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1

Mechanisms of electrical conductivity, quantum capacity and negative capacitance effects in InSe (PTHQ) nanohybrid

Ivashchyshyn Fedir, Maksymych Vitaliy, Calus Dariusz, Klapchuk Myroslava, Baryshnikov Glib, Galagan Rostislav, Litvin Valentina, Chabecki Piotr, Bordun Ihor

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 1

art. no. e139958

EN

In this work, we present findings on the syntheses and study of properties of InSe < PTHQ > nanohybrid. The introduction of guest component in GaSe matrix leads to an increase in inhomogeneities, which is clearly confirmed by the strengthening of the low-frequency horizontal branch of Nyquist diagrams. A constant magnetic field counteracts this effect and changes the behavior of the impedance hodograph at low frequencies to the opposite. Illumination leads to a colossal increase in quantum capacitance, which is clearly demonstrated in the Nyquist diagram. For the synthesized InSe < PTHQ > nanohybrid the interesting behavior of the current-voltage characteristic is reported. As a result of studies of the synthesized InSe < PTHQ > nanohybrid the effect of “negative capacity” is observed, the magnitude of which can be controlled by the electric field. Based on the constructed impedance model and proposed N-barrier model, the physical mechanisms of the investigated processes are suggested.

2

Oxalate Intercalated Mg/Cr Layered Double Hydroxide as Adsorbent of Methyl Red and Methyl Orange from Aqueous Solution

Badri Arini Fousty, Juleanti Novie, Palapa Neza Rahayu, Hanifah Yuliza, Mohadi Risfidian, Mardiyanto, Lesbani Aldes

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 3

71--81

EN

Mg/Cr layered double hydroxide (LDH) has been successfully synthesized by means of the coprecipitation method followed by the intercalation process using oxalate to form Mg/Cr-oxalate. The materials were characterized using XRD, BET, and FTIR and then applied as an adsorbent of anionic dyes i.e. methyl red (MR) and methyl orange (MO). MR and MO adsorption was studied through variations of adsorption time, concentration, temperature, desorption process, and adsorbent regeneration. The XRD characterization results showed an increase in the interlayer distance from 7.62 Å to 11.35 Å after the intercalation process. The increase of interlayer space of Mg/Cr-oxalate is also equal to the BET data, which shows an increase in surface area from 21.511 m2/g to 49.270 m2/g. The kinetics and isotherm parameters of MR and MO adsorption using Mg/Cr LDH and Mg/Cr-oxalate showed the same results following the PFO kinetics model and Langmuir isotherm model with R2 close to one. Mg/Cr LDH has the adsorption capacity for MR and MO up to 61.728 mg/g 54.645 mg/g, respectively. In turn, the highest adsorption capacity is achieved by Mg/Cr-oxalate for MR adsorption at 81.235 mg/g and MO at 71.429 mg/g. The thermodynamic parameters of MR and MO adsorption using Mg/Cr LDH and Mg/Cr-oxalate indicate that the adsorption process is endothermic and spontaneous.

3

Study of methylene blue adsorption by modified kaolinite by dimethyl sulfoxide

Lellou Salima, Kadi Samir, Guemou Laid, Schott Jacques, Benhebal Hadj

Ecological Chemistry and Engineering. S

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2020

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Vol. 27, nr 2

225--239

EN

Tamazert kaolin was modified with dimethyl sulfoxide (DMSO). The starting material and resulting from the intercalation were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Intercalation caused considerable changes in our clay by increasing the basal spacing to 11.22 Å, an intercalation rate of 98 %. The adsorption of methylene blue was studied as a function of pH, contact time, temperature, dye concentrations and adsorbents. Kinetic data have been adequately described by the pseudo-second order and intraparticle scattering model. The adsorption isotherm is in good agreement with the Redlich-Peterson model. A change in thermodynamic values (ΔH°, ΔS° and ΔG°) was observed after intercalation. Adsorption became non-spontaneous exothermic and ordered.

4

Studies of Poly(Acrylic Acid-co-Maleic Acid) Sodium Salt Intercalated Montmorillonite

Grabowska B., Cukrowicz S., Kurleto-Kozioł Ż., Kaczmarska K., Drożyński D., Sitarz M., Bobrowski A.

