Search

The objectives of the paper were to evaluate particle mass concentrations of PM1 (size

Studies published in the period from 2014 to 2018 that are aimed at creating nondispersive and photoacoustic IR gas analyzers with LED radiation sources based on А3В5 heterostructures and operating in a range of wavelengths from 3 to 5 μm are reviewed. Potential of gas analysis equipment based on the aforementioned LEDs for detecting CO, CO2, methane, and other gases is analyzed.

El desarrollo industrial en el Ecuador se ha expandido sin los suficientes controles ambientales degradando la calidad del aire y afectando a la salud de la población. La presente investigación tuvo como objetivo determinar los contaminantes atmosféricos generados por las Empresas Don Jorge y Productos Lácteos San Enrique del Cantón Latacunga, Provincia de Cotopaxi. Los gases monitoreados fueron O2, CO2, CO, NOx y SO2 con el analizador de gases de combustión TESTO 350. Los datos recopilados en las Empresas: Embutidos Don Jorge y Productos Lácteos San Enrique fueron tratados en base a la Norma Técnica USEPA y comparados con los límites máximos permisibles establecidos en la Normativa Ambiental Vigente Ecuatoriana (TULSMA). Los resultados de dichas empresas se las dividieron en dos grupos: Fuentes en operación hasta el 2003 y despues del 2003, como indica la norma ambiental. La primera empresa obtuvo el 30% que cumple con los niveles permisibles de gases contaminantes, mientras que la segunda empresa cumple con el 42%. Con el estudio se concluye que las empresas en estudio estan causando impactos negativos en la calidad de aire de la ciudad y la Provincia.

Physiological traits are essential to understand the performance of plants in response to environmental conditions. We describe physiological responses related to gas exchanges in leaves of eight woody species in the savanna ecosystem of the Amazonian domain during the dry season. A portable gas analyzer was used to measure photosynthesis (A), transpiration (E), stomatal conductance (gs) and leaf temperature (TL). We applied A and E to calculate water use efficiency. Time of day showed significant influence on the E, TL and WUE values. The association between E and gs occurred in all plants measured, and this result indicated a trend of physiology responses convergence. Our results contribute to clarify remarkable physiological aspects of the savanna vegetation, which suffers from lack of knowledge while facing an accelerated degradation process.

Although only 2–4% of absorbed light is emitted as chlorophyll (Chl) a fluorescence, its measurement provides valuable information on photosynthesis of the plant, particularly of Photosystem II (PSII) and Photosystem I (PSI). In this paper, we have examined photosynthetic parameters of Suaeda fruticosa L. (family: Amaranthaceae), surviving under extreme xerohalophytic conditions, as influenced by diurnal rhythm or continuous dark condition. We report here CO2 gas exchange and the kinetics of Chl a fluorescence of S. fruticosa, made every 3 hours (hrs) for 3 days, using a portable infra-red gas analyzer and a Handy PEA fluorimeter. Our measurements on CO2 gas exchange show the maximum rate of photosynthesis to be at 08:00 hrs under diurnal condition and at 05:00 hrs under continuous dark. From the OJIP phase of Chl a fluorescence transient, we have inferred that the maximum quantum yield of PSII photochemistry must have increased during the night under diurnal rhythm, and between 11:00 and 17:00 hrs under constant dark. Overall, our study has revealed novel insights into how photosynthetic reactions are affected by the photoperiodic cycles in S. fruticosa under high salinity. This study has further revealed a unique strategy operating in this xero-halophyte where the repair mechanism for damaged PSII operates during the dark, which, we suggest, contributes to its ecological adaptation and ability to survive and reproduce under extreme saline, high light, and drought conditions. We expect these investigations to help in identifying key genes and pathways for raising crops for saline and dry areas.

OBJECTIVE This study aimed to compare the physiological responses induced by the modified shuttle walk test (MSWT), the 6-minute walk test (6MWT), and the pediatric Glittre activities of daily living test for children (TGlittre-P) in healthy children. METHOD This was an analytical observational cross-sectional study. All subjects underwent an anthropometric evaluation, pulmonary function test, TGlittre-P, 6MWT, and MSWT using a portable gas analyzer. Each test was conducted on the same day, and a maximum period of 15 days was considered for completion of the 3 days of data collection. RESULTS Overall, 24 subjects were included (mean age, 9.78 ± 1.27 years). The peak oxygen consumption (VO2peak ) during the MSWT (1409.94 ± 285.13 mL/kg/min) was significantly higher than that during the TGlittre-P (982.19 ± 205.95 mL/kg/min) and 6MWT (982.85 ± 257.09 mL/kg/min) (P

The conceptual provisions and strategical aspects of the monitoring of the chemical composition of the atmosphere at manned spacecrafts and space stations which can be used in the execution of long-term and interplanetary space flights are proposed and substantiated. The major risk factors of the change in the composition of the atmosphere in the case of interplanetary space flights are formulated. Current advances in the field of monitoring are critically evaluated, which allows the choice of directions for new domestic designs to be substantiated. A promising version of an analytical complex for the operational control of the quality of the air in manned spacecrafts and space stations is described that takes into account the major risk factors. To provide the partial overlapping of the nomenclature of the detectable substances in terms of the most important (critical) compounds, it is proposed to simultaneously use several methods of gas analysis based on different physical principles. It is concluded that the implementation of such a monitoring system will make it possible to analyze a wide range of substances on a full scale and will provide an operational analysis of the quality of the air in manned spacecrafts and space stations, not only in usual operations but also in contingency (emergency) events.

The eddy covariance technique (EC) is used at hundreds of field sites worldwide to measure trace gas exchange between the surface and the atmosphere. Data quality and correction methods for EC have been studied empirically and theoretically for many years. The recent development of new gas analyzers has led to an increase in technological options for users. Open-path (no inlet tube) and closed-path (long inlet tube) sensors have been used for a long time, whereas enclosed-path (short inlet tube) sensors are relatively new. We tested the comparability of fluxes calculated from five different gas analyzers including two open-path (LI-7500 A from LI-COR, IRGASON from Campbell), two enclosed-path (CPEC200 from Campbell, LI-7200 from LI-COR), and one closed-path (2311-f from Picarro) analyzers, which were all located on a single tower at an irrigated alfalfa field in Davis, CA. To effectively compare sensors with different tube characteristics we used three different spectral correction methods. We found that all sensors, regardless of type, can be used to measure fluxes if appropriate corrections are applied and quality control measures are taken. However, the comparability strongly depended on the gas (CO2 or H2O) and the correction method. Average differences were below 4% for CO2 fluxes using any spectral correction method, but for H2O average differences were between 4% and 13% for the different methods. The magnitude of corrections also varied strongly, especially for water vapor fluxes. This study does not identify the best sensor, but rather weighs the benefits and difficulties of each sensor and sensor type. Our findings show that enclosed and closed-path gas analyzers that measure water vapor with inlet tubes experience large high frequency attenuation and should be corrected with empirical correction methods. This information presented here about different the diverse sensors be considered by investigators when choosing a sensor for a site or when analyzing EC measurements from multiple sites.

