In the oil and gas, CO2 sequestration, H-2 subsurface storage, and geothermal energy sectors, subsurface pH measurements are critical for monitoring the geochemical conditions and structural integrity of wellbore syst...
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ISBN:
(纸本)9781510661783;9781510661790
In the oil and gas, CO2 sequestration, H-2 subsurface storage, and geothermal energy sectors, subsurface pH measurements are critical for monitoring the geochemical conditions and structural integrity of wellbore systems. Real-time pH measurements in these conditions are vital for detecting and predicting corrosion deterioration of wellbore components that may jeopardize the safety and continued operation of wellbore systems. The viability of TiO2-coated optical fibers has previously been demonstrated as an effective sensor design for continuous distributed pH monitoring at elevated temperatures and ambient pressures. However, real wellbore conditions contain high pressures and the effects of high pressures on sensor results and the sensing layer have not been well studied. As TiO2 has been established in the literature as being stable at temperatures and pressures substantially higher than those expected in typical wellbore conditions, it makes for a promising sensing material for applications requiring high-pressure, high-temperature (HPHT) conditions. In this study, a sol-gel deposition method is used to coat the optical fiber sensors with TiO2 sensing layer. The sensor performance was measured using optical transmission measurements at various pH and using optical backscatter reflectometry for distributed pH sensing demonstration in wellbore-relevant pressures (up to 1000 psi) and temperatures (similar to 80 degrees C). The TiO2 sensing layer was characterized using scanning electron microscopy (SEM) and full spectrum UVVis-NIR transmission data for a planar substrate. The TiO2-coated optical fiber sensor is tested for any pressure-derived effects and the viability of this sensor design for real-time in-situ wellbore pH monitoring is discussed.
With the rapid development of urban rail transit, there are efficiency issues in the assembly, commissioning, daily operation, and maintenance of urban rail air conditioning systems. In addition, there is a shortage o...
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This study presents a novel method for enhancing the performance of near-infrared (NIR) optical metasurfaces by integrating Ge2Sb2Te5 (GST) phase-change materials with graphene plasmonic properties. By leveraging loca...
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ISBN:
(纸本)9798350363524;9798350363517
This study presents a novel method for enhancing the performance of near-infrared (NIR) optical metasurfaces by integrating Ge2Sb2Te5 (GST) phase-change materials with graphene plasmonic properties. By leveraging local graphene heaters, the phase of incident light is precisely controlled, dynamically adjusting the crystallization levels of GST and altering the metasurface's optical behavior. This approach utilizes surface plasmon polaritons to achieve improved absorption rates and a dynamic phase modulation range of 0 degrees to 300 degrees for reflected waves at a wavelength of 1.55 mu m. Finite element method (FEM) simulations validate the effectiveness of the proposed design, demonstrating significant potential for applications in beam steering, LiDAR systems, and reconfigurable optical devices. Key parameters such as resonance frequency, quality factor, and reflection coefficient are meticulously engineered, highlighting the versatility and efficiency of GST-based metasurfaces in advanced photonic technologies.
Flow velocity measurement is an important part in hydrological monitoring activities. Aiming at the problems of low accuracy and long time of velocity measurement in current flow velocity radar, we design a millimeter...
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Underwater optical communication links, mult hop scattering may result in beam temporal spread characterized via the impulse response, which causes in interference and deteriorates system performance. Thence, an under...
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Lightning ignition source protection design of aircraft fuel system is an important factor affecting aircraft flight safety. There are many factors related to ignition source, and there exist optimization possibilitie...
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A novel packaging configuration was developed for a 300 mm wafer scale system. A number of these systems have been operated at power levels up to about 16 kW for over a year using a thermal test wafer. The power subsy...
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Pneumatically-driven Soft Growing Robots (SGR) are a new class of continuum robots, which take inspiration from vines, mimicking their capability to evolve along a path from the tip, while being intrinsically safe tow...
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ISBN:
(纸本)9783031765964;9783031765971
Pneumatically-driven Soft Growing Robots (SGR) are a new class of continuum robots, which take inspiration from vines, mimicking their capability to evolve along a path from the tip, while being intrinsically safe towards the environment. The SGRs' capabilities can be empowered by providing them with the capability to mount sensors and tools at the tip, thus enabling many applications in unstructured environments, such as object transportation in constrained spaces. However, the tip position of SGRs changes over time during growth, making it challenging to keep tools attached at the tip in the desired configuration. An auxiliary device at the tip is required, which grows with the SGR without hindering the eversion or changing the robot's designed shape. In this work, currently implemented designs in the literature for enabling SGRs tip-attachment are analyzed. Then, a novel tip-mounted Hybrid Magnetic Cap (HMC), composed of textile and rigid components, is presented;this dual nature makes the device both safe and efficient during all the SGR operative phases. To prove its effectiveness, this design is applied to a specific case study: cable delivery along a straight path. It is demonstrated how this tip-mounted HMC can successfully enable and automate such a delicate task in a very short time.
The paper presents an all-optical OR logic gate utilizing the phenomenon of light beam interference. The silicon substrate contains a two-dimensional photonic crystal (2D-PC) structure, which is created by arranging a...
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The distance measurement based on binocular stereo vision is suitable for online and non-contact target detection because of its advantages including high efficiency, simple system structure and low cost. However, the...
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