UV Nonvolatile Sensor Using SANOS Capacitor Device

The silicon-aluminum oxide-nitride-silicon oxide-silicon (hereafter SANOS) could be candidates for ultra violet total dose (hereafter UV TD) nonvolatile sensors. In the case of SANOS UV TD radiation sensors, the UV radiation induces a significant increase of threshold voltage VT. The changes of VT for SANOS after UV radiation have a correlation to the UV TD as well. In this paper, the performance for capacitor types of SANOS UV TD nonvolatile sensor were discussed in detailed. The SANOS capacitor device in this study has demonstrated the better feasibility for UV TD nonvolatile sensor application.

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Improve the Performance of SONOS Type UV TD Sensors Using IOHAOS with Enhanced UV Transparency ITO Gate

Coatings ◽

10.3390/coatings11040408 ◽

2021 ◽

Vol 11 (4) ◽

pp. 408

Author(s):

Wen-Ching Hsieh ◽

Fun-Cheng Jong ◽

Wei-Ting Tseng

Keyword(s):

Aluminum Oxide ◽

Threshold Voltage ◽

Indium Tin Oxide ◽

Silicon Oxide ◽

Poly Silicon ◽

Ito Film ◽

Post Annealing ◽

Response Performance ◽

Fading Rate ◽

Silicon Device

This research demonstrates that an indium tin oxide–silicon oxide–hafnium aluminum oxide‒silicon oxide–silicon device with enhanced UV transparency ITO gate (hereafter E-IOHAOS) can greatly increase the sensing response performance of a SONOS type ultraviolet radiation total dose (hereafter UV TD) sensor. Post annealing process is used to optimize UV optical transmission and electrical resistivity characterization in ITO film. Via nano-columns (NCols) crystalline transformation of ITO film, UV transparency of ITO film can be enhanced. UV radiation causes the threshold voltage VT of the E-IOHAOS device to increase, and the increase of the VT of E-IOHAOS device is also related to the UV TD. The experimental results show that under UV TD irradiation of 100 mW·s/cm2, ultraviolet light can change the threshold voltage VT of E-IOHAOS to 12.5 V. Moreover, the VT fading rate of ten-years retention on E-IOHAOS is below 10%. The VT change of E-IOHAOS is almost 1.25 times that of poly silicon–aluminum oxide–hafnium aluminum oxide–silicon oxide–silicon with poly silicon gate device (hereafter SAHAOS). The sensing response performance of an E-IOHAOS UV TD sensor is greatly improved by annealed ITO gate.

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Extensive reduction of surface UV radiation since 1750 in world's populated regions

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-7737-2009 ◽

2009 ◽

Vol 9 (20) ◽

pp. 7737-7751 ◽

Cited By ~ 7

Author(s):

M. M. Kvalev&aring;g ◽

G. Myhre ◽

C. E. Lund Myhre

Keyword(s):

Uv Radiation ◽

Correlation Coefficients ◽

Ultra Violet ◽

Radiative Transfer Model ◽

Transfer Model ◽

Polar Regions ◽

Ultra Violet Radiation ◽

Wide Range ◽

Extensive Surface ◽

Year 2000

Abstract. Human activity influences a wide range of components that affect the surface UV radiation levels, among them ozone at high latitudes. We calculate the effect of human-induced changes in the surface erythemally weighted ultra-violet radiation (UV-E) since 1750. We compare results from a radiative transfer model to surface UV-E radiation for year 2000 derived by satellite observations (from Total Ozone Mapping Spectroradiometer) and to ground based measurements at 14 sites. The model correlates well with the observations; the correlation coefficients are 0.97 and 0.98 for satellite and ground based measurements, respectively. In addition to the effect of changes in ozone, we also investigate the effect of changes in SO2, NO2, the direct and indirect effects of aerosols, albedo changes and aviation-induced contrails and cirrus. The results show an increase of surface UV-E in polar regions, most strongly in the Southern Hemisphere. Furthermore, our study also shows an extensive surface UV-E reduction over most land areas; a reduction up to 20% since 1750 is found in some industrialized regions. This reduction in UV-E over the industrial period is particularly large in highly populated regions.