Archives of Foundry Engineering

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2019

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iss. 4

67--75

EN

The intercalation into interlayer spaces of montmorillonite (MMT), obtained from natural calcium bentonite, was investigated. Modification of MMT was performed by the poly(acrylic acid-co-maleic acid) sodium salt (co-MA/AA). Efficiency of modification of MMT by sodium salt co-MA/AA was assessed by the infrared spectroscopic methods (FTIR), X-ray diffraction method (XRD) and spectrophotometry UV-Vis. It was found, that MMT can be relatively simply modified with omitting the preliminary organofilisation – by introducing hydrogel chains of maleic acid-acrylic acid copolymer in a form of sodium salt into interlayer galleries. A successful intercalation by sodium salt of the above mentioned copolymer was confirmed by the powder X-ray diffraction (shifting the reflex (001) originated from the montmorillonite phase indicating an increase of interlayer distances) as well as by the infrared spectroscopy (occurring of vibrations characteristic for the introduced organic macromolecules). The performed modification causes an increase of the ion exchange ability which allows to assume that the developed hybrid composite: MMT-/maleic acid-acrylic acid copolymer (MMT-co- MA/AA) can find the application as a binding material in the moulding sands technology. In addition, modified montmorillonites indicate an increased ability for ion exchanges at higher temperatures (TG-DTG, UV-Vis). MMT modified by sodium salt of maleic acid-acrylic acid copolymer indicates a significant shifting of the loss of the ion exchange ability in the direction of the higher temperature range (500–700°C).

5

Wpływ opóźniaczy węglowodanowych na ograniczenie złego wpływu minerałów ilastych na właściwości dyspergujące superplastyfikatorów polikarboksylanowych

Tan H., Deng X., Gu B., Ma B.

Cement Wapno Beton

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2018

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R. 21/83, nr 1

16--29

PL

W pracy zbadano wpływ węglowodanów sacharozy oraz maltodekstryny na skuteczność działania domieszek polikarboksylanowych w zaczynach zawierających montmorillonit. W tym celu oznaczano konsystencję zaczynów oraz oceniono stopień adsorpcji PCE oraz węglowodanów w zawiesinie montmorillonitu na podstawie całkowitej zawartości węgla organicznego. Oba węglowodany zmniejszały dodatek PCE potrzebny do uzyskania założonej płynności zaczynów o kilkanaście procent i ograniczały zmniejszanie się konsystencji w czasie. Zarówno sacharoza jak i maltodekstryna nie wbudowują się pomiędzy warstwy montmorillonitu, ale w niewielkim stopniu ograniczają interkalację PCE, najprawdopodobniej dzięki wiązaniom wodorowym cząsteczek węglowodanów z bocznymi łańcuchami poli(tlenku etylenu).

EN

The effect of two carbohydrate retarders i.e. sugar and maltodextrin on the clay tolerance of PCE was investigated in this study. The fluidity loss of cement-montmorillonite paste was tested to assess the clay tolerance of PCE. Adsorption of PCE and carbohydrate in montmorillonite suspension was assessed with Total Organic Carbon measurements. On the basis of several methods application the interaction of carbohydrates with montmorillonite was discussed. Carbohydrates addition is reducing the addition of PCE needed to reach the same initial fluidity level of cement paste. Also the consistency loss is decreased by addition of carbohydrates. The results showed that nor sugar neither maltodextrin can be intercalated between montmorillonite layers. However, they have a slight effect on hindering the intercalation of PCE, most probably, due to the hydrogen bonds between carbohydrate and long side chain of PEO.

6

Dendrimeric peptide – montmorillonite intercalation compound

Kędzierski M., Janiszewska J., Moszumańska I.

Polimery

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2016

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T. 61, nr 10

677--682

EN

The solution intercalation method was used for immobilization of low-molecular-mass lysine--based peptide dendrimers (Lys-D, hydrochloride form) on montmorillonite (MMT). The intercalation was confirmed by X-ray diffraction and elemental analysis of the products. Analysis of Brunauer-Emmett-Teller (BET) nitrogen adsorption–desorption isotherms indicates that both interlayer and external clay surfaces are involved in the binding of dendrimeric peptides. Depending on the structure of Lys-D, including the location of protonated amino groups in peptide branches, the intercalation involves ion exchange between sodium montmorillonite and peptide ionic groups or proceeds leaving the intact peptide counterions. Thermogravimetric analysis (TGA) studies of MMT-Lys-D compounds indicate that the major mass-loss associated with the decomposition of peptide component is shifted to higher temperatures compared to the peptide itself.

PL

Metodą interkalacji z roztworu przeprowadzono immobilizację niskocząsteczkowych dendrymerów L-lizyny (Lys-D, w formie chlorowodorku) na montmorylonicie (MMT). Wyniki analizy metodą dyfrakcji rentgenowskiej (XRD) oraz analizy elementarnej (C, H, N, Cl) potwierdziły interkalację peptydu w MMT. Na podstawie analizy izoterm adsorpcji–desorpcji azotu Brunauera-Emmetta-Tellera (BET) stwierdzono, że związanie peptydu następuje zarówno w przestrzeni międzywarstwowej, jak i na zewnętrznej powierzchni MMT. W zależności od struktury peptydu Lys-D i położenia protonowanych grup aminowych interkalacja połączona jest z wymianą jonową pomiędzy montmorylonitem sodowym i peptydem lub przebiega z zachowaniem wyjściowych przeciwjonów chlorkowych Lys-D. Analiza TGA związków MMT-Lys-D wskazuje, że główny ubytek masy związany z rozkładem składnika peptydowego zachodzi w wyższym zakresie temperatury niż w przypadku peptydu niezwiązanego.

