A atual pesquisa científica possui características próprias resultantes de um processo histórico longo, demorado e denso. Para se compreender a importância da química dentro da sociedade é preciso levar em consideração os caminhos percorridos historicamente por essa ciência. Considerando que a ciência existe na mente dos cientistas, e que não existe uma maneira pré-determinada para a prática da ciência, torna-se de extrema importância a qualidade na formação do cientista. O químico formado, que tanto pode atuar na indústria quanto na área acadêmica, precisa seguir uma série de condutas éticas e ser um profissional reflexivo. O livro didático se constitui em veículo privilegiado para a comunidade química projetar as visões que considera adequadas para serem assimiladas pelo futuro profissional a respeito da química, as quais podem se diferenciar de acordo com as intenções do autor. Esta dissertação buscou selecionar e analisar alguns livros didáticos de química geral utilizados no ensino universitário de química, a fim de investigar as relações entre química e sociedade apresentadas neles. Os resultados mostram que os livros didáticos analisados atendem, de maneira ampla, ao estudante que se formará um químico para a indústria, mais do que a um químico acadêmico. Em todos os livros didáticos analisados foram encontradas menções a algum problema ambiental, em geral abordados como se fossem um percalço no trabalho dos químicos, algo como um acidente inevitável. Além da ausência de autocrítica a respeito da atuação dos químicos, foi encontrada a valorização do cientista como um transformador social. A abordagem histórica nos livros é feita de maneira superficial, limitando-se a nomes e datas. Os resultados sugerem que os autores de livros didáticos não se propõem a incluir neles conteúdos e atividades que poderiam proporcionar uma formação mais completa e diversificada, no sentido de problematizar o papel da química na sociedade. Uma formação mais crítica poderia colocar melhores profissionais no mercado, mais cientes de seus compromissos éticos, para além do domínio técnico de suas áreas de atuação. / Current scientific research has its own characteristics resulting from a long and dense historical process. To understand the relevance of chemistry in society it is necessary to take into account the historical paths taken by this science. Whereas science exists in the minds of scientists, and that there is no predetermined way to the practice of science, quality becomes extremely important in the formation of scientists. Professional chemists acting either in industry or academia need to follow a series of ethical guidelines and be reflective in their tasks. Textbooks constitute excellent vehicles for the diffusion of issues the chemical community consider appropriate to be assimilated by future professionals concerning chemistry. Such issues may differ according to the author\'s intentions. This research aimed at selecting and analyzing general chemistry textbooks used in university level chemistry courses in order to investigate the relationships between chemistry and society presented in them. Results show that the analyzed textbooks are mainly aimed at students who will work as chemists in industries, more than in universities. In all analyzed textbooks were found mentions on at least one environmental problem, and in general such problems were addressed as a mishap in chemists\' work, or something like an unavoidable accident. Besides the absence of self-criticism about the professional performance of chemists, scientists are presented as the agents of benign social changes. The historical approach in the textbooks is superficially done, usually consisting of a mere mention of names and dates. The results suggest that textbook authors do not consider the inclusion of contents and activities that could provide a more complete and diverse education by discussing the role of chemistry in society. A more critical training could put better professionals in the market: chemists more aware of their ethical commitments, beyond the technical mastery of their area of expertise.

The growth of Co (0001) films and Cr2O3 (0001)/Co (0001) has been investigated using surface analysis methods. Such films are of potential importance for a variety of spintronics applications. Co films were directly deposited on commercial Al2O3 (0001) substrates by magnetron sputter deposition or by molecular beam epitaxy (MBE), with thicknesses of ~1000Å or 30Å, respectively. Low Energy Electron Diffraction (LEED) shows hexagonal (1x1) pattern for expected epitaxial films grown at 800 K to ensure the hexagonally close-packed structure. X-ray photoemission spectroscopy (XPS) indicates the metallic cobalt binding energy for Co (2p3/2) peak, which is at 778.1eV. Atomic force microscopy (AFM) indicates the root mean square (rms) roughness of Co films has been dramatically reduced from 10 nm to 0.6 nm by optimization of experiment parameters, especially Ar pressure during plasma deposition. Ultrathin Cr2O3 films (10 to 25 Å) have been successfully fabricated on 1000Å Co (0001) films by MBE. LEED data indicate Cr2O3 has C6v symmetry and bifurcated spots from Co to Cr2O3 with Cr2O3 thickness less than 6 Å. XPS indicates the binding energy of Cr 2p(3/2) is at 576.6eV which is metallic oxide peak. XPS also shows the growth of Cr2O3 on Co (0001) form a thin Cobalt oxide interface, which is stable after exposure to ambient and 1000K UHV anneal.

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This work was primarily devoted towards a high energy shock wave and its effect upon a completely harmonic system. A classical linear model of twenty diatoms was formulated and perturbed via a ballistic particle of equivalent mass. The inner two diatom pairs were chosen for the classical study in order to restrict center of mass movement within the lattice and to represent inner lattice substituents. These inner atoms were perturbed by direct interactions of their neighbor atoms (entering and absorbing driving atoms). Wyatt and Marston used the action of these atoms to establish a time-dependent driving potential for two diatoms. The entering atom (q) provided the initial interaction from the shock to the cluster; whereas, the absorbing atom (q) acted as a reservoir for the energy to be released from the cluster. The dynamical data from the classical results of q and q was used directly to formulate an interaction potential for a quantum mechanical model of two diatoms; thus, the classical and quantum model experienced similar potentials. The quantum model was represented by four normal modes, upon perturbation yielded quantum dynamical data for comparison to the classical system. Wyatt and Marston showed that a high energy shock imposed upon a harmonic quantum system converges, as expected, to the classical results. (MJM)

CIVINS / Groundwater contamination due to leaky underground fuel tanks is a common problem at civilian and military sites worldwide. The U.S. EPA estimates that 35% of the U.S.'s underground motor fuel tanks are leaking (1 ), which corresponds to approximately 2 million tanks, and approximately 40% have resulted in groundwater contamination (2). Benzene, toluene, ethylbenzene, and xylenes (known collectively as BTEX) are water-soluble fuel constituents that comprise 50 wt % of the water-soluble fraction of gasoline (3). The occurrence of BTEX in groundwater is of concern due to the hazards that they pose toward human health. For example, benzene is a confirmed carcinogen and toluene, while it is less toxic than benzene, depresses the central nervous system. The EPA water quality criterion for benzene and toluene in drinking water is 0.005 mg/Land 14.3 mg/L, respectively (4).