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Helical rosette nanotubes are obtained through the self-assembly of low molecular weight synthetic modules in water. Here we demonstrate that despite their dynamic nature, these materials respond very well to directional fluid flow and assume long-range order on flat substrates. Persistence length, order, and packing of the rosette nanotubes were found to depend dramatically on the surface properties of both the substrate and the nanotubes and vary from well-ordered long-range 2D films to bundled nanotubes or amorphous conglomerates. While flow-induced long-range alignment of dynamic nanostructures is unprecedented, the chemical tunability of the rosette nanotubes is anticipated to offer a versatile means for investigating the basis of interfacial forces in self-assembled organo-silicon devices and their effect on the stability and physical properties of organic nanostructures on electroactive surfaces. 相似文献
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Fabio Mazzotti Leonardo Di Donna Hicham Benabdelkamel Bartolo Gabriele Anna Napoli Giovanni Sindona 《Journal of mass spectrometry : JMS》2010,45(4):358-363
Pterostilbene (trans‐3,5‐dimethoxy‐4‐hydroxystilbene) is an active component found in several plant species, exhibiting important pharmacological properties. A new and reliable method of assaying this phyto compound in various matrices is presented; the assay is based on (1) the selectivity of liquid chromatography (LC) hyphenated with electrospray ionisation (ESI), (2) the specificity of a two‐step mass spectrometric analysis (MS/MS) and (3) the accuracy of the isotope dilution method. The labelled analogue may be conveniently synthesised in a few steps. The sensitivity of the method is confirmed by the very low limit of detection (LOD) and limit of quantitation (LOQ) values achieved in the assay of pterostilbene in two distinct fortified matrices, and is further supported by the observed accuracy values. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Ali Deeb Mahmoud Kotb Mohamed El-Abbasy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2245-2252
3-Substituted pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-2,4-di-ones and 3-amino-2-methylpyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine-4-ones were synthesized starting from ethyl 5-aminothieno[2,3-c] pyridazine-6-carboxylate 1. Reaction of amino ester 1with phenyl isothiocyanate affords thiourea derivative 10which undergo further transformation to the related fused heterocyclic systems. 相似文献
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Hadid Maria Noukrati Hassan Ben youcef Hicham Barroug Allal Sehaqui Houssine 《Cellulose (London, England)》2021,28(12):7893-7908
Cellulose - Enhancing the sorption properties of cellulose is a prerequisite for its efficient use in water purification as an alternative to costly activated carbon. Here, solvent-free... 相似文献