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Copyright of Ingeniería del Agua is the property of Universidad Politecnica de Valencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Urban pests such as cockroaches prefer urban environments within and around the home to establish their colonies. These insects may potentially be more attracted to unconventional construction materials, which would mean a deterioration not only of the materials but also of urban environments. The objective of this study was to assess the degree of attraction of the "cockroach" Blattella germanica (L.) towards three non-conventional construction materials (Polyethylene Terephthalate - PET-, African Palm Kernel Ash - PKSA- and Polyethylene-Aluminum-Polyethylene pipe - PealPe) in tropical climates. An experimental study was carried out evaluating the attraction to B. germanica using an olfactometer. There was no preference of adult males and females of B. germanica towards unconventional concrete (p> 0,005). The selection time distribution was the same for the three concretes analyzed. There was no attraction of B. germanica towards non-conventional concretes made with PET, PeAlPe and PKSA; but a slight trend of choice towards concrete made with PKSA is evident. The use of non -conventional concrete can be an alternative for construction, both for complying with construction regulations and for not resulting more attractive to cockroaches than conventional materials such as concrete. [ABSTRACT FROM AUTHOR]

Copyright of Avances en Ciencias e Ingenierías (ACI) is the property of USFQ Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents a bibliometric review of the pyrolysis process of two types of polymers: polyethylene terephthalate (PET) and polystyrene (PS), to identify the necessary conditions to optimize the pyrolysis process, guaranteeing the majority production of the gaseous product with the aim of carrying out a second process, the growth of carbon nanostructures. Gaseous precursors such as methane, acetylene, and ethylene are essential hydrocarbons for the growth of said nanostructures, of which a variety of single-walled, double-walled, and multi-walled carbon nanotubes (SWCNTs, DWCNTs, and MWCNTs) stand out according to the literature and carbon nanofibers (CNFs). In this work, an analysis of the most relevant conditions is carried out to optimize the polymer pyrolysis process, that is, to reduce the temperature and reaction times to improve the composition of the products obtained from the pyrolytic process. Finally, the most relevant reports of the pyrolysis of the polymers exposed in the literature are disclosed. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Iteckne is the property of Universidad Santo Tomas, Division de Ingenierias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Iteckne is the property of Universidad Santo Tomas, Division de Ingenierias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The water flavored with fructooligosaccharides (FOS) constitutes a product developed at the Research Institute for the Food Industry and it is required to know its conservation, so the objective of this work was to evaluate the conservation of the waters flavored with FOS from pineapple-turmeric and orange-turmeric for a period of six months, packed in polyethylene terephthalate jars at room temperature. The FOS in the orange-turmeric flavored water did not undergo hydrolysis during storage; while in the pineapple-turmeric flavored water it maintained 75% of the initial concentration. The orange-turmeric flavored water presented 70 mg/L of chlorides, pH of 4.6 and a total hardness of 236 mg/L expressed as CaCO3, in addition to 100 mg/L of total solids; while that of pineapple-turmeric, had 71 mg/L of chlorides, pH of 4.1; total hardness was 232 mg/L expressed as CaCO3, and 100 mg/L of total solids. The products were not affected microbiologically during the study time and obtained a good global quality criterion. [ABSTRACT FROM AUTHOR]

Copyright of Ecosistemas y Recursos Agropecuarios is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencia y Tecnología is the property of Revista de Ciencia y Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The presence of microplastics (MPs, particles smaller than 5 mm) and the increase in temperature in the oceans, have been generating disturbances in marine life, which can be related to alterations in the metabolism of filter-feeders, such as Mythilids. Objective: The effect of different temperatures and concentrations of MPs on the filtration rate (TF) of Semimytilus algosus is evaluated. Methods: A sample of organisms (N = 72) was exposed to four temperatures (17, 20, 23 and 26 °C), and a control without microplastics (MPs0) and two concentrations of MPs (< 125 μm) of 0.125 mg/l (MPs1) and 0.250 mg/l (MPs2), all in combination with Isochrysis galbana microalgae (1x106 cells/ml/day) for 21 days. Results: As the concentration of MPs increased, the TF of S. algosus decreased. Regarding temperature, during day 7 a higher TF was observed at 23 °C in all treatments, and during days 14 and 21 the lowest TF values were obtained at 23 and 26 °C. The joint action of the increase in temperature and MPs, negatively affected the TF of S. algosus, where both factors caused the decrease in TF for all evaluation times. No mortality was recorded at 17 °C for any treatment, and in the case of mytylids exposed to MPs1 at 20 °C and 26 °C, the highest mortality (67 %) occurred. Conclusions: The study demonstrates the adverse effect of the increase in temperature and MPs on the TF of S. algosus. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ciencia Administrativa is the property of Universidad Veracruzana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The primary objective of this research study is to reuse waste concrete discarded from academic teachings and to recycle PET (Polyethylene Terephthalate) plastics to make garden planters. An innovative design of concrete curbs is proposed with weights ranging between 15 and 25 kg. Concrete mixtures with different PET additions (0, 0.5, and 1.0%) are characterized experimentally and an analysis of sustainability solution aspects is performed. The results show that discarded concrete can achieve the minimum resistance to compression of 15 MPa for all the mixtures studied. Using this solution, it is estimated that six tons of concrete are reused per year, up to 40 PET bottles per concrete curb are recycled, 40.66 kg of CO2 emissions are avoided annually, and 1,345.40 kWh of energy consumption are saved. It is concluded that the concrete curb mixture developed from recycled materials to make garden planters is an excellent alternative to reduce waste concrete and to recycle PET plastics. [ABSTRACT FROM AUTHOR]