7

Materiały hybrydowe montmorylonit-indometacyna/naproksen: otrzymywanie, dobór optymalnych warunków interkalacji i charakterystyka

Rapacz-Kmita A., Stodolak-Zych E., Bućko M. M., Ziąbka M.

Materiały Ceramiczne

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2016

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T. 68, nr 3

267--273

PL

Celem pracy była ocena możliwości wykorzystania montmorylonitu (MMT), jako potencjalnego nośnika leków o ujemnym potencjale elektrokinetycznym, tj. indomatacyny i naproksenu, mających działanie przeciwzapalne i przeciwbólowe. Nośniki leków na bazie montmorylonitu otrzymano poprzez interkalację leków w materiałach w formie proszków w procesie 24-godzinnego mieszania zawiesiny surowca w roztworze wodnym wraz z rozpuszczonym lekiem w temperaturach 20 °C, 50 °C i 80 °C. Uzyskane materiały badano pod kątem ilości i sposobu wprowadzenia leku w strukturę montmorylonitu. Zmiany potencjału elektrokinetycznego otrzymanych koniugatów (materiał hybrydowy MMT-lek) w stosunku do wyjściowego montmorylonitu określono, wykonując pomiar potencjału zeta. Ocenę możliwości wprowadzenia leków w przestrzenie międzypakietowe MMT przeprowadzono z wykorzystaniem dyfraktometrii rentgenowskiej (XRD) i spektroskopii w podczerwieni (FTIR). Obserwacji zmian morfologii proszków po interkalacji lekiem dokonano przy wykorzystaniu skaningowej mikroskopii elektronowej (SEM). Wyniki badań potwierdziły możliwość wbudowania leków w strukturę minerału, jednakże ujemny potencjał elektrokinetyczny leków uniemożliwiał całkowitą ich interkalację pomiędzy warstwy montmorylonitu. Na proces interkalacji miała wpływ temperatura procesu. Najkorzystniejsza z punktu widzenia procesu interkalacji okazała się temperatura 50 °C.

EN

The aim of the study was to investigate the use of montmorillonite (MMT) as a potential drug carrier. Two medicines with a negative electrokinetic potential were selected for intercalation of montmorillonite, namely indomethacin and naproxen, having anti-inflammatory and analgesic properties. Montmorillonite-based drug carriers were prepared by a 24 hours stirring of suspension with an aqueous solution of both dissolved drugs at 20 °C, 50 °C and 80 °C. The obtained materials were tested for the amount and ways of incorporation of the drug in the montmorillonite structure. Changes in electrokinetic potential of the obtained carriers (MMT-drug hybrids) as compared to the starting montmorillonite were determined by measuring the zeta potential. The presence of the drug introduced into the interlayer spaces of MMT was examined using the following measurement methods: X-ray diffraction (XRD), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results confirmed the possibility of drug incorporation into the structure of the mineral. The efficiency of intercalation was found to be depended on the temperature of process, and the most preferred one from that viewpoint was the processing at a temperature of 50 °C. However, the negative zeta potential of the drug prevented the complete intercalation of the drug between the layers of montmorillonite.

8

Layered double hydroxides as transesterificationcatalysts and nanofillers for polyester resin

Kędzierski M., Bończa-Tomaszewski Z., Jaworska G., Niska A.

Polimery

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2015

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T. 60, nr 3

160--166

EN

Saturated polyester resins were prepared by reaction of dimethylterephthalate with alkylene glycols in the presence of layered doublehydroxides (hydrotalcites, HT). The effect of HT composition (cation and aniontypes) on the rate and progress of transesterification was investigated. It was found that zinc-aluminum HT intercalated with anionic form of aminolauric acid[HT(ZnAl)ALA] efficiently catalyzes transesterification process, increasing therate of reaction or lowering its temperature when compared to the reaction with use of conventional organic tin catalyst. The polyester resin obtained in this way is transparent, which along with X-ray diffraction data indicates the delamination of clay layers and formation of nanocomposite. The limitation of using ALA-intercalated HT as an additive for polyesters used in coatings is coloration of the resin with an increase of the reaction temperature above 180°C. Colorless polyester was obtained using more thermally stable hydrotalciteintercalated with ethylenediaminetetraacetic acid, however, at the expense of significantly longer reaction time. Using HT(ZnAl)ALA catalyst a two-step synthesis of carboxyl polyester resin was performed and the obtained product was used as a component of powder coating formulation.

