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range formula based on angle of dispersion and nozzle configuration from an impact sprinkler

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International Journal of Agricultural and Biological Engineering 2019年第5期12卷 97-105页

作者： Yue Jiang Zakaria Issaka Hong Li Pan Tang Chao Chen Research Centre of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China Department of Agricultural Engineering Tamale Technical UniversityNorthern RegionTamaleGhana

Jet breakup and dispersion from impact sprinkler are mainly influenced by the configurations of nozzle and dispersion device.Based on the structure,different types of nozzles were designed and tested with a pointed tip dispersion device under low pressure conditions.Experiments were performed using High-Speed Photographic technique,and Matlab computation program was established and applied to determine the initial jet breakup length and angle of dispersion from the nozzles.The sprinkler range decreased with the increase in diameter of nozzle,and the largest range of 15.1 m was produced from sprinkler with 6 mm nozzle size under a pressure of 150 kPa.The angle of dispersion decreased with the increase of jet velocity,the spray coverage from sprinkler with 6 mm nozzle size was 1478 mm under 150 kPa,and was not statistically different when the pressure was increased.A new range formula was established for sprinkler with dispersion device through curve fitting of the parameters of initial jet breakup length,angle of dispersion,nozzle size and working pressure.The new formula was reliable for calculating range with a relative error less than 3%.Since the formula is based on the angle of dispersion,it could be useful to estimate uniformity of water distribution in sprinkler irrigated fields.

关键词： fixed dispersion device range jet breakup angle of dispersion spray coverage impact sprinkler

range inclusion of operators on non-archimedean Banach space

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Science China Mathematics 2010年第12期53卷 3215-3224页

作者： WANG PengHui 1 & ZHANG Xu 2,3 1 School of Mathematics, Shandong University, Jinan 250100, China 2 Key Laboratory of Systems and Control, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China 3 School of Mathematics, Sichuan University, Chengdu 610064, China School of Mathematics Shandong University Jinan China Key Laboratory of Systems and Control Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China School of Mathematics Sichuan University Chengdu China

In this paper, we establish some range inclusion theorems for non-archimedean Banach spaces over general valued fields. These theorems provide close relationship among range inclusion, majorization and factorization for bounded linear operators. It is found that these results depend strongly on a continuous extension property, which is always true in the classical archimedean case, but may fail to hold for the non-archimedean setting. Several counterexamples are given to show that our results are sharp in some sense.

关键词： range inclusion majorization factorization non-archimedean Banach space continuous extension property

Research on indoor experimentation of range SAL imaging system

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Science China(Technological Sciences) 2009年第10期52卷 3098-3104页

作者： GUO Liang XING MengDao ZHANG Long TANG Yu BAO Zheng State Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China Xi’an Polytechnic University Xi’an 710048China

By means of advantages of both SAR and lidar, the combination of the techniques of (inverse) synthetic aperture and lidar makes it possible to obtain high resolution 2-D image. In this paper, an indoor experimental system of inverse synthetic aperture lidar imaging is given and a processing approach is presented. The given system is in the mode of lidar system with separated receiver and transmitter, which can effectively eliminate the jamming from the lens or/and the intersection between two optic fibers. Based on the reference channel techniques, a method for the compensation of nonlinear frequency in the time domain is presented, which can solve the problem of nonlinear frequency efficiently. Then, with the mature inverse synthetic aperture algorithm, an image of inverse synthetic aperture lidar can be obtained, which is the first attempt in China. Finally, experimental results confirm the validity of the presented method and the feasibility of the experimental system.

关键词： idar synthetic aperture range profile phase error imaging of rotating objects

Variation in winter daily range area of red deer(Cervus elaphus xanthopygus) based on DNA extracted from fecal samples

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Journal of Forestry Research 2019年第5期30卷 1951-1958页

作者： Miao Yang Yue Sun Wei Qi Zhang Hongyi Yuan Minghai Zhang College of Wildlife Resources Northeast Forestry University

With environmental change and increased human activity,wild red deer(Cervus elaphus xanthopygus)populations and habitat area continue to decrease.Red deer is a main prey species of Amur tiger(Panthera tigris altaica).Factors affecting red deer winter home range in the Wanda montains of northeast China are not well understood.In this study,we aimed to better document red deer daily ranges to support conservation of red deer.A second objective was to develop a practical research method combining macro-and micro-technology for home range research on a variety of rare or endangered wild species.We collected 105 fresh fecal samples of red deer in three different periods during winter from December 2012 to March 2013 in the Wandashan region,Heilongjiang Province,China.Individual and sex identities were analyzed based on fecal DNA using microsatellite DNA.We used samples from deer farms for correction and validation of our identifications from field samples.We used a combination of molecular scatology,3S techniques(GPS),and direct observation to estimate winter daily range areas.Based on eleven microsatellite loci,we identified 18 individuals,10 females and 8 males,with a correction factor of 1.00 and sex ratio of 1:0.8.The mean(±SE)number of alleles was 5.1±0.41,and mean polymorphism information content was 0.63±0.03.Expected heterozygosity ranged from 0.46 to 0.81,with a mean of 0.69±0.03,and mean observed heterozygosity was 0.73±0.07.Sizes of mean daily ranges were 26.1±1.1 ha in December,89.3±1.6 ha in January,and 67.5±1.9 ha in March,indicating the following trend for daily range area:middle winter>late winter>early winter.Mean daily range area was insignificantly larger for males than for females.Estimated winter daily ranges were similar to those reported for Europe.Our combination of macro-and micro-technology proved useful for estimating winter home range areas of red deer.

