Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

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IIT Palakkad

The present work describes the evolution of microstructure and enhancement of mechanical properties of friction stir welded AA6061/SiC/FA Hybrid AMCs (HAMCs). Various joints were produced using different traverse speed from 30 mm/min to 80 mm/min. Microstructural analysis was carried out using Optical microscopy and scanning electron microscopy. Mechanical characteristics such as ultimate tensile strength (UTS) and microhardness (Hv) were studied. Sound quality joints were obtained by FSW without any defects. Results showed that the microstructure zones are divided in to nugget zone, thermomechanically affected zone, heat affected zone and base material zone. Uniform and fine grain formation took place at traverse speed of 60 mm/min indicating sufficient amount of heat input at this speed. Accordingly maximum joint efficiency of 90% is obtained at this traverse speed. © 2020 Elsevier Ltd. All rights reserved.

World University root node

Department of Mechanical Engineering

Materials Today: Proceedings

Effect of traverse speed on joint characteristics of FSWed HAMCs

Cryogenic diamond burnishing is an impactful method to enhance the functional performance of the product. In this article, an experimental study on the diamond burnishing of 17-4 precipitation hardenable stainless steel in a cryogenic cooling condition has been presented. This material has excellent corrosion resistance, high strength and enormous applications in the manufacturing industries. The control variables were namely burnishing force, burnishing feed and burnishing force have been studied and modeled for the output responses explicitly surface hardness and surface roughness. The influence of control variables on performance features has been analyzed using response surface graphs. The significant influence of burnishing conditions on the output responses was established by analysis of variance. Desirability function approach has been employed to optimize the multi-performance characteristics. At the corresponding highest desirability, the optimal process parameter combination was found to be burnishing feed = 0.053 mm/rev, burnishing speed = 31.29 m/min and burnishing force = 200 N which yields a minimum surface roughness = 0.199 µm and maximum surface hardness = 397.48 HV. The maximum percentage of error among the predicted and experimental results was found to be 10% and 2%, respectively, for surface roughness and surface hardness. The investigational findings were observed to be in agreement with the predicted value with permissible deviation. © 2020, King Fahd University of Petroleum & Minerals.

Arabian Journal for Science and Engineering

Application of Desirability Approach to Optimize the Control Factors in Cryogenic Diamond Burnishing

Let H1, H2 be complex Hilbert spaces and T be a densely defined closed linear operator from its domain D(T), a dense subspace of H1, into H2. Let N(T) denote the null space of T and R(T) denote the range of T. Recall that C(T):= D(T) ∩ N(T)⊥ is called the carrier space of T and the reduced minimum modulus γ(T) of T is defined as: γ (T) : = inf{ ‖ T(x) ‖ : x∈ C(T) , ‖ x‖ = 1 }. Further, we say that T attains its reduced minimum modulus if there exists x0 ∈ C(T) such that ∥x0∥ = 1 and ∥T(x0)∥ = γ(T). We discuss some properties of operators that attain reduced minimum modulus. In particular, the following results are proved.1.The operator T attains its reduced minimum modulus if and only if its Moore-Penrose inverse T† is bounded and attains its norm, that is, there exists y0 ∈ H2 such that ∥y0∥ = 1 and ∥T†∥ = ∥T†(y0)∥.2.For each ϵ &gt; 0, there exists a bounded operator S such that ∥S∥ ≤ ϵ and T + S attains its reduced minimum. © 2020, Indian National Science Academy.

Department of Mathematics

Fulltext

Indian Journal of Pure and Applied Mathematics

Operators that Attain Reduced Minimum

We investigate the performance of niobium nitride superconducting coplanar waveguide resonators toward realizing hybrid quantum devices with magnon-photon coupling. We find internal quality factors ∼ 20 000 at 20 mK base temperature, in zero magnetic field. We find that by reducing film thickness below 100 nm, an internal quality factor greater than 1000 can be maintained up to a parallel magnetic field of ∼1 T and a perpendicular magnetic field of ∼100 mT. We further demonstrate strong coupling of microwave photons in these resonators with magnons in chromium trichloride, a van der Waals antiferromagnet, which shows that these cavities serve as a good platform for studying magnon-photon coupling in 2D magnonics based hybrid quantum systems. We demonstrate strong magnon-photon coupling for both optical and acoustic magnon modes of an antiferromagnet. © 2020 Author(s).

Department of Physics

Applied Physics Letters

Coplanar cavity for strong coupling between photons and magnons in van der Waals antiferromagnet

We investigate the patterns in distributions of localizable entanglement over a pair of qubits for random multiqubit pure states. We observe that the mean of localizable entanglement increases gradually with increasing the number of qubits of random pure states while the standard deviation of the distribution decreases. The effects on the distributions, when the random pure multiqubit states are subjected to local as well as global noisy channels, are also investigated. Unlike the noiseless scenario, the average value of the localizable entanglement remains almost constant with the increase in the number of parties for a fixed value of noise parameter. We also find that the maximum strength of noise under which entanglement survives can be independent of the localizable entanglement content of the initial random pure states. © 2020 American Physical Society.