A hydrogen supported turbulent pulverized coal combustion flame was investigated experimentally and numerically to analyze combustion characteristics and flame structure. The flame was experimentally investigated by direct measurement methods and non-intrusive optical diagnostic methods. Temperature of gaseous phase was observed by a sheathed thermo-couple, while gas composition was examined by a gas analyzer with a sampling probe. Particle dispersion characteristics and velocity were analyzed by Mie scattering and PIV techniques using an optical measurement system. A numerical analysis was simultaneously performed to investigate the flame in detail by means of LES. The simulation was validated by comparing gaseous temperature, velocity and composition results to the experiment. The issued pulverized coal particles were distributed in limited area even in downstream by forming linear shape of flame. The particles moved by forming a cloud in the flame in upstream, but the cloud was broken up in downstream when it passed the flame surface. The characteristics of particle movement and influence of combustion were discussed with the analyses of particle velocity and momentum transfer. The flame structure was discussed with the results of gaseous mole fraction, and NOx formation was numerically investigated in this study.

This study was aimed to determine the level of CO concentration due to traffic flows, know the traffic (vehicle) volume, traffic (vehicle) speed and wind speed, find out the relationship between traffic (vehicle) volume, traffic (vehicle) speed, wind speed and CO concentration using a regression model as well as examine the parameters influencing air pollution due to traffic flows. The primary data used in this study were the sample data of CO tested directly in the field and the sampling was done using Ecoline 6000 Gas Analyzer tool. The research sites covered 1) the segment of Sam Ratulangi Street in Manado representing the street locations with many multi-rise buildings and high building density, 2) the segment of Ahmad Yani Street in Manado representing the street locations with many trees, and 3) the segment of Pierre Tendean Street in Manado representing the street locations with open areas (beachsides). In this modeling, the independent variables were the total traffic volume, the average traffic speed as well as the wind speed and direction. The dependent variable was Carbon Monoxide (CO) with increased concentrations. Using the three independent variables, there were total 7 (seven) variable combinations used. Then, the obtained model was validated using the surveyed data. The maximum vehicle volume was 4,281.60 pcu/hour (pcu = passenger car unit) and the maximum vehicle speed was 32 km/hour. Meanwhile, the maximum wind speed generated was 7.5 km/hour and the maximum level of air pollution (CO) was 12.86 ppm (ppm = part per million). In this study, it was obtained the best model for each of the three locations. The results showed that the air pollution (CO) level of street locations with low wind speed, such as Sam Ratulangi street which is a closed area with many multi-rise buildings and high building density, was much higher than that of street locations with many trees growing in the median of streets with a distance of 1 meter from the edge of street pavement and also higher than that of street locations with open areas (beachsides). This is because a higher wind speed can disseminate or divide the concentration level of air pollution (CO) to various places. Air pollution control covers three stages namely the prevention, countermeasure, and recovery of air quality.

The high population in Indonesia has an impact on increasing the mobility of the population in work and activities, which is followed by the increased transportation facilities needed by the community. One of the negative effects of the increasing number of vehicles is the danger of exhaust emissions. One way to minimize the danger of exhaust gases is to regulate the mixture of air and fuel on the gasoline engine. In Yamaha injection motors there is a CO setting technology, this technology will have an impact on fuel use. The standard CO on a Yamaha motorbike is 0 and can be added or reduced (±) until it reaches 30. Increasing CO one strip will cause the fuel sprayed by the injector to be reduced by 0.05 cc. Examination of exhaust gas emissions is carried out using the Qrotect 401 Engine Gas Analyzer which is capable of measuring CO2, O2, CO, HC and Lamda. Based on the test results show that the lowest exhaust emissions are produced by the vehicle at 2500 rpm and in CO-30 mode settings, namely CO gas emissions of 0.49%. So we can conclude that the lowest exhaust gas emissions are produced by the vehicle at rpm 2500 with CO-30 settings. In addition to co mode settings, variations in engine rpm also affect exhaust emissions. In different modes but with different rpm the results will also be different. In the CO 10 mode setting with rpm 1400 CO gas emission is produced at 2.102 while at 2500 rpm is produced 0.821. So at rpm 2500 produced exhaust emissions lower than rpm 1400. There is a significant effect between CO mode settings and engine rpm on motorcycle exhaust emissions.

To investigate the conversion of nitrogen bound in biomass fuel (abbreviated to fuel-N) during biomass pyrolysis, wheat straw (WS), rice straw (RS), spent coffee grounds (SCG) and palm kernel cake (PKC) were isothermally pyrolyzed in a horizontal tube reactor at the temperature range of 500–900 °C. The concentrations of light gaseous nitrogen containing species (gas-N) were measured online by a Fourier transform infrared (FTIR) spectroscopy gas analyzer, and the corresponding conversion rates were calculated. Results indicated that the conversion of fuel-N to gas-N as well as the evolution of N-functionalities in the portion of fuel-N that maintained in the char (char-N) were consistent regardless of the original N-functionalities in biomass samples. The conversion of fuel-N was found to be highly reliant on the temperature and fuel-N content. 17–47% of the fuel-N was finally retained in the char during pyrolysis. Therefore, the evolution of the N-functionalities from fuel-N to char-N was analyzed by X-ray photoelectron spectroscopy (XPS). Amide-N (N-A) was confirmed to be the dominant N-functionality in the raw biomass samples, and a small amount of pyrrolic-N (N-5), pyridinic-N (N-6) and quaternary-N (N-Q) were also identified. After pyrolysis, N-A was completely vanished in the char. However, only a very small fraction of N-A was decomposed into NH3 while most of it was preferentially converted to other gas-N (HCN, HNCO and NO) and N-5/N-6. For N-5/N-6, most of them preferred to retain in the char. As the temperature increased, a small amount of N-5/N-6 was converted to more stable N-Q and N-oxides (N-X) structures. Contrary to expected, N-A was also the main contributor to the formation of HCN, while the contribution from N-5/N-6 was less important. Finally, the conversion mechanism of fuel-N was concluded.

Prediction of clean hydrogen production via biomass gasification by supervised machine learning algorithms was studied. Lab-scale gasification studies were performed in a steel fixed bed updraft gasifier having a cyclone separator. Pure oxygen, and dried air with varying flow rates (0.05–0.3 L/min) were applied to produce syngas (H2, CH4, CO). Gas compositions were monitored via on-line gas analyzer. Various regression models were created by using different Machine Learning (ML) algorithms which are Linear Regression (LR), K Nearest Neighbors (KNN) Regression, Support Vector Machine Regression (SVMR) and Decision Tree Regression (DTR) algorithms to predict the value of H2 concentration based on the other parameters that are time, temperature, CO, CO2, CH4, O2 and heating value. The highest hydrogen value in syngas was found around 35% vol. after gasification experiments with higher heating value (HHV) of approximately 3400 kcal/m30.05 L/min and 0.015 L/min were the optimum flow rates for dried air and pure oxygen, respectively. In modeling section, it was observed that H2 concentrations were being reflected effectively by the concentrations estimated through the proposed model structures, and by having r2 values of 0.99 which were ascertained between actual and model results.

