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Responses of soil Collembolans to vegetation restoration in temperate coniferous and broad-leaved mixed forests

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Journal of Forestry Research 2020年第6期31卷 2333-2345页

作者： Chen Ma Xiuqin Yin huan xu Yan Tao School of Geographical Sciences Northeast Normal University5268 Renmin StreetChangchun 130024Jilin ProvincePeople’s Republic of China Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization 5268 Renmin StreetChangchun 130024Jilin ProvincePeople’s Republic of China Key Laboratory of Vegetation Ecology Ministry of EducationNortheast Normal UniversityChangchun 130024Jilin ProvincePeople’s Republic of China

A total of 900 soil samples were collected from five habitats,including primary coniferous broad-leaved mixed forests,secondary coniferous broad-leaved mixed forests,secondary broad-leaved forests,secondary shrub forests,and cutover lands in spring,summer,and autumn to quantify responses of soil Collembolans(springtails)to the restoration of vegetation of temperate coniferous and broad-leaved mixed *** results reveal that the taxonomic composition of Collembolans varied in the different stages of vegetation *** variations were in regard to their abundance and *** similarities existed in Collembola communities at different stages of vegetation restoration,and distribution patterns of Collembola taxa displayed an evenness throughout all *** Collembolans tended to gather on litter layers and soil surface;the highest abundance was found in the upper 5 cm soil layer during the initial stages of vegetation ***,Proisotoma,and Folsomia genera responded positively to the restoration of ***,responses of Ceratophysella and Parisotoma genera were *** addition,the Onychiuridae family did not respond to the vegetation restoration *** was concluded that restoration of vegetative cover can increase the abundance of soil Collembolans,but different genera respond differently.

关键词： Soil Collembolans(springtails) Temperate coniferous and broad-leaved mixed forests Vegetation restoration

The Crystallization Behavior of Biodegradable Poly(butylene succinate) in the Presence of Organically Modified Clay with a Wide Range of Loadings

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Chinese Journal of Polymer Science 2015年第4期33卷 576-586页

作者： Jing-bin Chen Jia-zhuang xu huan xu Zhong-ming Li 钟淦基雷军 College of Polymer Science and Engineering and State Key Laboratory of Polymer Materials Engineering Sichuan University

The crystallization behavior of poly（butylene succinate）（PBS） nanocomposites with a wide range of contents of clays was revealed. It was of interest to find that the crystallization rate of PBS was accelerated obviously at relatively low contents of clays; while a retarded crystallization kinetics and a decreased crystallinity of PBS were found in the nanocomposites with higher clay contents. Two interplaying effects existed in the nanocomposites, i.e., a suppression effect of clays on nucleation and a templating effect of clays on crystal growth, were clarified to contribute to this intriguing crystallization behavior.

关键词： Poly(butylene succinate) Clay Crystallization kinetics Biodegradable.

The 144–140 Ma Mafic Dykes in North China and Northeast China Indicating Regional Extensional Tectonic Setting

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 353-354页

作者： xu huan LIU Yongqing KUANG Hongwei PENG Nan College of Earth Science East China University of Technology Nanchang 330013 Jiangxi China Institute of Geological Survey East China University of Technology Nanchang 330013 Jiangxi China Institute of Geology Chinese Academy of Geological Sciences Beijing100037 China

Objective Previous studies indicate that the North China Craton（NCC）had undergone the loss of thickened lithosphere and fundamental change of physical and chemical property of lithospheric mantle（the destruction of NCC）during the *** peak period of the destruction of NCC is estimated to be 130 Ma,accompanied by widespread metamorphic core complex,rift basins,A-type granites and mafic dykes. However, it remains greatly controversial on the tectonic setting of NCC in the pre- 130Ma.