关键词： Daily range Molecular scatology Red deer Temporal scale Winter

Assessment of Tidal range Energy Resources Based on Flux Conservation in Jiantiao Bay, China

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Journal of Ocean University of China 2017年第6期16卷 1090-1096页

作者： DU Min WU He YU Huaming LV Ting LI Jiangyu YU Yujun Department of Mechanics Tianjin University Tianjin 300350 P. R. China National Ocean Technology Center Tianjin 300112 P. R. China College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao 266100 P. R. China Key Laboratory of Physical Oceanography the Ministry of Education Qingdao 266003 P. R. China

La Rance Tidal range Power Station in France and Jiangxia Tidal range Power Station in China have been both long-term successful commercialized operations as kind of role models for public at large for more than 40 years. The Sihwa Lake Tidal range Power Station in South Korea has also developed to be the largest marine renewable power station with its installed capacity 254 MW since 2010. These practical applications prove that the tidal range energy as one kind of marine renewable energy exploitation and utilization technology is becoming more and more mature and it is used more and more widely. However, the assessment of the tidal range energy resources is not well developed nowadays. This paper summarizes the main problems in tidal range power resource assessment, gives a brief introduction to tidal potential energy theory, and then we present an analyzed and estimated method based on the tide numerical modeling. The technical characteristics and applicability of these two approaches are compared with each other. Furthermore, based on the theory of tidal range energy generation combined with flux conservation, this paper proposes a new assessment method that include a series of evaluation parameters and it can be easily operated to calculate the tidal range energy of the sea. Finally, this method is applied on assessment of the tidal range power energy of the Jiantiao Harbor in Zhejiang Province, China for demonstration and examination.

关键词： tidal range energy numerical modeling flux conservation resource assessment

New Fractal Evidence of Pacific Plate Subduction in the Late Mesozoic, Great Xing’an range, Northeast China

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Journal of Earth Science 2019年第5期30卷 1031-1040页

作者： Pingping Zhu Qiuming Cheng Guoxiong Chen School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

Late Mesozoic granitoids are widespread in the Great Xing’an range(GXR), which is part of a large igneous province in eastern China. The geodynamic setting of the Late Mesozoic granitoids is still debated, and there have been two dominant models proposed, subduction and thermal erosion. This study discusses the geodynamic mechanisms from a new perspective on ages of the granitoids and fractal dimensions of their shape. Our results show that granitoids become gradually older from South GXR to North GXR to Erguna Block(EB) in the Jurassic, and opposite in the Cretaceous. The fractal dimensions of the Perimeter-area model(DAP) exhibit the same features. The values of DAP are smaller from South GXR(0.673 1) to North GXR(0.628 0) to EB(0.607 9) in the Jurassic, and larger from South GXR(0.609 6) to North GXR(0.630 2) to EB(0.639 9) in the Cretaceous. This implies that the geometrical irregularities of the granitoids are shaped by subduction rather than thermal erosion. These spatial variations could be best explained by the subduction of the Pacific Plate and consequent granitoid magmatism in the Late Mesozoic, thus providing a new fractal evidence for Pacific Plate subduction mechanism and opening a new possibility method for studing plate movement.

关键词： granitoids Late Mesozoic fractal dimension Pacific subduction Great Xing’an range Northeast China geochemistry mathematical geology

Vegetation-environment relationship in Pinus wallichiana forests of the Swat Hindukush range of Pakistan

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Journal of Forestry Research 2020年第1期31卷 185-195页

作者： Inayat Ur Rahman Nasrullah Khan Kishwar Ali Siraj Ahmad Laboratory of Plant Ecology and Dendrochronology Department of BotanyUniversity of Malakand

