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High rodent abundance increases seed removal but decreases scatter-hoarding and seedling recruitment along an elevational gradient

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Integrative Zoology 2023年第5期18卷 843-858页

作者： Fei YU linjun zhang Yang WANG Xianfeng YI Shuang zhang Jianmin MA Zimei DONG Guangwen CHEN Keming MA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina College of Life Sciences Henan Normal UniversityXinxiangChina College of Life Sciences Qufu Normal UniversityQufuChina

The distributions of small rodents in mountainous environments across different elevations can provide important information regarding the effects of climate change on the dispersal of plant ***,few studies of oak forest ecosystems have compared the elevational patterns of sympatric rodent diversity,seed dispersal,seed bank,and seedling ***,we tested the differences in the seed disperser composition and abundance,seed dispersal,seed bank abundance,and seedling recruitment for Quercus wutaishanica along 10 elevation levels in the Taihang Mountains,*** results provide strong evidence that complex asymmetric seed dispersal and seedling regeneration exist along an elevational *** abundance of rodents had a significant negative correlation with the elevation and the seed removal rates peaked and then declined with increasing *** seed removal rates were higher at middle and lower elevations than higher elevations but acorns were predated by 5 species of seed predators at middle and lower elevations,and thus,there was a lower likelihood of recruitment compared with those dropped beneath mother oaks at higher *** importantly,the number of individual seeds in the seed bank and seedlings increased with the elevation,although dispersal services were reduced at sites lacking *** conditional mutualists,the rodents could possibly act as antagonistic seed predators rather than mutualistic seed dispersers at low and middle elevations,thereby resulting in the asymmetric pattern of rodent and seedling abundance with increasing elevation to affect the community assembly and ecosystem functions on a large spatial scale.

关键词： elevation rodent seed bank seed dispersal seedling distribution

A recyclable polyurethane with characteristic thermal stiffening behavior via B-N coordination with reversible B-O bonds

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Science China Materials 2024年第10期67卷 3339-3346页

作者： Hui Xiong linjun zhang Qi Wu Jinrong Wu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Key Laboratory of Composite Materials on Electrical Insulation National Energy AdministrationJiangsu Shemar Electric Co.Ltd.Nantong 226017China

Thermal softening is an inevitable process in the physical ***(PU),a typical commercial material,is constructed by physical networks,which undergoes the serious thermal decay on mechanical properties at high ***,a physically cross-linked PU with a unique thermal stiffening behavior has been developed by incorporating B–N coordination with reversible B–O *** B–N coordination can significantly improve the mechanical properties of the *** reversible B–O bonds(temperature dependent reversible transformation between B–OH and B–O–B)are conducive to constructing more multicoordination macromolecular crosslinking points and more stable B–N coordination bonds at high temperature,endowing the PU with the special thermal stiffening behavior for the first *** thermal stiffening behavior compensates for the bond breakage and the network destruction caused by heat,significantly expands the rubbery plateau and delays the entire chain motion of the thermoplastic *** a result,the terminal flow occurs at a higher temperature up to 200°*** modulus retention ratio of the materials is up to 87%even at 145oC,which is much higher than that of the existing PU elastomer with the physical network and even some covalent cross-link ***,the physical network ensures the recyclability of the PU,and the thermal stiffening behavior is still obtained in recycled *** work provides a simple strategy to impart thermal stiffening behavior to the physically crosslinked PU,thereby significantly extending the operating temperature range of thermoplastic PU,which can potentially expand the scopes of PU in applications under harsh conditions.

