Concept design of a UV light-emitting diode based fluorescence sensor for real-time bioparticle detection

AbstractA device for measuring the flow, duration and volume characteristics of human puffing behaviour when smoking cigarettes is described. Cigarettes are smoked through a holder comprising a measured pressure drop across a critical orifice. The holder also contains a Light Emitting Diode (LED) and photodetector that measures light obscuration in order to estimate nicotine-free dry particulate matter (NFDPM, “tar”) delivery. All data are recorded on a puff-by-puff basis and displayed in real time. These NFDPM estimates are known as optical “tar” (OT), and are derived from the calibration of the OT measurement versus gravimetric NFDPM yields of cigarettes under a range of smoking regimes. In a test study, puff volumes from 20-80 mL were recorded to ± 6.0% of a pre-set volume, with an absolute error of 4.7 mL for an 80 mL volume drawn on a lit cigarette, and an average error of less than 2.0 mL across the range 20-80 mL. The relationship between NFDPM and OT was linear (R2 = 0.99) and accurate to ± 1.3 mg per cigarette over the range 1-23 mg per cigarette. The device provides an alternative to the widely used part filter methodology for estimating mouth level exposure with an added benefit that no further laboratory smoking replication or analysis is required. When used in conjunction with the part filter methodology, the puffing behaviour recorded can explain anomalies in the data while providing a second independent estimate.

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Suppression of “volcano” morphology and parasitic defect luminescence in AlGaN-based deep-UV light-emitting diode epitaxy

Results in Physics ◽

10.1016/j.rinp.2019.102285 ◽

2019 ◽

Vol 13 ◽

pp. 102285 ◽

Cited By ~ 1

Author(s):

Chia-Yen Huang ◽

Tsung-Yen Liu ◽

Shih-Ming Huang ◽

Kai-Hsiang Chang ◽

Tsu-Ying Tai ◽

...

Keyword(s):

Uv Light ◽

Light Emitting Diode ◽

Light Emitting ◽

Deep Uv ◽

Defect Luminescence

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Chromaticity Study of Curcumin Dye Extracted from Curcuma longa L. Using for UV Light down Conversion for White Light Emitting Diode

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.290.183 ◽

2019 ◽

Vol 290 ◽

pp. 183-189

Author(s):

Mahmood Al Shafouri ◽

Naser Mahmoud Ahmed ◽

Zainuriah Hassan ◽

Munirah Abdullah Almessiere

Keyword(s):

White Light ◽

Uv Light ◽

Light Emitting Diode ◽

Curcuma Longa ◽

Color Temperature ◽

Light Emitting ◽

Chromaticity Coordinates ◽

Major Factors ◽

Color Rendering ◽

Down Conversion

In thus study, Turmeric phosphor dye was extracted from Curcuma Longa L. via a simple technique using silica gel. The phosphor was used for light down-conversion of UV light for the manufacture white light emitting diode (WLED). The UV-LED was analyzed over 395nm wavelengths. The characteristics of the white light chromaticity were controlled by tuning the current and phosphor concentration. An optimum color rendering index (CRI) value of 63.4 was obtained. The chromaticity coordinates (CIE) and correlated color temperature (CCT) were measured for various currents and phosphor concentrations. The white phosphor exhibited CIE value of 0.355,0.338 and CCT of 4567 K. The concentration of phosphor and amount of applied current were confirmed to be major factors that control the intensity of white light emitted from the sample, where CIE and CRI of the emitted light steadily increased with the concentration of phosphor and current. Thus, phosphor concentration has a critical effect on conversion efficiency. Key words: Turmeric, phosphor, WLED, curcumin

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High Sensitivity of NO Gas Sensors Based on Novel Ag-Doped ZnO Nanoflowers Enhanced with a UV Light-Emitting Diode

ACS Omega ◽

10.1021/acsomega.8b01882 ◽

2018 ◽

Vol 3 (10) ◽

pp. 13798-13807 ◽

Cited By ~ 17

Author(s):

You-Ting Tsai ◽

Shoou-Jinn Chang ◽

Liang-Wen Ji ◽

Yu-Jen Hsiao ◽

I-Tseng Tang ◽

...

Keyword(s):

Gas Sensors ◽

Uv Light ◽

Light Emitting Diode ◽

High Sensitivity ◽

Light Emitting ◽

Doped Zno

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Visible-Light-Driven Photocatalytic Activity of Magnetic BiOBr/SrFe12O19 Nanosheets

Nanomaterials ◽

10.3390/nano9050735 ◽

2019 ◽

Vol 9 (5) ◽

pp. 735 ◽

Cited By ~ 3

Author(s):

Taiping Xie ◽

Jiao Hu ◽

Jun Yang ◽

Chenglun Liu ◽

Longjun Xu ◽

...

