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781.
In this paper, tidal data of 19 years were analysed to obtain the harmonic constants of 472 constituents; yearly variations of the harmonic constants of some constituents for 19 years were also examined.We have also derived the formulae of response analysis by using another approach, and calculated 161 response weights of astronomical tides, solar radiational tides and nonlinear tides for 10 stations. Some significant results were obtained.  相似文献   
782.
By means of the proposed nonlinear diagnostic dynamic model for the planetary boundary layer (PBL) wind field, an introduction is given to the MOD method for wind prediction. Based on the MOD experiments on the surface wind field over the Northern Pacific Ocean from April to October 1985, it is concluded that the nonlinear diagnostic dynamic model used is better than the linear one.  相似文献   
783.
采用聚丙烯酰胺凝胶垂直平板电泳方法,研究分析了口虾蛄(Oratosquilla oratoria)肌肉、眼球、腹鳃、心脏和肝胰腺5种器官或组织中LDH、ADH、MDH、SDH、MEP、POD、AMY、GDH、SCD、EST、GLDH和SOD共12种同工酶的表达情况。结果表明,口虾蛄同工酶的表达具有明显的组织特异性。对12种同工酶进行生化遗传分析,获得了基本酶谱。12种同工酶共记录出35个基因座位,其中11个基因座位Ldh-3、Adh-1、Sdh-2、Est-1、Est-2、Est-3、Mdh、Mep-7、Gldh-1、Gldh-2和Scd-1为多态,其多态座位比例为31.43%。  相似文献   
784.
785.
INTRODUCTIONTheSCSisthelargestmarginseainthewestoftheNorthPacificOcean .Theprevailingwindinwinterisnortheast,whileinsummeritissouthwest .Itisstilluncertainthathowthecirculationandtemperature -salinityfieldassociatewiththemonsoonforcingandaccompanywithseveralkindsofvariationsbeforeorafterthesummermonsoonburst .DuringSECMEXin 1 998,twointensiveobservationperiods (IOP)havebeencarriedoutntheSCS (Fig 1 ) :IOP1 ,from 1 0Aprilto 5May ;IOP2 ,from 1 2JunetoJuly 6 ,inordertounderstandthe…  相似文献   
786.
Over the past decades, many attempts have been made to generate useful bottom erosion models for the study of cohesive sediment movement. This study addresses some of the key questions involved in determining the functional relationship between erosion rate and bottom shear stress. Current, wave, and turbidity data were collected from a bottom mounted instrument array in a moderately energetic estuarine environment. The bottom shear stress was calculated from a wave–current interaction model. The erosion rate was derived from the observed sediment concentration using a vertical mixing model. Examination of the relationship between erosion rate and bottom stress showed that the erosion rate varied at intertidal frequency. When averaged over the tidal fluctuation, the erosion rate remained approximately constant at low stress, but increased sharply when the shear stress rose above a critical value. This suggests two-stage erosion. The bed has a layered structure, in which a thin layer of loose, high water content material overlies a more consolidated bed. The top layer of high water content material (fluff) was easily disturbed and re-suspended by tidal currents, but the consolidated bottom layer was eroded only under conditions of high shear stress.  相似文献   
787.
浅述多元数据处理的一种简化拟合形式及算法剖析   总被引:1,自引:1,他引:1  
在实际工程试验与研究中 ,多元数据处理经常遇到 ,根据 Weierstrass定理 ,采用多项式拟合是一种常见的数据处理方法。对于多元多项式的系数求解问题 ,可以归结为超定方程组的求解问题。该文以超定方程组的 SVD求解算法为核心 ,阐述了在工程实际中关于多元数据处理的一种应用方法 ,并尝试给出多元多项式拟合的一种简化方法  相似文献   
788.
海湾扇贝养殖群体遗传多样性的研究   总被引:13,自引:4,他引:13  
用等位基因酶的聚丙烯酰胺凝胶电泳技术,研究了大连沿岸不同生态环境条件下的大李家湾低排筏、大李家湾高排筏、凌水桥、棋盘磨4个海湾扇贝养殖群体的遗传多样性.在4个群体的7种等位基因酶和闭壳肌蛋白中均检测到了22个基因位点,各群体的多态位点比例分别为22.73%,22.73%,22.73%,18.18%(P≤0.95)和27.27%,27.27%,31.82%,36.36%(P≤0.99);杂合度观测值分别为0.064,0.071,0.075,0.069;Hardy-Weinberg平衡偏离指数分别为-0.068,-0.020,-0.032,-0.050;近交系数分别为0.568,0.565,0.487,0.550;位点等位基因有效数分别为1.102,1.109,1.143,1.122;遗传变异综合评价指数分别为0.0060,0.0071,0.0088,0.0073.海湾扇贝养殖群体遗传多样性总体水平较低,但在这4个群体中,凌水桥群体的遗传多样性水平最高,大李家湾高排筏和棋盘磨群体的遗传多样性水平较高,大李家湾低排筏群体遗传多样性水平最低.  相似文献   
789.
I. INTRODUCTION AHP resin is a new type of adsorbent and has been studied by the units concernedfor several years. There is little report about this work so far. AHP resin was synthesizedin aqueous phase with tetra-ethylene pentamine (TEPA), epichlorohydrin (ECH) andC-reagent as raw materials, and basic zinc carbonate (P_Z_n) and rubber solvent oil (120Gasoline) as pore-forming material. Compared with the technique of the amorphous lumpresin and that of the resin synthesized in oil phase, the new technique of resin synthesizedin aqueous phase manifests many advantages, such as raising the capacity of uranium-adsorption of the resin, simplifying the after-treatment process, reducing the cost, etc. Sea water, in which all kinds of cation and anion exist, is a system of electrolytes,and the concentrations of many ions are higher than the concentration of uranium for  相似文献   
790.
The 1982-1983 El Niño event is examined in comparison with the other El Niño events in 1949-1983. The relationships of subtropical high to the sea surface temperature (SST) show the important influence of the atter, which vaired with the characters of El Niño events.  相似文献   
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