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101.
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Microfocus X‐ray scattering and micro Raman spectroscopy have been applied to study the β‐transcrystalline morphology in isotactic polypropylene. The transformation from the α‐ to the β‐form through the so‐called bifurcation of growth mechanism has been investigated with high spatial resolution. We found that the mixed α–β region does not present spatial correlation along the shearing direction, implying that there is no cooperative crystallization from the different β‐nucleation centres. In addition, a strong change in the lamellar orientation of the α‐form thin layer that induces the growth of the β‐crystallites has been observed for the first time. Finally, changes in the relative intensities of some selected Raman bands allowed the observation of the α–β transformation process at the molecular level.
103.
Pedro López García Fabio Pereira Gomes Maria Inês Rocha Miritello Santoro Érika Rosa Maria Kedor-Hackmann Jose Luis Vilchez Quero Alberto Navalón Montón Guillermo Crovetto Montoya Mercedes Aguilera Cabrera 《Chromatographia》2011,73(7-8):799-805
Vecuronium bromide is a neuromuscular blocking agent used for anesthesia to induce skeletal muscle relaxation. HPLC and CZE analytical methods were developed and validated for the quantitative determination of vecuronium bromide. The HPLC method was achieved on an amino column (Luna 150 × 4.6 mm, 5 μm) using UV detection at 205 nm. The mobile phase was composed of acetonitrile:water containing 25.0 mmol L?1 of sodium phosphate monobasic (50:50 v/v), pH 4.6 and flow rate of 1.0 mL min?1. The CZE method was achieved on an uncoated fused-silica capillary (40.0 cm total length, 31.5 cm effective length and 50 μm i.d.) using indirect UV detection at 230 nm. The electrolyte comprised 1.0 mmol L?1 of quinine sulfate dihydrate at pH 3.3 and 8.0% of acetonitrile. The results were used to compare both techniques. No significant differences were observed (p > 0.05). 相似文献
104.
Capillary electrophoresis separation of human milk neutral and acidic oligosaccharides derivatized with 2‐aminoacridone 下载免费PDF全文
Fabio Galeotti Giovanni V. Coppa Lucia Zampini Francesca Maccari Tiziana Galeazzi Lucia Padella Lucia Santoro Orazio Gabrielli Nicola Volpi 《Electrophoresis》2014,35(6):811-818
Human milk is a unique fluid in glycobiology due to the presence of many free structurally complex oligosaccharides emerging as important dietary factors during early life and having many biological and protective functions. Methods that allow accurate profiling of oligosaccharide mixtures in this complex biological fluid with quantification of the four known genetically determined groups are welcomed. A high‐voltage CE separation and detection at 254 nm of 17 neutral and acidic human milk oligosaccharide (HMO) standard along with lactose derivatized with 2‐aminoacridone, using a BGE containing 20% methanol as an organic modifier and borate, able to form on‐capillary anionic borate‐polyol complexes, is reported. This CE approach was able to separate both neutral HMOs and acidic HMOs, with the sialic acid residue, also in the presence of lactose in high content. This method was applied to the four secretory groups individually extracted by a rapid and simple preparative step. LODs were found ranging from ~50 to 700 fmol. We were able to measure HMO content also in the presence of excess fluorophore, or interference from proteins, peptides, salts, and other impurities normally present in this complex biological fluid. Overall, CE equipped with a UV detector is a common analytical approach and this simple CE separation offers high resolution and sensitivity for the differentiation of human milk samples related to genetic groups and days of lactation by considering that important changes in HMO content are a reflection of the lactation day. 相似文献
105.
Santoro A Prokhorov AM Kozhevnikov VN Whitwood AC Donnio B Williams JA Bruce DW 《Journal of the American Chemical Society》2011,133(14):5248-5251
Preparation of Ir(III) complexes using anisotropic 2,5-di(4-alkoxyphenyl)pyridine ligands leads to emissive, liquid-crystalline complexes containing bound Cl and dimethyl sulfoxide. Using analogous poly(alkoxy) ligands allows the preparation of bis(2-phenylpyridine)iridium(III) acac complexes, which are also mesomorphic. The observation of liquid crystallinity in octahedral complexes of this type is without precedent. 相似文献
106.
S. Serra S. Iarlori E. Tosatti S. Scandolo M. C. Righi G. E. Santoro 《Chemical physics letters》2002,360(5-6):487-493
We show, by electronic structure based molecular dynamics simulations, that an extra electron injected in crystalline polyethylene should fall spontaneously into a self-trapped state, a shallow donor with a large novel distortion pattern involving a pair of trans-gauche defects. Parallel calculations show instead that a hole will remain free and delocalized. We trace the difference of behavior to the intrachain nature of the hole, as opposed to the interchain one of the electron, and argue that applicability of this concept could be more general. Thus electrons (but not holes) should tend to self-trap in saturated organic insulators, but not for example in aromatic insulators, where both carriers are intrachain. 相似文献
107.
R. L. O. Rezende M. I. R. M. Santoro J. R. Matos 《Journal of Thermal Analysis and Calorimetry》2008,93(3):881-886
This paper demonstrates the application of thermal analysis in compatibility and stability studies between an ACE inhibitor
(enalapril maleate) and excipients. The results have helped to elucidate the reason of a stability problem observed during
the storage of enalapril maleate tablets. Incompatibility between enalapril maleate and colloidal silicon dioxide was detected.
Besides, it was confirmed that the reaction between enalapril maleate and NaHCO3 increases the thermal stability of the drug. This study supports the importance of using thermoanalytical methods in the
development of pharmaceuticals. 相似文献
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de Oliveira Maida Aysla Costa Ficca Valerio C. A. Gokhale Rohan Santoro Carlo Mecheri Barbara D’Epifanio Alessandra Licoccia Silvia Atanassov Plamen 《Journal of Solid State Electrochemistry》2021,25(1):93-104
Journal of Solid State Electrochemistry - In this work, we initially report a detailed advancement in the utilization of metal-N4 chelate macrocycles in the oxygen reduction reaction (ORR). Then,... 相似文献