This study focused on the effect of steam on the transformation of sulfur during pyrolysis of demineralized coal in a horizontal tube furnace within the range of temperatures from 300 to 800 °C. The main sulfur-containing products in the resulting pyrolysis gases including H2S, SO2, and COS were quantitatively measured using ion chromatography combined with Fourier-transform infrared spectroscopy gas analyzer. The transformation of pyrite in char was assessed based on X-ray diffraction, while the organic sulfur was determined using both an infrared sulfur analyzer and X-ray photoelectron spectroscopy. The experimental results indicated that sulfur in the demineralized coal was primarily converted to H2S during pyrolysis under both argon and steam/argon atmospheres. During steam/argon pyrolysis, the steam promoted the formation of H2S while inhibiting the formation of SO2, thus increasing and decreasing the yields of these two compounds, respectively. In the argon atmosphere, the pyrite decomposed completely into pyrrhotite at 500 °C and was then converted to troilite at 600 °C. In the steam/argon atmosphere, different iron-containing compounds (Fe1−xS, Fe3O4, and FeO) were formed during the demineralized coal pyrolysis. The promotion of the pyrite transformation by steam was especially pronounced at temperatures above 500 °C. The organic sulfur removal was found to increase likely because the addition of steam above 500 °C promoted the decomposition of thiophenic sulfur.

We assessed the impacts of native and non-native tree species and seasonal variation on in situ soil respiration rates for four seasons. A portable infrared carbon dioxide (CO2) gas analyzer (Q-Box SR1LP) was used for in situ measurements. Seven tree species were selected, out of which three are native to Delhi ridge, viz., Vachellia leucophloea, Ficus religiosa and Millettia pinnata and four are non-native, viz., Albizia lebbeck, Prosopis juliflora, Azadirachta indica and Cassia fistula. Our results showed a significant seasonal variation and effect of native and non-native tree species on soil respiration. Soil respiration was high during monsoon and low in winter. The highest annual soil respiration was observed under the canopy of F. religiosa (18.72 µmol CO2 m−2 s−1 year−1) and lowest under A. indica (4.58 µmol CO2 m−2 s−1 year−1). The tree species showed the pattern: F. religiosa > A. lebbeck > P. juliflora > V. leucophloea > M. pinnata > C. fistula > A. indica. Soil respiration showed a positive correlation with soil moisture and temperature (P

Distance runners can approach long descents with slow cadence and long steps, or a fast cadence with shorter steps. These approaches differentially affect mechanical loading and energy demand.This study determined the cadence range in which biomechanical loads, caloric unit cost and energy cost were simultaneously minimized during downhill running (DR).Trained runners (N = 40; 25.6 ± 7.2 yr; 42.5% female) participated in this experimental study. Participants ran on an instrumented treadmill while wearing a portable gas analyzer during six conditions: control normal level running (LR) at 0 deg inclination (CON-0); control DR -6 deg inclinaton (CON-6); DR at cadences +/-5% and +/-10% different from CON-6. A motion analysis system was used to capture running motion, and an instrumented treadmill captured force data. Cardiopulmonary measures, rating of perceived exertion (RPE), and biomechanical measures (temporal spatial parameters, peak ground reaction forces [GRF], vertical average loading rate [VALR], impulses) were calculated. Caloric unit cost and energy costs were standardized per unit distance.Running at -10% cadence increased HR by 10 bpm compared to CON-6 (p 0.0001). Vertical excursion of the center of mass and step length were greatest in the cadence -10% and least in the cadence +10% conditions (both p 0.0001). RPEs were higher among all cadence conditions compared to CON-0 (p 0.0001). Caloric unit costs were lowest in CON-6, and +/5% cadence conditions compared to the CON-0 and +/-10% conditions (-2.1% to -12.3%, respectively; p 0.05). Peak GRF and VALR were not different among conditions; vertical impulses were greatest in the -10% condition compared to CON-0, CON-6 and +5% and +10% by 11.3-14.5% (p .001).Changing cadence across level and downhill stretches is likely not necessary and may actually increase perceived effort of running. Running downhill at cadences that range +/-5% of preferred simultaneously minimize caloric unit cost and impulse loading.

Fuel system, type of fuel and type of spark plug, are the determining variables in producing exhaust gas in motorized vehicles. Pollutants produced by motor vehicle emissions include Carbon Monoxide (CO), carbon dioxide (CO2), Sulfur Dioxide (SO2), Nitrogen Monoxide (NOX), Hydrocarbons (HC), Lead Particles (PB), smoke and ash. These pollutants can cause interference in humans, animals, plants and other objects. The study was conducted to determine the effect of the main variables of the fuel system variables (Carburetor and EFI), type of fuel (Premium octane 88 and Pertamax octane 92) and the type of spark plugs (standard spark plugs and spark plugs Iridium) on CO gas exhaust. The test tool used to determine the value of the percentage of vehicle exhaust is a Gas Analyzer and the test vehicle used is a 4-step motorcycle. The research method uses factorial design and variable analysis using Yates's algorithm. The test results show that the effect of the fuel system is -1,272 (Carburetor), the effect of fuel type is -0,268 (Premium), and the type of spark plug is -0,018 (standard spark plug), so the most influential variable on CO gas output is the fuel system using the Carburetor.

Agricultural wastes generated from palm and coconut shells could be renewable carbon sources in steelmaking by providing the solution to environmental problems and reducing the gas emission. By applying these wastes as carbon reductant at steelmaking’s temperature, the determination of the reduction-controlling reaction rate is necessary. Thus, the present study aims to provide an understanding of the effect of high temperature (1823 K) on the reduction-controlling reaction rate of palm and coconut chars that reacted with steelmaking slag. Palm and coconut shells were pyrolyzed at 723 K under nitrogen inert for char conversion. The char has a porous structure and contains high volatile matter that is more chemically active in the system reaction compared to coke. All carbonaceous materials including coke as a control carbon mixed with steelmaking slag using an infrared (IR) gas analyzer to measure the amounts of carbon dioxide (CO2) and carbon monoxide (CO) gases produced after reduction. The reaction rate of palm and coconut chars after reaction with steelmaking slag was lower (0.93721 × 10−5 and 0.30563 × 10−5 mol cm−2 s−1) than that of coke (2.16283 × 10−5 mol cm−2 s−1) due to lower fixed carbon content that retards the reaction rate. The reaction using palm and coconut chars approached faster the equilibrium of the carbon solution-loss reaction (C + CO2 → 2CO) and Boudouard equilibrium where the reaction reached the equilibrium value of 1.0 than coke due to higher CO generation. The results found that agricultural waste char is used as a carbon reductant in iron oxide reduction of steelmaking slag in a cleaner and sustainable production of iron due to their better properties such as volatile matter and porous structure.

