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Start Over Subject Geologie. Meteorologie. Klimatologie

92. Characteristics of wind-induced waves in a shallow water zone

Creator:
Spanilá, Tamara and Jahoda, Karel
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, vlny, waves, height, length and time-period of the waves, energy of waves, 7, and 551
Language:
English
Description:
The parameters determine waves energy in shallow water zone that pronounces the crucial influence on abrasion of both natural and artificially paved banks. The effort to re-development of the relations was found as absolutely necessary for waves energy calculations. Substantial benefit of the work is found not only in enabling the use of computers while avoiding time-consuming and difficult application of diagrams, but namely in recent recognition that the calculation results showed a risk of underestimate the real impact of wind-induced waves. In some cases, the calculations respecting the above standard produce lower values of waves height and time-period and thus also lower values of wave energy., Tamara Spanilá and Karel Jahoda., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

93. Characterization and differentiation of kaolinites from selected Czech deposits using infrared spectroscopy and differential thermal analysis

Creator:
Lenka Vaculíková, Eva Plevová, Silvie Vallová, and Ivan Koutník
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, infračervená spektroskopie, infrared spectroscopy, kaolinite, degree of structural order, thermogravimetry and differential thermal analysis, 7, and 551
Language:
English
Description:
This paper reports the possibilities of using FTIR spectroscopy and simultaneous thermogravimetry and differential thermal analysis for examination of the structural order of four Czech kaolinite samples (Jimlikov, Sedlec, Olomucany and Unanov deposits) and one kaolinite standard KGa-1b from Georgia deposit obtained from the Source Clays Repository of The Clay Minerals Society (USA). FTIR spectroscopy was used for the classification of the degree of structural order of kaolinite samples by empirical (IR-E) and numerical (IR-N) classification. Differential thermal analysis was used for the determination of the kaolinite disorder degree according to decomposition peak temperature obtained from DTA curves. The resulting trend of decrease in orderliness is: KGA-1b (with the best orderliness) > Jimlikov > Sedlec > Olomucany > Unanov (with the worst orderliness)., Lenka Vaculíková, Eva Plevová, Silvie Vallová and Ivan Koutník., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

94. Characterization of anthropogenic influence on the soil cover on selected localities of Prague

Creator:
Žigová, Anna, Martin Šťastný, Jana Krejčová, and Hájek, Pavel
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, jílové minerály, clay minerals, soil development, clay mineralogy, anthropogenically affected areas of Prague, loess, hot-water extractable carbon, 7, and 551
Language:
English
Description:
The character of soil cover in anthropogenically affected areas was determined on the basis of soil morphology, particle size distribution, soil chemical properties, soil organic matter properties and mineralogy of clay fraction. The degree of anthropogenic influence was variable in the individual soil profiles. This is probably the first time that data on hot-wate rextractable carbon distribution in soil profile were obtained from the territory of Prague., Anna Žigová, Martin Šťastný, Jana Krejčová and Pavel Hájek., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

95. Characterization of surface acidity and catalytic ability of natural clay minerals by means of test catalytic reaction

Creator:
Novikova, Lyudmila, Belchinskaya, Larisa, Roessner, Frank, and Alsawalha, Murad
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, jílové minerály, clay minerals, test catalytic reaction, methylbutynol conversion, surface acidity, 7, and 551
Language:
English
Description:
Catalytic test reaction of methylbutynol (MBOH) conversion was applied to investigation of natural clays and non-clay minerals from Jordanian (bentonite, kaolinite, diatomite, zeolit e) and Russian (palygorskite, kaolinite, hydromica) deposits as well as H-ZSM-5. Palygorskite and kaolinite containing samples have shown the highest catalytic activity. Conversionove r Jordanian clay minerals decreased in the order: zeolite > bentonite > red kaolinite > white kaolinite > diatomite that agreed to change of acidity, surface area of samples. Sufficient deactivation was observed for H-ZSM-5, kaolinite and hydromica due to adsorption of secondary product in micropores of raw minerals. Products of both acidic and basic pathways of test reaction were formed indicating the presence of acid and basic sites on clays surface, apart from acidic catalyst H-ZSM-5. Theyield ratio of acidic to basic products was above the unity for zeolite, bentonite, red kaolinite, and palygorskite; equal to unity for diatomite and hydromica, and less then unity for white kaolinite. It was observed for kaolinite containing sample that high activation temperature increased conversion of MBOH owing to fo rmation of additional basic sites as a result of mineral dehydroxylation. Rise of montmorillonite content from 30 to 80 % provided 91-97 % of MBOH conversion., Lyudmila Novikova, Larisa Belchinskaya, Frank Roessner and Murad Alsawalha., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