关键词： NCC Ma Mafic Dykes in North China and Northeast China Indicating Regional Extensional Tectonic Setting The 144 SHRIMP

Digital tildes ("~") may convey more: analyzing innovative uses of tildes in Chinese WeChat messages

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Language and Semiotic Studies 2023年第3期9卷 443-460页

作者： huan xu Dengshan Xia Beijing Foreign Studies University Haidian District Beijing China

Innovative uses of punctuation in online communication have become increasingly visible in research and public awareness since the 2000s,whereas studies on the innovative use of tildes("~")in digital use remain *** on a data set of 543 Chinese WeChat messages with sentence-final tildes,this article investigates the uses and functions of innovative tildes in online communication using quantitative data and follow-up *** findings suggest that:(1)The innovative tildes are deployed in messages implying sounds and performing speech acts in online communication,and they are more frequently used in speech acts(e.g.,expressives and directives in particular).(2)The innovative tildes convey sound extension,ie.,to compensate for the loss of audio information in online communication and reproduce elongated sounds;pragmatic function,i.e.,to enhance or mitigate the illocutionary forces of speech acts;and entertaining function,i.e.,to make messages informal,vivid,joyful,and interesting.(3)The innovative tildes are pragmalicalized as a result of their semiotic features and politeness motivation of messengers for maintaining rapport and achieving successful online communication.

关键词： innovative uses of tildes online communication politeness pragmatic-alization WeChat messages

Data-driven flatness intelligent representation method of cold rolled strip

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Journal of Iron and Steel Research International 2023年第5期30卷 994-1012页

作者： Yang-huan xu Dong-cheng Wang Bo-wei Duan Hong-min Liu National Engineering Research Center for Equipment and Technology of Cold Rolling Strip Yanshan UniversityQinhuangdao 066004HebeiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an 710032ShaanxiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

A high-accuracy flatness prediction model is the basis for realizing flatness *** flatness is typically reflected as the strain distribution,which is a ***,it is difficult to obtain ideal results if the real flatness is directly used as the output value of the flatness intelligent prediction ***,it is necessary to seek an abstract representation method of real *** this reason,two new intelligent flatness representation models were proposed based on the autoencoder of unsupervised learning theory:the flatness autoencoder representation(FAR)model and the flatness stacked sparse autoencoder representation(FSSAR)*** with the traditional Legendre fourth-order polynomial representation model,the representation accuracies of the FAR and FSSAR models are significantly improved,better representing the flatness defects,like the double tight *** optimal number of bottleneck layer neurons in the FAR and FSSAR models is 5,which means that five basic patterns can accurately represent real *** with the FAR model,the FSSAR model has higher representation accuracy,although the flatness basic pattern is more abstract,and the physical meaning is not clear ***,the accuracy of the FAR model is slightly lower than that of the FSSAR ***,it can automatically learn the flatness basic pattern with a very clear physical meaning for both the theoretical and real flatness,which is an optimal intelligent representation method for flatness.

关键词： Cold rolling flatness Data-driven model Unsupervised learning Representation learning Autoencoder Bottleneck layer

Intelligent representation method of image flatness for cold rolled strip

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Journal of Iron and Steel Research International 2024年第5期31卷 1177-1195页

作者： Yang-huan xu Dong-cheng Wang Hong-min Liu Bo-wei Duan National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710018ShaanxiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina

Real flatness images are the bases for flatness detection based on machine vision of cold rolled *** characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is *** interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be *** this basis,the concept of image flatness is proposed for the first *** image flatness representation(IFAR)model is established on the basis of an autoencoder with a new *** optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation ***,interpretability analysis of the representation factors is carried out,and the difference and physical meaning of the representation factors for image flatness with different categories are *** flatness with new defect morphologies(bilateral quarter waves and large middle waves)that are not present in the original dataset are generated by modifying the representation factors of the no wave ***,the SLD and IFAR models are used to detect and represent all the real flatness images on the test *** average processing time for a single image is 11.42 ms,which is suitable for industrial *** research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： Cold rolled strip Image flatness Location detection Representation learning Bottleneck layer

Origin of beaded tafoni in cliffs of Danxia landscapes,Longhushan Global Geopark, South China

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Journal of Mountain Science 2018年第11期15卷 2398-2408页

作者： GUO Fu-sheng CHEN Liu-qin xu huan LIU Xin State Key Laboratory of Nuclear Resources and Environment East China University of Technology Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals Shandong University of Science and Technology School of Earth Sciences East China University of Technology

The tafoni that develop in sandstone cliffs have attracted the interest of both scientists and the general public. A necklace-like tafone system, referred to here as beaded tafoni, has developed in the prominent cliffs of the Danxia landscapes within the Longhushan Global Geopark in the subtropical zone of South China. This paper presents a new model of the formation of this system of extraordinary beaded tafoni. The cliffs of the Danxia landscapes of the study area are composed of an alluvial conglomerate(i.e.,red beds). These Danxia landscapes have subrounded summits that are covered by vegetation and experience a nearly vertical water flow induced by gravity. Erosion and collapse of the outsized gravels and concentrated pebbles in the red beds give rise to the initial development of the beaded tafoni. The tafoni then become rounded and beaded as a result of reworking and decay by fluvial outwash. During storms, intense water flows run vertically down the cliffs and generate a whirling motion in the ***, the inside walls of the tafoni gradually become wider and smoother. During the late development stage, the beaded tafoni tend to become indistinct or disappear because of the interconnection of the tafoni and subsequent merging with the bedding-controlled cavities.