The present study aims in developing an alternative energy solution for compression ignition engine with mixed bio oils from Jatropha and Pongamia (Karanja) vegetable. The high viscosity of the oil was reduced by preheating and transesterification process. The properties of the oil namely viscosity, density, calorific value and flash point were evaluated. The exhaust emissions of a single cylinder diesel engine were examined using 3 hole (3H) and 4 hole (4H) nozzle with 80:20 diesel and biodiesel ratio. The 3H nozzle exhibits the optimum emission levels as per the Indian norms. At no load condition, both 3H and 4H have the emission with same NOX composition while 4H produces more CO2 and least CO and HC. As the load increases the NOX gases emission increases wherein 4H produces more NOX gas than 3H nozzle. CO gas stabilized to 0.01% from the load of 2 kg itself for 4H whilst the 3H nozzle stabilized on 8 kg.

Introduction: Patients with Adolescent Idiopathic Scoliosis (AIS) show reduced exercise capacity during the Incremental Shuttle Walk Test (ISWT). However, we not know how patients behave in the late postoperative (LPO) period. Objective: The aim of this study was to evaluate the ISWT distance (ISWTD) and physiological responses during ISWT in AIS patients during the LPO period. Methods: We included 22 patients with AIS in the LPO period (SG) and 21 adolescents in the Control Group (CG). We assessed pulmonary function (FVC and FEV1). During ISWT, a gas analyzer was used to assess peak oxygen (VO2) and submaximal relations: Oxygen Uptake Efficiency Slope (OUES) and the breathing pattern (ΔVT/ΔlnVE). Results: Significantly lower values were observed in SG: VO2 (22 ± 5 vs. 27 ± 4), ISWTD (567 ± 94 vs.604 ± 86), FVC (2.70 ± 0.47 vs. 3.33 ± 0.52) and FEV1 (2.41 ± 0.46 vs. 2.84 ± 0.52). There were significant correlations between ISWTD and VO2/Kg (r = 0.80); between OUES and ΔVT/ΔlnVE (r = 0.65); and between the main thoracic curve with VO2/Kg (r= −0.61). Conclusion: AIS patients in the LPO period have significantly reduced exercise capacity associated with reduced lung function, residual spinal curve and cardiovascular deconditioning. Level of Evidence III; Prognostic Studies - Investigation of the effect of characteristic of a patient on the outcome of the disease. RESUMO Introdução: Pacientes com escoliose idiopática do adolescente (EIA) têm capacidade de exercício reduzida durante o Incremental Shuttle Walk Test (ISWT). No entanto, não sabemos como os pacientes se comportam no período pós-operatório tardio (POT). Objetivo: O objetivo deste estudo foi avaliar a distância do ISWT (ISWTD) e as respostas fisiológicas durante o teste em pacientes com EIA no período POT. Métodos: Foram incluídos 22 pacientes com EIA no período POT (GCi) e 21 adolescentes no Grupo Controle (GCo). Avaliamos a função pulmonar (CVF e VEF1). Durante o ISWT, foi utilizado um analisador de gases para avaliar o pico de oxigênio (VO2) e as relações submáximas: eficiência da captação de oxigênio (OUES) e o padrão de respiração (ΔVC/ΔlnVE). Resultados: Valores significativos mais baixos foram observados no GCi: VO2 (22 ± 5 vs. 27 ± 4), ISWTD (567 ± 94 vs. 604 ± 86), CVF (2,70 ± 0,47 vs. 3,33 ± 0,52) e VEF1 (2,41 ± 0,46 vs. 2,84 ± 0,52). Houve correlações significativas entre ISWTD e VO2/Kg (r = 0,80); entre OUES e ΔVC/ΔlnVE (r = 0,65) e entre a curva torácica principal com VO2/Kg (r = −0,61). Conclusão: Os pacientes com EIA no período POT tiveram redução significante da capacidade de exercício associada à função pulmonar reduzida, curva residual na coluna vertebral e descondicionamento cardiovascular. Nível de Evidência III; Estudos Prognósticos - Investigação do efeito de característica de um paciente sobre o desfecho da doença. RESUMEN Introducción: Pacientes con escoliosis idiopática del adolescente (EIA) tienen capacidad de ejercicio reducida durante el Incremental Shuttle Walk Test (ISWT). Sin embargo, no sabemos cómo los pacientes se comportan en el período postoperatorio tardío (POT). Objetivo: El objetivo de este estudio fue evaluar la distancia del ISWT (ISWTD) y las respuestas fisiológicas durante la prueba en pacientes con EIA en el período POT. Métodos: Se incluyeron 22 pacientes con EIA en el período POT (GQ) y 21 adolescentes en el grupo control (GC). Se evaluó la función pulmonar (CVF y VEF1). Durante el ISWT, se utilizó un analizador de gases para evaluar el pico de oxígeno (VO2) y las relaciones submáximas: eficiencia de la captación de oxígeno (OUES) y el patrón respiratorio (ΔVC/ΔlnVE). Resultados: Se observaron valores significativos más bajos en el GQ: VO2 (22 ± 5 vs. 27 ± 4), ISWTD (567 ± 94 vs. 604 ± 86), CVF (2,70 ± 0,47 vs. 3,33 ± 0,52) y VEF1 (2,41 ± 0,46 vs. 2,84 ± 0,52). Hubo correlaciones significativas entre ISWTD y VO2/Kg (r = 0,80) entre OUES y ΔVC/ΔlnVE (r = 0,65) y entre la curva torácica principal con VO2/Kg (r = −0,61). Conclusión: los pacientes con EIA en el período POT tuvieron reducción significativa de la capacidad de ejercicio asociada a la función pulmonar reducida, la curva residual de la columna vertebral y la falta de condicionamiento cardiovascular. Nivel de evidencia III; Estudios pronósticos - Investigación del efecto de característica de un paciente sobre el desenlace de la enfermedad.

In the traditional analyzers of the total concentration of combustible gases (a mixture of concentrations of combustible gases), the dependence of the signal value for each component of the mixture is determined by from their concentrations. This signal should be enclosed in the range from 0.5% LEL to 50% of the LEL. The calibration of this analyzer is carried out on some gas that lies within the this range. Usually methane or propane is used for this purpose [1,2]. In the article the possibility of controlling the selectivity of the analysis of gas components by the methods of negative filtration [3] of the useful signal in the optical path of the gas analyzer is considered. There are many analytical tasks for which it is necessary to achieve the same sensitivity to the measured gas components. For example, in the analyzer mentioned above, the total concentration of combustible gases in the air. Indeed, different combustible gases can lead to similar effects and it is not possible to determine the concentration of each. The most common are flammable gases such as methane, butane, propane. Of course, it is desirable that the combustion gas alarm has the same sensitivity to these gases and does not respond to interfering, such as CO2.

The article presents the project of guidelines in perioperative cardio-pulmonary resuscitation by international expert group and analyzes of situation on this subject in Ukraine. According to the annual reports of the anesthetic service of the 20 regions of Ukraine in 2017, 116 cases of cardiorespiratory arrest were recorded in the operating room and during the first postoperative day. 38168 cases of complications were registered in the intraoperative period and during the first day after surgery, 96 (0.25%) of them were fatal. The total number of performed anesthesia during 2017 is 858331. The incidence of intraoperative cardiorespiratory arrest was 1: 7400 anaesthesia, mortality 1: 8940 anaesthesia. Such low incidence are likely to be due to lack of registration and does not reflect a real situation. In Ukraine, the supply of minimum monitoring is 0.46 per 1 operating table. Disastrously missing modern anesthetic equipment, advanced monitoring and equipment for difficult airways. Conducting inhalation anesthesia in the mode of small / minimum flow without a gas analyzer has become, unfortunately, a common practice in Ukraine. Nearly absolutely no monitoring of neuromuscular conduction, depth of anaesthetia.

