908 resultados para exhaust hood
Resumo:
Non-typable Haemophilus influenzae (NTHi) is a Gram negative pathogen that causes acute respiratory infections and is associated with the progression of chronic respiratory diseases. Previous studies have established the existence of a remarkable genetic variability among NTHi strains. In this study we show that, in spite of a high level of genetic heterogeneity, NTHi clinical isolates display a prevalent molecular feature, which could confer fitness during infectious processes. A total of 111 non-isogenic NTHi strains from an identical number of patients, isolated in two distinct geographical locations in the same period of time, were used to analyse nine genes encoding bacterial surface molecules, and revealed the existence of one highly prevalent molecular pattern (lgtF+, lic2A+, lic1D+, lic3A+, lic3B+, siaA−, lic2C+, ompP5+, oapA+) displayed by 94.6% of isolates. Such a genetic profile was associated with a higher bacterial resistance to serum mediated killing and enhanced adherence to human respiratory epithelial cells.
Resumo:
Using a sampling method of particulate matter (PM) without the use of a dilution tunnel allows for evaluations of the volatile hydrocarbons (HC) in the emissions of diesel cycle engines. The procedure in this work applied a heated filter with temperature controlled. The volatile compounds are condensed at low temperature, allowing for evaluation of the HC by thermal desorption of the PM and for analysis of the condensed compounds of the exhaust gases.
Resumo:
Tämä diplomityö on osa FCEP hankeen Lappeenrannan teknillisessä yliopistossa tehtävää tutkimusta polttomoottoreiden energiatehokkuuden parantamisesta. Työn tavoitteena on saada tutkimustietoa polttomoottoreiden hukkalämpövirtojen hyödyntämisestä sähköntuotannossa. Tavoitteena on kartoittaa polttomoottorin hukkalämpövirtojen sähköksi muunnon potentiaalia valituilla menetelmillä ja tekniikoilla. Työssä tarkasteltavaksi moottoriksi valittiin DF- monipolttoainemoottori. DF-moottorin polttoaineena voidaan käyttää joko kaasua tai polttoöljyä. Laskennat suoritettiin moottorin valmistajan antamien hukkalämpövirtojen arvojen ja moottorin lämpötaseen avulla. Laskennan perusperiaatteena oli vesihöyryprosessin ja ORC-prosessien vertailu pakokaasulämmön hyödyntämisessä sekä matalalämpöisten hukkalämpövirtojen hyödyntäminen ORC-prosesseilla. Lisäksi työssä tutkittiin korkealla painesuhteella ja korkealla hyötysuhteella toimivan turboahtimen vaikutusta hukkalämpövirroista saatavaan tehoon. Diplomityössä tarkasteltiin moottorin lämpötaseen mukaisten arvojen lisäksi moottorin parametrien muuttamisen vaikutusta hukkalämpövirroista saatavaan tehoon. Moottorin parametrien muuttamisen vaikutusta moottorin akselitehoon tai moottorin lämpötaseeseen ei kuitenkaan tämän tutkimuksen puitteissa tarkasteltu. Työssä saatiin arvokasta tietoa polttomoottoreiden hukkalämpövirtojen muuntamisesta sähköksi eri menetelmillä sekä moottorin energiatehokkuuden parantamisesta.
Resumo:
O gênero Orius Wolff é composto por espécies de percevejos predadores, principalmente de tripes, encontradas em muitos ecossistemas naturais e manejados. Entretanto, as interações que podem ocorrer entre esses predadores e suas presas no mesmo "habitat" não são bem conhecidas entre as espécies das regiões tropicais. Este estudo teve como objetivo registrar a interação de espécies de Orius e de tripes coletadas na mesma planta, ou seja, presentes no mesmo "habitat". As coletas foram feitas em várias plantas cultivadas, no campo e em casas de vegetação e em plantas invasoras. A forma e o grau de associação entre as espécies foram determinados, utilizando-se o coeficiente de Spearman (R), calculado com dados de presença/ausência das espécies (Orius e tripes) no mesmo "habitat". Orius insidiosus (Say) foi encontrado associado positivamente aos tripes Frankliniella sp., Neohydatothrips sp. e Haplothrips gowdeyi (Franklin) e negativamente associado a Frankliniella schultzei (Trybom) e Caliothrips phaseoli (Hood). Orius thyestes Herring e Orius sp1 ocorreram simultaneamente em 10 espécies de tripes sem, contudo, apresentar associação significativa, enquanto Orius perpunctatus (Reuter) esteve associado positivamente às espécies Frankliniella sp. e Neohydatothrips sp. e, negativamente, a Frankliniella gemina (Moulton).
