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1

Proces samo-dysproporcjowania enancjomerów podczas chromatografii kolumnowej

Wzorek Alicja, Kwiatkowska Magdalena, Urbaniak Mariusz, Gawdzik Barbara

Wiadomości Chemiczne

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2023

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[Z] 77, 5-6

425--448

EN

The review is devoted to self-disproportionation of enantiomers (SDE) phenomenon which has been observed for many different classes of chiral organic compounds. The SDE phenomenon occurs when the fractionation of an enantioenriched sample due the application of a physicochemical process under achiral conditions results in the variation of the proportion of the enantiomers present across the fractions, though the overall composition in terms of the sample ee remains unchanged. The SDE process can be considered in terms of separating the excess enantiomer from the racemate. The basic terminology related to SDE was described. The formation of the SDE under chromatographic conditions is the result of an association process occurring in a solution of a chiral, non-racemic compound. Information on preferred interactions leading to homo-/heterochiral supramolecules can be provided by quantum chemical calculations, NMR spectroscopy and comparison of crystal structures of the racemic and enantiomeric crystals. Several examples of the chromatographic experiments with different classes of compounds were given in two purposes 1) to highlight the possibility of application SDE during column chromatography as the method for enantiopurification of the chiral, non-racemic compounds; 2) to demonstrate that a standard workup (chromatographic purification, evaporation) can alter the stereochemical outcome of asymmetric reactions.

2

Dimeryzacja molekuł w wielowarstwowej fazie adsorpcyjnej na homogenicznych powierzchni stałego adsorbentu

Garbacz Jerzy K., Karpiński Karol, Kozakiewicz Mariusz

Polish Hyperbaric Research

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2019

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nr 2(67)

59--68

PL

Kontynuując dyskusję nad opisem asocjacji adsorbat-adsorbat na homogenicznych powierzchniach ciał stałych podjęto próbę sformułowania analitycznej postaci równania adsorpcji dla wielowarstwowej fazy adsorpcyjnej. Przedyskutowano zasadność założenia Berezina i Kiselewa na temat niezależności adsorpcji w warstwach dalszych od modelu zjawiska w pierwszej z nich. Wykazano zasadniczą słuszność tego założenia uwalniając je równocześnie od arbitralnego charakteru. Jako zasadniczy cel pracy przyjęto wykazanie możliwości sformułowania opisu zakładającego asocjację molekuł w całej fazie adsorpcyjnej (a nie tylko w pierwszej warstwie). Rozważania teoretyczne ograniczono do przypadku dimeryzacji w zakresie koncentracji usprawiedliwiającym przybliżenie właściwe modelowi Berezina i Kiselewa. Otrzymane finalne równanie adsorpcji wykazuje fizycznie akceptowalne właściwości brzegowe; przy odpowiednich założeniach sprowadza się do równania Brunauera, Emmetta i Tellera, równania sformułowanego wcześniej przez jednego z autorów niniejszej pracy lub równania Langmuira.

EN

Continuing the discussion on the description of adsorbate-adsorbate association on homogeneous surfaces of solids, an attempt was made to formulate an analytical form of adsorption equation for a multilayer adsorption phase. The validity of Berezin's and Kiselev's assumptions concerning the independence of adsorption in further layers from the model of the phenomenon in the first of them was discussed. The fundamental validity of this assumption has been demonstrated, simultaneously ridding it of its arbitrary character. The main aim of the study was to demonstrate the possibility of formulating a description assuming molecule association in the entire adsorption phase (and not only in the first layer). Theoretical considerations are confined to the case of dimerisation in the concentration range thus warranting the approximation characteristic of the Berezin and Kiselev model. The obtained final adsorption equation exhibits physically acceptable boundary properties; with adequate assumptions it amounts to the Brunauer, Emmett and Teller equation, the equation formulated earlier by one of the authors of this paper or the Langmuir equation.

