Minerály řady bavenit-bohseit z pegmatitu Schinderhübel I v Maršíkově (silezikum, Česká republika)

2020 ◽  
Vol 28 (2) ◽  
pp. 353-358
Author(s):  
Zdeněk Dolníček ◽  
Miroslav Nepejchal ◽  
Milan Novák
Keyword(s):  
Czech Republic ◽  
Early Stage ◽  
Chemical Fractionation ◽  
Potential Importance ◽  
Pegmatite Body ◽  
Fluoride Complexation ◽  
Hydrothermal Stage ◽  
Ca 50 ◽  
Primary Minerals ◽  
Identical Behaviour

Bavenite and bohseite were found in an archive sample from Schinderhübel I granitic pegmatite, situated ca. 50 m NE from the famous chrysoberyl-bearing pegmatite body Schinderhübel III near Maršíkov (Silesicum, Czech Republic). Minerals of the bavenite-bohseite series together with minor quartz, muscovite and albite form chalky white radial aggregates up to 3.5 cm in size within a fissure cutting the pegmatite. The electron microprobe data revealed 29.0 - 65.4 mol. % of bavenite component, 0.03 - 0.12 apfu Na and 0.05 - 0.20 apfu F. Bavenite seems to be older than bohseite in the studied aggregate. The collected data suggest significant increase of Be/Al during growth of the studied aggregate, which could be explained in two ways. First, one can assume that different primary minerals with contrasting Be/Al ratios were dissolved during different stages of alteration (i.e., chrysoberyl in the early stage giving rise to bavenite-rich compositions and beryl during late stage giving rise to bohseite-rich members). Second, chemical fractionation of Be and Al due to complexation by fluoride anions is suggested from negative correlation between Al and F in the studied members of the bavenite-bohseite series. Identical behaviour is observed also in bavenite-bohseite from Piława Górna and Maršíkov D6e pegmatites, suggesting potential importance of fluoride complexation during hydrothermal stage of evolution of granitic pegmatites.

Milarite-group minerals from the NYF pegmatite Velká skála, Písek district, Czech Republic: sole carriers of Be from the magmatic to hydrothermal stage

2017 ◽  
Vol 29 (4) ◽  
pp. 755-766 ◽  
Author(s):  
Milan Novák ◽  
Jaroslav Cícha ◽  
Renata Čopjaková ◽  
Radek Škoda ◽  
Michaela Vašinová Galiová
Keyword(s):  
Czech Republic ◽  
Hydrothermal Stage

scholarly journals The Metallogenic Mechanism of Skarn Sn-Polymetallic Deposits in the Southern Great Khingan Range, China: Constraints on the Geological and Geochemical Characteristics of Damogutu Sn–Fe and Dashishan Sn–Pb–Zn Deposits

Minerals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 418 ◽  
Author(s):  
Shangsong Yang ◽  
Heng Wang ◽  
Xinyou Zhu ◽  
Tao Zou ◽  
Chaolei Yang ◽  
...  
Keyword(s):  
Oxygen Fugacity ◽  
Late Stage ◽  
Early Stage ◽  
Geochemical Characteristics ◽  
Evolution Process ◽  
Fine Grained ◽  
Period 2 ◽  
Hydrothermal Stage ◽  
Metallogenic Mechanism ◽  
Reducing Environment

Skarn Sn-polymetallic deposits, located in the southern Great Khingan Range, can be divided into Sn–Fe and Sn–Pb–Zn deposits. By systematically studying the geochemical characteristics of source granitoid and deposits, the ore-forming mechanisms were established, and the differences in ore-forming processes between Sn–Fe and Sn–Pb–Zn deposits are discussed. The main findings are as follows: (1) these two deposits were formed in the Late-Yanshanian period; (2) the source granitoid evolved at an early stage in a reducing environment, while the oxygen fugacity increased at a late stage through the influence of a deep-seated fault; (3) fine-grained syenogranite from Dashishan showed a higher degree of evolution than the syenogranite from Damogutu; (4) the Damogutu Sn–Fe and Dashishan Sn–Pb–Zn deposits shared a source of ore-forming fluid, and Fe, Sn, Pb, and Zn all derived from Late-Yanshanian granitoids; and (5) the ore-forming fluid experienced a continuous evolution process from the magmatic to hydrothermal stage, and the magmatic–hydrothermal transitional fluid played a very important role in skarnization and mineralization.

