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Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, li Xiaoying1,2.3, zhang Yong1,2.3, ZHAO Feng1,2.3, GU Xingfa1,3,4, ZHU li1,2.3, WANG Pengxin5 & MIN Xiangjun6 1. state key Laboratory of Remote sensing Science Institute of Remote sensing Application, CAS, Bei- jing 100101, china 2. Graduate university of Chinese Academy of Sciences, Beijing 100039, china 3. The Center for National Spaceborne Demonstration, Beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of information and Electrical engineering, china Agricultural university, Beijing 100083, china 6. china Center for Resource Satellite Data and Application, Beijing 100830, china 1. state key Laboratory of Remote {2. Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate university of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of information and Electrical engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

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Whole-genome resequencing of Hu sheep identifies candidate genes associated with agronomic traits

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Journal of Genetics and Genomics 2024年第8期51卷 866-876页

作者： liming Zhao Lvfeng Yuan Fadi li Xiaoxue {2. Huibin Tian Zongwu Ma Deyin {2. Yukun {2. Yuan Zhao Kai Huang Xiaolong li Jiangbo Cheng Dan Xu Xiaobin yang Kunchao Han Xiuxiu Weng Weimin Wang state key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsEngineering Research Center of Grassland IndustryMinistry of EducationCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouGansu 730020China Lanzhou Veterinary Research Institute Chinese Academy of Agricultural SciencesLanzhouGansu 730046China College of Animal Science and Technology Gansu Agricultural UniversityLanzhouGansu 730070China

The phenotypic diversity resulting from artificial or natural selection of sheep has made a significant contribution to human *** sheep are a local sheep breed unique to china with high reproductive rates and rapid *** selection signatures have been widely used to investigate the genetic mechanisms underlying phenotypic variation in ***,we conduct whole-genome sequencing of 2.7 Hu sheep and compare them with the wild ancestors of domestic sheep(Asiatic mouflon)to investigate the genetic characteristics and selection signatures of Hu *** on six signatures of selection approaches,we detect genomic regions containing genes related to reproduction(BMPR1B,BMP2.PGFS,CYP19,CAMK4,GGT5,and GNAQ),vision(ALDH1A2.SAG,and PDE6B),nervous system(NAV1),and immune response(GPR35,SH2.2.PIK3R3,and HRAS).Association analysis with a population of 12.9 Hu sheep reveals that those missense mutations in the GPR35(GPR35 g.952.51 A>G;GPR35 g.952.96 C>T)and NAV1(NAV1 g.842.6190 C>T;NAV1 g.842.7412.G>A)genes are significantly associated(Plitates further genetic improvement and molecular investigations.

关键词： Hu sheep Whole-genome resequencing Selection signature GPR35 NAV1 Single nucleotide polymorphism

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Solid solution strategy modulated defects engineering of(Cr_(1-x)V_(x))_(2.AlC MAX phase toward superior electromagnetic wave absorption

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Rare Metals 2024年第7期43卷 3205-3219页

作者： Ji-lin Gou Yu-Kai Chang Shu liu Peng-Hui li Ping-Hao Cui Qian-Ku Hu li-Bo Wang Xin zhang Jun-Kai Wang Qi-Xun Xia Ai-guo Zhou School of Materials Science and engineering Henan Polytechnic UniversityJiaozuo 454003China key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China state key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Defects engineering is an effective strategy for manipulating electromagnetic parameters and enhancing electromagnetic wave(EMW)absorption ***,the relationship between them is not clear,especially in solid solution *** this work,a series of(Cr_(1-x)V_(x))_(2.AlC MAX phase solid solutions with layered structure were prepared via tuning the ratio of Cr and V to explore their EMW absorption *** experimental results indicated that the doping of V atoms at the M-site could effectively regulate its impedance matching and EMW absorption properties by introducing appropriate numbers of defects in the crystal,such as twin boundaries,dislocations and lattice *** them,if Cr:V=3:1,Cr_(1.5)V_(0.5)AlC,as radar absorption materials,could reach a strong reflection loss of-51.8 dB at the frequency of 12.8 GHz under an ultra-thin thickness of 1.3 *** reflection loss value could attain-10 dB in a wide frequency range of 2.7-18 GHz and thickness range of 1-5 *** addition,after high temperature and acid-alkali immersion treatment,this sample still had good EMW absorption capability,and the effective absorption bandwidth was enhanced from 2.3 to 2.6 GHz after concentrated acid immersion or 3.1 GHz after concentrated alkali *** work has great reference significance for the research and development of high-performance MAX-based EMW absorption materials in harsh environments.

