Is Precipitation the Dominant Controlling Factor of High Inorganic Nitrogen Content in the Changjiang River and Its Mouth？   总被引：1，自引：1，他引：0  

沈志良 《中国海洋湖沼学报》2003,21(4):368-376

The main reasons for the high content of inorganic N and its increase by several times in the Changjiang River and its mouth during the last 40 years were analysed in this work. The inorganic N in precipitation in the Changjiang River catchment mainly comes from gaseous loss of fertilizer N, N resulting from the increases of population and livestock, and from high temperature combustions of fossil fuels. N from precipitation is the first N source in the Changjiang River water and the only direct cause of high content of inorganic N in the Changjiang River and its mouth. The lost N in gaseous form and from agriculture non-point sources fertilizer comprised about 60% of annual consumption of fertilizer N in the Changjiang River catchment and were key factors controlling the high content of inorganic N in the Changjiang River mouth. The fate of the N in precipitation and other N sources in the Changjiang River catchment are also discussed in this paper.  相似文献   

成都市冬季重污染日气象条件成因分析及预报     

张波  杨柏生 《成都信息工程学院学报》1992,(3)

本文通过对成都10个重污染日进行天气学分析,将污染浓度与气象要素进行聚类、研究了重污染日形成原因及污染浓度与气象要素的关系。在此基础上,建立了SO_2、TSP日平均浓度分级预报方程。  相似文献   

Automated Separation of Stars and Normal Galaxies Based on Statistical Mixture Modeling with RBF Neural Networks     

Dong-Mei Qin  Ping Guo  Zhan-Yi Hu  Yong-Heng ZhaoNational Laboratory of Pattern Recognition Laboratory  Institute of Automation  Chinese Academy of Sciences  Beijing  dmqin@nlpr.ia.ac.cnDepartment of Computer Sciences  Beijing Normal University  Beijing National Astronomical Observatories  Chinese Academy of Sciences  Beijing 《中国天文和天体物理学报》2003,3(3)

For LAMOST, the largest sky survey program in China, the solution of the problem of automatic discrimination of stars from galaxies by spectra has shown that the results of the PSF test can be significantly refined. However, the problem is made worse when the redshifts of galaxies are not available. We present a new automatic method of star/(normal) galaxy separation, which is based on Statistical Mixture Modeling with Radial Basis Function Neural Networks (SMM-RBFNN). This work is a continuation of our previous one, where active and non-active celestial objects were successfully segregated. By combining the method in this paper and the previous one, stars can now be effectively separated from galaxies and AGNs by their spectra-a major goal of LAMOST, and an indispensable step in any automatic spectrum classification system. In our work, the training set includes standard stellar spectra from Jacoby's spectrum library and simulated galaxy spectra of EO, SO, Sa, Sb types with redshift ranging from 0 to 1  相似文献   

Biogenic silicate accumulation in sediments, Jiaozhou Bay   总被引：1，自引：0，他引：1  

李学刚宋金明  戴纪翠袁华茂李宁  李凤业孙松 《中国海洋湖沼学报》2006,24(3):270-277

1 INTRODUCTION Silicate, or silicic acid (H4SiO4), is a very im- portant nutrient in the ocean. Unlike other major nu- trients such as phosphate and nitrate or ammonium, which are needed by almost all marine plankton, silicate is an essential chemical req…  相似文献   

Observation of, and temporal variations in, solar p-mode multiplet frequency asymmetries at  ℓ= 2      

W. J. Chaplin  Y. Elsworth  G. R. Isaak  B. A. Miller  R. New  S. Thiery  P. Boumier  A. H. Gabriel 《Monthly notices of the Royal Astronomical Society》2003,343(1):343-352

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Some statistical aspects of estimating the local red clump absolute magnitude     

Chris Koen  Fred Lombard 《Monthly notices of the Royal Astronomical Society》2003,343(1):241-248

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A Bayesian approach to discrete object detection in astronomical data sets     

M. P. Hobson  C. McLachlan 《Monthly notices of the Royal Astronomical Society》2003,338(3):765-784

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A Faraday rotation template for the Galactic sky     

Patrick Dineen  Peter Coles 《Monthly notices of the Royal Astronomical Society》2005,362(2):403-410

Using a set of compilations of measurements for extragalactic radio sources, we construct all-sky maps of the Faraday rotation produced by the Galactic magnetic field. In order to generate the maps, we treat the radio source positions as a kind of 'mask' and construct combinations of spherical harmonic modes that are orthogonal on the masked sky. As long as relatively small multipoles are used, the resulting maps are quite stable to changes in the selection criteria for the sources, and show clearly the structure of the local Galactic magnetic field. We also suggest the use of these maps as templates for cosmic microwave background (CMB) foreground analysis, illustrating the idea with a cross-correlation analysis between the Wilkinson Microwave Anisotropy Probe ( WMAP ) data and our maps. We find a significant cross-correlation, indicating the presence of a significant residual contamination.  相似文献   

REVIEWS OF GEOGRAPHIC SOFTWARE     

《The Professional geographer》1987,39(1):85-94

Reviews of geographic software in this article: DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS. ESP GAUSS. CEMODEL S. Damus LIMDEP. William H. Greene MICROSTAT 4.1 OTIS PCIPS. (Personal Computer Image Processing System) . H.J. Meyers and R. Bernstein. REGRESSION ANALYSIS OF TIME SERIES (RATS) SPSS/PC+ URBAN DATA MANAGEMENT SOFTWARE (UDMS)  相似文献   

Extracting star formation histories from medium-resolution galaxy spectra     

H. Mathis  S. Charlot  J. Brinchmann 《Monthly notices of the Royal Astronomical Society》2006,365(2):385-400

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