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In this article, analysis of heating effect for a range of thermal resistance (Rth) and different ambient temperatures on the DC parameters of the proposed Silicon‐Gate All Around Dielectric Window Spaced‐Multi‐channel (Si‐GAA‐DWS‐multi‐channel) MOSFET is carried out. The performance of the device is examined through 3D‐ATLAS TCAD simulator, by performing the numerical and electrothermal analysis. Due to cylindrical dimension, the nanowire FETs undergoes undesirable self/lattice‐heating. The lattice heating of the device is calculated with respect to various device parameters such as channel length, drain‐source voltage, thermal resistance, ambient temperature, on‐current Ion, and off‐current Ioff. The proposed device parameter has been compared with the existing devices, mainly with Silicon‐Nanowire‐Dielectric Pocket Packed MOSFET (Si‐NW‐DPP FET) and Silicon‐Nanowire MOSFET (Si‐NW FET). The Si‐GAA‐DWS‐multi‐channel FET is found to be as the better device than the other two structures, as the leakage current of the device is improved by 1 and 2 decades, drain current increases by 1 and 1 decade, a minimum SS of 63.271 mV/dec and a minimum DIBL of 26.172 mV/V, respectively. The lesser the SS, the faster will be the device; hence the proposed structure can be considered as the finest prospect for VLSI/ULSI electronic chips. [ABSTRACT FROM AUTHOR]

The high energy neutron generation facilities worldwide uses the Li(p,n) system for production of the quasi mono-energetic neutrons from epithermal to few hundreds of MeV. Among the facilities either self-standing thick Li target or Li foil supported on a target assembly is used. In case of a supported Li target, either low or high mass supporting substrates like Al, C, Au, Ta etc. can be used. However, the neutron emission from the supporting substrate can interfere with the Li(p,n) reaction neutrons. In the present study neutron yields from a thin natural Li target supported on the thick natural Ta (high Z) and C (low Z) targets were measured at incident proton energies between 8-20 MeV. The proton irradiation of targets were performed at the Pelletron accelerator Facility, Mumbai and the emitted neutrons were measures at both forward (0°) and lateral (90°) directions with respect to the incident beam. The neutron yield was estimated using the CR-39 detectors and dual scintillator based active neutron spectrometer. A neutron dose equivalent (NDE) meter was also used to measure the neutron ambient dose equivalent at the measurement point. Experimentally measured neutron yields and ambient neutron dose equivalent estimates indicated higher Li(p,n) neutron yield with carbon as the supporting substrate. This is due to fewer self-emissions from natC compared to natTa target. Carbon supporting substrate also ensures improved spectral features of the Li(p,n) emission neutrons and lesser neutron fluence around the source location. This ensures efficient implementation of radiation protection practices with carbon target due to lower neutron fluence around the source compared to tantalum target. Carbon is a favorable supporting substrate compared to high Z-metal targets like Ta for emission neutron studies on Li target at proton energies between 8-20 MeV. [ABSTRACT FROM AUTHOR]

natLi(p, n) reaction is a versatile system for the generation of quasi mono-energetic neutrons from epithermal to few hundreds of MeV. The mono-energetic epithermal neutrons serve as a promising alternative source for boron-neutron capture therapy applications for cancer treatment, whereas the high energy reference neutron fields are used as calibration source for high energy physics instrumentations. However, the quasi mono-energetic nature gets disturbed at incident proton energies between 5 and 20 MeV, where different de-excitation modes contribute to the neutron emissions. So, the emission neutron studies at this intermediate proton energy range have not been covered extensively. The present work focuses on the estimation of the relative fraction of different emission neutron groups, along with the neutron spectra and angular distributions for incident proton energies between 8 and 20 MeV. The contribution of different emission neutron groups from natLi(p, n) system were calculated using the nuclear reaction model code TALYS and with FLUKA simulations. The results were validated with experimental measurements. The ambient dose equivalents were also estimated from the spectra using the ICRP-116 dose conversion coefficients and compared with the estimates obtained from a neutron dose equivalent meter. [ABSTRACT FROM AUTHOR]

In this work, electron induced modifications on the bulk etch rate, structural and optical parameters of CR-39 polymer were studied using gravimetric, FTIR (Fourier Transform Infrared) and UV-vis (Ultraviolet-Visible) techniques, respectively. CR-39 samples were irradiated with 10MeV electron beam for different durations to have the absorbed doses of 1, 10, 550, 5500, 16 500, and 55 000 kGy. From the FTIR analysis, the peak intensities at different bands were found to be changing with electron dose. A few peaks were observed to shift at high electron doses. From the UV-vis analysis, the optical band gaps for both direct and indirect transitions were found to be decreasing with the increase in electron dose whereas the opacity, number of carbon atoms in conjugation length, and the number of carbon atoms per cluster were found to be increasing. The bulk etch rate was observed to be increasing with the electron dose. The primary objective of this investigation was to study the response of CR-39 to high electron doses and to determine a suitable pre-irradiation condition. The results indicated that, the CR-39 pre-irradiated with electrons can have better sensitivity and thus can be potentially applied for neutron dosimetry. [ABSTRACT FROM AUTHOR]