关键词： MAX phases Solid solution Defects engineering Electromagnetic wave absorption Harsh environments

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Effects of biochar produced from distiller grains on agronomic performances of sorghum(Sorghum bicolor L.) and greenhouse gas emissions from soil

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Pedosphere 2024年第5期34卷 951-959页

作者： Hongjun yang Suyi zhang Jingyu HU Jian{2. HUANG Zonghua AO Xiaoqin WANG Zhe li Xuepin liAO College of Resources and Environment Southwest University National engineering Research Center of Solid-{2. Brewing Luzhou Laojiao Co.Ltd. College of Biomass Science and engineering Sichuan University

Aromatic liquor breweries produce massive distiller grains containing a high percentage of rice husks that necessitate harmless treatment and resource utilization. These husk-rich distiller grains can be pyrolyzed in the Ni-based catalyst system at a relatively low temperature（480?C） into combustible gas,which is used in liquor distillation, and biochar（BDG） with high mineral nutrients and good surface properties. A 3-year field experiment（2.18–2.2.） was established to understand the effects of BDG on sorghum agronomic performances and greenhouse gas emissions from the soil. The results showed that BDG had higher mineral nutrient（N, P, K, and S） contents, larger cation exchange capacity, and better surface structure than those prepared using the traditional method at 400 and 600?C. Compared with sole chemical fertilizer（CF）, the combination of CF and BDG（CF+BDG） increased sorghum nutrient（N, P, and K） uptake, yield, fertilizer use efficiency, and economic benefit. Cumulative CO2.mission from the soil changed little between with and without BDG,indicating the microbial stability of BDG. The effective adsorption of NH3or NH4+by BDG upon N application may reduce N loss through NH3and N2. emissions and increase the efficiency of fertilizer N use. Cumulative CH4emission ranged from 32.45 to 44.86 g ha-1, which could be overlooked as a greenhouse gas in the sorghum field. Moreover, CF+BDG significantly decreased NH3and N2. emissions for the production of each unit of sorghum grains and the CO2.mission from the land for the production of a certain amount of sorghum grains. Therefore, CF+BDG exhibited better agronomic and environmental performances in sorghum cultivation.

关键词： CO2.emission economic benefit environmental performance fertilizer use efficiency N2. emission NH3 emission nutrient uptake yield

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3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

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Nano Research 2024年第4期17卷 2693-2703页

作者： Jie Fu Dong Wang Yan li Xianzheng liu Rui {2. Zhiyuan liu Pengdong liu lijuan {2. Xuefei li Guangwu Wen School of Materials Science and engineering Shandong University of TechnologyZibo 255000China Shandong Si-Nano Materials Technology Co. Ltd.Zibo 255000China

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(liBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2.)with low areal *** sound electrochemical... 详细信息

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(liBs)but are usually achieved at low areal loadings(1.5 mg·cm^(-2.)with low areal *** sound electrochemical performance at high loading requires proportionally higher ion/electron currents and robust structural stability in the thicker ***,we report a three-dimensional(3D)printed silicon-graphene-carbon nanotube(3D-Si/G/C)electrode for simultaneously achieving ultrahigh areal/gravimetric capacities at high mass *** periodically arranged vertical channels and hierarchically porous filaments facilitate sufficient electrolyte infiltration and rapid ion diffusion,and the carbonaceous network provides excellent electron transport properties and mechanical integrity,thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass ***,the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm^(-2. exhibits excellent areal capacity of 12.8 mAh·cm^(-2. and specific capacity of 1007 mAh·g^(-1),***-situ optical microscope and ex-situ scanning electron microscope(SEM)confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture.A 3D printed 3D-Si/G/C-1||3D-liFePO_(4)/G full cell holds excellent cyclic stability(capacity retention rate of 78%after 50 cycles)with an initial Coulombic efficiency(ICE)of 96%.This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density liBs.

关键词： silicon anode areal capacity three-dimensional(3D)printing lithium-ion batteries

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Investigation of stress-induced progressive failure of mine pillars using a Voronoi grain-based breakable block model

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International Journal of Mining Science and Technology 2024年第5期34卷 713-729页

作者： Shili Qiu Shirui zhang Quan Jiang Shaojun li Hao zhang Qiankuan Wang state key Laboratory of Geomechanics and Geotechnical {2. Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China university of Chinese Academy of Sciences Beijing 100049China state key Laboratory of Ocean {2. Shanghai Jiao Tong UniversityShanghai 200240China

