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71.
本论文通过对南海北部三次台风过境期间基于浮标观测的海浪谱进行分析,发现虽然大部分成熟的台风海浪谱为单峰结构,但实际上在台风海浪的成长和衰减阶段,双峰谱占据了很大的比例。双峰谱的形成主要是由于风浪和涌浪的叠加以及不同波分量之间的非线性相互作用,我们可以通过能量密度的成长率对谱型变化进行高效的预报。此外,台风海浪的主要波向依赖于台风中心相对观测点的位置,而波向的分散情况在相距台风中心较远的区域无明显规律。本文提出了一个新的六参数波浪谱型拟合双峰谱,其拟合效果相较于前人的谱型更好。通过验证,形状参数和谱宽度之间的理论关系依然适用于单个谱峰。通过分析谱参量的变化特征,证明了谱参量不仅与台风强度和台风路径相关,还存在很强的交互相关。最后通过拟合海浪谱数据,本文得到了台风影响下海浪有效波高和有效周期之间的成长关系,这对海洋工程实际应用具有重要意义。 相似文献
72.
Based on in-situ observation, satellite and reanalysis data, responses of the western North Pacific subtropical ocean(WNPSO) to the slow-moving category 5 super typhoon Nanmadol in 2011 are analyzed. The dynamical response is dominated by near-inertial currents and Ekman currents with maximum amplitude of 0.39 m/s and 0.15 m/s, respectively. The near-inertial currents concentrated around 100 m below the sea surface and had an e-folding timescale of 4 days. The near-inertial energy propagated both upward and downward, and the vertical phase speed and wavelength were estimated to be 5 m/h and 175 m, respectively. The frequency of the near-inertial currents was blue-shifted near the surface and redshifted in ocean interior which may relate to wave propagation and/or background vorticity. The resultant surface cooling reaches -4.35℃ and happens when translation speed of Nanmadol is smaller than 3.0 m/s.When Nanmadol reaches super typhoon intensity, the cooling is less than 3.0℃ suggesting that the typhoon translation speed plays important roles as well as typhoon intensity in surface cooling. Upwelling induced by the slow-moving typhoon wind leads to typhoon track confined cooling area and the right-hand bias of cooling is slight. The mixed layer cooling and thermocline warming are induced by wind-generated upwelling and vertical entrainment. Vertical entrainment also led to mixed layer salinity increase and thermocline salinity decrease, however, mixed layer salinity decrease occurs at certain stations as well. Our results suggest that typhoon translation speed is a vital factor responsible for the oceanic thermohaline and dynamical responses, and the small Mach number(slow typhoon translation speed) facilitate development of Ekman current and upwelling. 相似文献
73.
Guoyan Ren Bafang Li Xue Zhao Yongliang Zhuang Mingyan Yan Hu Hou Xiukun Zhang Li Chen 《中国海洋大学学报(英文版)》2009,8(1):83-88
In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish (Rhopilema esculentum) oral-arms, a high performance liquid chromatography (HPLC)-assay for the determination of the TGP was developed. Purified
target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted
against concentration for TGP were linear (r = 0.9984, y = 4.5895x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction recovery was 97.84% (CV2.60%). The fractions
containing TGP were isolated from jellyfish (R. esculentum) oral-arms by four extraction methods: 1) water extraction (WE), 2) phosphate buffer solution (PBS) extraction (PE), 3) ultrasound-assisted
water extraction (UA-WE), 4) ultrasound-assisted PBS extraction (UA-PE). The lyophilized extract was dissolved in Milli-Q
water and analyzed directly on a short TSK-GEL G4000PWXL (7.8 mm×300 mm) column. Our results indicated that the UA-PE method
was the optimum extraction method selected by HPLC. 相似文献
74.
75.
淄博市淄川区治理私开滥挖工作经验 总被引:1,自引:1,他引:0
淄川区位于淄博市中部,是一个具有百年开采历史的工矿老区,全区面积1 000 km2,辖17个乡镇、3个街道、1个省级经济开发区,总人口67.3万人。境内矿产资源丰富、储量大、矿种多、分布广、埋藏浅、易开采以及综合利用价值高,已累计发现煤、铁、耐火黏土、陶瓷土、石灰石等矿种24种。截至2008年底,全区共有矿山企业126处,从业人员12 000余人,年产各类矿产品1 150余万吨,实现工业总产值84 000余万元,矿业为淄川区经济社会发展做出了重大贡献。但由于受经济利益驱动,私开滥挖曾一度屡禁不止,严重影响了正常开采,2008年底,淄川区被省政府列为资源枯竭型城市。 相似文献
76.
77.
Rossby waves with linear topography in barotropic fluids 总被引:1,自引:0,他引:1
Rossby waves are the most important waves in the atmosphere and ocean, and are parts of a large-scale system in fluid. The theory and observation show that, they satisfy quasi-geostrophic and quasi-static equilibrium approximations. In this paper, solitary Rossby waves induced by linear topography in barotropic fluids with a shear flow are studied. In order to simplify the problem, the topography is taken as a linear function of latitude variable y, then employing a weakly nonlinear method and a perturbation method, a KdV (Korteweg-de Vries) equation describing evolution of the amplitude of solitary Rossby waves induced by linear topography is derived. The results show that the variation of linear topography can induce the solitary Rossby waves in barotropic fluids with a shear flow, and extend the classical geophysical theory of fluid dynamics. 相似文献
78.
???????????????????????????????????????嶫?????????GPS????????????????????????????????λ??ó?????????β???????仯???????????2001???????8.1???????????β?????????д?????μ?仯????????仯?????????ж??????????С????????????????????????????????????????8.1????????????????????????????????о????????????????β???????п??????????????????? 相似文献
79.
1土地利用特点 泽市土地总面积121.94万hm2,已利用土地115.28万hm2,土地利用率为94.54%,农用土地97.99万hm2,占土地总面积的80.36%,其中耕地83.30万hm2,占土地总面积的.68.26%,园地1.22万hm2,占土地总面积的1.00%,林地6.38万hm2,占土地总面积的5.22%;其他农用地7.24万hm2,占土地总面积的5.88%;建设用地18.93万hm2,占土地总面积的15.52%;未利用土地5.35万hm2,占土地总面积的4.12%. 相似文献
80.
利用QuikSCAT/NCEP混合风场及WAVEWATCH模拟东中国海风浪场 总被引:7,自引:0,他引:7
将国际上比较成熟的海浪模式WAVEWATCH-Ⅲ移植到东中国海,采用QuikSCAT卫星遥感资料与NCEP数据混合风场作为强迫项,对该海区2000年1月23日至31日的一个大风天气过程下的风浪场进行了模拟计算。计算结果与浮标观测资料的对比结果说明,所获得的风浪场数值结果不但具有较高的时空分辨率,其精度也是比较高的。 相似文献