激发频率对高氢稀释下纳米晶硅薄膜生长特性的影响

利用等离子体增强化学气相沉积技术,在高氢稀释条件下,研究不同激发频率对纳米晶硅薄膜生长特性的影响.剖面透射电子显微镜(TEM)分析结果显示,不同激发频率下制备的纳米晶硅薄膜晶化区均呈锥状结构生长,但13.56 MHz激发频率下制备的纳米晶硅薄膜最初生长阶段存在非晶态孵化层,即纳米晶硅薄膜的形成经历了由非晶态孵化层到晶态结构层的转变.而高激发频率(40.68 MHz)下硅纳米晶则能直接在非晶态衬底上生长形成.Raman谱和红外吸收谱测量结果表明高激发频率(40.68 MHz)下制备的纳米晶硅薄膜不但具有较高     

非晶态Ni-S合金在碱液中析氢反应(HER)机理的研究

本文研究了非晶态 Ni- S合金的析氢反应机理。用稳态极化曲线研究非晶态 Ni- S合金的极化行为 ,得到其反应的动力学参数塔菲尔斜率和表观反应活化能。用断电流法和循环伏安法研究氢原子的吸附和中间态粒子。考察电极表面粗糙度、活性粒子表面吸附浓度等因素 ,综合分析得出 Ni- S合金电极具有高催化活性的原因及其 HER电催化机理     

相变存储材料Ge1Sb2Te4和Ge2Sb2Te5薄膜的结构和电学特性研究

采用射频磁控溅射方法制备了两种用于相变存储器的Ge₁Sb₂Te₄和Ge₂Sb₂Te₅相变薄膜材料,对其结构、电学输运性质和恒温下电阻随时间的变化关系进行了比较和分析.X射线衍射(XRD)和原子力显微镜(AFM)的结果表明:随着退火温度的升高,Ge₁Sb₂Te₄薄膜逐步晶化,由非晶态转变为多晶态,表面出现均匀的、     

太平洋北赤道逆流年际变化的特征及其影响因子分析

采用SODA数据资料,分析了1950—2008年太平洋北赤道逆流(NECC)的年际变化特征及其与ENSO循环的联系。研究结果表明:(1)El Nio(La Nia)盛期是NECC流量由年际异常增大(减小)到异常减小(增大)的转折点;(2)NECC流轴的纬度在El Nio(La Nia)盛期达到年际异常最南(北)端;(3)NECC流轴在深度上呈西深东浅倾斜,El Nio(La Nia)盛期倾斜最弱(强)。通过构造典型ENSO循环的海表面风应力场,驱动一层半线性约化重力数值模式,结果验证了在NECC的年际变化中海表面风应力场是关键因素,而大洋波动(Kelvin波和Rossby波)和洋流本身是海洋内部的主要动力调整机制。     

南海海面高度异常与厄尔尼诺和大气环流的关系

利用经验正交函数分解和相关分析等方法分析研究了南海和赤道太平洋的海面高度异常、海面温度异常和风异常之间的相关关系.得出南海海面高度异常EOF第一模态为ENSO模态,方差贡献达到44.7％.在厄尔尼诺(El Ni(n)o)期间,整个南海海面下降,SSHA呈现不同的分布状态,本文讨论了爆发与下半年的El Ni(n)o期间南海SSHA呈现的典型分布状态.El Ni(n)o的先兆阶段南海中部为SSHA低值区,鼎盛阶段南部SSHA增大形成南高北低的分布状态,恢复阶段SSHA分布与El Ni(n)o过后是否发生La Ni(n)a密切相关.南海海面高度异常与大气环流存在明显的相关关系.El Ni(n)o期间,Hadley环流的加强使得南海东部和赤道西太平洋水交换加强,水温的降低和海水的流失使南海海面下降,Walker环流结构和强度的变化则进一步促进了南海SSH的下降.El Ni(n)o期间,南海海面高度会较常年偏低.     

