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oe1(光电查) - 科学论文

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出版时间
  • 2018
研究主题
  • electropolymerization
  • polyporphyrin films
  • quartz crystal microbalance method
  • oxygen electroreduction.
应用领域
  • Applied Chemistry
机构单位
  • G.A. Krestov Institute of Solution Chemistry of RAS
  • University Union Nicola Tesla
  • Ivanovo State University of Chemistry and Technology
61 条数据
?? 中文（中国） ▾

  • Target sequence recognition by a light-activatable bZIP factor, Photozipper

    摘要： Photozipper (PZ) is a light-activatable basic leucine zipper (bZIP) protein composed of a bZIP domain and a light-oxygen-voltage-sensing domain of aureochrome-1. Blue light induces dimerization and subsequently increases the affinity of PZ for the target DNA sequence. We prepared site-directed PZ mutants in which Asn131 (N131) in the basic region were substituted with Ala and Gln. N131 mutants showed spectroscopic and dimerization properties almost identical to wild-type PZ, as well as an increase of helical content in the presence of the target sequence. Quantitative analyses by electrophoretic mobility shift assay and quartz crystal microbalance (QCM) measurements demonstrated that the half-maximal effective concentrations of N131 mutants to bind to the target sequence were significantly higher than those of PZ. QCM data also revealed that N131 substitutions accelerated the dissociation speed without affecting the association speed, suggesting that a base-specific interaction of N131 occurred after the association between PZ and DNA. Activation of PZ by illumination decreased both the standard errors and the unstable period of QCM data. Optical control of transcription factors will provide new knowledge of the recognition of the target sequence.

    关键词： LOV,DNA-binding,Quartz crystal microbalance (QCM),aureochrome,bZIP

    更新于2025-09-23 15:21:01

  • Storage of RF photons in minimal conditions

    摘要： We investigate the minimal conditions to store coherently a RF pulse in a material medium. We choose a commercial quartz as a memory support because it is a widely available component with a high Q-factor. Pulse storage is obtained by varying dynamically the light–matter coupling with an analog switch. This parametric driving of the quartz dynamics can be alternatively interpreted as a stopped-light experiment. We obtain an ef?ciency of 26%, a storage time of 209 μs and a time-to-bandwidth product of 98 by optimizing the pulse temporal shape. The coherent character of the storage is demonstrated. Our goal is to connect different types of memories in the RF and optical domain for quantum information processing. Our motivation is essentially fundamental.

    关键词： quantum memory,quartz resonator,radiofrequency photons

    更新于2025-09-23 15:21:01

  • Crystallization processes of quartz in a granitic magma: Cathodoluminescence zonation pattern controlled by temperature and titanium diffusivity

    摘要： Quartz from a granitic pluton is found to have formed through sequential growth events under different mechanisms and crystallization temperatures, which can provide new insights into magmatic processes of granitic magmas that were eventually consolidified into plutons. The events were identified using 1) the description of crystal shape and occurrence, 2) the study of the internal structure with cathodoluminescence (CL), and 3) derivation of the crystallization temperatures based on TitaniQ thermometry. The magmatic quartz crystals from the Toki granite, central Japan, are characterized as having the following internal structures: oscillatory zonation, no-oscillatory zonation with luminescence gradation (gradational zonation), and heterogeneous CL. The quartz crystals with oscillatory zonation were formed in the temperature range of about 800 °C to below 700 °C, which is referred to as oscillatory zoning temperature (OZT) conditions. The CL zonation pattern was controlled by the temperature conditions and titanium diffusivity in the melt (magma). The crystallization process of quartz within the Toki granite reveals the cooling processes of the granitic pluton; the lithofacies with a high frequency of oscillatory-zoned quartz underwent slower cooling under the OZT conditions than those in other lithofacies.

