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Chinese Science Bulletin 2012年第1期57卷 111-118页

作者： xu guanghui WU FeiXiang Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

The Ginglymodi are a group of ray-finned fishes that make up one of three major subdivisions of the infraclass ***- tant ginglymodians are represented by gars,which inhabit freshwater environments of North and Central America and ***, we report the discovery of well-preserved fossils of a new ginglymodian,Kyphosichthys grandei *** ***.,from the Middle Triassic(Anisian)marine deposits(Guanling Formation)in Luoping,eastern Yunnan Province,*** discovery documents the first known fossil record of highly deep-bodied ginglymodians,adding new information on the early morphological diversity of this *** studies of functional morphology of extant deep-bodied fishes indicate that Kyphosichthys is not a fast swim- mer but has a good performance in precise maneuvering,representing a morphological adaptation to structurally complex habitats (*** macrophyte beds,rocky areas,or coral reefs),which differs from the other members of this group.A cladistic analysis with the new fish taxon included supports the hypothesis that the Ginglymodi are more closely related to the Halecomorphi than to the *** by Felberia,Kyphosichthys,and Dapedium,a highly deep and short fish body type has inde- pendently evolved at least three times in the stem-group neopterygians,ginglymodians,and basal teleosts within the lower neop- terygians of the Triassic.

关键词：中三叠世鳍鱼类云南省系统发育中国化石记录形态多样性游泳运动员

From 0D to 3D:Hierarchical structured high-performance free-standing silicon anodes based on binder-induced topological network architecture

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Journal of Energy Chemistry 2024年第6期93卷 16-23,I0002页

作者： Yihong Tong Ruicheng Cao guanghui xu Yifeng Xia Hongyuan xu Hong Jin Hui xu Xi’an Jiaotong University Suzhou Academy Suzhou 215123JiangsuChina Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123JiangsuChina

Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely ***,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is ***,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking *** which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of *** from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical ***,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization ***,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.

关键词： Topological network Self-stabilization Flexibility Free-standing Silicon anode

Identification and fine mapping of quantitative trait loci for the number of vascular bundle in maize stem

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Journal of Integrative Plant Biology 2016年第1期58卷 81-90页

作者： Cheng Huang Qiuyue Chen guanghui xu Dingyi xu Jinge Tian Feng Tian Department of Plant Genetics and Breeding National Maize Improvement Center of China China Agricultural University

Studies that investigated the genetic basis of source and sink related traits have been widely ***, the vascular system that links source and sink received much less attention. When maize was domesticated from its wild ancestor, teosinte, the external morphology has changed dramatically; however, less is known for the internal anatomy changes. In this study, using a large maize-teosinte experimental population, we performed a high-resolution quantitative trait locus（QTL） mapping for the number of vascular bundle in the uppermost internode of maize *** results showed that vascular bundle number is dominated by a large number of small-effect QTLs, in which a total of 16 QTLs that jointly accounts for 52.2% of phenotypic variation were detected, with no single QTL explaining more than 6% of variation. Different from QTLs for typical domestication traits, QTLs for vascular bundle number might not be under directional selection following *** Near Isogenic Lines（NILs） developed from heterogeneous inbred family（HIF）, we further validated the effect of one QTL qVb9-2 on chromosome 9 and fine mapped the QTL to a 1.8-Mb physical region. This study provides important insights for the genetic architecture of vascular bundle number in maize stem and sets basis for cloning of qVb9-2.

关键词： Fine-mapping genetic architecture maize quantitativetrait locus vascular bundle number

Fusion of Infrared and Visible Images Based on Infrared Object Extraction

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Chinese Journal of Electronics 2021年第2期30卷 339-348页

作者： RONG Chuanzhen LIU Gaohang PING Zhuolin JIA Yongxing YUE Zhenjun xu guanghui Communications Engineering College Army Engineering University of PLA Qingyang Detachment of Armed Police

The ideal fused results of infrared and visible images, should contain the important infrared objects, and preserve the visible textural detail information as much as possible. The fused images are more consistent with human visual perception effect. For this purpose, a novel infrared and visible image fusion framework is proposed. Under the guidance of the model, the source images are decomposed into large-scale edge, small-scale textural detail and coarse-scale base level information. Among which, the large-scale edge information contains the main infrared features, on this basis, the infrared image is further segmented into the object, transition and background regions by OTSU multi-threshold segmentation algorithm. In the end, the fused weights for the decomposed sub-information are determined by the segmented results, so that, the infrared object information can be effectively injected into the fused image, and the important visible textural detail information can be preserved as much as possible in the fused image. Experimental results show that, the proposed method can not only highlight the infrared objects, but also preserve the visual information in the visible image as much as possible. The fused results are superior to the commonly used representative fusion methods, both in subjective perception and objective evaluation.

