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1

Półilościowe pomiary zawartości węglanu wapnia w historycznych zaprawach gipsowych, za pomocą fourierowskiej spektroskopii w podczerwieni

Koochakzaei Alireza, Mehrabad Mahsa Saidi, Ajorloo Bahram

Cement Wapno Beton

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2023

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R. 28, nr 2

68--75

PL

Niniejsza praca, wykorzystuje spektroskopię fourierowską w podczerwieni, do półilościowego pomiaru zawartości węglanu wapnia, w historycznych zaprawach gipsowych. Badano 17 próbek historycznych zapraw gipsowych, związanych z Łukiem Alishāha w Tabriz w Iranie, pochodzących z okresu Ilchanidów. W badaniach, zastosowano spektroskopię fourierowską, rozproszonego odbicia w podczerwieni - DRIFTS [ang. diffuse reflectance infrared Fourier transform spectroscopy]. Przygotowano zaprawy gipsowe zawierające od 0 do 6,5% kalcytu i zbadano je za pomocą spektrometru FTIR. Krzywą kalibracji przygotowano na podstawie stosunku intensywności pasma 1485 cm-1, związanego z wibracjami wiązań grup węglanowych w kalcycie do intensywności pasma przy 660 cm-1 odpowiadającego wibracjom grupy siarczanowej w gipsie. Obliczenia zawartości węglanu wapnia w badanych historycznych zaprawach gipsowych pokazują, że jego zawartość mieściła się w zakresie 0,12% do 1,08%. Zgodnie z uzyskanymi wynikami można przyjąć, że ze względu na niewielką ilość węglanu wapnia w zaprawach, węglan dostał się do zapraw, jako zanieczyszczenie z gleby, lub w postaci rozpuszczonych soli. Może to wskazywać, że wbrew początkowym przypuszczeniom na temat niektórych z tych zapraw, mieszanka wapna i gipsu nie była używana, jako główny składnik, w ich produkcji.

EN

This paper uses Fourier transform infrared spectroscopy to semi-quantitatively measure the amount of calcium carbonate in historical gypsum mortars. 17 historical mortar samples related to Arch of Alishāh in Tabriz-Iran, belonging to the Ilkhanid period, were evaluated. The methodology used in this study was diffuse reflectance infrared Fourier transform spectroscopy [DRIFTS]. Gypsum mortars containing 0-6.5% calcite were prepared and analysed using an FTIR spectrometer. The calibration curve was prepared based on the band intensity ratio of 1485 cm-1 related to carbonate vibrations in calcite to 660 cm-1 corresponding to sulphate vibrations in gypsum. Calculating the amount of carbonate in all historical mortars shows the presence of about 0.12 to 1.08% carbonate in gypsum mortar. According to obtained results, it can be acknowledged that due to the meagre amount of carbonate in the mixture of mortars, the existing carbonate has entered the mortar as an impurity through soil or dissolved salts. This can indicate that, contrary to the initial idea about some of these mortars, lime and gypsum mixture was not used as the main component in the making these mortars.

2

Regressive-transgressive cyclothem with facies record of the re-flooding window in the Late Silurian carbonate succession (Podolia, Ukraine)

Łuczyński P., Kozłowski W., Skompski S.

Acta Geologica Polonica

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2015

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Vol. 65, no. 3

297--318

EN

The term “re-flooding window” was recently proposed as a time-interval connected with the transgressive stage of present day peri-reefal development. In the analysis presented here, a fossil record of a re-flooding window has been recognized. Nine Late Silurian carbonate sections exposed on the banks of the Dnister River in Podolia (Ukraine) have been correlated base on bed-by-bed microfacies analysis and spectral gamma ray (SGR) measurements. Correlated were sections representing settings ranging from the inner part of a shallow-water carbonate platform to its slope, through an organic buildup. The reconstructed depositional scenario has been divided into six development stages, with the first three representing a regressive interval and the latter three a transgressive interval of the basin’s history. The re-flooding window has been identified at the beginning of a transgressive part of the succession. Surprisingly, it is characterized by an extremely fast growth of a shallow, tide-dominated platform and by deposition of calciturbiditic layers in a more basinal area. The interpreted succession is a small-scale model illustrating the reaction of carbonate depositional sub-environments to sea level changes and determining the facies position of the stromatoporoid buildups within the facies pattern on a Silurian shelf. The use of SGR analyses in shallow water, partly high-energy, carbonate facies, both for correlation purposes and for identifying depositional systems, is a relatively new method, and thus can serve as a reference for other studies of similar facies assortment.

