Search results for "EMU"
showing 10 items of 2247 documents
Entrapment of Phenytoin into Microspheres of Oleaginous Materials: Process Development and in Vitro Evaluation of Drug Release
1997
AbstractA novel multiparticulate preparation of the antiepileptic agent phenytoin (1) was developed and evaluated in vitro. The preparation consists of gastroresistant microparticulate drug delivery system formulated with oleaginous material (lipospheres) to minimize unwanted effects of l on gastric apparatus. The drug was dispersed in a spherical micromatrix consisting of a mixture of stearyl alcohol and glycerol esters of various fatty acids. The best mixture to obtain discrete, reproducible, free-flowing lipospheres consisted of glyceryl monostearate dilaurate and stearyl alcohol (ratio 3: 17). The lipospheres were obtained by a technique involving melting and dispersion of drug-containi…
Carnauba wax microspheres loaded with valproic acid: Preparation and evaluation of drug release
1995
AbstractTo minimize unwanted toxic effects of valproic acid (1) by the kinetic control of drug release, gastroresistant carnauba wax microspheres loaded with the antiepileptic agent were prepared. The preparation was based on a technique involving melting and dispersion of drug-containing wax in an aqueous medium. The resulting emulsion after cooling under rapid stirring produced solid, discrete, reproducible free flowing microspheres which converted the liquid drug droplets into solid material. About 94% of the isolated microspheres were of particle size range 200-425 μm. The microspheres were analyzed to determine the drug content in various particle size range and to characterize the in …
Small angle neutron scattering studies of critical phenomena in a three-component microemulsion
2007
Critical density fluctuations of a ``water-in-oil`` microemulsion consisting of water, benzene, and BHDC (benzyldimethyl-n-hexadecyl ammonium chloride) were observed near the phase boundary by SANS. Observed profiles were well described by product of a form factor of spherical droplets and a structure factor, consisting of a term describing the inter-droplet correlations and also an Ornstein- Zernike component describing the droplet density fluctuations. Allowance was also made fro droplet polydispersity,though the width of the distribution turned out to be very small (1-2%). Observed temperature dependence of osmotic compressibility was fitted using the crossover function proposed by Belya…
Nanosized shape-changing colloids from liquid crystalline elastomers.
2010
A method to prepare shape-changing nanospheres from liquid crystalline elastomers is reported. The nanosized colloids are prepared by a miniemulsion process. During this process, colloids are prepared from a liquid crystalline (LC) main-chain polyester and subsequently crosslinked into a nanometer-sized LC elastomer. The ability of these LC elastomers to change their shape at the phase transition temperature from the smectic A to the isotropic phase was detected by temperature-dependent transmission electron microscopy. The phase transition-induced shape change leads to strongly shape anisotropic nanosized elastomer particles.
Granting Epicurean Wisdom at Rome: Exchange and Reciprocity in Lucretius' Didactic (DRN 1.921-950)
2018
In the first book of De Rerum Natura, Lucretius describes his didactic undertaking as a metaphorical process of gift exchange (1.50-53): the obscure and salvific precepts of Epicurean philosophy, skilfully arranged in hexameters, are said to be 'gifts' (dona) that the poet has prepared with loyal zeal (studio fideli). Such a suggestive depiction of Lucretius' relationship to the work's dedicatee, Gaius Memmius, seems to reflect a relevant functional pattern of De Rerum Natura as a coherent system of communication strategies, variously readapting social models and cultural traditions. The present paper employs the interpretative approach of gift theories – the thought-provoking theories elab…
Libraries and Intellectual Debate in the Late Republic: the Case of the Aristotelian Corpus
2013
The present chapter explores the catalyzing function of libraries in the intellectual debate of the late Roman Republic, by focusing on the significant case of the Aristotelian esoteric corpus. A careful analysis of the literary and historical evidence concerning the use of Peripatetic texts allows to detect the presence of at least two important libraries containing Aristotle's 'pragmatiai' in Roman Italy: Lucullus' collection in Tusculum and Sulla's one in Cumae. Several Greek and Latin sources bear witness to the vicissitudes of such libraries, and the present paper reassesses their accounts in order to point out the close connection between intellectual patterns and material culture - i…
Filodemo, Cicerone, Nepote: a proposito del contesto storico-culturale di Oec. Col. XXII.9-48
2018
Until recently, Philodemus’ treatise On Household Management (Περὶ οἰκονομίας, PHerc. 1424) has been mainly used as a source for the reconstruction of early Epicurean economic thought (especially of Metrodorus’ writing Περὶ πλούτου). Over the past few years, however, scholars have called attention to Philodemus’ creative (yet philosophically orthodox) readaptation of Epicurean ethical and social theories to the needs of contemporary Roman society. Following this scholarly line, the present paper reassesses a passage from On Household Management (col. XXII.9–48) which has so far been interpreted as an unoriginal repetition of Metrodorus’ arguments, and situates it in the cultural context of …
Microwave-assisted synthesis of anhydrous CdS nanoparticles in a water-oil microemulsion.
2006
Abstract Microwave irradiation at a frequency of 2.45 GHz and a power ranging between 22 and 30 W was used, in a water–oil microemulsion at 35 ± 2 ° C , to obtain stable, small, crystalline, anhydrous CdS nanoparticles exhibiting enhanced luminescence properties. The process of nanoparticles growth at different irradiation times was followed by UV–vis spectroscopy. It was observed that irradiated nanoparticles grew faster and their size reached a constant value. The final mean nanoparticle diameter was 2.7 nm, smaller than that observed in a non-irradiated sample, in which particle dimensions slowly increased even after 10 h. This finding was confirmed by high resolution transmission electr…
Photonic Crystals from Core-Shell Colloids with Incorporated Highly Fluorescent Quantum Dots
2005
We report the preparation of nanoscaled PS/PMMA core-shell spheres with highly fluorescent CdS/ZnS coated CdSe quantum dots (QDs) integrated in the core. Core-shell spheres of different diameters have been self-assembled to colloidal photonic crystals (PCs) with photonic stop bands located in the visible range of the electromagnetic spectrum. For the synthesis of the core, a modified miniemulsion polymerization has been used; the shell was prepared by a newly developed core-shell polymerization. The CdSe QDs embedded in the core were coated with the higher band gap semiconductor materials CdS and ZnS in a successive ion layer adsorption reaction (SILAR) keeping up the light-emitting propert…
Microwave radiation effect on the synthesis of cadmium sulphide nanoparticles in water in oil microemulsion: a preliminary study at different frequen…
2004
AbstractCadmium sulphide nanoparticles have been synthesised in water/sodium bis (2-ethylhexyl) sulfosuccinate (AOT)/n- heptane microemulsions kept at 30 °C by microwave irradiation coupled with water-cooling and in conventional thermostatic conditions at the same temperature. The study has been performed exposing the reaction media to microwave radiation at five different frequencies (2.45, 2.85, 8, 12 and 18 GHz). For each frequency, a suitable microwave exposure set-up has been assembled. During the growth process, the dimensions of the nanoparticles have been characterised by means of UV-Vis spectroscopy. At the end of the growth process, the surface morphology of the nanoparticles has …