关键词： recyclable polyurethane B-N coordination reversible B-O bonds thermal stiffening behavior

知觉训练和日本留学生汉语辅音送气/不送气特征的习得

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语言教学与研究 2009年第4期 85-90页

作者：张林军北京语言大学汉语学院 100083

本文探讨知觉训练在日本留学生习得汉语辅音送气/不送气特征中的作用,发现:知觉训练不但可以促进感知,还可以改善发音;知觉训练的效果可以迁移到具有相同区别性特征的其他音位上;知觉训练的效果可以长期保持,发音能力可以得到持续改善... 详细信息

本文探讨知觉训练在日本留学生习得汉语辅音送气/不送气特征中的作用,发现:知觉训练不但可以促进感知,还可以改善发音;知觉训练的效果可以迁移到具有相同区别性特征的其他音位上;知觉训练的效果可以长期保持,发音能力可以得到持续改善。研究结果表明知觉训练可以有效克服语音习得过程中的"化石化"现象,对进一步改善对外汉语语音教学的效果和提高语音教学的效率具有重要的现实意义。

关键词：知觉训练送气/不送气语音习得化石化

音段和韵律信息对汉语外语口音感知及言语可懂度的影响

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世界汉语教学 2015年第2期29卷 242-249页

作者：张林军北京语言大学语言科学院语言病理与脑科学研究所

本研究借助语音编辑和合成技术,通过对英语母语者和日语母语者的言语进行音段替换和韵律替换,考察了音段和韵律信息对汉语外语口音感知和言语可懂度的影响及其相对重要性。研究发现:在外语口音方面,音段和韵律替换都会带来外语口音感的... 详细信息

本研究借助语音编辑和合成技术,通过对英语母语者和日语母语者的言语进行音段替换和韵律替换,考察了音段和韵律信息对汉语外语口音感知和言语可懂度的影响及其相对重要性。研究发现:在外语口音方面,音段和韵律替换都会带来外语口音感的明显降低,但韵律替换的作用更大;在言语可懂度方面,韵律替换的影响不大,而音段替换却会带来可懂度的显著上升。结果表明,韵律和音段信息对于汉语外语口音感知和言语可懂度的影响存在较大差别,也说明外语口音强弱和言语可懂度并非简单的对应关系。

关键词：音段韵律外语口音言语可懂度

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唐代监牧置废发展考论

农业考古 2021年第4期 182-187页

作者：张林君扬州大学社会发展学院

监牧是唐代统治者设立的官营养马机构,其发展经历了三个阶段:唐初兴起、高武时期衰微和唐中后期提振。唐初获得突厥战马和隋代遗马是有迹可循的,其时间早于贞观,再于陇右地区广开监牧蕃马。高武时期,永隆夏州失马与垂拱后耗马都是监牧... 详细信息

监牧是唐代统治者设立的官营养马机构,其发展经历了三个阶段:唐初兴起、高武时期衰微和唐中后期提振。唐初获得突厥战马和隋代遗马是有迹可循的,其时间早于贞观,再于陇右地区广开监牧蕃马。高武时期,永隆夏州失马与垂拱后耗马都是监牧颓然的表现,主要与突厥寇边、平定叛乱、政局变化等背景有关。玄宗时重振马政,使马数稍复;而安史之乱与吐蕃入侵,导致陇右的监牧尽废;唐中后期仍营建了六个监牧,大多存在时间不长,其置废都有一定的现实原因,也暴露出监牧延续过程中的多种矛盾与阻碍。虽然唐代监牧置废发展曲折,但唐王朝始终设立官营的马匹生产部门,显示了朝廷对战备资源的需求及其背后隐含的政治变迁。

关键词：唐代监牧马政安史之乱飞龙使

李斯特钢琴作品中的技术成分及其艺术价值分析——以《十二卷钢琴技巧练习》为例

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星海音乐学院学报 2019年第4期 135-148页

作者：张琳君华东师范大学音乐学院

在李斯特的钢琴作品中,对钢琴技术的贡献具有里程碑式的意义。文章以《十二卷钢琴技巧练习》为例对李斯特钢琴作品中的各类技术成分进行分析,李斯特钢琴作品中的技术概括为四个种类:钢琴基本技术、拓展型基本技术、复合技术和综合配置... 详细信息

在李斯特的钢琴作品中,对钢琴技术的贡献具有里程碑式的意义。文章以《十二卷钢琴技巧练习》为例对李斯特钢琴作品中的各类技术成分进行分析,李斯特钢琴作品中的技术概括为四个种类:钢琴基本技术、拓展型基本技术、复合技术和综合配置的复合技术。而所谓的综合配置的复合技术即是炫技性钢琴技术,并归总结其艺术价值。

