Abrasion, Erosion and Cavitation Erosion Wear Properties of Thermally Sprayed Alumina Based Coatings

Thermally-sprayed alumina based materials, e.g., alumina-titania (Al2O3-TiO2), are commonly applied as wear resistant coatings in industrial applications. Properties of the coatings depend on the spray process, powder morphology, and chemical composition of the powder. In this study, wear resistant coatings from Al2O3 and Al2O3-13TiO2 powders were sprayed with plasma and high-velocity oxygen-fuel (HVOF) spray processes. Both, fused and crushed, and agglomerated and sintered Al2O3-13TiO2 powders were studied and compared to pure Al2O3. The coatings were tested for abrasion, erosion, and cavitation resistances in order to study the effect of the coating structure on the wear behavior. Improved coating properties were achieved when agglomerated and sintered nanostructured Al2O3-13TiO2 powder was used in plasma spraying. Coatings with the highest wear resistance in all tests were produced by HVOF spraying from fused and crushed powders

Fenologia de Syagrus coronata (Arecaceae) e o impacto do fogo na sobrevivência e reprodução do licuri

Three years of reproductive phenological data (1983–1986) were analyzed for 331 licuri palms (Syagrus coronata) in a natural population in Feira de Santana, Bahia, Brazil. Using a one-year subset of the data, we also compared the phenologies of 83 individuals burned by wildfires and 248 unburned individuals to examine the impact of fire on S. coronata. Burned specimens showed slightly delayed fruiting compared to non-burned specimens, but a randomization test showed no significant difference between the two groups, suggesting that licuri palms are capable of surviving wildfires with almost no interruption to their phenological cycles.Foram analisados três anos (1983–1986) de dados de fenología reprodutiva para 331 palmeiras de licuri (Syagrus coronata) numa população natural em Feira de Santana, Bahia, Brasil. Usando um subconjunto dos dados de um ano dessas populações, foi comparada a fenologia de 83 indivíduos que foram queimados com a de 248 indivíduos que não foram queimados a fim de avaliar o impacto dos incêndios na fenologia de S. coronata. Indivíduos que foram queimados apresentaram uma frutificação ligeiramente tardia em comparação aos indivíduos que não foram queimados, mas uma avaliação randomizada revelou que não há diferença significativa entre os dois grupos, sugerindo que os licuris sejam capazes de sobreviver a incêndios florestais quase sem interrupção de seus ciclos fenológicos

Floristic and structural comparisons among palm communities in primary and secondary forest fragments of the Raimundo Irineu Serra Environmental Protection Area - Rio Branco, Acre, Brazil

This study compares the composition and structure of palm communities in fragments of secondary and primary forest within the Raimundo Irineu Serra Environmental Protection Area (APARIS), located at the urban perimeter of Rio Branco, Acre. To evaluate the palm communities, we selected secondary forest areas belonging to three distinct successional stages: 7.5 years; 27.5 years, 37.5 years, and a primary forest fragment. In each forest type we installed five 20 x 20 m plots, where we analyzed floristic composition, vegetation structure, and population demography of all palm species (Arecaceae). In all, we identified 1034 palm individuals, including 12 genera, 19 species. Primary forest exhibited the greatest palm diversity. Structural analysis of each area revealed a scarcity of seedlings (≤ 50 cm tall) and reproductive adults. Fragmentation altered the composition and decreased the richness and diversity of palms within the APARIS, while at the same time, favoring the dominance of certain species, such as A. phalerata.O presente estudo compara a composição e estrutura das comunidades de palmeiras da Área de Proteção Ambiental Raimundo Irineu Serra - APARIS, localizada no perímetro urbano do Município de Rio Branco-Acre. Foram selecionadas três áreas de floresta secundária em estágios sucessionais distintos7,5 anos, 27,5 anos, 37,5 anos de idade, e um fragmento de floresta primária. Em cada área foram instaladas cinco parcelas de 20 X 20m, onde foram analisadas a composição florística, estrutura horizontal e estrutura populacional das palmeiras. Foram identificados 1.034 indivíduos, incluídos em 12 gêneros e 19 espécies de palmeiras. A área de floresta primária apresentou maior diversidade. Na análise da estrutura populacional de cada área, comprovamos a existência de uma escassez de plântulas (≤ 50 cm de altura) e adultos reprodutivos. A fragmentação alterou a composição e diminuiu a riqueza e a diversidade de palmeiras na área da APARIS, enquanto, está favorecendo a dominância de certas espécies como A. phalerata

