1996 Vol. 15, No. 3
Display Method:
1996, (3): 283-296.
Abstract:
This study presents a boundary-fitted grid(BFG) numerical model with an aim to simulate the tidal currents and diffusion of pollutants in complicated nearshore areas.To suit the general model to any curvilinear grids,generalized 2-D shallow sea dynamic equations and the advection diffusion equation are derived in curvilinear coordinates,and the contravariant components of the velocity vector are adopted for easily realizing boundary conditions and making the equations conservational.As the generalized equations are not limited by a specific coordinate transformation,a self-adaptive grid generation method is then proposed conveniently to generate a boundary-fitted and varying spacing grid.The calculation in the Yangpu Bey and the Xinying Bey shows that this is an effective model for calculating tidal currents end diffusion of pollutants in the more complicated nearshore areas.
This study presents a boundary-fitted grid(BFG) numerical model with an aim to simulate the tidal currents and diffusion of pollutants in complicated nearshore areas.To suit the general model to any curvilinear grids,generalized 2-D shallow sea dynamic equations and the advection diffusion equation are derived in curvilinear coordinates,and the contravariant components of the velocity vector are adopted for easily realizing boundary conditions and making the equations conservational.As the generalized equations are not limited by a specific coordinate transformation,a self-adaptive grid generation method is then proposed conveniently to generate a boundary-fitted and varying spacing grid.The calculation in the Yangpu Bey and the Xinying Bey shows that this is an effective model for calculating tidal currents end diffusion of pollutants in the more complicated nearshore areas.
1996, (3): 297-305.
Abstract:
Based on the definition and concept introduced in this paper,the theoretical expression of surface slope bispectrum for two-dimensional random waves is derived.Furthermore,the skewness of surface elevation distribution and that of surface she distribution are respectively employed to define the up-down and front-back asymmetry of a waves hape so that the relations between bispectrum and skewness are proposed.Through these relations,the updown end front-back asymmetry of the wave shape can be quantitatively determined by means of the bispectral analyses of observed wave data.
Based on the definition and concept introduced in this paper,the theoretical expression of surface slope bispectrum for two-dimensional random waves is derived.Furthermore,the skewness of surface elevation distribution and that of surface she distribution are respectively employed to define the up-down and front-back asymmetry of a waves hape so that the relations between bispectrum and skewness are proposed.Through these relations,the updown end front-back asymmetry of the wave shape can be quantitatively determined by means of the bispectral analyses of observed wave data.
1996, (3): 307-321.
Abstract:
In this paper.Some short time series of observed data an section 18°20'N in the tropical western Pacific were reorganized to give mixed depth-time series,and processed by means of empirical orthogonal function analysis.It is indicated that the original form of element distribution could be obtained by linear combination of several main canonical distribution functions,and the intrinsic structure of element distribution on a certain section and its variation properties could be revealed by canonical distribution functions and profiles in corresponding periods.
In this paper.Some short time series of observed data an section 18°20'N in the tropical western Pacific were reorganized to give mixed depth-time series,and processed by means of empirical orthogonal function analysis.It is indicated that the original form of element distribution could be obtained by linear combination of several main canonical distribution functions,and the intrinsic structure of element distribution on a certain section and its variation properties could be revealed by canonical distribution functions and profiles in corresponding periods.
1996, (3): 323-330.
Abstract:
An analytical method of predicting the annual variation rate(AVR) of global sea-level(GSL) is developed.Through the calculation by using the mean sea-level data collected from the tidal gauge stations over the world.a GSL rise of 0.15-0.16 cm/a is obtained.The predicted values of AVR of GSL for the 21st century are presented.The authors' results have been compared to Shaw reported by other scientists at home and abroad.The method proposed here is more convenient and precise.
An analytical method of predicting the annual variation rate(AVR) of global sea-level(GSL) is developed.Through the calculation by using the mean sea-level data collected from the tidal gauge stations over the world.a GSL rise of 0.15-0.16 cm/a is obtained.The predicted values of AVR of GSL for the 21st century are presented.The authors' results have been compared to Shaw reported by other scientists at home and abroad.The method proposed here is more convenient and precise.
1996, (3): 331-344.
Abstract:
Besed on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information,the concept model and concept system of coral islets and reef are proposed.Then twin-tree remote sensing information model(or different kinds of reef is constructed by using abstracted islets and reef's primifive,and the structure recognition system for coral islets and reef type is developed.
Besed on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information,the concept model and concept system of coral islets and reef are proposed.Then twin-tree remote sensing information model(or different kinds of reef is constructed by using abstracted islets and reef's primifive,and the structure recognition system for coral islets and reef type is developed.
1996, (3): 345-354.
Abstract:
Synthetic 1nm manganate has been made in the laboratory at low temperature.The d-spacing of which shows 1.002 nm,0.501 nm and 0.34 nm respectively.As the analogue of natural 1nm manganate,it has been used for a series of experiments of divalent canons substitution.The results indicate that the 1nm manganate has very strong canon substitution capacity,which probable is the reason of the valuable metal such as Cu,Ni and Co enriched in the manganese nodules.The preference of canons substituting into S 1nm manganate is Cu > Co > Zn ≥ Ni > Ca > Mg.In the manganese nodules,the content of Ni is usually higher than that of Cu and Co,but in the cation substitution,the latter two are more preference than the former.Cane can infer from this differentiation that the post-deposition canon substitution is not the sole mechanism by which the valuable metals enter the manganese nodules.It could be the resups of combined effects of both original formation and the post-deposition substitution of canons,which leads to the enrichment of valuable metal in the manganese nodules.