3

Inefficiency of data mining algorithms and its architecture: with emphasis to the shortcoming of data mining algorithms on the output of the researches

Tesema Workineh

Applied Computer Science

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2019

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Vol. 15, no 3

73--86

EN

This review paper presents a shortcoming associated to data mining algorithm(s) classification, clustering, association and regression which are highly used as a tool in different research communities. Data mining researches has successfully handling large amounts of dataset to solve the problems. An increase in data sizes was brought a bottleneck on algorithms to retrieve hidden knowledge from a large volume of datasets. On the other hand, data mining algorithm(s) has been unable to analysis the same rate of growth. Data mining algorithm(s) must be efficient and visual architecture in order to effectively extract information from huge amounts of data in many data repositories or in dynamic data streams. Data visualization researchers believe in the importance of giving users an overview and insight into the data distributions. The combination of the graphical interface is permit to navigate through the complexity of statistical and data mining techniques to create powerful models. Therefore, there is an increasing need to understand the bottlenecks associated with the data mining algorithms in modern architectures and research community. This review paper basically to guide and help the researchers specifically to identify the shortcoming of data mining techniques with domain area in solving a certain problems they will explore. It also shows the research areas particularly a multimedia (where data can be sequential, audio signal, video signal, spatio-temporal, temporal, time series etc) in which data mining algorithms not yet used.

4

Renaturalizacja łąk pochodzących z zasiewu na zrekultywowanym terenie kopalni siarki „Jeziórko”

Kostuch R., Maślanka M., Kostuch J.

Inżynieria Ekologiczna

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2015

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Nr 44

19--25

PL

Streszczenie Na zdewastowanych eksploatacją siarki terenach kopalni „Jeziórko”, przeprowadzona została rekultywacja oraz zagospodarowanie łąkarskie znacznej części pokopalnianego obszaru. W roku 2014 przeprowadzono badania fitosocjologiczne istniejącej roślinności. Miały one pokazać jakie zmiany gatunkowe nastąpiły w runi utworzonej z mieszanek trawiasto-motylkowych i w jakich kierunkach zmierza zachodząca w tych zbiorowiskach sukcesja roślinna. Wyniki przeprowadzonych badań wskazują, że z upływem czasu zachodzą zmiany gatunkowe w zasianej runi prowadzące to do jej renaturalizacji. Ruń upodobnia się do zbiorowisk roślinnych z jakimi mamy do czynienia na trwałych użytkach zielonych, gdzie wykształcone są typowe dla ekosystemów trawiastych asocjacje roślinne.

EN

The terrain of the Sulphur mine of “Jeziórko” new Tarnobrzeg was recultivated by seeding grasslands on the larger part of the area. In 2014 phitosociological researches were conducted on the vegetation of the grasslands. The aim of the research was to determine botanical composition and indicate the plants that succeeded in the area. It was found that with years, botanical composition of grasslands was totally different form the original composition of seeds used. The changes lead to the reneutralization of grassland swards which change from the areas which are regularly mowed. After a number of years without mowing, the plant associations were the same as on natural grassland ecosystems.

5

Oktakarboksyftalocyjaniny – związki o interesujących właściwościach spektralnych, fotochemicznych i katalitycznych

Nackiewicz J., Suchan J., Kliber M.

Chemik

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2014

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Vol. 68, nr 4

369--376

PL

Przedstawiono metody syntezy oktakarboksyftalocyjanin, MPcOC. Omówiono ich widma absorpcyjne UV-Vis, asocjację oraz wybrane właściwości fotochemiczne i katalityczne. Opisano wpływ czwartorzędowych soli amoniowych na widma UV-Vis i asocjację CuPcOC, fluorescencję roztworów wodnych ZnPcOC oraz aktywność katalityczną CoPcOC w homogenicznym aerobowym utlenianiu L-cysteiny.

EN

The article presents synthesis methods of octacarboxyphthalocyanines, MPcOC. Their UV-Vis absorption spectra, their association and selected photochemical and catalytic properties are also discussed. Moreover, the article describes the impact of quaternary ammonium salts on UV-Vis spectra and CuPcOC association, fluorescence of aqueous solutions of ZnPcOC and catalytic activity of CoPcOC in homogeneous aerobic oxidation of L-cysteine.

6

Topographic differences play a limited role on species distribution in a sub-tropical forest in South China

Gong G.-Q., Huang Z.-L., Ye W.-H., Cao H.-L., Lian J.-Y., Lin G.-J., Wei S.-G., Li L., Bin Y., Kong B., Li B.-W.

