Vertical mixing rate evaluation based on radium isotope distributions of Yellow Sea and East China Sea

在黄海和东海采样测定了水体中的镭同位素分布,用平流扩散模型描述镭同位素分布,最小二乘方法计算了垂直涡动扩散系数和上升流或下降流流速.结果给出北黄海中部、南黄海中部、浙江沿岸和台湾北部海域存在上升流,流速分别为0.46x10--(-3)CM·S--(-1)、0.17x10--(-3)~1.39x10--(-3)CM·S--(-1)、2.02x10--(-3)~3.04x10--(-3)CM·S--(-1)和1.06x10--(-3)~2.51x10--(-3)CM·S--(-1).北黄海中部和东海东北部存在下降流.流速分别为-2.30x10--(-3)CM·S--(-1)和-0.61x10--(-3)~-2.10x10--(-3)CM·S--(-1) .计算同时给出的垂直涡动扩散系数为5.84~48.2 CM--2·S--(-1),平均值为22.3 CM--2·S--(-1).北黄海和浙江沿岸上升流流速与文献的结果一致;北黄海中部存在下降流与文献的结论一致.本研究结果与文献结果一致是对所建立的方法的肯定,也是对文献研究结果的支持.Radium isotopes in the seawater of the Yellow Sea and the East China Sea (YSECS) were measured and their vertical distributions were described using an advection-diffusion model.Vertical eddy diffusion coefficients and advection velocities in the YSECS were calculated by fitting the distributions of radium isotopes in the seawater using least-square method.Results showed that upwellings occur in the middle of Northern and Southern Yellow Sea,coastal zone of Zhejiang,and Northeast of Taiwan.The current rates of upwellings are 0.46×10--(-3)cm·s--(-1), 0.17×10--(-3)～1.39×10--(-3)cm·s--(-1),2.02×10--(-3)～3.04×10--(-3)cm·s--(-1) and 1.06×10--(-3)～2.51× 10--(-3)cm·s--(-1) for above four sea areas respectively.Downwellings are indicated in the middle of Northern Yellow Sea and Northeastern East China Sea and the current rates are -2.30×10--(-3)cm·s--(-1) and -0.61×10--(-3)～-2.10×10--(-3)cm·s--(-1) respectively.The vertical eddy diffusion coefficients were obtained as 5.84～48.2 cm--2·s--(-1) with an average of 22.3 cm--2·s--(-1) from the same calculation.Upwelling velocity of Northern Yellow Sea and coastal zone of Zhejiang given by this study is in agreement with the results of literatures,and downwelling in Northern Yellow Sea is also supported by the literature.The agreement of the results obtained in this study with that of literatures not only confirms previous inference about upwelling distribution in the Yellow Sea and East China Sea,but also affirms the validity of our method.973计划项目(2005CB422305;2006CB400602)资

Biogenic silica in surface sediments of the northeastern and southern South China Sea

本研究测定了南海东北部和南部海域表层沉积物的生物硅含量(SIO2%),其含量范围分别为1.08%—3.01%和0.79%—9.06%,平均值分别为1.76%和4.22%。研究结果表明,南海表层沉积物中的生物硅含量与站位水深呈正相关关系;南海东北部的表层沉积物中的生物硅含量与其中的矿物含量、铁离子浓度、间隙水中的营养盐浓度不存在明显的相关性;南海南部海域表层沉积物中的生物硅含量与烧失量、有机碳含量、碳酸盐含量呈正相关关系,与粘土矿物含量相关性不明显。Biogenic silica(BSi) contents in surface sediments from the northeastern South China Sea(NSCS) and southern South China Sea(SSCS) were measured.The BSi contents(SiO2%)were in the range of 1.08%–3.01% and 0.79%–9.06%,with the means of 1.76% and 4.22% for the NSCS and SSCS,respectively.The results showed that the BSi contents in surface sediments have positive correlation with water depth of the sampling locations.The BSi contents in the NSCS had no evident correlation with minerals,ferrum ion concentrations in surface sediments or nutrients in the pore waters of sediments.The BSi contents in the SSCS had positive correlations with organic material and carbonate contents but not with clay material contents.国家基础研究发展计划项目(2005CB422305

Lattice Boltzmann Simulations of the Klinkenberg Effect in Porous Media

格子Boltzmann数值模拟方法是研究复杂的多孔介质结构特别是Klinkenberg效应的有效方法之一，对处理复杂边值问题尤其有效。用格子Boltzmann方法研究了气流穿越多孔介质问题，并将数值计算结果与实验结果进行了比较，结果表明格子Boltzmann方法是数值模拟气流穿越多孔介质问题的有效方法之一

