Devir-câmera: A relação dos estudantes com os equipamentos de produção de imagens em movimento

Esta pesquisa tem como objetivo cartografar o devir câmera de um grupo de produção audiovisual para verificar de que forma as novas tecnologias de captura produzem uma transformação na relação com as imagens que poderá ser considerada como produção de uma nova subjetividade. Encaramos como devir câmera o resultado do acoplamento estudante/ câmera de vídeo em suas várias manifestações tecnológicas (handycams, câmeras de fotografia digitais, telefones celulares). Como nosso objeto de pesquisa é formado por alunos de ensino médio-técnico e de graduação, também pretendemos apontar possibilidades para a utilização do audiovisual na educação atuando na construção de novos territórios existenciais, no sentido de gerar processos de singularização através da educação pela arte. Nosso campo conceitual tomará consistência através do uso de autores como Gilles Deleuze, Felix Guattari, Michel Foucault; Kastrup, Escóssia, Benevides, Passos, Suely Rolnik; Michael Hardt, Toni Negri, Peter Pal Pelbart, Gilbert Simondon, McLuhan, Pierre Lévy; Jonathan Crary, Pierre Barboza, e Phillipe Dubois, além da bibliografia técnica/tecnológica da área.

Hierarchical electrohydrodynamic structures for surface-enhanced Raman scattering.

Surface enhanced Raman scattering (SERS) is a well-established spectroscopic technique that requires nanoscale metal structures to achieve high signal sensitivity. While most SERS substrates are manufactured by conventional lithographic methods, the development of a cost-effective approach to create nanostructured surfaces is a much sought-after goal in the SERS community. Here, a method is established to create controlled, self-organized, hierarchical nanostructures using electrohydrodynamic (HEHD) instabilities. The created structures are readily fine-tuned, which is an important requirement for optimizing SERS to obtain the highest enhancements. HEHD pattern formation enables the fabrication of multiscale 3D structured arrays as SERS-active platforms. Importantly, each of the HEHD-patterned individual structural units yield a considerable SERS enhancement. This enables each single unit to function as an isolated sensor. Each of the formed structures can be effectively tuned and tailored to provide high SERS enhancement, while arising from different HEHD morphologies. The HEHD fabrication of sub-micrometer architectures is straightforward and robust, providing an elegant route for high-throughput biological and chemical sensing.

Hierarchical electrohydrodynamic structures for surface-enhanced Raman scattering (adv. Mater. 23/2012).

On page OP 175, U. Steiner and co-workers destabilise polymer trilayer films using an electric field to generate separated micrometre-sized core-shell pillars, which are further modified by selective polymer dissolution to yield polymer core columns surrounded by a rim and micro-volcano rim structures. When coated with gold and decorated with Raman active probes, all three structure types give rise to substantial enhancement in surface-enhanced Raman scattering (SERS). Since this SERS enhancement arises from each of the isolated structures in the array, these surface patterns are an ideal platform for multiplexed SERS detection.

Optimized vertical carbon nanotube forests for multiplex surface-enhanced raman scattering detection

The highly sensitive and molecule-specific technique of surface-enhanced Raman spectroscopy (SERS) generates high signal enhancements via localized optical fields on nanoscale metallic materials, which can be tuned by manipulation of the surface roughness and architecture on the submicrometer level. We investigate gold-functionalized vertically aligned carbon nanotube forests (VACNTs) as low-cost straightforward SERS nanoplatforms. We find that their SERS enhancements depend on their diameter and density, which are systematically optimized for their performance. Modeling of the VACNT-based SERS substrates confirms consistent dependence on structural parameters as observed experimentally. The created nanostructures span over large substrate areas, are readily configurable, and yield uniform and reproducible SERS enhancement factors. Further fabricated micropatterned VACNTs platforms are shown to deliver multiplexed SERS detection. The unique properties of CNTs, which can be synergistically utilized in VACNT-based substrates and patterned arrays, can thus provide new generation platforms for SERS detection. © 2012 American Chemical Society.

