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81.
Gian Domenico Sorarù Lakshminath Kundanati Balanand Santhosh Nicola Pugno 《Journal of the American Ceramic Society》2019,102(3):907-913
Silicon oxycarbide (SiOC) glasses in the form of thin, dense, and crack-free samples were fabricated according to the polymer pyrolysis route starting from cross-linked polysiloxane. The amount of free carbon in the final SiOC materials was varied in the range 18-60 vol%. The mechanical properties of the SiOC glasses were measured by nanoindentaion technique and revealed that both the Young's modulus and the hardness decrease with increase in the free carbon content and follow a simple rule of mixtures model. 相似文献
82.
Fabiana Piscitelli Roberto Coccurello Antonio Totaro Alessandro Leuti Giacomo Giacovazzo Roberta Verde Emanuela Rossi Michele Podaliri Vulpiani Nicola Ferri Roberto Giacominelli Stuffler Vincenzo Di Marzo Sergio Oddi Tiziana Bisogno Mauro Maccarrone 《European Journal of Lipid Science and Technology》2019,121(10)
83.
Lourdes Vázquez-Gómez Enrico Verlato Sandro Cattarin Nicola Comisso Paolo Guerriero Marco Musiani 《Electrochimica acta》2011,(5):2237
Electrocatalysts for methanol oxidation were prepared through a two stage deposition process: porous cobalt layers were deposited, by cathodic reduction of Co2+ ions, and then modified by spontaneous deposition of Pd. A basic sulphate solution and a mildly acid chloride solution were compared as media for the electrodeposition of Co. Deposits with the highest surface roughness were obtained in the chloride solution, at large current densities. Pd was deposited onto the Co porous layers by immersing them in acid deaerated PdCl2 solutions, at open circuit. The Pd loading and the Pd surface area were estimated by UV–visible spectroscopy and by cyclic voltammetry, respectively. The Pd-modified Co electrodes were tested as anodes for methanol oxidation and compared to the similarly prepared Pd-modified Ni electrodes. The former exhibited better stability of performance and higher methanol oxidation peak currents per unit Pd mass, ca. 200 A g−1. 相似文献
84.
Carlo Beatrice Chiara Guido Pierpaolo Napolitano Silvana Di Iorio Nicola Del Giacomo 《Fuel》2011,90(5):2039-2044
Results of a research project aimed at studying the capability to develop a method (economic and simple) for on-board biodiesel blending detection are described. The method is based on the direct measurement of the Indicated Mean Effective Pressure (IMEP).The study was carried out on a 2.0L four-cylinder “torque-controlled” Euro 5 diesel engine for passenger car (PC) application. This engine, equipped with instrumented glow plug for combustion closed-loop control, represents the state of the art of the diesel engine control technology.Two biodiesels were chosen for the experiments: a rapeseed methyl-ester (RME) and an aged RME, while the conventional diesel fuel was an European (EU) certification diesel fuel.Results indicate generally a good response in blending detection of the method. However, in order to attain an acceptable accuracy, a pre-calibration appears necessary. 相似文献
85.
The preparation of porous hierarchical architectures that have structural features spanning from the nanometer to micrometer and even larger dimensions and that exhibit certain functionalities is one of the new challenging frontiers in materials chemistry. The sol-gel process is one of the most promising synthesis routes toward such materials because it not only offers the possibility to incorporate organic functions into the porous host but also offers the possibility to deliberately tailor the pore structure. In this Account, the opportunities given by the application of novel diol-modified silanes are discussed for the synthesis of hierarchically organized inorganic and also inorganic-organic porous monoliths. 相似文献
86.
Immacolata Ruggiero Monica Terracciano Nicola M Martucci Luca De Stefano Nunzia Migliaccio Rosarita Tatè Ivo Rendina Paolo Arcari Annalisa Lamberti Ilaria Rea 《Nanoscale research letters》2014,9(1):329
Diatomite is a natural fossil material of sedimentary origin, constituted by fragments of diatom siliceous skeletons. In this preliminary work, the properties of diatomite nanoparticles as potential system for the delivery of drugs in cancer cells were exploited. A purification procedure, based on thermal treatments in strong acid solutions, was used to remove inorganic and organic impurities from diatomite and to make them a safe material for medical applications. The micrometric diatomite powder was reduced in nanoparticles by mechanical crushing, sonication, and filtering. Morphological analysis performed by dynamic light scattering and transmission electron microscopy reveals a particles size included between 100 and 300 nm. Diatomite nanoparticles were functionalized by 3-aminopropyltriethoxysilane and labeled by tetramethylrhodamine isothiocyanate. Different concentrations of chemically modified nanoparticles were incubated with cancer cells and confocal microscopy was performed. Imaging analysis showed an efficient cellular uptake and homogeneous distribution of nanoparticles in cytoplasm and nucleus, thus suggesting their potentiality as nanocarriers for drug delivery.