Polish Journal of Ecology

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2013

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Vol. 61, nr 3

477--491

EN

Habitat association test has been regarded as an effective way to evaluate the relative role of niche differentiation in a community. Topographical attributes are often selected as surrogates of niche processes. However, the inference for relative role of niche differentiation is likely problematic if the spatial dependence of plant community on underlying spatially structured topographic variables is not accounted for. In this study, we used the torus shift and principal component analysis (PCA) to resolve this problem, and tested the habitat associations by adjusted-SD test in a sub-tropical evergreen broad-leaved forest in south China. The result revealed that minority of 100 common species were specialist, among which 8 species associated with first two PC axes (accounted for 98% of total eigenvalue and contributed mainly by mean elevation and aspect) and 22 species associated with last two PC axes (contributed by slope and convexity). In conclusion, we found the niche processes represented by topographical attributes play a limited role in the Dinghushan sub-tropical evergreen broad-leaved forest plot. Further study should include more habitat variables to examine the habitat associations.

7

Zjawiska dysocjacji i asocjacji towarzyszące reakcjom przeniesienia protonu między C-kwasami i zasadami organicznymi w rozpuszczalnikach aprotonowych

Nowak I., Binkowska I., Stańczyk-Dunaj M., Jarczewski A.

Wiadomości Chemiczne

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2008

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[Z] 62, 1-2

67-95

EN

The proton transfer reactions in solutions have attracted the attention of a number of laboratories for many years. These processes seem to be quite simple as they proceed without perturbation of bounding electrons and have low steric demands what enables study of their mechanism. However, many factors influences the mechanisms of these reactions. Among them and not the trifling ones, are dissociation-association effects accompanying them. The definition, behavior and reactivity of carbon acids (C-acids) depending on the type of electron withdrawing group are given [1-57]. Also the values of dissociation constants of C-acids in protic and aprotic solvents are collated in Tables 4, 5 and 7 [11, 38, 49]. The nature of products, free ions and ion pairs, of proton transfer reactions of various C-acids and strong organic bases are carefully discussed. Also their spectral characteristics are given. The equilibria and the possible routes between the substrates and the products of these reactions are also shown [58-66]. The reasons of the homoconjugation effects as a result of an association of the ionic products of the proton transfer reactions in different solvents are discussed in the context of their solvation abilities [67-86]. The formation constants of the homoconjugation complexes of amidine and guanidine bases in relation to their pK? values are quoted in Table 6 [87-95]. The nature of heteroconjugation complexes formed as the result of hydrogen bonding of different entities in the system of proton transfer reactions is discussed [96-116]. The pK? values of a number of C-acids, derivatives of nitromethane, measured in acetonitrile by potentiometric method, are given in Table 7. The pK? values of these derivatives measured in DMSO/H2O systems are compared with those obtained in acetonitrile [18, 38]. The general view of these problems is discussed and carefully reviewed.

8

Opposite-sex sibling recognition in adult root vole, Microtus oeconomus Pallas : phenotype matching or association?

Sun P., Zhu W., Zhao X.

Polish Journal of Ecology

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2008

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Vol. 56, nr 4

701-708

EN

Hypothesis of phenotype matching and association are the most likely mechanisms in kin recognition. These hypotheses were tested by observing behavioral responses of cross-fostered root voles to urine cues from familiar and unfamiliar kin and non-kin. In experiment I, approach latency by males was significantly longer in response to non-sibling reared together (NSRT) than to non-sibling reared apart (NSRA) females, whereas, investigatory and sniffing time were significantly less in response to NSRT than to NSRA. However females showed no event bias to odors from NSRT and NSRA males. In experiment II, the behavioral responses of males and females to urine odors from siblings reared apart (SRA) and NSRA were not related to the degree of genetic relationship. It was concluded that: Association mechanism is used by male root voles in opposite-sex sibling recognition; Female voles possibly adopt multiple recognition mechanisms in different social tests.

9

Deos the Red-backed Shrike (Lanius collurio L.) benefit from nesting in the association with the Barred Warbler (Sylvia nisoria Bechst.)?

Goławski A.

