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III–V Nanowires: Transistor and Photovoltaic Applications
Published in Fumitaro Ishikawa, Irina A. Buyanova, Novel Compound Semiconductor Nanowires, 2017
Katsuhiro Tomioka, Junichi Motohisa, Takashi Fukui
InAs/undoped InAlAs/Si-doped InAlAs CMS NWs have been investigated in attempts to passivate the surface of InAs NWs. An undoped-InAlAs/Si-doped InAlAs multilayer is grown on the sidewalls of the InAs NWs by using the lateral over growth mode of selective-area MOVPE (SA-MOVPE) (Fig. 14.6a) after growth of the InAs NWs on Si (Fig. 14.6b). Fig. 14.6c shows the resultant growth on Si(111).The diameter of the CMS NWs during the InAlAs growth increased from 80 to 140 nm, while the average height of the InAs/InAlAs CMS NWs remained constant at 1.25 μm after the formation of the InAs/InAlAs CMS structures. This means that the InAlAs layers grew only radially in the <–110> directions. The thicknesses of the n-InAlAs and undoped- InAlAs shell layer were 23 and 7 nm, respectively.
Wave Packet and de Broglie's Wave-particle Duality
Published in Caio Lima Firme, Quantum Mechanics, 2022
De Broglie proposed the matter waves where the mass m is corrected according to the equation from special relativity where he used V to represent the phase velocity [cms−1] of the propagating waves. The phase velocity can be expressed in terms of the wavelength λ and the frequency v.
Applications
Published in Cinzia Da Vià, Gian-Franco Dalla Betta, Sherwood Parker, Radiation Sensors with Three-Dimensional Electrodes, 2019
Cinzia Da Vià, Gian-Franco Dalla Betta, Sherwood Parker
Other experiments that are presently using 3D sensors are the Atlas Forward Physics (AFP) [12] and the CMS TOTEM precision proton spectrometer (CT-PPS) [13]. These detectors measure the diffractive proton–proton scattering at the ATLAS and CMS experiments, respectively. Very simply: in diffractive scattering, two protons will not collide to produce other particles but will pass close enough to one another to exchange a so-called pomeron and then continue their trajectory intact in the beam pipe. This pomeron exchange, however, would have modified the momentum, and hence the trajectory of each of the two emerging protons that can now be detected if a sensor is placed as close as possible to the beam and at reasonable distance from the point where the two protons met. The radial distance from the beam at which the protons will appear is a direct measurement of their new momentum. The radiation tolerance requirements for the sensors used to measure such momentum are equivalent to the one experienced by the innermost layers of the central detectors, with the difference, however, that they are distributed asymmetrically over the sensing volume. Most of the damage caused by the protons will concentrate in the region near the beam. Ideally, a detector in this region would be divided into separate sections, with separate bias voltages to respond to this asymmetric irradiation [14]. However, 3D sensors have been shown to be robust enough to withstand the increase of bias voltage required after irradiation, even in the moderately irradiated regions, making them ideal for the task. Furthermore, as shown in detail previously, 3D sensors offer the possibility of reducing the dead area at the module's edges by using “active edges” or “slim edges” to record as many events close to the beam as possible. Results from 3D sensors with the same geometry as those installed in the IBL, but with a modified slim edge, are encouraging. As a further example of the requirements of detectors for such experiments, AFP plans to place such detectors symmetrically at 220 m from the ATLAS experiment beam interaction point to precisely measure such events and extract the physics information related to the optical properties of the protons.
Assessment of expanded polystyrene as a separator in microbial fuel cell
Published in Environmental Technology, 2019
Abhilasha Singh Mathuriya, Deepak Pant
Nafion 117® is known for its high water uptake efficiency and high cost, which hinders its application on a large scale. In addition, Nafion 117® cannot operate efficiently at a higher temperature due to its thermal instability [48]. Furthermore, during the 60 days of operation, mottled biofouling with dense extracellular polymer substance was observed on the surface of Nafion 117. This indicates contamination of Nafion 117 by microorganism after operation [31]. In another study, the presence of a carbonaceous substance on Nafion was observed during operation [49]. Very recently, Daud et al. [50] compared the performance of ceramic membranes (CMs) of different pore sizes with CEM, and Nafion 117 in two-chamber MFCs. MFC with CMs exhibited a higher performance. This study reveals that PEM, Nafion 117, contains hydrophilic sulfonate groups (), without any pores, whereas CMs are porous. The porous structure of the ceramics may improve the efficiency of proton transfer through the separators. The CMs function as non-ion selective charge transfers and have good ionic (proton and cations) transfer compared to PEM, Nafion 117 when used as a separator in MFCs.
Magnetic Fe3O4-chitosan micro- and nanoparticles for wastewater treatment
Published in Particulate Science and Technology, 2019
Deniz Akın Sahbaz, Arzu Yakar, Ufuk Gündüz
Figure 4 shows the average diameter and size distribution of the naked Fe3O4 nanoparticles, Fe3O4-CNs, and Fe3O4-CMs. The size of the Fe3O4-CNs (Figure 4b) ranged from 15 to 20 nm, and the mean diameter was 18 nm which was a little bigger than the size of the naked Fe3O4 nanoparticles (Figure 4a). On the other hand, the size distribution of Fe3O4-CMs (Figure 4c) is wide and has two peaks ranging from hundreds of nanometers to micrometers.
A High-Precision Tagged Neutron n-p Scattering Measurement at 14.9 MeV
Published in Nuclear Science and Engineering, 2020
N. V. Kornilov, S. M. Grimes, T. N. Massey, C. E. Brient, D. E. Carter, J. E. O’Donnell, K. W. Cooper, A. D. Carlson, F. B. Bateman, C. R. Heimbach, N. Boukharouba
It is clearly visible from Fig. 18 that results from neutron and proton counting experiments are in perfect agreement in the CMS cosine range >−0.7. The fitted functions describe both data sets with very high accuracy (χ2 ≪ 1). This result confirms the conclusion that was made previously: The main contribution in STD for data collected in Table I is connected with systematical deviation, not with random component. The STD for the ratio of the fitted function (Fig. 18) to ENDF/B-VII data is 1.8%.