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1892. Květy z českých luhů: výbor básní pro mládež, jejž uspořádali F.V. Krch a J.V. Novák
- Creator:
- František Vladimír Krch and Jan Václav Novák
- Publisher:
- Nakaladtelství I.L. Kober
- Format:
- print, text, regular print, and 153 s. ; 17 cm
- Type:
- model:monograph and TEXT
- Subject:
- Česká poezie, Literatura pro děti a mládež (beletrie), 821.162.3-1, 821-93, (082.21), (0:82-1), 25, and 26
- Language:
- Czech and Slovak
- Description:
- II, Básně lyrické, and Text český a slovenský
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1893. Laboratorní infiltračně výtokový experiment monitorovaný metodou magnetické rezonance
- Creator:
- Sněhota, Michal and Císlerová, Milena
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- preferential flow, heterogeneous soil, infiltration, magnetic resonance, magnetic resonance imaging, computer tomography, preferenční proudění, heterogenní půda, infiltrace, magnetická rezonance, snímkování, and počítačová tomografie
- Language:
- Slovak
- Description:
- Infiltration-outflow experiments were performed on undisturbed soil samples of coarse sandy loam simultaneously with the imaging of flow process by means of magnetic resonance (MR) imaging. The flow in soil under study is highly preferential and exhibits time instability of soil hydraulic properties. For the transient part of infiltration runs, fast 2D imaging was used. For the steady state flow and for the equilibrium state after drainage, horizontal 2D imaging and mapping of longitudinal relaxation (T1) was performed. To obtain the information about internal soil structure all samples were imaged by the computer tomography (CT). The results of all the measurements represent a unique data set. For each sample it contains a record of cumulative infiltration and outflow, hydraulic pressure heads and the simultaneous MR visualization of each particular experiment. Suction pressure heads show a good agreement with the propagation of the wetting front in the sample as displayed by the MR at the very beginning of the each infiltration run. Presented data are the result of first experiment, where MR imaging of infiltration into undisturbed soil samples was combined with concurrent monitoring of suction pressure heads. The next step is to use the gained data for modeling of the infiltration in heterogeneous soil. and Uskutečnili jsme infiltračně výtokový experiment na neporušených vzorcích hlinitopísčité půdy za souběžného snímkování metodou magnetické rezonance (MR). Zkoumaná půda vykazuje výrazné preferenční proudění a časovou závislost hydraulických charakteristik. Pro transientní fáze experimentů jsme použili rychlého vertikálního 2D snímkování. Při ustáleném proudění a při rovnovážném stavu byly pořízeny horizontální 2D snímky a bylo provedeno mapování podélné relaxivity (T1). Pro zjištění vnitřní struktury pevné fáze byly všechny vzorky v suchém stavu snímkovány počítačovou tomografií (CT). Výsledkem experimentu je komplexní soubor dat, který kromě snímků MR obsahuje záznam kumulativní infiltrace výtoku a tlakových výšek. Možnosti metody MR jsou demonstrovány na příkladu porovnání sledu 2D snímků MR s měřenými sacími tlakovými výškami během transientní části infiltrace, kde obě měření shodně zaznamenaly postup čela zvlhčení. Prezentovaná data jsou výsledkem prvního snímkování infiltrace do neporušených vzorků půdy pomocí MR v kombinaci se souběžným měřením sacích tlaků. Dalším krokem bude použití takového souboru dat jako podkladu pro modelování procesu infiltrace do půdy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1894. Laboratory studies on bedload transport under unsteady flow conditions
- Creator:
- Mrokowska, Magdalena M., Rowiński, Paweł M., Książek, Leszek, Strużyński, Andrzej, Maciej, and Radecki-Pawlik, Artur
- Type:
- article, model:article, and TEXT
- Subject:
- bedload, bed shear stress, dimensional analysis, hysteresis, stream power, and unsteady flow
- Language:
- Slovak
- Description:
- Two sets of triangular hydrographs were generated in a 12-m-long laboratory flume for two sets of initial bed conditions: intact and water-worked gravel bed. Flowrate ranging from 0.0013 m3 s–1 to 0.0456 m3 s–1, water level ranging from 0.02 m to 0.11 m, and cumulative mass of transported sediment ranging from 4.5 kg to 14.2 kg were measured. Then, bedload transport rate, water surface slope, bed shear stress, and stream power were evaluated. The results indicated the impact of initial bed conditions and flow unsteadiness on bedload transport rate and total sediment yield. Difference in ratio between the amount of supplied sediment and total sediment yield for tests with different initial conditions was observed. Bedload rate, bed shear stress, and stream power demonstrated clock-wise hysteretic relation with flowrate. The study revealed practical aspects of experimental design, performance, and data analysis. Water surface slope evaluation based on spatial water depth data was discussed. It was shown that for certain conditions stream power was more adequate for the analysis of sediment transport dynamics than the bed shear stress. The relations between bedload transport dynamics, and flow and sediment parameters obtained by dimensional and multiple regression analysis were presented.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1895. Laboratory study on the interaction between herbicide MCPA and two different soils