Engine performance, combustion and emission characteristics of African pear (Dyacrodes edulis) seed oil biodiesel-petrodiesel blends (B25, B50, B75 and B100) tested on four-cylinder, direct-injection (DI), four-stroke, water-cooled Perkins 4:108 diesel engine over varying loads (5 Nm, 10 Nm, 20 Nm, 30 Nm and 40 Nm) and speed range of 1500–3500 rpm is presented. Exhaust emissions were recorded using Bacharach, PCA2 Qs1007 model gas analyzer. Brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), carbon monoxide (CO), oxides of nitrogen (NOx) and hydrocarbon (HC) emissions were optimized as response variables considering load, speed and fuel blend as input variables using Nelder-Mead (NM) simplex method and multiple-input multiple-output artificial neural network (MIMO-ANN) of Levenberg-Marquardt algorithm. Multi layer perception (MLP) network back propagation was applied for non-linear mapping between the input and output variables. The developed ANN and NM models produced less deviations and exhibited high predictive accuracy with high correlation coefficients between 0.90 and 0.99. The values of absolute average deviation (AAD), root mean squared error (RMSE) and standard error of prediction (SEP) for all the responses except NOx were very low. Optimal responses of 38.963% BTE, 0.1096 kg/kW-h BSFC, 0.05% CO, 220.9173 ppm NOx and 20.1524 ppm HC at fuel blend of 69.58, 5.0, 40, 38.35 and 38.22, engine load of 10, 20, 10, 10 and10 Nm and engine speed of 980, 2650, 2000, 2000 and 2000 rpm respectively were established as viable routes for reduced fuel consumption, combustion emissions and high thermal efficiency via the NM approach. For these conditions, experimental values of the responses were found to be BTE of 42.00%, BSFC of 0.0506 kg/kW-h, CO emission of 0.046%, NOx emission of 232.01 ppm and HC emission of 20.703 ppm. The developed models produced the idealized results that are useful for predicting the engine performance and emission characteristics.

Formation of porosity and intermetallic compounds (IMCs) were studied in electron beam welded (EBW) DP-600 steel to Al-5754 dissimilar alloy joints at three different weld conditions such as without beam oscillation, with beam oscillation and with varying beam oscillation diameter. X-ray Diffraction (XRD), scanning electron microscopy (SEM), microhardness, three-dimensional X-ray computed tomography (XCT) were used to characterize porosity and IMCs distribution in these weld joints. Beam oscillation with optimum oscillation diameter (1 mm diameter) improved the weld quality by reducing the amount, maximum size and percentage of pores in weld zone significantly. For IMCs, average size increased little bit but maximum size, percentage of formation and amount reduced. By increasing oscillation diameter (2 mm diameter) beyond optimum value (1 mm diameter), quality of joints was found to deteriorate with accompanying higher pore density, average pore size, average IMCs size etc. Raman spectroscopy and Leco gas analyzer were also used to identify and quantify the entrapped gases in the weld joint.\ud

The article presents a methodology of comprehensive study of thermal radiation emitted by furnace gases during solid fuel combustion. The characteristics of initial fuel and chemical composition of flyash are described. The absorption coefficients of the gaseous phase in relation to the wavelength, temperature, and concentration of the main gas components are measured. The gas composition was determined by calculation of the total combustion products, as well as experimentally (through a gas analyzer). The experimental results on the particle shapes and sizes, the distribution function of flyash particles, the fusibility of mineral part were used to calculate the radiation characteristics of the condensed phase. Calculations of emission characteristics of furnace gases (spectral and integral flux densities and emissivity factors) depending on the influence of each phase at different operating temperatures are presented. The method efficiency is estimated through comparing with calculated and experimental data on the emission characteristics for homogeneous and heterogeneous combustion products. Spectral ranges were chosen to determine the temperature for furnace gases, a plume, and the surface of flyash deposits on the furnace walls. Experimental dependences of the emissivity factors for flyash deposits on temperature are presented. The findings can be used to calculate heat fluxes, for the purposes of furnace gases pyrometry, and to determine the temperature level in the compilation of operational maps for the boiler.

Naugle, KE, Carey, C, Ohlman, T, Godza, M, Mikesky, A, and Naugle, KM. Improving active gaming's energy expenditure in healthy adults using structured playing instructions for the Nintendo Wii and Xbox Kinect. J Strength Cond Res 33(2): 549-558, 2019-Professionals work constantly to increase energy expenditure and improve cardiovascular outcomes. A newer form of physical activity used to improve cardiovascular outcomes and increase energy expenditure while also providing entertainment is active gaming. The purpose was to determine energy expenditure and enjoyment levels during participation in different games played with a directed set of instructions designed to enhance movement. Twenty-one adults completed 6 sessions (1 familiarization and 5 experimental) on separate days. During 4 of the experimental sessions, participants played 1 of 4 active games for two 15-minute periods. Two active games were from Xbox Kinect and 2 were from Nintendo Wii. During the first period, participants played at a self-selected level of activity. During the second period, participants were given specific instructions for play during both active and down times within games. Participants wore a portable gas analyzer to measure energy expenditure. Resting energy expenditure was measured during session 6. Outcome measures were analyzed with 4 Game × 2 Period repeated-measures analyses of variance. Energy expenditure, measured in metabolic equivalents (METS), was greatest while playing Kinect Fighter Within. METS, enjoyment levels, and percentage of time spent in whole-body activity were greater during the period with specific instructions compared to the self-selected levels of activity, regardless of active game. When played at a self-selected level of activity, energy expenditure during the active games was similar to that of light physical activity. However, energy expenditure improved during the second period of game play showing that specific instructions created energy expenditure of moderate intensity.

Background The validity of Actiwatch 2 in assessing sleep was evident, but its validity in assessing physical activity (PA) level was unknown. Research question The objective of this study was to validate the wrist-worn Actiwatch 2 and ActiGraph wGT3X as a measurement of PA level against energy expenditure measured by indirect calorimetry. Methods Twenty-seven university students aged 18–26 were recruited from July 2016 to May 2017. They were instructed to run at different speeds (4, 6, 8, 10, and 12 km/h) on a treadmill, each speed for 10 min. Oxygen consumption and carbon dioxide production of the subjects was measured by indirect calorimetry using the Cosmed K4b2 gas analyzer. Each subjects wore a single pair of accelerometers (Actiwatch 2 and ActiGraph wGT3X) on both wrists. Results All the accelerometers were strongly correlated (ρ=0.83-0.94, all p-values 75%. When classifying the activities as either sedentary, light activity, moderate-intensity activity, or vigorous-intensity activity using the MET prediction equations, the agreements between the four accelerometers and that by the Cosmed K4b2 were high, all AUCs were above 80% except those of the Actiwatch worn on the left (non-dominant) wrist. The Bland-Altman plots show that, for all four accelerometers, the biases were close to zero and error variances were largest when the mean measurements were around 6 METs. Significance We showed that wrist-worn Actiwatch 2 and ActiGraph wGT3X-BT were strongly correlated in PA assessment.

