Experimental study of the ageing of building stones exposed to sulfurous and nitric acid atmospheres

During the last few decades, due to remediation procedures, SO2 emissions in the atmosphere have decreased, unlike NOx. Air pollution has changed. Indeed, the aim of this research is to assess the effect of NOx and their interactions with SO2 on stones, particularly on limestones used in Champagne-Ardenne (France) during the restoration processes. Three French building limestones (Courville, Dom and Savonnières) and one reconstituted stone were exposed during 28 days to four strong acid atmospheres i.e. two H2SO3 solutions with different concentrations and two mixed atmospheres with different proportions of HNO3 and H2SO3. These tests produced an intensive acid attack on the stone, allowing the observation of short-term salt precipitation and the evolution of stone properties. Each day, one sample was removed from the acid atmosphere to measure the concentration of SO4(2-) and NO3(-) by ion-chromatography. The surface changes were assessed before and after the tests by 3D scanning and observations with electron microscopy. X-ray microtomography has been performed in the Centre for X-ray Tomography (UGCT) and the Department of Geology at Ghent University (Belgium) in order to observe the penetration of salts and the consequences in stones porosity. First observations showed that exposure to acid atmosphere, led to gypsum efflorescences. Obvious colour changes occurred in all tests. Salt crystallization entailed a change in the porous system, which was evidenced by 3D, mercury porosimetry and X-ray microtomography. Difference between weathered and fresh stone was highlighted by Ion chromatography analyses

Thermophysical characteristics of radioactive graphite - Water vapor system

The article considers thermophysical characteristics of radioactive graphite - water vapor system in temperature range 373-3273K. The research was made by thermodynamic modeling method using TERRA software. We determined 4 temperature intervals in which changes of thermophysical characteristics of radioactive graphite - water vapor system occur. © 2017 The Authors, published by EDP Sciences

Safe nights out: Workers’ perspectives on tackling violence against women and girls

Existing research focused on workers within the night-timeeconomy (NTE) is limited. In this unique study, research was conducted with workers from a wide range of professions and occupations. The study garnered important insights into NTE workers’ understanding and experience of violence against women and girls (VAWG). Workers observed a strong relationship between alcohol consumption and VAWG and were knowledgeable about spiking, perceiving this practice to be growing. Strong protocols were in place to support women when spiking was alleged. The understanding of VAWG was, in contrast, broad but inconsistent. NTE workers provide myriad ways to support and protect women who are out at night. However, responses to potential incidents of VAWG are shaped by intuition, rather than being rooted in formal knowledge and institutional protocols. The decision to intervene is usually based on NTE workers’ levels of experience, confidence, and subjective perception of risk – described as ‘going with your gut’. There were, however, some good examples of where formal training had been provided and found to be useful. Specifically,there was evidence that many of the initiatives established as part of the Safer Streets project were making a difference. Respondents valued the training that they had received (such as zero-tolerance), and they recognised the important role that Street Pastors provide. Nevertheless, several training gaps were identified. Specifically, workers reported that they wanted to be better equipped to identify potential perpetrators of crime and would welcome advice on how to enhance personal and customer safety. NTE workers would also benefit from knowing more about the location and value of safe havens. The study showed that while many venues offer support to customers, there is some inconsistency in the way that safety measures are advertised and enacted

Experimentos em riticulado quadrado com alguns tratamentos comuns adicionados em cada bloco: análise intrablocos.

Apresentou-se um metodo geral de analise intrablocos para o caso de um ensaio em reticulado quadrado aumentado pela adicao de alguns tratamentos comuns a todos os blocos. Os tratamentos do delineamento inicial foram designados de tratamentos regulares, e os adicionados aos blocos, de tratamentos comuns. Os parametros do delineamento inicial foram definidos como: k (numero de parcelas por bloco), v = k2 (numero de tratamentos regulares), b (numero de blocos), i (numero de repeticoes ortogonais), n (numero de vezes que as repeticoes ortogonais sao repetidas) e r= ni (numero de repeticoes dos tratamentos). A inclusao de c tratamentos comuns em cada bloco do experimento resultou em um delineamento aumentado, com os seguintes parametros: v' = v +c (numero total de tratamentos), b (numero de blocos), k' = k + c (numero de parcelas por bloco), r' (numero de repeticoes de cada tratamento e uu'(numero de blocos onde os tratamentos u e u' ocorrem juntos). O modelo matematico adotado foi o seguinte y uh = m + tu + bh + euh e a observacao do u-esimo tratamento no h-esimo bloco; m e a media geral; tu e o efeito do u-esimo tratamento (u= 1,2,....v'); bh e o efeito do h-esimo bloco (h = 1, 2, ...., b) e euh e o erro experimental associado a yuh onde euh (0, o2). Foram determinadas as expressoes para as varias somas de quadrados na analise de variancia, as medias de tratamentos ajustadas para blocos e a variancia da estimativa de um contraste entre duas medias de tratamentos

