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2332. Ars Montana. Umělecký a kulturní transfer v otevřeném prostoru česko-saského Krušnohoří na prahu raného novověku, edd. Michaela Hrubá - Michaela Ottová - Jan Royt

Creator:
František Šmahel
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
medievalistika, medievalistics, ikonografie, iconography, dějiny hornictví, history of mining, hagiografie, hagiography, konfesionalizace, confessionalisation, novověk, modern history, Krušné hory (Česko a Německo : oblast), Krušné hory Mountains Region (Czechia and Germany), 8, and 930
Language:
Czech
Description:
[autor anotace] František Šmahel.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2335. Arsenic and zinc in impoundment materials and related stream sediments from a polluted area in Eastern Slovakia: distribution, mobility, and water quality

Creator:
Jankulár, Michal, Hiller, Edgar, Jurkovič, Ľubomír, Veselská, Veronika, and Majzlan, Juraj
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
arsenic, zinc, impoundment, mobility, stream sediment, bioavailability, Slovakia, arzén, zinok, odkalisko, pohyblivosť, riečny sediment, bioprístupnosť, and Slovensko
Language:
Slovak
Description:
The impoundment located near the village of Poša in eastern Slovakia is a significant source of arsenic. Waters penetrating the impoundment become enriched in As and other potentially toxic elements. As a consequence, the Kyjov brook and the Ondava River have been extensively polluted by arsenic. Although, zinc is of minor environmental significance regarding pollution in the area, it was also monitored to compare its behaviour with that of arsenic. The mobility and solid-state distribution of As and Zn in the impoundment materials and stream sediments have been investigated using a five-step sequential extraction procedure. Moreover, to investigate the bioavailability of As and Zn, two native plant species (Typha latifolia and Phragmites australis) growing at the site were collected and analyzed. The As concentrations in representative sediment and water samples ranged from 36.28 to 3208.35 mg kg-1 and from 4.05 to 612.8 μg l-1, respectively, both being many times above the background levels. The Zn concentrations of environmental importance were found to be high only in the impoundment materials (up to 3390 mg kg-1). Although a part of As was present in a readily soluble form (6.62%), the majority of As was mainly associated with Fe/Mn oxides (37.30%) and residual phases (51%). Similarly, the most dominant fractions for zinc distribution were Fe/Mn oxides (38.5%), residual (34%) and exchangeable (18%). Combined results of the sequential extraction tests as well as chemical and mineralogical analysis indicated that As mobilisation potential from the sediments is likely controlled by Fe/Mn oxyhydroxide mineral phases. Plants growing in the impoundment had As concentrations 10 to 100 times higher than the same plants growing in a relatively nonpolluted area, indicating an enhanced bioavailability of arsenic in the area with high total As contents in the impoundment materials. and Odkalisko, ktoré sa nachádza pri obci Poša (východné Slovensko), je významným zdrojom arzénu. Vody presakujúce cez materiál uložený v odkalisku sa tak obohacujú o As a ďalšie potenciálne toxické prvky. Dôsledkom je výrazné znečistenie toku Kyjov a rieky Ondava arzénom. Aj keď v tejto oblasti zinok nepredstavuje až tak veľký environmentálny problém, je zahrnutý v tejto štúdii s cieľom porovnať správanie sa týchto dvoch potenciálne toxických prvkov. Na štúdium pohyblivosti a distribúcie As a Zn v materiáloch odkaliska a v riečnych sedimentoch sa použila päťkroková sekvenčná extrakcia. Okrem toho sme skúmali bioprístupnosť As a Zn v dvoch typoch rastlín (Typha latifolia a Phragmites australis), ktoré prednostne rastú na odkalisku. Koncentrácie As v odobratých vzorkách sedimentov boli v intervale od 36,28 do 3208,35 mg kg-1 a v povrchových vodách od 4,05 do 612,8 μg l-1. Tieto koncentrácie sú oveľa vyššie ako pozaďové hodnoty pre danú oblasť. Bolo zistené, že koncentrácie Zn významné z hľadiska znečistenia sú vysoké len v odkaliskových materiáloch (až 3390 mg kg-1). Aj keď určitý podiel As v sedimentoch bol prítomný v ľahko rozpustnej forme (6,62 %), väčšina As bola viazaná na oxidy Fe a Mn (37,30 %) a reziduálne fázy (51 %). Podobné to bolo pri Zn, pričom najdôležitejšie pre jeho distribúciu boli oxidy Fe a Mn (38,5 %), reziduálne fázy (34 %) a vymeniteľné pozície (18 %). Kombinované výsledky sekvenčných extrakcií ako aj chemickej a mineralogickej analýzy ukázali, že mobilizácia As zo sedimentov úzko súvisí s prítomnými minerálmi zo skupiny oxyhydroxidov Fe a Mn. Rastliny vyskytujúce sa na odkalisku obsahovali 10- až 100-násobne vyššie koncentrácie As ako tie isté rastliny odobraté z relatívne neznečistenej oblasti. Táto skutočnosť poukazuje na zvýšenú bioprístupnosť arzénu na skúmanom odkalisku, ktoré je typické vysokými obsahmi celkového As v uložených materiáloch.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2336. Arsenic mobility in stream sediments and impoundment material as evaluated by column and batch experiments