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This work is a study of the implementation of a classical controller using a tuning method referred to as IMC (Internal Model Control) and aimed at the reduction of electrical energy consumption by the appropriate relation between energy consumption and the cooling time with forced air. The supervisory system installed was able to manipulate the variable of frequency of the signal power of the exhaust fan engine (forced air module), to accelerate or decelerate the loss of heat from the product to be cooled by airflow variation that passes through the mass of the produce. The results demonstrated a reduction in energy consumption from 64% and an increase of only 8% in the cooling time to the system using PI/IMC (Proportional - Integral with IMC) tuning method compared with the system in its operating nominal condition. This PI/IMC control may be implemented directly in a frequency converter, without the need to purchase a computer or PLC (programmable logic controller) to run the dedicated application, increasing its economical viability.
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This study was conducted to evaluate and compare the behavior of the heating inside poultry shed through gas hood and underfloor heating. The experiment was conducted in poultry shed belonging to the Federal Institute of Education, Science and Technology of Triângulo Mineiro Region, Uberlândia city  state of Minas Gerais (MG), Brazil. The dimensions of the shed are 24 meters long and 9.6 meters wide and with a ceiling height of 3.2 meters. The temperature was measured with an optical thermometer of Minipa brand, MT 350 model. It was used, to the analysis of temperature behavior, the public domain software FEMM 4.2, which uses finite elements techniques, with data collected from two lots. Underfloor heating is made using hot water flowing through a serpentine type system, which is installed below the bed; this hot water is from solar heaters. An energetic and economic assessment of the warming shed for raising chickens was realized. From the results obtained with the simulations, it may observe that the heating through the floor provides a more homogeneous distribution of temperature when compared with the hood heating. The flow of heat is upwards supplying, thus, the greatest need of heating of the bird, which is the pectoral part.
Resumo:
Työn tavoitteena oli selvittää liikennebiokaasuntuotannon ja käytön vaikutus liikenteen ulkoi-siin kustannuksiin Pohjois-Karjalassa. Biokaasua tuotetaan Joensuussa Kuhasalon jäteveden-puhdistamolla sekä Kontiosuon jäteasemalla, Kiteellä biokaasua tuotetaan BioKympin yh-teismädätyslaitoksessa. Lisäksi laskennassa huomioitiin yhden maatilakokoluokan biokaasun-tuotanto. Työssä selvitettiin kaksi skenaariota liikennebiokaasun tuotantomääräksi vuodelle 2015. Liikennebiokaasua voitaisiin tuottaa optimiskenaarion mukaan 3 426 MWh ja maksimi-tuotantoskenaarion mukaan 21 532 MWh. Liikennebiokaasun käytön vaikutukset liikenteen päästöihin laskettiin vuodelle 2015 ja vuo-delle 2020, jolloin liikennebiokaasua käytettäisiin 10 % liikenteen energiantarpeesta Pohjois-Karjalassa. Hiilidioksidipäästöt vähenevät vuoden 2020 tilanteessa samassa suhteessa kuin liikennebiokaasu korvaa fossiilisia polttoaineita. Muista päästöistä merkittävimmät päästövä-hennykset saatiin kun vuoden 2010 dieselautot muutettaisiin biokaasuautoiksi, tällöin hiuk-kaspäästöt alenisivat jopa 18 % vuoden 2010 päästöistä. Lisäksi selvitettiin liikenteen päästöjen pienenemisen vaikutus liikenteen aiheuttamiin ulkoisiin kustannuksiin. Laskettavat ulkoiset kustannukset olivat ilmastonmuutos, pakokaasupäästöt sekä energiariippuvuus. Pakokaasupäästöjen aiheuttamat ulkoiset kustannukset olivat vuonna 2010 noin 7 miljoonaa euroa. Liikennebiokaasua käyttävästä ajoneuvotyypistä riippuen ulkoiset kustannukset laskevat vuoden 2020 tilanteessa 10–16 % vuoden 2010 kustannuksista. Ilmastonmuutoksen ulkoiset kustannukset vuodelle 2010 olivat 9,5 miljoonaa euroa. Biokaasun käytön avulla kustannuksissa voitaisiin säästää 910 000 euroa vuonna 2020. Ener-giariippuvuuden hinta öljynkäytöstä oli vuonna 2010 noin 4,2 miljoonaa euroa ja vuonna 2020 kustannukset voisivat laskea 450 000 euroa.
