Search results for "electrical conductivity"
showing 10 items of 43 documents
Impact of freezing rate on electrical conductivity of produce
2013
The aim of this work was to compare the effects of freezing rate on electrical conductivity of potatoes, carrots and apples. Electrical conductivity tests were conducted on a custom ohmic cell while samples texture was measured by means of a universal testing machine. The raw un-pretreated samples were used as control. This study showed that freezing pre-treatments lead to differences in electrical conductivity of considered samples, producing structural damage, the latter being relatively more severe when the tested products undergo ohmic treatment.
Measurement of the intergranular corrosion growth kinetics on a 2024 aluminium alloy : new experimental approaches of damage as function of the envir…
2017
Costs of aeronautical maintenance can be reduced by implementation of “smart” inspection strategies integrating predictive data on the evolution of defects such as the propagation rate of intergranular corrosion.In this work, intergranular corrosion damage on 2024 aluminium alloy was characterized by two modes : the “perforating” damage (dissolution of the grain boundary tips) and the “blunting” damage (dissolution of the grain walls in the intergranular cavities). To evaluate the “perforating” damage, a new version of the TFP method (OTFP method) which is more complete, was designed. The OTFP method allows to detect all the intergranular corrosion defects and not only the fastest full pene…
High-Pressure Properties of Wolframite-Type ScNbO4
2022
In this work, we used Raman spectroscopic and optical absorption measurements and first-principles calculations to unravel the properties of wolframite-type ScNbO4 at ambient pressure and under high pressure. We found that monoclinic wolframite-type ScNbO4 is less compressible than most wolframites and that under high pressure it undergoes two phase transitions at ∼5 and ∼11 GPa, respectively. The first transition induces a 9% collapse of volume and a 1.5 eV decrease of the band gap energy, changing the direct band gap to an indirect one. According to calculations, pressure induces symmetry changes (P2/c–Pnna–P2/c). The structural sequence is validated by the agreement between phonon calcul…
Exploring the Simultaneous Effect of Total Ion Concentration and K:Ca:Mg Ratio of the Nutrient Solution on the Growth and Nutritional Value of Hydrop…
2022
Nutrient-efficient plants and agricultural systems could tackle issues resulting from conventional agriculture. Spiny chicory (Cichorium spinosum L.), a very adaptive, wild edible vegetable, is gaining commercial interest as a functional food. Floating-raft hydroponics is a method commonly used for the commercial cultivation of leafy vegetables due to numerous advantages compared to soil cultivation. In this paper, the simultaneous effects of different potassium, calcium and magnesium ratios and different electrical conductivity (EC) levels on the growth and mineral composition of hydroponically grown C. spinosum were investigated. Four nutrient solutions (NS) were compared, two NS with low…
Thermoelectrics: From history, a window to the future
2019
Thermoelectricity offers a sustainable path to recover and convert waste heat into readily available electric energy, and has been studied for more than two centuries. From the controversy between Galvani and Volta on the Animal Electricity, dating back to the end of the XVIII century and anticipating Seebeck’s observations, the understanding of the physical mechanisms evolved along with the development of the technology. In the XIX century Ørsted clarified some of the earliest observations of the thermoelectric phenomenon and proposed the first thermoelectric pile, while it was only after the studies on thermodynamics by Thomson, and Rayleigh’s suggestion to exploit the Seebeck effect for …
Comparative environmental analysis of soil sampling methods in precision agriculture for lime application in Paraná State, Brazil
2020
Precision agriculture (PA) provides techniques that favour the localized application of inputs allowing their rational use. This makes the PA a potential indicator of reduced operational costs, input volume, and environmental impacts. The objective of this study was to evaluate and compare the environmental effects of three different sampling methods used in PA for the lime application. The first sampling method evaluated was the grid sampling (GS). It was performed at a density of one sample per hectare in a 100×100 m georeferenced grid. The second method was the directed sampling, that was performed after defining the management zones by soil apparent electrical conductivity (ECa) using a…
Influence of organic material and sample parameters on the surface potential in Kelvin probe measurements
2019
Financial support provided by ERDF 1.1.1.1 activity project Nr. 1.1.1.1/16/A/046 “Application assessment of novel organic materials by prototyping of photonic devices” as well as Scientific Research Project for Students and Young Researchers Nr. SJZ2016/20 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged.
A NEW ROUTE TO OBTAIN PANI-EAA FLEXIBLE FILMS
2010
Influence of cultivation techniques and use of two nutritive solution with different electrical conductivity on the production and quality of cucumbe…
2009
The most suitable techniques and use of F1 hybrids enable greenhouse production to achieve high yields, with crops all year round. In Sicily, greenhouse production of cucumber is for fresh use (slicers), producing large fruit. The cultivation technique most suited to greenhouses is the vertical single stem. However, an innovative technique being proposed is of cultivation on a trellis, eliminating lower branches, and training the remaining branches upwards (vertical shoot positioning, VSP). Cucumbers in the south of Italy are grown as the main crop or as a catch crop between 2 main crops. The crop should be rotated on the same soil only after 3-4 years with another crop, unless the land is …