In this study the behavior of dry bee pollen during storage was evaluated, two storage temperatures 5 and 29 °C and two packaging materials were considered: amber polyethylene terephthalate (PET) bottles and double zipper polyethylene (PE) bags. The dry pollen was carried out physical-chemical measurements (humidity, acidity, pH and proteins) and microbiological (microorganisms at 30 °C, filamentous fungi and yeasts) every seven days to 70 days of storage. It was observed that the pH, acidity and protein values did not vary significantly (p > 0,05) during the period for any of the storage alternatives studied, while the humidity for the samples stored in the bags at room temperature showed an appreciable increase with respect to the initial value, from 5,17 to 7,33 %. In the case of microbiological indicators, no increase was observed during the period. [ABSTRACT FROM AUTHOR]

The aim this work was to describe the effect of the application of antioxidants and packing in the conservation of oyster mushrooms (Pleurotus ostreatus), an edible mushroom with high protein value. This type of mushrooms is highly perishable and browning rapidly during postharvest. The whole oyster mushrooms were treated with ascorbic acid (1% w/v) and citric acid (1% w/v), packed in low-density polyethylene bags (PE), expanded polystyrene trays (PES) with PVC and polyethylene terephthalate (PET) containers. The mushrooms were stored at 5±1 °C and 85 ± 5% relative humidity, during 17 days. The physical-chemical, color and sensory properties were evaluated. The applied organic acids showed an antioxidant activity and in synergy with the packing, they maintain the evaluated properties of the oyster mushrooms. The oyster mushroom treated with antioxidants, conditioned in PET packing and stored at 5±1 °C and 85 ± 5% relative humidity, maintains its stability for 15 days. [ABSTRACT FROM AUTHOR]

The continuous demand for plastics has caused large accumulations of waste in landfills, contributing to environmental and public health problems. In Colombia, approximately 9,5 million tons of solid waste is generated annually, and 14% corresponds to plastic materials. Pyrolysis is a technique by which it is possible to remedy part of the problem, because energy and products are recovered in the form of liquid and gaseous fuel. This article presents the implementation and comparison of two models in Aspen Plus for the simulation of the pyrolysis process for the production of liquid fuels from different plastic waste. The models are based on the minimization of Gibbs free energy and reaction kinetic mechanisms. The simulation performed calculates the yields (% of weight) and the properties of each product flow according to the operating conditions. In comparison with data from the literature and experimental information collected in this research, the thermodynamic model showed deviations greater than 20%. The kinetic model presented good estimates obtaining errors = 8%. According to the results obtained, the production of liquid fuel from plastic wastes is favored according to the raw material as follows: polystyrene > high density polyethylene ? low density polyethylene > polyethylene terephthalate. [ABSTRACT FROM AUTHOR]

This research paper, financed by the Eafit University, presents the experimental results in which resistance to compression and manageability of a concrete mix made with a partial replacement for the fine aggregate with polyethylene terephthalate (PET) was assessed. The replacement was made by volume, thus the space occupied by the extracted sand particles will be occupied by the PET. Different concrete mixes with sand replacement were made going from 0 % (reference), 5 %, 10 %, 15 % and 20 %. The results indicate that increasing the replaced sand percentage decreases the resistance to compression, nonetheless, the manageability is not affected by keeping the granulometric curvature of the aggregates. The replacement percentage of 15 % was determined as the more adequate given its appropriate manageability, a great amount of sand is replaced and an acceptable resistance to compression is obtained. [ABSTRACT FROM AUTHOR]

Introduction: Fast population growth has generated an increase in the consumption and therefore it has influenced the rise of the solid waste generation, which causes adverse effects on the environment if treated inadequated. Polyethylene terephthalate (PET) is a kind of solid waste generated that is 100% recyclable, however it is ending in landfills reducing the lifespan of them and consuming resources like petroleum in order to generate new products. Objective: Evaluating the effect on the environment of PET recycling by means of a system dinamics model. Material and method: The variables considered were water and energy consumption, CO2 emissions and landfill lifespan varying the PET recycling rate. RESULTS: the increase of the recycling rate cause a decrease in water and energy consumption as well as de CO2 emissions and produce a rise in the landfill lifespan. Conclusions: It is still important to follow the acomplishment of the solid waste management policies so as to enhace the decision making process related to generate a positive impact on the environment. [ABSTRACT FROM AUTHOR]

In this paper we present the results of implementing an algorithm based on Support Vector Machine (SVM) on the National Instruments platform Compaq Rio, abbreviated cRio for the detection of Polyethylene terephthalate (PET) containers leakage. To accomplish this, the acquisition and processing the differential pressure signal is performed and then using a decision model to determine whether the package leaks or not. There are many tools for digital signal processing, however in the SVM classification applications have proven to be a very good alternative. The SVM requires a training process, performed based on signals which are known class to which they belong. After this training, a classification is performed in a new bottle. The final algorithm is implemented on the cRio National Instruments system for online application. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the last years solid waste disposal has increasing significantly, causing health and environmental problems. In order to study an alternative to mitigate these problems, the re-use of polyethylene- terephthalate bottles as a replacement of conventional lightweight materials used on the leveling or filling of soils is investigated. For this purpose, a mechanical characterization of the PET most popular bottles on the market was carried out. Laboratory test results indicate that PET bottles exhibit compression resistances, which suggest that this material can be used on the construction of lightweight structures. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencia y Tecnología is the property of Revista de Ciencia y Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of E-Gnosis is the property of Universidad de Guadalajara, Coordinacion General Academica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se presenta un estudio experimental del efecto de las condiciones de reprocesamiento sobre las propiedades de desechos plásticos PET (polietilentereftalato). Se consideran las variables del tiempo de retención del polímero (en la cámara de procesamiento) y la temperatura de procesamiento, se obtiene la ecuación de regresión del sistema y se calculan las condiciones optimas para minimizar la degradación del polímero.