The Voronoi grain-based breakable block model(VGBBM)based on the combined finite-discrete element method(FDEM)was proposed to explicitly characterize the failure mechanism and predict the deformation behavior of hard-rock mine *** influence of the microscopic parameters on the macroscopic mechanical behavior was investigated using laboratory-scale *** field-scale pillar models(width-to-height,W/H=1,2.and 3)were calibrated based on the empirically predicted stress-strain curves of Creighton mine *** results indicated that as the W/H ratios increased,the VGBBM effectively predicted the transition from strain-softening to pseudo-ductile behavior in pillars,and explicitly captured the separated rock slabs and the V-shaped damage zones on both sides of pillars and conjugate shear bands in core zones of *** volumetric strain field revealed significant compressional deformation in core zones of *** the peak strains of W/H=1 and 2.pillars were relatively consistent,there were significant differences in the strain energy storage and release mechanism.W/H was the primary factor influencing the deformation and strain energy in the pillar *** friction coefficient of the structural plane was also an important factor affecting the pillar strength and the weakest discontinuity *** fracture surface was controlled by the discontinuity angle and the friction *** study demonstrated the capability of the VGBBM in predicting the strengths and deformation behavior of hard-rock pillars in deep mine design.

关键词： Pillar strength FDEM Voronoi tessellation Spalling Bulking

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On power allocation for a cognitive radio network with hybrid spectrum sharing

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Science china(information Sciences) 2011年第11期54卷 2425-2434页

作者： zhang Jing 1,2.3 & ZHU HongBo 1 1 key Laboratory of Wireless Communications of Jiangsu Province,Nanjing {2. of Posts & Telecommunications,Nanjing 2.0003,china 2.College of Electronic Science & engineering,Nanjing {2. of Posts & Telecommunications,Nanjing 2.0003,china 3 state key Laboratory of Millimeter Waves,Nanjing 2.0096,china 1. key Laboratory of Wireless Communications of Jiangsu Province Nanjing University of Posts & Telecommunications Nanjing 210003 China2. College of Electronic Science & Engineering Nanjing University of Posts & Telecommunications Nanjing 210003 China3. State Key Laboratory of Millimeter Waves Nanjing 210096 China

In this study we propose a hybrid spectrum sharing scheme based on power control by combining Overlay with Underlay schemes,to improve radio spectrum *** the scheme,the secondary users dynamically switch their operational states between Overlay and Underlay according to the spectrum *** the dynamics of the primary network is first modeled with a discrete-state Markov process to find the time fraction of secondary users in the Overlay state and that in the Underlay state,which leads to the capacity model of the hybrid spectrum sharing *** the criterion of maximizing capacity,the power allocation of the cognitive network is researched and the optimum power allocation for secondary users is *** a result,the maximum achievable capacity of the cognitive network is *** are given to prove the analysis *** and simulated results indicate that hybrid spectrum sharing based on power control provides a higher capacity than single Overlay and Underlay systems for the cognitive network,i.e.,hybrid spectrum sharing can further improve radio spectrum efficiency.

关键词： cognitive radio network hybrid spectrum sharing primary network dynamics power allocation achievable capacity

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Soil Fertility Indices of Citrus Orchard Land Along Topographic Gradients in the Three Gorges Area of china

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Pedosphere 2011年第6期21卷 782-792页

作者： WU Dian-Ming YU Yuan-Chun XIA li-Zhong YIN Shi-Xue yang lin-zhang College of Forest Resources and Environment Nanjing Forestry University Nanjing 210037 （China） state key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） College of Environmental Science and engineering Yangzhou University Yangzhou 22500g （China）

In the Three Gorges Area of china, soil erosion and the resultant non-point source pollution and ecological degradation have endangered agricultural ecosystems and fresh water reservoirs. Although efforts have been undertaken to reduce soil and water losses from slope land used for citrus production, information on the effects of management practices on soil ferti{2.ty indices is either {2.mited or nonexistent. This study was conducted to compare the effects of 10 years of various management practices, citrus intercropped with white clover (WC), citrus mulched with straw (SM), citrus intercropped with contour hedgerows (CH), citrus orchard land with impermeable membrane (IM), and citrus intercropped with wheat (Triticum aestivum) and peanut (Arachris hypogaea) (WP), as treatments on soil ferti{2.ty indices with that of the conventional citrus management (CM). Results showed that the soil organic carbon, total and available nitrogen, available potassium, and water-stable aggregate (> 0.2. mm) contents at the 0–5 cm depth were higher for the WC and SM treatments than the CM treatment. There was also spatial variation in soil ferti{2.ty along slopes of the WC and SM treatments. The soil total and available nitrogen, phosphorus, and potassium, and water-stable aggregate (> 0.2. mm) contents at both the 0–5 and 5–2. cm depths were higher for the CH and IM treatments than the CM treatment. The average soil available nitrogen and available potassium contents were higher for the WP treatment than the CM treatment, but the WP treatment had {2.ttle effect on the soil organic carbon, total nitrogen, and water-stable aggregate (> 0.2. mm) contents. These suggested that white clover intercropping and straw mulching were the most effective approaches to improve soil ferti{2.ty in citrus orchard land of the Three Gorges area.