基于准连续介质方法模拟纳米多晶体Ni中裂纹的扩展

通过准连续介质方法模拟了纳米多晶体Ni中裂纹的扩展过程.模拟结果显示:裂纹尖端的应力场可以导致晶界分解、层错和变形孪晶的形成等塑性形变;在距离裂纹尖端越远的位置,变形孪晶越少;在裂纹尖端附近相同距离处,层错要远多于变形孪晶.这反映了局部应力的变化以及广义平面层错能对变形孪晶的影响.计算了裂纹尖端附近区域原子级局部静水应力的分布.计算结果表明:裂纹前端晶界处容易产生细微空洞,这些空洞附近为张应力集中区,并可能促使裂纹沿着晶界扩展.模拟结果定性地反映了纳米多晶体Ni中的裂纹扩展过程,并与相关实验结果符合得很好     

全球和南海海平面变化及其与厄尔尼诺的关系

利用卫星高度计资料,分析了1993年1月至2004年12月全球和南海的海平面变化特征.结果表明,在1993-2004年期间,全球和南海海平面的平均上升率分别为(2.5±0.2)mm/a 和(4.8±1.2)mm/a.研究发现,全球和南海海平面的低频变化都与 El Ni(n)o 密切相关,但二者对El Ni(n)o 的响应位相相反.1997-1998年 El Ni(n)o 初期,全球平均海平面升高,呈现正异常;El Ni(n)o 后期,全球平均海平面下降并由正异常变为负异常.南海平均海平面在 El Ni(n)o 期间呈现负异常,在 La Ni(n)a期间呈现正异常,其低频变化与南方涛动指数的低频分量位相变化几乎完全一致.ENSO 可以通过南海季风和北太平洋环流(黑潮)的变化来影响南海海平面.El Ni(n)o 发生前后的北风异常,以及同期黑潮流量的变化都对 ENSO 影响南海有一定的贡献.     

2009/2010年El Ni(n)o事件变化特征及其机理

应用TAO (Tropical Atmosphere Ocean project)热带太平洋实测海温和风场资料,分析研究了发生在2009/2010年的El Ni(n)o事件的变化特征,讨论了此次El Ni(n)o事件发生过程中,赤道东、西太平洋次表层异常海温的变化特征及其传播过程,特别是对赤道太平洋次表层异常海温变化的...     

九州-帕劳海脊南段铁锰结壳物质组成特征及成因机制

铁锰结壳(又称富钴结壳、多金属结壳)富含Co、Cu、Mn、Ni、Ti、V、REE、Y和Zn等人类日常生活和高新技术产业亟需的关键金属,是一种重要的战略性矿产资源。本文对九州-帕劳海脊南段水深1 900～2 600 m处获得的9个站位铁锰结壳样品进行了矿物学和地球化学研究,分析了铁锰结壳的矿物组成、主微量元素和稀土元素含量,并进一步探讨了铁锰结壳的成因类型。结果表明,研究区铁锰结壳的矿物组成以水羟锰矿为主,同时含有大量非晶态铁氧/氢氧化物;Mn、Fe、Co、Ni、Cu平均含量分别为16.15%、15.38%、0.32%、0.33%、0.10%;CaO/P₂O₅均值为5.93,表明九州-帕劳海脊南段铁锰结壳样品均未发生磷酸盐化作用;铁锰结壳明显富集稀土元素(含Y,REYs),平均含量为1 194μg/g,轻稀土显著富集,稀土元素经后太古代澳大利亚页岩(PAAS)标准化后配分模式整体相对平坦,呈现Ce正异常而Eu无异常,与海水呈现镜像关系,说明铁锰结壳稀土元素主要来源于海水。铁锰结壳的矿物组成和元素判别图均表明九州-帕劳海脊南段铁锰结壳属于水成型,...     

厄尔尼诺的发生与行星运动

厄尔尼诺(El Ni(?)o)现象是海-气耦合系统异常变化的表现,其起因可能不是唯一的,行星运动对地球运动的影响可能会导致El Ni(?)o的发生。根据4个半世纪内El Ni(?)o发生的历史资料,分析其发生和行星运动的关系,得出的结论是:木星赤纬的变化和火星大冲与El Ni(?)o。的发生有显著的关系,表明这2颗行星的运动可能影响El Ni(?)o的发生。文中还根据分析结桌和El Ni(?)o混沌机制的观点,探讨了行星运动对海-气系统变化的影响机制。     

高锰铝青铜焊缝在3.5%NaCl溶液中的空蚀行为

利用磁致伸缩空蚀实验装置对高锰铝青铜焊缝在质量分数为3．5％NaCl水溶液中的空蚀行为进行了研究。结果表明，焊接金属的抗空蚀性能明显高于母材，焊缝金属的空蚀累积失重及失重率均约为母材的1／4。SEM空蚀形貌分析表明，母材的空蚀破坏比焊缝金属严重得多，导致空蚀破坏的裂纹萌生于晶界。     

