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Light(Science & Applications) 2024年第6期13卷 1008-1011页

作者： markus suta Inorganic Photoactive Materials Faculty of Mathematics and Natural SciencesHeinrich Heine University DusseldorfDusseldorfGermany

An ultra-simple and miniaturized spectrometer using an arbitrarily shaped pinhole as diffraction element reconstructs a broadband spectrum from the information of diffraction of monochromatic radiation by clever computational reconstruction *** circumvents complex calibration procedures and paves the way to cost-effective on-chip spectrometers combining fast acquisition without significant loss in spectral resolution.

关键词： arbitrarily shaped element

Extending the dynamic temperature range of Boltzmann thermometers

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Light(Science & Applications) 2022年第12期11卷 3069-3079页

作者： Thomas Pieter van Swieten Jesse Merlijin Steenhoff Auke Vlasblom Ravi de Berg Sam Pieter Mattern Freddy Teunis Rabouw markus suta Andries Meijerink Debye Institute for Nanomaterials Science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands Inorganic Photoactive Materials Heinrich Heine University DüsseldorfUniversitätsstraBe 140225 DüsseldorfGermany

Lanthanide-doped(nano)crystals are an important class of materials in luminescence *** working mechanism of these thermometers is diverse but most often relies on variation of the ratio of emission intensities from two thermally coupled excited states with *** low temperatures,nonradiative coupling between the states can be slow compared to radiative decay,but,at higher temperatures,the two states reach thermal equilibrium due to faster nonradiative *** thermal equilibrium,the intensity ratio follows Boltzmann statistics,which gives a convenient model to calibrate the ***,we investigate multiple strategies to shift the onset of thermal equilibrium to lower temperatures,which enables Boltzmann thermometry in a wider dynamic *** use Eu^(3+)-doped microcrystals as a model system and find that the nonradiative coupling rates increase for host lattices with higher vibrational energies and shorter lanthanide-ligand distances,which reduces the onset temperature of thermal equilibrium by more than 400 *** additionally reveal that thermometers with excited states coupled by electricdipole transitions have lower onset temperatures than those with magnetic-dipole-coupled states due to selection *** insights provide essential guidelines for the optimization of Boltzmann thermometers to operate in an extended temperature range.

关键词： equilibrium excited dynamic

One ion to catch them all: Targeted high-precision Boltzmann thermometry over a wide temperature range with Gd^(3+)

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Light(Science & Applications) 2021年第12期10卷 2443-2454页

作者： Dechao Yu Huaiyong Li Dawei Zhang Qinyuan Zhang Andries Meijerink markus suta Engineering Research Center of Optical Instrument and System The Ministry of EducationShanghai Key Laboratory of Modern Optical SystemsUniversity of Shanghai for Science and TechnologyShanghai 200093China Condensed Matter and Interfaces Debye Institute for Nanomaterials ScienceDepartment of ChemistryUtrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China State Key Laboratory of Luminescent Materials and Devices and Institute of Optical Communication MaterialsSouth China University of TechnologyGuangzhou 510641China Inorganic Photoactive Materials Institute of Inorganic ChemistryHeinrich Heine University DüsseldorfUniversitätsstraße 140225 DüsseldorfGermany

Ratiometric luminescence thermometry with trivalent lanthanide ions and their 4f^(n) energy levels is an emerging technique for non-invasive remote temperature sensing with high spatial and temporal *** ratiometric luminescence thermometry often relies on thermal coupling between two closely lying energy levels governed by Boltzmann’s *** its simplicity,Boltzmann thermometry with two excited levels allows precise temperature sensing,but only within a limited temperature *** low temperatures slow down the nonradiative transitions required to generate a measurable population in the higher excitation level,temperatures that are too high favour equalized populations of the two excited levels,at the expense of low relative thermal *** this work,we extend the concept of Boltzmann thermometry to more than two excited levels and provide quantitative guidelines that link the choice of energy gaps between multiple excited states to the performance in different temperature *** this approach,it is possible to retain the high relative sensitivity and precision of the temperature measurement over a wide temperature range within the same *** demonstrate this concept using YAl_(3)(BO_(3))_(4)(YAB):Pr^(3+),Gd^(3+)with an excited 6 PJ crystal field and spin-orbit split levels of Gd^(3+)in the UV range to avoid a thermal black body background even at the highest *** phosphor is easily excitable with inexpensive and powerful blue LEDs at 450 ***-background luminescence thermometry is realized by using blue-to-UV energy transfer upconversion with the Pr^(3+)−Gd^(3+)couple upon excitation in the visible *** method allows us to cover a temperature window between 30 and 800 K.

关键词： excited excitation luminescence

Diagnosis of Sugarcane White Leaf Disease Using the Highly Sensitive DNA Based Voltammetric Electrochemical Determination

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American Journal of Plant Sciences 2014年第15期5卷 2256-2268页

作者： Porntip Wongkaew suta Poosittisak Department of Chemistry Faculty of Science Khon Kaen University Khon Kaen Thailand Plant Pathology Division Faculty of Agriculture Khon Kaen University Khon Kaen Thailand

A simple and highly sensitive analysis by electrochemical voltammetry has been developed for diagnosis of the most destructive crop disease in Thailand known as sugarcane white leaf (SCWL). Determination of the corresponding DNA interaction has been obtained from the voltammetric signals of electroactive redox methylene blue (MB) by means of cyclic and differential pulse voltammetry. In this study, a chitosan-modified glassy carbon electrode (GCE) was created by self-assembly to produce electrostatic platform for effective immobilization of the DNA. Fabrication of SCWL-DNA hybridization detection system was performed by immobilizing the ssDNA probe as a specific sensor onto chitosan-modified GCE. Hybridization of complementary DNA from the real samples could then be detected by its respective MB signal. This fabricated DNA probe sensor was shown to be capable for discriminative identification among the DNAs from SCWL plants, mosaic virus infected sugarcane and healthy sugarcane plants. Relationship between the specific hybridization signal and DNA target concentration was also observed under optimal condition. The detection limit of 4.709 ng/μl with the regression coefficient (R2) of 0.998 and overall RSD of 2.44% were obtained by response curve fit analysis. The actual SCWL-ssDNA immobilization and hybridizing event were subsequently confirmed by an observation under atomic force microscope. Thus these experiments demonstrate the first successful and effective DNA based voltammetric electrochemical determination for a verification of the specific pathogenic infection within plants from the real epidemic field.

关键词： Sugarcane White Leaf Disease Chitosan-Modified Glassy Carbon Electrode DNA Hybridization Sensor Methylene Blue Voltammetric Signal Atomic Force Microscope