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1.
In this paper, the responses of the interaction system of R.C. gravity single-leg platform to seismic excitation are mainly analysed. A set of nonlinear equations for the interaction system are established by using the wave, one is the soil-structure interaction and the other is the fluid-structure interaction. The seismic response of the interaction system is analysed for the influence of the asymmetric structure, fluid action, etc. with the input of seismic SH waves in any direction. The numerical results are given for a simple example.  相似文献   

2.
The purpose of every offshore oil and gas pipeline is to transport fluid through a conduit from one point to another, but differences in field location, water depth, development strategy, time of sanction, seafloor topography, ownership and other factors means that installed mileage is expected to have complex site, time and location dependencies. The purpose of this review is to describe and illustrate the main factors that impact pipeline construction in the deepwater U.S. Gulf of Mexico. Understanding the nature of these dependencies and the manner in which factors interact and impact pipeline construction is the principal goal of this review. System attributes and their impact on activity drivers are described using a series of mini case studies. Lessons learned are synthesized and summarized.  相似文献   

3.
General nutrient components including moisture, ash, crude protein, lipid and carbohydrate, inorganic elements, photosynthetic pigments, amino acids and fatty acids of Bangia sp. were analyzed and compared with Porphyra yezoensis. The results indicated that the content of protein, total amino acids and free amino acids accounted for 47.2% , 42.6% and 3.3% in dried Bangia sp. , respectively, all essential amino acids were present in relatively high levels and desirable composition. Lipid was 1.8%, in which the eicosapentaenoic acid (EPA) reached 50.5% . In per 100 g dried material, the content of chlorophyll, carotenoids, phycoerythrin and phycocyanin accounted for 766, 208, 4 600 and 2963 mg, respectively. Inorganic elements necessary for human body were found to be abundant in Bangia sp. The results showed that the nutritive value of Bangia sp. was the highest among algae reported so far, and the industry of Bangia sp. was provided with significant economic importance and developing potential.  相似文献   

4.
ThisworkisfundedbyagrantfromtheNationalKeyTaskProjectsof8thand9thFive-yearplanprogram.INTRODUCTIONInthepastyears,studiesonthevirusesofpenaeidshrimpshavemadegreatprogressinvari-ouscountries.Rightnow,aboutl4virusesofpenaeidshrimpswerefound,i.e.BP(Baculoviruspenaei,Couch,1974),MBV(Penaeusmonndonbaculovirus,Lightneretal.,1983)orPBV(Penaeusplebejusbaculovirus,Lesteretal.,1987),BMN(Baculovirusmidgutglandnecrosisvirus,Sanaetal.,1981),PHRV(Penaeushybridrod-shapedvirus,Owensetal.,199l),…  相似文献   

5.
This pilot study attempts to demonstrate some underlying scanning electron microscopy themes of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected from various littoral environments. An attempt was made to differentiate samples on surface textures alone, but limitations of using this technique in sedimentological isolation were apparent. Statistical analysis of checklist data and photographic evidence revealed some of the more important feature combinations used in environmental diagnosis. The use of discriminant analysis provided quantitative sample separation.  相似文献   

6.
7.
Materials Wild algae was collected by divers from the Sanggou Bay, Rongcheng County. The mature fe-male gametophyte and tetrasporaphyte were selected as mother seaweed, washed with purified seawaterand prepared for spore collection.  相似文献   

8.
DivisionofhydroclimaticareaoverChinaseas—Ⅱ.ClusteranalysisandfuzzyISODATA.¥ChenShangjiandYaoShiyu(ReceivedAugust1,1993;accept...  相似文献   

