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Silver halide sensitized gelatin (SHSG) is an interesting technique for the production of holographic optical elements. It combines the high sensitivity of photographic emulsions with the well-known low scattering and high diffraction efficiency corresponding to dichromated gelatin. In this paper…

Obtaining holographic volume gratings with high diffraction efficiencies that can be used under white light has been a serious problem for the polyvinyl alcohol-acrylamide-based photopolymers developed by other researchers. In this paper we propose to eliminate the residual monomer in…

Purpose: To evaluate and compare visual, refractive, and corneal aberrometric outcomes after implantation of 2 types of intrastromal corneal ring segments (ICRS) in eyes with early to moderate ectatic disease. Settings: Vissum Corporation-Instituto Oftalmológico de Alicante, Alicante, Spain. Methods: This…

Ce mémoire de maitrise porte sur la représentation de l’ailleurs véhiculée aux lecteurs d’images, au Québec, par les gravures du journal illustré L’Opinion publique. Effectivement, si l’Histoire commence avec les premières traces écrites, elle pose le problème de l’étude historique…

O emprego de coberturas comestíveis na conservação de frutas na condição pós-colheita, sejam intactas ou minimamente processadas, temsido preconizado como uma tecnologia emergente e de grande potencial, principalmente para aplicações sobre frutas de origem tropical. Diversos biopolímeros têm sido avaliados…

3,3'-Bis(dialkylaminomethyl)-1,1'-binaphth-2-ols (Binolams) have emerged during the last five years as very efficient chiral ligands in many enantioselective processes. Enantiomerically pure Binolams are easily accessible by means of a variety of methods, the most widely used being the so-called chiral Binol…

A new aqueous photopolymer containing the monomers acrylamide, N,N'-methylenbisacrylamide and zinc acrylate, the initiators 4,5-diiodosuccinylfluorescein (2ISF) and methylene blue (MB), and the coinitiator sodium p-toluenesulphinate is described. This formulation exhibits a clear enhancement of the high-energy sensitivity upon irradiation with…

O uso de mistura de agroquímicos constitui prática relativamente comum na agricultura. A saúde humana pode ser afetada pelos agrotóxicos diretamente ou através do contato com produtos e/ou ambientes por estes contaminados ? e, indiretamente, através da contaminação da biota…