Polish Journal of Ecology

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2007

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Vol. 55, nr 3

601-604

EN

The co-occurrence of Redbacked Shrikes (Lanius collurio) and Barred Warblers (Sylvia nisoria) was monitored during the years 1999-2003 at 343 ha of agricultural landscape of eastern Poland. Each year 25-31 pairs of Red-backed Shrikes and 3-8 pairs of Barred Warblers were nesting. In total, during five seasons, shrikes were nesting in the vicinity (within 50 m from the centre of the Barred Warbler territory) of 22 out of 24 (92%) warbler territories. The breeding success of the pairs nesting close to Barred Warbler territories was 89%, as compared with 61% for the remaining pairs and it was statistically significant. No difference was found in the clutch size between Redbacked Shrikes nesting close to Barred Warblers and far from them, but statistically significant difference was found in numbers of fledglings between them. The present results imply that close nesting of these two species reduces the risk of nest predation. This may be due to the aggression of Barrred Warblers towards potential predators, as this species actively attacks predators near the nest.

10

Tensammetry of homogeneous mono-, di- and tri- ethoxydodecylethers

Borkowska M., Szymański A., Łukaszewski Z.

Chemia Analityczna

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2007

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Vol. 52, No. 6

1059-1069

EN

The behaviour of mono-, di- and tri-ethoxydodecyl ethers (CI2E1. C12E2 and CI2E3. respectively) under the conditions of the adsorptive stripping tensammetry (AdST) and adsorptive stripping indirect tensammetric technique (AdS-ITT) was investigated. Tcnsammetric curves of C12EI, C12E2 and C12E3 recorded towards the calhodic direction are complex due to the association of surfactants. A triple, poorly shaped tensammetric peak appears for all three surfactants. It transforms into a double peak and then into a single peak with growing bulk surfactant concentration. An additional narrow and well shaped peak appears at the more negative potential with respect to the triple peak, when a certain threshold surface concentration is exceeded. The positions of both the triple peak and the narrow peak for particular surfactants are different and shift towards the cathodic direction in the sequence C12E K C12E2 < C12E3. The calibration curves for C12E l. C12E2 and C12E3. made under the the AdST conditions with the I80-s preconccntration. follow an adsorption isotherm. However, the irregularities caused by the association phenomena are remarkable. The calibration curves for C12E1, C12E2 and C12E3, made by the AdS-ITT with the 60-s preconcentration, show a very narrow dynamic response range.

PL

Zbadano zachowanie się eterów mono-, di- i tri-etoksydodecylowych (odpowiednio C12E l, C12E2 i C12E3) w warunkach tensammetrii z adsorpcyjnym zatężaniem (AdST) oraz techniki pośredniego pomiaru tensammetrycznego z adsorpcyjnym zatężaniem (AdS-ITT). Uzyskane katodowe krzywe tensammetrycznc C12E l, Cl 2E2 i C12E3 wykazywały /łożony przebieg na skutek asocjacji badanych związków. Wszystkie trzy związki (worząpotrójny źle ukształtowany pik stopniowo przekształcający się w podwójny pik a następnie w pojedynczy pik, w miarę wzrostu stężenia surfaktanta w roztworze. Po przekroczeniu określonego progowego stężenia surfaktanta w roztworze, na krzywych pojawia się dodatkowy wąski dobrze ukształtowany pik położony w kierunku katodowym w stosunku do potrójnego piku. Zarówno potrójny jak i wąski pik uiegająprzesunieciu w kierunku katodowym w szeregu: C12E1

11

Wyznaczanie stałych multimeryzacji kwasów ftalocyjaninowych w roztworach wodnych

Nackiewicz J., Hurek J., Suchan A., Wacławek W.

Chemistry-Didactics-Ecology-Metrology

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2002

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R. 7, NR 1-2

85--89

PL

Omówiono metody wyznaczania stałych i stopnia multimeryzacji ftalocyjanin z widm absorpcyjnych VIS. Przedstawiono wyznaczanie stałej dimeryzacji molekuł oktakarboksyftalocyjaniny miedzi(II) w roztworze wodnym. Przeprowadzona analiza statystyczna uzyskanego dopasowania widm zmierzonych do „obliczonych” potwierdza poprawność przyjętej metody obliczeniowej dla wyznaczenia stałej dimeryzacji.

EN

The methods of evaluation of both phthalocyanine multimerization constants and multimerization degree from VIS absorption spectra are discussed. The evaluation of dimerization constant of copper(II) octacarboxyphthalocyanine molecules in aqueous solution is presented. Statistical analysis of the experimental and calculated spectra fit confirms the reliability of the calculation method applied for the evaluation of the dimerization constant.