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24.4: <i>Invited Paper:</i> The Breakthrough of large size electrical luminescence H‐Q LED TV, with 4K resolution and top emission device architecture, fabricated by ink jet printing technology
摘要： The domestic rainbow trout producers issued a standard with an aquatic association that classified rainbow trout as salmon, which raised the concern of consumers on the fish parasites infection. Herein, an in situ method was developed using "iKnife" and rapid evaporative ionization mass spectrometry based lipidomics for real-time discrimination of salmon and rainbow trout without sample preparation. A total of 12 fatty acids and 37 phospholipid species was identified and imported into statistical analysis for building an in situ and real-time recognition model. The ions with |p(corr)| > 0.5 and |p| > 0.03 were shown to be responsible for allocating samples, and the ions with high correlation values, such as of m/z 747.50, 771.49, and 863.55, indicated large weights in identification of the salmon and rainbow trout. The results indicated that this technology could be employed as a front-line test method to ensure the authenticity of salmon products.
关键词： real-time identification,rainbow trout,lipidomics,rapid evaporative ionization mass spectrometry,salmon
更新于2025-09-11 14:15:04
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - A Hyperspectral Camera Based on a Birefringent Ultrastable Common-Path Interferometer
摘要： Spectral imaging (or imaging spectroscopy) is a powerful technique that acquires the complete light spectrum at each point in the image of a scene. This can be obtained by a wide variety of methods. A first approach relies on placing band-pass spectral filters in front of a monochrome camera, thus acquiring the hyperspectral image at a limited number of spectral bands. A second class of techniques collects the whole continuous spectrum of each image point; an example is the combination of a dispersive spectrometer with a raster-scanning approach, at the cost of high losses imposed by the entrance slit of the spectrometer. An alternative approach combines imaging with Fourier-transform (FT) spectrometry [1]. This technique can retrieve in parallel the spectra for all pixels in a scene and is hence suited for imaging, but it requires controlling the delay with sub-cycle precision, which is very difficult to achieve with standard Michelson or Mach-Zehnder interferometers. Here we introduce a compact hyperspectral camera based on the FT approach, in which the interferometer is a version of the birefringent TWINS device [2, 3]; this inherently provides excellent robustness, accuracy and reproducibility thanks to its common-path geometry. Figure 1(a) shows the experimental setup. A and B are (cid:302)-BBO birefringent blocks with crossed optical axes; P1 polarizes the input light at 45° with respect to them. Block A is shaped in the form of two wedges, so that its thickness can be changed by translating a wedge with a motorized stage. During propagation, the ordinary and extraordinary light projections accumulate a relative delay ranging from positive to negative values according to the relative thickness of A and B. P2 projects the replicas to the same polarization (45°), enabling interference. The spectral resolution of the interferometer is inversely proportional to the user-adjustable total phase delay. The largest position scan of our interferometer introduces a delay of ±250 fs at (cid:540) = 600 nm, which corresponds to spectral resolution of 3 THz (~4 nm). Finally, a camera lens collects the light from the interferometer and creates an image of the object on an off-the-shelf 10-bits silicon monochrome CMOS camera. To characterize our innovative hyperspectral camera, we imaged the object shown in Fig. 1(b): it is made of four Spectralon color materials (green, blue, red, yellow, G, B, R, Y) acting as diffusive colorimetric standards with calibrated spectral reflectivity, and a white standard (W) with ~98.3% reflectivity in the 0.3-2.5(cid:541)m wavelength range. A 150-W Xenon lamp illuminated the object; on the test object we also sent the beams of a green (L1, (cid:540) = 532 nm) and a red (L2, (cid:540) = 635 nm) diode laser, employed to calibrate the frequency axis of the spectrometer and to provide its spectral resolution. The lens was set at the largest aperture; 400 delay-images were acquired with 25-ms integration time. The visibility of the interferograms is >84% for all pixels, demonstrating that our device fulfils the interferometric coherence required by the FT approach. Reflectance spectra retrieved from the measured interferograms, after white balance by weighting each curve by the W spectrum, are in excellent agreement with the calibrated ones (see spectra in Fig. 1(c)), demonstrating the very high spectral accuracy of our camera in the visible and near-infrared spectral range. The RGB image of panel (b) was generated from the collected hyperspectral image. In addition, we will show that the high sensitivity of the device allows measuring the weak emission from fluorescent samples.
