Search results for " resolution"
showing 10 items of 1159 documents
Photoluminescence-Based Spatially Resolved Temperature Coefficient Maps of Silicon Wafers and Solar Cells
2020
In this article, we present a method to obtain implied open-circuit voltage images of silicon wafers and cells at different temperatures. The proposed method is then demonstrated by investigating the temperature coefficients of various regions across multicrystalline silicon wafers and cells from different heights of two bricks with different dislocation densities. Interestingly, both low and high temperature coefficients are found in dislocated regions on the wafers. A large spread of temperature coefficient is observed at regions with similar performance at 298 K. Reduced temperature sensitivity is found to be correlated with the increasing brick height and is exhibited by both wafers and…
Choice of the detectors for light impurities plasma studies at W7-X using ‘CO Monitor’ system
2019
Abstarct The ‘CO Monitor’ is a new spectrometer system dedicated for the continuous measurements of line intensities of carbon, oxygen, boron and nitrogen at the fusion plasma experiment Wendelstein 7-X (W7-X). Its main purpose is to deliver constant information about indicated elements with high time resolution (better than 1 ms), but low spatial resolution since the line shapes are not going to be investigated. The system consists of four independent channels, each equipped with dispersive element dedicated for measurement of selected line of interest. In order to perform the highest efficiency of the ‘CO Monitor’ system, it is essential to choose the proper detector type for this task. T…
High spatial resolution strain measurements at the surface of duplex stainless steels
2007
International audience; The determination of local strain fields at the surface of materials is of major importance for understanding their reactivity. In the present paper, lithography is used to fabricate grid points at the microscale and to map strain gradients within grains and between grains. This method was applied to duplex stainless steels which exhibit heterogeneous strain distributions under straining conditions. The influence of various parameters (the specimen microstructure, the density of slip bands, the number of systems activated and the grid geometry) on the strain value was discussed.
Color centers in diamond as novel probes of superconductivity
2018
Magnetic imaging using color centers in diamond through both scanning and wide-field methods offers a combination of unique capabilities for studying superconductivity, for example, enabling accurate vector magnetometry at high temperature or high pressure, with spatial resolution down to the nanometer scale. The paper briefly reviews various experimental modalities in this rapidly developing nascent field and provides an outlook towards possible future directions.
Broadband Ultrahigh-Resolution Spectroscopy of Particle-Induced X Rays: Extending the Limits of Nondestructive Analysis
2016
Nondestructive analysis (NDA) based on x-ray emission is widely used, for example, in the semiconductor and concrete industries. Here, we demonstrate significant quantitative and qualitative improvements in broadband x-ray NDA by combining particle-induced emission with detection based on superconducting microcalorimeter arrays. We show that the technique offers great promise in the elemental analysis of thin-film and bulk samples, especially in the difficult cases where tens of different elements with nearly overlapping emission lines have to be identified down to trace concentrations. We demonstrate the efficiency and resolving capabilities by spectroscopy of several complex multielement …
Evaluation of the Colorimetric Performance of Single-Sensor Image Acquisition Systems Employing Colour and Multispectral Filter Array
2015
International audience; Single-sensor colour imaging systems mostly employ a colour filter array (CFA). This enables the acquisition of a colour image by a single sensor at one exposure at the cost of reduced spatial resolution. The idea of CFA fit itself well with multispectral purposes by incorporating more than three types of filters into the array which results in multispectral filter array (MSFA). In comparison with a CFA, an MSFA trades spatial resolution for spectral resolution. A simulation was performed to evaluate the colorimetric performance of such CFA/MSFA imaging systems and investigate the trade-off between spatial resolution and spectral resolution by comparing CFA and MSFA …
High-Resolution Stimulated Raman Spectroscopy and Analysis of the ν1 Stretching Band of GeD4
2007
The high-resolution stimulated Raman spectrum of the ν1 band of GeD4 with natural isotopic abundance germanium has been recorded. It has been analyzed as part of the ν1/ν3 stretching dyad. The ν1 and ν3 band centers have been deduced for all the isotopologues. Copyright © 2006 John Wiley & Sons, Ltd.
Asymmetric Synthesis of Spiro β-Lactamsviaa Squaramide- Catalyzed Sulfa-Michael Addition/Desymmetrization Protocol
2016
An efficient asymmetric synthesis of spirocyclohexenone β-lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide-catalyzed sulfa-Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5-cyclohexadienones.
Organocatalytic Oxidation of Secondary Alcohols Using 1,2-Di(1-naphthyl)-1,2-ethanediamine (NEDA)
2014
Diamine, 1,2-di(1-naphthyl)-1,2-ethanediamine (NEDA), efficiently catalyzes the oxidation of alcohols by using TBHP as an oxidant. Notably, secondary benzyl alcohols are oxidized in almost quantitative yields, and the catalyst also displays high activity towards even hindered cycloaliphatic secondary alcohols. With enantiopure (R,R)-NEDA, oxidative kinetic resolution can be realized and depending on the alcohol ee up to 99 % are achieved.
Analysis of psychoactive substances in water by information dependent acquisition on a hybrid quadrupole time-of-flight mass spectrometer.
2016
Emerging drugs of abuse, belonging to many different chemical classes, are attracting users with promises of “legal” highs and easy access via internet. Prevalence of their consumption and abuse through wastewater-based epidemiology can only be realized if a suitable analytical screening procedure exists to detect and quantify them in water. Solid-phase extraction and ultra-high performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UHPLC–QqTOF–MS/MS) was applied for rapid suspect screening as well as for the quantitative determination of 42 illicit drugs and metabolites in water. Using this platform, we were able to identify amphetamines, tryptamines, piperazines, p…