9.
A histological and ultrastructural study was performed on the development of the head kidney, thymus, and spleen in Pseudosciaena crocea aging in range from just hatching to the 60th day after hatching (DAH). Head kidney was first present on the 3rd DAH. Primordial haemopoietic stem cells were first observed in the head kidney which rapidly differentiate into different cellular types. Progenitor spleen was present on the 4th DAH, located close to the gut, which soon became rich in blood capillaries, red blood cells and thrombocytes. The thymus was obvious on the 4th DAH, and was located on either side of the upper corner of the opercular cavity, closely under the membrance of the opercuhr cavity. The thymus was the last lymphoid organ to appear but showed a quick development. This organ seemed to originate from haemopoietic stem cells migrating from the head region of the kidney. The thymus consisted of outer thymocytic and inner epithelioid zones. There was no obvious demarcation between them, but both zones were visible. Small lymphocytes appeared, or lymphoid organs become lymphoid, in the sequence thymus, head kidney and spleen. Only a small number of lymphocytes appeared in the later stages. Non-specific systems may play an important role in the immunocompetence mechanisms of P. crocea during its early development stage.  相似文献   

10.
Haliphthoros philippinensis, a marine mastigomycete isolated from larvae of the jumbo tiger prawn Penaeus monodon, is described and illustrated as new. The fungus grew at a temperature range of 13.5 to 36.3℃, with the optimum of 29.3-34.5℃. Its growth occurred in peptone-yeast extract-glucose ( PYG ) broth containing 0.3-7% NaCl, with the optimum concentrations of 1 to 4%. At 8% or more NaCl concentrations, the growth was not observed. Its pH range for growth was 5 to 11.  相似文献   

11.
QinYunshan,SeniorScientist,InstituteofOceanology,AcademiaSinica.Male,borninShandongProvinceonJulle1,1933.GraduatedfromBeijingCollegeofGeologyin1956.DirectoroftheInstituteofOceanology,AcademiaSinica;DirectoroftheChineseSocietyofOceanologyandLimnology,Editorof"GeologyofBohaiSea"(SciencePress,1985)and"GeologyofEastChinaSea"(SciencePress,1988).HepublishedinvariousChineseandwor1djournalsmoretban50papers,suchas"PrimarystudyonthereliefandsedimenttypeofthecontinentalshelfofChina"(Ocean…  相似文献   

12.
13.
Lagenidium scyllae a marine mastigomycete from ova and larvae of the mangrove crab, is described and illustrated as new. The fungus grew at a temperature range of 16 to 42℃, with the optimum of 22.5-31.8℃. It grew well in peptone-veast-glucose ( PYG ) broth containing 2-3% NaCl, although did through a range of NaCl contents between O and 7%.At 8% NaCl or above the growth failed to occur in the medium.In PYG-sea water medium, it grew at a pH range of 5 to 11.  相似文献   

14.
Within the framework of the integral model in isopycnic coordinates including the upper mixed layer, we study the rearrangement of temperature and salinity fields in the Dead Sea. It is forced by the variability of atmospheric factors and mass fluxes through the lateral boundaries of the basin, which are connected with the freshwater run-off to the sea and the outflow from the sea to the shallow south bay, where evaporator installations for salt extraction are located. Such factors as solar radiation, wind velocity, air temperature, and relative humidity are prescribed. Evaporation is calculated with the use of a bulk formula, whereas precipitation intensity and discharge through the lateral boundaries are determined as functions of the sea level obtained from observations. This model reflects the specific character of the Dead Sea and takes into account the effect of water salinity on its evaporation, salt concretion, and mechanical evaporation. Comparison with the data of observations shows that the proposed model fairly precisely describes the observed specific features of the thermohaline water structure in the meromictic (1992–1996) and holomictic (1996–2000) periods.  相似文献   

