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1.
Computational Techniques of 2D Tidal Flow in Estuaries and Bays   总被引:1,自引:0,他引:1  
- Some problems in the numerical calculation of tidal flow in estuaries and bays, such as distribution bed roughness, relationship between model moving boundary and water volume balance, remedy of certain shortage under open boundary conditions, smooth transfer of the controlling message for the inner boundaries of nested model, can not be solved usually by means of the fundamental equations and computing mode adopted in the numerical model, but can be done by the measures which not only satisfy the physical features but also are convenient for operation. Based on the calculated samples of some areas of Modaomen, Lingdingyang and Huangmaohai of the Pearl River Estuary, and Shuidong Bay (a typical barrier- lagoon tidal channel) in Guangdong Province, method and process of calculation for the above mentioned problems are briefly presented in this paper.  相似文献   

2.
The effects of ambient CO2/ambient UV-B, enriched CO2/ambient UV-B, ambient CO2/enhanced UV-B, and enriched CO2/enhanced UV-B on the ultrastructure of Dunaliella salina were investigated. (1) The ultrastructure of D..salina cell in the control experiment showed that the arrangement of thylakoid lamellae was regular, and there were many large starch grains among the thylakoid lamellae. A prominent well-developed pyrenoid was found in the middle of the chloroplast. Nucleus envelope and nucleolus were clearly observed. The Golgi apparatus accompanied by numerous vesicles with a compact arrangement of cisternae and the peripheral tips of the cisternae were swollen to a size comparable to that of some of the associated vesicles. (2) The ultrastructure of D. salina cell in enriched CO2 showed that the arrangement of thylakoid was regular and the lamellae were vivid. Developed pyrenoids were found in the low-CO2-grown cells, but not in the high-CO2-grown cells. The mitochondria cristae were vivid. The arrangement of Golgi apparatus was compact. (3) The ultrastructure of D. salina cell in enhanced UV-B showed that the thylakoid was dissolved and the cells had a less developed pyrenoid or no detectable pyrenoid. Part of the nucleus envelope was dissolved. The number ofmitochondria was increased and some mitochondria cristae were disintegrated. The starch grains were broken apart into many small starch grains. The Golgi apparatus with a loose arrangement ofcistemae and the peripheral tips of the Golgi cistemae were not especially swollen, with several large associated vesicles. (4) The ultrastructure of D. salina cell in the enriched CO2/enhanced UV-B showed that part of the thylakoid and nucleus envelopes of some cells were dissolved. The pyrenoid was larger than that of the enhanced UV-B. There were many mitochondria between stroma and chloroplast membrane, but mitochondria cristae were partly dissolved. Many small starch grains were accumulated in cells. The starch sheath was broken into several discontinuous starch grains with different sizes. The arrangement of Golgi apparatus was loose. Above all, although the enriched CO2 can alleviate the damage induced by the UV-B radiation, the effects of experimental UV-B radiation were larger than the effects of actual UV-B radiation, the damage induced by the UV-B radiation was so severe, therefore, CO2 enrichment could not restore the ultrastructure to the control level.  相似文献   

3.
A pair of buoys (system), MET and OPTICAL, consisting of fully automated hyperspectral radiometers, fluorometer, and meteorological sensors, has been realized and deployed in deep ocean case-I site at Kavaratti in Lakshadweep, Arabian Sea, for preprogrammed in situ data collection and transmission via INSAT-3C satellite. The buoy of described configuration is capable of measuring in-water optical and biological parameters in an unattended manner for long-term time series with less vertical tilt. A robotic sun/sky photometer installed on Kavaratti Island simultaneously provides information on aerosols over the site. A combination of these parameters available hourly in real time throughout the day from unattended systems in the ocean as well as on island provides an ideal reference site. The paper reports recent collection of bio-optical marine observations over the site and use of the data for OCM-2 vicarious calibration and validation of geophysical products.  相似文献   

4.
1 Introduction The amount of stratospheric ozone was being re duced due to anthropogenic emission of chlorofluoro carbons (CFCs) and nitrogen orides (Molina and Row land, 1974; Rowland, 1989; Yang et al., 1998; Xiao e al., 2005). This reduction of ozone r…  相似文献   