PL

Przeprowadzono syntezę nasyconych żywic poliestrowych w reakcji tereftalanu dimetylowego z glikolami alkilenowymi, w obecności warstwowego podwójnego wodorotlenku typu hydrotalkitu (HT). Analizowano wpływ składu HT na szybkość i wydajność transestryfikacji. Najlepsze wyniki (zwiększenie szybkości reakcji lub obniżenie średniej temperatury procesu w porównaniu z szybkością i temperaturą reakcji prowadzonej w obecności tradycyjnego katalizatora organocynowego) uzyskano z zastosowaniem hydrotalkitu interkalowanego kwasem aminolaurynowym (ALA). Otrzymane w taki sposób żywice były transparentne, co w połączeniu z zanikiem refleksów hydrotalkitu w widmie XRD produktu transestryfikacji może świadczyć o utworzeniu się delaminowanego nanokompozytu. Wykorzystanie HT interkalowanego ALA w żywicach poliestrowych stosowanych do powłok jest ograniczone ze względu na zabarwienie pojawiające się w temperaturze powyżej 180 °C. W reakcji prowadzonej z udziałem bardziej stabilnego termicznie hydrotalkitu modyfikowanego kwasem etylenodiaminotetraoctowym otrzymano bezbarwny poliester, jednak kosztem znacznego wydłużenia czasu reakcji. Katalizator HT(ZnAl)ALA zastosowano w dwustopniowej syntezie poliestru o łańcuchu zakończonym grupami karboksylowymi, który następnie użyto w charakterze składnika proszkowej kompozycji powłokowej.

9

Adsorpcja acetonu na materiałach ilastych

Pliś I., Warzybok M., Prokop W., Petrus R., Warchoł J.

Inżynieria i Ochrona Środowiska

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2015

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T. 18, nr 2

233--243

PL

Celem niniejszej pracy było porownanie adsorpcji par acetonu na węglu aktywnym i naturalnych adsorbentach opartych na bentonicie. Naturalny bentonit poddano chemicznej modyfikacji poprzez dealuminację kwasem HCl, wymianę jonową solami: chlorkiem cezu (CsCl) i bromkiem tetrametyloamoniowym (TMA-Br) oraz interkalację. Otrzymane adsorbenty zastosowano do adsorpcji par acetonu. Badania przeprowadzono w warunkach kolumnowych w specjalnie do tego celu zbudowanej instalacji laboratoryjnej, składającej się z butli zawierającej mieszaninę par acetonu w azocie o danym stężeniu, kolumny wypełnionej badanym adsorbentem, przepływomierza oraz analizatora stężeń. Pomiar stężenia acetonu na wylocie z kolumny wykonano (on-line) techniką chromatografii gazowej. Badania przeprowadzono w temperaturze otoczenia pod ciśnieniem atmosferycznym dla wejściowego stężenia acetonu równego 200 ppm. Na materiale modyfikowanym TMA-Br wyznaczono izotermę adsorpcji, którą wykorzystano do modelowania równowagi adsorpcji. Zastosowano równania empiryczne dwu-, troj- i czteroparametrowe.

EN

The aim of the present work was to compare adsorption of acetone vapors on activated carbon and natural adsorbents based on bentonite. Natural bentonite was chemically modified by acidic dealumination using HCl, by cationic exchange with cesium chloride (CsCl) and tetramethylammonium bromide (TMA-Br) salts and by intercalation. There were determined basic physical and chemical properties of the adsorbents and the investigation for acetone adsorption capacity was carried out. For comparative purposes, also active carbon (AC) was tested. The research was realized in a self-made system consisting of a bottle with acetone-nitrogen mixture with given concentration, fixed-bed column with tested adsorbent, flowmeter and concentration analyzer. Concentrations on column inlet and outlet were monitored on-line using gas chromatography technique. The tests were implemented on 0.5 g samples of active carbon, natural bentonite (B) and four modified bentonites: one treated with hydrochloric acid (B-HCl), two modified with Cs+ and TMA+ cations (B-Cs, B-TMA) and one intercalated. Samples were previously dried at 150°C for one hour. The tests were performed for atmospheric pressure, ambient temperature and inlet acetone concentration of 200 ppm. The amounts adsorbed by examined materials were calculated with integral method on the basis of obtained breakthrough curve. Non-modified bentonite (B) had much lower acetone adsorption capacity than modified ones. The determined acetone adsorption capacity followed the order: B-int > B-TMA > B-Cs > B-HCl > B. Using specific method of chemical modification, the acetone adsorption capacity level compared to AC was reached. Surface area (ABET) of AC was 10-times greater than ABET of B-TMA, but in comparison with B-TMA the adsorption capacity of AC was only doubled. Therefore, ABET should not be the only factor determining acetone adsorption onto modified bentonite, but also chemical character of the adsorbent surface ought to be taken into consideration. The isotherm for B-TMA was examined in the temperature of 30°C for vapor pressure range of 0 to 0.5 P/P0. In order to perform modeling of adsorption equilibrium, there were used obtained equilibrium concentrations of acetone in solid and gaseous state. Two-, three- and four-parametric empirical equilibrium models were applied. The non-linear curve fitting was carried out using the Levenberg-Marquardt algorithm. The relationship between two variables (experimental and theoretically predicted) was assessed by the Fisher test, the mean error and the approximation of standard deviation. The best criteria value of statistical tests proved that the best approximation of experimental data was obtained for the Redlich-Peterson model. Moreover, this model reflected the best approximation of experimentally obtained maximum adsorption capacity value (qm,exp). The value of parameter n (n ≠ 1) implied heterogeneity of the B-TMA adsorbent surface and/or multilayer adsorption.