97. Clarifying geological structure for coal and marsh gas development using magnetotelluric method

Creator:
Asaue, Hisafumi, Sasahara, Misahito, Yoshinaga, Toru, Obara, Yuzo, Uchida, Kagemi, and Matsumoto, Hiroyuki
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, těžba uhlí, coal mining, apparent resistivity, cretaceous formation, Kushiro city, Osotsunai fault, Harutori fault, 7, and 551
Language:
English
Description:
Magnetotelluric (MT) and audio-magnetotelluric (AMT) methods were applied to clarify the deep geological structure in a coal-mining area in Kushiro, southeastern Hokkaido, Japan. These methods are effective in surveying to deep. Onedimensional inversion was applied to the measurement data obtained in the MT and AMT surveys to estimate the resistivity distributions in the study area. In addition, the one-dimensional inversion method was improved to obtain accurate results by including a smoothing factor and Akaike’s Bayesian information criterion. The inversion method revealed that the lowresistivity zones at depths between 100 and 120 m below sea level correspond with the Yubetsu coal-bearing formation and clay layer, and the thickness of Cretaceous strata was estimated to be more than 4000 m. Finally, the dip of the Osotsunai fault was estimated., Hisafumi Asaue, Misahito Sasahara, Toru Yoshinaga, Yuzo Obara, Kagemi Ushida and Hiroyuki Matsumoto., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

98. Clays from Vila Nova da Rainha (Portugal): appraisal of their relevant properties in order to be used in construction ceramics

Creator:
Coroado, João F., Ferraz, Eduardo, Gomes, Celso F., and Rocha, Fernando
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, jíly, keramické suroviny, clay, ceramic raw materials, Vila Nova da Rainha, construction ceramics, 7, and 551
Language:
English
Description:
The clay deposit of Vila Nova da Rainha (VNR) is included in the lithostratigraphic formation named "Argilas de Tomar", and is located at the lower section of the Tertiary Tagus’ river basin. Clay from one quarry is being extracted for the production of construction ceramics. In this work the firing transformations undergone by VNR clays containing quartz, alkaline feldspar, iron oxy-hydroxides, and clay minerals have been studied. Carbonates have not been identified in these raw materials. The clay layers can be subdivided in three groups based upon composition and ceramic properties. The first group, VNR0, is represented by smectite-kaolinite sandy-silty clay, the second group (VNR1 and VNR2) corresponds to illite-kaolinite bearing clay and the third group (VNR3 and VNR4) is represented by illite-smectite silty clay. The firing process involves the formation of hematite and mullite both influencing the technical properties of the fired products. With regards to the ceramic properties assessed at 1100 ºC the first group showed the lowest total shrinkage value (7.35 %) the highest water absorption value (12.2 %) and the lowest mechanical bending strength value (12.0 MPa); the same properties assessed in the second group provided the highest firing shrinkage values (7.0-5.0 %), the lowest values of water absorption (0.1-0.2 %) and relatively high mechanical bending strength values (47.8-48.0 MPa); the third group showed firing shrinkage values within the range 3.5-4.2 %, water absorption values within the range 1.4-4.5 %, and the highest mechanical bending strength values (49.2-52.0 MPa). The results of the ceramic properties being appraised indicate that the raw materials being studied are suitable for the production of high-quality construction ceramics, such as brick, roof tile and rustic floor tile., João F. Coroado, Eduardo Ferraz, Celso F. Gomes and Fernando Rocha., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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