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Artigo Revisado por pares

Tarmo Kiipli, T Kallaste, Viiu Nestor, David K. Loydell,

... TARMO KIIPLISearch for more papers by this authorTOIVO KALLASTE, TOIVO KALLASTESearch for more papers by this authorVIIU ... TARMO KIIPLISearch for more papers by this authorTOIVO KALLASTE, TOIVO KALLASTESearch for more papers by this authorVIIU ... 00162.xCitations: 13 T. Kiipli [[email protected]], T. Kallaste [[email protected]], V. Nestor [[email protected]], Institute of ... colleagues. Learn more.Copy URL Abstract Kiipli, T., Kallaste, T., Nestor, V. & Loydell, D.K. 2010: Integrated ...

Tópico(s): Geological and Geochemical Analysis

2009 - Wiley | Lethaia

Artigo Revisado por pares

E Kiipli, Tarmo Kiipli, T Kallaste,

... by this author on: GSW Google Scholar T. Kallaste T. Kallaste 1Institute of Geology, Tallinn University of Technology, Ehitajate ... Search Site Citation E. Kiipli, T. Kiipli, T. Kallaste; Reconstruction of currents in the Mid-Ordovician–Early ...

Tópico(s): Paleontology and Stratigraphy of Fossils

2009 - Geological Society of America | Geology

Artigo Revisado por pares

Madis Lõhmus, Kalle Kallaste, Bruno Le Bizec,

Thyreostatic compounds could be illegally administered to animals in order to obtain a weight gain due to a higher retention of water in the edible tissue and the gastro-intestinal tract. In the European Union their use for animal production is banned since 1981. Recently a highly sensitive method exploiting the determination of thyreostats with 3-iodobenzylbromide prior to purification to determine thyreostats in urine and other matrices was reported. For the first time, the UPLC instrumentation ...

Tópico(s): Insect and Pesticide Research

2009 - Elsevier BV | Journal of Chromatography A

Artigo Acesso aberto Revisado por pares

T Kallaste, Tarmo Kiipli,

Sanidine composition of 130 samples of bentonites from 12 sections of Telychian (some possibly Sheinwoodian) age was analysed by X-ray diffractometry for correlation purposes.Solid solution of magmatic sanidine contained 20-47% NaAlSi 3 O 8 molecules.The sanidine composition is very individual for many beds and can be used successfully for correlations.

Tópico(s): Paleontology and Stratigraphy of Fossils

2002 - Estonian Academy Publishers | Proceedings of the Estonian Academy of Sciences Geology

Artigo Revisado por pares

Charles Woolfson, Dace Calite, Epp Kallaste,

ABSTRACT This article examines employee ‘voice’ in workplace health and safety in three Baltic New Member States by means of a cross‐national survey. The data point to unresolved problems of voice in the context of rather poor working environments. These present opportunities for collective renewal by trade unions, but paradoxically are more likely to be addressed by employers in the context of significant labour shortages created by a post‐European Union accession labour ‘exit’.

Tópico(s): Social Policy and Reform Studies

2008 - Wiley | Industrial Relations Journal

Artigo Revisado por pares

Rutt Hints, Kalle Kirsimäe, Peeter Somelar, T Kallaste, Tarmo Kiipli,

The mineral composition of altered volcanic ash beds, bentonites, deposited in marine environments is typically characterized by smectite or illite–smectite type clay minerals. Silurian bentonites from an unmetamorphosed normal marine sedimentary sequence in the eastern Baltic Palaeobasin, however, show a complex and varied mineral composition with illite–smectite, K-feldspar and kaolinite as the dominant authigenic phases. The whole-rock XRD study of 52 bentonite beds from two drill-cores — Ruhnu ...

Tópico(s): Geochemistry and Elemental Analysis

2008 - Elsevier BV | Sedimentary Geology

Artigo Revisado por pares

Tarmo Kiipli, Lennart Jeppsson, T Kallaste, Ulf Söderlund,

Silurian bentonites from Sweden and the eastern Baltic are correlated using XRD analysis of sanidine composition. Identifying the same bentonite in different sections has constrained correlations between the conodont, graptolite and chitinozoan zonations. Three bentonites correlate the Cyrtograptus murchisoni Zone with the upper part of the Pterospathodus amorphognathoides Zone and both the Lower and the Upper Pseudooneotodus bicornis conodont biozones at their type locality. Thus the base of the ...

Tópico(s): Geology and Paleoclimatology Research

2008 - Geological Society of London | Journal of the Geological Society

Artigo Acesso aberto Revisado por pares

T Kallaste, E Kiipli, Tarmo Kiipli, K Orlova,

Thirty suspected altered volcanic ash (bentonite) samples from the Nässumaa-825 and Orissaare-859 sections were analysed by the X-ray fluorescence method.Twenty of these samples revealed chemical signs of pure volcanogenic material, one was of mixed terrigenous-volcanogenic origin, and nine were classified as terrigenous claystones.Twenty of the bentonites were correlated, with variable confidence, with bentonites from earlier studied sections; one sample represents a formerly unknown eruption.New ...