    关键词： diffusion-controlled growth,Toki granitic pluton,Cathodoluminescence characterization,Oscillatory zonation,Quartz,TitaniQ thermometer

    更新于2025-09-23 15:19:57

  • Advantages and Limitations of Laser-Assisted Mass Spectrometry for the Local Determination of the Trace Element Composition of Fluid Inclusions in Quarzites in the Bural-Sardyk Deposit (Vostochny Sayan, Buryatia)

    摘要： The effect of laser radiation on the surface and volume of natural quartz of the Bural-Sardyk deposit (East Sayan, Buryatia) is studied. The influence of the main parameters of laser radiation with a wavelength of 213 nm (prefix NWR-213) and the properties of the sample on the results of elemental mass spectrometric analysis with inductively coupled plasma are established. The features of laser ablation of various microinclusions in quartz are considered. The main problems arising from the laser evaporation of fluid inclusions in quartzites for the quantitative determination of their chemical composition are indicated.

    关键词： superquartzite,fluid inclusions,LA-ICP-MS,inductively coupled plasma mass spectrometry,laser ablation,quartz

    更新于2025-09-23 15:19:57

  • One-Step Femtosecond Laser Stealth Dicing of Quartz

    摘要： We report on a one-step method for cutting 250-μm-thick quartz plates using highly focused ultrashort laser pulses with a duration of 200 fs and a wavelength of 1030 nm. We show that the repetition rate, the scan speed, the pulse overlap and the pulse energy directly influence the cutting process and quality. Therefore, a suitable choice of these parameters was necessary to get single-pass stealth dicing with neat and flat cut edges. The mechanism behind the stealth dicing process was ascribed to tensile stresses generated by the relaxation of the compressive stresses originated in the laser beam focal volume during irradiation in the bulk material. Such stresses produced micro-fractures whose controlled propagation along the laser beam path led to cutting of the samples.

    关键词： ultrashort laser pulses,stealth dicing,transparent materials,heat accumulation,quartz

    更新于2025-09-23 15:19:57

  • Immobilization of DNA on Quartz Crystal Microbalance Sensor Modified with Self-Assembled Monolayer of Thiol Derivative

    摘要： In this study, we investigated the direct detection of DNA, without pretreatment, using a quartz crystal microbalance (QCM) sensor. This sensor is modified by a self-assembled monolayer of a thiol derivative that has an amino group as the terminal functional group. Contact angle values and the attenuated total reflectance Fourier transform infrared (ATR/FT-IR) spectra of the QCM sensors after immersion into an ethanol solution of thiol derivatives clearly showed that self-assembled monolayers of the derivatives were formed on the QCM sensors. Although QCM measurements using unmodified and carboxylic group-modified sensors could not detect DNA-Na salt, the sensor modified with amino groups could detect the DNA. This system can be used for the analysis of the interaction between DNA and DNA-binding proteins.

    关键词： DNA,thiol derivative,quartz crystal microbalance,self-assembled monolayer

    更新于2025-09-23 15:19:57

  • Recycling of light-emitting diode waste quartz sand as a pozzolanic material

    摘要： LED waste quartz sand (LEDWS), which is a prominent byproduct of the LED manufacturing process, may contaminate the environment because it comprises numerous nanoparticles of SiO2, Al2O3, and SiC, which are hazardous ingredients that are harmful to the environment and human health when disposed of improperly. Therefore, this study investigated the pozzolanic reaction behavior of these industrial byproducts to obtain a valuable processing method for LEDWS in cement. The results showed that with increased curing time, the strength of the pastes that incorporated 10% LEDWS approached that of ordinary Portland cement. A stretching broad band was centered at 1074e1081 cm-1 from chemically bound H2O in the hydrated calcium silicate (CeSeH). Thus, the correlation between the hydration degree of the paste that incorporated LEDWS and compressive strength evolution is crucial. The results implied that LEDWS can be used as a partial replacement source for cement applications; thus, LEDWS can be used as pozzolanic material.