The present study deals with application of ethanol and manganese oxide nano-particle at different ratios to gasoline-fueled SI EF7 engine. The blends are prepared in three emulsions namely gasoline-10%ethanol, gasoline-10%ethanol-10ppmMn2O3, and gasoline-10%ethanol-20ppmMn2O3. In order to prevent the amalgamation of nanoparticles and sedimentation during the test, the ultrasonic cleaner device is utilized to ensure the homogeneity of the composition. To measure the engine power, a 190 kW eddy current dynamometer is coupled and for determination of engine out exhaust gas, AVL gas analyzer is used. The results indicate that ethanol addition by 10% lead to 2.6% increase in brake power (BP), but interestingly 10 ppm Mn2O3 nano-additive raise the BP to 14.38% and 20 ppm nano-additive led to 19.56% increase of BP. With regard to emissions, ethanol presence in the blend reduces CO and UHC and raises the NOx and CO2 because the abundant oxygen bonds in ethanol help oxidation process. The best blend in terms of UHC and BSFC reduction is gasoline-10%ethanol-20ppmMn2O3. The results also revealed that the peak of CO and UHC occurs at 75 N.m since at 75 N.m the inlet valve is actuated and the excess air is inducted to cylinder.

Compound jet fire extinguishing technology is an efficient technology for oil fires. The hydrophobic ultrafine dry powder is used for the solid phase in the compound jet, but it can't be supplied continuously due to the insufficient supply of compressed nitrogen. Thus, the feasibility of using the compressed air to replace the compressed nitrogen in the compound jet was explored. The key factor for the replacement, which influences the fire extinguishing efficiency, is the oxygen content in the contact point between the jet and the flame. Firstly, the oxygen content of the ultrafine powder jet driven by air or nitrogen were investigated by gas analyzer; Secondly, 150 L (liter) gas oil and 50 L water were put in a oil pan, the compared fire extinguishing experiments were conducted, the fire extinction time and the temperature drop range were investigated. In order to reveal the effect of ultrafine dry powder on oxygen content in gas jet, the experiment that spray the compressed nitrogen were conducted. The results show that there are not much differences for the two gases in extinguishing the pool fire, indicating that compressed air as the driving gas of the compound jet is feasible during fire extinguishing process.

The aim of the study: to reveal morpho-functional changes in erythrocytes in students with different levels of general endurance. Material and methods: It was examined 80 students (17-19 years old). The students performed a 12-min shuttle run (20m endurance shuttle-run - bleep test). The ventilation function of the lungs was estimated according to the forced exhalation data. The gas composition of the blood was determined by the gas analyzer ОРТІ ССА-TS. Results. It was determined that in students with lower than average and low levels of general endurance, the increase of lungs ventilation is stipulated by the increase in the frequency of respiration. This leads to rapid tiredness of the respiratory muscles, reduces ventilation of the lungs and gas exchange. Low levels of blood oxygenation, intensity of oxidative phosphorylation and ATP resynthesis lead to the appearance of atypical forms of erythrocytes. It is established that at the low level of cardiorespiratory endurance there is an increase in the concentration of acidic metabolism products in arterial blood and reduce in its alkaline reserves. Conclusions. Students with below average and low levels of physical fitness are characterized by: increased respiratory rate, reduced ventilation of the lungs and gas exchange. This leads to the formation of a hypoxic condition in the peripheral blood: a reduce of pO2, pCO2 level and the appearance of metabolic acidosis symptoms. For students with below average and low level of physical fitness hypoxic condition leads to violation of bioenergetic processes in peripheral blood erythrocytes, reduction of ATP product, increase in the content of intra-erythrocytic 2,3-BPG.

From kitchen and dining place lots of food wastes are generated and these create many problems if these are disposed directly by dumping. Instead of dumping, the aforesaid wastes can be utilized in a better way to produce valuable products such as biogas. In the open literature, different methodologies of digestion by using bacteria or microorganisms have been described. The use of bacteria or microorganism increases the cost of conversion. However, the literature does not disclose any information on the process which describes the digestion of the food waste without the use of microorganism directly. Hence, in the current work, an attempt has been made to digest food waste and to produce biogas by using a novel technique which does not use the bacteria directly. In the current work, nourishment waste was gathered from various messes of National Institute of Technology Rourkela and these were given as the feedstock to our reactor which functions as an anaerobic digester framework to deliver biogas. For the production of biogas, food waste was mixed with cow dung at different ratios and the cow dung acts as an inoculum in the current case as it contains both methanogenic and acid-forming bacteria. By using a gas analyzer, after experimentation, the composition of the gas was analyzed and the achieved composition confirms that the obtained gas is the biogas. The result shows that the rate of biogas production is influenced by the pH, temperature and solid-to-water ratio. The biogas production rate is found to be maximum at an intermediate solid-to-water ratio of 1:2 and at the neutral range of pH. Furthermore, the biogas production rate increases from 110 to 142 ml with the rising temperature from 25 to 40 °C, and with the further increment in temperature, the methane production rate declines. In addition to the above, the process behavior at different conditions has been modeled by using response surface methodology technique and also the optimum conditions (T = 44.03 °C, R = 0.44 and pH 7.02) for the maximum production of biogas has been determined.

In order to produce a clean and trouble-free biodiesel that will represent true alternative to fossil diesel, this work evaluates the performance of a multi feedstock plant for biodiesel production. The performance evaluation of the developed plant was conducted using used frying oil and palm olein oil using acid and alkali transesterification process respectively. Prior to that, the feedstock characterization in terms of moisture content and the amount of free fatty acid in the used and unused oils were determined. The biodiesels produced were characterized and its properties compared in respect of the American Society for Testing and Materials (ASTM D6751) and EN 14214 limits for biodiesel. Also, emissions of some pollutants from the diesel engine were measured at 2000 rpm using the AUTOplus gas analyzer for diesel and blends of biodiesel. Results obtained indicates that the developed plant can transesterify used and unused vegetable oil to biodiesel and can also undertake both alkali-catalysed and acid-catalysed transesterification.

The flame behavior of acoustically excited combusting swirling double-concentric jets with a dual-disk flow controller at the jet exit was experimentally studied. The fluids for the central and swirling jets were propane and air, respectively. The central jet was acoustically excited using a loudspeaker. The central jet velocities were measured with a one-component hot-wire anemometer to estimate the acoustic excitation behavior. Close-up and full-length short-exposure and time-averaged flame images were captured using traditional photography techniques. The flame temperatures were measured using a homemade L-shaped fine-wire thermocouple. The combustion product concentrations were measured using a gas analyzer. Three characteristic flame modes—yellow-base anchored flame, blue-base anchored flame, and lifted flame—were observed in the domain of the excitation Strouhal numbers and jet pulsation intensities. The lifted flame was blue, very short, highly turbulent, even at low Reynolds numbers, and difficult to blow out. The flame length was significantly reduced, and the flame temperatures were drastically increased when the combusting jets were forced into the characteristic modes of blue-base-anchored and lifted flames. The concentrations of unburned hydrocarbon, carbon monoxide, and nitric oxide fell to negligibly small values. The acoustic excitation was effective in promoting the combustion performance of the swirling double-concentric jet flames.

