Investigation of spontaneous combustion tendency of vegetable oils by the means of differential thermal analysis

The potential of vegetable oils to undergo violent thermal oxidation is long-known problem. The process of this oxidation is investigated by the means of differential thermal analysis. Polyurethane foam was saturated with Tung oil rich in unsaturated fatty acids at three different mass rations, and airfl ow at three different rates is introduces to the sample to ensure suffi cient volume of air for oxidation. The samples were thermally stressed both dynamically and isothermally. The results were compared to results of standard differential Mackey test

Ignition activation energy of materials based on polyamide 6

This contribution is aimed to compare the values of the ignition activation energies of two types of polyamide – Slovamid 6 FRB and Slovamid GF 50 LTS. Samples were isothermally stressed at fi ve different temperatures between 500 °C a 550 °C, while the time to initiation of the fl ame combustion was monitored. Subsequently from the measured times were compiled Arrhenius plots under which activation energy of ignition of both polymers were calculated. The values of activation energies were 106 kJ.mol-1 and 158.0 kJ.mol-1 for Slovamid 6 FRB 4 and Slovamid 6 GF 50 LTS

Využití technologií v díle Neuromancer od Williama Gibsona

With the technological transformation, human beings are also expected to change, transform and evolve. The advancements in bionics, computer and technological devices, cognitive and communication sciences, and robotics, have altered the perception of the human body and made it into more of a design object. Transhumanism stresses that future human beings would be capable of redesigning their bodies, in hope to transcend to a more evolved and higher being. This paper focuses on William Gibson's cyberpunk novel Neuromancer in the light of the concepts of transhumanism, cyberpunk, bionics, singularities, augmented reality, virtual reality, mind uploading, and artificial intelligence.Spolu s transformací technologií se i u lidských bytostí očekává, že se změní, transformují a vyvinou. Pokroky v bionice, počítačových a technologických zařízeních, kognitivních a komunikačních vědách a v robotice změnily pohled na lidské tělo. Vytvořily z něj tak designový objekt. Transhumanismus vyzdvihuje fakt, že budoucí lidské bytosti budou schopné upravovat svá těla v naději, že přesáhnou svou úroveň na vyvinutější a vyšší bytosti. Tato práce se zabývá cyberpunkovým románem Neuromancer od Williama Gibsona se zohledněním konceptů transhumanismu, cyberpunku, bioniky, singularity, rozšířené reality, virtuální reality, nahrávání myslí a umělé inteligence.Fakulta filozofick

Simple Methods for Determing the Inclination of Solid Materials to Self-Ignition

Práca sa zaoberá jednoduchými laboratórnymi metódami, ktoré boli vyvinuté na sledovanie sklonu tuhých látok k samovznieteniu. Konkrétne rieši problematiku tepelného samovznietenia pórovitých tuhých materiálov, prípadne pórovitých tuhých materiálov znečistených nenasýtenými olejmi. Tepelné samovznietenie je príčinou vzniku požiarov v mnohých priemyselných sušiarňach, skladoch, alebo v iných priemyselných odvetviach.This work deals with simple laboratory methods which have been developed to estimate the inclination to self-ignition of solids. Specifically deals with the thermal self-ignition of solid porous materials or porous solid materials contaminated with unsaturated oils. Thermal self-ignition is the cause of fires in many industrial ovens, storage facilities, or in other industrial segments

The use of safety calorimeter SEDEX for self-heating investigation of drying oils deposited on porous support

Evaluácia dynamických a kinetických parametrov procesu samozahrievania kvapalín alebo olejov so sklonom k samozahrievaniu je pomerne komplikovaná. Tieto kvapaliny musia byť nanesené na veľkom povrchu, aby bol zabezpečený dostatočný prísun vzdušného kyslíka. Na druhej strane je potrebné zabezpečiť podmienky, pri ktorých nedochádza k veľkým stratám tepla zo vzorky. Navyše pri overovaní reprodukovateľnosti meraní má príprava vzorky s homogénnymi vlastnosťami veľký vplyv na výsledky, preto sú vhodnejšie vzorky veľkých objemov. Veľkoobjemové vzorky nie sú vhodné na analýzu pomocou klasických metód termickej analýzy ako je napríklad DSC. Na rozdiel od DSC, je bezpečnostný kalorimeter SEDEX v mnohých ohľadoch veľmi flexibilný a umožňuje aj analýzu vzoriek väčších objemov.Evaluation of dynamic and kinetic parameters of the self-heating process of liquids or oils with propensity to self-heating is quite complicated. These liquids must be applied on a large surface area in order to ensure a sufficient supply of atmospheric oxygen. On the other hand, it is necessary to provide conditions under which there are only small heat losses from the sample. Moreover, to verify the reproducibility of the measurements, the sample preparation with homogeneous properties has great infl uence on the results, therefore, larger volumes of samples are preferred. Bulk samples are not suitable for analysis by classical methods of thermal analysis such as DSC. Unlike DSC, the safety Calorimeter SEDEX in is very flexible and allows the analysis of samples of larger volumes

Methods of investigation of tendency to spontaneous ignition of solid materials wetted with a liquid

If a solid material of large surface area is contaminated with a liquid with a propensity to low-temperature thermal oxidation (most often oil high in unsaturated fatty acids), under certain conditions it can self-ignite. To identify the tendency to self-ignition of substances, there have been developed a number of methods, such as differential Mackey test, or recommended the use of other classical methods of thermal analysis, which however are not suited for the analysis of samples of larger volume. DTA and ARC appear to be among the best methods of thermal analysis, for the evaluation of dynamic and kinetic parameters of the process of self-heating of such samples

Computer modeling of the smoke spread in enclosed space during fire

Podľa zvoleného požiarneho scenára sa sledovalo šírenie dymu v uzavretom priestore rodinného domu pomocou computational fluid dynamics modelu. Výsledkom požiarnej simulácie bolo aj sledovanie koncentrácie plynov oxidu uhličitého a oxidu uhoľnatého, vznikajúcich pri požiari sedacej súpravy, kde ako materiál bola použitá hlavne polyuretánová pena.According to the chosen fire scenario was monitored spread of smoke in enclosed space of the house by using computational fluid dynamics model. The result of a fire simulation was also monitoring of carbon dioxide and carbon monoxide concentrations, resulting from the fire of sofa, in which the main used material was polyurethane foam

Investigation of propensity to spontaneous combustion of vegetable oils deposited on an inert porous carrier

Minerálna vata používaná na zatepľovanie budov, ktorá bola žíhaná počas jednej hodiny pri teplote 600 °C bola následne posekaná a použitá ako porézny nosič pre tri vybrané rastlinné oleje. Na 3,5 g minerálnej vaty bol nanesený 1g rastlinného oleja v podobe centrálnej škvrny a následne bola vzorka vystavená termálnemu namáhaniu s dynamickým ohrevom v bezpečnostnom kalorimetri SEDEX. Po dynamickom ohreve bola čerstvá vzorka namáhaná izotermicky.Mineral wool used for the insulation of buildings, which has been annealed for one hour at 600 °C, was then shredded and used as a porous support for the three selected vegetable oils. One gram of vegetable oil was applied to 3.5 grams of mineral wool in the form of a central spot and then the sample was thermally stressed by the means of dynamic heating in the safety calorimeter SEDEX. After the dynamic heating, a fresh sample was isothermally stressed