1,010 research outputs found

    Searches for vector-like quarks at future colliders and implications for composite Higgs models with dark matter

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    Many composite Higgs models predict the existence of vector-like quarks with masses outside the reach of the LHC, e.g. mQ 73 2 TeV, in particular if these models contain a dark matter candidate. In such models the mass of the new resonances is bounded from above to satisfy the constraint from the observed relic density. We therefore develop new strategies to search for vector-like quarks at a future 100 TeV collider and evaluate what masses and interactions can be probed. We find that masses as large as 3c 6.4 ( 3c9) TeV can be tested if the fermionic resonances decay into Standard Model (dark matter) particles. We also discuss the complementarity of dark matter searches, showing that most of the parameter space can be closed. On balance, this study motivates further the consideration of a higher-energy hadron collider for a next generation of facilities

    Structural, Optical and Electrical Properties of NiO Nanostructure Thin Film

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    Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 9 and 47 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.64 and 3.86 eV. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.0896 (Ω cm) – 1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

    Effect of Annealing in Physical Properties of NiO Nanostructure Thin Film

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    Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the average of the crystalline size of the deposited thin films was calculated using Debye–Scherer formula and found 46.62 for as-deposited sample and 119.89 nm for the annealed one. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging ranging 3.64 for as-deposited sample and 2.98 eV for the annealed one. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.09241 (Ωcm)−1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

    A comprehensive review of nanotechnology applications in oil and gas well drilling operations

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    The field of nanotechnology has shown promise in addressing major problems and improving drilling effectiveness. An overview of the difficulties encountered during oil and gas well drilling operations and the demand for creative solutions opens the debate. This review explores how nanotechnology is transforming the oil industry and enhancing performance as a whole. The evaluation of the uses of nanotechnology for better oil recovery, real-time monitoring, innovative materials, drilling fluids, and reservoir characterization are extensively discussed in this review. The primary function of additives is to improve the fundamental characteristics of drilling fluids. The variety of fluid additives available is a reflection of the complex drilling–fluid systems that are currently being used to enable drilling in increasingly difficult subsurface conditions. Common additives used in water- and oil-based drilling fluids include lubrication, shale stability, filtration control, rheology control, viscosification, and pH regulation. Drilling fluids frequently contain filtration control additives such as starch, polyanionic cellulose (PAC), carboxymethyl cellulose (CMC), and nanoparticles (NP). Commonly used rheology-modifier additives are xanthan gum, carboxymethyl cellulose, guar gum powder, and, more recently, salt-responsive zwitterionic polymers that were used as viscosifiers to water-based drilling fluids. The three main additives that regulate pH are citric acid monohydrate, potassium hydroxide, and sodium hydroxide. Additives that stabilize shale, such as potassium and sodium salts and asphaltenes, are often used. A wide range of materials are included in the category of lubricating additives, including polymers, asphaltenes, glass beads, oils of various grades, and oil-surfactants. Various fibrous materials, including wood, cotton, fibrous minerals, shredded tires from vehicles, and paper pulp, are used as additives to control circulation. Furthermore, shredded cellophane, bits of plastic laminate, plate-like minerals like mica flakes, granulated inert materials such as nut shells, and nano-polymers are used in wellbores to reduce fluid loss. The incorporation of nanoparticles into drilling fluids has produced upgraded fluids with better features, including improved lubricity, thermal stability, and filtering capacities. These developments aid in lowering friction, enhancing wellbore stability, and enhancing drilling efficiency. This paper also emphasizes how nanotechnology has made enhanced drilling equipment and materials possible. Drilling equipment’s longevity and performance are increased by nanocomposite materials that have been reinforced with nanoparticles due to their improved mechanical strength, wear resistance, and thermal stability. Advanced reservoir characterisation tools, including nanoparticle tracers and nanoscale imaging methods, can help locate the best drilling sites and increase production effectiveness. On the other hand, nanofluids and nanoemulsions can potentially increase oil recovery because they enhance fluid mobility, lower interfacial tension, and alter rock wettability. Although nanotechnology has many advantages, there are also issues that need to be resolved. For an implementation to be effective, factors including nanoparticle stability, dispersion, and potential environmental effects must be carefully taken into account. This review highlights the need for future research to create scalable manufacturing procedures, improve nanoparticle behaviour, and determine nanomaterials’ long-term environmental effects. In conclusion, this in-depth analysis illustrates the use of nanotechnology in transforming the process of drilling oil and gas wells

    Effect of Iron Doping on Physical Properties of NiO Thin Films

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    Nickel-iron oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of iron percentage on structural, optical and electrical properties has been studied. The crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 8.8 and 27.6 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.81 and 3.98 eV. The NiO:Fe thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.470 10 – 4 (Ω cm) – 1 for 6 % Fe can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO:Fe thin film is obtained due to the electrically low sheet resistance. NiO:Fe can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

    Structural, Optical and Electrical Properties of NiO Nanostructure Thin Film

    Get PDF
    Nickel oxide was deposited on highly cleaned glass substrates using spray pneumatic technique. The effect of precursor molarity on structural, optical and electrical properties has been studied. The XRD lines of the deposited NiO were enhanced with increasing precursor molarity due to the improvement of the films crystallinity. It was shown that the crystalline size of the deposited thin films was calculated using Debye-Scherer formula and found in the range between 9 and 47 nm. The optical properties have been discussed in this work. The absorbance (A), the transmittance (T) and the reflectance (R) were measured and calculated. Band gap energy is considered one of the most important optical parameter, therefore measured and found ranging between 3.64 and 3.86 eV. The NiO thin film reduces the light reflection for visible range light. The increase of the electrical conductivity to maximum value of 0.0896 (Ω cm) – 1 can be explained by the increase in carrier concentration of the films. A good electrical conductivity of the NiO thin film is obtained due to the electrically low sheet resistance. NiO can be applied in different electronic and optoelectronic applications due to its high band gap, high transparency and good electrical conductivity

    Heterostructured composite of NiFe-LDH nanosheets with Ti4O7 for oxygen evolution reaction

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    Developing oxygen evolution reaction (OER) electrocatalyst based on earth-abundant materials holds great promise for ascertaining water-splitting to surmount its deprived kinetics. In this regard, NiFe-LDH (layered double hydroxide) receives considerable attention owing to their layered structure. However, they still suffer from poor electronic conductivity and structural stability. We combined NiFe-LDH nanosheets with Magnéli phase Ti4O7 into a heterostructured composite. A series of analyses reveal that decorating Ti4O7 facilitates charge transfer to enhance the conductivity of NiFe-LDH-Ti4O7. During electrochemical measurement, Ni2+ is transformed to metastable Ni3+ (Ni (OH)→ NiOOH) before the OER onset potential. Thus, the presence of Ni3+ as the main active sites could improve the chemisorption of OH− to facilitate OER. As a result, the NiFe-LDH-Ti4O7 catalyst delivers as low as onset potential (1.43 V). Combining the holey structure (NiFe-LDH and Ti4O7) and the defect engineering generated on NiFe-LDH-Ti4O7 as a synergistic effect improves the OER performance. The inclusion of Ti4O7 in the composite leads to more vacancy sites, as evidenced by the extended X-ray absorption fine structure (EXAFS) analysis. The obtained defective structure with a low coordination environment would improve the electronic conductivity and facilitate the adsorption process of H2O onto metal cations, thereby increasing the intrinsic catalytic activity of NiOOH. The strong coupling of NiFe-LDH and Ti4O7 also increases the stability, and the heterostructured composite helps maintain the structural robustness of the LDH
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