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   

Chandra and RXTE spectroscopy of the Galactic microquasar XTE J1550−564 in outburst     

J. M. Miller  H. L. Marshall  R. Wijnands †  T. Di Matteo  D. W. Fox  J. Kommers  D. Pooley  T. Belloni  J. Casares  P. A. Charles  A. C. Fabian  M. van der Klis  W. H. G. Lewin 《Monthly notices of the Royal Astronomical Society》2003,338(1):7-13

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Development-Conservation Dilemma in the NilgiriMountains of South India     

DharmalingamVENUGOPAL 《山地科学学报》2004,1(1):74-80

The Nilgiri Mountains of south India is considered unique by anthropologists, geologists, climatologists, botanists as well as tourists. It has remained a subject of constant study and research over the last two centuries. Man-nature balance had continued undisturbed in the Nilgiris for thousands of years until the early 19th century when it became a British colony attracting, in due course, various developmental activities. Subsequently, the Nilgiris and its popular hill stations emerged as favourite places for the British population in India for rest and recuperation, game and for raising commercial plantations. In the process, the traditional indigenous crops were replaced by “English“ vegetables and the natural forests gave way to commercial plantations of coffee, tea and other exotic species of trees.  相似文献   

A search for the optical and near-infrared counterpart of the accreting millisecond X-ray pulsar XTE J1751−305     

P. G. Jonker  G. Nelemans  Z. Wang  A. K. H. Kong  D. Chakrabarty  M. Garcia  P. J. Groot  M. van der Klis  T. Kerr  B. Mobasher  M. Sullivan  T. Augusteijn  B. W. Stappers  P. Challis  R. P. Kirshner  J. Hjorth  A. Delsanti 《Monthly notices of the Royal Astronomical Society》2003,344(1):201-206

We have obtained optical and near-infrared images of the field of the accreting millisecond X-ray pulsar XTE J1751−305. There are no stars in the 0.7-arcsec error circle (0.7 arcsec is the overall uncertainty arising from tying the optical and X-ray images and from the intrinsic uncertainty in the Chandra X-ray astrometric solution). We derive limiting magnitudes for the counterpart of   R > 23.1, I > 21.6, Z > 20.6, J > 19.6  and   K > 19.2  . We compare these upper limits with the magnitudes one would expect for simple models for the possible donor stars and the accretion disc subject to the reddening observed in X-rays for XTE J1751−305 and when put at the distance of the Galactic Centre (8.5 kpc). We conclude that our non-detection does not constrain any of the models for the accretion disc or possible donor stars. Deep, near-infrared images obtained during quiescence will, however, constrain possible models for the donor stars in this ultracompact system.  相似文献   

Development and Extension of Seawater Desalination by Reverse Osmosis   总被引：2，自引：0，他引：2  

高从堦 《中国海洋湖沼学报》2003,21(1):40-45

Seawater desalination has been people‘s fond dream since ancient times,the dream is now becoming a reality.This paper presents a brief development history of reverse osmosis.Much attention was paid to innovative development in mebranes,modules.equipments and applied technology,including asymmetric and composite membranes,spiral-wound element and hollow fiber module,energy recovery equipments and different technological processes.The extension of reverse osmosis,such as desalination,pre-concentration,integrated processes and nanofiltration,is also briefly mentioned.  相似文献   

MS 1603.6+2600: an accretion disc corona source?     

P. G. Jonker  M. van der Klis  C. Kouveliotou  M. Méndez  W. H. G. Lewin  T. Belloni 《Monthly notices of the Royal Astronomical Society》2003,346(2):684-688

We have observed the eclipsing low-mass X-ray binary MS 1603.6+2600 with Chandra for 7 ks. The X-ray spectrum is well fit with a single absorbed power law with an index of ∼2. We find a clear sinusoidal modulation in the X-ray light curve with a period of  1.7 ± 0.2 h  , consistent with the period of 1.85 h found before. However, no (partial) eclipses were found. We argue that if the X-ray flare observed in earlier X-ray observations was a type I X-ray burst, then the source can only be an accretion disc corona source at a distance of ∼11–24 kpc (implying a height above the Galactic disc of ∼8–17 kpc). It has also been proposed in the literature that MS 1603.76+2600 is a dipper at ∼75 kpc. We argue that, in this dipper scenario, the observed optical properties of MS 1603.6+2600 are difficult to reconcile with the optical properties one would expect on the basis of comparisons with other high-inclination, low-mass X-ray binaries, unless the X-ray flare was not a type I X-ray burst. In that case, the source can be a nearby soft X-ray transient accreting at a quiescent rate, as was proposed by Hakala et al., or a high-inclination source at ∼15–20 kpc.  相似文献   

CO-Observations of post-starburst galaxies     

Marco Barden  Linda J. Tacconi  Matthew D. Lehnert  Dimitra Rigopoulou 《Astrophysics and Space Science》2001,277(1):95-95

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An Investigation of Saturation-Capillary Pressure Relations in Two- and Three-Fluid Systems for Several NAPLS in Different Porous Media   总被引：2，自引：0，他引：2  

Robert D. Busby  Robert J. Lenhard  Dennis E. Rolston 《Ground water》1995,33(4):570-578

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Characteristics of Light Transmission in Summer and Winter and Its Relation to Sediment Transport in the East China Sea     

白虹  胡敦欣  庞重光 《中国海洋湖沼学报》2003,21(4):329-334

INTRODUCTIONTheSubeiShoalandtheChangjiangRiverestuarineareainthewestoftheHuanghaiandEastChinaSeasisoneofthemarginalseasintheworld ,wheresuspendedmatterisextremelyhigh .Here ,notonlyistheretheTaiwanWarmCurrentoneoftheKuroshio’sbranchesintheEastChinaSea,butalsotheHuanghaiCoastalCurrent,andChangjiangDilutedWater.Sothestrongmixingbetweenthecoastalandoffshorewaterscomplicatessuspendedmatterdistributioninthisarea.HowthesuspendedmatterdischargedfromtheChangjiangRiverandtheabandonedHuan…  相似文献   

FUZZY COMPREHENSIVE EVALUATION OF CONTAINER TRANSPORTATION MODES ALONG THE CHANGJIANG RIVER MAIN LINE AND ITS DELTA AREA   总被引：1，自引：0，他引：1  

ZHANGShi-yu XIAOHan-liang 《中国地理科学(英文版)》2003,13(3):259-261

The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in Chi-na. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifi-cally in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.  相似文献