金纳米粒子的组装和超晶格结构

本论文采用分子组装技术（包括LB技术和自组装技术）制备了金纳米粒子与有机物复合的超晶格结构，同时系统地研究了有机物组份和纳米粒子尺寸和形态对超晶格量子化特性的调整。首次采用自组装技术和LB技术结合的手段制备了十八硫醇、十八胺及其混合成分与金纳米粒子复合的超晶格结构。研究表明在这种超晶格结构中，金纳米粒子和有机分子之间的相互作用改变了电子跃迁所需的能量，使得电子的跃迁呈现出强烈的量子化特性，电子跃迁能随着十八胺含量的增大而逐渐降低。十二烷基硫醇（DDT）包裹的金纳米粒子可以通过浇铸膜方法自发得到二维地超晶格结构。而我们采用LB沉积技术制备了粒子的单层膜和多层膜，对结构的研究证实在单层膜的二维方向以及多层膜的三维方向，金纳米粒子由相互交叉的DDT连接。表明通过LB方法制备了金纳米粒子和DDT复合的二维和三维超晶格结构。利用自组装方法制备了由1，6－已烷双硫醇连接的金纳米粒子自组装多层膜。研究确认在这种组装多层膜中粒子尺寸小和包裹金纳米粒子的3－巯基丙酸的耦合作用是增强膜中粒子之间偶合作用的两个主要因素，粒子之间的偶合作用越大，电子跃迁所需的能量降低。而对于超晶结构，小粒子好于大粒子，包裹的粒子优于未包裹的。对金纳米粒子自组装单层膜这种新兴的SERS活性基底进行了初步研究，首次得到了以此为基底的酞菁铜LB单层膜的SERS谱。

聚苯胺、聚苯胺纳米复合材料的光谱电化学研究

导电聚合物在防腐、传感和二次电池等方面具有很高的应用价值。表面增强拉曼光谱（SERS）对界面信息有较高的灵敏度和选择性，特别是原位技术可以提供详细的界面信息。我们确定了用本实验室己经很成熟的自组装膜技术对电极进行功能化修饰，再结合原位电化学SERS方法对聚苯胺的电化学初聚过程进行研究，进一步了解了聚合成膜的机理；为有目的地构造具有特殊结构和用途的聚苯胺以及聚苯胺与纳米粒子的复合功能材料提供理论依据。1．在4-ATP／金修饰电极上化学接枝制备4一琉基偶氮氨基苯单层膜；我们首先在经电化学氧化还原粗糙化处理的金电极上组装了4-ATP分子并且得到了具有较高信噪比的拉曼增强信号；继而我们又利用经典的重氮化偶联反应接枝了苯胺分子得到了稳定的具有较高电化学活性的对琉基偶氮苯单层膜。2．在4-ATP／金修饰电极上进行了苯胺电化学聚合过程的原位SERS研究；通过采用原位电化学循环伏安一表面增强拉曼光谱法，研究了在硫酸介质下苯胺在4-ATP修饰的金电极上的起始聚合情况，并与未经修饰的裸金电极进行了对比，认为：具有高度电子导电性的4-ATP分子对苯胺的聚和起到了促进作用；得到的聚苯胺薄膜继承了4-ATP分子自组装膜的有序结构，采取的是苯胺的C_4位与下层的4-ATP分子的N位进行头一尾偶联聚和。3．聚苯胺与金属和非金属纳米复合材料的制备；全部采用电化学聚合的方法，制备了聚苯胺／金纳米粒子，聚苯胺／碳纳米管，聚苯胺／碳纳米管／金纳米粒子／的复合膜。通过形貌和电化学表征，认为金纳米粒子和碳纳米管在聚苯胺膜中分布均匀，形成了比较好的复合材料，且具有良好的导电性能，有望在二次电池和传感器方面有较好的应用。

