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591.
Laska Aleksandra Szkodo Marek Cavaliere Pasquale Moszczyńska Dorota Mizera Jarosław 《Metallurgical and Materials Transactions A》2023,54(1):211-225
Metallurgical and Materials Transactions A - The Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and... 相似文献
592.
The increasing rotational speeds and the weight reduction of high‐performance internal combustion engines are accompanied by problems of lubrication, heat transfer, and vibration that are mostly negligible in medium‐ and low‐performance engines. To deal with such phenomena under demanding operating conditions necessitates a specific design. The dynamics of the power system between crankshaft and related sub‐components, e. g., bending and torsional vibrations of the connecting rod, ovalisation of the head and eye of the connecting rod, and vibrations of thin cylinder liners, are critical for the lubrication system in general, and for oil film pressure fields in particular. In some cases, no information on these features has existed until now, so no quantification of the variables involved has been possible. Over the last few years a systematic investigation has been performed to take into account the critical points and their fundamental importance in the design of such engines. The present paper considers some of the phenomena related to lubrication in high‐performance engines. The need is highlighted for further investigations using computational and experimental methodologies. 相似文献
593.
Antonella Pasqualone Samuela Palombieri Hamit Koksel Carmine Summo Pasquale De Vita Francesco Sestili 《International Journal of Food Science & Technology》2023,58(1):268-278
Faridur is the first ‘soft kernel’ durum wheat variety released in Italy. This variety has not yet been evaluated for its end-use quality. In the present study, the milling performance (using two different mills) and bread-making ability of Faridur were compared with Svevo. An effect of the mill type on flour properties was observed, with the Chopin CD1 mill leading to finer particle size, higher starch damage and water absorption than Bühler MLU 202. Protein and gluten content was significantly higher in Faridur, but gluten quality was lower, as indicated by alveograph and farinograph analyses. The softer nature of Faridur facilitated milling, reducing energy consumption and starch damage. The baking test led to a compact product, with low specific volume, needing adjustments in processing and formulation. As energy saving has become a key competitive factor in the milling sector, Faridur has potential for expanding the use of durum wheat. 相似文献
594.
The present study deals with the analyses of the direct reduction kinetics during the hydrogen reduction of industrial iron oxide pellets. Various types of pellets with different percentage of total iron content and metal oxides are examined. They are reduced at different temperatures and pressure (700–1100 °C and 1–6 bar) in hydrogen atmosphere. The reduction behavior is described in terms of time to reduction, rate of reduction, and kinetics constant. All the obtained results are analyzed through the employment of a commercial multiobjective optimization tool to precisely define the weight that each single parameter has on the reduction behavior. It is shown that from the point of view of the processing conditions, temperature is the main factor influencing the time to total reduction. From the point of view of the pellets properties, it is mainly influenced by the total iron percentage and then by porosity and basicity index. Also, the kinetics behavior is largely influenced by the reduction temperature even if it is mainly governed by the porosity and pores size from the point of view of the reduced pellets. The reduction rate is also mainly influenced by temperature and then by iron percentage, gas pressure, basicity index, and porosity. 相似文献
595.
Mariagrazia Di Luca Ensieh Poursani Manuela Curcio Giuseppe Cirillo Antonietta Salerno Sara Bolognini Giovanni De Filpo Sara Filippi Orazio Vittorio Francesca Iemma Fiore Pasquale Nicoletta 《大分子材料与工程》2023,308(11):2300166
With the objective of creating an electro-responsive and antimicrobial device suitable as delivery system for Rose Bengal (RB) to the skin, a hybrid hydrogel combining Chitosan (CS) and Graphene Oxide (GO) are designed, serving as functional polymer support and active filling element, respectively. The hybrid system, synthesized using tripolyphosphate as a crosslinker via ionic gelation, shows a uniform and homogeneous surface, as verified by SEM investigations, high biocompatibility when tested on human fibroblast lung cells MRC-5 cells, and biodegradability in phosphate buffered medium at physiological pH. Drug loading and release experiments, extensively analyzed using suitable mathematical modeling, shows the enhancement of the binding efficiency conferred by GO (534 and 979 mg g−1 for blank and hybrid hydrogels, respectively) and an electro-responsive behavior (maximum BR release of 36 and 23% at 0 and 12 V, respectively). Additionally, hybrid hydrogel is found to prevent the adhesion of methicillin-resistant Staphylococcus aureus and to kill the bacterial cells by taking advantage of the sustained release of the antimicrobial RB. 相似文献
596.
Rosa Ester Forgione Ferran Fabregat Nieto Cristina Di Carluccio Francesco Milanesi Martina Fruscella Francesco Papi Cristina Nativi Antonio Molinaro Pasquale Palladino Simona Scarano Maria Minunni Marco Montefiori Monica Civera Sara Sattin Oscar Francesconi Roberta Marchetti Alba Silipo 《Chembiochem : a European journal of chemical biology》2022,23(10):e202200076
Here, two conformationally constrained sialyl analogues were synthesized and characterized in their interaction with the inhibitory Siglec, human CD22 (h-CD22). An orthogonal approach, including biophysical assays (SPR and fluorescence), ligand-based NMR techniques, and molecular modelling, was employed to disentangle the interaction mechanisms at a molecular level. The results showed that the Sialyl-TnThr antigen analogue represents a promising scaffold for the design of novel h-CD22 inhibitors. Our findings also suggest that the introduction of a biphenyl moiety at position 9 of the sialic acid hampers canonical accommodation of the ligand in the protein binding pocket, even though the affinity with respect to the natural ligand is increased. Our results address the search for novel modifications of the Neu5Ac-α(2-6)-Gal epitope, outline new insights for the design and synthesis of high-affinity h-CD22 ligands, and offer novel prospects for therapeutic intervention to prevent autoimmune diseases and B-cell malignancies. 相似文献
597.
Elisa Calabrese Liberata Guadagno Marialuigia Raimondo Andrea Sorrentino Simona Russo Pasquale Longo Annaluisa Mariconda 《大分子材料与工程》2023,308(3):2200500
The synthesis and characterization of polyethylene glycol monomethyl ether methacrylate (PEGMA) based copolymers incorporating three different percentages (2.5 wt%, 5.0 wt%, and 7.8 wt%) of urea-N-2-amino-4-hydroxy-6-methylpyrimidine-N’-(hexametylen-n-carboxyethyl methacrylate) (HEMA-UPy) are reported. Nuclear magnetic resonance (NMR) and infrared spectroscopy (IR) confirm the synthesis procedure. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) are employed to evaluate the thermal properties of the samples. DSC measurements evidence a slight increase in glass transition temperature (Tg), a consistent increase in crystallization and melting temperatures (Tc and Tm), and a reduction in the crystallization degree (Xc) with increasing the amount of HEMA-UPy moiety. Dynamic mechanical analysis (DMA) is carried out at different values of temperature and oscillation frequency. It highlights the ability of the healed copolymer to recover the pristine values of storage modulus. The healing efficiency depends on the temperature history of the sample. For the sample healed at room temperature, the value of healing efficiency is 64%. DMA tests performed at higher temperatures, after some permanence at room temperature, evidence higher values in the healing efficiency. This demonstrates that the higher value of the temperature employed during DMA tests determines greater mobility of the chains causing an enhancement in the healing efficiency. 相似文献