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Distribution and mapping of temperate savanna in the sandy lands of eastern China

Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG tao duan Kaijie YANG Bin YANG Chunmei WANG Xin TIAN Qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and Environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Coating of microbially produced calcium carbonate onto stone materials

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Science China(Technological Sciences) 2015年第2期58卷 266-272页

作者： ZHU Wen Kun MU tao ZHANG You Kui duan tao LUO Xue Gang Engineering Research Center of Biomass Materials Ministry of Education Southwest University of Science and Technology China Academy of Engineering Physics Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and Technology and Research Center of Laser FusionCAEP

The coatings of microorganism-induced calcium carbonate onto the stone surface carried out by using both of the immersion method and coating method were investigated. Various analysis and testing techniques such as scanning electron micrograph （SEM） and X-ray diffraction （XRD） were used to characterize the deposited mineral layer. The adhesive property, acid re- sistance, frost resistance, light and aging resistance, water adsorption and permeability were investigated in detail. The results showed that both immersion method and coating method could produce calcium carbonate granules with sizes ranging from 1 to 10 pm and form a layer of dense mineralization membrane which is about 50 to 100 pm thick. Immersion method was more efficient than coating method. The large cohesive force between calcium carbonate layer and stone materials could improve the acid rain resistance as well as excellent heat tolerance, frost resistance and light aging resistance. The coating process could not only help the stone materials maintain its original permeability with the aid of calcium carbonate layers but also improve the penetration resistance significantly. Therefore, this type of technology shows a great potential in the protection of stone relics.

关键词： microorganism microbially induced deposited-layer stone materials

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Topology of Knotted Optical Vortices

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Communications in Theoretical Physics 2008年第8期50卷 345-348页

作者： REN Ji-Rong ZHU tao duan Yi-Shi Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

Optical vortices as topological objects exist ubiquitously in *** this paper,by making use of the duan's topological current theory,we investigate the topology in the closed and knotted optical *** topological inner s... 详细信息

关键词： optical vortices knot topology topological current

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DuFNet:Dual Flow Network of Real-Time Semantic Segmentation for Unmanned Driving Application of Internet of Things

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Computer Modeling in Engineering & Sciences 2023年第7期136卷 223-239页

作者： tao duan Yue Liu Jingze Li Zhichao Lian d Qianmu Li School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing210094China School of Cyberspace Security Nanjing University of Science and TechnologyWuxi320200China

The application of unmanned driving in the Internet of Things is one of the concrete manifestations of the application of artificial intelligence *** semantic segmentation can help the unmanned driving system by achieving road accessibility *** segmentation is also a challenging technology for image understanding and scene *** focused on the challenging task of real-time semantic segmentation in this *** this paper,we proposed a novel fast architecture for real-time semantic segmentation named *** from the existing work of Bilateral Segmentation Network(BiSeNet),DuFNet proposes a novel Semantic Information Flow(SIF)structure for context information and a novel Fringe Information Flow(FIF)structure for spatial *** also proposed two kinds of SIF with cascaded and paralleled structures,*** SIF encodes the input stage by stage in the ResNet18 backbone and provides context information for the feature *** from previous stages usually contain rich low-level details but high-level semantics for later *** convolutions embed in Parallel SIF aggregate the corresponding features among different stages and generate a powerful global context representation with less computational *** FIF consists of a pooling layer and an upsampling operator followed by projection convolution *** concise component provides more spatial details for the *** with BiSeNet,our work achieved faster speed and comparable performance with 72.34%mIoU accuracy and 78 FPS on Cityscapes Dataset based on the ResNet18 backbone.

关键词： Real-time semantic segmentation convolutional neural network feature fusion unmanned driving fringe information flow

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Melatonin promotes the development of the secondary hair follicles by regulating circMPP5