纳米结构的构建与表征

在纳米尺寸上按照人们意愿排列物质分子、原子以及进行材料和分子的剪裁具有重 要的研究意义。本论文利用扫描探针加工技术构建种类、形状、尺寸等可控的纳米结构，并且结合表面增强拉曼光谱，对其进行了表征。同时，发展了一种合成可控形貌半导纳米结构的溶液方法，观察了在溶剂挥发作用下纳米粒子在固一液界面的白组装，这种白组装现象有望实现自然自聚集纳米器件的合成。并且制备了一种高效拉曼活性基底，稳定性和重复性好。1．探针针尖性能对扫描探针刻蚀（SPL）的影响采用四种不同类型的针尖：标准Si3N4针尖、敲击模式刻蚀Si针尖、俄罗斯针尖（末覆涂层的Si针尖）、导电针尖进行扫描探针刻蚀实验。发现针尖性能是刻蚀过程中一个重要的因素。具有较小弹性常数的针尖不易在基底进行图案刻划和粒子的操纵。并且，给出了才目应的机理。2．利用“纳米笔”加工技术（DPN）直接构建纳米结构 罗丹明6G（R6G）是一种重要的激光染料和生物染料。利用“纳米笔”加工技术在新解 离的云母表面获得了R6G分子排列。R6G分子通过静电作用结合在云母表面，并且形 成稳定的R6G纳米结构。通过控制针尖不同的运动方向，在云母上构建了不同形状的R6G纳米结构。同时讨论了针尖运行速度和接触时间对DPN的影响。结合表面增强拉曼散射效应，对这些构建的纳米结构进行了定性验证。聚-L-赖氨酸是一种常用的表面修饰试剂，它可以增强生物分子或细胞与表面间的吸附力。利用OPN技术成功的在云母表面获得了聚-L-赖氨酸纳米结构。通过控制针尖不同的运动方向，在表面构建了不同形状包括方块、线条、点、十字花等纳米图案。这种局 部或特定区域的修饰表面在生物化学传感器或微、纳米排列的实现上具有重要的潜在应用价值。牛血．清白蛋白和小牛胸腺组蛋白都是非常重要的蛋白质分子。利用DPN技术将这些蛋自质分子成功的沉积在云母表面。同时考察了针尖一基底接触时间及针尖运行速度对OPN 的影响。这种蛋白质纳米结构的构建为生物纳米器件的最终实现提供了一条简单而有效的途径。3．ZnO纳米结构可控合成及其在固一液界面的自组装使用一种简单而温和的方法直接在溶液中合成了不同ZnO纳米结构。通过调节水一甲醇比率，分别获得zno纳米线、纳米棒和纳米粒子。获得的这些ZnO纳米结构用AFM、XPS及荧光光谱加以表征。讨论了水一甲醇比率对合成ZnO纳米结构不同形貌的影响，给出了可能的机理。溶剂挥发作用卜，zno纳米粒子在云母和玻璃表面进行白组装。不同条件卜，获得不同形状的自组装排列图案。结合现有理论，给出了合理解释。这种方法可以引导纳米粒子的排列，有望实现白然自聚集纳米器件的合成。4．表面增强拉曼活性基底制备和表征使用CTAB，利用一种简单的方法制备了SERS活性基底，并且呈现很好的拉曼响应。对于R6G的检测浓度可以达到1*10-14M，且稳定性和重复性好。结合重定位技术，获得了银纳米晶、簇和膜的AFM图像，而且获得了单分子R6G在同一聚集位置上的SERS光谱。讨论了增强因子的影响因素，并且给出了合理的机理。

苯胺电吸附聚合及聚苯胺拉曼光谱研究

本工作包括两个方面。其一，利用SERS技术研究苯胺在电极上的电吸附和聚合过程；其二，利用共振拉曼光谱技术研究聚苯胺本征态结构。掺杂机理和化学反应机制。通过改变体系为PH值、单体浓度、电极电位和激发光功率，我们得到苯胺的SER谱，埃谱与液态苯胺的拉曼光谱十分相象。实验中还发现单体苯胺SER谱的获得条件十分苛刻，与单体的纯度、PH值、入射光功率，电极电位都密切相关。拉曼光谱用于聚苯爱的研究，本工作主要包括三个方面。1、利用共振性拉曼效应、不同条件下光谱的变化。模型化合物的指认及和外光谱的结果，并参考文献上的数据，对聚苯胺本征态拉曼光谱作了详细归属，同时了解到聚苯胺分子中除了少量的-N=N-。氯代，1、2取代结构外，主要是由苯胺和醌二亚胺组成的线性结构。其中苯环和醌环的含量比是3比1。2、根据掺垛过程中聚苯胺拉曼光谱的变化，特别是红光和紫光激发时掺杂态聚苯胺拉曼光谱的区别，我们提出了四单元苯醌变体的掺杂模型。3、通过电化学现场拉曼光谱跟踪研究，确认0.5M MC104体系中，330mV电化学现场聚苯胺相当于本征态样品的HCl化学掺杂态，750mV附近掺杂态取苯胺进一步电化学氧化，每四个环放击4个H~1和两个电子变成醌二亚胺结构；在200mV附近，聚苯胺由完全还原态经电化学氧化每四个环失去三个电子变成掺杂态，这一反应可被分解为两个连续的单电子过程。实验中还发现样品中醌环的含量过多或过少都影响掺杂反应的发生，当醌环与苯环之比为1比3时，样品极易被掺杂，此时样品的掺杂电异率也最高。