3

Analiza korelacji pomiędzy miąższością serii łupkowej a zasobnością CU serii węglanowej we fragmencie jednego ze złóż CU-AG LGOM

Wójtowicz J.

Górnictwo Odkrywkowe

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2014

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R. 55, nr 2-3

92--96

PL

Wcześniejsze badania nad wykształceniem litologicznym i zasobnością Cu złóż LGOM-u, wskazują na istnienie zależności pomiędzy miąższością serii łupkowej a zasobnością Cu serii węglanowej. Statystyczna analiza miąższości serii łupkowej i zasobności Cu serii węglanowej wskazuje na dużą zmienność tych parametrów oraz występowanie w zbiorze danych wartość anomalnych. Analiza siły korelacji z wykorzystaniem współczynników Pearsona i Spearmana przyniosła na ogół statystyczny istotne, choć relatywnie bardzo małe wartości współczynników korelacji, które na wartość bezwzględną są rzędu 0,15.

EN

Earlier studies on lithological structure and accumulation index of Cu in LGOM deposits showed a relationship between thickness of shale ore and accumulation index of Cu in the carbonate ore. Statistical analysis of the thickness of shale ore and accumulation index of Cu in the carbonate ore indicates a high variability of these parameters and occurrence in the dataset anomalous values. The correlation testing using Pearson and Spearman coefficients generally resulted in a statistically significant but relatively very poor results with correlation coefficients slightly exceeding 0.15.

4

Reactive distillation for multiple-reaction systems: optimisation study using an evolutionary algorithm

Keller T., Dreisewerd B., Górak A.

Chemical and Process Engineering

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2013

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Vol. 34, nr 1

17--38

EN

Reactive distillation (RD) has already demonstrated its potential to significantly increase reactant conversion and the purity of the target product. Our work focuses on the application of RD to reaction systems that feature more than one main reaction. In such multiple-reaction systems, the application of RD would enhance not only the reactant conversion but also the selectivity of the target product. The potential of RD to improve the product selectivity of multiple reaction systems has not yet been fully exploited because of a shortage of available comprehensive experimental and theoretical studies. In the present article, we want to theoretically identify the full potential of RD technology in multiple-reaction systems by performing a detailed optimisation study. An evolutionary algorithm was applied and the obtained results were compared with those of a conventional stirred tank reactor to quantify the potential of RD to improve the target product selectivity of multiple-reaction systems. The consecutive transesterification of dimethyl carbonate with ethanol to form ethyl methyl carbonate and diethyl carbonate was used as a case study.

5

Reconstructions of the early and middle Holocene climate and environment based on [delta^13]C and [delta^18]O records in biogenic carbonates; Lake Niepruszewskie, western Poland

Apolinarska K.

Acta Geologica Polonica

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2009

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Vol. 59, no. 3

359-370

EN

The present study investigates environmental conditions during sediment accumulation in Lake Niepruszewskie, western Poland. Palaeolimnological reconstructions are based on stable isotope composition ([delta^13]C and [delta^18]O) of a wide range of biogenic carbonates occurring in the sediments, including shells of several gastropod species and the bivalve genus Pisidium, carapaces of ostracods belonging to the subfamily Candoninae and encrustations and oogonia of the aquatic macrophyte genus Chara. According to the radiocarbon dates obtained, accumulation of the sediment sequence began in the early Atlantic and terminated in the early Subboreal. Both [delta^13]C and [delta^18]O records reveal significant and frequent fluctuations that are attributed to repeated changes in the Lake Niepruszewskie water balance. However, conditions of prevailing long water residence time, accompanied by high productivity within the lake, are reflected in a [^13]C-enriched carbon-isotope record. Minimum [delta^13]C and [delta^18]O values were recorded for the earliest Atlantic and maximum values characterize the interglacial optimum during the middle and late Atlantic. Discrepancies observed between isotope records of particular taxa reflect the specific season and subhabitat of each carbonate secretion. [^13]C-enriched Chara encrustations and oogonia are consistent with their precipitation within the photic zone, which is commonly [^13]C-enriched due to the photosynthetic activity of macrophytes and phytoplankton. The carbon isotope composition of Lymnaea auricularia shells indicates that breathing behaviour leaves its imprint on [delta^13]C in snail shells. In aquatic air-breathing pulmonate gastropods this results in [^13]C-depletion in shells. Isotope records of individual shells of two snail species, Valvata piscinalis and Gyraulus laevis, indicate that in order to obtain mean [delta^13]C and [delta^18]O values that are representative of a 5 cm thick sampling interval, stable isotope signatures of more than five shells must be obtained.

6

Visean and Bashkirian ammonoids from Central Iran

Hairapetian V., Korn D., Bahrami A.