The aim of this study was to develop a methodology to measure the rates of air infiltration into refrigerated compartments based on the tracer gas dilution technique. An experimental apparatus was designed and constructed especially for this purpose. The apparatus includes a means of distributing the tracer gas uniformly into the zone, a means of ensuring a uniform concentration both in the vertical and horizontal directions, a means for obtaining the air samples, and a gas analyzer to measure the gas concentration at known times. Concentration measurements were taken using the infrared photoacoustic spectroscopy technique. Tests were carried out on three distinct refrigerators, with the compressor on and off, and with the concentration decay and constant concentration measurement techniques. It was observed that the tests have a high level of repeatability, with deviations of less than 5% in the air infiltration rate measurements. In addition, adsorption tests were carried out and the results indicated that the adsorption of the tracer gas by the refrigerator materials and gasket is insignificant when compared to the concentration variations caused by air infiltration. To verify that the technique developed is reliable and practical and that it represents a useful tool for the design and analysis of household refrigerators, two new refrigerators were tested. The tests were performed with different gaskets and extra seals in key regions. The results for the variation in the air infiltration were found to be reliable and the technique is practical to apply.

En el presente estudio se determina el rendimiento de un motor ciclo Otto, utilizando gasolina Súper (92 octanos), Extra (87 octanos) y mezclas con estas dos gasolinas, la primera con 50%V de cada tipo, mientras que la segunda con un valor en volumen de 70% de Súper con 30%V de Extra. Se utilizó un dinamómetro para obtener las curvas de potencia y torque, la mezcla Súper 50%V con Extra 50%V obtuvo un mayor valor de potencia con 81.3 HP, la gasolina Súper obtuvo un mayor valor de torque con 89.2 lb-ft. Con las pruebas dinámicas en ruta se midió el consumo de combustible, resultando menor el consumo con la gasolina Súper. Mediante pruebas dinámicas con el equipo ASM y un analizador de gases, se midieron las emisiones de gases contaminantes (CO, CO2, HC y NOx). En el ciclo ASM 2525 se midió CO, HC y NOx siendo la gasolina Súper, Extra y la mezcla Súper 50%V con Extra 50%V respectivamente las menos contaminantes y en el ciclo ASM 5015 siendo la gasolina Súper, Extra y la mezcla Súper 70%V con Extra 30%V respectivamente las menos contaminantes. En la prueba estática de gases, las emisiones bajas resultaron con la gasolina Súper.

Continental greenhouse gas monitoring networks extensively use tall towers for higher spatial representativeness. In most cases, several intakes are built along the tower to give information also on the vertical concentration profile of the components considered. Typically, a single gas analyzer is used, and the intake points are sequentially connected to the instrument. It involves that the continuous concentration signal is only sampled for discrete short periods at each intake point, which does not allow for a perfect reconstruction of the original concentration variation. It increases the uncertainty of the calculated hourly averages usually used by the atmospheric transport and budget models. The purpose of the study is to give the data users an impression of the potential magnitude of this kind of uncertainty, as well as how it depends on the number of intakes sampled, on the length of the sampling period at each intake, on the season, and on the time of the day. It presents how much improvement can be achieved using linear or spline interpolation between the measurement periods instead of the simple arithmetic averaging of the available measurements. Although the results presented here may be site-specific, the study calls attention to the potentially rather heterogeneous spatial and temporal distribution of the uncertainty of the hourly-average concentration values derived from tall-tower measurements applying sequential sampling.

The technology for identifying and classifying environmental gas content plays an important role in the design of incident detection systems (the presence of hazardous concentrations of gas mixtures and their types in the environment) based on the signals from gas analyzer systems. To improve the quality and reduce the time of the effective recognition of environmental gas contamination, this study uses processing based on artificial neural networks (ANN) of signals observed from gas analyzing systems. The paper investigates the influence of ANN and machine learning for determining the concentrations of gases, combustible impurities and their type. The results show that the use of ANN gas analyzer systems for processing sensor signals, which have a competitive layer with feedback in their structure, can significantly improve the quality of the recognition and classification of the concentrations of gas mixtures in the environment. Testing the ANN architectures was carried out on data from a semiconductor sensor of a gas-analyzer system when exposed to explosive gases. The results of identifying the gas type and its concentrations in the combustible mixture for each type of ANN architecture are given, the errors and recognition quality of the types of hazardous gas mixtures are compared. In the experiments on real data, different ANN architectures were compared and their effect on the efficiency of hazardous gas detection. The neural network model proposed in the study, with the addition of feedback and a delay line in the competitive layer of the ANN structure, made it possible to significantly increase the efficiency of identifying the gas and determining its concentration in the environment. The ANN model, and its software implementation, contributes to the development of a system for monitoring gas pollution in the environment.

The emission of harmful elements from burning building ceiling materials and their attendant health effects on inhabitants within the vicinity of the emitted harmful elements is increasingly becoming a source of concern globally. Hence, the need to develop eco-friendly flame-retardant composite materials suitable for house ceiling purposes to forestall unwanted toxic emissions. This work identified the chemical structure of developed composite products and their emission performance during combustion. X-ray Diffraction (XRD) analysis was used for phase quantification and E550 combustion gas analyzer for emission characterization of the developed composites. Thermolyne 950 °C oven was employed for the combustion analysis of the prepared composite at 500 °C. Quasi negligible SO2 and CO2 levels existed, while A4, 0.3Aldr0.23Cmt0.3Si0.05G0.12CS recorded maximum CO level, indicating toxic affluence. The low mass losses of all composite materials, especially for A2, 0.6Aldr0.34Cmt0.05G0.01OBSretard significantly due to its activities by the retardant constituent. The flame retardant nature of all produced composites was evidenced in their elemental composition. There was an absence of a flammable element and stable insulating compounds providing retardance to flame occurrences. These suppressions in flame inclination of the reinforced materials were noticed within the boundaries of the ceiling crystals from the structural examination. The intermetallic phase from the diffraction intensities showed the presence of a significant second bond interstitial solid-phase across the matrix, especially for 0.6Aldr0.34Cmt0.05G0.01OBS ceiling material. This study has established the eco-friendliness of developed building ceiling composite and the potential to reduce the importation of building ceilings. The developed ceiling composite evidently demonstrated high potential to compete favourably with imported ceiling materials in terms of fire resistance performance, low cost of production, and abundant availability of raw materials in the environment. Oil beanstalk is a novel material introduced as a reinforcement to developed building ceiling composite. This research provides a blueprint for manufacturers, construction and allied industry, and stakeholders in developing eco-friendly flame retardant composite ceilings whose materials can be readily sourced locally available in the environment.