10

Preparation and characterization of azobenzene-smectite photoactive mineral nanomaterials

Koteja A., Matusik J.

Geology, Geophysics and Environment

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2015

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Vol. 41, no. 1

99--100

EN

Smectites are 2:1 layered minerals built of one octahedral sheet located between two tetrahedral sheets. The layer charge derived from the isomorphic substitutions in the mineral structure is compensated by the interlayer cations. The capability to exchange the interlayer cations is an important property of smectites as it enables to design and produce new nanomaterials through their modification with organic compounds. Such hybrid materials are highly desirable in industry and environmental protection due to their specific properties that may be designed in nanoscale. Preparation of photoactive materials using intercalation of layered minerals, mainly synthetic micas, with azobenzene and other azocompounds was proposed previously (Fujita et al. 2003, Ogawa et al. 2003, Heinz et al. 2008). Azobenzene molecules show a change in their shape and dimensions upon the UV irradiation, what may affect the structure of host mineral. The photoactive materials may find application in nanotechnology as molecular nanoswitches and nanosensors controlled by UV radiation (Klajn 2010). The objective of this study was to prepare azobenzene-smectite intercalation compounds. The results of structural and chemical characterization of obtained materials are crucial for further improvement of their photoresponsive properties.The Na-montmorillonite (SWy), Camontmorillonite (STx), beidellite (BId) and synthetic laponite (SynL) were used in the experiments. The modification procedure involved (1) the intercalation of smectites with hexadecyltrimethylammonium bromide (C16), and (2) insertion of azobenzene into the interlayer space. The reaction with C16, in amount equal to 1.0 CEC (cation exchange capacity) of the smectite, was performed in an aqueous suspension (20 g/L) for 2 h in 60°C. The obtained organosmectites were prepared as thin films on the glass plates and reacted with azobenzene in a teflon vessel at ~100°C for 24 h. In such conditions the azobenzene vaporizes and penetrates the interlayer space of the organomineral. The azobenzene/smectite weight ratio was equal to 0.2. The chemical and structural analyses of all obtained samples were carried out using X-ray diffraction (XRD), infrared spectroscopy (FTIR), and CHN (carbon-hydrogen-nitrogen) elemental analysis. The increased amount of nitrogen and carbon in modified samples confirmed the occurrence of intercalation process of both the ammonium salt and the azobenzene. Moreover, new bands appeared in the infrared spectra of the C16-smectites at ~2924 cm−1 and ~2851 cm−1 due to the C-H stretching vibrations in the C16 molecules. The spectra of azobenzene intercalation compounds showed add it ionally a series of bands corresponding to the vibrations characteristic for the azobenzene 2015, vol. 41 (1): 99–100100molecule at ~3061 cm−1, ~1581 cm−1, ~1455 cm−1, and ~1302 cm−1. The basal spacing of tested minerals increased after the C16 intercalation, as confirmed by XRD analysis. The increase was equal to 6.1 Å, 3.3 Å, 4.1 Å and 3.5 Å for SWy, STx, BId and SynL samples, respectively. This suggests nearly horizontal arrangement of the C16 molecules and formation of a monolayer in the smectite’s interlayer space. Introduction of azobenzene lead to a further increase of d001. The increase was visibly different for all the samples and it was equal to 7.0 Å, 15.0 Å, 21.7 Å and 23.5 Å for SWy, STx, Bid, and SynL samples, respectively. The arrangement of organic molecules in the interlayer space is influenced by a number of factors including (1) type of the mineral, (2) layer charge and its location in the layer, and (3) the amount and arrangement of the cationic surfactant (Klapyta et al. 2001, Lagaly et al. 1976). A correlation between azobenzene location in the interlayer space and the photo-response behaviour of tested materials will be the subject of further studies.

11

Sorpcja lotnych związków organicznych na materiałach ilastych

Kargula M., Warchoł J.

