Concrete-to-concrete bond strength. Influence of the roughness of the substrate surface

An experimental study was performed to evaluate the bond strength between two concrete layers, for different techniques for increasing the roughness of the substrate surface. In a total of 25 slant shear specimens and 25 pull-off specimens the substrate surface was prepared by wire-brushing; sand-blasting; chipping with a light jackhammer; or were left as-cast against steel formwork. Three months later, the new concrete was added. Pull-off tests were performed to evaluate the bond strength in tension. Slant shear tests were conducted to quantify the bond strength in shear. Analysis of results indicated that: the highest value of bond strength was achieved with sand-blasting; pull-off tests are adequate to estimate the bond strength in situ; and pre-wetting the substrate surface does not seem to influence the bond strength.http://www.sciencedirect.com/science/article/B6V2G-4CMYMDN-3/1/b64e1833c354a3d441d24c410cb979d

Range maps and checklists provide similar estimates of taxonomic and phylogenetic alpha diversity, but less so for beta diversity, of Brazilian Atlantic Forest anurans

AbstractMacroecological and biogeographical studies have assumed that range map data should be used only at coarser grains due to false presences (errors of commission) at small grains. This has been explored using mostly species richness, underrepresenting other potentially informative biodiversity metrics. Here, we evaluated these issues by quantifying the extent to which taxonomic and phylogenetic alpha and beta diversity patterns calculated using anuran range maps at three cell sizes (1×1km, 5×5km, and 10×10km) differ from the patterns calculated based on checklists in 14 protected areas along the southern range of the Brazilian Atlantic Forest. We found that range maps and checklists generated reasonably similar spatial richness patterns in all cell sizes (r≥0.80 in all cases) and slightly weaker, but still correlated alpha phylogenetic diversity patterns (0.78≤r≤0.81). We also found that taxonomic (r≤0.76) and phylogenetic (r≤0.68) beta diversities had lower correlations than alpha spatial patterns. Therefore, range maps have value in documenting alpha biodiversity patterns, as well as beta diversity at more marginal levels, for tropical species at scales relevant to local conservation efforts

Financial compensation due to municipalities that host radioactive waste deposits

This work aims to perform calculation about the financial compensation due to municipalities where there is viability for construction of radioactive waste deposits from low and medium activity. Were used like base structure de Resolution No. 96 of August, 10, 2010, entitled “Model of Calculation For Financial Compensation to Municipalities” where are determinate those principal characteristics by the waste and deposits, such as the half-life, activity level, type of deposits (initial, intermediate or final), costs for construction and maintenance of deposits, demography, between others. The calculation was made according to the temporally or definitive storage for solids waste like personal protection equipment (gloves, shoes, masks, etc) resins and filters used in wastewater treatment, between others, from of nuclear and radioactivity facilities. There are presented some countries that do the compensation, financial or not, for some municipalities for the construction of waste deposits and in some cases, the way that occurred the negotiation between the stakeholders, in other words, the local population and the companies. Also are presented others forms of financial compensation in Brazil in consequence of activities in large scale which result in potential risk for the surrounding population and for the environment, like compensation for oil and natural gas, hydropower plants and mining. Were used on methodology the inventory of waste presented on RMBN project (Repository of Waste of Low and Medium Activity) developed by the CDTN which present the implementation of a repository for final storage to radioactive waste. With this was possible to develop a case study with the creation of four scenarios. Values were found which initially range from R$2,6 mil to R$79,8 mil for month. Finally are analyzed the possible influences which that values may have on the municipality budget revenue and som

Retrofitting Historic Buildings for Future Climatic Conditions and Consequences in Terms of Artifacts Conservation Using Hygrothermal Building Simulation

Funding Information: The first author acknowledges the FCT—Fundação para Ciência e a Tecnologia—for the financial support through the Ph.D. scholarship PD/BD/127844/2016. This work was financially supported by: UID/ECI/04708/2019- CONSTRUCT—Instituto de I&D em Estruturas e Construções funded by national funds through the FCT/MCTES (PIDDAC). The APC was funded by open access funds from Oslo Metropolitan University (OsloMet). Publisher Copyright: © 2023 by the authors.Climate change will greatly influence the world at several levels and will have consequences on the interior climate of historic buildings and artifacts conservation. Buildings are responsible for a large slice of the overall emissions, which is due both to the greenhouse gases that are released during their construction as well as the activities that are performed therewithin. One way of counteracting this trend is to design more efficient retrofit buildings and predict their behavior using simulation software, which can thoroughly assess the performance of new buildings or the impact of each retrofit measure for existing buildings. In this study, a calibrated computational model of high thermal inertia building was used to assess the performance of passive retrofits in mitigating the effects of climate change concerning artifact decay mechanisms. In addition, a methodology that aims to reduce the amount of time spent to perform these studies is also presented, in which time savings reach up to 63%.publishersversionpublishe

Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete

This work aims to study the influence of using construction and demolition waste in the replacement of coarse and fine aggregate to produce recycled aggregate concrete (RAC). A moderate compressive strength concrete made with usual fine and coarse aggregate was used as a benchmark material. Compressive and split tensile tests were performed using 120 cylindrical concrete specimens with 150 mm diameter and 300 mm length. Four-point flexural tests in reinforced beams made with conventional concrete and RAC were performed. The results obtained showed that the use of recycled fine aggregates, in both percentages of substitution investigated-50% and 100%-did not generate any deleterious influence on the values of compressive strength and split tensile strength of the RACs produced. Tin fact, the mechanical strengths of RACs produced with recycled fine aggregate were equal or higher than those from the reference concrete. The same behavior was not observed, however, when the recycled coarse aggregate was used. For this case, decreases in concrete mechanical strengths were observed, especially in compressive strength, with values around 35% lower when compared to the reference concrete. Tensile mechanical tests results confirmed the excellent behavior of all RACs made with replacement of usual fine aggregates by recycled. Bending tests performed in reinforced RAC beams had as objective to evaluate the deformation profile of the beams. The obtained results showed that RAC beams with full replacement of usual fine aggregate by the recycled aggregates have presented little changes in the global behavior, an aspect that encourages its use

The Taxonomic Revolution of New World dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae)

After almost two decades of stagnation, the taxonomy of the New World Scarabaeinae dung beetles has since 1988 been going through a period of great effervescence. In the last 35 years, 81 complete revisions and 69 supplements have been produced by 86 authors based in 15 countries, addressing the taxonomic status of 950 species. This is what we christen as the Taxonomic Revolution of New World dung beetles. We review the history and products of this revolution, explore its causes and its apparent exceptionalism among most other New World Coleoptera groups, and point to the many great challenges that still face the scarabaeine taxonomists. An aspect of interest to ecologists is the coevolution of the Taxonomic Revolution with what we call the Ecological Revolution of dung beetles, i.e., the similar expansion in ecological studies about these organisms. We argue that it has been the continuous feedback between these two simultaneous processes that has enabled each of them to exist and flourish: without the Ecological Revolution, the Taxonomic Revolution could not have existed, and vice-versa. Ecologists and taxonomists are partners in the scientific enterprise, symbionts one may say

Efeito da aplicação de produtos enológicos na eliminação de Aflatoxinas em vinho branco

As aflatoxinas, quimicamente definidas como difuranocumarinas, são metabolitos secundários produzidos principalmente pelas espécies Aspergillus flavus e Aspergillus parasiticus. O presente trabalho teve como objetivo estudar a ação de diferentes tipos de produtos enológicos na remoção de aflatoxinas (B1 e B2) presentes no vinho. A eficácia desses produtos na remoção das referidas micotoxinas foi avaliada utilizando vinho artificialmente contaminado com AFB1 e AFB2. O produto enológico que mostrou ser mais eficaz na remoção destas micotoxinas foi a bentonite, com percentagem de remoção de 100%. O caseinato de potássio também se mostrou eficaz, com percentagem de remoção na ordem dos 70 a 80%. Adicionalmente também se avaliou o impacto destes produtos enológicos sobre as características físico-químicas dos vinhos. Os resultados obtidos podem fornecer informações úteis para o sector vitivinícola, na seleção do produto enológico mais apropriado na remoção das aflatoxinas, reduzindo a toxicidade e melhorando simultaneamente a qualidade e segurança alimentar do vinho

Effect of the application of oenological products on fumonisin B2 (FB2) reduction/removal in contaminated red and white wines