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ULTRA VIOLET DETECTION SENSORS

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156406003862 ◽

2006 ◽

Vol 16 (02) ◽

pp. 583-588

Author(s):

Vahé NERGUIZIAN ◽

Mustapha RAFAF ◽

Muthukumaran PACKIRISAMY ◽

Ion STIHARU

Keyword(s):

Human Skin ◽

Uv Radiation ◽

Radiation Risk ◽

Ultra Violet ◽

Visual Monitoring ◽

Ultra Violet Light ◽

Actuation Mechanism ◽

Violet Light ◽

Uv Sensors ◽

Chemical Material

This article presents an innovative and creative approach to detect harmful level of Ultra Violet light on human skin. Different commercial UV sensors are evaluated for comparison. The comparison is made for performance, cost and dimension. The proposed affordable UV sensor solutions are presented using chemical and MEMS/MOEMS technologies. The UV dynamic sensor detects the harmful level of UV and informs the user about the eventual UV radiation risk. The proposed two solutions consider chemical material for UV detection and different actuation mechanism to inform the UV harmful level to the user. These sensors are non disposable and are packaged for visual monitoring (without battery) and acoustic operation (using a battery).

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Plasma agriculture based on quantitative monitoring of reactions between fungal cells and atmospheric-pressure plasmas

MRS Proceedings ◽

10.1557/opl.2012.1008 ◽

2012 ◽

Vol 1469 ◽

Cited By ~ 4

Author(s):

Masafumi Ito ◽

Takayuki Ohta ◽

Keigo Takeda

Keyword(s):

Uv Radiation ◽

Absorption Spectroscopy ◽

Ground State ◽

Atmospheric Pressure ◽

Atomic Oxygen ◽

Fungal Spores ◽

Ultra Violet ◽

High Density ◽

Inactivation Rate ◽

The Absolute

ABSTRACTA high-density non-equilibrium atmospheric pressure plasma (NEAPP) applied for inactivating fungal spores of P. digitatum is introduced as an environmentally safe and rapid-inactivation method. The contributions of ozone, ultra violet (UV) radiation and ground-state atomic oxygen in the NEAPP on the inactivation of the spores are evaluated using colony count method.The absolute densities of ozone were measured by using ultraviolet absorption spectroscopy. The ozone density increased from 2 to 8 ppm with an increase in the distance from the plasma source, while the inactivation rate decreased. The inactivation rate of plasma was evaluated to be thousand times higher than that of an ozone generator using the integrated number density of ozone. In addition, it was clarified that the contribution of UV radiation to inactivation was not dominant for P. digitatum inactivation by NEAPP by filtering the active species using quartz plate. From these results, we can speculate that the inactivation efficiency of reactive oxygen species (ROS) will be larger than those of others.In order to investigate the effect of ground-state atomic oxygen as one of ROS, the inactivation of P. digitatum spores using an oxygen radical source that employs a high-density atmospheric-pressure O2/Ar plasma. The absolute O density was measured to be 1.4×1014 and 1.5×1015 cm–3 using vacuum ultra violet absorption spectroscopy (VUVAS) using a microdischarge hollow cathode lamp. The behaviors of the O densities as a function of O2/(Ar+O2) mixture flow rate ratio correspond to that of the inactivation rate. This result indicates that ground-state atomic oxygen is concluded to be the dominant species that causes inactivation.

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Nanofluids, Synthesis and Stability - Brief Review

ESPOCH Congresses: The Ecuadorian Journal of S.T.E.A.M. ◽

10.18502/espoch.v1i2.9520 ◽

2021 ◽

Author(s):

Jorge Silva-Yumi ◽

Telmo Moreno Romero ◽

Gabriela Chango Lescano

Keyword(s):