Synthetic 1nm manganate has been made in the laboratory at low temperature.The d-spacing of which shows 1.002 nm,0.501 nm and 0.34 nm respectively.As the analogue of natural 1nm manganate,it has been used for a series of experiments of divalent canons substitution.The results indicate that the 1nm manganate has very strong canon substitution capacity,which probable is the reason of the valuable metal such as Cu,Ni and Co enriched in the manganese nodules.The preference of canons substituting into S 1nm manganate is Cu > Co > Zn ≥ Ni > Ca > Mg.In the manganese nodules,the content of Ni is usually higher than that of Cu and Co,but in the cation substitution,the latter two are more preference than the former.Cane can infer from this differentiation that the post-deposition canon substitution is not the sole mechanism by which the valuable metals enter the manganese nodules.It could be the resups of combined effects of both original formation and the post-deposition substitution of canons,which leads to the enrichment of valuable metal in the manganese nodules.
1996, (3): 355-363.
Abstract:
The experimental results of the redox of manganese and ferro ions by manganese bacteria are described.Under the aerobic conditions,the manganese bacteria can oxidate Mn2+ into Mn4+.In the course of the manganese bacteria multiplication,the continual increase of environmental pH is advantagcous to the oxidation of manganese and the rise of environmental temperature helps the bacteria to speed the oxidation of manganese ions.The manganese bacteria can lastly oxidate Fe2+ in the culture containing low valent Ferro into Fe3+.its oxidation speed being faster than that of manganese oxide.Under the anaerobic conditions,the manganese bacteria can reduce high valent Ferro in solution into low valent ferro and distinctly lower the environmental pH.
The experimental results of the redox of manganese and ferro ions by manganese bacteria are described.Under the aerobic conditions,the manganese bacteria can oxidate Mn2+ into Mn4+.In the course of the manganese bacteria multiplication,the continual increase of environmental pH is advantagcous to the oxidation of manganese and the rise of environmental temperature helps the bacteria to speed the oxidation of manganese ions.The manganese bacteria can lastly oxidate Fe2+ in the culture containing low valent Ferro into Fe3+.its oxidation speed being faster than that of manganese oxide.Under the anaerobic conditions,the manganese bacteria can reduce high valent Ferro in solution into low valent ferro and distinctly lower the environmental pH.
1996, (3): 365-376.
Abstract:
This paper makes an analysis and study of the plankton samples collected from the Kuroshio and its adjacent area in the north of the East China Sea during the seven successive years(from 1986 to 1992) in the implementation of the programme "China-Japan Joint Research on the Kuroshio" as well as a brief summary of the distribution of the biotnass of food zooplankton and its relation to the oceanic environment.The results indicate that the biomass of zooplankton in the study area is relatively low,with en annual mean of 71.22 mg/m3 only.The seasonal variation of biomass is not obvious and salinity is an important factor influencing seasonal and annual variations of zooplankton biomass in the study area.The Kuroshio front in the East China Sea and the Tsushima Warm Current front divide the study area into two parts from north to south in the vicinity of the 200 m isobath:the biotrtass in the western part was greater than 50 mg/m3,whereas was less than 50 mg/m3 in the eastern part.The spetiotemporal distributions of different ecological groups of zooplankton and their biotrutss basically reflect the basic features of the hydrological conditions in each season in the study area.
This paper makes an analysis and study of the plankton samples collected from the Kuroshio and its adjacent area in the north of the East China Sea during the seven successive years(from 1986 to 1992) in the implementation of the programme "China-Japan Joint Research on the Kuroshio" as well as a brief summary of the distribution of the biotnass of food zooplankton and its relation to the oceanic environment.The results indicate that the biomass of zooplankton in the study area is relatively low,with en annual mean of 71.22 mg/m3 only.The seasonal variation of biomass is not obvious and salinity is an important factor influencing seasonal and annual variations of zooplankton biomass in the study area.The Kuroshio front in the East China Sea and the Tsushima Warm Current front divide the study area into two parts from north to south in the vicinity of the 200 m isobath:the biotrtass in the western part was greater than 50 mg/m3,whereas was less than 50 mg/m3 in the eastern part.The spetiotemporal distributions of different ecological groups of zooplankton and their biotrutss basically reflect the basic features of the hydrological conditions in each season in the study area.
1996, (3): 377-395.
Abstract:
In this paper,the irregular wave-induced seepage action on cylinders resting on rubble mound foundatoin(RMF) is studied by means of finite element method(FEM).The hydraulic resistance inside RMF is assumed to satisfy the nonlinear Forchheimer's equation and the seepage in the seabed is also considered.Model tests show good agreement with the numerical results.The influence of several main parameters is discussed on the basis of vast calculations.In addition,the ratio of seepage forces,induced by regular and irregular waves respectively,is analyzed and thus a computational method is put forward for protical engineering application to simplify the calculation of irregular wave-induced seepage forces.
In this paper,the irregular wave-induced seepage action on cylinders resting on rubble mound foundatoin(RMF) is studied by means of finite element method(FEM).The hydraulic resistance inside RMF is assumed to satisfy the nonlinear Forchheimer's equation and the seepage in the seabed is also considered.Model tests show good agreement with the numerical results.The influence of several main parameters is discussed on the basis of vast calculations.In addition,the ratio of seepage forces,induced by regular and irregular waves respectively,is analyzed and thus a computational method is put forward for protical engineering application to simplify the calculation of irregular wave-induced seepage forces.
1996, (3): 397-408.
Abstract:
1996, (3): 409-421.
Abstract:
