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41.
Antonino Valenza Vincenzo Fiore Livan Fratini 《The International Journal of Advanced Manufacturing Technology》2011,53(5-8):593-600
In this paper, the influence of several parameters on the mechanical behaviour and failure modes of hybrid bonded joints aluminium/composite was investigated. Particularly, the effects of metallic surface condition, adhesive properties and thickness on single-lap joint resistance were analysed. To these aims, two adhesives were used and, for each adhesive, two different adhesive thicknesses (0.5 and 1.5?mm) have been investigated. Furthermore, two sets of joints for each adhesive kind and thickness were investigated: the former was obtained using aluminium blanks which were previously mechanically treated with sandpaper (P60) and the latter using aluminium treated with sandpaper and with presence of fillets in the ends of the overlap area. In order to improve the adhesion strength between polymeric adhesive and aluminium, two metal surface treatments have also been performed using a silane coupling agent, ??-glycidoxypropyltrimethoxysilane (??-GPS). The mechanical performances and failure modes were found to be significantly increased using the chemical pre-treatments with ??-GPS silane coupling agent unlike other parameters investigated. As regard the thickness of the adhesive layer, the better value is found to be equal to 0.5?mm, for both adhesives investigated. 相似文献
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44.
Martino Di Serio Riccardo Tesser Vincenzo Russo Rosa Turco Rosa Vitiello Yongqiang Sun Wiesław Hreczuch 《Journal of surfactants and detergents》2015,18(5):913-918
The intermediates for the production of nonionic surfactants can be derived from petrochemicals and/or from renewable raw materials. In both, the role of catalysis is fundamental. In this paper the main results reported in the literature related with the catalysis for ethoxylation of fatty esters will be reviewed. The main open challenges for these technologies will be outlined. 相似文献
45.
Vincenzo Petrozza Antonio Carbone Teresa Bellissimo Natale Porta Giovanni Palleschi Antonio Luigi Pastore Angelina Di Carlo Carlo Della Rocca Francesco Fazi 《International journal of molecular sciences》2015,16(12):29219-29225
A key challenge for the improvement of clear cell renal cell carcinoma (ccRCC) management could derive from a deeper characterization of the biology of these neoplasms that could greatly improve the diagnosis, prognosis and treatment choice. The aim of this study was to identify specific miRNAs that are deregulated in tumor vs. normal kidney tissues and that could impact on the biology of ccRCC. To this end we selected four miRNAs (miR-21-5p, miR-210-3p, miR-185-5p and miR-221-3p) and their expression has been evaluated in a retrospective cohort of formalin-fixed paraffin-embedded (FFPE) tissues from 20 ccRCC patients who underwent surgical nephrectomy resection. miR-21-5p and miR-210-3p resulted the most significantly up-regulated miRNAs in this patient cohort, highlighting these onco-miRNAs as possible relevant players involved in ccRCC tumorigenesis. Thus, this study reports the identification of specific oncogenic miRNAs that are altered in ccRCC tissues and suggests that they might be useful biomarkers in ccRCC management. 相似文献
46.
新村空间设计语汇模块化是村落景观设计较为普遍的现象,也是地域特征弱化和空间不契合空间行为等问题的主要原因之一。古村落宅间元素是村民日常生活与村落环境在相互影响下长期适应性发展的结果,宅间元素模式研究可促进丰富新村空间设计语汇。以徽州地区古村落为例,从宅间元素的分类、图示、与空间行为的关联3个方面论述了古村落宅间元素模式研究方法论。通过徽州茆田新村景观设计阐述了宅间元素模式的应用,论述了基于古村落宅间元素模式的村落景观设计优化策略,有益于形成并推广地方空间设计语汇,避免过度依赖和使用既有的、来自城市的广场、草坪、树池等元素造成的全国村落的无差别设计。 相似文献
47.
