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901.
Lü Songhui Chao Aimin Liang Qianyan Cen Jingyi Wang Jianyan Jiang Tao Li Si 《中国海洋湖沼学报》2022,40(6):2146-2163
Journal of Oceanology and Limnology - The naked dinoflagellate Takayama acrotrocha was identified as responsible for a bloom in Shenzhen Bay, Guangdong, China, in early spring 2021. The... 相似文献
902.
903.
904.
Roberto Soria Kinwah Wu Duncan K. Galloway 《Monthly notices of the Royal Astronomical Society》1999,309(2):528-532
We carried out I , R , V and B photometric observations of the neutron star X-ray binary RXTE J2123−058 shortly after the end of the X-ray outburst in mid-1998. We adopt the low-mass binary model to interpret our observations. After folding our data on the 0.24 821‐d orbital period, and correcting for the steady brightness decline following the outburst, we observed sinusoidal oscillations with hints of ellipsoidal modulations which became progressively more evident. Our data also show that the decline in brightness was faster in the V band than in the R and I bands. This suggests both the cooling of an irradiation-heated secondary star and the fading of an accretion disc over the nights of our observations. 相似文献
905.
We analyse data obtained by different ground-based video camera systems during the 1999 Leonid meteor storm. We observe similar
activity profiles at nearby observing sites, but significant differences over distances in the order of 4,000 km. The main
peak occured at 02:03 UT (λ⊙=235.286, J2000, corrected for the time of the topocentric stream encounter). At the Iberian peninsula quasi-periodic activity
fluctuations with a period of about 7 min were recorded. The camera in Jordan detected a broad plateau of activity at 01:39–01:53
UT, but no periodic variations. The Leonid brightness distribution derived from all cameras shows a lack of faint meteors
with a turning point close to +3m, which corresponds to meteoroids of approximately 10-3 g. We find a pin-point radiant at αalpha=153.65 ±0.1, δ=21.80 ±0. (λ⊙=235.290). The radiant positionis identical before and after the storm, and also during the storm no driftis observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
906.
907.
A semi-numeric method was used to study the evolution of a general-relativistic radiating shell in its Post-Newtonian and
Newtonian approximations. The solutions, where the main parameters are given reasonable values, show that a relativistic effect
can be found in X-ray-burster-like objects.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
908.
909.
Hübscher C. Breitzke M. Michels K. Kudrass H. R. Spiess V. Wiedicke M. 《Marine Geophysical Researches》1998,20(1):57-71
An ultra-high-resolution seismic study of the eastern Bengal Shelf with the parametric narrow-beam echosounder Parasound allows the interpretation of late Quaternary depositional patterns in terms of seismic stratigraphy. Accommodation space was still present on the outer shelf during the last lowstand, where a prograding delta developed in the western survey area. Oolitic beach ridges were later formed on top of this lowstand delta. Farther east, large parts of the shelf were exposed to subaerial erosion and a river system extended seaward across the area. A subaqueous highstand delta prograded southwards following the maximum transgression about 7,000 years ago. Its foreset beds exhibit acoustic voids very likely generated by sediment liquefaction, possibly caused by episodic energetic events such as major cyclones and/or earthquakes. Bottomset sediments extend seaward close to the shelf break in the west, whereas no Holocene sediments cover the outer shelf in the east. 相似文献
910.
Impact of Climate Change on Hydrological Regimes and Water Resources Management in the Rhine Basin 总被引:18,自引:2,他引:18
H. Middelkoop K. Daamen D. Gellens W. Grabs J. C. J. Kwadijk H. Lang B. W. A. H. Parmet B. Schädler J. Schulla K. Wilke 《Climatic change》2001,49(1-2):105-128
The International Commission for the Hydrology of the Rhine basin (CHR) hascarried out a researchproject to assess the impact of climate change on the river flow conditionsin the Rhine basin. Along abottom-up line, different detailed hydrological models with hourly and dailytime steps have beendeveloped for representative sub-catchments of the Rhine basin. Along atop-down line, a water balancemodel for the entire Rhine basin has been developed, which calculates monthlydischarges and which wastested on the scale of the major tributaries of the Rhine. Using this set ofmodels, the effects of climatechange on the discharge regime in different parts of the Rhine basin werecalculated using the results ofUKHI and XCCC GCM-experiments. All models indicate the same trends in thechanges: higher winterdischarge as a result of intensified snow-melt and increased winterprecipitation, and lower summerdischarge due to the reduced winter snow storage and an increase ofevapotranspiration. When the resultsare considered in more detail, however, several differences show up. These canfirstly be attributed todifferent physical characteristics of the studied areas, but different spatialand temporal scales used in themodelling and different representations of several hydrological processes(e.g., evapotranspiration,snow melt) are responsible for the differences found as well. Climate changecan affect various socio-economicsectors. Higher temperatures may threaten winter tourism in the lower wintersport areas. The hydrologicalchanges will increase flood risk during winter, whilst low flows during summerwill adversely affectinland navigation, and reduce water availability for agriculture and industry.Balancing the required actionsagainst economic cost and the existing uncertainties in the climate changescenarios, a policy of `no-regretand flexibility' in water management planning and design is recommended, whereanticipatory adaptivemeasures in response to climate change impacts are undertaken in combinationwith ongoing activities. 相似文献