Resumo:
Tämä diplomityö on osa Lappeenrannan teknillisessä yliopistossa tehtävää tutkimusta polttomoottoreiden energiatehokkuuden parantamisessa. Työn tavoitteena on saada tutkimustietoa polttomoottoreiden hukkalämpövirtojen hyödyntämisestä sähköntuotannossa. Tavoitteena on muodostaa näkemys Mikro-ORC energiamuuntimen mahdollisuuksista ja reunaehdoista osana työkoneluokan (150 kW… 400 kW) dieselmoottorikokonaisuutta, erityisesti maataloussektorilla. Työssä tarkasteltaviksi moottoreiksi valittiin kaksi eri AGCO Sisu Powerin dieselmoottoria. Laskennat suoritettiin moottorin valmistajan antamien hukkalämpövirtojen arvojen perusteella. Laskennan perusperiaatteena oli tutkia ORC-prosessin tuottamaa lisäsähkötehoa hyödyntämällä pakokaasujen lämpöenergiaa korkea-, keski- ja matalalämpötiloissa. Työssä vertailtiin kahden eri kiertoaineen prosessihyötysuhdetta, saatava sähkötehoa sekä prosessin sisäisiä parametreja. Lisäksi työssä tutkittiin ORC-prosessin laskentaa suunnittelupisteessä (design) ja suunnittelupisteen ulkopuolella (off-design), prosessisuureiden optimointia ja lämmönsiirtimien mitoitusta. Diplomityössä tarkasteltiin moottorin energiataseen mukaisten arvojen lisäksi moottorin parametrien muuttamisen vaikutusta hukkalämpövirroista saatavan tehoon. Työssä saatiin arvokasta tietoa polttomoottoreiden hukkalämpövirtojen muuntamisesta sähköksi ORC:lla sekä moottorin energiatehokkuuden parantamisesta.
Resumo:
O presente trabalho, conduzido durante o ano agrícola de 1979/80 na Estação Experimental Agronômica de UFRGS, em Guaíba, RS, apresentou como objetivo testar quatro cultivares de soja (Paraná, Prata, Hood e IAS-4) quanto à sua habilidade em concorrer com Euphorbia heterophylla L. (leiteira, amendoim-bravo) estabelecida em três densidades (0, 12 e 54 plan-tas/m2, em média) e dois períodos de duração da competição (45 e 115 dias após a emergência da soja). Constatou-se que houve redução no rendimento de grãos de soja por efeito dos dois períodos de competição e das densidades de E. heterophylla L. referidas. Também os números de grãos e de legumes por área foram consideravelmente reduzidos pela presença da planta daninha associada ao período mais prolongado de competição. A espessura do caule e o número de nós das plantas de soja decresceram apenas sob o efeito da maior densidade da Euphorbia; entretanto, o número de ramos e o índice de área foliar, este aos 75 dias após a emergência da cultura, sofreram redução com a infestação de 12 plantas de Euphorbia por m2.