5.
Two multispectral threshold techniques have been developed and tested for the automatic classification of AVHRR/NOAA and SEVIRI/Meteosat-10 data. They provide day-and-night detection and the assessment of cloud-cover parameters, as well as the discrimination of precipitation zones and severe weather phenomena. The validation of output information products, which has been performed with ground-based conventional meteorological observations and radar data, as well as with independent satellite-based estimates of cloud cover and precipitation parameters, confirms the feasibility of developed techniques and reasonable accuracy of output products. Therefore, the technique is concurrent to those implemented in current foreign satellite centers.  相似文献   

6.
Spectrum and self-excite characters are the two significant characters of the dynamics of sea ice. The spectrum character of sea ice is mainly shown by the spectrum of ice force. The spectrum character of the sea ice is its intrinsic attributes. When the spectrum of ice force from the dynamic response of ice and structure interaction are evaluated, the effect of dynamic character of the structure must be eliminated. In this paper, the ice force spectrum at Bohai Bay and Liaodong Bay is evaluated from the displacement and strain responses of a single degree and a multi-degree freedom structure. The evaluated ice force spectrum can be used to define the spectrum character of ice in the analysis of ice induced vibration.  相似文献   

7.
Distribution of dominant species and abundance of nannofossils in surface sediments of the central and northern partsof the S...  相似文献   

8.
Observations and Estimations of Directional Spectrum of Sea Waves   总被引:1,自引:1,他引:1  
The directional spectrum is one of the basic characteristics of sea waves. The observations of directional spectrum of sea waves were successfully conducted at platform Bohai 8 during 1991 and 1992 using a wave gage array for the first time in China. Based on the field data, the directional spectrum which depends on the wave growth is given in this paper. Before observations, the effects of the type of gage array, the distance between the gages and the platform itself on the measured results and the precision of some methods for estimating the directional spectrum were investigated and compared with the methods of numerical simulations and model tests of multi-direcitonal irregular waves. This ensures the quality of the observations and estimations of the directional spectrum.  相似文献   

9.
Bispectrumandasymmetryofwaveshape¥DingPingxing;KongYazhen;andSunFu(StateKeyLaboratoryOfEstuarineand ̄alR ̄h,InstituteofEStuarin...  相似文献   

10.
The data were collected during Chinese Arctic and Antarctic Expeditions in the western Arctic Ocean and the marginal sea ice zone (MSIZ) of the Southern Ocean, respectively in the boreal summer from July to September of 1999 and in the austral summer from December of 1999 to January of 2000. The concentrations of CO2 in surface water of the survey regions would mostly present lower than those in the atmosphere. A significant biological driving force could also been observed in summer waters in both of the above oceans. Air to sea CO2 fluxes were also calculated to compare oceanic uptake capacity of CO2 in both oceans with the world oceans using Liss, Wanninkhof, and Jacobs‘s methods. The averaged CO2 fluxes of air to sea in the western Arctic Ocean or in the MSIZ of the Southern Ocean doubled that in the world oceans.  相似文献   

11.
《海洋学报(英文版)》1996,15(4):539-556
AstudyofanchoringgeographiccoordinatesandcalculatingzenithandazimuthofsunandscannerforoceanicsatellitedataINTRODUCTIONThescan...  相似文献   

12.
This paper deals mainly with etiology, pathology, sympotomatology, harmfulness, preventive measures and treatment of larval mycosis (caused by Lagenidium sp. ) and of ciliate disease (caused by Zoothamnium sp. ) of penaeid shrimp larvae.  相似文献   

13.
To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China‘ s coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management.  相似文献   

14.
15.
The coastal zone and offshore are clearly of major economic and social importance,in thesame time it causes a series of problems of resources and ecosystem too.The research on and development of integrated application techniques for remote sensing provide not only a microcosmic and dynamic and synchronous technical means to the monitor,but also an integrated technical scheme to harmonically solve the ecological environment problem.The system is designed to focus on the application techniques of multi-sources remote sensing data.By developing remote sensing information extraction module,integrated user platform,and application module objected to the real ocean procedure for China''s coastal zone and offshore,the information system consists of the management of prodigious amount of data,display,analysis,simulation and output will be constructed and implemented.The final objective is to transform the research on ocean remote sensing into application.  相似文献   

16.
In crude enzymes extracted from the Lunella cornata coreensis there are two algi- nases with different functions. One of the alginases can cleave the middle bond of the algin molecular chains in the reactive condition of 30 μM pH 7.5 Tris-HCl buffer and 50 μM KCl per ml of reactive mixture Ⅰ. This enzyme can readily decrease the viscosity, but the reducing groups increase slowly in the algin reactive mixture Ⅰ. Thus, it is defined as alginase Ⅰ.  相似文献   

