Tyrimo tikslas – nustatyti stabdžių skysčio eksploatacinių rodiklių kitimą automobiliuose su senu ir automobiliuose su naujai užpiltu stabdžių skysčiu, atsižvelgiant į Lietuvos sąlygas ir automobilių eksploatavimą. Tyrimai atlikti su keturiais automobiliais, dviejuose automobiliuose skystis buvo nežinomas, o likusiuose pakeistas nauju. Atsižvelgiant į eksploatacijos ir oro sąlygas, bei automobilių amžių, gavome tokius teiginius.Aplinkos temperatūrai nukritus žemiau 0 °C, vandens kiekis stabdžių skystyje didėja, o skysčio virimo temperatūra mažėja.Nustatyta, didesnis vandens kiekis susikaupė tokioje automobilio sistemoje, kuri buvo eksploatuojama mažiau.Galima teigti, kad automobilis, kuris yra tankiau stabdomas, dėl įkaitusios sistemos, stabdžių skystyje susidaręs vanduo palaipsniui garuoja.Galima teigti, kad oro temperatūrai esant apie + 20 °C, vandens kiekis stabdžių sistemose pradeda garuoti, arba išlieka nekitęs ir būna mažesnis.Remiantis surinktais duomenimis ne visus pokyčius galime paremti tiksliomis išvadomis, todėl būtų tikslinga tęsti matavimus įvertinant faktorius. / The purpose - to set the brake fluid dynamics performance indicators with the old cars, and cars with the newly brewed brake fluid, according to Lithuanian conditions and vehicle. Investigations were carried out with four cars, two cars liquid was unknown, and the remaining replacement. Given the operational and weather conditions, and car's age, received such claims. Ambient temperature falls below 0°C, water brake fluid increases and the boiling point of the liquid drop. Found greater amount of water accumulated in a car system, which has been operated less. It can be said that the car, which is densely stopped for hot systems, brake fluid resulting from water gradually evaporates. It can be argued that the air temperature of +20 °C, water starts to evaporate, brake systems, and remains unchanged is lower. Based on data collected at all the changes we can support precise conclusions, it would be appropriate to continue the measurements evaluating factors.

El premio Ig-Nobel de Química de este año 2015 fue entregado al profesor Tom Yuan y su equipo de colaboradores por crear una receta para “deshervir un huevo” de forma sencilla. Aunque no lo aparente, este trabajo es de vital importancia, pues ofrece la posibilidad de regresar proteínas desnaturalizadas y agregadas a su estado natural, lo que podría beneficiar a la industria actual evitando la pérdida de miles de millones de dólares. / Professor Tom Yuan and his team were awarded the Ig-Nobel Prize in Chemistry 2015 for creating a recipe to “unboil” an egg. Although it may seem unimportant, this work has crucial importance, as it offers the possibility of refolding denatured proteins and getting them back to its natural state. This research might have an impact on industry, as it could prevent the loss of billions of dollars.

A análise microbiológica atua como ferramenta fundamental para a obtenção de dados sobre a qualidade, sanidade, higiene e segurança na produção de alimentos; desta forma, tem sido adotada na indústria alimentícia para o controle de qualidade. Por sua composição completa e balanceada, o leite é um substrato ideal para o desenvolvimento de diversos grupos de microrganismos. Com o objetivo de pesquisar bactérias da espécie Bacillus cereus em amostras de leite fluido, bem como a capacidade de germinação de esporos e a multiplicação dessa bactéria após processo de fervura, com manutenção das amostras à temperatura ambiente e à temperatura de refrigeração por períodos de 1, 2, 4, 6, 8, 10 e 12 horas, foram analisadas 75 amostras de leite, conforme as metodologias recomendadas por Silva et al. (2007). Destas, 46 amostras (61,3%) mostraram-se com algum grau de contaminação pela bactéria antes de serem submetidas à fervura. Por sua vez, as amostras mantidas à temperatura ambiente após a fervura, tiveram suas contagens bacterianas, principalmente a partir da 8a hora, superiores à contagem inicial, inclusive atingindo níveis capazes de desencadear uma toxinfecção alimentar, demonstrando a ocorrência da germinação dos esporos e a multiplicação das células vegetativas. Por outro lado, alíquotas dessas mesmas amostras mantidas sob refrigeração (7ºC) não atingiram populações preocupantes, enfatizando, desse modo, a importância da necessidade da refrigeração do leite após a fervura. / The microbiological analysis acts as basic tool for the attainment of data on the quality, health, hygiene and security in the food production, in such a way, she has been adopted in the nourishing industry for the quality control. For its complete and balanced composition, milk is an ideal substratum for the development of diverse groups of microorganisms. With the objective to search cereus bacteria of the Bacillus species in fluid milk samples, as well as the capacity of germination of spores and the multiplication of this bacterium after boil process, with maintenance of the samples to the ambient temperature and the temperature of refrigeration for periods of 1, 2, 4, 6, 8, 10 and 12 hours, 75 milk samples had been analyzed, as the methodologies recommended for Silva et al. (2007). Of these, 46 samples (61.3%) had revealed with some degree of contamination for the bacterium before being submitted to the boil. In turn, the samples kept to the ambient temperature after the boil, had its bacterial countings, mainly from 8a hour, superiors to the initial counting, also reaching levels capable to unchain an alimentary toxinfection, demonstrating to the occurrence of the germination of the spores and the multiplication of the vegetative cells. On the other hand, aliquot of these same samples kept under refrigeration (7ºC) had not reached preoccupying populations, emphasizing, in this manner, the importance of the necessity of the refrigeration of milk after the boil.

No description available.