The heavy-duty diesel engine is used in the main transportation vehicles in Korea to deliver products from various companies, however, diesel engines produce enormous quantities of nitrogen oxide (NOx), which harms human health. The selective catalytic reduction (SCR) system is a common solution to reduce NOx emissions from diesel engines, however, heavy-duty diesel engines produce more NOx than can be dealt with using an SCR and thus require investigations into effective NOx reduction solutions. This study investigated 12,000 cc heavy-duty diesel engines from Hyundai using the 1000 rpm engine operation to produce 1330 ppm of NOx emission. The ammonia generation process was assessed by the amount of ammonia produced, the amount of ammonia gas was identified by 19 gas sensors on the catalyst surface, the effectiveness of the mixing process between the ammonia and the NOx in the system was determined by the NOx conversion values from a gas analyzer. Comparison between the experiment and simulation results shows the ammonia and NOx values and elucidates the temperature results for vaporization and saturation quantity, ammonia distribution, and NOx conversion in the system. The NOx conversion investigations also provide the chemical reaction and numerical equation relevant to the ammonia and NOx distribution.

Anaerobic digestion for treatment of swine wastewater is an attractive alternative, among other aspects, for the generation of biogas. This gas is composed predominantly of methane and can be converted into electrical and thermal energy. However, the knowledge of the biogas composition is of paramount importance, especially regarding the methane content due to its energetic properties. The alternatives for this determination usually require high cost and specialized technicians. Therefore, the search for simple and low cost alternative solutions and techniques can improve the biogas use as an energy source and favor energy sustainability in pig farming. The present study aimed to compare the results of the methane composition of a portable analyzer with that of a Gasboard gas analyzer. The biogas was collected and characterized in a full cycle swine farm from January to December 2019 in the municipality of Teixeiras (MG), Brazil. The methane composition values did not differ statistically for a 5% significance level between the evaluated methods. The use of the portable kit is a simple and low cost alternative in determining the methane content in biogas and can be used reliably.

Building on our previous development of a compact, portable, and low SWaP gas analyzer (11” x 6.7” x 5.1”, 7.8 lbs) based on photoacoustic spectroscopy and using broadband quantum cascade laser arrays, we demonstrate here compositional analysis of airborne aerosols using this instrument. With an integration time of 330-ms per laser, and ~70 seconds for a spectrum covering 950-1500 cm-1, our instrument showed a detection sensitivity at the mg/m3 level for solid and liquid-loaded solid aerosols. Additionally, Malathion-loaded aerosols can be discriminated from pure Syloid aerosols based on their absorption features. The preliminary results show a potential path for developments of a portable real-time aerosol composition analyzer.

Use of leaf gas exchange measurement enhances the characterization of growth, yield, physiology, and abiotic stress response in grapevines. Accuracy of a crop response model depends upon sample size, which is often limited due to the prolonged time needed to complete gas exchange measurement using currently available infra-red gas analyzer systems. In this experiment, we measured mid-day gas exchange of excised and in situ leaves from field grown wine grape (Vitis vinifera) cultivars. Depending upon cultivar, we found measuring gas exchange on excised leaves under a limited time window post excision gives similar accuracy in measurement of gas exchange parameters as in situ leaves. A measurement within a minute post leaf excision can give between 96.4 and 99.5% accuracy compared to pre-excision values. When compared to previous field data, we found the leaf excision technique reduced time between consecutive gas exchange measurements by about a third compared to in situ leaves (57.52 ± 0.39 s and 86.96 ± 0.41 s, for excised and in situ, respectively). Therefore, leaf excision may allow a 50% increase in experimental sampling size. This technique could solve the challenge of insufficient sample numbers, often reported by researchers worldwide while studying grapevine leaf gas exchange using portable gas exchange systems under field conditions.

Synthesis of multi-function flame retardants is widely increasing to fulfil industrial and economic goals. In this work, a novel flame retardant, melamine salt of tannic phosphate (MTP) was prepared and characterized. MTP was mixed with polyvinyl alcohol (PVA) solution and used as a coating for cotton fabrics. In addition, tannic acid (TA) and melamine phosphate (MP) were mixed with PVA solution and applied as a coating for cotton fabrics. Vertical and horizontal flammability tests showed that the flame did not propagate in samples treated with PVA/MTP. In contrast, samples treated with PVA/TA/MP burnt completely. Limiting oxygen index (LOI) data indicated that samples treated with PVA/30%MTP reached LOI value 68.4%, while control sample had LOI value 17.1%. Smoke density results presented that PVA/MTP succeeded in reducing the maximum specific optical density (Ds max) of cotton fabrics. FTIR gas analyzer results manifested that addition of PVA/MTP to cotton fabrics decreased the emission of CO, CO2, C3H8, C2H6, C6H14 and formaldehyde in the gas phase. Fractional effective dose (FED) and lethal toxic potency (LC50) showed that samples coated with PVA/MTP are less toxic than blank. In addition, these fabrics exhibited a remarkable antibacterial property against gram-positive and gram-negative bacteria.

Objectives: The aim of this descriptive study was to characterise anthropometric variables, aerobic capacity, running performance and energy intake and expenditure of hill runners in free-living conditions, and to investigate the relationship between age, anthropometric variables, aerobic capacity and running performance.Methods: Twenty-eight hill runners participated in this study (17 males and 11 females; aged 18–65 years). Body fat percentage estimate, sum of eight skinfolds (triceps, subscapular, biceps, iliac crest, supraspinale, abdominal, front thigh and medial calf) and maximal oxygen capacity (VO2max) were assessed in a laboratory setting. Participants also completed a timed hill run (Dumyat Hill, Scotland, ascent: 420 m, distance: 8 km) while wearing a portable gas analyzer to assess oxygen consumption (VO2). Energy intake and energy expenditure were assessed in free-living conditions over three consecutive days different from the testing days through self-reported food diaries and accelerometers.Results: VO2max assessed in the lab (51.2 ± 7.6 ml·min−1·kg−1) showed a weak negative relationship with age [rs(23) = −0.38, p = 0.08]. Neither body fat percentage (median 12.4; IQR 10.1–17.1) nor the sum of skinfolds (median 81.8; IQR 62.4–97.8 mm) correlated with age [rs(28) = 0.001, p = 0.10 and 26 rs(28) = −0.02, p = 0.94, respectively]. The observed intensity of the hill run was 89 ± 6% of the age predicted maximum heart rate and 87 ± 9% of the VO2max observed in the lab. Hill running performance correlated with VO2max [r(21) = 0.76, p < 0.001], age [rs(26) = −0.44, p = 0.02] and with estimated body fat percentage and sum of skinfolds [rs(26) = −0.66, p < 0.001 and rs(26) = −0.49, p = 0.01, respectively]. Energy intake negatively correlated with age [rs(26) = −0.43, p = 0.03], with the overall energy intake being significantly lower than the total energy expenditure (2273 ± 550 vs. 2879 ± 510 kcal·day−1; p < 0.001; d = 1.05).Conclusion: This study demonstrated that hill running performance is positively associated with greater aerobic capacity and negatively associated with increases in adiposity and age. Further, the study highlights that hill runners are at risk of negative energy balance.