ICFC 2017 - International Conference on Food Contaminants (Book of Abstracts)Fumonisins are mycotoxins produced by species of Fusarium, mainly F. verticillioides and F. proliferatum. Fumonisins have hepatotoxic and nephrotoxic effects in various animals and are also associated to human esophageal cancer [1] thus being classified by the IARC in Group 2 [2]. Chemically, fumonisins are characterized by a 19- or 20-carbon aminopolyhydroxyalkyl chain that is diesterified with propane-1,2,3-tricarboxylic acid groups [3]. Sharing a basic structure, several related groups of fumonisins have been isolated and identified (A, B, C and P). Fumonisins B (FBs) are the major forms found in most food products. Recently they were detected in grapes, musts and wines around the world. It was established an association between Aspergillus niger and the presence of FB2 in grape must and wine. WHO has recommended a maximum tolerable daily intake of 2 mg/kg of body weight to FB1, FB2 and FB3, alone or in combination [4], therefore it is important to prevent and control its occurrence, as well other mycotoxins, in wines [5]. The main objective of this work was to evaluate the ability of different oenological products on FB2 removal of white and red wines. For this purpose, ten commercial oenological fining agents (mineral, synthetic and organic - proteins of animal and vegetable origin) were studied to remove FB2 in white and red wines artificially contaminated with FB2. In addition to the FB2 removal, the effect of these products on wine physicochemical characteristics, namely, flavonoids, non-flavonoids and total phenolic compounds were evaluated. In red wine all products showed low reduction on FB2 removal, being the highest value (30%) achieved by calcium bentonite. The results obtained by the action of these products may be considered as a pioneer approach on wine FB2 reduction/removal, with relevance for wine industry, in order to select the best fining agent to reduce toxicity and consequently to improve wine quality and safety.info:eu-repo/semantics/publishedVersio

Sludge retention time impacts on polyhydroxyalkanoate productivity in uncoupled storage/growth processes

SFRH/BD/104767/2014 program ( GA 773375 ) UIDP/04378/2020 UIDB/04378/2020The process involving mixed microbial cultures (MMCs) and waste-based substrates emerged as an alternative solution to reduce the market price of polyhydroxyalkanoates (PHAs). The selection of an efficient MMC that displays a significant PHA accumulation potential and a high growth rate is considered a key factor for the MMC PHA production feasibility. This study used a pilot plant to investigate the dynamics of growth vs storage in a mixed culture fed with fermented fruit waste under uncoupled carbon and nitrogen feeding. Varying sludge retention times (SRTs) (2 and 4 d) and organic loading rates (OLRs) (from 2.6 to 14.5 gCOD.L−1.d−1) were imposed for this purpose. Results showed that, regardless of the OLR imposed, cultures selected at lower SRT grew faster and more efficiently using stored PHA. However, they had inferior specific storage rates and accumulation capacity, resulting in lower PHA productivity. Additionally, the polymer storage yield was independent of the SRT, and was directly linked with the abundance of putative PHA-storers in the MMC. The high PHA productivity (4.6 ± 0.3 g.L−1.d−1) obtained for the culture selected at 4 d of SRT was 80% above that obtained for the lower SRT tested, underlining the importance of achieving a good balance between culture growth and accumulation capacity to increase the viability of the PHA-producing process from wastes.publishersversionpublishe

VALIDATION OF A METHODOLOGY TO DEVELOP A TEST FACILITY IN REDUCED SCALE RELATED TO BORON DISPERSION IN A PRESSURIZER OF AN iPWR

The conception and the project of a 1:200 reduced scale test facility have been developed in earlier researches [1,2,3,4]. Such a facility aims to investigate boron homogenization process inside the pressurizer of an iPWR (integral PWR) by considering water mixing from this component with that coming from the reactor core. For this kind of reactor, the pressurizer is located at the top of the pressure vessel demanding the need of identifying the proper mechanisms in order to warrant an adequate homogenization for the water mixture. Once the installation of the experimental setup was concluded, its behavior has been analyzed by considering the concentration of a tracer diluted in the circulation water, whose measurements were obtained at the pressurizer outlet orifices. Two experiments representing boration(boron concentration increase)/deboration(boron concentration decrease) scenarios have been accomplished. Sample acquisition was carried out for every ten minutes during a total time equal to180 minutes. Results showed that the combination of Fractional Scaling Analysis with local Froude number consisted of an appropriate methodology to provide the reduced scale test facility parameters, inasmuch the measured concentrations from the experiments reproduced the theoretical behavior with sufficient accuracy