Tópico(s): Geological Formations and Processes Exploration

2008 - Estonian Academy Publishers | Proceedings of the Estonian Academy of Sciences Geology

Artigo Revisado por pares

Tarmo Kiipli, Sigitas Radzevičius, T Kallaste, Vykintas Motuza, Lennart Jeppsson, Linda Wickström,

Abstract Seven Wenlock bentonite beds from four drill cores in Lithuania with sufficient thickness for sampling were analysed by XRD and XRF. The sanidine composition of bentonites combined with graptolite biozonation of the host rock were used for correlations. Two of the studied bentonite samples at the antennulariuslflexilis biozone boundary can be confidently correlated between two Lithuanian sections. Four of the studied bentonites can be correlated with lower or higher probability with earlier ...

Tópico(s): Clay minerals and soil interactions

2008 - Taylor & Francis | GFF

Artigo Acesso aberto Revisado por pares

E Kiipli, Tarmo Kiipli, T Kallaste, Leho Ainsaar,

Baltoscandian Middle and Upper Ordovician carbonate rocks are relatively poor in phosphorus, with the P 2 O 5 content of 0.05-0.5%,rarely exceeding 1%.Phosphorus distribution in the Ordovician carbonate succession shows spatial and temporal variations.In the Estonian Shelf P content is the highest in the Middle Ordovician, close to the Tremadocian P-rich siliciclastic sediments, decreasing towards younger carbonate rocks.In the basinal, i.e. deep shelf, sections two intervals of elevated P contents ...

Tópico(s): Astro and Planetary Science

2010 - Estonian Academy Publishers | Proceedings of the Estonian Academy of Sciences Geology

Artigo Revisado por pares

Krista Jaakson, Epp Kallaste,

Based on eight in-depth case studies, this paper argues that telework transfers bigger (and legally unbinding) responsibility to employees whereas both employees and employers accept it. This is likely due to the fact that adoption of telework alters some aspects of psychological contract between employees and employers.

Tópico(s): Employment and Welfare Studies

2010 - Wiley | New Technology Work and Employment

Artigo Revisado por pares

Tarmo Kiipli, T Kallaste, Viiu Nestor,

Abstract Sanidine composition and bulk geochemistry of volcanic ash beds from the East Baltic indicate the subalkaline nature of the volcanism near the margins of the Baltica plate during the Silurian. Several bentonites in the Wenlock include a previously unknown sanidine with 48 to 58 mol % of the Na+Ca component. In contrast to the earlier Telychian volcanism, sodium-rich sanidine occurs in ash beds which originate from relatively moderately evolved dacitic magma. The studied material from two ...

Tópico(s): Hydrocarbon exploration and reservoir analysis

2010 - Cambridge University Press | Geological Magazine

Artigo Revisado por pares

Tarmo Kiipli, Алвар Соэсоо, T Kallaste, E Kiipli,

In the Telychian section of Estonia and Latvia K-bentonites from 45 volcanic eruptions were discovered. The thickness of K-bentonite interbeds varies from a few millimetres to 20 cm. The sodium component concentration in sanidine phenocrysts measured by XRD ranges from 20 to 48 mol% and was used for establishing correlations. The Ti, Zr, Nb, Th and Sr concentrations and ratios show temporal trends indicating fractional crystallization in magma chambers. The analysis of biotite phenocrysts revealed ...

Tópico(s): Geochemistry and Geologic Mapping

2007 - Elsevier BV | Journal of Volcanology and Geothermal Research

Artigo Revisado por pares

Janek Reinik, Ivo Heinmaa, Uuve Kirso, T Kallaste, Johannes Ritamäki, Dan Boström, Éva Pongrácz, Mika Huuhtanen, William Larsson, Riitta L. Keiski, Krisztián Kordás, Jyri‐Pekka Mikkola,

Environmentally friendly product, calcium–silica–aluminum hydrate, was synthesized from oil shale fly ash, which is rendered so far partly as an industrial waste. Reaction conditions were: temperature 130 and 160 °C, NaOH concentrations 1, 3, 5 and 8 M and synthesis time 24 h. Optimal conditions were found to be 5 M at 130 °C at given parameter range. Original and activated ash samples were characterized by XRD, XRF, SEM, EFTEM, 29Si MAS-NMR, BET and TGA. Semi-quantitative XRD and MAS-NMR showed that ...

