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991.
992.
993.
Francesca Bellezza Antonio Cipiciani Umberto Costantino Fabio Marmottini Maria Anna Quotadamo 《Colloid and polymer science》2006,285(1):19-25
Non-ionic water-in-oil (w/o) microemulsions of pentaoxyethylenenonylphenyl ether (Igepal-CO520)/cyclohexane/water at 25 °C have been used as reaction vessels to obtain zirconium hydrogen phosphate nanoparticles. 相似文献
994.
Franca Scintu Camilla Reali Rita Pillai Manuela Badiali Adele Maria Sanna Francesca Argiolu Maria Serafina Ristaldi Valeria Sogos 《BMC neuroscience》2006,7(1):14-12
Background
It has recently been demonstrated that the fate of adult cells is not restricted to their tissues of origin. In particular, it has been shown that bone marrow stem cells can give rise to cells of different tissues, including neural cells, hepatocytes and myocytes, expanding their differentiation potential. 相似文献995.
The aim of this paper is to discuss the main ideas of the Talagrand proof of the Parisi Ansatz for the free-energy of Mean
Field Spin Glasses with a physicist's approach. We consider the case of the spherical p-spin model, which has the following advantages: (1) the Parisi Ansatz takes the simple “one step replica symmetry breaking
form,” (2) the replica free-energy as a function of the order parameters is simple enough to allow for numerical maximization
with arbitrary precision. We present the essential ideas of the proof, we stress its connections with the theory of effective
potentials for glassy systems, and we reduce the technically more difficult part of the Talagrand's analysis to an explicit
evaluation of the solution of a variational problem. 相似文献
996.
Francesca Benevelli Yaroslav Z. Khimyak Jacek Klinowski 《Journal of inclusion phenomena and macrocyclic chemistry》2004,49(3-4):211-218
Solid-state NMR techniques are used to study the effect of theinclusion of toluene and benzene on the mobility ofp-tert-butylcalixarene. We attribute the great increase inhost mobility upon complexation to the lack of strongdirectional intermolecular interactions. The differences inthe behaviour of the host in the two complexes are explainedin terms of the steric effects of the guest methyl group. 相似文献
997.
Valentina Siracusa Massimo Gazzano Lara Finelli Nadia Lotti Andrea Munari 《Journal of Polymer Science.Polymer Physics》2006,44(11):1562-1571
Poly(diethylene terephthalate‐co‐thiodiethylene terephthalate) (PDET/TDET) copolymers of various compositions were synthesized and characterized in terms of chemical structure and molecular weight. The thermal behavior was examined by thermogravimetric analysis and differential scanning calorimetry. All the polymers showed a good thermal stability. At room temperature they appeared as semicrystalline materials: the main effect of copolymerization was a lowering in the amount of crystallinity and a decrease of melting temperature with respect to homopolymers. WAXD measurements indicated that cocrystallization occurs over an extended composition range and three different crystalline phases have been identified. In particular, the applicability of Wendling–Suter's equation has been checked for the PDET/TDET copolymers with TDET unit content ranging from 60 to 90 mol %. Amorphous samples were obtained after melt quenching and a decrease of Tg as the content of TDET units is increased was observed. This behavior was explained as due to the presence of flexible C? S? C bonds in the polymeric chain. Lastly, the Fox equation well described Tg‐composition data. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1562–1571, 2006 相似文献
998.
Francesca Spadavecchia Michele Ceotto Leonardo Lo Presti Chiara Aieta Iolanda Biraghi Daniela Meroni Silvia Ardizzone Giuseppe Cappelletti 《中国化学》2014,32(12):1195-1213
A state‐of‐the‐art overview of N‐dopant characterizations in nano‐TiO2 second‐generation photocatalysts is provided. The related literature is very rich and sometimes offers contrasting interpretations. Here we critically discuss up‐to‐date literature results and our own findings, as retrieved by several experimental (BET, HR‐TEM, XPS, DRS, HR‐XRPD, EXAFS, electrochemical tools) and theoretical (periodic DFT) techniques. Our intent is to pull together outcomes from very different and complementary sources to make an as much as possible coherent picture of the morphological, electrochemical and electronic properties of N‐TiO2 materials. It is commonly accepted that critical issues to be considered in the design of high‐performing N‐TiO2 photocatalysts are synthetic strategy, defect concentration and chemical nature of the lattice point defects. We focus on the latter two issues, with emphasis on sol‐gel prepared materials, according to the specific area of expertise of our group. The problem of the chemical nature of guest N species into the lattice is crucial, as substitutional (Ns) or interstitial (Ni) nitrogen place their valence states just above the valence band or deeper into the band gap. Overall, we show how synergism among experimental and theoretical techniques is decisive to disentangle structural, electronic and morphological effects in complex N‐doped TiO2 matrices. 相似文献
999.
The paper presents an optimization framework for dealing with morphing airfoils for helicopter rotor blades. With regard to the morphing strategy, a conformable camber line is considered to deal with variable flow conditions encountered in forward flight with the objective of increasing the aerodynamic performance on the advancing and retreating sides of the rotor. Another peculiarity of the method is that the optimal shape is sought to be minimally sensitive to uncertainty in the operating conditions. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
Loretta Laureana del Mercato Marzia Maria Ferraro Francesca Baldassarre Serena Mancarella Valentina Greco Ross Rinaldi Stefano Leporatti 《Advances in colloid and interface science》2014
Polyelectrolyte multilayer (PEM) capsules engineered with active elements for targeting, labeling, sensing and delivery hold great promise for the controlled delivery of drugs and the development of new sensing platforms. PEM capsules composed of biodegradable polyelectrolytes are fabricated for intracellular delivery of encapsulated cargo (for example peptides, enzymes, DNA, and drugs) through gradual biodegradation of the shell components. PEM capsules with shells responsive to environmental or physical stimuli are exploited to control drug release. In the presence of appropriate triggers (e.g., pH variation or light irradiation) the pores of the multilayer shell are unlocked, leading to the controlled release of encapsulated cargos. By loading sensing elements in the capsules interior, PEM capsules sensitive to biological analytes, such as ions and metabolites, are assembled and used to detect analyte concentration changes in the surrounding environment. This Review aims to evaluate the current state of PEM capsules for drug delivery and sensing applications. 相似文献