The Effects of Grain Size on Morphological Patterns and Land Cover Within Boreal Wildfire Residual Patches

The post-fire conditions comprise a matrix of burned, partially burned, and unburned patches that are ecologically and financially important. Studying the unburned patches helps planners assess the effectiveness of emulating natural disturbance patterns. MSPA quantifies spatial patterns in terms of their geometry and connectivity of landscape features. The morphological elements were identified for residual patches extracted from the RED-084 fire. Grain size coarsening and parameterizations were measured to find if they altered the frequency of morphologies within 10 land cover classes. Conifers and water classes were the most abundant and significantly different from other classes across most morphologies. Connectivity and transition changes had significant effects on islets and edges respectively. Edge width had a significant effect on cores, perforations, edges, and branches across all grain sizes. These findings can assist in developing a set of rules on the composition and configuration of land cover and morphologies left behind after harvesting

POPULATION DISTRIBUTION DURING THE DAY

Population distribution during the day can be defined as distribution of population in an area during the daytime hours. However, a precise definition of daytime hours is challenging given the geographic variability in the length of a day or daylight hours. The US Census Bureau used "normal business hours" as the span of time to describe daytime population. Given that Censuses typically estimates residential population, it represents a nighttime population distribution. In that respect, daytime population in an area may be broadly defined as distribution of population at times other than when they are expected to be at their residences at night which extends the duration from business hours to include the evening hours as well

2nd International Conference on Nanomaterials Science and Mechanical Engineering: book of abstracts

2nd International Conference on Nanomaterials Science and Mechanical Engineering: book of abstracts - University of Aveiro, Portugal July 9-12, 2019.publishe

The structural and optical constants of Ag2S semiconductor nanostructure in the far-infrared

Background In this paper a template-free precipitation method was used as an easy and low cost way to synthesize Ag2S semiconductor nanoparticles. The Kramers–Kronig method (K–K) and classical dispersion theory was applied to calculate the optical constants of the prepared samples, such as the reflective index n(ω) and dielectric constant ε(ω) in Far-infrared regime. Results Nanocrystalline Ag2S was synthesized by a wet chemical precipitation method. Ag2S nanoparticle was characterized by X-ray diffraction, Scanning Electron Microscopy, UV-visible, and FT-IR spectrometry. The refinement of the monoclinic β-Ag2S phase yielded a structure solution similar to the structure reported by Sadanaga and Sueno. The band gap of Ag2S nanoparticles is around 0.96 eV, which is in good agreement with previous reports for the band gap energy of Ag2S nanoparticles (0.9–1.1 eV). Conclusion The crystallite size of the synthesized particles was obtained by Hall-Williamson plot for the synthesized Ag2S nanoparticles and it was found to be 217 nm. The Far-infrared optical constants of the prepared Ag2S semiconductor nanoparticles were evaluated by means of FTIR transmittance spectra data and K–K method

In-depth behavioral study of l-Prolinium Trichloroacetate single crystal: An efficient candidate for NLO applications

AbstractOrganic compounds have constantly proved to be a proficient candidate for nonlinear optical (NLO) applications. In this respect an organic amino acid compound i.e. l-Prolinium Trichloroacetate single crystal has been synthesized and grown through slow evaporation solution growth technique. The lattice parameters obtained from single crystal X-ray diffraction were comparable with reported one. The diffraction pattern along the strain present inside the crystal was measured through powder X-ray diffraction technique. Its photoconductivity has also been observed, in which the traits of dark and photon current were recorded over a range of applied voltage. Further, birefringence was performed for the sample in which it was found that the crystal is having negative optical homogeneity character. The thermal transport parameters were calculated through photo-pyroelectric technique. Its resistance toward the laser beam was examined using laser damage threshold technique. The mechanical characteristics of the single crystal were determined on nanoscale using Oliver–Pharr method

Curating Transient Population in Urban Dynamics System

For past several decades, research efforts in population modelling has proven its efficacy in understanding the basic information about residential and commercial areas, as well as for the purposes of planning, development and improvement of the community as an eco-system. More or less, such efforts assume static nature of population distribution, in turn limited by the current ability to capture the dynamics of population change at a finer resolution of space and time. Fast forward today, more and more people are becoming mobile, traveling across borders impacting the nuts and bolts of our urban fabric. Unfortunately, our current efforts are being surpassed by the need to capture such transient population. It is becoming imperative to identify and define them, as well as measure their dynamics and interconnectedness. In this work, we intend to research urban population mobility patterns, gauge their transient nature, and extend our knowledge of their visited locations. We plan to achieve this by designing and developing novel methods and using VGI data that models and characterizes transient population dynamics

Nanoindentation and structural studies of MgO-doped congruent LiNbO3 single crystals

The mechanical properties of undoped and 2.0, 4.0 and 6.0 mol% Mg-doped LN single crystals, grown by the Czochralski technique, have been investigated using nanoindentation studies to understand the mechanical deformation behaviour as doping is increased. This has been correlated with structural investigations by powder XRD analysis and Raman spectroscopy. Powder X-ray diffraction measurements show a slight increase in the lattice parameters as the Mg content is increased in the crystal. The lattice strain developed due to the doping has been calculated by the Williamson-Hall relation. The influence of Mg incorporation on lattice vibrations was analysed using Raman spectroscopy, which indicated no shift in the peak positions with doping, and only slight variation in the intensity and width of the peaks. The grown crystals were subjected to nanoindentation and the Young's modulus and hardness values were obtained by using the Oliver-Pharr method. The results reveal the optimal doping levels of Mg which result in enhanced mechanical strength of lithium niobate single crystals.publishe

Enhancement of thermoelectric figure of merit in Bi2Se3 crystals through a necking process

The growth of good quality bulk single crystals of bismuth selenide by employing a high-temperature vertical Bridgman technique with a specially designed ampoule having a provision for a necking process is reported. Several growth experiments were performed and reproducible results were obtained. The crystal structure and lattice dimensions were confirmed by powder X-ray diffraction (PXRD), the bulk crystalline perfection was assessed using high-resolution X-ray diffractometry and the good bulk crystalline perfection with an indication of layered structure was confirmed. Transmission electron microscopy (TEM) was carried out for the grown single crystal and confirmed the layered structure. High-resolution TEM (HRTEM) was also used to further assess the crystalline perfection. The direct measurement of d spacing obtained from HRTEM imaging was found to be in good agreement with the data obtained from PXRD. The thermal behavior was examined by differential scanning calorimetry and a sharp melting was found at 983K, which revealed the purity of the bismuth selenide. The Seebeck coefficient and electrical and thermal conductivities were measured, and a thermoelectric figure of merit was calculated in order to assess the suitability of the crystal for thermoelectric applications such as refrigeration and portable power generation. Nanoindentation analysis was also performed for the first time