- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Detection of Tetracycline in Water Using Glutathione-protected Fluorescent Gold Nanoclusters
摘要： Tetracycline (Tc), a widely used antibiotic, is one of the major pollutants in water. Herein, glutathione (GSH)-protected Au nanoclusters (GSH-AuNCs) were prepared to detect Tc. The fluorescence quenching ratio of GSH-AuNCs shows an excellent linear response against tetracycline in the concentration range of 50 μg/L – 50 mg/L with the detection limit of 5.31 μg/L. For the test paper prepared by GSH-AuNCs, 1 mg/L Tc caused a significant difference that could be recognized by the naked eye. The method exhibited good selectivity and excellent recovery when applied to a tap water sample. The method has the potential for Tc detection in real samples.
关键词： tetracycline detection,Au nanocluster,glutathione,recovery experiment,quenching ratio
更新于2025-11-19 16:56:35
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Facile synthesis of yellow emissive carbon dots with high quantum yield and their application in construction of fluorescence-labeled shape memory nanocomposite
摘要： Synthesizing carbon dots (CDs) with efficient long-wavelength emissions (i.e., yellow- to red light) generally suffer from sophisticated approaches, time-consuming process, harsh conditions, and requirement of organic solvent; also, a further limitation of the resulting CDs is relatively low quantum yield (QY) in aqueous solution. Herein, novel yellow emitting CDs (Y-CDs) with a considerable QY of 62.8% were synthesized from a precursor comprising resorcinol and o-phenylenediamine via a facile microwave method. To probe the fluorescence mechanism, another typical resorcinol-derived CDs using ethylenediamine as dopant were fabricated as well, showing strong green emission with an absolute QY of 60.6%. Spectroscopic and structural characterizations indicated that the distinct redshift of green to yellow emission depended on the dimension of conjugated sp2-domain and the content of graphitic N heavily, while the excellent QY was highly related to the low proportion of defective sp2 carbon cluster and high nitrogen content within CDs. Moreover, the Y-CDs were confirmed to be capable of introducing additional crosslinking points in poly(vinyl alcohol) (PVA) polymer, which resulted in the Y-CDs-contained nanocomposite behaving superior and tunable water-induced shape recovery performances. Importantly, since being labeled with long-wavelength emission, the responsiveness of PVA/Y-CDs composite will contribute to its versatile utilization in biology-relevant fields.
关键词： shape recovery,fluorescence mechanism,yellow emission,carbon dots,nanocomposite
更新于2025-11-14 15:23:50
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Tannic acid-derivatized graphitic carbon nitride quantum dots as an “on-off-on” fluorescent nanoprobe for ascorbic acid via copper(II) mediation
摘要： A microwave-assisted hydrothermal route was employed to prepare fluorescent tannic acid (TA)-derivatized graphitic carbon nitride quantum dots. The resulting dots display blue fluorescence (best measured at excitation/emission wavelengths of 350/452 nm) with a quantum yield as high as ~44%. The incorporated TA imparts a fluorescence switching behavior in that very low concentrations of Cu(II) can quench the fluorescence, while (AA) can restore it. It is presumed that AA causes Cu(II) to be transformed to Cu(I). Based on these findings, a fluorometric method was designed for AA detection. The probe allows AA to be detected with a 50 pM limit of detection and a linear analytical range that extends from 0.1 to 200 nM of AA. Real and spiked samples were successfully assayed by the probe to demonstrate its analytical applicability.
关键词： Fluorescence recovery,Metal ions,Graphitic nanosheets,Biomolecules,Polyphenolic compounds,Optical probe,Quantum dots
更新于2025-10-22 19:40:53
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[IEEE 2018 Chinese Control And Decision Conference (CCDC) - Shenyang (2018.6.9-2018.6.11)] 2018 Chinese Control And Decision Conference (CCDC) - Optic disc segmentation method based on low rank matrix recovery theory
摘要： Optic disc(OD) detection and segmentation is one of the key elements for automatic retinal disease screening systems. This paper proposes an optic disc segmentation algorithm. The unified method based on low rank matrix recovery theory is used to make a significant detection. Then Hough transform is combined to obtain the final segmentation results. The proposed algorithm has short computation time and low complexity. It is robust to variable image illuminations and angles. The algorithm achieves the OD segmentation accuracy of 92.9% of the images on the MESSIDOR public dataset.
关键词： Optic disc,Hough transform,Segmentation,Low rank matrix recovery
更新于2025-09-23 15:23:52
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Solar Heterogeneous Photocatalytic Oxidation for Water and Wastewater Treatment: Problems and Challenges
摘要： Solar operation of heterogeneous photocatalytic oxidation reactors is looked at as a sustainable process for water and wastewater treatment, because it does not consume electric power and chemicals. However, there are still problems for technical-scale application. The problems addressed in this article are large area demand, water evaporation from open reactors and lack of simple photocatalyst recovery. An optimum solar reactor type is the parabolic compound collector reactor with borosilicate glass tubes. Challenges for further research are improvement in mass transfer as well as identification of novel photocatalysts which make use also of visible light, are efficient and stable, and are easy to be produced in an economically feasible way. Also the combination of photocatalysts with adsorbents is promising. Although membrane filtration processes have been successfully combined with solar photocatalytic oxidation and represent a safe barrier against spreading photocatalyst nanoparticles into the aquatic environment, more simple and less energy-consuming methods for photocatalyst recovery would be desirable.
