In-situ STM Studies in BMIBF4 Room Temperature Ionic Liquid

非氯化铝室温离子液体作为一类新型反应介质是当前备受关注的多学科交叉前沿研究领域之一，其具有的宽电化学窗口和极低的蒸汽压对于扩大电沉积体系、制备功能性纳米材料具有重要的应用价值。本论文以自行合成的1－丁基－3－甲基咪唑四氟硼酸盐(BMIBF4)室温离子液体为介质，研究其电化学行为及该离子液体中的电化学沉积。主要研究内容和结果如下： 1．研究了Au(111)电极在纯BMIBF4液体中的电化学行为，并联合运用现场STM、SERS等技术研究了离子液体中电极/溶液界面结构随电位的变化，探讨了离子液体与电极表面的相互作用。研究表明，在BMIBF4中Au(111)电极表面随电位发生不同于Au(111)(&...Non-chloroaluminumated room temperature ionic liquids have received much attention as a new type of reaction media in advanced interdisciplinary research. With the wide electrochemical windows, negligible vapor pressures and high ionic conductivities, ionic liquids have been of great importance in expanding the electrodeposition systems and in the fabrication of functional nano-materials. In this ...学位：理学硕士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：20002505

Preparation of Dendritic Pt Thin Films and Their Anomalous Infrared Effects

采用方波电位,在10x10-3MOl·l-1k2PTCl6+3x10-4MOl·l-1PbAC2+0.5MOl·l-1HClO4溶液中,于本体PT电极上电沉积制备出枝晶状PT薄膜.随着沉积时间的增加,枝晶长度逐渐由400nM增加到900nM,且枝晶上的小晶粒(--10nM大小)变得密集.根据循环伏安(CV)曲线中氢吸脱附电量可得出PT薄膜具有中等粗糙度(Cr=9-36),且电极表面的粗糙度随着沉积时间增加而增大.观察到PT薄膜上吸附态CO的原位红外光谱具有明显的增强吸收效应,当沉积时间为6MIn时所制得的枝晶PT电极的红外增强效应最大.CO呈现多种谱峰形状,随着沉积时间的增加,谱峰形状依次为左高右低的双极峰(类fAnO红外效应),单极向下(表面增强红外吸收),左高右低的双极峰,单极向上(异常红外效应),左低右高的双极峰和单极向下.这表明纳米材料薄膜所呈现出的特殊红外性能,与纳米材料的尺度和聚集状态等密切相关.所制备的枝晶状PT薄膜有望为深入认识纳米材料的特殊红外性能提供一个良好的模型材料.Dendritic Pt thin films are electrodeposited on bulk Pt electrodes in 10×10 -3 mol · L -1 K 2 PtCl 6 +3× 10 -4 mol · L -1 PbAc 2 + 0.5 mol · L -1 HClO 4 using square-wave potential pulses.As the deposition time increases, the length of the Pt dendrites increases from 400 to 900 nm, and the distribution density of Pt nanoparticles (--10 nm), which consist of coiled Pt dendrites, increases greatly.From hydrogen adsorption/ desorption obtained from cyclic voltammograms (CV), the surface of the dendritic Pt thin film electrodes has a relative roughness (C r ), which increases from 9 to 36 as the deposition time increases.Maximum enhanced IR absorption of adsorbed CO (CO ad ) is observed at the deposition time of 6 min.Anomalous infrared effects for CO ad are also seen on the dendritic Pt thin film electrodes.The line shapes of CO ad change with increasing deposition time, in order: bipolar→downward→bipolar→upward→bipolar→ downward bands.Fano-like infrared effects (bipolar), surface enhanced IR absorption (enhanced downward band), and abnormal IR effects (enhanced upward band) are highly dependent on the surface architecture of the nanostructures.The as-prepared dendritic Pt thin films provide model substrates for in-depth studies of the anomalous infrared effects of CO ad in metal nanostructures.国家自然科学基金(21073152;20933004;20833005;21021002);福建省高校杰出青年科研人才培育计划(JA10003)资助项目---

