A METHODOLOGY FOR EVALUATING FIELD PERFORMANCE AND EMISSIONS OF A GAS MICROTURBINE BASED COGENERATION SYSTEM

Due to its high economic impact, when a new technology is handed over from manufacturer to customer, the contractually fixed guarantees and specifications have to be proven. Besides guarantees concerning environmental tasks, such as flue gas emissions, the availability and performance data of the new technology are the key issue. Field performance usually lacks very accurate measuring equipments and stable measurement conditions, as in many manufacturer testing laboratories. In this work a methodology was developed to evaluate performance and emissions under field conditions, together with a critical analysis of the resulting uncertainty of the main parameters, which are representative of the system performance, which was also detailed. In order to overcome field measurement difficulties, a methodology was used to measure combustion air flow rate from emission and gas flow rate measurements. The evaluation procedure was demonstrated by testing a microturbine based cogeneration system, which comprises a microturbine, a heat recovery system, and a steel storage hot water tank, providing electrical energy to Pontifical Catholic University of Rio de Janeiro grid and thermal energy for heating domestic water in cogeneration to its gymnasium showers. Data were acquired at carefully chosen stable test periods in which the gas microturbine was setup to produce electrical energy at nominal power outputs of 100, 75, 50 and 25% of maximum load. In addition, this paper presents an economical analysis for the system, which operates during peak hours (17:30 to 20:30) from Monday to Friday

A METHODOLOGY FOR EVALUATING FIELD PERFORMANCE AND EMISSIONS OF A GAS MICROTURBINE BASED COGENERATION SYSTEM

Due to its high economic impact, when a new technology is handed over from manufacturer to customer, the contractually fixed guarantees and specifications have to be proven. Besides guarantees concerning environmental tasks, such as flue gas emissions, the availability and performance data of the new technology are the key issue. Field performance usually lacks very accurate measuring equipments and stable measurement conditions, as in many manufacturer testing laboratories. In this work a methodology was developed to evaluate performance and emissions under field conditions, together with a critical analysis of the resulting uncertainty of the main parameters, which are representative of the system performance, which was also detailed. In order to overcome field measurement difficulties, a methodology was used to measure combustion air flow rate from emission and gas flow rate measurements. The evaluation procedure was demonstrated by testing a microturbine based cogeneration system, which comprises a microturbine, a heat recovery system, and a steel storage hot water tank, providing electrical energy to Pontifical Catholic University of Rio de Janeiro grid and thermal energy for heating domestic water in cogeneration to its gymnasium showers. Data were acquired at carefully chosen stable test periods in which the gas microturbine was setup to produce electrical energy at nominal power outputs of 100, 75, 50 and 25% of maximum load. In addition, this paper presents an economical analysis for the system, which operates during peak hours (17:30 to 20:30) from Monday to Friday

Effect of fibrin-rich plasma and collagen sponge on healing of the palatal mucosa

The purpose was to evaluate the variation in thickness and early healing of the donor area of the palate with the placement of a collagen sponge and the use of fibrin-rich plasma (L-PRF).Thirty patients who required mucogingival surgery treatment were selected and distributed into 2 groups. After obtaining the free palate graft, L-PRF was placed in Group A, and a collagen sponge was placed in Group B. The healing process of the palate was evaluated at 24 hours and 7, 14, 21 and 28 days postsurgery. The thickness of the donor area (palate) was evaluated using an acrylic splint. These measurements were made before and 4 months after surgery.In the collagen sponge group, less gain of the palatal mucosa was observed, with a mean difference of 0.1 ± 0.8 mm (CI: −0.341–0.518) (p=0.691), whereas in the fibrin-rich plasma group, a mean difference of 0.0 ± 0.5 mm (CI: −0.229–0.229) (p=0.934) was found; however, when comparing the gain of the palatal mucosa in both groups, no significant difference was observed (p=0.932). The healing index at 24 hours indicated the presence of clots, on Day 28 vascularisation and total epithelialisation (100.0%), and finally, the collagen sponge group on Day 14 presented 93.3% partial vascularisation of connective tissue and 33.3% L-PRF (p=0.001).There was no statistically significant difference in the thickness of the palatal mucosa after the use of L-PRF and the collagen sponge

Some color in the desert: description of a new species of Liolaemus (Iguania: Liolaemidae) from southern Peru, and its conservation status.

The desert of southern Peru and northern Chile is an area with a high degree of endemismin squamate reptiles. In this work, an endemic new species is described in the genus Liolaemus with a restricted geographical distribution on the western slopes of the La Caldera batholith in the Department of Arequipa, southern Peru, that inhabits the Desert province of southern Peru, between 1,800 and 2,756 m asl. The new species is characterized by a unique combination of morphological and molecular characters that distinguish it from all other Liolaemus species, and it is included in the L. reichei clade within the L. montanus group. Evidence presented shows that the category of threat corresponds to Endangered under the IUCN Red List criteriaFil: Huamani Valderrama, Ling. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; PerúFil: Quiroz, Aarón J.. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; PerúFil: Gutierrez, Roberto C.. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; PerúFil: Aguilar Kiriguin, Alvaro. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; PerúFil: Huanca Mamani, Wilson. Universidad de Tarapacá; ChileFil: Valladares Faúndez, Pablo. Universidad de Tarapaca.; ChileFil: Cerdeña, José. Universidad Nacional de San Agustín. Facultad de Ciencias Biológicas. Departamento Académico de Biología. Museo de Historia Natural; PerúFil: Chaparro, Juan C,. Museo de Biodiversidad del Perú; PerúFil: Abdala, Cristian Simón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

Efecto de Temperatura y Velocidad de Agitación en el Deshidratado Osmótico de Jengibre (Zingiber Officinale)

