Indian Institute of Technology Guwahati

About: Indian Institute of Technology Guwahati is a education organization based out in Guwahati, Assam, India. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 6933 authors who have published 17102 publications receiving 257351 citations.

Observation of X(3872)→J/ψγ and search for X(3872)→ψ'γ in B decays.

Abstract: We report a study of B→(J/ψγ)K and B→(ψ'γ)K decay modes using 772×10⁶ B B events collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We observe X(3872)→J/ψγ and report the first evidence for χ(c2)→J/ψγ in B→(X_{c cγ)K decays, while in a search for X(3872)→ψ'γ no significant signal is found. We measure the branching fractions, B(B(±)→X(3872)K(±))B(X(3872)→J/ψγ)=(1.78(-0.44)(+0.48)±0.12)×10(-6), B(B(±)→χ(c2)K(±))=(1.11(-0.34)(+0.36)±0.09)×10(-5), B(B(±)→X(3872)K(±))B(X(3872)→ψ'γ)<3.45×10⁶ (upper limit at 90% C.L.), and also provide upper limits for other searches.

New quaternary half-metallic ferromagnets with large Curie temperatures

Abstract: New magnetic materials with high Curie temperatures for spintronic applications are perpetually sought for. In this paper, we present an ab initio study of the structural, electronic and magnetic p ...

Integral backstepping sliding mode control for underactuated systems: swing-up and stabilization of the Cart-Pendulum System.

Abstract: In this paper an integral backstepping sliding mode controller is proposed for controlling underactuated systems. A feedback control law is designed based on backstepping algorithm and a sliding surface is introduced in the final stage of the algorithm. The backstepping algorithm makes the controller immune to matched and mismatched uncertainties and the sliding mode control provides robustness. The proposed controller ensures asymptotic stability. The effectiveness of the proposed controller is compared against a coupled sliding mode controller for swing-up and stabilization of the Cart–Pendulum System. Simulation results show that the proposed integral backstepping sliding mode controller is able to reject both matched and mismatched uncertainties with a chattering free control law, while utilizing less control effort than the sliding mode controller.

A thiadiazole-functionalized Zr(IV)-based metal–organic framework as a highly fluorescent probe for the selective detection of picric acid

Abstract: A new, strongly luminescent Zr(IV)-based metal–organic framework (MOF) material (1) having a UiO-68 (UiO = University of Oslo) framework topology and incorporating the π-conjugated, thiadiazole-functionalized H2BTDB {H2BTDB = 4,4′-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid} ligand was synthesized under solvothermal conditions (150 °C, 24 h) using ZrCl4 and the H2BTDB ligand in DMF (DMF = N,N-dimethylformamide). The phase-purity of as-synthesized 1 was ascertained by X-ray powder diffraction (XRPD) analysis, Fourier transform infrared (FT-IR) spectroscopy and elemental analysis. Based on the thermogravimetric analyses, 1 is thermally stable up to 400 °C. XRPD experiments verify that activated 1′ retains its crystallinity when exposed to water, acetic acid and 1 M HCl solutions. As revealed by the steady-state fluorescence titration experiments, the thermally activated form of the compound (1′) showed a selective sensing behaviour towards 2,4,6-trinitrophenol (TNP, commonly known as picric acid), even in the presence of other potentially competing nitroaromatic explosive compounds. The estimated detection limit of 1′ for sensing TNP in methanol suspension was found to be 1.63 × 10−6 M. The highest fluorescence quenching ability of TNP can be attributed to both energy and electron transfer processes as well as electrostatic interactions between the hydroxyl group of TNP and the Lewis basic N-donor sites of the BTDB ligand. Endowed with its excellent detection efficiency, 1′ is a promising luminescent sensor material for the long-term, practical sensing of TNP.