关键词： infrared object extraction small-scale textural detail information feature extraction human visual perception effect OTSU multithreshold segmentation algorithm subjective perception image fusion coarse-scale base level information large-scale edge information objective evaluation infrared-visible image fusion visual information source images visible textural detail information visual perception image segmentation image texture infrared imaging background regions infrared image segmentation

Carbon nanotubes for supercapacitors:Consideration of cost and chemical vapor deposition techniques

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Journal of Natural Gas Chemistry 2012年第3期21卷 233-240页

作者： Chao Zheng Weizhong Qian Chaojie Cui guanghui xu Mengqiang Zhao Guili Tian Fei Wei Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

In this topic, we first discussed the requirement and performance of supercapacitors using carbon nanotubes （CNTs） as the electrode, including specific surface area, purity and cost. Then we reviewed the preparation technique of single wailed CNTs （SWNTs） in relatively large scale by chemical vapor deposition method. Its catalysis on the decomposition of methane and other carbon source, the reactor type and the process control strategies were discussed. Special focus was concentrated on how to increase the yield, selectivity, and purity of SWNTs and how to inhibit the formation of impurities, including amorphous carbon, multiwalled CNTs and the carbon encapsulated metal particles, since these impurities seriously influenced the performance of SWNTs in supercapacitors. Wish it be helpful to further decrease its product cost and for the commercial use in supercapacitors.

关键词： supercapacitor carbon nanotubes: chemical vapor deposition catalysis methane

Spatial Distribution and Risk Assessment of Heavy Metals in Paddy Soils of Yongshuyu Irrigation Area from Songhua River Basin,Northeast China

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Chinese Geographical Science 2018年第5期28卷 797-809页

作者： CUI Zhengwu WANG Yang ZHAO Na YU Rui xu guanghui YU Yong Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China Jilin Provincal Government Investment Fund Management Co. LTD. Changehun 130000 China

There is an increasing concern for potentially hazardous metals pollution, which can threaten crops production and human health. In this study, the spatial distribution and environmental risks of eight heavy metals in surface soil samples collected from the paddy fields in Yongshuyu irrigation area, Northeast China were investigated. The mean concentrations of Pb, Cr, Cu, Ni, Zn, Cd, Hg and As were 34.6 ± 4.67, 82.8 ± 9.51, 17.3 ± 4.09, 21.2 ± 12.0, 88.6 ± 17.9, 0.18 ± 0.15, 0.22 ± 0.07 and 8.77 ± 2.47 mg/kg, respectively, which were slightly higher than their corresponding background values of Jilin Province, indicating enrichment of these metals in the paddy soils, especially for Ni, Cd and Hg. The spatial distribution of heavy metals was closely correlated with local anthropogenic activities, such as agricultural production, mining and transportation. The hot-spot areas of As and Cd were mainly concentrated in the up-midstream where were associated with agricultural activities. Cr and Cu showed similar spatial distributions with hot-spot areas distributed the whole irrigation area uniformly. Ni was mainly distributed in the downstream where Ni quarries concentrated, while the spatial distribution patterns of Hg was mainly located in the upstream and downstream where the soil was significantly influenced by irrigation and coal mining emission. The spatial distributions of Pb and Zn were mainly concentrated along the highway side. The pollution levels of Yongshuyu irrigation area were estimated through index of geo-accumulation(Igeo), Nemerow integrated pollution index(NIPI) and potential ecological risk index(PERI). The results showed that Cd and Hg were the main pollutants in the study area. Health risk assessment results indicated that children were in higher non-carcinogenic and carcinogenic risks than adults with the carcinogenic metal of As. Ingestion was the main exposure pathway to non-carcinogenic and carcinogenic risk for both adults and children. Princip

关键词： spatial distribution heavy metals paddy soil risk assessment source identification Songhua River Basin

The pioneer of intelligent construction—An overview of the development of intelligent compaction

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Journal of Road Engineering 2022年第4期2卷 348-356页

作者： guanghui xu George K.Chang Dongsheng Wang Antonio G.Correia Soheil Nazarian International Society for Intelligent Construction OkemosMichigan 48864USA

As the pioneer in the intelligent construction technologies(ICT)of transportation infrastructure,intelligent compaction(IC)has been applied in the infrastructure construction of various *** is currently the technology that best reflects the intelligence of engineering *** article overviews the latest developments and trends in ***,the basic meaning of ICT is defined based on the essential characteristics of intelligent construction of transportation infrastructure,“perception,analysis,decision-making,execution”(PADE).The concept of intelligent compaction technology classification is also *** PADE requirements that intelligent compaction should meet are ***,according to the sequence of“perception,analysis,decision-making,execution,”the workflow and key technologies of intelligent compaction are analyzed,and the mechanism of using the response of the roller to solve the modulus is given and *** this basis,The IC feasibility test methods,including compaction degree,compaction stability,and compaction uniformity,are briefly *** implementation scheme of feedback control is ***,the use of artificial neural networks(ANN),hybrid expert systems,and reinforcement learning in intelligent compaction are briefly ***,several extended applications of intelligent compaction are expounded,including the development ideas of intelligent road rollers and the role of intelligent compaction in virtual construction,the layer-specific mechanical parameters of fillers,etc.