- Creator:
- Hiller, Edgar, Dubovský, Dávid, Bartaľ, Mikuláš, Zemanová, Lenka, and Khun, Miloslav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- degradation, sorption, desorption, MCPA, soil, degradácia, sorpcia, desorpcia, and pôda
- Language:
- Slovak
- Description:
- Acidic herbicide MCPA (4-chloro-2-methylphenoxyacetic acid) is applied to post-emergence control of annual and perennial broad-leaved weeds, mostly in cereals. This study was undertaken with two soils of different properties sampled from two soil horizons to determine the extent of degradation, sorption and desorption of MCPA. These processes are the most important to evaluate the fate of the herbicide in soil and its potential to leach from soil into groundwater. Two soils were used: a calcareous, sandy-loam soil with organic carbon content of 2.486 % (Pararendzina) taken from surface A horizon (the A topsoil) and a calcareous, loamy-sand soil with organic C content of 0.600 % (Fluvisol) sampled from subsurface C horizon (the C subsoil). The extent of degradation, sorption and desorption of MCPA were measured in laboratory batch experiments. Degradation followed first-order kinetics, with the MCPA half-lives of 11 and 24 d for the A topsoil and C subsoil, respectively. Soil organic carbon influenced MCPA degradation. Sorption followed a Freundlich isotherm equation and linear isotherm equation, as well. The distribution coefficient KD was higher in the A topsoil (0.387 l kg-1) than in the C subsoil (0.165 l kg-1), consistent with the higher organic C content of the A soil. The results indicate that MCPA is potentially mobile and might pose a threat to future groundwater quality due to its low sorption, relatively high water solubility and slow degradation in the C subsoil. and MCPA, slabokyslý herbicíd, sa používa postemergentne na ničenie jednoročných a trvalých širokolistých burín, najmä v obilninách. Cieľom tejto práce bolo štúdium degradácie, sorpcie a desorpcie MCPA v dvoch rozdielnych pôdach odobratých z odlišnej hĺbky. Tieto procesy v najväčšej miere ovplyvňujú celkové správanie MCPA v pôdach a determinujú jeho migračný potenciál. Použité pôdy boli: karbonátová, piesčito-hlinitá pôda s obsahom organického uhlíka 2,486 % (pararendzina) odobratá z vrchného A horizontu (pôda A) a karbonátová, hlinito-piesčitá pôda s obsahom organického uhlíka 0,600 % (Fluvizem), so znakmi oglejenia odobratá z C horizontu v hĺbke 2 m (pôda C). Všetky sledované procesy boli realizované v nádobkových experimentoch. Rozklad MCPA vyhovoval rýchlostnej rovnici reakcie prvého poriadku. Rozklad MCPA bol rýchlejší v pôde A so zisteným polčasom rozkladu 11 dní ako v pôde C s polčasom rozkladu 24 dní. Rozklad MCPA súvisel s odlišným obsahom organického uhlíka v týchto dvoch vzorkách pôd. Získané sorpčné izotermy MCPA vyhovovali rovniciam Freundlichovej a lineárnej sorpčnej izotermy. Rozdeľovací koeficient KD MCPA bol vyšší pre pôdu A (0,387 l kg-1) ako pre pôdu C (0,165 l kg-1). Vyššia sorpčná kapacita pôdy A ako pôdy C sa zhodovala s vyšším obsahom organického uhlíka v pôde A. Výsledky tejto práce naznačujú, že MCPA je potenciálne mobilný herbicíd a môže predstavovať veľké riziko pre kvalitu podzemných vôd v dôsledku jeho málo účinnej sorpcie, pomerne vysokej rozpustnosti vo vode a zvýšenej perzistencii v hlbších častiach pôdneho profilu.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1896. Laboratory testing of granular kinetic theory for intense bed load transport
- Creator:
- Matoušek, Václav and Zrostlík, Štěpán
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- granular flow, sheet flow, sediment transport, grain collision, and tilting flume experiment
- Language:
- Slovak
- Description:
- Collisional interactions in a sheared granular body are typical for intense bed load transport and they significantly affect behavior of flow carrying bed load grains. Collisional mechanisms are poorly understood and modelling approaches seldom accurately describe reality. One of the used approaches is the kinetic theory of granular flows. It offers constitutive relations for local shear-induced collision-based granular quantities – normal stress, shear stress and fluctuation energy – and relates them with local grain concentration and velocity. Depth distributions of the local granular quantities produced by these constitutive relations have not been sufficiently verified by experiment for the condition of intense bed load transport in open channels and pressurized pipes. In this paper, results from a tilting-flume facility including measured velocity distribution and deduced concentration distribution (approximated as linear profiles) are used to calculate distributions of the collision-based quantities by the constitutive relations and hence to test the ability of the kinetic-theory constitutive relations to predict conditions observed in these collision-dominated flows. This test indicates that the constitutive relations can be successfully applied to model the local collisional transport of solids at positions where the local concentration is not lower than approximately 0.18 and not higher than approximately 0.47.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1897. Ladislav Hagara. Ottova encyklopédia húb - recenze
- Creator:
- Gavorník, Peter
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, review, recenze, and TEXT
- Language:
- Czech and Slovak
- Description:
- Peter Gavorník
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1898. Lanžhot
- Publisher:
- Vojenský zeměpisný ústav
- Format:
- map and 1 mapa : barevná ; 39 x 51 cm na listu 48 x 63 cm
- Type:
- model:map, cartographic, and IMAGE
- Subject:
- udc:913(4), Konspekt:7, udc:912, udc:913(437.322), udc:912.43, udc:(084.3), Konspekt:Geografie Evropy, reálie, cestování, Konspekt:Mapy. Atlasy. Glóby, and czenas:Lanžhot (Česko)
- Language:
- Czech, Slovak, and German
- Description:
- 4558, Legenda, Edice dle kladu listů, and (Language) Místní názvy česky, slovensky a německy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1899. Laténske a rímske relikty v slovansko-avarských hroboch na Slovensku /
- Creator:
- Kraskovská, Ľudmila,
- Type:
- text, studie, and soupisy
- Subject:
- Archeologie, archeologie, nálezy, hroby slovanské, kultura laténská, doba římská, and Slovensko v pravěku
- Language:
- Slovak
- Description:
- Die latènezeitlichen und römischen Relikte in der slawisch-awarischen Gräbern in der Slowakei.
- Rights:
- unknown
1900. Lateral momentum transfer effects in the modeling of unsteady flows in compound channels
- Creator:
- Abida, Habib and Ellouze, Manel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- compound channel, main channel, flood plain, flood routing, lateral momentum transfer, unsteady flow, zložený profil (koryta), hlavné koryto, inundácia, prenos priečnej hybnosti, and neustálené prúdenie
- Language:
- Slovak
- Description:
- The impact of lateral momentum transfer (LMT) on channel conveyance is examined through applications of a new mathematical model for routing unsteady flows in compound channels. The model accounts for LMT through three parameters that relate: (i) 'actual' to 'isolated' sub-section discharge, (ii) main channel to flood plain lengths between stations, and (iii) flood plain to main channel depths. The model was applied to route a series of flood events in a hypothetical compound channel consisting of a deep smooth main channel between two wide and rough flood plain zones. The routing exercise was repeated with and without LMT in the analysis. Three empirical methods to account for LMT were investigated by comparing their corresponding simulated stage and discharge hydrographs. In general, LMT was found to have little impact on simulated stage hydrographs, however, for the case of small flood plain flows, LMT was responsible for some attenuation in the discharge hydrographs. and Príspevok skúma vplyv priečnej zložky hybnosti na prúdenie použitím nového matematického modelu neustáleného pohybu v zložených otvorených kanáloch. Použitý model zohľadňuje efekt priečnej hybnosti prostredníctvom troch parametrov, daných pomerom: (i) aktuálneho a ''oddeleného'' prietoku v danom úseku koryta, (ii) dĺžkou inundácie a dĺžkou úseku a (iii) plochy inundácie a plochy hlavného koryta v úseku. Model bol aplikovaný na výpočet niekoľkých povodňových udalostí v hypotetickom zloženom kanále s hladkým hlavným (hlbokým) korytom s obojstrannou drsnou inundáciou. Výpočty sa realizovali s akceptovaním a s vynechaním efektu priečnej hybnosti. Pri tom boli skúmané tri empirické metódy výpočtu priečnej hybnosti porovnávaním výsledkov na prietokových a hladinových hydrografoch. Výsledky preukázali, že účinok priečnej hybnosti sa ukázal len pri prietokoch, pri čom ich vplyv na priebeh hladín bol nevýznamný. Okrem toho výpočty pre korytá s malou inundáciou ukázali, že priečna hybnosť spôsobuje zoslabenie prietokov.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public