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Start Over Coverage 208-213

2. Historie tokamaku ve světě a u nás

Creator:
Řípa, Milan
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Sacharov, Andrej Dmitrijevič, 1921-1989, Ústav fyziky plazmatu (Akademie věd ČR), fyzika plazmatu, řízená termojaderná syntéza, tokamaky, plasma physics, controlled thermonuclear fusion, tokamaks, 6, and 53
Language:
Czech
Description:
Počátkem roku uplynulo padesát let od zahájení provozu tokamaku T-1 - prvního zařízení s názvem tokamak. Stalo se tak v LIPAN, dnešním Kurčatovově ústavu pro atomovou energii v Moskvě. - V září tomu bude padesát let, kdy na II. mezinárodní konferenci o mírovém využití atomové energie v Ženevě padlo definitivně informační embargo ohledně výzkumu řízené termojaderné fúze. - V srpnu uplyne čtyřicet let, kdy na III. mezinárodní konferenci o fyzice plazmatu a řízené termojaderné syntéze v Novosibirsku vystoupil L. A. Arcimovič se skvělou zprávou. Na tokamaku T-3 v moskevském Ústavu pro atomovou energii I. V. Kurčatova dosáhli teploty plazmatu pět milionů stupňů a nepozorovali obávanou Bohmovu difuzi vedoucí ke značným tepelným ztrátám. - 10. srpna 1978 v Národní laboratoři pro fyziku plazmatu v Princetonu na tokamaku PLT (Princeton Large Torus) úspěšně použili dodatečný ohřev čtyřmi vysokoenergetickými svazky neutrálních atomů, každý o výkonu 0,9 MW a dosáhli rekordní teploty plazmatu 82 milionů stupňů. - 25. července 1983 - před dvaceti pěti roky - zapálil největší tokamak na světě - evropský JET - první plazma, čímž zahájil svoji tak úspěšnou kariéru., Milan Řípa., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Influence of water temperature on results of current meter calibration and measurement

Creator:
Mattas, Daniel and Ramešová, Libuše
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
current meter, measurement uncertainty, and water temperature influence
Language:
Slovak
Description:
On the basis of the results of calibration of current meters at water of varying temperatures, a hypothesis that water temperature influences measured water velocities was formulated. The analysis of our long-term data showed that the water temperature does have an influence on measured water velocity. This influence can be taken into account for practical purposes as a contribution to the uncertainty of measurements. The influence depends on the type of current meter propeller. This paper presents results obtained for the Ott C-2 current meter with propellers of the types 1, 2, 3, 5 and 6. Our analysis showed that the uncertainty is equal or less than 5% for measurements carried out in water with temperatures above 8°C. The differences between measured water velocities for water temperatures 5°C and 20°C reached maximum 6% (depending on the propeller) in a slowly flowing water (rotational frequency n = 1 s-1 ). For rotational velocity n ≥ 2 s-1 the differences between velocities measured at water temperatures 5 and 20°C were mostly under 3%. The less influenced propeller is of type 3 for which the uncertainty of measurement does not reach 5% even for water temperature 1ºC if the rotational frequency is bigger than 0.7 s-1 .
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Nákladovosť, produktivita a vplyvy tepelných spôsobov rezania na vlastnosti konštrukčnej ocele

Creator:
Harničárová, Marta, Valíček, Jan, and Zajac, Jozef
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
thermally interfered area, productivity, cost, tepelne ovplyvnená oblasť, produktivita, and nákladovosť
Language:
Czech
Description:
This work compares thermal cutting processes from the point of view of a thermal interference depth of the cut edge effective for construction steel EN S355J0 and deals with a cost and productivity of various cutting technologies. Results allow to estimate the technologies on the base of the mechanical changes in the cut edges, to determine their advantages and drawbacks and to look inside the technical/qualitative process characteristics. and Práca sa zaoberá vzájomným porovnaním tepelných spôsobov rezania materiálov z hľadiska ich vplyvu na dosiahnutú hĺbku tepelného ovplyvnenia hrany rezu u konštrukčnej oceli typu EN S355J0, nákladovosti a produktivity práce jednotlivých technológií rezania materiálov. Z výsledkov je možné porovnať tieto technológie z hľadiska zmeny ich mechanických vlastností na hrane rezu, určiť výhody, nevýhody daných technológií a oboznámiť sa s technicko-kvalitatívnymi charakteristikami procesov.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Photosystem 2 activity of Citrus volkameriana (L.) leaves as affected by Mn nutrition and irradiance

Creator:
Papadakis, I. E., Giannakoula, A., Antonopoulou, C. P., Moustakas, M., Avramaki, E., and Therios, I. N.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll fluorescence, deficiency, photoinhibition, photosystem 2, and toxicity
Language:
Multiple languages
Description:
Citrus volkameriana (L.) plants were grown for 43 d in nutrient solutions containing 0, 2, 14, 98, or 686 µM Mn (Mn0, Mn2, Mn14, Mn98, and Mn686, respectively). To adequately investigate the combined effects of Mn nutrition and irradiance on photosystem 2 (PS2) activity, irradiance response curves for electron transport rate (ETR), nonphotochemical quenching (qN), photochemical quenching (qP), and real photochemical efficiency of PS2 (ΦPS2) were recorded under 10 different irradiances (66, 96, 136, 226, 336, 536, 811, 1 211, 1 911, and 3 111 µmol m-2 s-1, I66 to I3111, respectively) generated with the PAM-2000 fluorometer. Leaf chlorophyll content was significantly lower under Mn excess (Mn686) compared to Mn0; its highest values were recorded in the treatments Mn2-Mn98. However, ETR and ΦPS2 values were significantly lower under Mn0 compared to the other Mn treatments, when plants were exposed to irradiances ≥96 µmol m-2 s-1. Furthermore, Mn0 plants had significantly higher values of qN and lower values of qP at irradiances ≤226 and ≥336 µmol m-2 s-1, respectively, than those grown under Mn2-Mn686. Irrespective of Mn treatment, the values of ΦPS2 and qN decreased, while those of qP increased progressively by increasing irradiance from I136 to I3111. Finally, Mn2-Mn98 plants were less sensitive to photoinhibition of photosynthesis (≥811 µmol m-2 s-1) than the Mn686 (≥536 µmol m-2 s-1) and Mn0 (≥336 µmol m-2 s-1) ones. and I. E. Papadakis ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public