Keyword(s):

Magnetic Properties ◽

Electron Microscope ◽

Visible Light ◽

Uv Light ◽

Light Emitting Diode ◽

Active Species ◽

Composite Catalyst ◽

Light Emitting ◽

Transmission Electron ◽

Visible Light Driven

Magnetic BiOBr/SrFe12O19 nanosheets were successfully synthesized using the hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and UV-visible diffused reflectance spectra (UV-DRS), and the magnetic properties were tested using a vibration sample magnetometer (VSM). The as-produced composite with an irregular flaky-shaped aggregate possesses a good anti-demagnetization ability (Hc = 861.04 G) and a high photocatalytic efficiency. Under visible light (λ > 420 nm) and UV light-emitting diode (LED) irradiation, the photodegradation rates of Rhodamine B (RhB) using BiOBr/SrFe12O19 (5 wt %) (BOB/SFO-5) after 30 min of reaction were 97% and 98%, respectively, which were higher than that using BiOBr (87%). The degradation rate of RhB using the recovered BiOBr/5 wt % SrFe12O19 (marked as BOB/SFO-5) was still more than 85% in the fifth cycle, indicating the high stability of the composite catalyst. Meanwhile, after five cycles, the magnetic properties were still as stable as before. The radical-capture experiments proved that superoxide radicals and holes were main active species in the photocatalytic degradation of RhB.

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Real-Time Healthcare Data Transmission for Remote Patient Monitoring in Patch-Based Hybrid OCC/BLE Networks

Sensors ◽

10.3390/s19051208 ◽

2019 ◽

Vol 19 (5) ◽

pp. 1208 ◽

Cited By ~ 18

Author(s):

Moh. Hasan ◽

Md. Shahjalal ◽

Mostafa Chowdhury ◽

Yeong Jang

Keyword(s):

Real Time ◽

Light Emitting Diode ◽

Health Condition ◽

High Signal ◽

Network Access ◽

Light Emitting ◽

Healthcare Data ◽

Led Array ◽

Access Request ◽

Remote Patient

Research on electronic healthcare (eHealth) systems has increased dramatically in recent years. eHealth represents a significant example of the application of the Internet of Things (IoT), characterized by its cost effectiveness, increased reliability, and minimal human eff ort in nursing assistance. The remote monitoring of patients through a wearable sensing network has outstanding potential in current healthcare systems. Such a network can continuously monitor the vital health conditions (such as heart rate variability, blood pressure, glucose level, and oxygen saturation) of patients with chronic diseases. Low-power radio-frequency (RF) technologies, especially Bluetooth low energy (BLE), play significant roles in modern healthcare. However, most of the RF spectrum is licensed and regulated, and the effect of RF on human health is of major concern. Moreover, the signal-to-noise-plus-interference ratio in high distance can be decreased to a considerable extent, possibly leading to the increase in bit-error rate. Optical camera communication (OCC), which uses a camera to receive data from a light-emitting diode (LED), can be utilized in eHealth to mitigate the limitations of RF. However, OCC also has several limitations, such as high signal-blockage probability. Therefore, in this study, a hybrid OCC/BLE system is proposed to ensure efficient, remote, and real-time transmission of a patient’s electrocardiogram (ECG) signal to a monitor. First, a patch circuit integrating an LED array and BLE transmitter chip is proposed. The patch collects the ECG data according to the health condition of the patient to minimize power consumption. Second, a network selection algorithm is developed for a new network access request generated in the patch circuit. Third, fuzzy logic is employed to select an appropriate camera for data reception. Fourth, a handover mechanism is suggested to ensure efficient network allocation considering the patient’s mobility. Finally, simulations are conducted to demonstrate the performance and reliability of the proposed system.

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Spectroscopy Transmittance by LED Calibration

Sensors ◽

10.3390/s19132951 ◽

2019 ◽

Vol 19 (13) ◽

pp. 2951 ◽

Cited By ~ 3

Author(s):

Daniel Carreres-Prieto ◽

Juan T. García ◽

Fernando Cerdán-Cartagena ◽

Juan Suardiaz-Muro

Keyword(s):

Real Time ◽

Light Emitting Diode ◽

Research Work ◽

Cost Effective ◽

Spectral Width ◽

Calibration Procedure ◽

Pollution Monitoring ◽

Light Emitting ◽

Wide Range ◽

Incandescent Lamps

Local administrations demand real-time and continuous pollution monitoring in sewer networks. Spectroscopy is a non-destructive technique that can be used to continuously monitor quality in sewers. Covering a wide range of wavelengths can be useful for improving pollution characterization in wastewater. Cost-effective and in-sewer spectrophotometers would contribute to accomplishing discharge requirements. Nevertheless, most available spectrometers are based on incandescent lamps, which makes it unfeasible to place them in a sewerage network for real-time monitoring. This research work shows an innovative calibration procedure that allows (Light-Emitting Diode) LED technology to be used as a replacement for traditional incandescent lamps in the development of spectrophotometry equipment. This involves firstly obtaining transmittance values similar to those provided by incandescent lamps, without using any optical components. Secondly, this calibration process enables an increase in the range of wavelengths available (working range) through a better use of the LED’s spectral width, resulting in a significant reduction in the number of LEDs required. Thirdly, this method allows important reductions in costs, dimensions and consumptions to be achieved, making its implementation in a wide variety of environments possible.

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