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51.
Antonio Vita Cristina Italiano M. Arsalan Ashraf Lidia Pino Stefania Specchia 《International Journal of Hydrogen Energy》2018,43(26):11731-11744
In this study, the syngas production by steam reforming (SR) and oxy-steam reforming (OSR) of clean biogas over cordierite monoliths (400 cpsi) lined with Ni, Rh, or Pt on CeO2 catalyst was deeply investigated. Structured catalysts were prepared by using an alternative method to traditional washcoating based on the combination of the solution combustion synthesis (SCS) with the wetness impregnation (WI) technique. TEM and SEM analysis were used to study the morphology of the catalytic layer and to determine its thickness, while the quality of the coating in terms of adhesion on the monolith was evaluated by ultrasonic treatment in isopropyl alcohol solution. The performance and the stability of the structured catalysts were investigated at different process parameters, namely temperature (700–900 °C), steam-to-carbon (S/C = 1–5) and oxygen-to-carbon (O/C = 0.1–0.2) molar ratios, and weight space velocity (WSV = 30,000–250,000 NmL gcat?1 h?1). The SCS + WI deposition method allowed obtaining a uniform and thin coated layer with high mechanical strength. The following order of activity was exploited: Rh > Pt > Ni for biogas SR and Rh > Pt ≈ Ni for biogas OSR. The Rh-based catalyst exhibited higher activity and long-lasting stability towards biogas SR and OSR reactions for syngas production. 相似文献
52.
C. Italiano N.T.J. Luchters L. Pino J.V. Fletcher S. Specchia J.C.Q. Fletcher A. Vita 《International Journal of Hydrogen Energy》2018,43(26):11755-11765
A series of high specific surface area mesoporous supports (CeO2, CeO2-Al2O3, and Al2O3) were synthesized by the surfactant-assisted precipitation method using cetyltrimethylammonium bromide (CTAB) as template. Highly dispersed Rh-based catalysts were prepared by the wetness impregnation technique. The physico-chemical properties of the as-prepared supports and catalysts were investigated by N2-physisorption, CO-chemisorption, XRD, and H2-TPR measurements. Catalytic performance was evaluated towards the methane steam reforming (MSR) reaction up to 300 h of time-on-stream varying temperature (700–800 °C), steam-to-carbon (S/C = 2–3), and space velocity (88–200 SL·gcat?1·h?1); turnover frequencies were calculated at each reaction condition. All catalysts exhibited high activity strictly connected with high specific surface area (105–325 m2 g?1) and metal dispersion (34.3–84.0%). Significant enhanced stability was observed for Al2O3-containing catalysts towards the MSR reaction at high space velocity. 相似文献
53.
Anna Osello Andrea Acquaviva Chiara Aghemo Laura Blaso Daniele Dalmasso David Erba Giovanni Fracastoro Damien Gondre Marco Jahn Enrico Macii Edoardo Patti Anna Pellegrino Paolo Piumatti Ferry Pramudianto Jerôme Savoyat Maurizio Spirito Riccardo Tomasi Joseph Virgone 《Energy Efficiency》2013,6(4):707-723
In this paper, we report a methodology, developed in the context of Smart Energy Efficient Middleware for Public Spaces European Project, aimed at exploiting ICT monitoring and control services to reduce energy usage and CO2 footprint in existing buildings. The approach does not require significant construction work as it is based on commercial-off-the-shelf devices and, where present, it exploits and integrates existing building management systems with new sensors and actuator networks. To make this possible, the proposed approach leverages upon the following main contributions: (a) to develop an integrated building automation and control system, (b) to implement a middleware for the energy-efficient buildings domain, (c) to provide a multi-dimensional building information modelling-based visualisation, and (d) to raise people’s awareness about energy efficiency. The research approach adopted in the project started with the selection, as case studies, of representative test and reference rooms in modern and historical buildings chosen for having different requirements and constraints in term of sensing and control technologies. Then, according to the features of the selected rooms, the strategies to reduce the energy consumptions were defined, taking into account the potential savings related to lighting, heating, ventilation, and air conditioning (HVAC) systems and other device loads (PC, printers, etc.). The strategies include both the control of building services and devices and the monitoring of environmental conditions and energy consumption. In the paper, the energy savings estimated through simulation, for both HVAC and lighting, are presented to highlight the potential of the designed system. After the implementation of the system in the demonstrator, results will be compared with the monitored data. 相似文献
54.