A LCT pegmatite spectral library of the aldeia spodumene deposit: contributes to mineral exploration

Several methodologies can be employed in the prospection of Lithium (Li) in hard-rock (pegmatites). Spectrometry analysis, a Remote Sensing (RS) technique, can be applied to understand the surface spectral response of a sample, both to identify the rock-forming or alteration minerals in its composition and to validate the data collected in situ (by sensors onboard satellites/drones, for example). This paper aims to make available for public use the information acquired on the spectral composition of rock samples from the Barroso pegmatite field in Portugal, within the scope of the INOVMINERAL4.0 project. As a result, a spectral library was created with 47 spectra, collected from 11 different samples. All data is made available in a universal format, thus contributing to open science, corroborating the validation of local spectral data, and stimulating the creation of other databases, in other locations.The authors acknowledge the support provided by Portuguese National Funds through the FCT – Fundação para a Ciência e a Tecnologia, I.P. (Portugal) projects UIDB/04683/2020 and UIDP/04683/2020 (Institute of Earth Sciences); through ANI and COMPETE 2020 as well as European funds through the European Regional Development Fund (ERDF) with POCI-01-0247-FEDER- 046083 INOVMINERAL project. The authors also thank Savannah Resources PLC for access to the Aldeia pegmatite and for providing the samples used in this study. Cátia Rodrigues de Almeida and Douglas Santos were financially supported by Portuguese national funds through FCT (Grant: PRT/BD/153518/2021, Grant: UI/BD/154412/2023, respectively).info:eu-repo/semantics/publishedVersio

Deceptive Manipulation of Competitive Starting Strategies Influences Subsequent Pacing, Physiological Status, and Perceptual Responses during Cycling Time Trials

The provision of performance-related feedback during exercise is acknowledged as an influential external cue used to inform pacing decisions. The provision of this feedback in a challenging or deceptive context allows research to explore how feedback can be used to improve performance and influence perceptual responses. However, the effects of deception on both acute and residual responses have yet to be explored, despite potential application for performance enhancement. Therefore, this study investigated the effects of challenging and deceptive feedback on perceptual responses and performance in self-paced cycling time trials (TT) and explored whether changes in performance are sustained in a subsequent TT following the disclosure of the deception. Seventeen trained male cyclists were assigned to either an accurate or deceptive feedback group and performed four 16.1 km cycling TTs; 1 and 2) ride-alone baseline TTs where a fastest baseline (FBL) performance was identified, 3) a TT against a virtual avatar representing 102% of their FBL performance (PACER), and 4) a subsequent ride-alone TT (SUB). The deception group, however, were initially informed that the avatar accurately represented their FBL, but prior to SUB were correctly informed of the nature of the avatar. Affect, self-efficacy and RPE were measured every quartile. Both groups performed PACER faster than FBL and SUB (p < 0.05) and experienced lower affect (p = 0.016), lower self-efficacy (p = 0.011), and higher RPE (p < 0.001) in PACER than FBL. No significant differences were found between FBL and SUB for any variable. The presence of the pacer rather than the manipulation of performance beliefs acutely facilitates TT performance and perceptual responses. Revealing that athletes’ performance beliefs were falsely negative due to deceptive feedback provision has no effect on subsequent perceptions or performance. A single experiential exposure may not be sufficient to produce meaningful changes in the performance beliefs of trained individuals beyond the acute setting