Raman and AFM Characterization of Au and Cu Nanorod and Nanowire Arrays

通过电化学氧化法制备具有不同孔径氧化铝模板 ,利用交流电镀的方法在模板中沉积金属 ,再用酸溶解模板可以得到相应尺度的金属纳米线或纳米棒的阵列 .本文利用原子力显微镜和表面增强拉曼技术分别表征了金和铜两种金属纳米线阵列 .研究结果表明 ,作为探针分子的硫氰(SCN )在金属纳米线上的碳氮三键的振动频率随纳米线直径的增大而蓝移 .这一现象可能是因为尺寸效应对纳米线的费米能级造成影响 ,使不同直径的金属纳米线电子结构存在微小的差别 .Recently metal nanowires (nanorods) have aroused tremendous interest because of their novel properties and potential applications in wide fields [1] . Many two?dimensional nanowire arrays of semiconductors and metals with different diameter and length have been made by using template synthesis method. To characterize the novel optical, electronic and magnetic properties of these materials, UV?Vis and fluorescence spectroscopies are two of the most wildly used methods [2, 3] . Raman spectroscopy has, however, only been applied to the characterizing of semiconductor nanowires and carbon nanotubes [4,5] . Important and meaningful information can be obtained in these cases, as some forbidden Raman modes in the bulk materials become Raman active [4, 5] . Raman spectroscopy is apparently not suitable to study metal nanowires since it can only detect the mechanical vibration bands located in the extremely low frequency region. Consequently, an alternative way has to be established to study the metal nano?wires (?rods) with Raman spectroscopy. In the present work, we have taken the probe molecule strategy and used surface?enhanced Raman spectroscopy (SERS) to characterize metal nanorods (nanowires). It is well known that for a molecule which interacts strongly with a surface, its vibrational band frequency and shape are very sensitive to the electronic property, the chemical environment and the morphology of the surface. Hence Raman spectroscopy has long been used to analyze the atomic structures and the electronic properties of the surface indirectly through assessing carefully the spectral changes of the adsorbate known as a probe molecule. On that account, it is of great interest to diagnose the electronic structures of the metal nanorods with the vibrational spectrum of a probe molecule. We have examined the changes in the electronic properties of the nanorods through analyzing the spectral changes of the probe molecule. For this purpose a typical SERS molecule of SCN - was employed. The nanorod arrays of Au and Cu with different diameter from about 15 nm to 130 nm were fabricated electrochemically by means of the anodic aluminum oxide (AAO) templates. To partially expose metal nanowires with various lengths, the AAO template was chemically etched off to a certain extent by an aqueous solution of phosphoric acid or sodium hydroxide as shown in Fig. 1. After the template was etched off, the nanowires can be characterized by TEM, see Fig. 2. The tapping mode AFM image was obtained on a scanning probe microscope (Nanoscope IIIa). SERS measurements were performed on a confocal microprobe Raman system (LabRam I).作者联系地址：厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,南京师范大学化学系!江苏南京,210097,厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,厦门大学固体表面物理化学国家重点实验室!Author's Address: State Key Lab.for Phys.Chem.of Solid Surf.,Xiamen Univ.,Xiamen 361005, China; 1 Dept. of Chem., Nanjing Norm

中国物理海洋学研究70年：发展历程、学术成就概览

本文概略评述新中国成立70年来物理海洋学各分支研究领域的发展历程和若干学术成就。中国物理海洋学研究起步于海浪、潮汐、近海环流与水团,以及以风暴潮为主的海洋气象灾害的研究。随着国力的增强,研究领域不断拓展,涌现了大量具有广泛影响力的研究成果,其中包括:提出了被国际广泛采用的"普遍风浪谱"和"涌浪谱",发展了第三代海浪数值模式;提出了"准调和分析方法"和"潮汐潮流永久预报"等潮汐潮流的分析和预报方法;发现并命名了"棉兰老潜流",揭示了东海黑潮的多核结构及其多尺度变异机理等,系统描述了太平洋西边界流系;提出了印度尼西亚贯穿流的南海分支(或称南海贯穿流);不断完善了中国近海陆架环流系统,在南海环流、黑潮及其分支、台湾暖流、闽浙沿岸流、黄海冷水团环流、黄海暖流、渤海环流,以及陆架波方面均取得了深刻的认识;从大气桥和海洋桥两个方面对太平洋–印度洋–大西洋洋际相互作用进行了系统的总结;发展了浅海水团的研究方法,基本摸清了中国近海水团的分布和消长特征与机制,在大洋和极地水团分布及运动研究方面也做出了重要贡献;阐明了南海中尺度涡的宏观特征和生成机制,揭示了中尺度涡的三维结构,定量评估了其全球物质与能量输运能力;基本摸清了中国近海海洋锋的空间分布和季节变化特征,提出了地形、正压不稳定和斜压不稳定等锋面动力学机制;构建了"南海内波潜标观测网",实现了对内波生成–演变–消亡全过程机理的系统认识;发展了湍流的剪切不稳定理论,提出了海流"边缘不稳定"的概念,开发了海洋湍流模式,提出了湍流混合参数化的新方法等;在海洋内部混合机制和能量来源方面取得了新的认识,并阐述了混合对海洋深层环流、营养物质输运等过程的影响;研发了全球浪–潮–流耦合模式,推出一系列海洋与气候模式;发展了可同化主要海洋观测数据的海洋数据同化系统和用于ENSO预报的耦合同化系统;建立了达到国际水准的非地转(水槽/水池)和地转(旋转平台)物理模型实验平台;发展了ENSO预报的误差分析方法,建立了海洋和气候系统年代际变化的理论体系,揭示了中深层海洋对全球气候变化的响应;初步建成了中国近海海洋观测网;持续开展南北极调查研究;建立了台风、风暴潮、巨浪和海啸的业务化预报系统,为中国气象减灾提供保障;突破了国外的海洋技术封锁,研发了万米水深的深水水听器和海洋光学特性系列测量仪器;建立了溢油、危险化学品漂移扩散等预测模型,为伴随海洋资源开发所带来的风险事故的应急处理和预警预报提供科学支撑。文中引用的大量学术成果文献(每位第一作者优选不超过3篇)显示,经过70年的发展,中国物理海洋学研究培养了一支实力雄厚的科研队伍,这是最宝贵的成果。这支队伍必将成为中国物理海洋学研究攀登新高峰的主力军