15.
This paper comments and discusses the article ‘Evaluating the influence of candidate terrestrial protected areas on coral reef condition in Fiji׳ by Klein et al. in Marine Policy 44 2014. Klein et al. integrate land-sea planning by optimising the design of Fiji׳s expanded protected area network to benefit coral reefs, while maintaining a terrestrial network that is representative of Fiji׳s various terrestrial ecosystems. They discuss the benefits of various spatial conservation models compared to a candidate protected area network proposed by Fiji׳s Protected Area Committee (FPAC), which is based on expert knowledge and a scoring system. This paper argues that their analyses are best interpreted as the FPAC network outperforming the models proposed by Klein et al. in protecting terrestrial biodiversity. The FPAC network performs better because it includes data that was not available for spatial modelling, especially the percentage of endemic species per ecosystem and the practicalities of protecting an area earmarked for conservation. This suggests that expert knowledge can be an important resource for conservation planning, especially in developing countries, and that spatial conservation planning should harness this knowledge.  相似文献   

16.
Lagenidium scyllae a marine mastigomycete from ova and larvae of the mangrove crab, is described and illustrated as new. The fungus grew at a temperature range of 16 to 42℃, with the optimum of 22.5—31.8℃. It grew well in peptone-veast-glucose(PYG) broth containing 2—3%NaCl.  相似文献   

17.
Recruitment of glass‐eels into freshwater is in two distinct phases characterised by behavioural differences: an initial invasion from the sea, and an upstream migration. Catches made at night in the Makara Stream, Wellington (41° 13'S, 174° 43’ E) indicate that the invasion by both New Zealand species commences in July, with that of the long‐finned eel Anguilla dieffenbachii Gray finishing by November, and that of the short‐finned eel A. ausiralis schmidlii Phillipps by December.

The length of post‐metamorphic sea‐life influences both morphology and behaviour of the glass‐eels. Differences in this period of sea‐life between early and late season glass‐eels explain the initial avoidance but later attraction of fresh water to the glass‐eels. Responses to fresh water also explain the preference for early season glass‐eels to invade on the flood tide and late season glass‐eels on the ebb tide. Neither the lunar cycle nor rainfall appear to be significant influences on invasion periodicity.  相似文献   

18.
I~IOXWith regard tO the 5,tudy on the planktonic copeal distributions in the Kuroshio waters ofthe East China Sea and its adjacent areas, a great ~nt of reSearch work has been made by somescholars at home (He and Yang, 1990; Meng et al., 1990; He, 1990; Liu et al., 1991; He etal., 1992; He et al., 1994). HOwever, the most of them were made in a single season, and it isabet about in the research of the various aspects of species comPOSition, abundance distributionand ecological characte…  相似文献   

19.
The fractal characteristics of the canopy structure o! B. gymnorrhiza population are investigated by fractal dimension analysis in the National Shankou Mangrove Nature Reserve. The 3-year-old branches have box dimensions between 1.22 and 1.55, showing thecomplexity degree of branching structure and the ability of occupying and utilizing ecological space. It may be considered that fractal dimension provides a useful index for the study of light utilization efficiencies and growth processes of B. gymnorrhiza. Calculated by using the two-surface method, the fractal dimensions for the crown pattern of individuals with ages of 20 to 50 years range from 2.21 to 2.54, indicating that the filling degree of foliage to a tree crown is relatively low and B. gymnorrhiza has the property of a sun plant.Along with the increase of ages of individuals, the filling degree of foliage to a tree crown changes from high to low, and so does the fractal dimeilsion. The box dimensions obtained from the grayscale curves of population canopy are between 1.47 and 1.61. The greater the box dimension, the more loosely organized the canopy spatial structure, and the more the light spots. The canopy structural information and complexity of a population can be effectively captured by box dimensions obtained from canopy grayscale curves.  相似文献   

20.
I~IOWThe area north of Taiwan is a mixing waters with complicate hydrographic features because itis influenced by the pushing and mixing of different water masses such as the Zhejiang -- Fujiancoastal water, the Taiwan Strait water, the Kuroshio surface water, the KurOShio sub-surfacewater and so on. The planktonic copepods in the area are also very complex and various. From research on species compoSition and ~nal variation, diversity and characteristics of copeal community in the area, …  相似文献   

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