Tópico(s): Concrete and Cement Materials Research

2011 - Elsevier BV | Journal of Hazardous Materials

Artigo Acesso aberto Revisado por pares

Tarmo Kiipli, R Einasto, T Kallaste, V Nestor, H Perens, S Siir,

Nine altered volcanic ash samples from the shoal and lagoonal sediments of the Rootsiküla Stage (Wenlock-Ludlow boundary interval, Estonia) were analysed, compared and correlated with five samples of deep sea environments from Latvia.Volcanic ash correlations indicate that the Wenlock-Ludlow boundary correlates with the boundary of the Viita and Kuusnõmme beds, i.e., it is significantly lower than proposed earlier.The distribution of chitinozoans supports this new correlation.Geochemical data indicate ...

Tópico(s): Geology and Paleoclimatology Research

2011 - Estonian Academy Publishers | Proceedings of the Estonian Academy of Sciences Geology

Artigo Revisado por pares

Tarmo Kiipli, T Kallaste,

Abstract Fifty-nine Wenlock and uppermost Llandovery bentonite samples from the Estonian and Latvian Aizpute drill-core sections were studied by analysing magmatic sanidine composition by XRD. On the basis of sanidine composition and geochemical data the Estonian bentonites can be grouped into six types, which probably reflect different volcanic sources. These bentonites originate from 33 different eruptions, 16 of which can be recognised on the basis of their sanidine composition. Four bentonites ...

Tópico(s): Geology and Paleoclimatology Research

2006 - Taylor & Francis | GFF

Artigo Revisado por pares

Enli Kiipli, Tarmo Kiipli, T Kallaste,

Abstract Pyroclastic sanidine composition is used for correlation of the Osmundsberg bentonite (O-bentonite) bed from Estonia to Latvia. Chemical changes during conversion of volcanic ash to authigenic silicates in shallow and deep shelf sediments differ, leading to the formation of kaolinite-rich bentonite in deep shelf and feldspar-rich bentonite in shallow shelf environments. The Rumba Formation in Estonia is proved to be of Lower Telychian age. Firmly based correlation between shallow and deep ...

Tópico(s): Geochemistry and Elemental Analysis

2006 - Taylor & Francis | GFF

Artigo Revisado por pares

Rutt Hints, Kalle Kirsimäe, Peeter Somelar, T Kallaste, Tarmo Kiipli,

The Baltic Ordovician–Silurian sedimentary succession embodies numerous altered volcanic ash beds that are illite–smectite dominated. Only a few beds rich in chlorite–smectite are known from the Upper Ordovician Pirgu Stage of Estonia. Mixed-layer chlorite–smectite occurs commonly in low-grade metamorphic and hydrothermal environments. However, chloritic K-bentonites of the Pirgu Stage have never been buried deeply and lack signs of metamorphic overprinting. In order to understand the origin of ...

Tópico(s): Paleontology and Stratigraphy of Fossils

2006 - Elsevier BV | Sedimentary Geology

Artigo Revisado por pares

Enli Kiipli, Tarmo Kiipli, T Kallaste, S Siir,

In the Fennoscandian Shield the fluctuations in arid–humid climate conditions are inferred from the Al2O3/TiO2 ratio of the clay fraction of Estonian carbonate rocks of the Baltoscandian sedimentary Basin. The Late Ordovician climate of the Fennoscandian Shield was mainly semi-humid with several humid pulses in the Sandbian, mid-Katian and Hirnantian. The post-Hirnantian climate was fluctuating between humid and arid until stable humid conditions were established in the Middle and early Late Llandovery. ...

Tópico(s): Paleontology and Stratigraphy of Fossils

2012 - Elsevier BV | Palaeogeography Palaeoclimatology Palaeoecology

Artigo Revisado por pares

Jonne Kotta, Mart Simm, Ilmar Kotta, Inga Kanošina, Kalle Kallaste, Tiit Raid,

Tópico(s): Marine and coastal ecosystems

2004 - Springer Science+Business Media | Hydrobiologia

Artigo Revisado por pares

E Kiipli, Tarmo Kiipli, T Kallaste,

The occurrence of black shale in deep shelf environments, chertification in shoreward carbonate facies, barite occurrences, positive δ13C excursions in carbonate sections and enhanced micritic limestone accumulation give evidence of a primary bioproductivity rise suggesting upwelling in the Aeronian of the East Baltic. The end-Rhuddanian onset of the rise in primary bioproductivity corresponds to the beginning of black shale formation on the deep shelf and micritic limestone formation on the shallower ...

