Effect of actual thermo-physical properties on heat transfer and materials flow for dissimilar materials Al 6061-T6 and AZ31

by Amit Kumar Singh,Pankaj Shalot and Amit Aror

BioGen: automated biography generation

by Heer Ambavi, Ayush Garg, Nitiksha,Sharma Mridul,Rohit Sharma, Jayesh Choudhari and Mayank Sing

GPU acceleration of the KAZE image feature extraction algorithm

GPU in comparison to nearly 2400 ms for a 16-threaded CPU version) without degradation in feature extraction performance, our work expands the applicability of the KAZE algorithm. Additionally, the strategies described here could also prove useful for the GPU implementation of other nonlinear scale-space-based image processing algorithms.by B. Ramkumar, Rob Laber, Hristo Bojinov and Ravi Sadananda Hegd

Aggregation behavior of inorganic 2D nanomaterials beyond graphene: insights from molecular simulations and modified DLVO theory

We report the comparative aggregation behavior of three emerging inorganic 2D nanomaterials (NMs): MoS2, WS2, and h-BN in aquatic media. Their aqueous dispersions were subjected to aggregation under varying concentrations of monovalent (NaCl) and divalent (CaCl2) electrolytes. Moreover, Suwanee River Natural Organic Matter (SRNOM) has been used to analyze the effect of natural macromolecules on 2D NM aggregation. An increase in electrolyte concentration resulted in electrical double-layer compression of the negatively charged 2D NMs, thus displaying classical Derjaguin-Landau-Verwey-Overbeek (DLVO) type interaction. The critical coagulation concentrations (CCC) have been estimated as 37, 60, and 19 mM NaCl and 3, 7.2, and 1.3 mM CaCl2 for MoS2, WS2, and h-BN, respectively. Theoretical predictions of CCC by modified DLVO theory have been found comparable to the experimental values when dimensionality of the materials is taken into account and a molecular modeling approach was used for calculating molecular level interaction energies between individual 2D NM nanosheets. Electrostatic repulsion has been found to govern colloidal stability of MoS2 and WS2 while the van der Waals attraction has been found to govern that of h-BN. SRNOM stabilizes the 2D NMs significantly possibly by electrosteric repulsion. The presence of SRNOM completely stabilized MoS2 and WS2 at both low and high ionic strengths. While h-BN still showed appreciable aggregation in the presence of SRNOM, the aggregation rates were decreased by 2.6- and 3.7-fold at low and high ionic strengths, respectively. Overall, h-BN nanosheets will have higher aggregation potential and thus limited mobility in the natural aquatic environment when compared to MoS2 and WS2. These results can also be used to mechanistically explain fate, transport, transformation, organismal uptake, and toxicity of inorganic 2D NMs in the natural ecosystems.by Tashfia M. Mohona, Anusha Gupta, Arvid Masud, Szu-Chia Chien, Li-Chiang Lin, Prathima C. Nalam and Nirupam Aic

Branching effect on triphenylamine-CF3 cyanostilbenes: enhanced emission and aggregation in water

Six linear and branched ?-cyanostilbene derivatives bearing a triphenylamine donor and an electron withdrawing trifluoromethyl group on the phenyl ring and a cyano acceptor on the double bond were synthesized and examined for their absorption and emission properties in solution and the solid state. The molecules exhibit characteristic solvatochromic emission and aggregation induced emission in water. Interesting absorption and emission changes were observed upon branching with the third arm exerting a negligible effect. Dropcast SEM images of these molecules in water reveal unique morphological features with the formation of uniform structures. The triply branched triphenylamine forms a stable organogel aided by intermolecular interactions. The results are substantiated using DFT calculations.by Beena Kumari, Surya Pratap Singh, Ranga Santosh, Arnab Dutta, Sairam S. Mallajosyula, Subhas Ghosalc and Sriram Kanva

Mg addition in undoped and Al-doped ZnO films: Fabricating near UV transparent conductor by bandgap engineering

Developing transparent conductors that can utilize a portion of the UV range of the sunlight requires bandgap engineering by varying the process parameters as well as type and concentration of dopants in the host materials. To this end, ZnO is a desired material because of its wide direct band gap (Eg) of around 3.2 eV, low cost and less toxicity. In this work, Mg2+ and/or Al3+-doped ZnO films are prepared by varying a range of process parameters in RF magnetron sputtering. A detailed microstructural and optoelectronic characterization of all these films are then carried out by using a combination of experimental techniques, like, GIXRD, FESEM, EDS, UV–Vis–NIR, PL spectroscopy and Hall Effect measurement system. All these films are found to have high optical transparency and showed blue shift as a result of Mg2+ and/or Al3+ doping with Eg ranging from 3.24 to 3.90 eV. Moreover, (Mg2+, Al3+)-doped ZnO films are found to demonstrates better optoelectronic properties than those of the ZnO films doped only using either Mg2+ or Al3+. Whereas Mg2+ is found to increase the optical bandgap of these films, Al3+ addition is found to increase both the carrier concentration and carrier mobility, with the best values of the electrical properties being obtained when only Al3+ is added to ZnO. This study shows a possible method to harness the near UV portion of the sunlight by doing bandgap engineering of ZnO through the addition of Mg2+ and/or Al3+ without compromising much on their overall electrical properties.by Rishi Dhawan and Emila Pand

Parameterisation of auto-spectral density of earthquake induced strong ground motions

This paper explores the possibility of a new parametric representation of auto-spectral density (ASD) that enables extraction of several meaningful insights. Recorded translational ground motions are considered first and the resulting parametric model is capable to address the scenario when seismic energy is distributed over multiple frequency bands. A slightly different form is developed to address the rotational ground motion. Variation of ASD over the footprint of seismic arrays, both large (SMART1) and dense (LSST), is studied. The assessment is based on spectral similitude using spectral contrast angles and distance correlation. Possible correlation of the parameters of the proposed ASD model against site and event characteristics is investigated based on selected ground motions from PEER database. Model parameters thus computed are used in synthetically predicting the ASD of ground motions at the LSST array and that shows good resemblance against the recorded events.by Gopala Krishna Rodda and Dhiman Bas

Dipyrrinato complexes with 4d and 5d metals: synthesis, crystal structures and singlet oxygen generation studies

by Neha Manav, Anu A. and Iti Gupt

Heavy quark dynamics in a hot magnetized QCD medium

The heavy quark drag and momentum diffusion have been investigated in a hot magnetized quark-gluon plasma, along the directions parallel and perpendicular to the magnetic field. The analysis is done within the framework of Fokker-Planck dynamics by considering the heavy quark scattering with thermal quarks and gluons at the leading order in the coupling constant. An extended quasiparticle model is adopted to encode the thermal QCD medium interactions in the presence of a magnetic field. Further, the higher Landau level effects on the temperature behavior of the parallel and perpendicular components of the drag force and diffusion coefficients have studied. It has been observed that both the equation of state and the magnetic field play key roles in the temperature dependence of the heavy quark dynamics.by Manu Kurian, Santosh K. Das and Vinod Chandr

Advancement in confined masonry construction for improved seismic safety of buildings in India

by Sudhir K. Jain, Svetlana Brzev, D C. Rai and K. Mitr