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1696-1712页

作者： Xiaogao Diao Lingyun Yao tao duan Jiaxin Qin Liwen He Wei Zhang Department of Animal Nutrition and Feed Science State Key Laboratory of Animal NutritionCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background The quality and yield of cashmere fibre are closely related to the differentiation and development of secondary hair follicles in the skin of cashmere *** higher the density of secondary hair follicles,the higher the quality and yield of cashmere from the *** of secondary hair follicles commences in the embryonic stage of life and is completed 6 months after *** experimental results from our laboratory showed that melatonin(MT)treatment of goat kids after their birth could increase the density of secondary hair follicles and,thus,improve the subsequent yield and quality of *** changes in the secondary hair follicles resulted from increases in levels of antioxidant and expression of anti-apoptotic protein,and from a reduction in *** present study was conducted to explore the molecular mechanism of MT-induced secondary hair follicle differentiation and development by using whole-genome *** MT had no adverse effect on the growth performance of cashmere kids but significantly improved the character of the secondary hair follicles and the quality of cashmere,and this dominant effect continued to the second *** promotes the proliferation of secondary hair follicle cells at an early *** formation of secondary hair follicles in the MT group was earlier than that in the control group in the second *** genome-wide data results involved KEGG analysis of 1044 DEmRNAs,91 DElncRNAs,1054 DEcircRNAs,and 61 DEmiRNAs which revealed that the mitogen-activated protein kinase(MAPK)signaling pathway is involved in the development of secondary hair follicles,with key genes(FGF2,FGF21,FGFR3,MAPK3(ERK1))being up-regulated and *** also found that the circMPP5 could sponged miR-211 and regulate the expression of *** We conclude that MT achieves its effects by regulating the MAPK pathway through the circMPP5 sponged the miR-211,regulating the expression of MAPK3,to induce

关键词： Cashmere MAPK Melatonin miR-211 Secondary hair follicle

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Ablation Mechanism of Carbon/Carbon Composites Modified by HfC–SiC in Two Conditions Under Oxyacetylene Torch

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Journal of Materials Science & Technology 2017年第1期33卷 71-78页

作者： Ke-Zhi Li tao duan Jia-Ping Zhang Ning-Kun Liu Mao-Yan Zhang State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research Center Northwestern Polytechnical University Xi'an 710072 China

C/C-HfC-SiC composites prepared by precursor infiltration and pyrolysis process were ablated by oxyacetylene torch under two different flame conditions. The ablation performance of the composites was investigated in the heat flux of 2.38 MW/m2 （HF-L） and 4.18 MW/m2 （HF-H） for 60 s. The mechanical denudation in 4.18 MW/m2 （HF-H） was higher than that in 2.38 MW/m2 （HF-L）, while the results indicated that the composites had a similar and good ablation property under two different flame conditions. C/C- HfC-SiC composites can adapt the heat flux from 2.38 MW/m2 to 4.18 MW/m2. The Hf02 was not melted completely in the heat flux of 2.38 MW/m2 （HF-L）. So, both Hf02 and Si02 layers acted as an effective barrier to the transfer of heat and oxidative gases into the underlying carbon substrate. SiO2 was severely consumed in 4.18 MW/m2 （HF-H）, where the HfO2 molten layer played a more important role in protecting the inner composite.

关键词： Carbon/carbon composites Corrosion Ablation performance

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Effects of melatonin implantation on carcass characteristics, meat quality and tissue levels of melatonin and prolactin in Inner Mongolian cashmere goats

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Journal of Animal Science and Biotechnology 2019年第4期10卷 1081-1088页

作者： tao duan Ziyuan Wu Huan Zhang Ying Liu Yan Li Wei Zhang State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193People’s Republic of China Beijing Sunlon Livestock Development Company Beijing 100076People’s Republic of China College of Animal Science Zhejiang UniversityHangzhou 310085People’s Republic of China

Background: Implantation of goats with melatonin can induce cashmere growth and significantly increase cashmere production performance. However, the impact of melatonin implantation on the carcass characteristics,meat quality and related hormone levels in muscle and viscera of cashmere goats has not been studied. This experiment was conducted to determine the effects of melatonin implantation of cashmere goats during the nongrowing period on meat quality and related hormone levels in the tissues. It aimed to provide a theoretical basis for the practical application of melatonin in cashmere goat production ***: Melatonin implantation(2 mg/kg live weight) had no influence(P > 0.05) on daily weight gain, carcass weight, dressing percentage, loin muscle area, or the p H, moisture level, crude fat(except for Gluteus muscle) and amino acid content of muscles of cashmere goats. After implantation for 1 month, shear force of Longissimus dorsi and water loss rate of Longissimus dorsi and Biceps femoris of cashmere goats were increased(P 0.05) on the melatonin or prolactin contents of kidney, heart, spleen, liver, Longissimus dorsi, Biceps femoris and Gluteus muscles. Melatonin content of lung tissue was lowered(P < 0.05) and that of prolactin was elevated(P < 0.05) by the melatonin ***: This study has shown little impact of melatonin implantation of cashmere goats on carcass quality. A few meat quality indices i.e., shear force, water loss rate, ∑n-3 PUFA, ∑n-6 PUFA, and crude protein content of Longissimus dorsi;water loss rate, cooking yield and crude protein content of Biceps femoris;ether extract, c