关键词： Intelligent construction Intelligent compaction Perception Learning Analysis Decision-making

Binder-Free Activated Carbon/Carbon Nanotube Paper Electrodes for Use in Supercapacitors

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Nano Research 2011年第9期4卷 870-881页

作者： guanghui xu Chao Zheng Qiang Zhang Jiaqi Huang Mengqiang Zhao Jingqi Nie Xianghua Wang Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Beijing 100084 China CNGC Wuzhou Engineering Design and Research Institute Beijing 100053 China

Novel inexpensive, light, flexible, and even rollup or wearable devices are required for multi-functional portable electronics and developing new versatile and flexible electrode materials as alternatives to the materials used in contemporary batteries and supercapacitors is a key challenge. Here, binder-free activated carbon （AC）/carbon nanotube （CNT） paper electrodes for use in advanced supercapacitors have been fabricated based on low-cost, industrial-grade aligned CNTs. By a two-step shearing strategy, aligned CNTs were dispersed into individual long CNTs, and then 90 wt%-99 wt% of AC powder was incorporated into the CNT pulp and the AC/CNT paper electrode was fabricated by deposition on a filter. The specific capacity, rate performance, and power density of the AC/CNT paper electrode were better than the corresponding values for an AC/acetylene black electrode. The capacity reached a maximum value of 267.6 F/g with a CNT loading of 5 wt%, and the energy density and power density were 22.5 W.h/kg and 7.3 kW/kg at a high current density of 20 A/g. The AC/CNT paper electrode also showed a good cycle performance, with 97.5% of the original capacity retained after 5000 cycles at a scan rate of 200 mV/s. This method affords not only a promising paper-like nanocomposite for use in low-cost and flexible supercapacitors, but also a general way of fabricating multi-functional paper-like CNT-based nanocomposites for use in devices such as flexible lithium ion batteries and solar cells.

关键词： Supercapacitor flexible energy storage carbon nanotube activated carbon

New species of Saurichthys(Actinopterygii:Saurichthyidae)from Middle Triassic(Anisian)of Yunnan Province,China

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 440-450页

作者： WU Feixiang SUN Yuanlin HAO Weicheng JIANG Dayong xu guanghui SUN Zuoyu Andrea TINTORI Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871 China Dipartimento di Scienze della Terra Universita degli Studi di Milano Via Mangiagalll34 20133 Milano Italy

Saurichthys dawaziensis sp. nov., from the third member of the Gejiu Formation （Anisian of Middle Triassic） in the vicinity of Luoping, Yunnan Province, is a small to mediumsized saurichthyid fish. It is characterized by the efferent pseudobranchial arteries penetrating on the parasphenoid and the mandible sensory canal with a branch in the angular. The new species is more derived than the Lower Triassic species in having a relatively narrow postorbital region, short preopercular, single ossification of the sclerotic ring, small haemal arches between the pelvic fins and the anal fin without ossified spines, and in the absence of quadratojugal. It is more primitive than the Middle and Upper Triassic Saurichthys in having fringing fulcra and numerous segments in the unpaired fins, and the presence of both prae- and post-zygapophyses in the neural arches. Some anatomic changes related to the vertebral column and unpaired fins of the genus are also discussed.

关键词： Actinopterygian fishes Saurichthyidae Saurichthys Middle Triassic Yunnan

Large scale production of carbon nanotube arrays on the sphere surface from liquefied petroleum gas at low cost

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Chinese Science Bulletin 2007年第21期52卷 2896-2902页

作者： ZHANG Qiang HUANG JiaQi WEI Fei xu guanghui WANG Yao QIAN WeiZhong WANG DeZheng Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering TsinghuaUniversity Beijing 100084 China

Liquefied petroleum gas (LPG), a cheap industrial material, is used as carbon source to produce carbon nanotube (CNT) arrays on ceramic spherical surface on a large scale in the floating catalyst process. The ceramic spheres provide huge surface area and good mobility, leading to the mass production of CNT arrays continuously. The arrays obtained from the surface are of good alignment, and the purity is as high as 97.5%. With the decrease of the growth temperature, CNTs in the array form with small-diameter of about 13 nm can be obtained. Therefore, with the industrial fuel as carbon source and the ceramic sphere as substrate, CNT arrays can easily be produced on large scale at low cost.

关键词：液化气生产量成本碳纳米管阵列