Forty chilli germplasm collections were field screened against chilli thrips, Scirthothrips dorsalis Hood during consecutive summer seasons of 2017-18 and 2018-19 under natural infestation conditions at All India Co-ordinated Research Project on Vegetable Crops, Odisha University of Agriculture and Technology, Bhubaneswar. Observations on the population of S.dorsalis were recorded at weekly interval from the appearance of the pest to last picking of the chilli fruits during all the seasons. Further the germplasm were visually rated for infestation of S.dorsalis in 0-4 point scale based on the 'upward leaf curl' damage symptom at 45, 60, 75, 90 and 105 DAT (Days After Transplanting). Mean population of S.dorsalis and per cent leaf curl index were computed which were further pooled to get aggregate mean population and leaf curl index over two seasosns. On the basis of this aggregate mean population and per cent leaf curl index values, none of the germplasm was found in highly resistant category. The germplasm collections viz., BC-7-2-1, BC-25 were identified as resistant whereas the genotypes viz., BC-79-1, BC-27-2-2, Utkal Abha (RC), BC-21 and BC-406 were identified as moderately resistant categories. These may be further utilized as donor parents in developing the cultivars resistant to S.dorsalis. [ABSTRACT FROM AUTHOR]

A recent trend in photovoltaic technology is to aim to enhance the conversion efficiency of this energy harvesting technique. Although multijunction solar cells offer high efficiency, factors such as fabrication cost, cost per watt of energy produced, etc. limit their application. An alternative approach based on a lower-bandgap GaAs/GaSb dual-junction solar cell is proposed herein. For efficient use of longer wavelengths of the solar spectrum, a model for a simple antireflection coating (ARC)-less GaAs/GaSb dual-junction cell with a double back-surface field layer was optimized. The model was simulated using the Silvaco ATLAS technology computer-aided design (TCAD) tool and validated based on parameters such as the quantum efficiency, photogeneration rate, and spectral response. The model predicts conversion efficiency of 54%, better than some reported experimental results. [ABSTRACT FROM AUTHOR]

CR-39 detectors, widely used for neutron dosimetry in accelerator radiation environment, have also been applied in tissue microdosimetry by generating the linear energy transfer (LET) spectrum. In this work, the neutron dose has been estimated via LET spectrometry for 9Be (p, n) reaction which is useful for personnel monitoring around particle accelerators and accelerator based therapy facilities. Neutrons were generated by the interaction of protons of 6 different energies from 4-24 MeV with a thick Be target. The LET spectra were obtained from the major and minor radii of each track and the thickness of removed surface. From the LET spectra, the absorbed dose (DLET) and the dose equivalent (HLET) were estimated using Q-L relationship as given by International Commission on Radiological Protection (ICRP) 60. The track density in CR-39 detector and hence the neutron yield was found to be increasing with the increase in projectile (proton) energy. Similar observations were also obtained for absorbed dose (DLET) and dose equivalents (HLET). [ABSTRACT FROM AUTHOR]

A systematic study on the measurement of neutron spectra emitted from the interaction of protons of various energies with a thick beryllium target has been carried out. The measurements were carried out in the forward direction (at 0° with respect to the direction of protons) using CR-39 detectors. The doses were estimated using the in-house image analyzing program autoTRAK_n, which works on the principle of luminosity variation in and around the track boundaries. A total of six different proton energies starting from 4 MeV to 24 MeV with an energy gap of 4 MeV were chosen for the study of the neutron yields and the estimation of doses. Nearly, 92% of the recoil tracks developed after chemical etching were circular in nature, but the size distributions of the recoil tracks were not found to be linearly dependent on the projectile energy. The neutron yield and dose values were found to be increasing linearly with increasing projectile energies. The response of CR-39 detector was also investigated at different beam currents at two different proton energies. A linear increase of neutron yield with beam current was observed. [ABSTRACT FROM AUTHOR]