PACS
87.85.J81.05.Rm; 61.46. + w 相似文献87.
Roberta D’Ambrosio Alessio Aghemo Raffaele De Francesco Maria Grazia Rumi Enrico Galmozzi Stella De Nicola Cristina Cheroni Paul J. Clark Guido Ronchi Pietro Lampertico Massimo Colombo 《International journal of molecular sciences》2014,15(5):7213-7224
The interleukin 28B (IL28B) rs12979860 polymorphism is associated with treatment outcome in hepatitis C virus (HCV) genotype 1 and 4 patients. Its association with the histological features of chronic hepatitis C and disease severity needs further clarifications. To assess the correlation between IL28B genotype, HCV genotype and liver biopsy findings in untreated patients.
Materials and Methods
Pre-treatment liver biopsies from 335 HCV Caucasian patients (59% males, age 50 years) enrolled in the MIST study were staged for fibrosis and inflammation according to the METAVIR and the Ishak scoring systems; steatosis was dichotomized as <5% or ≥5%. IL28B was typed by Taqman Single Nucleotide Polymorphism (SNP) genotyping assay. HCV genotype was 1 in 151 (45%), 2 in 99 (30%), 3 in 50 (15%) and 4 in 35 (10%) patients. IL28B genotype was CC in 117 (34%), CT in 166 (49%) and TT in 52 (15%). At univariate analysis, the IL28B CC genotype was associated with severe portal inflammation in HCV-1 patients (CC vs. CT/TT: 86% vs. 63%, p = 0.005), severe lobular inflammation in HCV-2 patients (CC vs. CT/TT: 44% vs. 23%, p = 0.03), and less fatty infiltration in HCV-1 patients (CC vs. CT/TT: 72% vs. 51%, p = 0.02). Despite the lack of any association between IL28B and fibrosis stage, in HCV-3 patients IL28B CC correlated with METAVIR F3–F4 (CC vs. CT/TT: 74% vs. 26%, p = 0.05). At multivariate analysis, the genotype CC remained associated with severe portal inflammation in HCV-1, only (Odds Ratio (OR): 95% Confidence Interval (CI): 3.24 (1.23–8.51)). IL28B genotype is associated with the histological features of chronic hepatitis C in a HCV genotype dependent manner, with CC genotype being independently associated with severe portal inflammation. 相似文献88.
Belal Chami Nicola Barrie Xiaoping Cai Xiaosuo Wang Moumita Paul Rebecca Morton-Chandra Alexandra Sharland Joanne M. Dennis Saul B. Freedman Paul K. Witting 《International journal of molecular sciences》2015,16(5):11101-11124
The acute phase protein serum amyloid A (SAA), a marker of inflammation, induces expression of pro-inflammatory and pro-thrombotic mediators including ICAM-1, VCAM-1, IL-6, IL-8, MCP-1 and tissue factor (TF) in both monocytes/macrophages and endothelial cells, and induces endothelial dysfunction—a precursor to atherosclerosis. In this study, we determined the effect of pharmacological inhibition of known SAA receptors on pro-inflammatory and pro-thrombotic activities of SAA in human carotid artery endothelial cells (HCtAEC). HCtAEC were pre-treated with inhibitors of formyl peptide receptor-like-1 (FPRL-1), WRW4; receptor for advanced glycation-endproducts (RAGE), (endogenous secretory RAGE; esRAGE) and toll-like receptors-2/4 (TLR2/4) (OxPapC), before stimulation by added SAA. Inhibitor activity was also compared to high-density lipoprotein (HDL), a known inhibitor of SAA-induced effects on endothelial cells. SAA significantly increased gene expression of TF, NFκB and TNF and protein levels of TF and VEGF in HCtAEC. These effects were inhibited to variable extents by WRW4, esRAGE and OxPapC either alone or in combination, suggesting involvement of endothelial cell SAA receptors in pro-atherogenic gene expression. In contrast, HDL consistently showed the greatest inhibitory action, and often abrogated SAA-mediated responses. Increasing HDL levels relative to circulating free SAA may prevent SAA-mediated endothelial dysfunction and ameliorate atherogenesis. 相似文献
89.
90.
All controlled radical polymerization (CRP) procedures rely on a dynamic and rapid equilibrium between dormant and active species. This equilibrium can be established through different mechanisms and all the resulting CRP processes have their own advantages and limitations. Therefore, it becomes interesting to investigate the possibility of combining CRP techniques to eliminate specific drawbacks of each individual procedure. Atom transfer radical polymerization (ATRP) with alkyl pseudohalides acting as initiators and chain transfer agents was developed for that purpose. The process relies on a dual mechanism involving both activation deactivation and reversible addition fragmentation chain transfer (RAFT). This peculiar characteristic of ATRP with alkyl pseudohalides acting as chain transfer agents made it possible to overcome some of the limitations typically associated with conventional ATRP and RAFT polymerization as well as to prepare new responsive materials. 相似文献