scholarly journals Bohseit z beryl-columbitového pegmatitu D6e v Maršíkově (silezikum, Česká republika)

2020 ◽  
Vol 28 (1) ◽  
pp. 219-223 ◽  
Author(s):  
Zdeněk Dolníček ◽  
Miroslav Nepejchal ◽  
Jiří Sejkora ◽  
Jana Ulmanová ◽  
Štěpán Chládek
Keyword(s):  
Compositional Data ◽  
Coarse Grained ◽  
Powder Diffraction Data ◽  
Unit Cell Parameters ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Pegmatite Body ◽  
Small Crystals ◽  
Hydrothermal Stage

Bohseite was found in a lenticular body of D6e beryl-columbite granitic pegmatite near Maršíkov, which is hosted by amphibole gneisses of the Sobotín Amphibolite Massif (Silesicum, northeastern part of Czech Republic). Bohseite forms chalky white aggregates up to 1 cm in size, which are hosted by small vugs in the coarse-grained pegmatite. It is associated with small crystals of quartz, adularia, albite, muscovite and epidote. Bohseite is orthorhombic, space group Cmcm with following unit-cell parameters refined from X-ray powder diffraction data: a 23.210(2), b 4.955(2), c 19.428(3) Å and V 2234.5(1.0) Å3. The electron microprobe compositional data of bohseite are presented. Bohseite from Maršíkov contains 14.3 - 42.5 mol. % of bavenite component, up to 0.06 apfu Na and 0.13 - 0.36 apfu F. The association with other beryllium-rich phases (milarite, bertrandite) points to variable activities of Be and Al during hydrothermal stage of evolution of the pegmatite body. The likely source of Be was beryl, which is sometimes completely dissolved and vugs after its crystals are lined by small crystals of above mentioned hydrothermal phases.

scholarly journals Changes of Coleopteran pests in agricultural, horticultural and ornamental plants during the 20th century

2004 ◽  
Vol 52 (4) ◽  
pp. 35-46 ◽  
Author(s):  
Hana Šefrová
Keyword(s):  
Czech Republic ◽  
20Th Century ◽  
Ornamental Plants ◽  
The Czech Republic ◽  
Ca 50

Results of an analysis of coleopteran pests in agricultural, horticultural and ornamental plants during the 20th century are given. About 115 Coleoptera taxa were registered as pests of these plants (1.9% of all species known in the Czech Republic). Of these ca 20-25 species caused regular and important and other 40 species occasional and local damages. The remaining (ca 50-55) species appeared to be economically nearly or quite irrelevant. Only small changes in the composition of important coleopteran pests were registered during the century.

scholarly journals Introducing Important Changes Concerning the Avoidance of Double Taxation Between Czech Republic and Poland

2014 ◽  
Vol 14 (2) ◽  
pp. 83-92
Author(s):  
Adam Świerczek
Keyword(s):  
Czech Republic ◽  
Interest Rates ◽  
Tax Evasion ◽  
Income Tax ◽  
Potential Importance ◽  
Double Taxation ◽  
The Czech Republic ◽  
Permanent Establishment ◽  
The Republic ◽  
Definition Of