Photo-neutron production in electron accelerator near the threshold energy has been studied by Monte Carlo simulation using the FLUKA code. A pencil beam of 10 MeV electron was incident normally on W, Ta, Pb and Bi targets and a CR-39 detector attached to the target was used as scoring region. In the simulation, photon and neutron spectra, yield and their spatial distribution, fast neutron fluence above 100 keV, total dose and neutron dose deposition were estimated for these metallic targets. The photon emission was found to be forward peaked whereas the neutron emission was isotropic in nature. The photon yield was found to be 5 to 6 orders of magnitude higher than that of neutrons. In W and Ta, the photon yield is maximum for 1.5 mm thickness whereas for Pb and Bi, the photon yield is highest at 2 and 2.5 mm respectively. The total neutron yield was highest for W and lowest for Pb whereas highest number of fast neutrons above 100 keV was for W followed by Bi, Pb and Ta. Production of significant number of fast neutrons above 100 keV suggests the possibility of the use of CR-39 detector for measurement of these neutrons. The total dose deposition was found to be highest for Bi followed by Pb, Ta and W whereas the neutron dose equivalent was highest for W followed by Pb, Bi and Ta. This simulation study will be useful for neutron dosimetry, estimation of source term, implementation of CR-39 for measurement and other radiation protection aspects in the vicinity of an electron accelerator., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Effects of the duration of chemical etching on the transmittance, absorbance and optical band gap width of the CR-39 (Polyallyl diglycol carbonate) detectors irradiated to high neutron doses (12.7, 22.1, 36.0 and 43.5 Sv) were studied. The neutrons were produced by bombardment of a thick Be target with 12 MeV protons of different fluences. The unirradiated and neutron-irradiated CR-39 detectors were subjected to a stepwise chemical etching at 1h intervals. After each step, the transmission spectra of the detectors were recorded in the range from 200 to 900 nm, and the absorbances and optical band gap widths were determined. The effect of the etching on the light transmittance of unirradiated detectors was insignificant, whereas it was very significant in the case of the irradiated detectors. The dependence of the optical absorbance on the neutron dose is linear at short etching periods, but exponential at longer ones. The optical band gap narrows with increasing etching time. It is more significant for the irradiated dosimeters than for the unirradiated ones. The rate of the narrowing of the optical band gap with increasing neutron dose increases with increasing duration of the etching., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Effects of high-dose neutron irradiation on chemical and optical properties of CR-39 were studied using FTIR (Fourier Transform Infrared) and UV-vis (Ultraviolet-Visible) spectroscopy. The primary goal was to find a correlation between the neutron dose and the corresponding changes in the optical and chemical properties of CR-39 resulted from the neutron irradiation. The neutrons were produced by bombarding a thick Be target with 22-MeV protons. In the FTIR spectra, prominent absorbance peaks were observed at 1735cm(-1) (C=O stretching), 1230cm(-1)(C-O-C stretching), and 783cm(-1)(=C-H bending), the intensities of which decreased with increasing neutron dose. The optical absorbance in the visible range increased linearly with the neutron dose. Empirical relations were established to estimate neutron doses from these optical properties. This technique is particularly useful in measuring high doses, where track analysis with an optical microscope is difficult because of track overlapping., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

CR-39 detectors, widely used for neutron dosimetry in accelerator radiation environment, have also been applied in tissue microdosimetry by generating the linear energy transfer (LET) spectrum. In this work, the neutron dose has been estimated via LET spectrometry for (9)Be (p, n) reaction which is useful for personnel monitoring around particle accelerators and accelerator based therapy facilities. Neutrons were generated by the interaction of protons of 6 different energies from 4-24 MeV with a thick Be target. The LET spectra were obtained from the major and minor radii of each track and the thickness of removed surface. From the LET spectra, the absorbed dose (D LET) and the dose equivalent (H LET) were estimated using Q-L relationship as given by International Commission on Radiological Protection (ICRP) 60. The track density in CR-39 detector and hence the neutron yield was found to be increasing with the increase in projectile (proton) energy. Similar observations were also obtained for absorbed dose (D LET) and dose equivalents (H LET).

A systematic study on the measurement of neutron spectra emitted from the interaction of protons of various energies with a thick beryllium target has been carried out. The measurements were carried out in the forward direction (at 0° with respect to the direction of protons) using CR-39 detectors. The doses were estimated using the in-house image analyzing program autoTRAK_n, which works on the principle of luminosity variation in and around the track boundaries. A total of six different proton energies starting from 4 MeV to 24 MeV with an energy gap of 4 MeV were chosen for the study of the neutron yields and the estimation of doses. Nearly, 92% of the recoil tracks developed after chemical etching were circular in nature, but the size distributions of the recoil tracks were not found to be linearly dependent on the projectile energy. The neutron yield and dose values were found to be increasing linearly with increasing projectile energies. The response of CR-39 detector was also investigated at different beam currents at two different proton energies. A linear increase of neutron yield with beam current was observed.