CaO-P2O5-SiO2-B2O3-ZnO bioactive glasses were prepared via an optimized sol–gel method. The current investigation was focused on producing novel zinc based calcium phosphoborosilicate and to evaluate their mechanical, rheological biocompatible properties. morphology composition of these studied using X-ray diffraction (XRD) scanning electron microscopy (SEM). particle size, mechanical flexural strength also determined. Furthermore, the zeta potential all determined estimate flocculation...

This Letter introduces a fiber Bragg grating (FBG) in micro-single-crystal sapphire (micro-SFBG) for sensing applications high-temperature and harsh environments. The FBG was fabricated by point-by-point method via an IR-femtosecond laser large-diameter that then wet-hot acid etched to achieve microfiber size, which culminated fabricating characterizing 9.6 μm diameter micro-SFBG. refractive index measurement ranging from 1 1.75 temperature room 1400°C are also reported.

We present, for the first time to our knowledge, a sapphire-fiber-based distributed high-temperature sensing system based on Raman technique. High peak power laser pulses at 532 nm were coupled into sapphire fiber generate signal. The returned Stokes and anti-Stokes signals measured in domain determine temperature distribution along fiber. sensor was demonstrated from room up 1200°C which average standard deviation is about 3.7°C spatial resolution of 14 cm achieved.

Single-crystal sapphire fibers have a very high melting point (up to 2050°C), which renders them good candidate for sensing applications at temperature. We present in this paper the recent work of developing single-crystal fiber extrinsic Fabry-Perot interferometric strain sensors based on white-light spectrum demodulation technique. Prototype were fabricated and tested temperatures up 1004°C. The preliminary experimental results indicate that are promising be used under high-temperature...

A novel diaphragm-based miniature optical fiber pressure sensor has been shown to work at temperatures up 700/spl deg/C with a sensitivity of 2.93 nm/psi and resolution 0.01 psi (68.9 Pa). passive temperature compensation scheme was used reduce the dependence 0.0076 psi//spl (52.4 Pa//spl deg/C). The exhibited linear response in available testing range from 0 200 (1.38 MPa), being composed entirely fused silica, sensor's structure is very reliable, corrosion resistant, immune electromagnetic...

Research on development of optical gas sensors based evanescent-wave absorption in random-hole fibers is described. A process to produce was recently developed that uses a novel situ bubble formation technique. Gas molecules exhibit characteristic vibrational lines the near-IR region correspond transmission window for silica fiber have been detected through evanescent field guided mode pore region. The presence holes appears as loss at wavelengths are particular species present holes. An...

We investigated the capability of biodegradable silica xerogel as a novel carrier antibiotic and efficacy treatment compared to that with same dose free drug against murine salmonellosis. The molecules (31%) entrapped in sol-gel matrix remained biologically active form, bactericidal effect was retained upon release. vitro release profiles gentamicin from xerogel-polyethylene glycol (PEG) were distinctly different at pH 7.4. A delayed observed network (57% 33 h), addition 2% PEG, rate reached...

Readily available temperature sensing in boilers is necessary to improve efficiencies, minimize downtime, and reduce toxic emissions for a power plant. The current techniques are typically deployed as single-point measurement primarily used detection prevention of catastrophic events due the harsh environment. In this work, multi-point sensor based on wavelength-multiplexed sapphire fiber Bragg gratings (SFBGs) were fabricated via point-by-point method with femtosecond laser. was packaged...

Fiber-optic sensing has shown promising development for use in detecting magnetic fields downhole and biomedical applications. Coupling existing fiber-based strain sensors with highly magnetostrictive materials allows a new method of characterization capable distributed high-sensitivity field measurements. This study investigates the response alloys Metglas® 2605SC Vitrovac® 7600 T70 using Fiber Bragg Grating (FBG) acoustic an applied AC field. Sentek Instrument’s picoDAS interrogated FBG...

We present a novel signal-processing algorithm for single-mode optical fiber extrinsic Fabry–Perot interferometric sensors that can achieve both high-resolution, absolute measurement of the cavity length and large dynamic range simultaneously. The is based on an accurate model characteristics fiber-optic sensor takes into account phase shift due to coupling light reflected at second surface lead-in end.

Modern high-temperature processes, such as fossil energy production, nuclear reactors, and chemical reactors lack robust, distributed sensing systems to map temperatures in these high-value harsh-environment systems. Regular silica-fiber-based temperature usually only operate at below about 800 °C. In this paper, we present the design, implementation, testing of a ultra-high system using Raman scattering intensity, which operates from room above 1400 Consideration is given impacts thermal...

In this research, for the first time, an n-type silicon optical fiber is demonstrated. The fabricated by drawing from a powder-in-tube-type preform. Outside diameters in range of several hundred micrometers were made with core tens micrometers. Optical and material characterizations have been order to understand structural compositional properties device. Fibers polycrystalline few large grains as determined electron backscatter diffraction analysis. Grains' dimensions are on hundreds doped...

High temperature sensor with robust performance, minimum footprint, and fast response is desirable for many applications in extreme environments. This article introduces a miniature high based on fiber Fabry-Perot interferometer. The interferometric cavity directly fabricated the tip of 125 μm single-crystal sapphire through femtosecond laser micromachining CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> welding as light-guiding...

We study the point-by-point inscription of sapphire parallel fiber Bragg gratings (sapphire pFBGs) in a fully multimode system. A FBG is shown to be critical enabling detectable and reliable high-order grating signals. The impacts modal volume, spatial coherence, location on reflectivity are examined. Three cascaded seventh-order pFBGs fabricated one for wavelength multiplexed temperature sensing. Using low-cost, 850-nm interrogator, measurement up 1500°C demonstrated.

Sensitivity, fringe contrast, and dynamic range are the three most important parameters in theoretical performance evaluation of fiber Fabry-Pe/spl acute/rot (F-P) interferometric sensors. This paper theoretically models effect that cavity length, F-P finesse, source bandwidth, mirror misalignments symmetry play sensitivity, a interferometer interrogated with low-coherence light source. The developed systematic analysis approach numerical results on both guided unguided (FFPI) sensors may...

Long-period grating (LPG) structures including cascaded LPGs on step index fibers and photonic crystal were coated with thin films of diamond-like carbon (DLC) using plasma deposition techniques. Improvements in the coating procedures increased sensitivity to external refractive variations indicating significant improvements sensing capability hybrid structures. DLC range tens nanometers significantly all tested.

The observation of single mode propagation in an air-clad crystal sapphire optical fiber at wavelengths and above 783 nm is presented for the first time. A high-temperature wet acid etching method was used to reduce diameter a 10 cm length commercially-sourced from 125 micrometers 6.5 micrometers, far-field imaging provided modal information intervals as decreased. Modal volume shown decrease with decreasing diameter, behavior observed minimum achieved. While weakly-guiding approximations...

Detailed studies on fiber optic pressure and temperature sensors for oil down-hole applications are described in this paper. The sensor head is an interferometric based senor which the air-gap will change with or temperature. For high-speed applications, a novel self-calibrating interferometric/intensity-based (SCIIB) scheme, realizes compensations both light source drift loss variation, was used to demodulate (or temperature) signals. An improved white system developed fabrication. This...