Electrochemical Corrosion Behavior of TiO_2/HA Composite Coating on Medical Titanium in Tyrode s Physiological Solution

通讯作者，Tel:(86-592)2189354，E-mail:cjlin@ xmu.edu.cn[中文文摘]钛及其合金具有良好的力学性能和生物相容性,被广泛地用作医用人工植入体.然而,钛植入体在人体内的生理环境中必然发生腐蚀,金属离子的溶出和积累可产生毒副作用.本文应用电化学方法对医用钛金属作表面改性,提高其生物活性,应用Tafel极化曲线和电化学阻抗(EIS)研究其耐蚀性能及腐蚀电化学行为.结果表明,在钛基TiO2纳米管阵列膜层上沉积构筑HA涂层之后,由于表面阻挡层的强化,TiO2涂层在Tyrode’s生理溶液中的耐蚀性有所提高.[英文文摘]Titanium and its alloys have been widely used as medical implant materials because of their good mechanical properties and biocompatibility. However，the physiological corrosion of metal will release metal ions，resulting in toxic and side effects. In this paper，in order to improve the corrosion resistance of titanium，and to enhance its bioactivity and osseointegration，the surface modification of titamum were performed. Using eletrochemical methods Tafel polarization and electrochemical impedance spectroscopy (EIS) were applied to study the electrochemical corrosion behavior of TiO2 /HA composite coating. It is indicated that the corrosion resistance of the prepared TiO2 /Ti material in Tyrode＇s physiological solution is improved because of the enhanced surface barrier.国家自然科学基金(20773100)项目资

In-situ STM study of Sn UPD on Cu(111)electrode

本文用现场扫描隧道显微镜 (in situSTM)研究Sn在Cu( 1 1 1 )上的欠电位沉积 (underpotentialdepositionUPD)过程。实验结果表明 ,Sn原子在Cu( 1 1 1 )表面上的UPD首先在晶面的边缘处发生 ,随后向晶面的其余地方发展并取代吸附在表面的SO2 -4 ,这一过程伴随着显著的台阶轮廓的变化。在Sn的UPD层溶出过程中 ,台阶边缘形状发生了更剧烈的变化 ,并且观察到凹洞的出现 ,表明Sn与Cu( 1 1 1 )基底形成了表面合金The underpotential deposition(UPD)of Sn on Cu(111)has been investigated in H 2SO 4 solution using in situ scanning tunneling microscopy(STM). The experimental results indicated that UPD of Sn initializes at the edge of the terraces following the nucleation and growth model and grew towards to the center of the terraces until a submonolayer of Sn was formed. This process was accompanied by the change of the profile of the steps. Pits were observed at the surface after the dissolution of the UPD Sn indicating that the surface alloy has been formed between Cu and UPD Sn.国家自然科学基金资助项目 (No .2 98330 6 0 ,2 99730 34)~

煤与生物油的成浆性能研究

利用不同煤种的煤和生物油制备了不同浓度的生物油煤浆,考察了生物油煤浆的成浆浓度、表观黏度、流变特性和稳定性。结果表明,生物油煤浆是具有一定屈服应力的非牛顿流体,其流变特性可用宾汉姆方程来描述;生物油煤浆的屈服应力和表观黏度都随着固体浓度的增加而增大;随着剪切速率的增加,生物油煤浆的表观黏度减小;四种煤中,无烟煤的成浆浓度最高,可达42%,其含碳量高达49%,相当于同种煤制成的74%的水煤浆含量。烟煤次之,褐煤最低;生物油与煤粉之间能够形成絮凝性的大分子网络结构,使得生物油煤浆存在屈服应力并能够保持良好的静态稳定性,4.0～5.0 d天没有软沉淀产生,数月没有硬沉淀产生

碱法钛白清洁生产工艺中循环碱液的杂质分离

研究了碱法钛白清洁生产工艺循环碱液中关键组分锰、硅、铝的去除方法，考察了添加剂用量、反应温度等对去除杂质离子的影响。结果表明，当反应温度为90℃、还原剂与碱液体积比为1：200时，Mn（Ⅵ）的去除率可达到99.7％；在70-90℃之间，添加适量CaO，可将碱液中铝含量（以Al2O3计）由10.03g／L降至1g／L，将硅含量（以SiO2计）由2.70g／L降至0.2g／L。经XRD分析，无铝存在时脱硅产物为1.5CaO·SiO2·xH2O，有铝存在时脱硅铝产物为Ca2.93Al1.97Si0.64O2.56（OH）9.44