Electrical Transport Characteristics and Deep Level Transient Spectroscopy of Ni/V/n-InP Schottky Barrier Diodes

We report on the temperature-dependent electrical characteristics and deep level transient spectroscopy (DLTS) of the Ni/V/n-InP Schottky diodes in the temperature range of 180-420 K. Current density - voltage (J-V) characteristics of these diodes have been analyzed on the basis of thermionic emission theory with Gaussian distribution model of barrier height. The calculated Schottky barrier height (bo) and ideality factor (n) of Ni/V Schottky contact is in the range of 0.39 eV and 2.36 at 180 K, and 0.69 eV and 1.27 at 420 K, respectively. It is observed that the zero-bias barrier height increases while ideality factor decreases with increasing temperature. A bo versus q/2kT plot is drawn to obtain evidence of a Gaussian distribution of the barrier heights, and values of = 0.95 eV and 0 = 128 eV for the mean barrier height and standard deviation. A modified Richardson plot gives (T=0)= 0.98 eV and Richardson constant (A*) = 7.068 A K – 2cm – 2. The discrepancy between Schottky barrier height (SBHs) estimated from J-V and C-V measurements is also discussed. Thus, it is concluded that the temperature dependence of J-V characteristics of the SBHs on n-InP can be explained on the basis of themionic emission mechanism with Gaussian distribution of the barrier heights. DLTS results showed that two deep levels are identified (E1 and E2) in as-grown sample having activation energies of 0.29 ± 0.01 and 0.69 ± 0.02 with capture cross-section 3.29 × 10 – 15 cm2 and 5.85 × 10 – 17 cm2 respectively. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2777

Electrical transport characteristics of Pd/V/N-InP Schottky diode from I-V-T and C-V-T measurements

The temperature dependence of current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the Pd/V contacts on undoped n-type InP Schottky barrier diodes (SBDs) have been systematically investigated in the temperature range of 200-400 K. The transition metal palladium (Pd) is used as a second contact layer because it has high work function, it reacts with InP at low temperatures and improved contact morphology. The ideality factor (n) and zero-bias barrier height are found to be strongly temperature dependent and while the zero-bias barrier height Φbo (I-V) increases, the ideality factor n decreases with increasing temperature. The experimental values of BH and n for the devices are calculated as 0.48 eV (I-V), 0.85 eV (C-V) and 4.87 at 200 K, 0.65 eV (I-V), 0.69 (C-V) eV and 1.58 at 400 K respectively. The I-V characteristics are analyzed on the basis of thermionic emission (TE) theory and the assumption of Gaussian distribution of barrier heights due to barrier inhomogeneities that prevail at the metal-semiconductor interface. The zero-bias barrier height Φbo versus 1/2kT plot has been drawn to obtain the evidence of a Gaussian distribution of the heights and the values of φ=0.89 eV and σ0= 145 meV for the mean barrier height and standard deviation. The conventional Richardson plot exhibits non-linearity with activation energy of 0.53 eV and the Richardson constant value of 4.25 × 10– 6 Acm– 2 K– 2. From the C-V characteristics, measured at 1 MHz the capacitance was determined to increase with increasing temperature. C-V measurements have resulted in higher barrier heights than those obtained from I-V measurements. As a result, it can be concluded that the temperature dependent characteristic parameters for Pd/V/n-InP SBDs can be successfully explained on the basis of TE mechanism with Gaussian distribution of the barrier heights. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2790

Modeling of EDM electrodes for development of LPOT turbine rotor and optimization of parameters for attenuate portioned electrode by Taguchi based Grey Relational Analysis

Launch vehicle requires high thrust during lift off. Semi-cryogenic engine using liquid oxygen (LOX) as the oxidiser and kerosene (earth storable) as the fuel, produces thrust around 2000kN. LOX is pumped by Low Pressure Oxidiser Turbo pump (LPOT) to level required for cavitation free operation of the Main Oxidiser Pump (MOP). Inconel 718, the material for LPOT turbine rotor has High strength thermal resistance (HSTS), ignition resistance and property of work hardening, which refers to strengthening of metal by plastic deformation (after the machining pass). The conventional machining processes cannot be adopted to produce complex shapes with high surface finish and accuracy. The non conventional machining technique like EDM is preferred. Due to the closed tip nature of the rotor die sinking EDM is preferred over wire EDM. The LPOT turbine has two rows of rotor blades; 100 symmetric blades and 105 asymmetric blades. The modeling of the EDM electrodes is done in CAD and the trial manufacturing of the electrodes for developing symmetric blade of turbine rotor is carried out. One of the electrode is having a section with 0.4mm thickness. The EDM parameters are optimized for attenuate/thin portioned electrode using Taguchi based Grey Relation Analysis. The most significant parameter using ANOVA is found out. Confirmation test are also performed with optimum parameter combination and an improvement of machining parameter is obtained

