Search results for "Ingot"
showing 10 items of 26 documents
Récupération et recyclage sur la villa de Burgille (25) : l'exemple du plomb
2010
Temperature Dependent Suns-V<inf>oc</inf> of Multicrystalline Silicon Solar Cells from Different Ingot Positions
2018
This paper presents temperature dependent Suns- Voc measurements on multicrystalline silicon cells originating from different ingot positions. The effective lifetime is found to increase for all cells when the temperature is increased from 25°C to 6°C. However, cells from the top of the ingot show a considerably larger increas 40–50% for illumination conditions of 0.1-1 Sun, compared to an increase of 20-30% observed for cells from the bottom. The decrease in Voc with increasing temperature is found to be lower for cells from the top of the ingot compared to cells from the bottom. The temperature coefficient of the Voc is found to vary 5% along the ingot at 1 Sun, highlighting the influence…
Improving the material quality of silicon ingots by aluminum gettering during crystal growth
2016
We present a method for the purification of silicon ingots during the crystallization process that reduces significantly the width of the low charge carrier lifetime region at the ingot top. The back-diffusion of impurities from the ingot top is suppressed by adding a small amount of pure aluminum into the silicon melt right at the end of the solidification. We study the aluminum gettering effect by instrumental neutron activation analysis (INAA) and Fei imaging. Furthermore, we present a model for aluminum gettering of Fe in the silicon ingot that is in agreement with literature data for aluminum gettering at lower temperature. The distribution of iron in the ingots with and without alumin…
Verouudistuksen vaikutukset yritysten verosuunnitteluun
2004
Monelta kantilta : Ilkka Nummelalle omistettu juhlakirja
2010
First discovery of orichalcum ingots from the remains of a 6th century BC shipwreck near Gela (Sicily) seabed
2017
Ingots recently recovered from the seabed near Gela, a major harbour of Sicily, reveal an unexpected side of ancient metallurgy. The ingots were found near remains of a ship and earthenware dated around the end of the VI century BC and probably coming from the eastern Mediterranean and the Aegean sea. The ingots were analysed by means of X-Ray Fluorescence spectroscopy via a portable spectrometer. Results indicate that they are mostly consist of copper and zinc although many of them have a significant amount of lead. This alloy is nowday called brass, but in ancient time it was know as orichalcum, one of the rarest and most precious alloy along with gold and silver. Only small items of oric…
Kinetics of Photorefractive Light Scattering in LiNbO3:Cu and LiNbO3:Zn Single Crystals
2011
Results of studies of the kinetics of photorefractive light scattering (PRLS) in optically nonlinear congruent single crystals of lithium niobate (LiNbO3, Li/Nb = 0.946) containing multivalent cation admixtures of Cu [0.015 mass %] (“photorefractive”) and Zn [0.5 mass %] (“non-photorefractive”) are reported. The shape of the PRLS indicatrix is found to be different in case of Cu and Zn admixtures. However, the angular widening of the indicatrix in both cases reaches its stationary value faster at higher laser radiation intensities. The PRLS is found to depend on the site of the ingot from which the samples are cut – an evidence of non-uniform distribution of defects with localised electrons…
On the Control of the Secondary Cooling in the Continuous Casting Process
1987
Continuous casting is today replacing ingot casting as the major process for the production of steel in the form of slabs, blooms, billets etc. The complexity of this process is such that until recently innovations to machine design could only be tested by full scale runs on the production machine. This is extremely costly and in many cases production cannot be delayed for such tests to occur. For offering alternative means of testing new designs, numerical simulation models of the continuous casting process have been developed, especially during the last decade. We refer to conference proceedings [3], [5], [6] [16]. Furthermore we mention articles [4], [9], [13], [23], [24] concerning heat…
Experimental Investigation of the Optimal Ingot Resistivity for both the Cell Performances and the Temperature Coefficients for Different Cell Archit…
2018
Compensation engineering enables the achievement of lower ingot resistivities with relatively constant performances along the ingot height. In this paper the impact of the bulk resistivity on the cell performances and the temperature coefficients is investigated for compensated and non-compensated multicrystalline silicon. Based on experimental data we show that reducing the bulk resistivity below a certain value improves the temperature coefficients but deteriorates the cell performances for two distinct cell architectures (AI-BSF and PERCT). Moreover this performance loss is not balanced out by the improved temperature coefficient for operating conditions below 70°C.
A multivariate approach to the study of orichalcum ingots from the underwater Gela's archaeological site
2017
Abstract In this work a careful ICP-OES and ICP-MS investigation of 38 ancient ingots has been performed to determine both major components and trace elements content to find a correlation between the observed different features and the composition. The ingots, recovered in an underwater archaeological site of various finds near Gela (CL, Italy), were previously investigated by X-Ray Fluorescence (XRF) spectroscopy to know the composition of the alloy and it was found that the major elements were copper and zinc, in a ratio compatible with the famous orichalcum similar to the contemporary brass that was considered a precious metal in ancient times. The discovery of huge amount this alloy is…