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2014

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z. 61, nr 1

135--147

PL

Lotne związki organiczne (LZO) jest to zbiór ok. 190 substancji organicznych emitowanych do atmosfery głównie przez przemysł chemiczny i petrochemiczny jako tzw. gazy odlotowe. Skutkiem ich negatywnych oddziaływań są zmiany klimatyczne i degradacja środowiska naturalnego. Obecnie są prowadzone intensywne badania nad modernizacją istniejących instalacji oczyszczania gazów lub nad poszukiwaniem nowych efektywnych i ekonomicznych metod. Ocenia się, że ok. 10% instalacji przemysłowych do redukcji/eliminacji zanieczyszczeń w gazach odlotowych stosuje się techniki adsorpcyjne. Jest to wysoko sprawny, a zarazem prosty pod względem aparaturowym proces, który zapewnia usunięcie większości zanieczyszczeń nawet w przypadku niskich stężeń (<1 mg/dm3). Zarówno efektywność, jak i ekonomika procesów adsorpcyjnych zależą od właściwości materiału sorpcyjnego, w tym możliwości odzysku zaadsorbowanych substancji oraz wielokrotnego użycia sorbentu. W pracy zamieszczono przegląd literatury dotyczący adsorpcji lotnych związków organicznych (LZO) na naturalnych oraz aktywowanych fizycznie i chemicznie (interkalacja, pilarowanie) materiałach ilastych. Stwierdzono, że każdy sposób modyfikacji prowadzi do poprawy ich właściwości sorpcyjnych związanych ze zwiększeniem pola powierzchni właściwej oraz selektywności względem wybranych zanieczyszczeń. Perfekcyjna sorpcja LZO na materiałach ilastych zależy od polarności sorbowanych cząstek oraz rodzaju oddziaływań pomiędzy cząsteczkami a powierzchnią sorpcyjną. Te ostatnie odnoszą się do rodzaju i liczby grup funkcyjnych obecnych na powierzchni sorpcyjnej materiału. Koszty oraz efektywność procesu wskazują, że są to sorbenty, które mogą stanowić alternatywę dla powszechnie stosowanych węgli aktywnych.

EN

VOCs are important hazard chemicals present outdoor and indoor air. They are the main source of chemical and petrochemical industry, which are emitted into atmosphere in the form of waste gases. Process of flue gas cleaning was divided into: destructive and allowing recovery of undesirable compounds. Adsorption is widely accepted due to their easy operation and low cost. This methods assures the removal of most the existing VOCs even at low concentration (<1 mg/dm3). Activated carbons are generally used in many adsorption process because of their highly developed surface area and large pore volume. However, some disadvantages have been frequently encountered, such as flammability, pore clog, hygroscopicity and problems with regeneration. Therefore, scientific research are focused on searching for alternative sorption materials. This group included widespread in nature clay materials. The abundance of them and their low cost are likely to make it a strong candidate as an adsorbent for the removal of VOCs form waste gases. Various method of modification and surface activation have been investigated in order to enhance both sorbents capacity and selectivity. The review collects the research results obtained for adsorption of volatile organic compounds (VOCs) on natural as well as surface modified (by intercalation or pillaring) clay materials. The mechanism of VOCs adsorption was discussed in relation to individual adsorbent-adsorbate interactions. Valorization of clay materials identified that the clay materials price is lower as compared to activated carbon.

12

Właściwości mechaniczne i morfologia kompozytów termoelastoplastów z montmorylonitem modyfikowanym polimerem rozpuszczalnym w wodzie

Dębek C., Rajkiewicz M.

Przemysł Chemiczny

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2012

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T. 91, nr 8

1528-1531

PL

Opracowano procedury interkalacji montmorylonitu sodowego polimerem rozpuszczalnym w wodzie oraz zbadano właściwości mechaniczne i morfologię kompozytów termoelastoplastów: triblokowego kopolimeru butadienowo-styrenowego (SBS) oraz mieszaniny PP/ EPDM sieciowanej dynamicznie (TPV) z niewielkimi ilościami interkalowanego montmorylonitu. Montmorylonit sodowy interkalowano dekstryną żółtą N i plastyfikowano glicerolem. Proces interkalacji prowadzono w środowisku wodnym. Badania WAXS wykazały rozsunięcie odległości międzywarstwowej montmorylonitu. Zbadano wpływ napełniacza na właściwości mechanicznie termoelastoplastów (SBS, TPV). Stwierdzono wzmacniające działanie interkalowanego montomrylonitu. Obok kompozytów interkalowanych otrzymano w niektórych przypadkach kompozyty eksfoliowane.

EN

Na montmorillonite (MT) was intercalated with the yellow dextrin plasticized with glycerol and used as a filler (1–4% by mass) for manufg. styrene-butadiene-styrene copolymer and dynamically crosslinked polypropylene/ethylenepropylene-diene blend matrix composites. For comparison, a com. amminium salt-modified MT was also used as a filler (up to 5% by mass). The composites reinforced with the dextrin-modified MT showed higher tensile strength and elongation at break than those reinforced with the com. modified MT. In some cases, exfoliated systems were formed.

13

Synteza kompozytów poli(kwas akrylowy)-bentonit oraz poliakryloamid-bentonit do zastosowań adsorpcyjnych

Natkański P., Białas A., Kuśtrowski P.