关键词： Photocatalyst recovery,Novel photocatalysts,Solar photocatalytic oxidation,Photocatalysis adsorption hybrid process,Mass transfer
更新于2025-09-23 15:23:52
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Enhanced sensor life using UV treatment of sulphur poisoned Pt-PtOx
摘要： In this work, we report a novel method for recovery of sulphur poisoned platinum/platinum oxide (Pt-PtOx) core-shell nanowire sensor using UV irradiation. The optimum core to shell thickness ratio and the operating conditions are the key factors to achieve a high-performance H2S sensor, described in this report. The fabricated core-shell nanowire sensor demonstrated response of 6.4% at 1 ppm H2S with detection limit of 10 ppb at 150°C operating temperature. The sensor undergoes prominent time-dependent poisoning at H2S exposure of 3 ppm when operated at 150°C due to sensor surface contamination by sulphur, later confirmed by XPS analysis. Ultraviolet light at two wavelengths, 365 nm, and 248 nm is investigated to recover the poisoned Pt-PtOx surface. UV irradiation at 248 nm for 5 minutes results in sensor recovery, confirmed by further H2S sensing characterization and XPS studies on the recovered sensor. To the best of our knowledge, this is one of the first reports on UV irradiation for recovery of sulphur poisoned metal-oxide surfaces.
关键词： sulphidation,recovery,plasma oxidation,UV irradiation,core-shell nanowire
更新于2025-09-23 15:23:52
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A 200 Mb/s～3.2 Gb/s referenceless clock and data recovery circuit with bidirectional frequency detector
摘要： This paper presents a 200-Mb/s to 3.2-Gb/s half-rate referenceless clock and data recovery (CDR) circuit in 180 nm CMOS process. A bidirectional frequency detector (FD) is proposed to eliminate the harmonic locking and reduce the frequency acquisition time. A frequency band selector for wide-range the voltage-control oscillator (VCO) is also presented to select an exact frequency band of the VCO. The simulation shows the CDR achieves 11-ps peak-to-peak jitter at 3 Gb/s and the frequency acquisition time of 11.8 μs.
关键词： wide-band VCO,bidirectional frequency detector,referenceless,clock and data recovery
更新于2025-09-23 15:23:52
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Spatial carrier phase shifting method for the phase recovery from two interferograms with closed fringes
摘要： A procedure is developed to recover the phase from two interferograms with a non-constant phase shift between them. This method may find broad applications when environmental disturbances do not allow implementing traditional phase shifting techniques which normally require three or more images. A spatial carrier phase shifting method is implemented to analyze the two measured temporal phase shifted interferometric images. This approach is very fast, avoids the use of fringe normalization techniques, preserves good tolerance against small (λ/20) or non-constant phase shifts, background and modulation variations and noise as tested in real and simulated data.
关键词： spatial carrier,interferogram evaluation,phase shifting,Fringe analysis,phase recovery
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE Industry Applications Society Annual Meeting (IAS2018) - Portland, OR (2018.9.23-2018.9.27)] 2018 IEEE Industry Applications Society Annual Meeting (IAS) - Neural Network Based Irradiance Mapping Model of Solar PV Power Forecasting Using Sky Image
摘要： Indirect seismic economic loss not only impacts regional economic recovery policies but is also related to economic assistance at the national level. Due to cross-regional economic activities and the difficulty of obtaining data, it is difficult for the indirect economic loss survey to cover all economic activities. However, nighttime light in an area can reflect the economic activity of the region. This article focuses on the indirect economic losses caused by the 2008 Wenchuan earthquake and evaluation of the progress of restoration and reconstruction based on nighttime light images. First, the functional relationship between GDP and nighttime light parameters is established based on pre-earthquake data. Next, the indirect loss of the earthquake is evaluated by the nighttime light attenuation in the disaster area after the earthquake. Then, the capacity recovery, which is characterized by the brightness recovery process of the light area, is evaluated. Lastly, the process of light expansion in the disaster area is analyzed to evaluate the speed and efficiency of economic expansion.
关键词： economic recovery,Wenchuan earthquake,economic expansion,nighttime light images,Indirect seismic economic loss
更新于2025-09-23 15:23:52
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A 15-Gb/s Sub-Baud-Rate Digital CDR
摘要： This paper presents a sub-baud-rate clock and data recovery (CDR) circuit that can recover clock and data using only differential quarter-rate clocks. A combination of eight samplers and an integrator recover four data bits in each clock cycle. Four of the eight samplers are re-used for phase detection as well as for background calibration to improve the robustness of the CDR to process, voltage, and temperature variations. A continuous-time linear equalizer is used to compensate for inter-symbol interference up to 11 dB. The CDR prototype fabricated in a 65-nm CMOS recovers 15.2-Gb/s data using only differential 3.8-GHz clock and achieves bit error rate (BER) < 10?12, >10-MHz jitter tolerance (JTOL) corner, and 548 fsrms recovered clock jitter. The total power consumption is 29 mW, which translates to an energy efficiency of 1.9 pJ/bit.
关键词： clock and data recovery (CDR),Baud-rate,phase detector,digital CDR,integrator,sub-baud-rate
更新于2025-09-23 15:23:52