Thermodynamic modeling of the Pb + Bi melt evaporation under various pressures and temperatures

The composition of the vapor phase and the partial pressures of vapor components have been defined at pressures from 102 to 107 Pa and in the temperature range from 500 to 3000 K. Diagrams of liquid-vapor phase equilibria for the Pb-Bi system have been constructed. A good agreement between experimental results and the carried out calculations on the Pb-Bi phase diagrams is observed. © 2012 Elsevier B.V. All rights reserved

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

Propagação da pereira através de estacas folhosas em ambiente de nebulização

Two investigations were realized with pear leaf cuttings putted to rooting under mist. In the first investigation, apical and sub-apical cuttings were taken from the cultivars Seleta, Triunfo, Tenra and Le Conte. In the second, auxin was applied in apical and sub-apical cuttings taken from the Seleta cultivar. The results indicated the following: 1) 30, 60, 61 and 68% were the rooting average for Tenra, Seleta, Triunfo and Le Conte cultivars, respectively; 2) Apical cuttings results in 61% of rooting (26, 70, 72 and 78% to Tenra, Triunfo, Seleta and Le Conte cultivars), otherwise to the sub-apical cuttings were observed 48% of success (34, 50, 50 and 68% to 'Tenra', 'Seleta', 'Triunfo', and 'Le Conte', respectively); 3) The investigation with the Seleta cultivar confirmed the best efficiency in rooting of apical cuttings; 4) Application of auxin did not affect the percentage of rooting in leaf cuttings.Foram realizadas duas observações, fazendo-se enraizamento, de estacas folhosas de pereiras sob condições de nebulização intermitente. Na primeira foram tomadas estacas apicais e subapicais das variedades Seleta, Triunfo, Tenra e Le Conte. Na segunda fêz-se a aplicação da auxina Rootone em estacas apicais e sub-apicais da variedade Seleta. Verificou-se que: 1) As médias de enraizamento foram de 30, 60, 61 e 68% para as variedades Tenra, Seleta, Triunfo e Le Conte; 2) As estacas apicais resultaram em 61% de enraizamento (26, 70, 72 e 78% para as variedades Tenra, Triunfo, Seleta e Le Conte), contra 48% para as estacas sub-apicais (34, 50, 50 e 68% para as variedades Tenra, Seleta, Triunfo e Le Conte); 3) Observação realizada somente com a variedade Seleta, comprovou a maior eficiência no enraizamento para estacas apicais (75%) em relação as sub-apicais (40%); 4) A auxina não alterou as porcentagens de enraizamento das estacas folhosas de pera'Seleta'

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

Prediction of physical-chemical and fire hazard characteristics by carbon chain rules. 2. Carboxylic acids

Investigation of the dependence of physico-chemical and fire hazard properties from the chemical structure of carboxylic acids is carried out. Forecasting of the boiling temperature, the flash point, the temperature and the concentration flammability limits, the heats of combustion and vaporization is performed by the carbon chain rules (CCR). The following empirical equations for the calculation of physico-chemical and fire hazard indices from the conventional carbon chain and from the number of carbon atoms are proposed for the convenience of practical application of the CCR. A comparative analysis of the proposed methods for the flash point calculating and the already known methods of GOST 12.1.044-89, Mendeleev and ACD/Lab 2014 is carried out. It is shown, basically, that the new methods give more accurate calculation results than the comparison design procedures. © Siberian Federal University. All rights reserve

Classification of fermented cocoa beans (cut test) using computer vision

Fermentation of cocoa beans is a critical step for chocolate manufacturing, since fermentation influences the development of flavour, affecting components such as free amino acids, peptides and sugars. The degree of fermentation is determined by visual inspection of changes in the internal colour and texture of beans, through the cut-test. Although considered standard for evaluation of fermentation in cocoa beans, this method is time consuming and relies on specialized personnel. Therefore, this study aims to classify fermented cocoa beans using computer vision as a fast and accurate method. Imaging and image analysis provides hand-crafted features computed from the beans, that were used as predictors in random decision forests to classify the samples. A total of 1800 beans were classified into four grades of fermentation. Concerning all image features, 0.93 of accuracy was obtained for validation of unbalanced dataset, with precision of 0.85, recall of 0.81. Although the unbalanced dataset represents actual variation of fermentation, the method was tested for a balanced dataset, to investigate the influence of a smaller number of samples per class, obtaining 0.92, 0.92 and 0.90 for accuracy, precision and recall, respectively. The technique can evolve into an industrial application with a proper integration framework, substituting the traditional method to classify fermented cocoa beans

Cathodoluminescence of Recent biogenic carbonates: environmental and ontogenetic fingerprint

Cathodoluminescence (CL) examination of Recent biogenic carbonates shows that they are often luminescent regardless of their mineralogical composition (calcite v. aragonite), habitat (marine v. fresh water), way of life (sessile v. vagile) or environment (hyper- v. hyposaline water). Thus, the presence of luminescence in biogenic particles is not a reliable indicator of diagenetic alteration as some authors have suggested. In addition, CL can reveal variations in the mineralogy of shell material (e.g. regenerated calcitic v. primary aragonitic) and can highlight growth-related structures. Manganese (Mn2+) is the most likely activator of this luminescence, and its content in the shells of benthic organisms seems to be linked to growth rate, ontogeny, open sea conditions, bathymetry and salinity. In neritic environments the Mn2+ content and the CL of molluscs and foraminifera appear to increase with decreasing salinity. This study indicates that CL may be an important tool for the determination of environmental and ontogenetic parameters in biogenic carbonates in addition to its current use indiagenetic studie

Study of several varieties of tree crowns on different rootstocks of mango (Mangifera indica L.)

O objetivo deste trabalho foi verificar a interferência copa x porta-enxerto no desenvolvimento da mangueira. As alturas e os diâmetros das copas foram tomadas uma vez em 1981, quando as 210 plantas atingiram 15 anos de idade. As variedades de copas estudadas foram as seguintes: Extrema, Oliveira Neto, Carlota, Imperial, Pahiri e Bourbon. Os porta-enxertos utilizados foram Espada, Extrema, Olivara Neto, Carlota, Coco, Pahiri e Bourbon. Os dados foram analisados e a comparação das médias foi feita através do teste de Tukey em nível de 5% de probabilidade. O estudo mostrou que as variedades de copa, Olivara Neto, Extrema e Bourbon atingiram uma altura e um diâmetro maior que as demais variedades.The aim of this paper was to investigate the influence of the combination tree crown + rootstock on mango tree performance. The trees were selected according to height and crown diameter, measured once in 1981, using 210 trees, 15 years old at the beginning of the experiment. The Extrema, Espada, Oliveira Neto, Carlota, Bourbon, Coco and Pahiri varieties were used as rootstock and Extrema, Pahiri, Imperial, Oliveira Neto, Cariota e Bourbon were utilized as scions for tree crown development. Data were analysed by classical statistics, comparing means through the Tukey test, at a probability level of 5%. The crowns Oliveira Neto, Extrema e Bourbon showed the highest heights and diametres