Chemik

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2012

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Vol. 66, nr 7

742-749

PL

Naturalny bentonit poddano modyfikacji poprzez wprowadzenie do przestrzeni międzywarstwowych łańcuchów hydrożelowych na drodze polimeryzacji interkalacyjnej. Jako modyfikator organiczny został użyty poliakryloamid lub poli(kwas akrylowy). Strukturę otrzymanych połączeń przebadano metodami proszkowej dyfrakcji rentgenowskiej oraz spektroskopii w podczerwieni. Stwierdzono, że przeprowadzona modyfikacja skutkuje znaczącym wzrostem pojemności sorpcyjnej materiału względem kationów Fe(III).

EN

Raw bentonite was modified by introducing to its interlayer spaces hydrogel chains by intercalation polymerization. Poly(acrylic acid) or polyacrylamide were used as organic modifiers. The structure of the obtained compounds was examined by means of powder X-ray diffraction and IR spectroscopy. The performed modification resulted in a significant increase in the sorption capacity of the material in respect of Fe(III) cations.

14

Hyper capacity of MCM-41 supramoleculer structure in the radiofrequency range

Grygorchak I. I., Vojtovych S. A., Stotsko Z. A., Seredyuk B. A., Tovstyuk N. K.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 49, nr 2

200--203

EN

Purpose: of this paper was: 1) to synthesize supramolecular MCM-41 structure (p-cyanogen phenyl ether of n-heptyl benzoic acid - 40%)>> with inserted guested nematic and 2) to study its dielectric properties. Design/methodology/approach: Supramolecular MCM-41 structure has been synthesized by vacuum encapsulated method at room temperature. Dielectric properties have been studied by impedance spectroscopy method in the frequency range 10-3-106 Hz by “AUTOLAB” complex of “ECO CHEMIE” (Holland), supported by computer programs FRA-2 and GPES. Findings: We have found a tremendous increase of the permittivity and a low value of the tangent of angle of electric losses, as well as the appearance of low frequency inductive response. Practical implications: Super high capacitors of radio range and time-delay lines allow to use them in a direct incorporation into nanoelectronics devices as a new class of super high capacitors and nanostructured time-delay lines. Originality/value: First time we have received: 1) supramolecular structure of the configuration of molecular-lattice nonorganic matrix with a non nematic substrate, 2) significant inductive response in such structures.

15

Badanie procesu sorpcji jonów Pb i Cu na bentonicie

Fusova L., Cechlova K., Cablik V.

Inżynieria Mineralna

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2011

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R. 12, nr 1

11-18

PL

Przeanalizowano możliwość usuwanie jonów Pb2+ oraz Cu2+ z wodnego roztworu poprzez sorpcję bentonitu i modyfikację jego właściwości. Próbkę bentonitu pobrano ze złoża Branany - Cerny Vrch w Republice Czeskiej. Próbka była głównie złożona z montmorillonitu, kwarcu i syderytu. Aby poprawić jego właściwości sorpcyjne modyfikowano je poprzez interkalację (z użyciem octadecylaminy) oraz nitryfikację (roztworem 1M NaCl). Do opisu sorpcji wykorzystano modele Langmuira i Freundlicha zaadaptowane dla izoterm sorpcji Pb2+ oraz Cu2+ na czystym bentonicie i próbkach zmodyfikowanych.

EN

The removal of Pb2+ and Cu2+ from aqueous solutions by sorption onto bentonite and its modification was investigated. The bentonite sample was taken from the Branany - Cerny Vrch locality in the Czech Republic. This sample was mainly composed of montmorillonite, quartz and siderite; to improve its sorption properties it was modified by intercalation (by octadecylamine) and nitrification (by 1M NaCl). The Langmuir and Freundlich models were adopted to describe the sorption isotherms of Pb2+ and Cu2+ adsorption on the raw bentonite and modified samples.

16

Uniepalnione kompozyty epoksydowe

Oleksy M., Heneczkowski M, Mossety-Leszczak B., Galina H., Budzik G.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 5

1372-1377

PL

Przeprowadzono badania nad napełnianiem żywicy epoksydowej EpidianR 6 bentonitami Specjal i SN modyfikowanymi czwartorzędową solą amoniową (QAS). Przedstawiono wpływ sposobu i temperatury homogenizacji układów napełniacz-żywica na stopień rozsunięcia płytek napełniaczy w kompozycie podczas ich przetwarzania. Udział modyfikowanych i niemodyfikowanych glinokrzemianów zmieniano w zakresie 0,5÷5,0 % mas. Oceniono właściwości uniepalniające pod kątem stosowania tych kompozytów w elementach konstrukcji lotniczych a uzyskane wyniki badań przedstawiono w tabeli 1. Stwierdzono, że w zakresie 0,5÷1,0% mas. dodatku modyfikowanych QAS bentonitów BSN i BS (BSNQAS, BSQAS) uzyskuje się stosunkowo największy przyrost odporności kompozytów na płomień (rys. 3÷5). Efekt ten wspomagany jest także drobnopłytkową strukturą morfologii obserwowaną na kruchych przełomach za pomocą skaningowego mikroskopu elektronowego (SEM) (rys. 6 i 9).