<p>The slag metal emulsion may play a significant role in the global furnace decarburization kinetics in oxygen steelmaking. In recent years, the important interaction between droplet generation rate, droplet residence time in slag and droplet decarburization rate has become more evident in the literature. The decarburization kinetics of Fe-C-S droplets in CaO-SiO2-MgO-FeO slags were investigated for highercarbon droplets (approximately 4.2 % C). The effect of slag FeO, droplet mass and Sulphur content on decarburization rate were evaluated. The limit between external and internal nucleation of CO gas was investigated. A model was developed for prediction oftime to the onset of carbon boil.</p> / Master of Science (MSc)

This work presents the use of numerical modeling and simulation for the analysis of transport phenomena in engineering systems including zero boil-off (ZBO) cryogenic storage tanks for liquid hydrogen, refrigerated warehouses, and human-occupied air-conditioned spaces. Seven problems of medium large spaces in these fields are presented. Numerical models were developed and used for the simulation of fluid flow and heat and mass transfer for these problems. Governing equations representing the conservation of mass, momentum, and energy were solved numerically resulting in the solution of velocity, pressure, temperature, and species concentration(s). Numerical solutions were presented as 2-D and 3-D plots that provide more insightful understanding of the relevant transport phenomena. Parametric studies on geometric dimensions and/or boundary conditions were carried out. Four designs of ZBO cryogenic liquid hydrogen storage tank were studied for their thermal performance under heat leak from the surroundings. Steady state analyses show that higher flow rate of forced fluid flow yields lower maximum fluid temperature. 3-D simulation provides the visualization of the complex structures of the 3-D distributions of the fluid velocity and temperature. Transient analysis results in the patterns of fluid velocity and temperature for various stages of a proposed cooling cycle and the prediction of its effective operating term. A typical refrigerated warehouse with a set of ceiling type cooling units were modeled and simulated with both 2-D and 3-D models. It was found that if the cooling units are closer to the stacks of stored packages, lower and more uniform temperature distribution can be achieved. The enhancement of thermal comfort in an air-conditioned residential room by using a ceiling fan was studied and quantified to show that thermal comfort at higher temperature can be improved with the use of ceiling fan. A 3-D model was used for an analysis of thermal comfort and contaminant removal in a hospital operating room. It was found that if the wall supply grilles are closer to the center, the system has better performance in both contaminant removal and thermal comfort. A practical guideline for using CFD modeling in indoor spaces with an effective meshing approach is also proposed.

The effectiveness of Boil Water Advisories (BWAs) as a public health risk management tool is increasingly being questioned. Newfoundland and Labrador's zero-risk policy for issuing BWAs on public drinking water systems has resulted in over 210 active BWAs annually, the majority classified as long-term BWAs. BWAs are more likely to occur on small systems, in communities with low economic capacity, and in communities without a certified operator. No relationship was found relating confirmed cases of water-related illness to BWAs. Quantifiable health risk associated with BWAs was evaluated using Quantitative Microbial Risk Assessment (QMRA). Data on source water pathogen concentrations and epidemiological data was used to evaluate and calibrate the QMRA Model. The study demonstrated the application of QMRA in determining whether health risk warranted issuing a BWA. Eleven recommendations were made on how the province could adopt QMRA in establishing an alternative drinking water risk management and advisory framework.

Shape memory alloys (SMAs) can recover large strains (e.g., up to 8%) by undergoing a temperature-induced phase transformation. This strain recovery can occur against large forces, resulting in their use as actuators. The SMA elements in such actuators integrate both sensory and actuation functions. This is possible because SMAs can inherently sense a change in temperature and actuate by undergoing a shape change, associated with the temperature-induced phase transformation. The objective of this work is to develop an SMA based cryogenic thermal conduction switch for operation between dewars of liquid methane and liquid oxygen in a common bulk head arrangement for NASA. The design of the thermal conduction switch is based on a biased, two-way SMA actuator and utilizes a commercially available NiTi alloy as the SMA element to demonstrate the feasibility of this concept. This work describes the design from concept to implementation, addressing methodologies and issues encountered, including: a finite element based thermal analysis, various thermo-mechanical processes carried out on the NiTi SMA elements, and fabrication and testing of a prototype switch. Furthermore, recommendations for improvements and extension to NASA's requirements are presented. Such a switch has potential application in variable thermal sinks to other cryogenic tanks for liquefaction, densification, and zero boil-off systems for advanced spaceport applications. The SMA thermal conduction switch offers the following advantages over the currently used gas gap and liquid gap thermal switches in the cryogenic range: (i) integrates both sensor and actuator elements thereby reducing the overall complexity, (ii) exhibits superior thermal isolation in the open state, and (iii) possesses high heat transfer ratios between the open and closed states. This work was supported by a grant from NASA Kennedy Space Center (NAG10-323) with William U. Notardonato as Technical Officer.

As alternative fuels are becoming more common, technologies need to adjust to them. Natural gas is one of the alternative fuels that has grown during the latest years in the transport sector. Natural gas consists of around 97 % methane and is the cleanest fossil fuel. The use of natural gas can make it easier to transition to biogas as it has equivalent properties. Today Scania CV AB's trucks fuelled by natural gas are using auxiliary cabin heaters driven by diesel. This means that the natural gas trucks have two fuels on-board the truck. The goal of this project is to find a concept to eliminate the diesel fuel and replace it with an auxiliary cabin heater driven by another energy source. It will improve the heating solution and make it superior from an environmental perspective. The result of the project lead to a short-term solution with an auxiliary heater fuelled by natural gas. A long-term solution is to have a cooperation with a manufacturer to develop a better natural gas auxiliary heater that fulfils more of the requirements in the technical specification. An experiment plan is devised to test parameters out of reach of the project.