Understanding the influence of environmental variables on the spatial distribution of ecological communities is essential to predict the response of vegetation to various environmental drivers.Ecological theory suggests that multiple environmental factors shape local species assemblages and should influence the various components of community structure and composition in different ways.This study aimed to classify Pinus wallichiana dominated forests in the Swat Hindukush range mountains to understand the relative influence of multiple environmental filters on its composition and structure.These forests represent the most typical of the species distribution in northern Pakistan and were not subjected to any phytosociological study.For this purpose,thirty forest stands,spanning a wide range of physical habitats were sampled using 10910 m plots and the importance value index was calculated.The floristic and environmental data were subjected to Ward’s agglomerative cluster analysis for objective classification and ordinated with NMS ordination for pattern description and testing the vegetation–environmental relationships.Three floristically and ecologically distinct communities were recognized along the topographic gradient(elevation,r=0.377;slope,r=0.5548)coupled with soil physical(clay,r=0.2782;silt,r=0.3225)and chemical properties(pH,r=0.4975;lime,r=3982).An elevation gradient of 100 m separated the low(Pinus wallichiana–Quercus dilatata community)and middle elevations forest stands(P.wallichiana pure population)from the highland population type(Pinus wallichiana–Cedrus deodara community).The floristics and structure of these forest types respond directly or indirectly to topographic and soil variables which were evidenced from the floristic composition,species richness,and community physiognomy.These characteristics of the communities changed from heterogenous,dense stands to sparsely dispersed conifers,broadleaved-evergreen,and deciduous vegetation types along the environmental gradients.We concluded that severa

关键词： Blue pine forests Classi cation ordination Ecological gradient Hindukush range mountains Species composition

Tunable range Interactions and Multi-Roton Excitations for Bosons in a Bose-Fermi Mixture with Optical Lattices

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Communications in Theoretical Physics 2019年第7期71卷 869-875页

作者：冯超陈宇 Institute for Advanced Study Tsinghua UniversityBeijing 100084China Department of Physics Capital Normal UniversityBeijing 100048China

In this article,we discuss a method to control the long-range interactions between bosons in a threedimensional Bose-Fermi mixture with the help of optical lattices on fermions.We find the range and the peaked momentum of the fermion-mediated interactions can be tuned by the optical lattice depth and the fermion density.If the fermion density is close to half-filling,roton excitations can be generated with weak Bose-Fermi interactions.Further,if the fermions are not exact at half-filling,multi-roton structure may emerge,implying competing density orders.Therefore,tuning the lattice depth and the fermion density in a Bose-Fermi mixture serves as an effective way to control the interaction range and resonant momentum between bosons.

关键词： Bose-Fermi mixture multi-roton tunable range interaction

Origin and evolution of ore-forming fluid for the Gaosongshan gold deposit, Lesser Xing’an range:Evidence from fluid inclusions,H-O-S-Pb isotopes

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Geoscience Frontiers 2019年第5期10卷 1961-1980页

作者： Yang Liu Jinggui Sun Jilong Han Liang Ren Alei Gu Keqiang Zhao Changshen Wang College of Earth Science Jilin UniversityChangchun 130061China Tianjin Center of Geological Survey China Geological SurveyTianjin 300170China Geophysical and Geochemical Prospecting Academy Chinese Academy of Geological SciencesLangfang 065000China Team 707 Heilongjiang Bureau of Geological Exploration for Nonferrous MetalsSuihua 152000China

Epithermal gold deposits are typical precious metal deposits related to volcanic and subvolcanic magmatism.Due to the lack of direct geological and petrographic evidences,the origin of the ore-forming fluid is deduced from the spatial diagenesis-mineralization relationship,chronological data,physicochemical characteristics of mineral fluid inclusions,mineral or rock elements and isotopic geochemical characteristics.By objectively examining this scientific problem via a geological field survey and petrographic analysis of the Gaosongshan epithermal gold deposit,we recently discovered and verified the following points:(1) Pyrite-bearing spherical quartz aggregates (PSQA) occur in the rhyolitic porphyry;(2) the mineralization is structurally dominated by WNW- and ENE-trending systems and occurs mostly in hydrothermal breccias and pyrite-quartz veins,and the ore types are mainly hematite-crusted quartz,hydrothermal breccia,massive pyrite-quartz,etc.;(3) the alteration types consist of prevalent silicification,sericitization,propylitization and carbonation,with local adularization and illitization.The ore minerals are mainly pyrite,primary hematite,native gold,and electrum,with lesser amounts of chalcopyrite,magnetite,sphalerite,and galena,indicating a characteristic epithermal low-sulfidation deposit.The ore-forming fluid may have been primarily derived from magmatic fluid exsolved from a crystallizing rhyolitic porphyry magma.Further zircon U-Pb geochronology,fluid inclusion,physicochemical and isotopic geochemical analyses revealed that (1) rhyolitic porphyry magmatism occurred at 104.6 ± 1.0 Ma,whereas the crystallization of the PSQA occurred at 100.8 ± 2.1 Ma;(2) the hydrothermal fluid of the pre-ore stage was an exsolved CO2-bearing H2O-NaCl magmatic fluid that produced inclusions mainly composed of pure vapor (PV),vapor-rich (WV) and liquid-rich (WL) inclusions with a small number of melt-(M) and solid-bearing (S) inclusions;mineralization-stage quartz contains WL and rare PV,WV and pure liquid (PL) inclusions

关键词： Fluid inclusions H-O-S-Pb isotopes Zircon U-Pb dating Gaosongshan gold deposit Lesser Xing'an range Northeast China