17.
A 3D coupled biogeochemical–hydrodynamic model (MIRO-CO2&CO) is implemented in the English Channel (ECH) and the Southern Bight of the North Sea (SBNS) to estimate the present-day spatio-temporal distribution of air–sea CO2 fluxes, surface water partial pressure of CO2 (pCO2) and other components of the carbonate system (pH, saturation state of calcite (Ωca) and of aragonite (Ωar)), and the main drivers of their variability. Over the 1994–2004 period, air–sea CO2 fluxes show significant inter-annual variability, with oscillations between net annual CO2 sinks and sources. The inter-annual variability of air–sea CO2 fluxes simulated in the SBNS is controlled primarily by river loads and changes of biological activities (net autotrophy in spring and early summer, and net heterotrophy in winter and autumn), while in areas less influenced by river inputs such as the ECH, the inter-annual variations of air–sea CO2 fluxes are mainly due to changes in sea surface temperature and in near-surface wind strength and direction. In the ECH, the decrease of pH, of Ωca and of Ωar follows the one expected from the increase of atmospheric CO2 (ocean acidification), but the decrease of these quantities in the SBNS during the considered time period is faster than the one expected from ocean acidification alone. This seems to be related to a general pattern of decreasing nutrient river loads and net ecosystem production (NEP) in the SBNS. Annually, the combined effect of carbon and nutrient loads leads to an increase of the sink of CO2 in the ECH and the SBNS, but the impact of the river loads varies spatially and is stronger in river plumes and nearshore waters than in offshore waters. The impact of organic and inorganic carbon (C) inputs is mainly confined to the coast and generates a source of CO2 to the atmosphere and low pH, of Ωca and of Ωar values in estuarine plumes, while the impact of nutrient loads, highest than the effect of C inputs in coastal nearshore waters, also propagates offshore and, by stimulating primary production, drives a sink of atmospheric CO2 and higher values of pH, of Ωca and of Ωar.  相似文献   

18.
Iron–manganese formations and igneous rocks of submarine elevations in the Sea of Japan contain overlapping mineral phases (grains) with quite identical morphology, localization, and chemical composition. Most of the grains conform to oxides, intermetallic compounds, native elements, sulfides, and sulfates in terms of the set of nonferrous, noble, and certain other metals (Cu, Zn, Sn, Pb, Ni, Mo, Ag, Pd, and Pt). The main conclusion that postvolcanic hydrothermal fluids are the key sources of metals is based upon a comparison of the data of electron microprobe analysis of iron–manganese formations and igneous rocks dredged at the same submarine elevations in the Sea of Japan.  相似文献   

19.
The TiO2--Mn--TiO2 multilayers are successfully grown on glass and silicon substrates by alternately using radio frequency reactive magnetron sputtering and direct current magnetron sputtering. The structures and the magnetic behaviours of these films are characterised with x-ray diffraction, transmission electron microscope (TEM), vibrating sample magnetometer, and superconducting quantum interference device (SQUID). It is shown that the multi-film consists of a mixture of anatase and rutile TiO2 with an embedded Mn nano-film. It is found that there are two turning points from ferromagnetic phase to antiferromagnetic phase. One is at 42 K attributed to interface coupling between ferromagnetic Mn3O4 and antiferromagnetic Mn2O3, and the other is at 97 K owing to the interface coupling between ferromagnetic Mn and antiferromagnetic MnO. The samples are shown to have ferromagnetic behaviours at room temperature from hysteresis in the M--H loops, and their ferromagnetism is found to vary with the thickness of Mn nano-film. Moreover, the Mn nano-film has a critical thickness of about 18.5 nm, which makes the coercivity of the multi-film reach a maximum of about 3.965times 10 - 2 T.  相似文献   

20.
The study of the behavior of concrete under biaxial stresses is essential to the design of offshore concrete platforms. Using the multiaxial test apparatus developed by the authors, the deformation and strength of concrete under biaxial stresses are studied experimentally. Based on the test data, an endochronic damage constitutive model and a failure criterion are proposed. According to the above model, an incremental nonlinear iterative programme is developed, and a plate sample in plane stress state is analyzed.  相似文献   

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