Carbon Nanotubes ◽

Thermal Properties ◽

Ethylene Glycol ◽

Aluminum Oxide ◽

Titanium Oxide ◽

Silicon Oxide ◽

Physical Treatment ◽

Natural Nanoparticles ◽

Palabras Clave ◽

Hybrid Nanofluids

Nanofluids constitute an alternative for the most efficient use of energy as they allow generating or improving thermal properties among others of traditional fluids, they are defined as so-called base fluids, such as: water, ethylene glycol, oils, etc., which contain nanoparticles in suspension , such as: aluminum oxide, silicon oxide, titanium oxide, metal nanoparticles, carbon nanotubes, graphene, carbides, etc. Nanofluids can be synthesized by two methods, the nanoparticles can be obtained separately and then the nanofluid is prepared or both nanoparticles and the nanofluid can be prepared simultaneously, an important factor to consider in obtaining nanofluids is their stability. Stability can be achieved by physical treatment or chemical treatment using surfactants. There are many studies about nanofluids, however, most are obtained with synthetic nanoparticles, leaving the use of natural nanoparticles as a field to be explored, as well as other surfactants to improve their stability. Keywords: nanofluids, hybrid nanofluids, nanoparticles, nano refrigerant. Resumen Los nanofluidos constituyen una alternativa para el uso más eficiente de energía pues permiten generar o mejorar las propiedades térmicas entre otras de los fluidos tradicionales, son definidos como fluidos denominados base, como: agua, etilenglicol, aceites, etc., que contienen nanopartículas en suspensión, como: óxido de aluminio, óxido de silicio, óxido de titanio, nanopartículas metálicas, nanotubos de carbono, grafeno, carburos, etc. Los nanofluidos se pueden sintetizar por dos métodos, se pueden obtener las nanopartículas por separado y luego preparar el nanofluido o se puede preparar simultáneamente las nanopartículas y el nanofluido, un factor importante a considerar en la obtención de nanofluidos es su estabilidad. La estabilidad se puede lograr mediante tratamiento físico o tratamiento químico mediante la utilización de surfactantes. Existen muchos estudios acerca de nanofluidos sin embargo, la mayoría se obtienen con nanopartículas sintéticas, quedando el uso de nanopartículas naturales como un campo por explorar al igual que otros surfactantes para mejorar su estabilidad. Palabras Clave: nanofluidos, nonofluidos híbridos, nanoparticulas, nanorefrigerantes.

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BIOACTIVE ASSESSMENT AND BACTERIA TEST FOR THE VARIED DEGREES OF ULTRA-VIOLET RADIATION ONTO THE COLLAGEN-IMMOBILIZED POLYPROPYLENE NON-WOVEN FABRIC

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237202000048 ◽

2002 ◽

Vol 14 (01) ◽

pp. 20-30 ◽

Cited By ~ 1

Author(s):

JIUNN-DER LIAO ◽

YU-CHANG TYAN

Keyword(s):

Red Blood Cells ◽

Human Plasma ◽

Uv Radiation ◽

Blood Cells ◽

Ultra Violet ◽

Woven Fabric ◽

Plate Count ◽

Fibrinogen Concentration ◽

Thrombin Time ◽

Chemical Structures

Exposure to ultra-violet (UV)-C radiation is a frequently used method to prevent bacteria from invasion of blood-contact biomedical products. Potential damage induced by UV radiation to collagen is of concern due to the decay of bioactivity, considerably correlated with structural alterations. Current investigation indicates to the collagen-immobilized non-woven polypropylene (PP) fabrics with sample temperature ca. 4 °C; the samples are then exposed to UV-254 nm radiation for different time intervals. Using Fourier-Transformed Infrared with Attenuated Total Reflection (FTIR-ATR) and XPS (X-ray Photoelectron Spectroscopy), we examine the chemical structures of samples with different treatments. Blood-clotting effects on the modified samples are assessed by activated partial thromboplastin time, thrombin time, and fibrinogen concentration tests. By means of cell counter and Scanning Electron Microscopy we count red blood cells and platelets adhesion in the modified porous matrix. Applying standard plate count for bacteria tests, E. coli, Bacillus stearothermophilus, Staph. aureus, P. aeruginosa, and Candida albieans are applied. For human plasma incubated samples of various intervals of UV-254 nm radiation, fibrinogen concentration decreases in human plasma, while platelets and red blood cells adhesions increase before UV radiation. The required time for thrombination shows significant change for UV exposure of less than 20 hrs (α = 0.05). Surface analyses indicate that the decrease of R-COOH (derivated from grafted-pAAc or decarboxylation of collagen), amides degradation (broken–NH), and phenylalanine scission (terminated by −OH, tyrosine formation) may gradually damage collagen by increasing the intervals of UV radiation. The XPS measurements of C 1s core levels at 288.1 eV (O=C-NH) and at 289.3 eV (O=C-O) illustrate significant decreases of intensity after radiation time ca. 44 hrs. It is clear that UV-254 nm radiation exposure for ca. 20 hrs has the potential impact to moderate the bioactivities of collagen and therefore act as a vital factor to accelerate bio-degradation. Bacteria test also supports that around 20 hrs of UV radiation, no bacteria clone formation is found on the immobilized collagen. However, the relation between eventual bioactivity of immobilized collagen after UV radiation and the capability of bacteria proliferation should be measured.

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