关键词：李斯特钢琴技术炫技性技术《十二卷钢琴技巧练习》

论昭武九姓胡与唐代马政——从康善达墓出土谈起

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宁夏社会科学 2021年第4期 193-201页

作者：张林君扬州大学社会发展学院江苏扬州225100

新出土康善达墓是研究昭武九姓胡与唐代马政的有利史料之一,它揭示了此二者的紧密联系,并反映出九姓胡入仕马政系统的事实。唐初朝廷设立蕃养官马的监牧机构,九姓胡仕为其长官——牧监需要有一定的门荫出身,再从禁军武职转为这种技术型... 详细信息

新出土康善达墓是研究昭武九姓胡与唐代马政的有利史料之一,它揭示了此二者的紧密联系,并反映出九姓胡入仕马政系统的事实。唐初朝廷设立蕃养官马的监牧机构,九姓胡仕为其长官——牧监需要有一定的门荫出身,再从禁军武职转为这种技术型职事官,而且他们多来自徙居原州的昭武九姓望族,以善于牧马的技能优势供职于唐代重要且特殊的监牧。随着高宗后期马政系统出现使职差遣,大量九姓胡以马政使职的身份获得了更多军政方面的权力。昭武九姓胡与唐代马政之间的互动关系渐趋明显,体现了朝廷秉持人尽其才的用人制度考量,这对九姓胡及马政都产生着深刻的影响。

关键词：唐代昭武九姓胡牧监马政康善达

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日本留学生汉语声调的范畴化知觉

语言教学与研究 2010年第3期 9-15页

作者：张林军北京语言大学汉语学院 100083

本研究从范畴化知觉的角度探讨了不同水平的日本留学生对汉语声调的感知,发现没有汉语经验的"零起点"学习者对汉语声调的知觉是连续性的,初级水平的学习者汉语声调的范畴化知觉能力显著提高,中级水平的学习者汉语声调的范畴化知觉能力... 详细信息

本研究从范畴化知觉的角度探讨了不同水平的日本留学生对汉语声调的感知,发现没有汉语经验的"零起点"学习者对汉语声调的知觉是连续性的,初级水平的学习者汉语声调的范畴化知觉能力显著提高,中级水平的学习者汉语声调的范畴化知觉能力接近汉语母语者的水平,但精细化程度仍然有待提高。研究结果有助于深入理解母语语音系统对声调范畴化知觉的影响以及作为第二语言的声调范畴化知觉能力的发展。

关键词：声调范畴化知觉日本留学生

A fast-healing and high-performance metallosupramolecular elastomer based on pyridine-Cu coordination

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Science China Materials 2022年第7期65卷 1943-1951页

作者： Hui Liu Qiaoqiao Shen linjun zhang Shiyu Gu Yan Peng Qi Wu Hui Xiong Hao zhang Lijuan Zhao Guangsu Huang Jinrong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610066China

Elastomers easily undergo a catastrophic failure as soon as a crack is introduced by mechanical ***,it is extremely important for elastomers to possess fast healing ability,which enables the quick reparation of ***,developing elastomers with fast self-healing ability and high mechanical strength is highly ***,we fabricate a metallosupramolecular elastomer by facilely introducing pyridine-Cu coordination into a copolymer of ethyl acrylate and vinyl ***,the pyridine-Cu coordination has a strong photothermal effect,which readily increases the sample temperature to 60℃ in 30 s under near-infrared *** this temperature,the sticky reptation modes are activated and thus serve as the driving force for network reorganization and fast self-healing of the metallosupramolecular *** with a tensile strength of 10 MPa,the scratched and completely fractured samples can be healed within 2 min and 3 h,***,during the damage and healing processes,the break and reformation of the coordination bonds can be tracked through laser confocal micro-Raman *** provides a microscopic methodology to monitor the bond-level healing kinetics of metallosupramolecular polymers.

关键词： metallosupramolecular elastomer photothermal effect molecular dynamics healing mechanism laser confocal micro-Raman