Abstract On January 1, 2013 a new treaty between the Czech Republic and the Republic of Poland dealing with avoidance of double taxation as well as prevention of tax evasion in the field of income tax has come into effect. The treaty newly introduced the taxation of income of the permanent establishment, changes in rates of dividend taxes, interest rates and royalties, and, last but not least, what has been altered is even the definition of royalties. Furthermore, the treaty also brings a new adaptation of the profits of associated enterprises. Approval of the clause regarding exchange of information as well as cancellation of the tax-sparing clause is a novelty. This article is dealing with the description of the changes and novelties and the indication of the potential importance.

scholarly journals Factors Influencing Entrepreneurial Entry: Early-Stage Entrepreneurs in the Czech Republic

2013 ◽  
Vol 61 (2) ◽  
pp. 229-247 ◽  
Author(s):  
Martin Lukeš ◽  
Jan Zouhar ◽  
Martina Jakl ◽  
Petr Očko
Keyword(s):  
Czech Republic ◽  
Early Stage ◽  
The Czech Republic ◽  
Entrepreneurial Entry ◽  
Factors Influencing

The Timely Diagnosis and Treatment of Alzheimer’s Disease: Microsimulating Cost-Effectiveness in the Czech Republic

Demografie ◽  
2021 ◽  
Vol 63 (4) ◽  
pp. 216-225
Author(s):  
Hana M. Broulíková ◽  
Matěj Kučera ◽  
Markéta Arltová
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Czech Republic ◽  
Cost Effectiveness ◽  
Early Stage ◽  
Dominant Strategy ◽  
Diagnosis And Treatment ◽  
Net Benefit ◽  
The Czech Republic ◽  
Timely Diagnosis

Using a microsimulation model, this study evaluates the cost-effectiveness of a hypothetical policy that would increase diagnosis and treatment availability for people at an early stage of Alzheimer’s disease in the Czech Republic. If widely available, timely diagnosis and treatment would represent a dominant strategy bringing net benefit of EUR 13,751 per lifetime of each person living with this disease.

Echoing the european monetary integration in the czech republic

1998 ◽  
Vol 7 (3) ◽  
Author(s):  
Oldřich Dědek
Keyword(s):  
Czech Republic ◽  
Open Economy ◽  
Early Stage ◽  
Monetary Integration ◽  
Convergence Criteria ◽  
The Czech Republic ◽  
Catching Up ◽  
Real Convergence ◽  
High Degree ◽  
The Eu

Even in the case of an optimistic scenario of joining the EU at an early stage in the next century, CE countries are highly unlikely to participate in the take-off stage of EMU. Instead, they are expected to address some more elementary issues related to their transition processes. But the fact of being a small and open economy implies a high degree of macroeconomic discipline, in many respects not so much unlike that embedded in the Maastricht convergence criteria. Whatever disputes many surround the Maastricht convergence criteria, one can scarcely deny that they do suggest directions in which CE economies need to further upgrade their fundamentals. They put aside, however, so-called real convergence measured by the level of GDP per capita. The currency crisis in the Czech Republic delivered the lesson that the growth rates, if not underpinned by a healthy macroeconomic background, are short-lived and bring only lags Into the catching-up process.

Use of Multi-Criteria Optimization for Selection of Building Materials for Reconstruction

2014 ◽  
Vol 899 ◽  
pp. 474-478 ◽  
Author(s):  
Marcela Haliřová ◽  
Eva Rykalová
Keyword(s):  
Czech Republic ◽  
Decision Process ◽  
Building Materials ◽  
Early Stage ◽  
Evaluation Methodology ◽  
The Czech Republic ◽  
Suitable Material ◽  
Multi Criteria Evaluation ◽  
Partition Walls ◽  
Selection Of

Problematic of optimizing the selection of a suitable building material for reconstruction in the Czech Republic is a frequent topic. The paper reviews the methodology of multi-criteria evaluation of partition walls for the following criteria: the mechanical-physical, technological, economic, but also ecological. The multi-criteria evaluation methodology can be used at an early stage of construction, in the decision process of selecting the most suitable material variants for designing interior non load-bearing walls.

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