Search results for "ingot"

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…

Reduced temperature sensitivity of multicrystalline silicon solar cells with low ingot resistivity

2016

This study presents experimental data on the reduction of temperature sensitivity of multicrystalline silicon solar cells made from low resistivity ingot. The temperature coefficients of solar cells produced from different ingot resistivities are compared, and the advantages of increasing the net doping are explained.

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…

Design of parallel compensator and stabilizing controller to mitigate non-minimum phase behaviour of the Czochralski Process

2020

Abstract This paper addresses the design of a parallel compensator and a stabilizing controller for the simplified crystal growth dynamics of the Czochralski (CZ) process, i.e., the process for the production of monocrystalline silicon ingots of uniform diameter. The diameter control of the produced ingots is achieved by a CCD camera measurement used to sense the radius of the boundary between the base of the growing crystal and the surrounding glowing meniscus — a raised melt surface connecting the crystal ingot with the flatter melt surface. Due to the intrinsic nature of the process, the bright ring radius measurement signal exhibits a non-minimum phase behaviour. A combination of the pa…

Newly discovered orichalcum ingots from Mediterranean sea: Further investigation

2021

Abstract In February 2016, 47 ingots were found in the seabed of Contrada Bulala (Gela, CL, Italy) near the site where 40 ingots had previously been recovered. The ingots composition was determined to be a Cu - Zn alloy, dated by the archaeologist to the VI century B.C. This specific alloy was then known as Orichalcum. From an archaeological point of view, the first question raised about the new discovery was whether the ingots of the first and the second excavations belonged to the same shipwreck. Following the previous study, an elemental analysis was performed on the ingots from the second finding by using ICP-OS and ICP-MS techniques. The chemometric treatment of the analytical results …

Récupération et recyclage sur la villa de Burgille (25) : l'exemple du plomb

2010

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…

Enhanced thermoelectric performance in the p-type half-Heusler (Ti/Zr/Hf)CoSb0.8Sn0.2 system via phase separation

2014

A novel approach for optimization of the thermoelectric properties of p-type Heusler compounds with a C1b structure was investigated. A successful recipe for achieving intrinsic phase separation in the n-type material based on the TiNiSn system is isoelectronic partial substitution of Ti with its heavier homologues Zr and Hf. We applied this concept to the p-type system MCoSb0.8Sn0.2 by a systematic investigation of samples with different compositions at the Ti position (M = Ti, Zr, Hf, Ti0.5Zr0.5, Zr0.5Hf0.5, and Ti0.5Hf0.5). We thus achieved an approximately 40% reduction of the thermal conductivity and a maximum figure of merit ZT of 0.9 at 700 °C. This is a 80% improvement in peak ZT fr…

S&P 500 -indeksin osinkoperusteinen arvonmääritys pitkällä aikavälillä

2017

Tässä Pro gradu –tutkielmassa selvitettiin, kuinka osinkoperusteinen arvonmääritys toimii S&P 500 indeksiin kuukausittaisella otannalla 1871 – 2016. Tämän lisäksi kartoitettiin, kuinka eri taloudelliset tekijät voivat selittää osaketuottoja. Samalla kartoitettiin miten muuttujien relaatiot ovat muuttuneet pitkällä aikavälillä. Tutkielmassa luotiin eri hintaestimaatteja, joilla pyrittiin arvioimaan tulevaisuuden osakehintaindeksin tasoja ja testattiin, kuinka hyvin estimaatit osuivat. Muuttujien relaatioita tutkittiin yhteisintegraatiotesteillä ja Granger –kausaalisuustesteillä, joiden perusteella voitiin päätellä, miten muuttujat ovat yhteydessä toisiinsa. Tämän lisäksi testattiin, onko pit…

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…