Search results for "On resistance"

DC01 steel corrosion resistance in cathodic polarization

2016

Celem prowadzonych badań było okreœlenie odporności korozyjnej stali DC01 poddanej katodowej polaryzacji w zmiennych warunkach. Elektrochemiczne pomiary służące do oceny odpornoœci korozyjnej stali nienawodorowanej poddanej katodowej polaryzacji przeprowadzono metodami obejmującymi pomiar potencjału obwodu otwartego i zarejestrowania zależności i=f(E) podczas badań polaryzacyjnych w trójelektrodowym układzie pomiarowym. Do pomiarów wykorzystano układ składający się z naczynka pomiarowego, potencjostatu AMEL PSW01 System 5000 oraz komputera z oprogramowaniem „CorrWare”. Wodorowanie stali zrealizowano w wodnym roztworze 0,1 N kwasu siarkowego(VI) z dodatkiem 2 mg/dm3 tlenku arsenu(III) jako p…

The Effects of Admixtures on Resistance to Radiation of Lithium Niobate Crystals

2015

The studies of optical absorption and transmission of crystalline lithium niobate compounds modified by rare-earth and alkali-earth elements: LiNbO3: Y (0.46 wt %), LiNbO3: Y (0.32 wt %), Mg (0.24 wt %), LiNbO3: Mg (0.27 wt %), LiNbO3: Gd (0.004, 0.04, 0.26, and 0.43 wt %), and ostensibly pure LiNbO3 is reported. The features of absorption and transmission are examined with respect to the dosage of γ-irradiation, the annealing temperature, and the type and concentration of modifying admixtures. The features revealed in different ways of bleaching γ-irradiated and annealed in vacuum ostensibly pure lithium niobate crystals are used to refine the mechanisms of developing electron and point de…

APPLICAZIONE DI UN PROTOTIPO DI MOTOVANGATRICE PER PRESERVARE LA FERTILITÀ DEL SUOLO

Negli ambienti caratterizzati da forti pendenze o sistemati a terrazze, nell’ambito delle lavorazioni superficiali, viene impiegato diffusamente il motocoltivatore provvisto di zappatrice rotativa. Tuttavia, l’effetto dell’uso ripetuto della zappatrice per lavorazione del terreno ha una notevole influenza sulle caratteristiche del terreno, che si presenta finemente polverizzato, soffice e astrutturato. Al fine di limitare tali inconvenienti, è stata progettata dalla sezione Meccanica del Dipartimento Scienze Agrarie e Forestali dell’Università di Palermo, in collaborazione con la ditta costruttrice Agrotec di Padova, una macchina innovativa semovente provvista di organi di lavoro del tipo a…

O2-Loading Treatment of Ge-Doped Silica Fibers: A Radiation Hardening Process

2016

International audience; The effects of a high-pressure O2-loading treatment on the radiation response of Ge-doped optical fibers (OFs) were investigated. We found that the incorporation of high concentration of interstitial molecular oxygen remarkably enhances the resistance to ionizing radiation of Ge-doped OFs in the UV-Visible domain and, at the same time, improves the transmission of UV light in the unirradiated OF sample. By comparison with previously reported results, the O2-loading treatment turned out to increase the radiation resistance of Ge-doped OFs more efficiently than F or Ce codoping. The understanding of such amelioration relies in basic radiation-induced mechanisms that we…

Effect of different soil management in sloping vineyards on soil penetration resistance.

2013

In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of rototilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the SAF (Scienze Agrarie e Forestali) Department of the University of Palermo in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of…

Soil physical-mechanical properties evaluation in different tillage systems

2014

In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of ro-totilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the Department of Agricultural and Forest Sciences, University of Palermo, in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of t…

Incorporation mechanism of colloidal TiO2 nanoparticles and their effect on properties of coatings grown on 7075 Al alloy from silicate-based solutio…

2021

Plasma electrolytic oxidation (PEO) was applied using a pulsed unipolar waveform to produce Al2O3-TiO2 composite coatings from sol electrolytic solutions containing colloidal TiO2 nanoparticles. The sol solutions were produced by dissolving 1, 3, and 5 g/L of potassium titanyl oxalate (PTO) in a silicate solution. Scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, and Raman spectroscopy were applied to characterizing the coatings. Corrosion behavior of the coatings was investigated using polarization and impedance techniques. The results indicated that TiO2 enters the coating through all types of micro-discharging and is doped into the alumina phase. The higher…

Effect of Molybdate on Corrosion Performance of Oxide Coating Produced on 7075 Al Alloy Using PEO

2022

In this research, plasma electrolytic oxidation (PEO) coatings were prepared on 7075 Al alloy in a silicate-based solution with Na2MoO4 additive using a unipolar waveform at constant current density. The coatings displayed micro-pores, micro-cracks, pancake-like and crater-like features, and also solidified molten oxide particles on the surface. The coatings were majorly composed of Al2O3 (γ, δ, and α), SiO2 (amorphous), and MoO3 phases, which confirms the incorporation of molybdenum in the case of additive-containing coatings. Molybdenum species were transported through cracks, channels, and micropores, as the ready access pathways into the coating and partly sealed the c…

Previsione delle prestazioni del veicolo su strada: stato dell’arte

2016

Questo lavoro contiene una rassegna dei metodi che sono usati per la previsione delle prestazioni del veicolo su strada, in dipendenza del motore installato. La prima parte mostra il calcolo delle resistenze al moto, cioè le forze che il veicolo deve vincere per avanzare sulle strade piane e in salita. Particolarmente interessante appare la parte che riguarda la resistenza aerodinamica, della quale si tratta di metodi sperimentali (galleria del vento), metodi empirici e metodi CFD. Si propone inoltre l’applicazione della norma CUNA sulla velocità per la determinazione dei consumi anche al calcolo dei coefficienti aerodinamici. La rassegna esclude la resistenza accidentale in curva perché no…

Engine/Transmission Matching

2014

This chapter deals with the forecasting of vehicle performance on the road, according to the installed engine. It begins with Section 1, which shows the calculation of the resistance to motion, that is, the forces that the vehicle must overcome to advance on flat roads and uphill. The calculation excludes accidental resistance in curves because it is not essential for predicting the behavior of the vehicle on the road. Section 2 begins with the power characteristic, the forecast by traction–speed and power–speed diagrams, calculation of gear ratios, and then passing to the limits to the estimated acceleration, feature consumption, and distance. This chapter concludes with a section on the d…