关键词： Fourier-transform spectrometry,common-path interferometer,hyperspectral camera,birefringent
更新于2025-09-11 14:15:04
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Laser Spark Spectrometry Study of the Properties of Cotton Fabric Modified with Silver Nanoparticles and the Strength and Duration of the Antiseptic Effect
摘要： A laser spark spectrometry study was carried out on the effect of the silver content in cotton fabric on the extent and duration of the antiseptic effect. Durable antiseptic properties of various strength were found to appear only after tannide fixation of the composition in the fabric structure.
关键词： laser spark spectrometry,tannide fixation,cotton fabric,silver nanoparticles,antiseptic effect
更新于2025-09-11 14:15:04
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Rapid Diagnosis Of Drug Agglomeration And Crystallinity In Pharmaceutical Preparations By Electrospray Laser Desorption Ionization Mass Spectrometry Imaging
摘要： In this study we evaluate the applicability of electrospray laser desorption ionization mass spectrometry imaging (ELDI-MSI) to interrogate tablet formulations for the spatial distributions of ingredients. Tablet formulations with varying amounts of crystalline acetaminophen (the active pharmaceutical ingredient, API) were analyzed to determine if crystallinity could be evaluated via ELDI-MSI. ELDI-MSI concurrently imaged the API, binders, and surfactants. The spatial distributions of amorphous API were very similar to that of the surfactants and different from that of crystalline API. The higher the crystallinity in the tablet formulation, the more agglomeration of the active ingredient was observed by ELDI-MSI. This study shows the capability of ELDI-MSI to diagnose agglomeration and crystallinity content in pharmaceutical preparations with little to no sample preparation. The ability to concurrently image APIs with other components provides valuable information as to their form in the tablet.
关键词： ELDI,crystallinity,mass spectrometry imaging,pharmaceuticals,agglomeration
更新于2025-09-11 14:15:04
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Laser based analysis of transition metal boride thin films using liquid standards
摘要： In this work the use of two laser assisted direct solid sampling methods, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and laser induced breakdown spectroscopy (LIBS) for the determination of the stoichiometry of novel diboride based materials is reported. To overcome the need for certified reference materials or matrix matched standards, which were usually required for quantitative investigations with LA-ICP-MS or LIBS, in this work liquid standards are employed. For LA-ICP-MS the concept of self-aliquoting micro-grooves and for LIBS conventional dried droplets were used. As a model for application of the developed analytical procedures the ternary system W1-xTaxB2-z was used. Fabrication of W1-xTaxB2-z thin films with varying stoichiometry was performed via magnetron sputtering. Reference compositions were obtained by liquid digestion of the samples and subsequent ICP-OES measurement. Both laser-assisted methods enabled fast and spatially resolved measurements, although the LA-ICP-MS method generally yielded more accurate results. It was shown that the method can easily be adapted for the stoichiometry determination of systems with different elemental composition.
关键词： laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS),liquid calibration,Laser-induced breakdown spectroscopy (LIBS),borides,thin films
更新于2025-09-11 14:15:04
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Fast analysis of caffeinated beverages using laser diode thermal desorption mass spectrometry (LDTD-MS/MS)
摘要： A rapid method for quantitative caffeine analysis in carbonated and non-carbonated beverages and liquid dietary supplement products was developed based on the direct sample introduction technique of laser diode thermal desorption atmospheric pressure chemical ionisation with tandem mass spectrometry (LDTD-MS/MS). Product samples were diluted with a mixture of methanol, water, and d3-caffeine internal standard. Sample aliquots were filtered, spotted on a metal-lined LDTD microtitre plate, dried, and thermally desorbed for subsequent ionisation and analysis by MS/MS analysis. Each sample required a 6 s desorption, and sample-to-sample analysis time of less than 30 s per sample. Caffeine yielded a linear calibration curve over the range 0.5–100 μg mL?1 (R2 > 0.995). Caffeine recoveries from fortified samples ranged from 97% to 107% with <5% RSD. The caffeine determination was not affected by matrix interferences despite the large range of ingredients, vitamins, sweeteners, extracts, and additives present in the products tested, even though LDTD-MS/MS is a whole-sample desorption technique with no separation of matrix background. The method detection limit was below 0.12 μg mL?1. The method was applied to 33 caffeinated products and LDTD-MS/MS quantitative results closely correlated (R2 > 0.998) with the regulatory standard HPLC-UV method (AOAC Official Method 979.08).