平台钢锈层的电子探针微束分析

利用电子探讨微束分析仪（ＥＰＭＡ）分析了平台合金钢腐蚀锈层的形貌特征及组成元素的分布。实验结果表明，不同的形貌特征以及不同含量的合金元素及其组合对平均腐蚀速度，尤其对局部腐蚀行为有一定的影响。组成元素如Ｍｎ，Ｃｒ，Ｃｕ和Ｎｉ在内锈层内富集，使内锈层更致密且与基体的附着性好，有效地阻止引起腐蚀的离子如Ｃｌ－，Ｓ２－，ＯＨ－，Ｍｇ２＋和Ｃａ２＋等向基体表面扩散，从而减低了腐蚀速度。     

南海S08-57站柱样岩心地球化学特征及古海洋学意义

对南海S08-57站柱样岩心的CaCO3、SiO2、Al2O3、TFe2O3、MgO、CaO、Na2O、K2O、TiO2、P2O5、MnO、Cu、Pb、Zn、Co、Ni、Ba、Sr、Rb、V、Cr、La、Ce和Ta的含量变化进行了分析;根据CaCO3含量变化建立了碳酸钙地层时标,提出了南海碳酸钙地层学的SB4.0事件,进一步完善了南海标准碳酸钙地层学时标;讨论了沉积物地球化学特征及古海洋学意义。结果表明,S08-57柱样岩心的SB3.33m事件附近存在一次强碳酸盐沉积,Al2O3、TiO2、Nb、SiO2、K2O、Ta、La、Rb、Ce、MgO、Zn、TFe2O3、Na2O、V、Pb和Cr的沉积曲线与CaCO3近似呈镜像关系。     

Accumulation and Cycle of Heavy Metals in Sonneratia apetala and S. caseolaris Mangrove Community at Futian of Shenzhen, China

Wetland ecosystem in the Shenzhen Bay is one of the internationally important ecosystems in South China Region. Its core, with the Mai Po Mangrove Nature Reserve in Hong Kong on the one side and the Futian Mangrove Nature Reserve in Shenzhen on the other side, provides habitats for many rare and endangered wild birds, especially for migratory birds[1, 2]. With the economic development in Hong Kong and Shenzhen, a large mount of silt and untreated waste water are poured into the Shenzhe…     

青海湖裸鲤的无机元素

１９８９年５月及１０月测定青海湖主要经济鱼类青海湖裸鲤Ｇｙｍｎｏｃｙｐｒｉｓ ｐｒｚｅｗａｌｓｋｉｉ ｐｒｚｅｗａｌｓｋｉｉ（Ｋｅｓｓｌｌｅｒ）不同性别，９种组织中的人体及动物必需常量元素６种，微量元素１０种的含量。存在不同组织、性别、季节及年份的差异。雌鱼常量元素总量是骨＞鳞＞鳃＞肝＞肌肉＞肠＞心＞卵巢＞皮；微量元素总量肠＞鳞＞心＞鳃＞骨＞肝＞皮＞卵巢＜肌肉。雄鱼常量元素总量是骨＞鳞＞鳃＞皮＞精     

The behavior of Zn,Cd, Cu,Ni, Co,Fe, and Mn in anoxic baltic waters

In June 1981, dissolved Zn, Cd, Cu, Ni, Co, Fe, and Mn were determined from two detailed profiles in anoxic Baltic waters (with extra data for Fe and Mn from August 1979). Dramatic changes across the O₂H₂S interface occur in the abundances of Cu, Co, Fe, and Mn (by factors of ?100). The concentrations of Zn, Cd, and Ni at the redox front decrease by factors between 3 to 5.Equilibrium calculations are presented for varying concentrations of hydrogen sulfide and compared with the field data. The study strongly supports the assumption that the solubility of Zn, Cd, Cu, and Ni is greatly enhanced and controlled by the formation of bisulfide and(or) polysulfide complexes. Differences between predicted and measured concentrations of these elements are mainly evident at lower ΣH₂S concentrations.Cobalt proved to be very mobile in anoxic regions, and the results indicate that the concentrations are limited by CoS precipitation. The iron (Fe²⁺) and manganese (Mn²⁺) distribution in sulfide-containing waters is controlled by total flux from sediment-water interfaces rather than by equilibrium concentrations of their solid phases (FeS and MnCO₃). The concentrations of these metals are therefore expected to increase with prolonged stagnation periods in the basin.     

