Search results for "Solid"
showing 10 items of 3575 documents
Fossil Fuel and Biofuel Boilers in Ukraine: Trends of Changes in Levelized Cost of Heat
2022
An increase in the share of renewables in heat supply systems is a promising direction to reach sustainable development goals and decarbonization. Decision makers should consider various factors, including energy market prices, the availability of biofuels, boiler and auxiliary equipment costs, logistic costs, and the taxation system. In the European Union, the energy crisis causes a rapid increase in fossil fuel prices. Moreover, the use of fossil fuels results in greenhouse gas emissions, which threatens the achievement of sustainable development goals. We studied the influence of the delivery cost and the value of environmental tax rates on the levelized cost of heat. Low-capacity boiler…
A novel approach to enhance mechanical properties during recycling of aluminum alloy scrap through friction stir consolidation
2021
Solid state recycling (SSR) is a new approach for making metals recycling more efficient with respect to remelting-based approaches. Friction stir consolidation (FSC) is a new solid-state process that is employed to recycle metallic scraps. Until now, a single-step FSC process was applied to recycled metal chips. During the single-step approach, critical processes parameters, especially processing time and rotational speed, are considered vital to control the quality and mechanical properties of the billet. However, the effectiveness of process parameters is highly restricted by challenging masses of recycling chips and machine competency. The present study first highlights the issues of th…
Controllable Solid Rocket Motor Nozzle Operations in Conditions of Limited-Amplitude Fluctuations
2009
A nonlinear multi scale analysis of a controllable solid rocket motor operating in conditions ranging from high-amplitude fluctuations in combustion chamber to conditions lying in limit cycle is presented and the motor behavior subsequent to some relevant nozzle operations is investigated. Effects of acoustic-vorticity-entropy wave coupling, wave steepening, rotational/viscous flow losses, steep-fronted wave losses are taken into account and oscillatory energy losses in pintle-nozzle, unsteady combustion and chamber geometry changes resulting from grain regression are included. The analysis provides evidence that the unsteady energy balance and the motor wave amplitude evolution are influen…
Zinc(II) complexes of amide- and urea-substituted 8-hydroxyquinolines
2002
Abstract A series of amide- and urea-substituted 8-hydroxyquinoline ligands 1–6-H are used for the formation of zinc(II) complexes. Hereby in general 2:1 complexes are obtained and the X-ray structure of [(3)2Zn] reveals the presence of a coordination polymer in the solid state. Only the derivatives of 7-amino-8-hydroxyquinoline 4-H and 5-H form trinuclear hexa-helical 6:3 complexes which exhibit interesting structural and NMR and fluorescence spectroscopic properties.
Intergenerational support as a reaction to socio-economic crisis: alteration of solidarity within precarious Romanian households
2017
ABSTRACTThis paper addresses the tensions arising from the intersection of norms and practices of support in situations in which intergenerational support is the main household strategy for coping with precariousness in Romania. This paper describes competing meanings of solidarity and reveals gendered experiences of ambiguity with respect to the sustainability of help exchanges within the context of economic vulnerability. Romania displays high public acceptance of intergenerational support, while the country’s deficient social welfare system prompts families to intensify their help exchanges. Findings based on in-depth interviews suggest that private arrangements are compounded by unbalan…
Influence Of The Electrical Parameters On The Fabrication Of Copper Nanowires Into Anodic Alumina Templates
2009
Abstract Metallic copper nanowires have been grown into the pores of alumina membranes by electrodeposition from an aqueous solution containing CuSO 4 . and H 3 BO 3 at pH 3. In order to study the influence of the electrical parameters on growth and structure of nanowires, different deposition potentials (both in the region where hydrogen evolution reaction is allowed or not) and voltage perturbation modes (constant potential or unipolar pulsed depositions) were applied. In all cases, pure polycrystalline Cu nanowires were fabricated into template pores, having lengths increasing with the total deposition time. These nanowires were self-standing, because they retain their vertical orientati…
Template electrosynthesis of aligned Cu2O nanowires
2008
Abstract Large arrays of aligned copper oxide nanowires were produced by electrodeposition, using anodic alumina membranes as template. We have studied the effect of two fundamental parameters involved in fabrication process: potential perturbation and bath composition. Performing electrodeposition from a copper acetate/sodium acetate bath (pH 6.5), we found that chemical composition of nanowires varied in dependence on the shape of the applied potential perturbation: pure copper oxide nanowires were produced by pulsed potential, whilst continuous electrodeposition resulted in a co-deposition of Cu and Cu 2 O. In a copper lactate bath, buffered at pH 10, the shape of perturbation did not in…
?Contratti di soggiorno? e COVID-19. Parte prima. Nel periodo emergenziale.
2020
This paper analyses the destiny of ?sojourn contracts? (?contratti di soggiorno?) entered into prior to the outbreak of the Coronavirus pandemic, for services to be enjoyed during the emergency period. The work focuses, in particular, on the analysis of the emergency provisions introduced by the Italian legislator in favour of the tourism sector, by allowing professionals operating in the tourism sector to postpone the timing of the sojourn by issuing a voucher to be used in one year following the issuance date as an alternative to the reimbursement of any payment made prior to the emergency periods solutions in conformity with the principles of solidarity adopted in order to balance and sa…
Atti di disposizione del corpo e principio di gratuità
2008
Capitolo del volume “Il principio di gratuità” a cura di A. Galasso e S. Mazzarese, il saggio mette in rilievo un innovativo significato e ruolo del principio di gratuità come criterio ordinante degli atti di disposizione del proprio corpo e più in generale degli atti di autodeterminazione incidenti sulla sfera corporea della persona, quale emerge dalla disciplina esistente in ambito municipale e sovranazionale, evidenziandone la diversità rispetto a quello tradizionalmente sedimentatosi nel differente ambito delle relazioni a contenuto patrimoniale, in opposizione dialettica alle categorie dell’onerosità e della corrispettività.
FERULIC ACID INHIBITS OXIDATE STRESS AND CELL DEATH INDUCED BY Ab OLIGOMERS: IMPROVED DELIVERY BY SOLID LIPID NANOPARTICLES.
2009
Oxidative stress and dysfunctional mitochondria are among the earliest events in AD, triggering neurodegeneration. The use of natural antioxidants could be a neuroprotective strategy for blocking cell death. Here, the antioxidant action of ferulic acid (FA) on different paths leading to degeneration of recombinant beta-amyloid peptide (rAbeta42) treated cells was investigated. Further, to improve its delivery, a novel drug delivery system (DDS) was used. Solid lipid nanoparticles (SLNs), empty or containing ferulic acid (FA-SNL), were developed as DDS. The resulting particles had small colloidal size and highly negative surface charge in water. Using neuroblastoma cells and rAbeta42 oligome…