Tópico(s): Geochemistry and Elemental Analysis

2004 - Elsevier BV | Palaeogeography Palaeoclimatology Palaeoecology

Artigo Revisado por pares

J Nemliher, G. N. Baturin, T Kallaste, И. О. Мурдмаа,

Tópico(s): Bone health and osteoporosis research

2004 - Pleiades Publishing | Lithology and Mineral Resources

Artigo Acesso aberto Revisado por pares

T Kallaste, T Kurvits, J Nemliher, I Puura,

An XRD study of heat-treated shell samples of the lingulate brachiopod Obolus apollinis Eichwald from the upper Cambrian (Furongian) of NW Russia (basal Tosna Formation, Lava River section) revealed the presence of two phases of apatite persisting the temperatures from 200 to 700 °C.At higher temperatures, 900 and 1000 °C, only one phase was detected.The lattice parameters of the two phases suggest possible preservation of carbonate-hydroxylapatite within the compact laminae of initially organo-phosphatic ...

Tópico(s): Marine and environmental studies

2004 - Estonian Academy Publishers | Proceedings of the Estonian Academy of Sciences Geology

Artigo Revisado por pares

Enli Kiipli, T Kallaste, Tarmo Kiipli,

Abstract Hematite and goethite were determined by X-ray diffractometry using natural goethite and hematite for calibration. The subtraction of diffractograms before and after ignition at 500[ddot]C was applied for goethite identification and quantification, and ZnO was used as internal standard for the matrix correction. Red terrigenous claystones from deep shelf facies revealed co-occurrences of hematite and goethite, on average 1.7% hematite and 0.6% goethite. Grey claystones from the onshore ...

Tópico(s): Geochemistry and Elemental Analysis

2000 - Taylor & Francis | GFF

Artigo Revisado por pares

Tarmo Kiipli, Peter Dahlqvist, T Kallaste, Enli Kiipli, Jaak Nõlvak,

Abstract Altered volcanic ash interbeds (bentonites) in the upper Katian of Baltoscandia indicate significant volcanic activity in neighbouring tectonically active areas. Katian bentonites in the East Baltic can be reliably correlated using sanidine phenocryst composition. Ratios of immobile trace elements TiO 2 , Nb, Zr and Th to Al 2 O 3 enable extension of the correlations to Scandinavia, where late diagenetic alterations could have caused recrystallization of sanidine phenocrysts. At least seven ...

Tópico(s): Geochemistry and Geologic Mapping

2014 - Cambridge University Press | Geological Magazine

Artigo Acesso aberto Revisado por pares

Merle Küttim, Marianne Kallaste, Urve Venesaar, Aino Kiis,

There is a growing interest in entrepreneurship education expressed by politicians, higher education institutions and students. Entrepreneurship education has been shown to contribute to the development of students’ entrepreneurial intentions, although the findings are not entirely conclusive. The theoretical foundation of the current paper was the theory of planned behavior, TPB (Ajzen, 1991, Ajzen, 2005). The aim of the study was to identify the content of university entrepreneurship education ...

Tópico(s): Family Business Performance and Succession

2014 - Elsevier BV | Procedia - Social and Behavioral Sciences

Artigo Acesso aberto Revisado por pares

Urve Venesaar, Marianne Kallaste, Merle Küttim,

There is currently a strong global drive towards encouraging a greater proportion of students to consider and pursue venture creation as an alternative graduate career path (Nabi, Holden, & Walmsley, 2006; Leffel & Darling, 2009). Previous studies have shown that a small proportion of students are founding their enterprises before graduation and those enterprises are relatively small, primarily micro-enterprises with a modest turn-over (Fueglistaller et al., 2009). The purpose of this article is to study ...

Tópico(s): Private Equity and Venture Capital

2014 - Elsevier BV | Procedia - Social and Behavioral Sciences

Artigo Acesso aberto Revisado por pares

M VOOLMA, Алвар Соэсоо, Sigrid Hade, Rutt Hints, T Kallaste,

This paper describes vertical fine-scale geochemical heterogeneity of Estonian graptolite argillite (GA).GA samples from Pakri and Saka outcrop sections were collected at 20 cm intervals for chemical analysis of major and trace elements, including rare earth elements.The study indicates GA enrichment in U, V, Mo and Pb with respect to the average black shales and thus confirms the formerly reported data on GA geochemistry in general.However, the content of enriched elements and other trace metals ...

Tópico(s): Geochemistry and Geologic Mapping

2013 - Estonian Academy Publishers | Oil Shale

Artigo Revisado por pares

Tarmo Kiipli, T Kallaste, E Kiipli, Sigitas Radzevičius,

Abstract This article presents a dataset of geochemical analyses from Silurian altered volcanic ash beds (bentonites) characterising 132 eruptions and preserved in sedimentary sections of the East Baltic area. TiO2, Nb, Zr, Th, Y, Ce, Cr and V ratios with Al2O3 are used for identifying correlations between ash beds from Scandinavian sections. Some correlated ash beds are illustrated by schematic maps of areal distribution indicating volcanic sources from directions of both Iapetus and Rheic palaeo- ...

Tópico(s): Hydrocarbon exploration and reservoir analysis

2013 - Taylor & Francis | GFF