The objective of this research was to evaluate the effect of temperature and agitation speed on weight loss (WeL%), water loss (WaL%) and solids gain (SG%) in the osmotic dehydration of ginger cubes. (Zingiber officinale). The applied parameters were: osmotic solution temperature 26, 36, and 46°C, stirring speed of 30, 50 and 80 rpm, sample/osmotic solution ratio of 1:16 (p/p), sucrose concentration at 60% and experiment time 0, 15, 30, 45, 60, 75, 90, 105 and 120 min. The results showed that the temperature was the parameter that most influenced the WaL%, WeL%, and SG%, compared to the agitation speed it had a lower influence on the WaL%, WeL%, and SG%, this indicates that the high temperatures cause changes in the permeability of the cell membrane of the food, which generates greater transfer. The 26°C and 30 rpm treatment showed a higher diffusivity (De) with 5,20 x 10-4. The 46°C and 30 rpm treatment reported higher moisture losses with 35%, the 26°C and 30 rpm treatment presented an increased pH variation from 6.62 to 5.27, the 36°C and 50 rpm treatment showed a constant acidity of 0.05% and the treatment of 46°C and 80 rpm increase variation in soluble solids concentration to 35.16 °Brix. It was shown that temperature is the parameter that most influenced WaL%, WeL%, and SG%.El objetivo de esta investigación fue evaluar el efecto de la temperatura y la velocidad de agitación sobre la pérdida de peso (PP%), la pérdida de agua (PA%) y la ganancia de sólidos (GS%) en el deshidratado osmótico de cubos de jengibre (Zingiber officinale). Los parámetros aplicados fueron: temperatura de la solución osmótica 26, 36 y 46°C, velocidad de agitación de 30, 50 y 80 rpm, relación muestra / solución osmótica de 1:16 (p/p), concentración de sacarosa al 60% y tiempo de experimento 0, 15, 30, 45, 60, 75, 90, 105 y 120 min. Los resultados mostraron que la temperatura fue el parámetro que más influyó sobre la PA%, PP% y GS%; en comparación, la velocidad de agitación tuvo una menor influencia sobre la PA%, PP% y GS%; esto indica que las altas temperaturas provocan cambios en la permeabilidad de la membrana celular del alimento, lo que genera mayor transferencia. El tratamiento a 26°C y 30 rpm mostró una mayor difusividad (De) con 5.20 x 10-4. El tratamiento a 46 °C y 30 rpm reportó mayores pérdidas de humedad con un 35%, el tratamiento a 26°C y 30 rpm presentó mayor variación de pH de 6.62 a 5.27, el tratamiento a 36 °C y 50 rpm mostró una acidez constante de 0.05% y el tratamiento a 46°C y 80 rpm presentó una mayor ganancia de sólidos soluble con 35.16 °Brix. Se demostró que la temperatura es el parámetro que más influeyó sobre PA%, PP% y GS%

Cataclysmic Variables from Sloan Digital Sky Survey V -- the search for period bouncers continues

SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of cataclysmic variables (CVs) and CV candidates obtained during the final plug plate observations of SDSS. We identify eight new CVs, spectroscopically confirm 53 and refute eleven published CV candidates, and we report 21 new or improved orbital periods. Combined with previously published data, the orbital period distribution of the SDSS-V CVs does not clearly exhibit a period gap. This is consistent with previous findings that spectroscopically identified CVs have a larger proportion of short-period systems compared to samples identified from photometric variability. Remarkably, despite a systematic search, we find very few period bouncers. We estimate the space density of period bouncers to be $\simeq0.2\times10^{-6}\,\mathrm{pc}^{-3}$, i.e. they represent only a few per cent of the total CV population. This suggests that during their final phase of evolution, CVs either destroy the donor, e.g. via a merger, or that they become detached and cease mass transfer.Comment: Submitted to MNRA

Impactos do coronavírus 2019 (COVID-19) no meio ambiente

Introduction: COVID-19 brought effects at a general level, one of them is in the environment for which its study is necessary to propose solutions to this pandemic. The objective is to determine the effects that COVID-19 has brought to the environment, through a descriptive study and documentary review. Obtaining consequences in the air, soil and water spheres that generate visible impacts on society, the economy and mainly on the environment. In conclusion, there are positive environmental effects, such as the improvement of air quality; and negative, such as the high contamination by medical and domestic waste, the latter being the most alarming. To this end, reflections and proposals for measures to counteract them are proposed.Introducción: La COVID-19 trajo efectos a nivel general uno de ellos es en el ambiente por el cual su estudio se hace necesario para plantear propuestas de solución ante esta pandemia. El objetico es determinar los efectos que ha traído la COVID-19 en el ambiente, por medio del estudio descriptivo y la revisión documental. Obteniéndose consecuencias en las esferas aire, suelo y agua que generan impactos visibles en la sociedad, la economía y principalmente en el ambiente. En conclusión, existen efectos ambientales positivos, como la mejora de la calidad del aire; y negativos, como la elevada contaminación por residuos médicos y domésticos, siendo este último el más alarmante. Para ello se plantea reflexiones y propuestas de medidas para contrarrestarlos.Introdução: O COVID-19 trouxe efeitos em nível geral, um deles é no meio ambiente para o qual seu estudo é necessário para propor soluções para esta pandemia. O objetivo é determinar os efeitos que o COVID-19 trouxe ao meio ambiente, por meio de um estudo descritivo e revisão documental. Obtendo consequências nas esferas do ar, solo e água que geram impactos visíveis na sociedade, na economia e principalmente no meio ambiente. Em conclusão, há efeitos ambientais positivos, como a melhoria da qualidade do ar; e negativos, como a alta contaminação por resíduos hospitalares e domésticos, sendo este último o mais alarmante. Para tanto, são propostas reflexões e propostas de medidas para combatê-los