Oil mixtures of medium-chain triglycerides (MCT) and D-limonene in mixing ratios from 10 to 100 wt% were encapsulated in modified starch (wall material) by spray drying to produce oil-rich powders. The oil load (mass ratio of oil mixture to wall material) of the infeed emulsion markedly influenced the properties of the infeed liquid and the characteristics of the resulting powder. The viscosity of the infeed liquid and the particle size of the powder exponentially decreased with increasing oil load, while the emulsion droplet size in the infeed liquid increased. In addition, retention of D-limonene during spray drying also decreased markedly with increasing oil load. Irrespective of the different oil loads and concentrations of the wall material, D-limonene retention was well correlated with the emulsion droplet diameter of the infeed liquid. The encapsulation efficiency of the oil mixture exhibited a maximum value (almost 100%) at an oil load between 0.5 and 1.0, before decreasing at higher oil loads. At an oil load of 2.0, the encapsulation efficiency of D-limonene was reduced to almost zero, while around 40% of the initial MCT was encapsulated in the powder. The increase in oil load also led to increased amounts of surface oil of MCT and D-limonene in the resulting powder due to the increasing emulsion droplet diameter of the infeed liquids. PRACTICAL APPLICATION: This study proposes the microencapsulation of medium-chain triglycerides under high-oil-load conditions by spray drying. The powders prepared by this process provide significant benefits in terms of rapid energy conversion after consumption without accumulation in the body. Important quality factors of the powder products such as the encapsulation efficiency and the amount of surface oil were examined to understand the optimum process conditions for spray drying. 相似文献
55.
56.
Antonio Vita Giuseppe Cristiano Cristina Italiano Stefania Specchia Francesco Cipitì Vito Specchia 《International Journal of Hydrogen Energy》2014
The in situ deposition of 1.5 wt.% Ru/γ-Al2O3 catalytic layers on cordierite monoliths (400 cpsi, diameter 1 cm, length 1.5 cm), combining Solution Combustion Synthesis (SCS) with Wet Impregnation (WI), was addressed. First of all, the physicochemical properties of the catalyst at powder level were investigated by X-ray Diffraction (XRD), N2 adsorption (BET), and H2 chemisorption, while the morphology of final structured catalysts was evaluated by SEM analysis and mechanical strength tests by sonication. The catalytic activity towards methane Oxy-Steam Reforming (OSR) reaction was studied after the choice of the most suitable catalyst load, carrying out tests varying the temperature (500–800 °C), the oxygen-to-carbon ratio (O/C = 0.45–0.75, oxygen as moles), the steam-to-carbon ratio (S/C = 1.0–2.4), and the weight space velocity (WSV = 34,000–400,000 N ml gcat−1 h−1), in order to identify the optimum operative conditions. The results showed that a total catalytic layer load (active metal plus oxide carrier) equal to 6.5 mg cm−2 was enough to achieve excellent performances, while no substantial improvements were obtained at higher catalytic layer loads. Moreover, the coated Ru/γ-Al2O3 monolith exhibited a good catalytic activity towards the studied reaction also at considerably high WSV values (till 400,000 N ml gcat−1 h−1). 相似文献
57.
58.
