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721.
Michele Dassisti Francesco Maddalena Alessio Brancolini Michela Chimienti Luca Granieri 《Optimization and Engineering》2013,14(1):155-174
The quality assessment of manufacturing operations performed to obtain given flat surfaces is always a problem of comparing the substitute model (approximating the features of the true manufactured part) to the nominal specifications, at any stage of the manufacturing cycle. A novel methodology, based on applications of classical tools of Calculus of Variations, is here presented with the aim of assessing the output quality of manufactured flat surfaces based on the information available on transformation imposed by technological processes. By assuming that any manufacturing process operates under equilibrium states, the proposed variational methodology allows to account for the traces left by different stages of manufacturing processes. A simple two-dimensional case is here discussed, to give the flavor of the methodology and its future potential developments. 相似文献
722.
723.
Ai Tran HN Sousa F Moda F Mandal S Chanana M Vimercati C Morbin M Krol S Tagliavini F Legname G 《Nanoscale》2010,2(12):2724-2732
Gold nanoparticles coated with oppositely charged polyelectrolytes, such as polyallylamine hydrochloride and polystyrenesulfonate, were examined for potential inhibition of prion protein aggregation and prion (PrPSc) conversion and replication. Different coatings, finishing with a positive or negative layer, were tested, and different numbers of layers were investigated for their ability to interact and reduce the accumulation of PrPSc in scrapie prion infected ScGT1 and ScN2a cells. The particles efficiently hampered the accumulation of PrPSc in ScN2a cells and showed curing effects on ScGT1 cells with a nanoparticle concentration in the picomolar range. Finally, incubation periods of prion-infected mice treated with nanomolar concentrations of gold nanoparticles were significantly longer compared to untreated controls. 相似文献
724.
Carmela Russo Fernando Stanzione Antonio Tregrossi Michela Alfè Anna Ciajolo 《Combustion and Flame》2012,159(7):2233-2242
The sooting structure of premixed fuel-rich atmospheric pressure benzene flames burning at the same C/O molar ratio = 0.8 was studied in different temperature conditions (Tmax = 1720 K and 1810 K) by changing the cold gas velocity. Compositional profiles of gaseous and condensed phases, measured by probe sampling and chemical analysis, indicated that pyrolytic routes leading to higher soot formation are more favoured in the lower temperature conditions.The structural analysis of condensed phases, including condensed species and soot, has been carried out by using FT-IR and UV–Visible spectroscopy sensitive to the hydrogen bonding and carbon network, respectively.The very low hydrogenated character, as evaluated by FT-IR and elemental analysis, and the high aromatic/graphitic nature of the benzene soot, as shown by a detailed examination of UV–Visible spectral parameters, confirmed the effect of benzene fuel on the internal structure of soot particles already in the early stages of particle inception. 相似文献
725.
Emanuele Tosi Bruno Fedrizzi Michela Azzolini Fabio Finato Barbara Simonato Giacomo Zapparoli 《Food chemistry》2012
The effects of noble rot on the overall quality of Amarone wine, a “Passito” dry red wine, produced by a traditional withering grape process are poorly understood. Wines obtained from healthy and selected grapes infected by noble rot were compared. Validation of the experimental plan was carried out by determining glycerol and gluconic acid content, laccase activity and microbial analysis of the musts. Botrytis cinerea infection produced significant variation in esterase and β-glucosidase activity of grape must. Aroma analysis in healthy and botrytised wines was carried out by SPE extraction followed by GC–MS quantification. A decrease of several fermentative esters was observed in botrytised wine, while wine produced from healthy grapes showed a higher fatty acid content. Molecules such as 1-octen-3-ol, phenylacetaldehyde and furaneol were positively linked to the noble-rotten grapes. Interestingly, γ-nonalactone and 4-carbethoxy-γ-butyrolactone increased, while sherry lactones decreased in botrytised wine. The strong increase of N-(3-methylbutyl)acetamide was related to B. cinerea grape infection. 相似文献
726.
Silvia Franchini Dr. Annalisa Tait Prof. Adolfo Prandi Dr. Claudia Sorbi Dr. Rossella Gallesi Michela Buccioni Dr. Gabriella Marucci Prof. Carla De Stefani Dr. Antonio Cilia Dr. Livio Brasili Prof. 《ChemMedChem》2009,4(2):196-203
A selective 5‐HT 1A receptor agonist : A new series of ligands acting at 5‐HT1A serotonin receptor were identified. Among them (2,2‐diphenyl‐[1,3]oxathiolan‐5‐yl‐methyl)‐(3‐phenyl‐propyl)amine (shown) possesses outstanding activity (pKi=8.72, pD2=7.67, Emax=85) and selectivity (5‐HT1A/α1D>150), and represents a new 5‐HT1A agonist chemotype.
