The current paper deals with the way in which the liquid-vapor equilibrium can be predicted, using the program Microsoft-Excel to obtain the bubble temperatures of twenty different non-ideal mixtures, the location of ...The current paper deals with the way in which the liquid-vapor equilibrium can be predicted, using the program Microsoft-Excel to obtain the bubble temperatures of twenty different non-ideal mixtures, the location of the azeotrope and the relation of the minimal reflux. The Wilson model was used for the activity coefficient and the cubic equation of state was used for the fugacity coefficient, utilizing the Pitzer correlation for the second virial coefficient.展开更多
The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of ...The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI (the card's printed circuit) which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, Fe, Ag, Au and Pt.展开更多
The importance of evaluating the leaf area in red tomato plants aims to determine the growth and development of crops established two production cycles, spring-summer and autumn-winter to compare the influence of temp...The importance of evaluating the leaf area in red tomato plants aims to determine the growth and development of crops established two production cycles, spring-summer and autumn-winter to compare the influence of temperature on the growth of leaf area. Repeated, weekly samples were taken by identifying the week and determining the growth and leaf area development using Markov chains, using an array of transition to describe and represent in a flowchart the finite number of physiological States. With the analysis in the steady state process and applying the equations of odds, we get that leaf area growth is established from the seventh week shown in the first cycle (C1) with the chance of 0.266, 0.264 and 0.263, in the last two weeks. It was observed an increase of 6% in the cycle autumn-winter cycle compared spring-summer.展开更多
文摘The current paper deals with the way in which the liquid-vapor equilibrium can be predicted, using the program Microsoft-Excel to obtain the bubble temperatures of twenty different non-ideal mixtures, the location of the azeotrope and the relation of the minimal reflux. The Wilson model was used for the activity coefficient and the cubic equation of state was used for the fugacity coefficient, utilizing the Pitzer correlation for the second virial coefficient.
文摘The life of electronic equipment is becoming increasingly shorter and its replacement always generates a quantity of waste increase, giving rise to a problem of environmental character and still needed new options of solid waste management that will contribute to global sustainable development. Parts of these waste are TCI (the card's printed circuit) which containing dangerous elements and turns them into a polluting material from the soil, water and air, being harmful to human health if there is to proper and responsible way, so the recycling of TCI to obtain precious metals is an example of industrial materials that can be recycled. Despite this, large quantities of these are not recycled and some others are not considered. The objective of this work is to present a systematic and ecological methodology for the recovery of valuable materials contained in parts of used in computers, circuit boards using a leaching process. The method determines a set of variables to evaluate the kinetics of the reaction and the leaching of metals that form the substrate of metal and to establish the parameters that affect the rate of leaching of metals through a sensitivity analysis, to identify design alternatives. It determines the quantity and percentages that constitutes the motherboard, processor, video cards, accelerator graphics, network and memory cards RAM, among others and its content of metals such as Cu, Fe, Ag, Au and Pt.
文摘The importance of evaluating the leaf area in red tomato plants aims to determine the growth and development of crops established two production cycles, spring-summer and autumn-winter to compare the influence of temperature on the growth of leaf area. Repeated, weekly samples were taken by identifying the week and determining the growth and leaf area development using Markov chains, using an array of transition to describe and represent in a flowchart the finite number of physiological States. With the analysis in the steady state process and applying the equations of odds, we get that leaf area growth is established from the seventh week shown in the first cycle (C1) with the chance of 0.266, 0.264 and 0.263, in the last two weeks. It was observed an increase of 6% in the cycle autumn-winter cycle compared spring-summer.