--(226)Ra and --(228)Ra in seawater of the North Yellow Sea

用锰纤维富集-射气法测定了北黄海海水中的镭同位素226rA和228rA,研究了该海域水体中镭同位素的含量和分布.研究结果表明北黄海水体夏季226rA的比活度为1.80~4.35 bQ/M3,平均值为3.06 bQ/M3;冬季226rA的比活度为2.08~5.20 bQ/M3,平均值为3.28 bQ/M3.北黄海夏季228rA的比活度为3.85~25.60 bQ/M3,平均值为10.60 bQ/M3;冬季228rA的比活度为3.14~15.60bQ/M3,平均值为7.66 bQ/M3.该数据范围和中国近海其他海域、孟加拉湾、泰国昭披耶河口、濑户内海等海域相近.北黄海东北部海域,渤海海峡靠近山东半岛的海区和中北部海区表层镭同位素活度较高.C1断面镭同位素的分布特征从镭同位素的方面证实了渤海海峡水交换表现为北进南出特征这一结论的正确性.226rA和228rA的垂直分布较为复杂,大部分站位呈现出底层活度变高的趋势,其他少数站位呈现出中间层活度高的分布特征,不同来源的镭同位素输入至该海域形成了这样的分布特征.226Ra and 228Ra in the seawater of the North Yellow Sea were measured using the Mn-fiber adsorption-emanation method.The concentrations and distributions of 226Ra and 228Ra in this sea area were determined as follows: 226Ra activities were 1.80 to 4.35Bq/m3 with an average of 3.06Bq/m3 in the summer and 2.08 to 5.20Bq/m3 with an average of 3.28Bq/m3 in the winter;228Ra activities were 3.85 to 25.60 Bq/m3 with an average of 10.60Bq/m3 in the summer and 3.14 to 15.60Bq/m3 with an average of 7.66Bq/m3 in the winter.These concentration ranges for radium isotopes in the northern Yellow Sea were similar to those recorded for other sea areas of the China Seas,the Bay of Bengal,the Chao Phraya River Estuarine mixing zone of Thailand,the Seto Inland Sea and more.There were three areas of high radium isotope concentrations in the North Yellow Sea: the northeast area,the South Bohai Strait,and the central and the north area.The radium isotope distribution of section C1 confirmed the suggested movement of sea water into the Bohai Strait from the North and the exit of water from the Strait in the South.Vertical distributions of 226Ra and 228Ra were complex with higher activities exhibited in the bottom layers at most stations and in the middle layers at a few stations.This variable distribution pattern was due to input of radium isotopes from different sources.国家基础研究发展计划资助项目(2005CB422305

ZA蜗轮蜗杆的主动参数化精确3D数模设计

ZA型蜗轮蜗杆传动,其蜗轮齿面是复杂的蜗杆圆柱螺旋面的空间共轭曲面,蜗轮齿面数学方程描述复杂,参数化精确建模困难。依据蜗轮滚刀包络加工蜗轮齿面原理,协同运用CATIAV5平台的PDG、GSD、ASD、DMU SPA、DMU KIN 5个功能模块和knowledge工具,提出了用于ZA蜗轮齿面参数化精确数字建模的"以参控仿射曲线族为主导的多截面创成式复合构型方法",构建了拥有静、动态区域接触分析负反馈环节的主动可控参数化建模流程,为蜗轮蜗杆传动的高级CAE分析奠定了参数化精确3D数模基础

--(224)Ra in seawater of northern Yellow Sea

用锰纤维富集-射气法测量了北黄海水体的224rA,研究了该海域夏季和冬季2个季节224rA比活度及其垂直分布,并对其进行了比较研究.北黄海夏季224rA比活度为0.24~3.48bQ/M3,平均值为1.14bQ/M3;冬季224rA比活度为0.37~6.68bQ/M3,平均值为0.94bQ/M3.北黄海的表层水有3个224rA高值区,分别位于东北部海域、渤海海峡南部和北黄海中北部海区.30M水深将224rA比活度的垂直分布分成上层和下层2层.在0~30M水层,夏季,随着水深增加224rA比活度逐渐增加,比活度变化较小;冬季部分站位由表层向下224rA比活度逐渐降低.30M水深以下,224rA比活度随着水深的增加而增加,而且变化幅度较大.由224rA比活度的垂直分布得出该海域的垂直涡动扩散系数为2.5~43.5CM2/S,夏季北黄海冷水团中心海域底层溶解态化学物质输运补给到上层所经历的时间为9~15d左右.224Ra in seawater of northern Yellow Sea were measured using Mn-fiber adsorption-emanation method.The horizontal and vertical distribution of 224Ra in the sea in summer and winter were studied.The 224Ra activities were 0.24～3.48Bq/m3 with an average of 1.14Bq/m3 in summer and 0.37～6.68Bq/m3 with an average of 0.94Bq/m3 in winter.There were 3 high 224Ra areas in the northern Yellow Sea:northeast area,southern Bohai Strait,and central and northern area.30m layer divided the 224Ra vertical distribution into two parts:upper layer and lower layer.The upper layer,0～30m 224Ra increased with the depth and varied slightly in summer and 224Ra decreased with depth for some stations in winter.The layer below 30m,224Ra increased with depth and varied greatly.The vertical eddy diffusion coefficients based on the vertical distributions of 224Ra were 2.5～43.5cm2/s.It took 9～15d for the dissolved chemical matters in central area of the Yellow Sea cold water mass to transporte from the bottom layer to the upper layer in summer time.国家基础研究发展计划资助项目(2005CB422305

一种湖岸带生态修复的方法

本发明公开了一种湖岸带生态修复的方法，其特征在于：首先选择湖岸带水深的区域，划定范围；其次是选定种植植物；第三是设置植物行间距；第四是设置消浪层，固定木桩；第五是设置防浪层和浮动防浪层，在消浪层内侧打木桩，木桩上钉铁板制作防浪层，同时用泡沫制作浮动防浪层；第六设置挺水和沉水植物种植的位置；第七是维护。本发明方法简便，操作方便，投资成本低，种植植物成活率高，水体无污染，具有环境，社会和经济效益