Acta Geologica Polonica

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2006

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Vol. 56, no. 3

229-240

EN

Two successions of Carboniferous sedimentary rocks in Central Iran yielded ammonoid assemblages from one horizon each. In the Ramsheh section, a siltstone with Neoglyphioceras yazdii n. sp. and Dombarites can be assigned to the latest Visean. The assemblage from the Shesh Angosht Mountain is more diverse with species of the genera Proshumardites, Eumorphoceras, Homoceras, Glaphyrites, Syngastrioceras, and Dombarocanites. This is the first time that the co-occurrence of the genera Eumorphoceras and Homoceras has been recorded. This fauna contains elements of the South Urals and Central Asian occurrences of Bashkirian ammonoids and suggests close palaeobiogeographic relationships.

7

Dithiocarbonate and trithiocarbonate complexes derived from VV, MoVI, ReVII tetraoxothioprecursors

Dessapt R., Simonnet-Jegat C., Secheresse F.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

15-25

EN

Reactions of MoS(2)/(4), MoO(2)S(2)(2-), MoO(2)(4), ReSJ, ReO-(4), VS(3)/(4), and VO(3-)(4) with CS(2) are described. The syntheses and X-ray determinations of (NEt(4))(2) [Mo2(S)(2) (Mo(2) S)(2) (u -S)(2)], space group P2(1)/C, a = 9.3169(3) A,b = 16.3211(5) A, c = 22.8415(5) A, Beta = 92.590(1)°, V = 3469.8(2) A3, R = 0.0898 for 8720 independent reflections and (NEt(4))(2)[Mo(2)(O)(2)(Mi - S)(mi - O)(n(2) - COS(2)2] 0.5 CS(2), space group P2(1)/C, a = 9.8190(1) A, b = 20.6313(13) A, c = 15.7193(3) A, Beta = 92.353(1)°, V = 3181.71(8) A(3), R = 0.0576 for 5760 independent reflections are presented. A rationalization of the syntheses is discussed and the structure of (NH4)[HCOS(2) is described, space group Pca2i, a = 8.3174(9) A, b = 5.6562(6) A, c = 10.7125(12) A, V = 503.97(9) A3, R = 0.0402 for 952 independent reflections. (13)C NMR data for trithiocarbonate and dithiocarbonate complexes are presented.

8

The Solid state postpolycondensation of poly(bisphenol a carbonate) in the presence of thermally unstable poly(propylene carbonate)

Kuran W., Dębek C., Wielgosz W., Kuczyńska L., Sobczak M.

Polish Journal of Chemical Technology

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1999

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Vol. 1, nr 1

26-30

EN

The process for the synthesis of high-molecular-weight poly(bisphenol A carbonate) (PBC) by the solid-state postpolycondensation (SSP) process using 5-20 wt % of thermally unstable poly(propylene carbonate) (PPC) was investigated and compared with the analogous process without addition of the thermally unstable polymer. An application of poly(propylene carbonate) for the SSP process was found to enable the process to be carried out with poly(bisphenol A carbonate) not being precrystallized prior to postpolycondensation. It does mean that the inconvenient stage of crystallization of the prepolymer could be omitted. PBC of M v 48 000 g/mol was obtained by the standard procedure of SSP process starting with a prepolymer crystallized in acetone (for 192 h at a condensation temperature of 230-255°C and pressure of 0.07 mmHg). Instead, in the presence of 20 wt % PPC (without the inconvenient phase of crystallization of the prepolymer), PBC of Mv 42 000 g/mol with inconspicuous content of PPC was obtained. The results have been discussed in terms of propylene carbonate appearing in the postpolycondensation system due to the thermal decomposition of poly(propylene carbonate) under conditions applied. Propylene carbonate probably acts as a swelling agent which makes the prepolymer chain mobility and increased crystallization as well as the removal of condensation low-molecular-weight by-products more facile.

9

Electric conductivity of concentrated LiAsF6 solutions at temepratures from -25°C to 25°C in equimolar propylene carbonate-acetonitrile mixture

Werblan L., Augustyniak R., Bok M.

Polish Journal of Applied Chemistry

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1998

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Vol. 42, nr 3-4

219-227

EN

The characteristics of specific conductiviy, x, were studied in concentrated lithium hexafluoroarsenate solutions in equimolar mixture of propylene carbonate, PC, and acetonirile, AN, in the concentration range from 0.28 to 1.21 mol. kg-l at temperatures -25, -15, -10, -5,0,5, 10,15,18,20 and 25°C. The results were analysed in terms of Casteel-Amis equation; the maximum conductivity values, Xmax' and corresponding concentrations, m max' were calculated.