Wannier90 is an open-source computer program for calculating maximally-localised Wannier functions (MLWFs) from a set of Bloch states. It is interfaced to many widely used electronicstructure codes thanks to its independence from the basis sets representing these Bloch states. In the past few years the development of Wannier90 has transitioned to a community-driven model; this has resulted in a number of new developments that have been recently released in Wannier90 v3.0. In this article we describe these new functionalities, that include the implementation of new features for wannierisation and disentanglement (symmetry-adapted Wannier functions, selectivelylocalised Wannier functions, selected columns of the density matrix) and the ability to calculate new properties (shift currents and Berry-curvature dipole, and a new interface to many-body perturbation theory); performance improvements, including parallelisation of the core code; enhancements in functionality (support for spinor-valued Wannier functions, more accurate methods to interpolate quantities in the Brillouin zone); improved usability (improved plotting routines, integration with arXiv:1907.09788v1 [cond-mat.mtrl-sci]

We report the performance of two new laser dyes, Pyrromethene 580 and 597, in a 10-Hz, Nd:YAG-pumped dye-laser system. These dyes demonstrate broader and more efficient tuning curves compared with those of Rhodamine 590 and 610. Pyrromethene 580 and 597 provide peak conversion efficiencies of 38% at 552 nm and 32% at 571 nm, respectively. Moreover, these new dyes provide conversion efficiencies of 31% near 572.5 nm, a wavelength used for fluorescence studies of NO. This enhanced efficiency should improve the signal-to-noise ratio in linear fluorescence [NO] measurements.

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The tribological enhancement of nano-lubricant that consist of formulated Eichhornia Crassipes carbon nanotubes (EC-CNTs) dispersed in base rapeseed oil using sodium dodecyl sulfate (SDS) and oleic acid (OA) as surfactants was conducted in this study. The experiment was done using high frequency reciprocating rig, applying 0.5 mass%, 1 mass% and 1.5 mass% EC-CNTs alongside 2% and 5% of the various surfactants and sonicated for 25 minutes and 50 minutes respectively. The use of surfactants and sonication was to reduce agglomeration. The outcome showed that SDS yielded better results than OA, further revealed that the use of 2% SDS under sonication time of 50 minutes reduced the solution agglomeration compared to 5% SDS and sonication time of 25 minutes. The tribological test conducted on EC-CNTs concentration effects was based on friction and wear reduction, load carrying ability, lubricant film stability, wear scar micrograph and mechanism of particles. The results indicated that inclusion of nanoparticles substantially enhanced the tribological characteristics. However, pronounced enhancement was recorded with 1 mass% EC-CNT compared to counterpart lubricants. Friction and wear reduction by 1 mass% EC-CNT were 65.4% and 63.6% respectively against base oil. The nanoparticles exhibited excellent mechanism for which the tribological enhancement was achieved.