Vincenzo Di Marzo Mikko Griinari Gianfranca Carta Elisabetta Murru Alessia Ligresti Lina Cordeddu Elena Giordano Tiziana Bisogno Maria Collu Barbara Batetta Sabrina Uda Kjetil Berge Sebastiano Banni 《International Dairy Journal》2010,20(4):231-235
Evidence suggests that dietary long chain polyunsaturated fatty acids (LCPUFAs), and particularly those belonging to the n-3 family, may influence the brain fatty acid profile and, thereby, the biosynthesis of endocannabinoids in rodents. However, the doses used are usually quite high and not comparable with human intake. Recently, we have shown that relatively low doses of dietary n-3 LCPUFAs (4 weeks), in the form of either fish or krill oil, balanced for EPA and DHA content, and against a control diet with no EPA and DHA and similar contents of oleic, linoleic and α-linolenic acids, lower the concentrations of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in the visceral adipose tissue, and of AEA in the liver and heart, of obese Zucker rats. This, in turn, is associated with lower levels of arachidonic acid in membrane phospholipids and with amelioration of some metabolic syndrome parameters. We investigated here whether in Zucker rats, under the same conditions, fish and krill oil are also able to influence LCPUFA and endocannabinoid profiles in brain. Only krill oil was able to increase significantly DHA levels in brain phospholipids, with no changes in arachidonic acid. DHA increase was associated with lower levels of 2-AG in the brain, whereas AEA and its congeners, N-palmitoylethanolamine and N-oleoylethanolamine, were unchanged. We conclude that, despite the strong impact of dietary n-3 fatty acid on endocannabinoid levels previously observed in peripheral tissues, in the brain only 2-AG is affected by dietary krill oil, suggesting that the beneficial effect of the latter on the metabolic syndrome is mostly exerted by modifying peripheral endocannabinoids. Nevertheless, possible effects of dietary krill oil in the brain through modification of 2-AG levels deserve further investigation. 相似文献
48.
Vincenzo Calemma Chiara Gambaro Wallace O. Parker Rosa Carbone Roberto Giardino Pietro Scorletti 《Catalysis Today》2010,149(1-2):40-46
A light cobalt catalyzed Fischer–Tropsch (FT) wax was subjected to hydrocracking in the range of temperature 319–351 °C and hydrogen pressure between 3.5 and 6.0 MPa. The catalyst used was platinum on amorphous silica–alumina. Hydrocracking reaction led to an increase of middle distillate yield up to 85% with a contemporary increase of iso-paraffins concentration which resulted in a remarkable improvement of cold flow properties of the products. The freezing point of C10–C14 fraction passed from ?23 to ?45 °C while the pour point of C15–C22 fraction decreased from 13 to ?23 °C. The latter fraction displayed high cetane numbers ranging between 75 and 80. Changes in carbon distribution and molecular structure of products during hydrocracking have been rationalized in the light of the accepted hydrocracking mechanism where n-paraffins undergo to consecutive isomerization reactions leading to isomers with progressively higher branching degree and concomitant cracking reaction. Experimental evidences support the view that apparent reactivity of n-paraffins is chain length dependent, increasing with the molecular weight. Detailed characterization by NMR and GC showed that branching groups abundance in the middle distillate products was the following: methyl ? ethyl > propyl.Emission tests carried out with FT diesel and commercial ultra low sulfur diesel showed that FT diesel has excellent combustion properties and leads to a reduction of emissions. 相似文献
49.
Giulio Giovannetti Francesca Frijia Simona Attanasio Luca Menichetti Valentina Hartwig Nicola Vanello Jan Henrik Ardenkjaer-Larsen Daniele De Marchi Vincenzo Positano Rolf Schulte Luigi Landini Massimo Lombardi Maria Filomena Santarelli 《Measurement》2013
Hyperpolarized 13C magnetic resonance spectroscopy in pig models enables cardiac metabolism assessment and provides a powerful tool for heart physiology studies, although the low molar concentration of derivate metabolites gives rise to technological limitations in terms of data quality. The design of dedicated coils capable of providing large field of view with high Signal-to-Noise Ratio (SNR) data is of fundamental importance. 相似文献
50.
The influence of axial fluid conduction on low Péclet number flows in the thermal entrance region of long circular tubes is investigated in this theoretical study. The convective heat transport of viscous fluids relates to a specific condition under which the first part of the tube ( x h 0) is insulated and the second part of the tube ( x > 0) receives a heat flux of uniform intensity. A conjugate one-dimensional lumped model produces a solution of compressed algebraic form that is able to deliver dependable mean bulk temperatures that are in perfect agreement with those obtained numerically by the formal conjugate two-dimensional distributed model. As a by-product of the succession of algebraic calculations within the platform of the lumped model, the critical Péclet number Pe cr has been easily quantified. This number is a figure-of-merit of remarkable importance in the modeling of forced heat convection in tubes because it establishes the threshold between two contrasting situations: one embracing axial fluid conduction (finite Pe) and the other implicating negligible axial fluid conduction (Pe M X ). In addition, the local wall temperatures were calculated with an approximate engineering procedure, showing good agreement with those determined numerically by the formal conjugate two-dimensional distributed model. 相似文献