Physical Review A

Uniform decoherence effect on localizable entanglement in random multiqubit pure states

Topological quantum error correcting codes have emerged as leading candidates towards the goal of achieving large-scale fault-tolerant quantum computers. However, quantifying entanglement in these systems of large size in the presence of noise is a challenging task. In this paper, we provide two different prescriptions to characterize noisy stabilizer states, including the surface and the color codes, in terms of localizable entanglement over a subset of qubits. In one approach, we exploit appropriately constructed entanglement witness operators to estimate a witness-based lower bound of localizable entanglement, which is directly accessible in experiments. In the other recipe, we use graph states that are local unitary equivalent to the stabilizer state to determine a computable measurement-based lower bound of localizable entanglement. If used experimentally, this translates to a lower bound of localizable entanglement obtained from single-qubit measurements in specific bases to be performed on the qubits outside the subsystem of interest. Towards computing these lower bounds, we discuss in detail the methodology of obtaining a local unitary equivalent graph state from a stabilizer state, which includes a new and scalable geometric recipe as well as an algebraic method that applies to general stabilizer states of arbitrary size. Moreover, as a crucial step of the latter recipe, we develop a scalable graph-transformation algorithm that creates a link between two specific nodes in a graph using a sequence of local complementation operations. We develop open-source Python packages for these transformations, and illustrate the methodology by applying it to a noisy topological color code, and study how the witness and measurement-based lower bounds of localizable entanglement varies with the distance between the chosen qubits. © 2020 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft.

New Journal of Physics

Scalable characterization of localizable entanglement in noisy topological quantum codes

The late-stage diversification (LSD) of structurally complex peptides has emerged as a powerful platform for molecular engineering and drug discovery. Besides traditional peptide modifications, such as native chemical ligations or cross-couplings with prefunctionalized substrates, during recent years, C―H activation has gained considerable momentum as a robust and step-economical strategy for late-stage peptide modifications, thus far predominantly for the formation of C―C bonds. Although C―N bond formations represent established strategies in medicinal chemistry and drug discovery, methods for direct amidations of tryptophan and tryptophan-containing peptides are rare and severely limited to the activated C2 position. In contrast, we herein disclose the first example of direct late-stage peptide C―H amidation reaction and the unprecedented late-stage peptide diversification on tryptophan C7 position in a highly site-selective manner. Moreover, this strategy sets the stage for sequential double C(7)―H/C(2)―H modifications, further improving the peptide structural complexity. © 2020 Elsevier Inc. Peptides represent biopolymers of key relevance to biochemistry, medicinal chemistry, natural product synthesis, and pharmaceutical industries, among others. Traditional peptide syntheses thus far largely relied on lengthy functional group interconversions. Resource-economic C–H activation has surfaced as a transformative platform for peptide modifications but continues to be restricted to tryptophan modifications at the C2-position. In sharp contrast, C7-selective peptide modifications have now been realized by versatile rhodium catalysis. The catalyzed C–H amidations occurred with outstanding levels of C7 site selectivity on highly functionalized peptides. These findings unravel the unique potential of biorthogonal late-stage diversification for the direct assembly of structurally complex peptides for biology, molecular syntheses, and drug discovery. © 2020 Elsevier Inc. Herein, we disclose the first late-stage peptide C–H nitrogenations through unprecedented rhodium(III)-catalyzed peptide C7 diversification. Thus, peptides were directly transformed through position-selective C7 amidations with easily accessible 1,4,2-dioxazol-5-ones. Structurally complex peptides featuring a wealth of functional groups underwent C7-C–H amidations to deliver selectively modified natural product and drug hybrids. © 2020 Elsevier Inc.

Department of Chemistry

Chem

Peptide Late-Stage Diversifications by Rhodium-Catalyzed Tryptophan C7 Amidation

The catalytic generation of hypervalent iodine(III) reagents by anodic electrooxidation was orchestrated towards an unprecedented electrocatalytic C−H oxygenation of weakly coordinating aromatic amides and ketones. Thus, catalytic quantities of iodoarenes in concert with catalytic amounts of ruthenium(II) complexes set the stage for versatile C−H activations with ample scope and high functional group tolerance. Detailed mechanistic studies by experiment and computation substantiate the role of the iodoarene as the electrochemically relevant species towards C−H oxygenations with electricity as a sustainable oxidant and molecular hydrogen as the sole by-product. para-Selective C−H oxygenations likewise proved viable in the absence of directing groups. © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Angewandte Chemie - International Edition

C−H Oxygenation Reactions Enabled by Dual Catalysis with Electrogenerated Hypervalent Iodine Species and Ruthenium Complexes

We disclose the unprecedented hybrid-ruthenium catalysis for distal meta-C−H activation. The hybrid-ruthenium catalyst was recyclable, as was proven by various heterogeneity tests, and fully characterized with various microscopic and spectroscopic techniques, highlighting the physical and chemical stability. Thereby, the hybrid-ruthenium catalysis proved broadly applicable for meta-C−H alkylations of among others purine-based nucleosides and natural product conjugates. Additionally, its versatility was further reflected by meta-C−H activations through visible-light irradiation, as well as para-selective C−H activations. © 2020 The Authors. Published by Wiley-VCH GmbH

Chemistry - A European Journal

Recyclable Ruthenium Catalyst for Distal meta-C−H Activation

The current paper presents the formulation of stochastic B-spline wavelet on the interval (BSWI) based wavelet finite element method (WFEM) for beams wherein, the spatial variation of modulus of elasticity is modelled as a homogeneous random field. Stochastic beam element formulations based on both Euler-Bernoulli beam theory and Timoshenko beam theory are proposed. BSWI scaling functions are used for the discretization of the random field and the response statistics are obtained using the perturbation approach. Numerical examples are solved and the results from perturbation approach are compared with that obtained from Monte Carlo simulation (MCS). A parametric study is also done to understand the effect of different coefficient of variation (CV) values and correlation length parameters on the response statistics. The study concludes that the proposed BSWI WFEM based perturbation approach for beams produce accurate response statistics for values of CV less than 15%. A comparative study is carried out between the results obtained from the proposed stochastic WFEM with stochastic finite element method (SFEM) wherein the random field discretization is done using Lagrange shape functions. Furthermore, normalized computational times for the execution of perturbation approach and MCS based on WFEM are evaluated and compared with those obtained for SFEM. © 2020 Elsevier Ltd