Multi-target prediction of wheat flour quality parameters with near infrared spectroscopy

Near Infrared (NIR) spectroscopy is an analytical technology widely used for the non-destructive characterisation of organic samples, considering both qualitative and quantitative attributes. In the present study, the combination of Multi-target (MT) prediction approaches and Machine Learning algorithms has been evaluated as an effective strategy to improve prediction performances of NIR data from wheat flour samples. Three different Multi-target approaches have been tested: Multi-target Regressor Stacking (MTRS), Ensemble of Regressor Chains (ERC) and Deep Structure for Tracking Asynchronous Regressor Stack (DSTARS). Each one of these techniques has been tested with different regression methods: Support Vector Machine (SVM), Random Forest (RF) and Linear Regression (LR), on a dataset composed of NIR spectra of bread wheat flours for the prediction of quality-related parameters. By combining all MT techniques and predictors, we obtained an improvement up to 7% in predictive performance, compared with the corresponding Single-target (ST) approaches. The results support the potential advantage of MT techniques over ST techniques for analysing NIR spectra

Aspectos do melhoramento genético do gado canchim

This paper deals with the estimation of the heritability of weight at the age of 18 months of heifers of the Canchim breed, which is a 5/3 Charolais x 3/8 Zebu crossbred. It evaluates also the bulls and cows, through the heritage transmitted to their offspring. The study was carried out with the 18-month weights of 252 heifers, sons and daughters of 15 sires and 94 cows, adjusted for sex, and for season and order of delivery. The adjustment was carried out with the aid of the mathematical model with s i (i = 1,2) referring to sex, e j (j = 1, 2, 3, 4) to season, and Pk (k = 1, 2, 3, 4, 5) to parturition. With the adjusted weights y ijkr obtained by the formula an analysis of variance was carried out, following the incomplete randomised model, with sires as blocks and cows as treatments using the theory developed by PIMENTEL GOMES (1967, 1968, 1970), with the following results. With the variance components E, Dand S thus obtained the estimates hI; 1 and hI; 2 of the coefficients of heritability were calculated, by formulas having been obtained the following results: hI; 1 = 0.6325 ± 0.28, hI; 2 = 0.6292 ± 0.28. This study permitted also the evaluation of the bulls and cows of the herd.Neste trabalho estimou-se o coeficiente de herdabilidade do peso aos 18 meses de idade do gado Canchim, que e o bimestiço 5/8 Charolês-Zebu, bem como avaliaram-se os reprodutores pela estimação dos efeitos de touros e vacas, em função de sua descendencia. Os estudos se basearam em 252 pesos aos 18 meses de animais oriundos de 15 touros e 94 vacas. Foram feitos ajustes para sexo, estação do ano e numero de ordem da parição da vaca. O ajuste foi feito com auxílio do modelo matemático y ijkr = m + + si + e j + pk + e ijkr, onde s i (i = 1 , 2) = efeito do sexo, e j (j =1, 2, 3, 4) = efeito da estação do ano, Pk (k = 1,2,3,4,5) = efeito da parição. Com os dados ajustados y ijkr>; obtidos pela formula y ijkr = Yijkr - si - êj - pk, foi feita a análise da variância seguindo-se o modelo de blocos incompletos, conforme PIMENTEL GOMES (1967, 1968, 1970), onde touros eram considerados como blocos e vacas como tratamentos. Os resultados obtidos foram: Com as estimativas dos componentes de variancia E, D, S, foram calculados os coeficientes de herdabilidade pelas formulas resultados foram: Tambera se estimaram os efeitos de touros e vacas o que permitiu apontar os melhores reprodutores do rebanho

Thermal characteristics of the radioactive graphite-CuO-Na2CO3-K2CO3-NaCl-KCl system in argon atmosphere

The article considers thermal characteristics of the radioactive graphite-CuO-Na2CO3-K2CO3-NaCl-KCl system in argon atmosphere. Thermodynamic calculations were carried out in the Terra program. Four temperature ranges with changes of thermal characteristics of the radioactive graphite-CuO-Na2CO3-K2CO3-NaCl-KCl system in argon atmosphere have been determined. © Published under licence by IOP Publishing Ltd

The emergence of meaningful geometry

publishedVersio