关键词： quantitative analysis,direct analysis mass spectrometry,Caffeine,laser diode thermal desorption,energy drinks
更新于2025-09-11 14:15:04
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7.3: Research on LCD display performance improvement based on mini‐LED backlight
摘要： The changes of flavor components during boiling in Lentinus edodes were studied by high-performance liquid chromatography and gas chromatography-mass spectrometry in this article. Results showed that nonvolatile flavor components in L. edodes gradually transferred into the soup during boiling. Contents of nonvolatile flavor substances in the soup increased significantly (p < .05) compared with the preboiling period (15 minutes) and gradually maintained a balanced situation with the boiling time extended. During boiling, content of alcohols gradually reduced, especially the content of 1-octen-3-ol, which is a typical flavor component in L. edoedes. The contents of sulfur compounds, aldehydes, and hydrocarbons increased first and finally decreased gradually with the boiling time extended. Therefore, the changes of flavor components in the soup almost maintained a balanced situation with the boiling time from 30 to 60 minutes. The results of this article could provide a theoretical basis for the changes of flavor compounds in L. edodes during boiling.
关键词： flavor components,gas chromatography–mass spectrometry,High-performance liquid chromatography,boiling,Lentinus edodes
更新于2025-09-11 14:15:04
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Fe3O4-assisted laser desorption ionization mass spectrometry for typical metabolite analysis and localization: Influencing factors, mechanisms, and environmental applications
摘要： Fe3O4 has been suggested as an efficient matrix for small-molecule analysis by laser desorption ionization mass spectrometry (LDI-MS), but thus far there has been no systematic study exploring the influencing factors of nano-Fe3O4 on the detection of typical metabolites, or the mechanism by which nano-Fe3O4 assists the desorption and ionization of analytes after receiving laser energy. In this study, Fe3O4 nanoparticles with different physicochemical properties were synthesized and characterized. The results revealed that smaller particle size and greater surface hydroxyl amount of nano-spherical Fe3O4 could improve the intensity and relative standard deviation of typical metabolites by LDI-MS. The thermally driven desorption process played a vital role in LDI performance, but the chemical interactions between nano-Fe3O4 and analytes did not. Good intra- or inter-spot repeatability and linearity of analytes were obtained by the optimum Fe3O4-assisted LDI-MS. Finally, the developed method was successfully used for the rapid analysis and localization of endogenous metabolites in biofluids and whole zebrafish tissue section samples. Our results not only elucidate the influencing factors and mechanisms of nano-Fe3O4 for the detection of typical metabolites in LDI-MS but also reveal an innovative tool for the imaging of chemicals in the regions of interest in terms of eco-toxicological research.
关键词： time-of-flight mass spectrometry,physicochemical property,small-molecule metabolite,Fe3O4,laser desorption ionization
更新于2025-09-11 14:15:04
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Using Terahertz Spectrometry to Study the Thermal Decomposition of Energy Materials
摘要： This paper describes experimental results on using nonstationary spectrometry in a terahertz frequency range to determine the composition of gaseous products of decomposition of energy materials. Dependences of analytical signals on lines of the main products of ammonium nitrate and PETN decomposition on time are obtained.
关键词： terahertz spectrometry,energy materials,ammonium nitrate,PETN,thermal decomposition,decomposition kinetics,decomposition products
更新于2025-09-11 14:15:04
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A green single-tube sample preparation method for wear metal determination in lubricating oil by microwave induced plasma with optical emission spectrometry
摘要： A straightforward and rapid single-tube sample pretreatment for wear metals determination in used lubricating oils was developed in this work as an alternative to the reference pretreatment method (ASTM). A D-optimal mixture design on a three-component solution was performed. The optimal composition for the proposed sample preparation emulsion was 2 % v/v of xylene, 9.5 % v/v of Triton?X-114 and 88.5 % v/v of H2O. The determination of 18 wear metals was carried out by microwave induced plasma with optical emission spectrometer (MIP OES), and the results of the two sample preparations - conventional and proposed- were statistically compared. Also, a certified standard “wear metals in used lubricating oils” for pretreatment validation was used. The developed method was as effective as the reference method indicated by ATSM, similar in speed and simplicity, but superior from the environmental and economic point of view. The proposed pretreatment allowed Ag, Al, Ba, Ca, Cd, Cr, Cu, K, Mg, Mn, Mo, Ni, Pb, Si, Sn, Ti, V and Zn determination, with LOQ between 1.40 mg kg-1 for Ca and 6.34 mg kg-1 for Pb. The precisions established as the relative standard deviation (RSD) were better than 6.2%. The proposed method avoid sample handling, reducing contamination risks and analyte losses, affording significantly improvement on wear metal quantification.
关键词： Microwave induced plasma atomic emission spectrometry,Mixture experimental design,Wear metals,Green single-tube sample preparation,Used lubricating oils
更新于2025-09-11 14:15:04