关键词： Beaded tafoni Alluvial red beds Danxia landscape Longhushan Global Geopark

Stratigraphy and Geochronology of Vertebrate Fossil-Bearing Jurassic Strata from Linglongta,Jianchang County,Western Liaoning,Northeastern China

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1326-1339页

作者： PENG Nan LIU Yongqing KUANG Hongwei JIANG Xiaojun xu huan Institute of Geology Chinese Academy of Geological Sciences School of the Earth Science and Resources China University of Geosciences

Northeastern China contains widely distributed Jurassic terrestrial strata that have yielded many spectacular mammal and pterosaur fossils, in addition to feathered dinosaur fossils and more recent discoveries from Jianchang, particularly from western Liaoning. However, the fossil-bearing stratigraphic succession, regional correlation, and age estimates of the fossils found in Jianchang County and nearby areas have been contentious. Here, we report on the vertebrate fossil-bearing Jurassic stratigraphy from Linglongta, Jianchang County, western Liaoning, including a SHRIMP U-Pb zircon date unambiguously associated with the fossil horizons. The primary goal was to determine the vertebrate fossil-bearing succession. A further aim was to provide age estimations for the fossil-bearing horizon as well as the earliest appearance of feathered dinosaurs, the eutherian-placental clade, and transitional pterosaurs. Field investigations showed that the vertebrate fossil-bearing stratigraphic succession in Jianchang County mainly consists of basal andesites overlain by rhythmic tufts and tuffaceous lacustrine sediments, with the upper intermediate or acidic lavas interbedded with laminated more or less tuffaceous lacustrine deposits. This sequence correlates well with the Middle Jurassic Lanqifl＇iaojishan Formation in northeastern China. Detailed and accurate field observations showed that the well- preserved vertebrate fossils were buried in either the middle or the upper fine-grained laminated lacustrine deposits. Previous and current SHRIMP U-Pb zircon dates provide an age estimation of 161- 159 Myr for the fossil-bearing horizon and vertebrates. This indicates that the earliest appearance of feathered dinosaurs here was more than 159 Myr ago and unquestionably older than Archaeopteryx from Germany, making these the earliest known feathered dinosaurs in the world. Furthermore, the eutherian-placental clade and the known transitional pterosaurs first emerged no later than 161

关键词： Jurassic vertebrates stratigraphy geochronology northeastern China

Synthesis,Crystal Structure and Magnetic Properties of a Novel Copper Inverse-9-metallacrown-3 Complex

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1072-1076页

作者： LIU Guang-Xiang xu huan-Min REN Xiao-Ming Anhui Key Laboratory of Functional Coordination Compounds School of Chemistry and Chemical Engineering Anqing Normal University Anqing 246003 China

The reaction ofphenyl 2-pyridyl ketoxime （PhPyCNOH） with Cu（NO3）2·3H2O has led to a triangular complex Cu3（OH）（PhPyCNO）3（NO3）·NO3·H2O 1 containing the [Cu3（μ2-OH）]5＋ core and possessing the very rare inverse 9-metallacrown-3 motif created by the bridging oximate groups. Crystallographic data for 1： C36H30N8O11CU3, Mr = 941.30, monoclinic, space group C2/c, a = 18.815（9）, b = 33.888（15）, c = 14.307（7） A, β = 118.945（6）°, V= 7983（6） A3, Z = 8, Dc = 1.566 g/cm3, μ = 1.652 mm^-1, F（000） = 3816, R= 0.0644 and wR= 0.1393 for 3468 observed reflections （I〉 2σ（I））. Preliminary variable-temperature magnetic susceptibility studies reveal an antiferromagnetically-coupled system showing antisymmetrie exchange.

关键词： cupric complex crystal structure magnetism