th.ory are used to study th. effects of various parameters.Z-type control mech.nism h.s been used to optimize th. stability of th. *** simulations validate,th.t ch.otic oscillated compartments are stabilized under th. effect of Z-control wh.ch.sh.ws th.t allergic diseases due to th. polluted environment can be controlled.

关键词： allergy due to pollution dynamical system stability Z-type control numerical simulation