EN

A study on filling the epoxy resin EpidianR 6 with bentonites Specjal and SN modified with a quaternary ammonium salt is presented. The effects of the procedure and homogenization temperature applied for the system resin-filler during its processing upon the degree of widening the gaps be- tween platelets of the filler in the composite. The content of both modified and unmodified aluminum silicates was changed in the range 0.5-5.0 wt.%. The fire resistance properties of the composites (shown in Table 1) were assessed from the point of view of their potential applications in aircraft elements. It was found that when the amount of the QAS modifies bentonites BSN and BS (BSNQAS, BSQAS) was in the range of 0.5÷1.0 wt.% the fire resistance of composites increased the most rapidly (Fig. 3÷5). The effect was enhanced by the tiny layered morphology of the bentonites seen in SEM microphotographs of the brittle fracture surfaces of the composites (Fig. 6 and 9).

17

Temperature dependence of electric permittivity for kaolinite and intercalated kaolinite.

Słonka T., Głowińki J., Mielcarek W., Leluk K., Orzechowski K.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

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2007

|

Vol. 46, nr 19

176-179

EN

Electric properties of natural kaolinite and kaolinite intercalated by ethylene glycol were measured and compared. We found that the intercalation considerably increases the electric permittivity. It is explained as a possible movement of polar guest molecules in the interlayer area. The dielectric data were supported by XRD and TGA experiments.

18

Transport and electrochemical properties of orthorhombic LiMnO2 cathode material for Li-ion batteries

Molenda J., Ziemnicki M., Bućko M., Marzec J.

Materials Science Poland

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2006

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Vol. 24, No. 1

75--83

EN

The aim of this paper was to determine the temperature range of thermal stability of orthorhombic LiMnO2, together with its electrical and electrochemical characterization. High-temperature studies of the electrical properties of orthorhombic LiMnO2 point to structural instability of the phase at temperatures over 400 ?C. Annealing above 400 ?C leads to its decomposition into a two-phase mixture (Li2MnO3 + LiMn2O4). Stoichiometric LiMnO2 has a very low conductivity at room temperature, which limits the effectiveness of intercalation at the initial stage. The temperature dependences of the electrical conductivity and thermoelectric power of deintercalated LiyMnO2 samples indicate a dominant electronic conductivity over the ionic one. A remarkable increase in electronic conductivity accompanied by a drop of activation energies is observed upon deintercalation. It was shown that the deintercalation of lithium from LiyMnO2 makes the structure less stable, leading to a two-phase mixture (LizMnO2 + LixMn2O4). s. 75-83, bibliogr. 4 poz.

19

Structural and transport properties of LiFe0.45Mn0.55PO4 as a cathode material in Li-ion batteries

Ojczyk W., Marzec J., Dygas J., Krok F., Liu R.S., Molenda J.

Materials Science Poland

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2006

|

Vol. 24, No. 1

103--113

EN

The paper presents investigations on structural, electrical and electrochemical properties of phosphoolivine, LiFe0.45Mn0.55PO4, synthesized at high temperatures. Moessbauer spectroscopy measurements confirmed the occurrence of iron(II), and X-ray absorption near edge structure (XANES) measurements evidenced manganese(II) and iron(II). Impedance spectroscopy enabled the separation of electrical conductivity into electronic and ionic components. The substitution of manganese for iron led to a noticeable increase in the electronic component of conductivity and only to a slight increase in the ionic component, compared to pure LiFePO4. Also, the chemical diffusion coefficient of lithium measured by GITT turned out larger in LixFe0.45Mn0.55PO4. It has been stated that the increased electronic conductivity in manganese-doped phospho-olivine activates the diffusional mechanism of lithium deintercalation.

20

Spectral Properties and DNA-binding Study of 6a, 12a-Diazadibenzo-[a,g]fluorenylium Derivative

Juskowiak B., Gałęzowska E., Kościelna H., Hermann T., Piotrowska K.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 5

831-844

EN

The DNA binding affinity and anion effect on the aggregation of a G-quadruplex selective ligand, 6a,12a-diazadibenzo-[a,g]fluorenylium derivative, were studied by UV-Vis absorption, molecular modeling and fluorescence spectroscopy. The anion character and its concentration influenced the spectral properties of ligand aggregates. Observed spectral peculiarities were discussed in terms of the formation of H- and J-type aggregates. The DNA binding mode and affinity of the ligand depended on the salt concentration; preferential binding to G-quadruplexDNAwas clearly seen at higher salt concentration.