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Silicone surfactants display unique properties and are widely employed in pharmaceutical and cosmetic products. In this work, we study water incorporation into silicone oils using silicone surfactants. Despite their importance, there are only a few studies reporting their phase equilibrium and structural characterization. Here, we determined the phase diagram of systems containing silicone oils, silicone surfactants, and water. In particular, we investigated the self-assembly behavior of two siloxane surfactants with the different hydrophilic–lipophilic balance: M­(D′E7OH)­M and MD18(D′3E18OAc)­M and two silicone oils (cyclic oilD4 and linear oilMD15M). The phase behavior of the mixtures was investigated through optical inspection and structural characterization of aggregated states (microemulsions and mesophases) using small angle X-ray scattering (SAXS). These water-in-oil microemulsions or bicontinuous microemulsions incorporated a maximum amount of approximately 20 wt % water for the two surfactants with cyclic oil. A similar behavior was also identified with linear silicone oil, though with smaller water contents. We also observed the formation of anisotropic states, with a predominance of lamellar phases and a small region of a hexagonal phase. A quantitative analysis of the SAXS curves in the lamellar region reveals that this mesophase swells continuously after the addition of water lamellar periods ranging from 50 Å (with 18 wt % water) to 64 Å (with 40 wt % water). Our results confirm and expand the earlier literature on similar compounds, indicating their potential in incorporating water into silicone mixtures and forming interesting mesophases. Accompanying this characterization, we also report a comprehensive and systematic set of structural details for the different systems (microemulsions, bicontinuous phases and mesophases) formed by these mixtures, derived from the SAXS measurements.

O bivalve estuarino Iphigenia brasiliensis (Lamarck, 1818) é um recurso de mariscagem amplamente explorado nas regiões Norte e Nordeste do Brasil. Embora a espécie apresente relevância socioeconômica para muitas populações tradicionais, poucas informações a seu respeito estão disponíveis na literatura. Este trabalho teve como objetivo recuperar estudos nos quais I. brasiliensis fosse espécie modelo ou um dado direto da pesquisa. Para tanto, foi realizada uma revisão da literatura utilizando-se de quatro bases de dados digitais. Foram recuperadas 132 publicações, as quais foram caracterizadas por uma análise de conteúdo, bem como tiveram seus dados compilados para uma descrição estatística. Das publicações recuperadas, apenas 17 corresponderam a pesquisas diretamente relacionadas à espécie, ou seja, aquelas em que I. brasiliensis foi o objeto de estudo. A maior parte dos trabalhos levantados nesta revisão referiu-se a espécie, principalmente, como uma das capturas incidentais mais abundantes durante a catação de bivalves comercialmente mais rentáveis. Palavras-chave: Bivalve Estuarino. Catação de Moluscos. Captura Incidental. AbstractIphigenia brasliensis (Lamarck, 1818) is an estuarine bivalve used as commercial and subsistence resource by the traditional communities from North and Northeast of Brazil. Although its socioeconomic relevance, the species is poorly studied and information on it is very rare in the academic literature. The main aim of this review was to recover all available information on I. brasiliensis that was scattered among many different sources. For doing that a search was carried out using four digital databases. 132 publications were recovered and characterized by a content analysis, as well as had their data compiled for a statistical description. Of the recovered publications, only 17 corresponded to research directly related to the species, that is, to those in which I. brasiliensis was the object of study. Most of the literature recovered in this review referred to the species only as one of the most abundant bycatch during the exploitation of other commercially profitable bivalves. Keywords: Estuarine Bivalve. Mollusk Gathering. Bycatch.