Dynamics of Hot QCD Matter -- Current Status and Developments

The discovery and characterization of hot and dense QCD matter, known as Quark Gluon Plasma (QGP), remains the most international collaborative effort and synergy between theorists and experimentalists in modern nuclear physics to date. The experimentalists around the world not only collect an unprecedented amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these data to unravel the mystery of this new phase of matter that filled a few microseconds old universe, just after the Big Bang. In the meantime, advancements in theoretical works and computing capability extend our wisdom about the hot-dense QCD matter and its dynamics through mathematical equations. The exchange of ideas between experimentalists and theoreticians is crucial for the progress of our knowledge. The motivation of this first conference named "HOT QCD Matter 2022" is to bring the community together to have a discourse on this topic. In this article, there are 36 sections discussing various topics in the field of relativistic heavy-ion collisions and related phenomena that cover a snapshot of the current experimental observations and theoretical progress. This article begins with the theoretical overview of relativistic spin-hydrodynamics in the presence of the external magnetic field, followed by the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized by IIT Goa & Goa University, Goa, Indi

Table_1_An evaluation of energy and carbon budgets in diverse cropping systems for sustainable diversification of rainfed uplands in India's eastern hill and plateau region.docx

With increasing cost and use of energy in agriculture, the traditional practice of mono-cropping of rice in upland is neither sustainable nor eco-friendly. It is necessary to identify crop diversification options with high energy efficiency, productivity, and low global warming potential (GWP). In this experiment, an inclusive system analysis was accomplished for 3 years (2016–2019) of five mono-cropping production (MCP) systems namely rice (R), finger millet (FM), black gram (BG), horse gram (HG), pigeon pea (PP), and four intercropped systems viz. R+BG, R+HG, FM+ BG, and FM + HG. The key objective was to evaluate the flow of energy, carbon balance, and GWP of these varied production systems. Puddled rice was recorded as an energy-exhaustive crop (27,803 MJ ha−1), while horse gram was noted to have the lowest energy use (26,537 MJ ha−1). The total energy output from pigeon pea (130,312 MJ ha−1) and diversified intercropped systems (142,135 MJ ha−1) was 65.3% and 80.3% higher than mono-cultured systems, respectively. Rice and rice-based intercropping production systems showed higher carbon footprints (1,264–1,392 kg CO2 eq. ha−1). Results showed that R+BG and R+HG were the most energy-efficient production systems, having higher energy ratio (5.8 and 6.0), higher carbon efficiency (7.41 and 8.24), and carbon sustainability index (6.41 and 7.24) as against 3.30, 3.61, and 2.61 observed under sole cropping production systems. On average, rice and rice-based production systems had 7.4 times higher GWP than other production systems. In productivity terms, pigeon pea and FM+HG had higher rice equivalent yields of 8.81 and 5.79 t ha−1 and benefit-cost ratios of 2.29 and 1.87, respectively. Thus, the present study suggests that pigeon pea and finger millet-based intercropping systems were the most appropriate crop diversification options for the rainfed upland agro-ecosystem of the eastern region of India.</p

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Not AvailableMangroves are one of the most productive coastal ecosystems, which act as natural barriers against natural calamities such as cyclones, tide upsurges and tsunamis. Mangrove ecosystems provide natural habitat for a wide variety of flora and fauna, whilst the economic contribution by mangroves for tourism, fisheries and other natural resources is also of paramount importance. This study focusses on the biodiversity of four major regions of Indian mangroves, namely, Bhitarkanika (Odisha), Pichavaram (Tamil Nadu), Chorao Islands (Goa) and Porlob Jig (Andaman and Nicobar Islands). The study aims to monitor the present status of mangroves in Southern and Eastern coasts of India, with the synergistic use of optical and SAR data. The aerial extents of all the Dominant vegetation spatial maps generated revealed that the Bhitarkanika mangroves had the largest extent (14425 ha) among the four mangrove regions. The second largest area recorded was by the Porlob Jig mangroves of the Andaman and Nicobar Islands (9972 ha), followed by the Pichavaram mangroves (788 ha) and the mangroves of Chorao Islands of Goa (603 ha). Decision makers, for taking the necessary conservation and management actions to protect these fragile, vital habitats can ultimately use this data. • Key policy insights • This paper provides an insight into the major mangrove species of India. It gives a detailed account of the varying mangrove biodiversity in the Eastern and Western coast of India. The prevalence of various kinds of mangroves from different ecosystems were documented. Among these, Rhizophora annamalayana specious was found indigenously in Tamil Nadu.Not Availabl

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Not AvailableMangroves are one of the most productive coastal ecosystems, which act as natural barriers against natural calamities such as cyclones, tide upsurges and tsunamis. Mangrove ecosystems provide natural habitat for a wide variety of flora and fauna, whilst the economic contribution by mangroves for tourism, fisheries and other natural resources is also of paramount importance. This study focusses on the biodiversity of four major regions of Indian mangroves, namely, Bhitarkanika (Odisha), Pichavaram (Tamil Nadu), Chorao Islands (Goa) and Porlob Jig (Andaman and Nicobar Islands). The study aims to monitor the present status of mangroves in Southern and Eastern coasts of India, with the synergistic use of optical and SAR data. The aerial extents of all the Dominant vegetation spatial maps generated revealed that the Bhitarkanika mangroves had the largest extent (14425 ha) among the four mangrove regions. The second largest area recorded was by the Porlob Jig mangroves of the Andaman and Nicobar Islands (9972 ha), followed by the Pichavaram mangroves (788 ha) and the mangroves of Chorao Islands of Goa (603 ha). Decision makers, for taking the necessary conservation and management actions to protect these fragile, vital habitats can ultimately use this data.Not Availabl