Surface-enhanced Raman scattering from surfactant-free 3D gold nanowire networks substrates

A useful method for the fabrication of three-dimensional gold nanowire networks based on the chemical reduction of HAuCl4 with trisodium citrate was presented. The coverage of the 3D gold nanowire networks was tunable by altering precursor concentration. The as-prepared 3D gold nanowire networks could be used as surface-enhanced Raman scattering (SERS) substrates and examined by 4-aminothiophenol (4-ATP) as a probe molecules.

Adsorption of 4,4 '-thiobisbenzenethiol on silver surfaces: surface-enhanced Raman scattering study

Adsorption of 4,4'-thiobisbenzenethiol (4,4'-TBBT) on a colloidal silver surface and a roughened silver electrode surface was investigated by means of surface-enhanced Raman scattering (SERS) for the first time, which indicates that 4,4'-TBBT is chemisorbed on the colloidal silver surface as dithiolates by losing two H-atoms of the S-H bond, while as monothiolates on the roughened silver electrode. The different orientations of the molecules on both silver surfaces indicate the different adsorption behaviors of 4,4'-TBBT in the two systems.

Facile fabrication of gold nanoparticle arrays for efficient surface-enhanced Raman scattering

An effective and facile method for the fabrication of a surface-enhanced Raman scattering (SERS)-active film with closely packed gold nanoparticle (AuNP) arrays is proposed by self-assembly of different sizes ( 16, 25, 40 and 70 nm) of AuNPs at a toluene/water interface with ethanol as the inducer. The as-prepared AuNP arrays exhibit efficient Raman scattering enhancement, and the enhancement factors estimated using p-aminothiophenol as a probe molecule range from 10(5) to 10(7).

Facile fabrication of large area of aggregated gold nanorods film for efficient surface-enhanced Raman scattering

An effective and facile method for fabrication of large area of aggregated gold nanorods (AuNRs) film was proposed by self-assembly of AuNRs at a toluene/water interface for the first time. It was found that large area of aggregated AuNRs film could be formed at the interface of toluene and water due to the interfacial tension between the two phases. The obtained large area of aggregated AuNRs film exhibits strong surface-enhanced Raman scattering (SERS) activity with 4-aminothiophenol (4-ATP) and 2-aminothiophenol (2-ATP) as the probe molecules based on the strong electromagnetic coupling effect between the very adjacent AuNRs.

Large-area silver-coated silicon nanowire arrays for molecular sensing using surface-enhanced Raman spectroscopy

A new and facile method to prepare large-area silver-coated silicon nanowire arrays for surface-enhanced Raman spectroscopy (SERS)-based sensing is introduced. High-quality silicon nanowire arrays are prepared by a chemical etching method and used as a template for the generation of SERS-active silver-coated silicon nanowire arrays. The morphologies of the silicon nanowire arrays and the type of silver-plating solution are two key factors determining the magnitude of SERS signal enhancement and the sensitivity of detection; they are investigated in detail for the purpose of optimization.

Environmentally friendly synthesis of highly monodisperse biocompatible gold nanoparticles with urchin-like shape

We report a facile and environmentally friendly strategy for high-yield synthesis of highly monodisperse gold nanoparticles with urchin-like shape. A simple protein, gelatin, was first used for the control over shape and orientation of the gold nanoparticles. These nanoparticles, ready to use for biological systems, are promising in the optical imaging-based disease diagnostics and therapy because of their tunable surface plasmon resonance (SPR) and excellent surface-enhanced Raman scattering (SERS) activity.

Microarray based Raman spectroscopic detection with gold nanoparticle probes

microarray approach based on surface-enhanced Raman spectroscopic (SERS) was developed for detection of spotted peptide, peptide-protein or protein-antibody interaction. The procedure involves the attachment of peptide-capped gold nanoparticles followed by silver deposition for signal enhancement. The attachment of the gold nanoparticles is achieved by standard avidin-biotin chemistry. The well-known biomolecular recognition pairs, IgG/protein A and biotin/avidin, were used to demonstrate proof-of-concept of the SERS assay.