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51.
Crystalline Na3Bi2P3O12, K3Bi2P3O12 and glassy K3Bi2P3O12 compounds were prepared by solid-state reaction method. The prepared samples are characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetry. The crystalline materials are found to be orthorhombic. The electrical conductivity measurements on the crystalline and glassy samples show that at ∼373 K, the σDC for crystalline K3Bi2P3O12 (0.81 × 10−8 S/cm) is about two orders of magnitude higher than the corresponding glassy phase (1.25 × 10−10 S/cm). The scaling results show that the conductivity relaxation mechanism is independent of temperature.  相似文献   
52.
Recycled high‐density polyethylene (HDPE) was incorporated with graphene nanoflakes in a solvent at different concentrations (0, 1, 2, 4, and 8 wt%), and then the mechanical, thermal, electrical, and surface hydrophobic properties of the resultant nanocomposites were determined using universal tensile testing, thermal comparative, capacitance bridge, and goniometer techniques, respectively. The test results revealed that the mechanical, thermal, and dielectric properties of the polymer matrix nanocomposites were increased as a function of graphene concentrations, whereas the surface hydrophobic values were slightly increased at lower concentrations and then reduced at higher concentrations. These improvements occur mainly because of the excellent properties of graphene nanoflakes, such as tensile strength (150 GPa), Young's modulus (1.0 TPa), thermal conductivity (4,840–5,300 W/m K), electrical conductivity (1.3 × 106 S/cm), electrical current density (1013 A/cm2), surface hydrophobicity (>120°), and surface smoothness/roughness (<1 nm). The worldwide consumption of polymeric products has been drastically growing, and consequently polymeric waste materials have been rising up, as well. Although the plastic recycling and reprocessing rates are considerably high, physical properties and economical values of the recycled plastics are significantly low, limiting the reuse of recycled plastics in many industrial applications. As a result, this study provides a detailed explanation of how to improve recycled plastics into highly valued new products for applications in various industries, such as transportation, energy, electronic, construction, and so forth. POLYM. COMPOS., 36:1565–1573, 2015. © 2014 Society of Plastics Engineers  相似文献   
53.
The corrosion behaviour of AISI type 304L stainless steel (SS) in different concentration of 0.01 M, 1 M and 5 M HNO3 in presence of oxidizing ions at different temperatures has been evaluated. The main objective of this study is to assess the corrosion resistance of type 304L SS in non-radioactive conditions encountered during storage of liquid nuclear waste. Electrochemical impedance spectroscopy (EIS) and laser Raman spectroscopy (LRS) has clearly brought out the deleterious effect of oxidizing species on the passive film leading to increased corrosion along with increase in HNO3 concentration and higher temperature.  相似文献   
54.
This paper presents the Electrochemical Potentiokinetic Reactivation (EPR) parameters obtained for non-sensitised 316LN stainless steel containing sulphide/oxysulphide inclusions. Even in the absence of sensitization, reactivation peaks were obtained in single loop and double loop EPR experiments for longitudinal and cross transverse sections. Using Laser Raman Spectroscope, Raman maps of Cr (VI) oxide were obtained around the inclusions. It was inferred that the reactivation peak is due to dissolution of sulphide inclusions and chromium depleted zones arising around chromium segregated flow lines. The need to interpret EPR parameters carefully in the presence of sulphide inclusions is emphasised.  相似文献   
55.
Synergistic hydrogen-bonded interaction of alkyl benzimidazoles and 1,2,3-benzotrizole and its corrosion protection properties on mild steel in hydrochloric acid at different temperatures have been studied using polarization, EIS, adsorption, surface studies, and computational methods. The extent of synergistic interaction increases with temperature. Quantum chemical approach is used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect, and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to some parameters, such as total energy, E HOMO, E LUMO, and gap energy (ΔE). 1,2,3-Benzotrizole interacts with benzimidazoles derivatives up to a bond length of approximately 1.99 Å. This interaction represents the formation of a hydrogen bond between the 1,2,3-benzotrizole and benzimidazoles. This synergistic interaction of 1,2,3-benzotrizole and benzimidazole derivatives offers extended inhibition efficiency toward mild steel in hydrochloric acid.  相似文献   
56.
The corrosion protection efficiency of MBIMOT, 5-((2-methyl-1H-benzo[d]imidazol-1-yl) methyl)-1, 3, 4 oxadiazole-2-thiol towards mild steel (MS) in HCl and its variation with inhibitor concentration, acid concentration and temperature were assessed by weight loss and electrochemical methods. Corrosion rate found to decrease with increasing the concentration of MBIMOT and increase with temperature and acid concentration. Electrochemical impedance spectroscopy studies revealed that the adsorption of MBIMOT on MS surface follow Langmuir isotherm. The mixed type behavior of MBIMOT is evidenced from the polarization curves. Various kinetic and thermodynamic parameters were calculated. The molecular level understanding of corrosion inhibition done by DFT approach revealed a preferential adsorption of thione form of MBIMOT over thiol form on MS surface.  相似文献   
57.
Kondavitee  Girija Sravani  Rao  K. Srinivasa  Suman  M.  Pravallika  B.  Annapurna  K. Sravani  Vaishnavi  G.  Ramya  K. Ruth  Aditya  M. 《SILICON》2023,15(5):2199-2209
Silicon - This paper presents the design and simulations of 5&nbsp;nm HEMT. The analysis of analog parameters, electrical parameters and the RF performance of the 5&nbsp;nm HEMT has been...  相似文献   
58.
Access to the cochlea requires drilling in close proximity to bone-embedded nerves, blood vessels, and other structures, the violation of which can result in complications for the patient. It has recently been shown that microstereotactic frames can enable an image-guided percutaneous approach, removing reliance on human experience and hand-eye coordination, and reducing trauma. However, constructing current microstereotactic frames disrupts the clinical workflow, requiring multiday intrasurgical manufacturing delays, or an on-call machine shop in or near the hospital. In this paper, we describe a new kind of microsterotactic frame that obviates these delay and infrastructure issues by being repositionable. Inspired by the prior success of bone-attached parallel robots in knee and spinal procedures, we present an automated image-guided microstereotactic frame. Experiments demonstrate a mean accuracy at the cochlea of 0.20 ± 0.07 mm in phantom testing with trajectories taken from a human clinical dataset. We also describe a cadaver experiment evaluating the entire image-guided surgery pipeline, where we achieved an accuracy of 0.38 mm at the cochlea.  相似文献   
59.
Lokesh  S.  Kanisha  B.  Nalini  S.  Ramya Devi  M.  Kumar  R. 《Multimedia Tools and Applications》2020,79(7-8):5023-5042
Multimedia Tools and Applications - In general, visually impaired students need of another person’s to teach them with the help of computers and book. However, a number of students are not...  相似文献   
60.
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