    关键词： Degree of hydration,Calcium silicate,Recycle,Light-emitting diode waste quartz sand,Pozzolanic reaction

    更新于2025-09-23 15:19:57

  • [IEEE 2018 IEEE 13th Annual International Conference on Nano/Micro Engineered and Molecular Systems (NEMS) - Singapore, Singapore (2018.4.22-2018.4.26)] 2018 IEEE 13th Annual International Conference on Nano/Micro Engineered and Molecular Systems (NEMS) - A Miniature System for Classification and Concentration Detection of PM Based on 3D Printed Virtual Impactor and QCM Sensor

    摘要： In this paper, we report a miniature system for separation and concentration detection of airborne particulate matter (PM) based on three-dimensional (3D) printed virtual impactor and quartz crystal microbalance (QCM) sensor. The virtual impactor is optimized by computational fluid dynamics (CFD) simulation to have a relatively small size of 24 × 24 × 10 mm3. The performance of the miniature PM monitoring system is characterized through classification and detection of silicon oxide powers with diameter ranging from 0.5 to 10 μm in a chamber. The experimental results show that particles smaller than cutoff diameter of 2.5 μm are separated by the virtual impactor according to their size and detected by the QCM sensor. Moreover, the resonant frequency of the QCM sensor shows a linear decrease with the increment of PM mass loading.

    关键词： Particulate matter,Virtual impactor,Quartz crystal microbalance,Classification

    更新于2025-09-19 17:15:36

  • Microchannel Fabrication in Fused Quartz by Backside Laser-Induced Plasma Ablation Using 248 nm KrF Excimer Laser

    摘要： Laser-induced plasma ablation (LIPA) using a 248 nm KrF excimer laser was investigated for microchannel fabrication. Examination of the morphology in relation to ablation performance was emphasized, and a synthetic LIPA mechanism model was proposed based on the results. Backside LIPA with a metal target on the bottom can be attributed to a combination of two phenomena: laser-induced plasma vaporization thermal ablation from the metal target below and enhanced laser–glass direct interaction from the plasma residuum. The laser absorption enhancement of quartz substrate resulting from the metal residuum was validated clearly using absorption spectrum measurements. The influence of laser parameters on the etching quality during LIPA was also analyzed for processing optimization. Finally, fused quartz glass microchannels of outstanding surface quality and dimension uniformity were implemented. The channel depth was 28 μm, and the bottom surface roughness was better than several hundred nanometers.

    关键词： excimer laser,plasma,fused quartz glass,laser ablation,microstructure

    更新于2025-09-16 10:30:52

  • A novel quartz-crystal microbalance humidity sensor based on solution-processible indium oxide quantum dots

    摘要： Having a large surface area, like the quantum con?nement e?ect also caused by the nano-level size of quantum dots (QDs), creates fantastic potential for humidity sensing. A high concentration of surface adsorption sites initiates an increased response. Porosity between QDs allows fast water vapor penetration and out?ow. Here, a quartz-crystal microbalance (QCM) humidity sensor was prepared using indium oxide (In2O3) QDs, synthesized via a solvothermal method. After the In2O3 QDs were directly spin-coated onto the QCM, an annealing process removed organic long chains and exposed more moisture adsorption sites on the surfaces of the QDs. The annealed QCM humidity sensor exhibited high sensitivity (56.3 Hz per %RH at 86.3% RH), with a fast response/recovery time (14 s/16 s). Long carbon chains were broken down, and hydrogen-bonded hydroxyl groups were chemisorbed to the QDs. The chemical reaction was reduced by these chemisorbed hydrogen-bonded hydroxyl groups. Mass change was mostly caused by fast multilayer physisorption. Thus, the transducer can e?ectively and precisely monitor the moisture from a person's breath. In2O3 QD-modi?ed QCM sensors demonstrate promising humidity-sensing applications in daily life.

    关键词： indium oxide quantum dots,annealing process,solvothermal method,humidity sensor,quartz-crystal microbalance

    更新于2025-09-16 10:30:52