关键词： Carcass characteristics Cashmere goat Meat quality Melatonin

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Regulation of Microstructure of Calcium Carbonate Crystals by Egg White Protein

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Chemical Research in Chinese Universities 2012年第2期28卷 180-185页

作者： ZHU Wen-kun LUO Xue-gang ZHANG Chi duan tao ZHOU Jian School of National Defense Science and Technology Southwest University of Science and TechnologyMianyang 621010P.R.China Engineering Research Center of Biomass Materials of Ministry of Education Southwest University of Science and TechnologyMianyang 621010P.R.China

Crystal growth of calcium carbonate in biological simulation was investigated via egg white protein with different volume fractions,during which calcium carbonate was synthesized by calcium chloride and sodium *** morphology,thermal properties and microstructure of the calcium carbonate micro-to-nanoscale crystals were characterized by scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,Fourier transform infrared spectroscopy（FTIR）,thermogravimetric analysis（TG） and X-ray diffraction（XRD） *** results show that the volume fraction of egg white protein has great influence on the shape,size and morphology of calcium carbonate *** calcium carbonate crystals were the mixtures of calcite-vaterite-like crystals including spherical and rough surface,which are different from that formed in pure *** the increase of egg white protein concentration,the diameter of calcium carbonate crystals changed,the amount of formed spherical calcium carbonate particles decreased and that of vaterite *** results indicate that the coordination and electrostatic interaction between egg white protein and Ca2＋ significantly affect the calcium carbonate crystalization.

关键词： Egg white protein Spherical calcium carbonate Vaterite Calcite

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Study on the chaotic dynamics of the mode-locked fiber ring laser

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 104-108页

作者： GAO Bo WU Ge duan tao HUO Jia-yu TIAN Xiao-jian College of Communication Engineering Jilin University College of Electronic Science and Engineering Jilin University The Northern Institute of Electronic Equipment of China

In this paper, we study the chaotic dynamics of the mode-locked fiber laser by numerical simulation. The structures of the passively mode-locked fiber laser and the actively mode-locked fiber laser are studied by modeling and analysis. By appropriately adjusting the small signal gain of the optical fiber amplifier, we observe the period-doubling bifurcations and route to chaos in the passively mode-locked fiber laser based on nonlinear polarization rotation effect. Chaos in the actively mode-locked erbium-doped fiber laser is obtained by adjusting the elliptic modulus parameter of the active modulator and the intra-cavity length. Simulation results have theoretical significance for the practical application of chaotic soliton communication.

关键词： mode-locked fiber laser period-doubling chaos optical soliton

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Influence of cryogenic thermal cycling treatment on the thermophysical properties of carbon/carbon composites between room temperature and 1900℃

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Journal of Materials Science & Technology 2018年第2期34卷 409-415页

作者： Mao-yan Zhang Ke-zhi Li Xiao-hong Shi Ling-jun Guo Lei Feng tao duan State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Influence of cryogenic thermal cycling treatment （from -120 ℃ to 120 ℃ at 1.3 × 10^-3 Pa） on the thermo- physical properties including thermal conductivity （TC）, thermal diffusivity （TD）, specific heat （SH） and coefficient of thermal expansion （CTE） ranging from room temperature to 1900 ℃ of carbon/carbon （C/C） composites in x-y and z directions were studied. Test results showed that fiber/matrix interracial debonding, fiber pull-out and microcracks occurred after the cryogenic thermal treatment and they increased significantly with the cycle number increasing, while cycled more than 30 times, the space ofmicrodefects reduced obviously due to the accumulation of cyclic thermal stress. TC, TD, SH and CTE of the cryogenic thermal cycling treated C/C composites were first decreased and then increased in both directions （x-y and z directions） with the increase of thermal cycles. A model regarding the heat conduction in cryogenic thermal cycling treated C/C composites was proposed.

关键词： Carbon/carbon composites Cryogenic thermal cycling Thermal conductivity Thermal expansion

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