Estimating the redshift distribution of photometric galaxy samples – II. Applications and tests of a new method

In Lima et al. we presented a new method for estimating the redshift distribution, N ( z ) , of a photometric galaxy sample, using photometric observables and weighted sampling from a spectroscopic subsample of the data. In this paper, we extend this method and explore various applications of it, using both simulations and real data from the Sloan Digital Sky Survey (SDSS). In addition to estimating the redshift distribution for an entire sample, the weighting method enables accurate estimates of the redshift probability distribution, p ( z ) , for each galaxy in a photometric sample. Use of p ( z ) in cosmological analyses can substantially reduce biases associated with traditional photometric redshifts, in which a single redshift estimate is associated with each galaxy. The weighting procedure also naturally indicates which galaxies in the photometric sample are expected to have accurate redshift estimates, namely those that lie in regions of photometric-observable space that are well sampled by the spectroscopic subsample. In addition to providing a method that has some advantages over standard photo- z estimates, the weights method can also be used in conjunction with photo- z estimates e.g. by providing improved estimation of N ( z ) via deconvolution of N ( z phot ) and improved estimates of photo- z scatter and bias. We present a publicly available p ( z ) catalogue for ∼78 million SDSS DR7 galaxies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75507/1/j.1365-2966.2009.14908.x.pd

Quasar accretion disk sizes from continuum reverberation mapping in the DES standard-star fields

Measurements of the physical properties of accretion disks in active galactic nuclei are important for better understanding the growth and evolution of supermassive black holes. We present the accretion disk sizes of 22 quasars from continuum reverberation mapping with data from the Dark Energy Survey (DES) standard star fields and the supernova C fields. We construct continuum lightcurves with the \textit{griz} photometry that span five seasons of DES observations. These data sample the time variability of the quasars with a cadence as short as one day, which corresponds to a rest frame cadence that is a factor of a few higher than most previous work. We derive time lags between bands with both JAVELIN and the interpolated cross-correlation function method, and fit for accretion disk sizes using the JAVELIN Thin Disk model. These new measurements include disks around black holes with masses as small as $\sim10^7$ $M_{\odot}$, which have equivalent sizes at 2500\AA \, as small as $\sim 0.1$ light days in the rest frame. We find that most objects have accretion disk sizes consistent with the prediction of the standard thin disk model when we take disk variability into account. We have also simulated the expected yield of accretion disk measurements under various observational scenarios for the Large Synoptic Survey Telescope Deep Drilling Fields. We find that the number of disk measurements would increase significantly if the default cadence is changed from three days to two days or one day.Comment: 33 pages, 24 figure

A socio-environmental geodatabase for integrative research in the transboundary Rio Grande/Río Bravo basin

Integrative research on water resources requires a wide range of socio-environmental datasets to better understand human-water interactions and inform decision-making. However, in transboundary watersheds, integrating cross-disciplinary and multinational datasets is a daunting task due to the disparity of data sources and the inconsistencies in data format, content, resolution, and language. This paper introduces a socio-environmental geodatabase that transcends political and disciplinary boundaries in the Rio Grande/Río Bravo basin (RGB). The geodatabase aggregates 145 GIS data layers on five main themes: (i) Water & Land Governance, (ii) Hydrology, (iii) Water Use & Hydraulic Infrastructures, (iv) Socio-Economics, and (v) Biophysical Environment. Datasets were primarily collected from public open-access data sources, processed with ArcGIS, and documented through the FGCD metadata standard. By synthesizing a broad array of datasets and mapping public and private water governance, we expect to advance interdisciplinary research in the RGB, provide a replicable approach to dataset compilation for transboundary watersheds, and ultimately foster transboundary collaboration for sustainable resource management.The project was funded by Grant No. G15AP00132 from the United States Geological Survey. Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye