Exploring the role of electronic structure on photo-catalytic behavior of carbon-nitride polymorphs

A fully self-consistent density-functional theory (DFT) with improved functionals is used to provide a comprehensive account of structural, electronic, and optical properties of C$_{3}$N$_{4}$ polymorphs. Using our recently developed van Leeuwen-Baerends (vLB) corrected local-density approximation (LDA), we implemented LDA+vLB within full-potential N$^{th}$-order muffin-tin orbital (FP-NMTO) method and show that it improves structural properties and band gaps compared to semi-local functionals (LDA/GGA). We demonstrate that the LDA+vLB predicts band-structure and work-function for well-studied 2D-graphene and bulk-Si in very good agreement with experiments, and more exact hybrid functional (HSE) calculations as implemented in the Quantum-Espresso (QE) package. The structural and electronic-structure (band gap) properties of C$_{3}$N$_{4}$ polymorphs calculated using FP-NMTO-LDA+vLB is compared with more sophisticated hybrid-functional calculations. We also perform detailed investigation of photocatalytic behavior using QE-HSE method of C$_{3}$N$_{4}$ polymorphs through work-function, band (valence and conduction) position with respect to water reduction and oxidation potential. Our results show $\gamma$-C$_{3}$N$_{4}$ as the best candidate for photocatalysis among all the C$_{3}$N$_{4}$~polymorphs but it is dynamically unstable at `zero' pressure. We show that $\gamma$-C$_{3}$N$_{4}$ can be stabilized under hydrostatic-pressure, which improves its photocatalytic behavior relative to water reduction and oxidation potentials.Comment: 13 pages, 12 figures, 3 table

Simple correction to bandgap problems in IV and III–V semiconductors: an improved, local first-principles density functional theory

We report results from a fast, efficient, and first-principles full-potential Nth-order muffin-tin orbital (FP-NMTO) method combined with van Leeuwen–Baerends correction to local density exchange-correlation potential. We show that more complete and compact basis set is critical in improving the electronic and structural properties. We exemplify the self-consistent FP-NMTO calculations on group IV and III–V semiconductors. Notably, predicted bandgaps, lattice constants, and bulk moduli are in good agreement with experiments (e.g. we find for Ge 0.86 eV, 5.57 , 75 GPa versus measured 0.74 eV, 5.66 , 77.2 GPa). We also showcase its application to the electronic properties of 2-dimensional h-BN and h-SiC, again finding good agreement with experiments

'IHPBA-APHPBA clinical practice guidelines': international Delphi consensus recommendations for gallbladder cancer

BACKGROUND: The Delphi consensus study was carried out under the auspices of the International and Asia-Pacific Hepato-Pancreato-Biliary Associations (IHPBA-APHPBA) to develop practice guidelines for management of gallbladder cancer (GBC) globally. METHOD: GBC experts from 17 countries, spanning 6 continents, participated in a hybrid four-round Delphi consensus development process. The methodology involved email, online consultations, and in-person discussions. Sixty eight clinical questions (CQs) covering various domains related to GBC, were administered to the experts. A consensus recommendation was accepted only when endorsed by more than 75% of the participating experts. RESULTS: Out of the sixty experts invited initially to participate in the consensus process 45 (75%) responded to the invitation. The consensus was achieved in 92.6% (63/68) of the CQs. Consensus covers epidemiological aspects of GBC, early, incidental and advanced GBC management, definitions for radical GBC resections, the extent of liver resection, lymph node dissection, and definitions of borderline resectable and locally advanced GBC. CONCLUSIONS: This is the first international Delphi consensus on GBC. These recommendations provide uniform terminology and practical clinical guidelines on the current management of GBC. Unresolved contentious issues like borderline resectable/locally advanced GBC need to be addressed by future clinical studies

Processing-microstructure-yield strength correlation in a near β Ti alloy,Ti–5Al–5Mo–5V–3Cr

A combined set of thermo-mechanical steps recommended for high strength β Ti alloy are homogenization,deformation, recrystallization,annealing and ageing steps in sequence.Recrystallization carried out above or below β transus temperature generates either β annealed(lath type morphology of α) or bimodal (lath+globular morphology of α) microstructure.Through variations in heat treatment parameters at these processing steps,wide ranges of length scales of features have been generated in both types of microstructures in a near β Ti alloy,Ti–5Al–5Mo–5V–3Cr(Ti-5553).0.2%Yield strength(YS)has been correlated to various microstructural features and associated heat treatment parameters.Relative importance of microstructural features in influencing YS has been identified.Process parameters at different steps have been identified and recommended for attaining different levels of YS for this near β Ti alloy

Leopards in Human dominated Areas: a Spillover from Sustained Translocations Into Nearby Forests?

Volume: 104Start Page: 45End Page: 5

Simple correction to bandgap problems in IV and III–V semiconductors: an improved, local first-principles density functional theory

We report results from a fast, efficient, and first-principles full-potential Nth-order muffin-tin orbital (FP-NMTO) method combined with van Leeuwen–Baerends correction to local density exchange-correlation potential. We show that more complete and compact basis set is critical in improving the electronic and structural properties. We exemplify the self-consistent FP-NMTO calculations on group IV and III–V semiconductors. Notably, predicted bandgaps, lattice constants, and bulk moduli are in good agreement with experiments (e.g. we find for Ge 0.86 eV, 5.57 , 75 GPa versus measured 0.74 eV, 5.66 , 77.2 GPa). We also showcase its application to the electronic properties of 2-dimensional h-BN and h-SiC, again finding good agreement with experiments.</p

Simple correction to bandgap problems in IV and III–V semiconductors: an improved, local first-principles density functional theory

We report results from a fast, efficient, and first-principles full-potential Nth-order muffin-tin orbital (FP-NMTO) method combined with van Leeuwen–Baerends correction to local density exchange-correlation potential. We show that more complete and compact basis set is critical in improving the electronic and structural properties. We exemplify the self-consistent FP-NMTO calculations on group IV and III–V semiconductors. Notably, predicted bandgaps, lattice constants, and bulk moduli are in good agreement with experiments (e.g. we find for Ge 0.86 eV, 5.57 angstrom, 75 GPa versus measured 0.74 eV, 5.66 angstrom, 77.2 GPa). We also showcase its application to the electronic properties of 2-dimensional h-BN and h-SiC, again finding good agreement with experiments.This is a peer-reviewed, un-copyedited version of an article accepted for publication/published in Journal of Physics: Condensed Matter. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at 10.1088/1361-648X/ab34ad. Posted with permission.</p