Comparison of sinking particles in the upper 200 m between subarctic station K2 and subtropical station S1 based on drifting sediment trap experiments

Drifting sediment trap experiments were conducted during various seasons to elucidate the characteristics of particles sinking through the upper 200 m of the water column in the western Pacific at subarctic station K2 and subtropical station S1. The sinking particle flux increased when primary productivity was high at each station, during June–July at K2 and during February at S1. Biogenic opal (Opal) and CaCO₃ were the major components of the fluxes at K2 and S1, respectively. Contrary to the expectation of a high flux at the eutrophic station K2 and low flux at the oligotrophic station S1, the annual average organic carbon fluxes at 100 m were comparable at both stations: 62.7 mg C m^?2 day^?1 at K2 and 56.1 mg C m^?2 day^?1 at S1. The similarity of the fluxes was perhaps a reflection of the unexpectedly high primary production at S1. At K2, the organic carbon export ratio (organic carbon flux/primary productivity) was significantly and negatively correlated with primary production and tended to decrease with depth. The magnitude of the rate of attenuation of the organic carbon flux with depth was larger at S1 than at K2. This rate of attenuation tended to decrease and increase with primary production at K2 and S1, respectively. The explanation for these patterns may be that the flux of labile organic carbon at relatively shallow depths decreased with increasing primary production at K2, and zooplankton grazing pressure increased with increasing primary productivity at S1.     

Impacts of the wintertime mesozooplankton community to downward carbon flux in the subarctic and subtropical Pacific Oceans

We compared wintertime depth distributions of the mesozooplankton community and dominant copepods between the subtropical (S1) and subarctic (K2) Pacific Oceans to evaluate the relative importance of actively transported carbon by vertical migrants to sinking particulate organic carbon flux. Primary production was higher and the ratio of sinking particulate organic carbon flux to primary production was lower at S1 compared with those at K2. The mesozooplankton community was lower in abundance and biomass at S1 compared to K2. Copepods were the dominant group among both mesozooplankton abundance and biomass throughout the water column down to 1000 m at both sites. The depth distribution showed that diel vertical migration was obvious for the mesozooplankton abundance and biomass at S1 but was not apparent for the abundance at K2, because the dominant component was diurnally migrating species at S1 and overwintering species residing at mesopelagic depths at K2. The major components of diel migrants were copepods and euphausiids at S1 and only euphausiids at K2. Respiratory flux by the diurnally migrating mesozooplankton was estimated to be 2 mgC m⁻² day⁻¹ at S1 and 7 mgC m⁻² day⁻¹ at K2. The respiratory flux was equivalent to 131% of sedimentary fecal pellet flux at S1 and 136% of that at K2. Because pathways of downward carbon flux are facilitated by the mesozooplankton community, the actively transported carbon (respiration of dissolved inorganic carbon, excretion of dissolved organic carbon and egestion of fecal pellets at depth) might be larger during winter than the flux of sinking fecal pellets.     

印度洋波浪诱导的水体输运效应及其对赤道SST异常的影响

波浪诱导的水体输运会对海洋产生大尺度影响。结合波浪大尺度效应的研究现状和印度洋涌浪分布的事实,利用ECMWF-CERA20的波浪、海表面温度(SST)及风场数据,采用多种统计分析方法,研究了波浪输运与赤道印度洋SST的潜在关系。结果显示:中高纬度波浪输运异常的低频信号在空间、周期上与赤道SST异常均有高度相似性;Stokes漂流纬向、经向异常呈现出南—北、东—西的振荡,其第二模态时间序列与印度洋偶极子(Indian Ocean Dipole,IOD)指数存在强相关性并在La Ni a次年的负IOD事件中达到最高:相关系数在ACC区域纬向异常超前6个月时接近0.6,中纬度区域经向异常在超前3个月时达到0.7。在La Ni a次年的负IOD中,波浪经向输运异常的相位(超前三个月)与赤道SST异常相位呈全年反相位,经向浪致输运异常造成的东—西热量输运差异对赤道SST异常分布有不可忽略的贡献。     

Thermodynamic Analysis of Heavy Metals Biosorption by Two Macroalgae

The thermodynamic process of two macroalgae, Sargassum fusiforme and Lamin aria japonica, absorbing heavy, metal ions Cu^2 , Pb^2 , Cd^2 and Ni^2 . has been studied. The result indicates that the absorption isotherms of these two macroalgae clearly accord with the Landmuir adsorption model. The absorptive processes of S. fusiforme and L. japonica for Cu^2 are endothermal, and at 35℃, the adsorption heat of these two algae is 59.5kJ/mol and 76.8 kJ/mol respectively. Temperature could affect the algae‘s adsorption capacity. Their adsorption capacity increases with temperature (25℃ and 35℃).