Search

Start Over Coverage 121-129

3. Stress state analysis of sub-sized pre-cracked three-point-bend specimen

Creator:
Stratil, Luděk, Kozák, Vladislav, Hadraba, Hynek, and Dlouhý, Ivo
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
KLST, three-point bending, side grooving, Eurofer ‘97, and J-integral
Language:
English
Description:
The contribution deals with finite element analysis of stress state in sub-sized pre-cracked three-point bend specimen (KLST). A studied material was Eurofer ‘97 steel. The true stress-true strain curve was obtained from tensile test. The three-point-bend tests were carried out on pre-cracked plain and side-grooved specimens at ambient temperature. Performed tests were simulated using FEA software ABAQUS 6.10. The stress state in KLST specimen was compared with the stress state of pre-cracked Charpy and 1T SENB. The analysis confirmed the stress state of standard fracture toughness determination because loss of crack-tip and out-of-plane constraint. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. The effect of cellular organic matter produced by cyanobacteria Microcystis aeruginosa on water purification

Creator:
Pivokonský, Martin, Pivokonská, Lenka, Bäumeltová, Jitka, and Bubáková, Petra
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
AOM (Algal Organic Matter), COM (Cellular Organic Matter), destabilisation, aggregation, reaction conditions, water purification, organické látky produkované fytoplanktonem, buněčné organické látky, destabilizace, agregace, reakční podmínky, and úprava vody
Language:
Slovak
Description:
The aim of this paper is to investigate the influence of COM (Cellular Organic Matter) produced by Microcystis aeruginosa on the process of water purification by destabilisation and subsequent aggregation of the impurity particles. The research was carried out with a raw water into which COM was added. The removal efficiency of the most significant components of COM, i.e. polysaccharides and proteins, was investigated. It was found that the removal efficiency of polysaccharides and proteins was dependent on the reaction conditions (pH, type of destabilisation reagent and its dosage). The removal efficiency of COM was relatively low. It was about 46% and 41% using ferric sulphate and aluminium sulphate aggregation, respectively. In comparison to the other organic components of COM, mainly polysaccharides, the proteins are removed with a higher efficiency. The GPC analyses of the residual COM showed that the proteins of higher molecular weight were aggregated with a higher efficiency. and Cílem práce je opis vlivu buněčných organických látek (COM) produkovaných sinicí Microcystis aeruginosa na proces úpravy vody pomocí destabilizace a následné agregace znečišťujících příměsí. Výzkum byl uskutečňován se syntetickou surovou vodou, do které byly přidány COM získané laboratorní kultivací M. aeruginosa. V průběhu laboratorních testů byla sledována především účinnost odstranění dvou základních složek COM, tj. polysacharidů a proteinů. Bylo zjištěno, že tato účinnost závisí především na reakčních podmínkách (typu a dávce destabilizačního činidla a pH). Účinnost odstranění COM byla poměrně nízká, maximální dosažená účinnost byla 46% při destabilizaci pomocí síranu železitého a 41% při použití síranu hlinitého. Bylo zjištěno, že s vyšší účinností jsou odstraňovány proteiny, obzvláště pak proteiny s vyšší molekulovou hmotností.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public