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111.
Monique G.A. da Silva Ábner M. Nunes Simoni M.P. Meneghetti Mario R. Meneghetti 《Comptes Rendus Chimie》2013,16(7):640-650
Gold nanorods (AuNRs) were obtained via a wet chemistry technique, in aqueous medium, employing crystallisation seeds. The kinetics of formation, the aspect ratio, and the selectivity of the particles were evaluated according to the parameters of synthesis: the growth-driving agent, seed, and gold precursor concentrations. In 2–4 h, the rod particles attained the expected size and shape under kinetic control, and were stable for at least 2 days. In order to obtain good quality AuNRs in good yields, without enrichment, we suggest keeping the growth-driving agent/gold molar ratio, the AuI/seed ratio, and the concentration of the reagents in the final solution within specific ranges. For example, even if good molar ratios between the reagents are maintained, relatively highly concentrated reaction solutions lead to AuNRs with lower aspect ratios. The main properties of the prepared colloidal systems and the nanoparticles were evaluated by UV–vis spectroscopy and transmission electron microscopy, respectively. 相似文献
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Villagomez-Guzman Ana K. Rodriguez-Garcia Gabriela del Rio Rosa E. Oliveros Ortiz Antonio J. Cerda-Garcia-Rojas Carlos M. Joseph-Nathan Pedro Gomez-Hurtado Mario A. 《Chemistry of Natural Compounds》2021,57(2):319-322
Chemistry of Natural Compounds - A known kaurenoic acid (1), together with a new kaurane derivative named 3α-isobutyryloxykaurenoic acid (2), was isolated from the roots of Lasianthaea aurea,... 相似文献
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Mario Lamberger Florian Mendel Vincent Rijmen Koen Simoens 《Designs, Codes and Cryptography》2012,62(1):1-18
We investigate generic methods to find near-collisions in cryptographic hash functions. We introduce a new generic approach
based on methods to find cycles in the space of codewords of a code with low covering radius. We give an analysis of our approach
and demonstrate it on the SHA-3 candidate TIB3. 相似文献
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Mario Jug Francesca Maestrelli Paola Mura 《Journal of inclusion phenomena and macrocyclic chemistry》2012,74(1-4):87-97
β-Cyclodextrin (βCD) and its soluble polymeric derivative (EPIβCD) were used to improve the effectiveness of chitosan-based bucco-adhesive film formulations containing bupivacaine hydrochloride and triclosan as poorly-soluble model drugs. The film formulations were characterized in terms of swelling, mucoadhesion and in vitro drug release, while possible interactions between the components were investigated by DSC and FTIR analyses. For both drugs EPIβCD showed a higher solubilizing efficiency than βCD; however cyclodextrin effectiveness in improving the release rate from film formulations was influenced by their different interactions with chitosan. Free βCD acted as a channelling agent, favouring the film swelling, while EPIβCD due to interaction with chitosan caused an opposite effect. βCD was the optimal partner for bupivacaine-loaded films in terms of film swelling, mucoadhesion and drug release. Contrariwise, EPIβCD was the best partner for triclosan-loaded films, allowing the highest drug release rate increase, due to its higher solubilizing ability with respect to βCD. Addition of the suitable cyclodextrin enabled formulation of buccal films with suitable drug release properties. 相似文献