Joseph Rittenhouse Roshelle Wijeratne E. Bruce Orler David A. Dillard Robert B. Moore Raffaella De Vita 《Polymer Engineering and Science》2019,59(2):311-322
This study proposes a novel method to mechanically characterize the performance of individual bonds in low‐density, thermomechanically bonded nonwoven fabrics. Commercial bicomponent, polyethylene/polypropylene (PE/PP), nonwoven fabric was laser cut into bowtie‐shaped specimens for uniaxial tensile testing so that the central region of each specimen contained an individual bond. Three groups, each composed of 20 specimens, were tested with their longitudinal axes oriented along the machine direction (MD), the cross direction (CD), and at 45° between these two directions (DD). Prior to testing, the intrinsic variation in areal density and fiber orientation in the region surrounding the individual bond were quantified via orientation and relative basis weight parameters. During testing, images of the specimens were acquired to determine the occurrence of fiber breakage, bond deformation, and bond cohesive failure. Maximum force, stiffness, and orientation parameters were found to be significantly different among the three specimen groups (p < 0.01) but the relative basis weight was not (p > 0.01). The stiffness and maximum load were linearly correlated with both the areal density and fiber orientation. Pre‐existing voids or windows within the bond lowered the maximum force for specimens with the longitudinal axes aligned with the MD. These voids had no influence on the maximum force achieved by the specimens aligned with the CD and DD. The bonds in these specimens were observed to deform less than the bonds in the specimens with the longitudinal axes aligned with the MD. The results indicate the importance of the fiber structure surrounding the bond on the tensile properties, deformation and failure mode of individual bonds within the nonwoven fabric. POLYM. ENG. SCI., 59:311–322, 2019. © 2018 Society of Plastics Engineers 相似文献
59.
Laura Bianchi Maria Sframeli Lorenza Vantaggiato Gian Luca Vita Annamaria Ciranni Francesca Polito Rosaria Oteri Eloisa Gitto Fabrizio Di Giuseppe Stefania Angelucci Antonio Versaci Sonia Messina Giuseppe Vita Luca Bini Mhammed Aguennouz 《International journal of molecular sciences》2021,22(9)
Spinal muscular atrophy (SMA) type 1 is a severe infantile autosomal-recessive neuromuscular disorder caused by a survival motor neuron 1 gene (SMN1) mutation and characterized by progressive muscle weakness. Without supportive care, SMA type 1 is rapidly fatal. The antisense oligonucleotide nusinersen has recently improved the natural course of this disease. Here, we investigated, with a functional proteomic approach, cerebrospinal fluid (CSF) protein profiles from SMA type 1 patients who underwent nusinersen administration to clarify the biochemical response to the treatment and to monitor disease progression based on therapy. Six months after starting treatment (12 mg/5 mL × four doses of loading regimen administered at days 0, 14, 28, and 63), we observed a generalized reversion trend of the CSF protein pattern from our patient cohort to that of control donors. Notably, a marked up-regulation of apolipoprotein A1 and apolipoprotein E and a consistent variation in transthyretin proteoform occurrence were detected. Since these multifunctional proteins are critically active in biomolecular processes aberrant in SMA, i.e., synaptogenesis and neurite growth, neuronal survival and plasticity, inflammation, and oxidative stress control, their nusinersen induced modulation may support SMN improved-expression effects. Hence, these lipoproteins and transthyretin could represent valuable biomarkers to assess patient responsiveness and disease progression. 相似文献
60.
Rosanna Papa Stefania Garzoli Gianluca Vrenna Manuela Sabatino Filippo Sapienza Michela Relucenti Orlando Donfrancesco Ersilia Vita Fiscarelli Marco Artini Laura Selan Rino Ragno 《International journal of molecular sciences》2020,21(23)
Bacterial biofilm plays a pivotal role in chronic Staphylococcus aureus (S. aureus) infection and its inhibition may represent an important strategy to develop novel therapeutic agents. The scientific community is continuously searching for natural and “green alternatives” to chemotherapeutic drugs, including essential oils (EOs), assuming the latter not able to select resistant strains, likely due to their multicomponent nature and, hence, multitarget action. Here it is reported the biofilm production modulation exerted by 61 EOs, also investigated for their antibacterial activity on S. aureus strains, including reference and cystic fibrosis patients’ isolated strains. The EOs biofilm modulation was assessed by Christensen method on five S. aureus strains. Chemical composition, investigated by GC/MS analysis, of the tested EOs allowed a correlation between biofilm modulation potency and putative active components by means of machine learning algorithms application. Some EOs inhibited biofilm growth at 1.00% concentration, although lower concentrations revealed different biological profile. Experimental data led to select antibiofilm EOs based on their ability to inhibit S. aureus biofilm growth, which were characterized for their ability to alter the biofilm organization by means of SEM studies. 相似文献