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Waste has been incinerated for energy utilization for more than a hundred years, but the harmful emissions emitted from the incineration plants did not begin to cause concern until the 1980s. Many plants were shutdown and the waste incineration plant in Kyläsaari Helsinki was one of them. In later years, new landfill regulations have increased the interest in waste incineration. During the last year, four new plants were taken into operation in Finland, Westenergy in Vaasa among them. The presence of dust has been observed indoors at Westenergy waste incineration plant. Dust is defined as particles with a diameter above 10 μm, while fine particles have a diameter smaller than 2.5 μm, ultrafine under 0.1 μm and nanoparticles under 0.05 μm. In recent years, the focus of particle health research has been changed to investigate smaller particles. Ultrafine particles have been found to be more detrimental to health than larger particles. Limit values regulating the concentrations of ultrafine particles have not been determined yet. The objective of this thesis was to investigate dust and particles present inside the Westenergy waste incineration facility. The task was to investigate the potential pollutant sources and to give recommendations of how to minimize the presence of dust and particles in the power plant. The total particle number concentrations and size distributions where measured at 15 points inside the plant with an Engine Exhaust Particle Sizer (EEPS) Spectrometer. The measured particles were mainly in the ultrafine size range. Dust was only visually investigated, since the main purpose was to follow the dust accumulation. The measurement points inside the incineration plant were chosen according to investigate exposure to visitors and workers. At some points probable leakage of emissions were investigated. The measurements were carried out during approximately one month in March–April 2013. The results of the measurements showed that elevated levels of dust and particles are present in the indoor air at the waste incineration plant. The cleanest air was found in the control room, warehouse and office. The most polluted air was near the sources that were investigated due to possible leakage and in the bottom ash hall. However, the concentrations were near measured background concentrations in European cities and no leakage could be detected. The high concentrations were assumed to be a result of a lot of dust and particles present on surfaces that had not been cleaned in a while. The main source of the dust and particles present inside the waste incineration plant was thought to be particles and dust from the outside air. Other activities in the area around the waste incineration facility are ground work activities, stone crushing and traffic, which probably are sources of particle formation. Filtration of the outside air prior entering the facility would probably save personnel and visitors from nuisance and save in cleaning and maintenance costs.
Resumo:
The aim of this thesis was to identify the best grease removal technique with the application of low power of UV light to TiO2 coated grease filters. The treatment with various power series of ozone generating and ozone free lamps to normal grease filters and TiO2 coated grease filters were examined and the obtained results are compared to each other in this paper. The effect of ozone reaction was observed and compared with the effect of TiO2. The experiments were solely based on the photo oxidation and photo catalytic oxidation reactions. TiO2 is a green catalyst used in the photocatalytic reaction. Sunflower oil was used for grease production and tetracholoroethylene as a solvent. Grease samples were collected from the ventilation duct connected to the cooking hood system. Sample extraction was done in ultrasonic bath with the principle of sonication. The sample analysis was done by FTIR machine. The result determining the concentration of grease was the quantification of saturated C-H bonds in the chosen peak group of the spectrum. A very low power of UVC light functions perfectly with the Titanium dioxide. The experimental results have shown the combined treatment of titanium dioxide and UV light is an effective method in grease removal process. The photocatalytic reaction with titanium dioxide is better than photo oxidation reaction with ozone treatment. Photocatalytic reaction is environmentally friendly, energy efficient and economical.