关键词： intercropping slope land soil nutrients soil water-stable aggregates straw mulching

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Oxidation behavior of 4774DD1 Ni-based single-crystal superalloy at 980℃ in air

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china Foundry 2024年第2期21卷 116-124页

作者： Yu Fang Ya-zhou li Qiang yang Qun-gong He Xiu-fang Gong Qian Duan Hai-yang Song Fu Wang Qiong-yuan zhang Hong Zeng state key Laboratory of Long-{2.fe High Temperature Materials Dongfang Turbine Co.Ltd.Deyang 618000SichuanChina state key Laboratory for Manufacturing System {2. School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China

The oxidation behavior of a novel Ni-based single-crystal 4774DD1 superalloy for industrial gas turbine applications was investigated by the isothermal oxidation at 980℃ and discontinuous oxidation weight gain *** phase constitution and morphology of surface oxides and the characteristics of the crosssection oxide film were analyzed by XRD,SEM and *** show that the oxidation kinetics of the 4774DD1 superalloy follows the cubic law,indicating its weak oxidation resistance at this *** the oxidation time increases,the composition of the oxide film evolves as following:One layer consisting of a bottom Al_(2.O_(3)sublayer and an upper(Al_(2.O_(3)+NiO)mixture sublayer after oxidized for 2. ***,two layers composed of an outermost small NiO discontinuous grain layer and an internal layer for 75 *** internal layer is consisted of the bottom Al_(2.O_(3)sublayer,an intermediate narrow CrTaO_(4)sublayer,and an upper(Al_(2.O_(3)+NiO)mixture *** two layers comprising an outermost relative continuous NiO layer with large grain size and an internal layer as the oxidation time increases to 12. *** internal layer is composed of the upper(Al_(2.O_(3)+NiO)mixture sublayer,an intermediate continuous(CrTaO_(4)+NiWO_(4))mixture sublayer,and a bottom Al_(2.O_(3)***,three layers consisting of an outermost(NiAl2._(4)+NiCr2._(4))mixture layer,an intermediate(CrTaO_(4)+NiWO_(4))mixture layer,and a bottom Al_(2.O_(3)layer for 2.0 h.

关键词： nickel-base single crystal superalloy oxidation kinetics oxide film microstructure mechanism

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Enhancing energy storage efficiency in lead-free dielectric ceramics through relaxor and lattice strain engineering

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Journal of Materiomics 2024年第6期10卷 1196-1205页

作者： Xuetian Gong Chao zhang Dong Su Wenrong Xiao Fangjie Cen Ying yang Sheng{2.n Jiang Jing Wang Kanghua {2. Guangzu zhang School of Integrated Circuits Engineering Research Center for Functional Ceramics MOE and Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhanHubei430074China College of Chemnistry and Materials Science Hebei UniversityBaodingHebei071002China key Lab of Functional Materials for Electronic information(B) Ministry of EducationWuhanHubei430074China

Dielectric capacitors with high power density and fast charge-discharge speed play an essential role in the development of pulsed power *** increased demands for miniaturization and practicality of pulsed power equipment also necessitate the development of dielectric materials that possess high energy density while maintaining ultrahigh efficiency(η).In particular,ultrahigh efficiency signifies minimal energy loss,which is essential for practical applications but challenging to effectively ***,we demonstrate a strategy of incorporating heterovalent elements into Ba(Zr_(0.1)Ti_(0.9))O_(3),which contributes to achieving relaxor ferroelectric ceramics and reducing lattice strain,thereby improving the comprehensive energy storage ***,optimal energy storage performance is attained in 0.85Ba(Zr_(0.1)Ti_(0.9))O_(3)-0.15Bi(Zn_(2.3)Ta_(1/3))O_(3)(BZT-0.15BiZnTa),with an ultrahighηof 97.37%at 440 kV/cm(an advanced level in the lead-free ceramics)and an excellent recoverable energy storage density(Wrec)of 3.74 J/cm^(3).Notably,the BZT-0.15BiZnTa ceramics also exhibit exceptional temperature stability,maintaining fluctuations in Wrec within∼10%andηconsistently exceeding 90% across the wide temperature range of−55℃ to 160℃,and under a high electric field of 2.0 kV/*** these features demonstrate that the relaxor and lattice strain engineering strategies have been successful in achieving high-performance lead-free ceramics,paving the way for designing high-efficiency dielectric capacitors with a wide temperature range.

关键词： Energy storage Relaxor ferroelectrics Lead-free ceramics Lattice strain engineering

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