Creator:
Hiller, Edgar, Veselská, Veronika, and Majzlan, Juraj
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
arsenic, release, migration, stream sediment, impoundment, contamination, arzén, uvoľňovanie, migrácia, riečny sediment, odkalisko, and znečistenie
Language:
Slovak
Description:
Arsenic release and its kinetic in severely contaminated stream sediments of the Kyjov brook and impoundment material (eastern Slovakia) using column and batch experiments was studied. The results of the column experiments showed that As release from the solid samples by water was likely controlled by Fe and Mn oxyhydroxides and pH of the sediments and leachates. It was also observed that extraction time was an important factor influencing the As release. The empirical correlations between the rate constants of As release and oxalate-extractable Fe content or total Mn content imply that diffusion in hydrated micropores of amorphous Fe and Mn oxides might be the rate-limiting mechanism of the As release. Although the fractions of As released in column experiments were generally less than 10 % of its total contents, these low fractions represented high absolute amounts of readily available and water-soluble As with a mean value of 83 mg kg-1. This amount of readily available As is approximately 4-times higher than the guideline value for As according to DEFRA UK, based upon ''bioavailable'' concentration, indicating high As availability for plants and living organisms in the studied region. and V štúdii bolo sledované uvoľňovanie arzénu a jeho rýchlosť vo výrazne kontaminovaných riečnych sedimentoch toku Kyjov na východnom Slovensku a materiáli odkaliska použitím kolónových a nádobkových experimentov. Výsledky kolónových experimentov naznačujú, že pravdepodobne najväčší vplyv na uvoľňovanie As vodou majú oxyhydroxidy Fe a Mn a pH výluhov a použitých sedimetov. Ukázalo sa, že aj čas trvania kontaktu kontaminovaných vzoriek s roztokom je dôležitý faktor uvoľňovania As. Nájdené korelácie medzi rýchlostnými konštantami uvoľňovania As a extrahovateľnými obsahmi Fe šťavelanom amónnym ako aj celkovými obsahmi Mn by mohli poukazovať na fakt, že difúzia v hydratovaných mikropóroch amorfných oxyhydroxidov Fe a Mn je hlavný mechanizmus limitujúci rýchlosť uvoľňovania As. Hoci frakcie uvoľneného As v kolónových experimentoch boli celkovo nižšie ako 10 % z jeho totálnych obsahov v skúmaných vzorkách, tieto nízke frakcie predstavujú vysoké obsahy ľahko dostupného a vo vode rozpustného As s priemernou hodnotou 83 mg kg-1. Uvedený obsah ľahko dostupného As je približne 4-krát vyšší ako smernicová hodnota podľa DEFRA UK založená na ''biodostupnej'' koncentrácii As. Toto porovnanie poukazuje na potenciálne vysokú dostupnosť As pre rastliny a živé organizmy v študovanej oblasti
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2337. Artefacts in gravity field modelling

Creator:
Klokočník, Jaroslav, Kostelecký, Jan, Bezděk, Aleš, and Kletetschka, Gunther
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
geologie, topografie, geology, topography, Artefacts: graining, aliasing, along-track stripes, gravity aspects, gravity field models, topography models, 7, and 551
Language:
English
Description:
Artefacts in applications of the global gravity field and topographic models based on satellite and terrestrial data of diverse kinds are studied. Various types of artefacts are presented and analysed with the aim to understand how the artefacts originated, how to reduce them (if feasible) and to avoid misinterpretations in geoscience. We work with the gravity aspects (gravity anomalies, the Marussi tensor of the second derivatives of disturbing potential, gravity invariants and their specific ratio, strike angles, and virtual deformations), and with surface or bedrock topography. Examples for the Earth, the Moon, and Mars are presented., Jaroslav Klokočník, Jan Kostelecký, Aleš Bezděk and Gunther Kleteschka., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2338. Artefacts, non-particulars and model particulars

