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51.
用包埋脱水法冰冻保存海洋饵料金藻 总被引:4,自引:0,他引:4
用包埋脱水法冰冻保存绿色巴夫藻(Pavlova uiridis)、湛江等鞭金藻(Isochrysis zhanjiangensis)和球等鞭金藻(Isochrysis galbana 3011)等三种海洋饵料金藻,探讨了脱水速率、胶球含水量以及化冻后恢复方法对冰冻保存存活率的影响。结果表明,三种藻都在-0.9%含水量/h的平均脱水速率下获得最高存活率:各种藻在冰冻前的胶球最佳含水量不同,绿色巴夫藻为35%,湛江等鞭金藻和球等鞭金藻都为30%。化冻后,含绿色巴夫藻的胶球在培养基中22℃暗放置48h存活率最高;另两种藻在相对湿度为75%的气相中22℃暗放置12h存活率最高。在本实验条件下,绿色巴夫藻、湛江等鞭金藻和球等鞭金藻的冰冻保存的存活率可分别达到74%、15%和17%。 相似文献
52.
A series of hydraulic model tests has been carried out in a glass wave flume to investigate the influences of wave height, wave period, wave steepness, surf similarity parameter, roughness, layer thickness and porosity on wave run-up and overtopping of 1:2 sloped impermeable and permeable breakwaters fronted by a 1:10 gentle, smooth beach slope. The analysis of results involves the correlation between the overtopping energy transfer with the relative wall height and the relationship between wave run-up and overtopping rate. Further, measured wave run-up and overtopping rates are compared with the results given in the Shore Protection Manual (1984), Automated Coastal Engineering System (1992)and results of other investigators. 相似文献
53.
西洋东大港水道流速垂线分布研究 总被引:2,自引:0,他引:2
对辐射沙洲海域东大港4#站位连续2个潮周期的流速测量资料进行了分析、研究,拟合给出了流速垂线分布关系,并根据实际测量资料确定了该站位6个水层的浑水水流尾流函数项表达式。这些表达式表明浑水水流尾流函数是相对深度和摩阻速度的函数。探讨分析了尾流函数的空间分布和潮周期过程。非恒定流的水流尾流函数项的准确表达,对于揭示含沙水流流速结构及水、沙相影响作用规律将起到启发和推动作用。 相似文献
54.
A statistical model is developed to predict wave overtopping volume and rate of extreme waves on a fixed deck. The probability density function for the volume and rate of overtopping water are formulated based on the truncated Weibull distribution with the assumption of local sinusoidal profile for small amplitude waves. Sensitivity to the wave nonlinearity parameter and deck clearance is discussed. The statistical model is compared to laboratory data of the instantaneous free surface elevation measured in front of a fixed deck, and overtopping volume and overtopping rate measured at the leading edge of the deck. The statistical theory compared well with the measured exceedance probability seaward of the deck. The model prediction of the exceedance probability of deck overtopping gave qualitatively good agreement for large overtopping values. 相似文献
55.
56.
在实验室内, 22. 5±0. 5℃条件下以去头去骨去鳞片去皮的金色小沙丁鱼的纯肉糜为饵料饲养斜带髭鲷幼鱼,测定体重范围在 4. 6~6. 5g的斜带髭鲷的体重、体长的生长曲线及其生态转换效率和特定生长率.实验结果表明,斜带髭鲷的体重、体长在实验期间直线增长,体重、体长的生长曲线分别为Wt(w.w.湿重,下同 ) =0. 391 7t 5. 766 2(R=0. 999 6)和Lt=0. 105t 6. 265(R=0. 989 9).用胃含物法测定斜带髭鲷的胃排空率、日摄食量、日生长量、生态转换效率和特定生长率.实验得到斜带髭鲷消化道的瞬时排空率Rt= 1. 23 4×10-3 (m/m) /h,日摄食量Cd= 1. 342 9g(w.w. ),生态转换效率Eg=29. 50% ±2. 77% [m/m(w.w. ) ],特定生长率SGR=4. 71%±0. 69% [m/m(w.w. ) ]. 相似文献
57.
Application of LICOM to the numerical study of the water exchangebetween the South China Sea and its adjacent oceans 总被引:8,自引:1,他引:8
1 IntroductionThe South China Sea (SCS) is the largestmarginal sea in the western Pacific (see Fig. 1). It con-nects with the SCS through the Taiwan Strait, with thePacific through the Luzon Strait, with the Sulu Seathrough the Mindoro and Balabac Straits and with theJava Sea and Andaman Sea through the Sunda Shelf(For convenience, here we refer to the section at 1.5°N,Fig. 2). It is shown that the seasonal SCS circulation ismostly affected by the summer/winter monsoon, andthe no… 相似文献
58.
Yoichi?ShimadaEmail author Atsushi?Kubokawa Kay?I.?Ohshima 《Journal of Oceanography》2005,61(5):913-920
Recent observations suggest that the annual mean southward transport of the East Sakhalin Current (ESC) is significantly larger
than the annual mean Sverdrup transport. Motivated by this observational result, transport of a western boundary current has
been investigated using a simple numerical model with a western slope. This transport is defined as the instantaneous barotropic
transport integrated from the western boundary to the offshore point where the barotropic velocity vanishes. The model, forced
by seasonally varying wind stress, exhibits an annual mean of the western boundary current transport that is larger than that
of the Sverdrup transport, as observed. The southward transport from October to March in the model nearly equals the instantaneous
Sverdrup transport, while the southward transport from April to September decreases slowly. Although the Sverdrup transport
in July vanishes, the southward transport in summer nearly maintains the annual mean Sverdrup transport, because the barotropic
Rossby wave cannot intrude on the western slope. This summer transport causes the larger annual mean. Although there are some
uncertainties in the estimation of the Sverdrup transport in the Sea of Okhotsk, the seasonal variation of the southward transport
in the model is qualitatively similar to the observations. 相似文献
59.
You Yuming Hou Min Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Assistant Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1992,(3)
- The data of landsat TM of multi-temporal for Lingdingyang Estuary, Pearl River in China is firstly used with suspended sediment concentration of field measurement to establish a correlative model equation. After the ratio processing of TM data and atmospheric correction, the images of suspended sediment concentration of different temporals are exported from the image processing systems AREIS II and III. These images express the characteristics of suspended sediment distribution, the mode of sediment transport and the extent of dispersion under the actions of tidal current and wind condition of different seasons. 相似文献
60.
太平洋海域海平面变化的灰色系统分析 总被引:3,自引:1,他引:3
应用灰色系统理论,对太平洋海域48个长期验潮站的月均海平面分别建立了GM(1,1)模型。GM(1,1)模型能较好地反映太平洋海域的海平面变化的趋势,它除了能给出连续的海平面变化速率外,同时能方便地给出海平面变化的加速率。模拟结果表明,在太平洋地壳均衡假设下,太平洋海域的月均海平面以平均速率0.17cm/a上升。在太平洋海域所取的48个长期验潮站中,有40个站在加速上升,全部站的平均加速度为0.00029cm/a2。且加速率逐渐增大。当然这些加速率都很小,但作为一种普遍性的趋势,这已足以说明:太平洋海域的海平面在加速上升 相似文献