长江口与杭州湾风暴潮三维数值模拟

基于改进的河口海岸和海洋三维数值模式ECOM-si，加入台风模型气压场和模型风场，同时考虑径流、天文潮与风暴潮耦合作用，数值模拟了TC9711（Winnie），TC0012（Prapiroon）和TC0014（Saomai）三个台风期间长江口和杭州湾的水位过程.与观测资料比较，模式较好地再现了台风期间的水位过程，采用Fujita（藤田）气压场公式计算的结果比Fujita Takahashi（藤田 高桥）气压场公式下的计算结果更符合实测值，并在上述3个台风期间计算水位值与观测值的均方误差分别为42.5 cm，41.7 cm，35.5 cm.     

氧化铝模板法控制合成一维梯度直径铋纳米线

功能梯度材料(FGM)是一类在材料构成要素上从一侧向另一侧呈逐渐变化,进而获得性能相应于组成和结构的变化而变化的非均质复合材料.但是,现有的材料制备技术很难达到组成和结构的连续梯度变化,从而很难达到所设计的梯度性能,这大大限制了功能梯度材料的发展和推广应用.然而纳米     

化学镀Fe-Zn合金镀层的耐腐蚀性能研究

研究了化学镀Fe-Zn合金镀层在10%的NaOH溶液与3.5%的NaCl溶液中的耐腐蚀性能.研究表明,在碱性环境中,镀层的耐腐蚀性能明显优于在NaCl中的耐腐蚀性能.镀层中Zn含量比较高时,镀层在NaCl中的耐腐蚀性较好,而Fe含量较高时,镀层在NaOH中的耐腐蚀性较好.Fe-Zn镀层在这两种腐蚀液中的耐腐蚀性能明显优于其它Fe基镀层.     

Field-aligned current distribution and response to interplanetary conditions during a superstorm―CHAMP observation

With geomagnetic measurements on board of CHAMP satellite, the characteristics of global large-scale field-aligned currents （FACs） in the topside ionosphere are investigated along with their responses to interplanetary conditions for the superstorm of November, 2003. It is found that （1） The storm-time FAC densities enhanced greatly in comparison with quiet period and the enhancements show hemispheric asymmetry of both summer-winter and sunlit-dark. （2） For the first time, it is revealed that the lati- tude-integrated FAC density is controlled mainly by solar wind dynamic pressure rather than iMF. （3） FACs expanded equatorward dramatically, with the lowest latitude being 45° MLat or more; on the dayside this expansion was controlled directly by IMF Bz, showing an interaction time scale of about 25 min in the solar wind-magnetosphere-ionosphere coupling system, and a nonlinear saturation of the equatorward expansion when IMF Bz 〈 -30 nT; while on the nightside, the expansion and recovery lagged about 3 h behind the IMF changes but nearly in phase with changes of SYM-H index. （4） During the storm main phase, the nightside FAC latitude coverage extended to 25° or wider, appearing multi-sheet current structure with more than 10 sheets.     

沉积方式对HfO2薄膜激光损伤阈值的影响

分别采用电子束蒸镀、离子束辅助沉积、离子束反应辅助沉积、双离子束溅射技术制备了二氧化铪薄膜,研究了薄膜的光学特性、缺陷、残余应力、弱吸收和抗激光损伤阈值.发现离子束反应辅助沉积的二氧化铪薄膜具有低的缺陷密度和高的损伤阈值;双离子束溅射的二氧化铪薄膜具有高的折射率、高的残余应力和低的损伤阈值.对二氧化铪薄膜的损伤阈值与上述特性之间的依赖关系进行了讨论,发现残余应力是影响薄膜抗激光损伤阈值的一个重要原因.     

Rationalization and Mechanisms of Pulsed Laser Deposition of Fibroin Nanofilms by Using Autogenous Binder

1 Results Homogeneity of fibroin thin films by pulsed laser deposition (PLD) was significantly improved by introducing autogenous binders to consolidate and homogenize the irradiation targets.Homogenization includes among others,decreases in the size of nanostructural units and the fractional debris.Simultaneously,the deposition rate was substantially increased.Autogenous binders are prepared via degumming and liquefaction of fibroin by using Na2CO3 and LiBr,respectively.We also found that optically hom...     

聚对亚苯基二亚甲基的化学气相沉积聚合

用化学气相沉积(CVD)聚合法制备了聚对亚苯基二亚甲基(PPX)膜,由傅立叶变换红外光谱(FTIR)图证实了其化学结构.采用热重分析(TGA)研究了PPX的热降解性能,结果表明,在空气氛围中由于氧气的参与,其热稳定性比在N2中差,热氧化降解明显.PPX具有较好的耐溶剂性和抗化学氧化性能,膜的吸水速率和吸水率也比较小,常温常压下3 h后才能达到吸水平衡.PPX膜的水汽渗透率随温度和湿度的升高而升高,用Arrhenius方程拟合可计算得到水汽在膜中渗透扩散的表观活化能为12.4 kJ.mol-1.PPX膜的动态力学温度谱表现出典型的结晶聚合物的行为,晶区中的次级转变造成了PPX在玻璃化转变后,随温度提高损耗因子出现的反常升高,以及储能模量的持续、平缓下降,而不同于非晶聚合物的突然下降.     

脉冲激光沉积GaN薄膜

采用脉冲激光沉积技术,在Al2O3（0001）衬底上生长GaN薄膜,利用X射线衍射（XRD）、原子力显微镜（AFM）研究了不同沉积温度,不同沉积压强对所生长的GaN薄膜晶体结构特征的影响.研究表明,沉积温度影响GaN薄膜结构,在700～750℃沉积范围内随温度升高,所沉积生长的GaN薄膜具有良好的结晶质量.在5～10Pa沉积气压范围内,提高气压有利提高GaN薄膜的结晶质量.     

Speciation of the elements and compositions on the surfaces of dust storm particles： The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in Beijing and Inner Mongolia was studied by XPS. The major species of iron on the surface were oxides, sulfate, silicate,FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3 are the main components of Si and Al on the surface respectively.One of the most important findings was that the Fe(Ⅱ) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4)3,one of the Fe(Ⅲ) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe enriched on the surface of aerosol particles. Fe(Ⅱ) accounted for 1.3%-5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to support the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.     

Synthesis of carbon nanotube arrays using ethanol in porous anodic aluminum oxide template

Carbon nanotube (CNT) arrays confined by porous anodic aluminum oxide (AAO) template were synthesized using ethanol as reactant carbon source at low pressure. Images by scanning electron microscope (SEM) and low magnification transmission electron microscopy (TEM) show that these CNTs have highly uniform outer diameter and length, absolutely controlled by the diameter and depth of nano-channel arrays of the AAO. High resolution transmission electron microscopy (HRTEM) imaging indicates that the graphitization of the CNT walls is better than the results reported on this kind of template-based CNT arrays, although it is not so good as that of multiwalled carbon nanotubes (MWCNTs) synthesized by catalysis. CNTs synthesized using acetylene as reactant gas show much less graphitization than those prepared using ethanol by comparing the results of HRTEM and Raman spectroscopy. The etchingeffects of decomposed OH radicals on the amorphous carbon and the roughness of AAO nano-channel arrays on the CNTs growth were employed to explain the graphitization and growth of the CNTs.