Creator:
Thein, Karel
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
P.F. Strawson, non-particulars, model particulars, artefacts, and persons
Language:
Slovak
Description:
The paper comments and elaborates upon five pages of P. F. Strawson’s Individuals (1959, 230 - 234), together with his ‘Entity and Identity’ and ''Universals''. The focus is on Strawson’s understanding of individual non-particulars as types or universals, and on his contention that the most obvious non-particular entities (''well-entrenched non-particulars'') are the broadly conceived artefacts including the works of art. The narrow focus is on the implications of Strawson’s suggestion that ‘an appropriate model for non-particulars of these kinds is that of a model particular - a kind of prototype, or ideal example, itself particular, which serves as a rule or standard for the production of others’ (1959, 233). The paper analyzes the relation between Strawson’s position and the issue of artefacts and their (largely missing) ontology. It also asks about some less obvious affinities between the problem of the non-particulars (and their entrenchment) and Strawson’s concept of a person., Příspěvek komentuje a zpracovává na pěti stranách PF Strawson's Individuals (1959, 230 - 234) spolu s jeho ,,Entity and Identity'' a ,,Universals''. Důraz je kladen na Strawsonovo chápání jednotlivých ne-specifik jako typů nebo univerzálů, a na jeho tvrzení, že nejzřejmějšími nespecifickými entitami (,,dobře zakořeněné nešpecifické'') jsou široce pojaté artefakty včetně uměleckých děl. Úzké zaměření je na důsledky Strawsonova návrhu, že ,,vhodným modelem pro ne-detaily těchto druhů je model konkrétního modelu - určitý typ prototypu, nebo ideální příklad, který je sám o sobě, který slouží jako pravidlo nebo standard pro produkce druhých ''(1959, 233). Článek analyzuje vztah mezi postavením Strawsona a problematikou artefaktů a jejich (převážně chybějící) ontologií., and Karel Thein
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2339. Artefakty v rastrovací optické mikroskopii v blízkém poli

Creator:
Klapetek, Petr and Buršík, Jiří
Format:
bez média and svazek
Type:
model:article and TEXT
Language:
Czech
Description:
A quantitative analysis and adequate theoretical and practical steps employing a near-field scanning optical microscope (NSOM) are currently quickly developing areas of near-field optics. The basic task of the analysis consists in the correct description of tip - surface system geometry together with an electromagnetic field propagation through the system. This article deals with the results characterising tips applied in a scanning electron microscope technique and modelling field in the scanning optical microscope. Results are compared with practical measurements obtained with simple structures.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2340. Arterial pH and blood gas values in rats under three types of general anesthesia: a chronobiological study

Creator:
Pavol Švorc and Darina Petrášová
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
chronobiologie, anestezie, chronobiology, anesthesia, pH, blood gases, rats, 14, and 612
Language:
English
Description:
The aim of study was to review the status of arterial pH, pO2 and pCO2 under general anesthesias in dependence on the light-dark (LD) cycle in spontaneously breathing rats. The experiments were performed using three- to four-month-old pentobarbital(P)-, ketamine/xylazine(K/X)- and zoletil(Z)-anesthetized female Wistar rats after a four-week adaptation to an LD cycle (12 h light:12 h dark). The animals were divided into three experimental groups according to the anesthetic agent used: P (light n=11; dark n=8); K/X (light n=13; dark n=11); and Z (light n=18; dark n=26). pH and blood gases from arterial blood were analyzed. In P anesthesia, LD differences in pH, pO2, and pCO2 were eliminated. In K/X anesthesia, parameters showed significant LD differences. In Z anesthesia, LD differences were detected for pH and pO2 only. Acidosis, hypoxia, and hypercapnia have been reported for all types of anesthesia during the light period. In the dark period, except for P anesthesia, the environment was more stable and values fluctuated within normal ranges. From a chronobiological perspective, P anesthesia was not the most appropriate type of anesthesia in these rat experiments. It eliminated LD differences, and also produced a more acidic environment and more pronounced hypercapnia than K/X and Z anesthesias., P. Svorc, D. Petrášová, P. Svorc Jr., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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