727.
This paper presents the results from an extensive experimentation on polyester chips heating, crystallization and upgrading in three different size spouted bed units: a cylindrical 0.15 m diameter × 1.3 m tall, a 0.35 m square‐based × 2.1 m tall parallelepiped and a sextuple multi‐spouting 0.7 × 1.05 m2 demonstration reactor for solid state post‐polymerization. The first apparatus was finalized to measuring several process operating variables (maximum gas temperature at the inlet, overall heat transfer coefficient and particle agglomeration tendency); the second unit provided the hydrodynamical data necessary to scale‐up the system, insert into a PET upgrading process of 30 ton/day operating capacity and partially replace a bubbling fluidized bed heating/crystallizing unit. The ultimate goal of the project consisted in intensifying the process design by saving gas compression and thermal energy. The hydrodynamical findings of the squared modular unit were compared against several existing correlations: Manurung's equations for the maximum pressure drop and the pressure drop at stable spouting required a minimal alteration; Mathur and Gishler's equation properly fitted the experimental minimum spouting velocity. The continuously operating multiple spouting apparatus showed that regulating the solids level was an issue mainly due to the very large particle throughput, if related to the mixing efficiency of each module; reciprocal interference between spouted bed cells was manifested. 相似文献
728.
Mario Bocciolini Antonio Conti Giuliano di Caporiacco Giuliano Parrini Angela Quareni Vignudelli 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,240(1):36-42
A position sensitive detector for minimum ionizing particles is described. It is based on charge coupled devices (CCDs) area image sensors with single pixel sizes of 22 × 22 μm2. The operating frequency is 6.75 MHz and the total readout time for 2.3 × 105 pixels is about 40 ms. The devices are operated close to room temperature. 相似文献
729.
B Di Jeso A Feliciello F Pacifico A Iannelli F D'Armiento D Liguoro P Giuliano G Ferulano EV Avvedimento 《Canadian Metallurgical Quarterly》1995,6(10):1315-1319
Differentiated thyroid cells expressing polyoma Middle-T became transformed and tumorigenic when injected into syngenic animals. The expression of thyroglobulin was greatly reduced and no longer responsive to thyrotropin (TSH) and to cAMP. Inhibition of endogenous c-ras by the expression of two transdominant negative mutant H-ras genes, Asn17 and Leu61-Ser186, reactivated thyroglobulin synthesis. Reactivation of thyroglobulin synthesis by c-ras inhibition was not observed in the absence of TSH. These findings indicate that MT elicits dedifferentiation of thyroid cells by activating endogenous c-ras and that c-ras interferes with TSH or cAMP signaling. 相似文献
730.
Y Tang O Rampin A Calas P Facchinetti F Giuliano 《Canadian Metallurgical Quarterly》1998,82(1):241-254
Penile erection is due to activation of proerectile neurons located in the sacral parasympathetic nucleus of the L6-S1 spinal cord in the rat. Contraction of the ischiocavernosus and bulbospongiosus striated muscles, controlled by motoneurons located in the ventral horn of the L5-L6 spinal cord, reinforces penile erection. Physiological and pharmacological arguments have been provided for a role of oxytocin and serotonin in the spinal regulation of penile erection. Immunohistochemistry of oxytocinergic and serotonergic fibres was performed at the lumbosacral level of the male rat spinal cord, and combined with retrograde tracing from the pelvic nerve or from the ischiocavernosus and bulbospongiosus muscles using wheat germ agglutinin-horseradish peroxidase. Sacral preganglionic neurons retrogradely labelled from the pelvic nerve formed a homogeneous population, predominant at the L6 level. Motoneurons retrogradely labelled from the ischiocavernosus and bulbospongiosus muscles were observed in the medial part of the dorsolateral and in the dorsomedial nuclei. Fibres immunoreactive for oxytocin were mainly distributed in the superficial layers of the dorsal horn, the dorsal gray commissure and the sacral parasympathetic nucleus. Some of these fibres were apposed to retrogradely-labelled sacral preganglionic neurons and at the ultrastructural level, some synapses were evidenced. Fibres immunoreactive for serotonin were largely and densely distributed in the dorsal horn, the dorsal gray commissure, the sacral parasympathetic nucleus and the ventral horn. Some serotonergic fibres occurred in close apposition with retrogradely-labelled sacral preganglionic neurons and motoneurons, and synapses were demonstrated at the ultrastructural level. This study provides morphological support for a role of oxytocin and serotonin on sacral preganglionic neurons innervating pelvic organs and motoneurons innervating the ischiocavernosus and bulbospongiosus muscles. 相似文献