Resumo:
The objective of the thesis is to study cerium oxide thin films grown by the atomic layer deposition (ALD) for soot removal. Cerium oxide is one of the most important heterogeneous catalysts and can be used in particulate filters and sensors in a diesel exhaust pipe. Its redox/oxidation properties are a key factor in soot oxidation. Thus, the cerium oxide coating can help to keep particulate filters and sensors clean permanently. The literature part of the thesis focuses on the soot removal, introducing the origin and structure of soot, reviewing emissions standards for diesel particulate matter, and presenting methods and catalysts for soot removal. In the experimental part the optimal ALD conditions for cerium oxide were found, the structural properties of cerium oxide thin films were analyzed, and the catalytic activity of the cerium oxide for soot oxidation was investigated. Studying ALD growth conditions of cerium oxide films and determining their critical thickness range are important to maximize the catalytic performance operating at comparatively low temperature. It was found that the cerium oxide film deposited at 300 °C with 2000 ALD cycles had the highest catalytic activity. Although the activity was still moderate and did not decrease the soot oxidation temperature enough for a real-life application. The cerium oxide thin film deposited at 300 °C has a different crystal structure, surface morphology and elemental composition with a higher Ce3+ concentration compared to the films deposited at lower temperatures. The different properties of the cerium oxide thin film deposited at 300 °C increase the catalytic activity most likely due to higher surface area and addition of the oxygen vacancies.
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Lecythidaceae is the family of the Brazil nut, and comprises about 300 species belonging to 17 genera with pantropical distributions. One hundred and twenty-two species belonging to nine genera are distributed throughout Brazil, demonstrating its greatest diversity in the Amazon rainforest where Lecythidaceae is also one of the most abundant families. It is usually difficult to collect fertile material from these trees because of their canopy heights, and species determinations using sterile material can be complex because of their morphological similarities. There have been relatively few studies of this family even though it is one of the most important groups in the Amazon region, and a detailed taxonomic treatment of the species of Lecythidaceae in the Tupé Sustainable Development Reserve was therefore the goal of the present work. Ten species were found, Allantoma lineata (Mart. ex O.Berg) Miers, Bertholletia excelsa Bonpl., Couratari tenuicarpa A.C.Sm., Lecythis poiteaui O. Berg; and six species of Eschweilera, the richest genus. The descriptions and identification keys of the species used 56 characters. The main reproductive characters useful for distinguishing the species were the pubescence of the inflorescence rachis, pedicel length and trichomes presence, floral symmetry, hood type, filament shape, stigma shape, fruit shape and size, and aril type. The most diagnostic vegetative characters were the type and color of the outer bark, inner bark color, midrib prominence, and petiole shape and pubescence.
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Demand for the use of energy systems, entailing high efficiency as well as availability to harness renewable energy sources, is a key issue in order to tackling the threat of global warming and saving natural resources. Organic Rankine cycle (ORC) technology has been identified as one of the most promising technologies in recovering low-grade heat sources and in harnessing renewable energy sources that cannot be efficiently utilized by means of more conventional power systems. The ORC is based on the working principle of Rankine process, but an organic working fluid is adopted in the cycle instead of steam. This thesis presents numerical and experimental results of the study on the design of small-scale ORCs. Two main applications were selected for the thesis: waste heat re- covery from small-scale diesel engines concentrating on the utilization of the exhaust gas heat and waste heat recovery in large industrial-scale engine power plants considering the utilization of both the high and low temperature heat sources. The main objective of this work was to identify suitable working fluid candidates and to study the process and turbine design methods that can be applied when power plants based on the use of non-conventional working fluids are considered. The computational work included the use of thermodynamic analysis methods and turbine design methods that were based on the use of highly accurate fluid properties. In addition, the design and loss mechanisms in supersonic ORC turbines were studied by means of computational fluid dynamics. The results indicated that the design of ORC is highly influenced by the selection of the working fluid and cycle operational conditions. The results for the turbine designs in- dicated that the working fluid selection should not be based only on the thermodynamic analysis, but requires also considerations on the turbine design. The turbines tend to be fast rotating, entailing small blade heights at the turbine rotor inlet and highly supersonic flow in the turbine flow passages, especially when power systems with low power outputs are designed. The results indicated that the ORC is a potential solution in utilizing waste heat streams both at high and low temperatures and both in micro and larger scale appli- cations.