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1

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

100%

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

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tom 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.

2

Preparation and characterization of azobenzene-smectite photoactive mineral nanomaterials

100%

Koteja A. , Matusik J.

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2015

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tom 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.

3

Badanie procesu sorpcji jonów Pb i Cu na bentonicie

75%

Fusova L. , Cechlova K. , Cablik V.

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tom 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.

4

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

75%

Badri A. F. , Juleanti N. , Palapa N. R. , Hanifah Y. , Mohadi R. , Mardiyanto , Lesbani A.

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tom 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.

5

Porównanie stałych sieciowych czteroskładnikowych chalkogenidków molibdenu

75%

Niewiarowska D. , Cybulski Z. A. , Ziółkowska D.

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tom Vol. 58, nr 9

468-470

PL

Potrójne chalkogenidki o wspólnej postaci ABX4 (A=Ti, B=Mo, X=S, Se, Te) interkalowano litem oraz miedzią. Ustalono, że związki miedzi są bardziej odporne na wpływ czynników powietrza atmosferycznego, niż interkalaty zawierające lit. Dla wszystkich rozważanych związków komórki elementarne wywskaźnikowano w układzie jednoskośnym, uzyskując bardzo dobrą zgodność pomiędzy danymi doświadczalnymi i teoretycznymi. Wyliczone wartości stałych sieciowych dobrze ze sobą korespondują z wyjątkiem stałej "a" dla LiTiMoSe4. W przypadku tellurków tytanowo-molibdenowych interkalowanych miedzią stwierdzono także, że większa średnica atomu "gościa" powoduje wzrost stałej sieciowej "c".

EN

Ternary chalcogenides with common formula ABX4 (A=Ti, B=Mo, X=S, Se, Te) were intercalated with lithium and copper. It was stated that the copper compounds were more resistant to influences of atmospheric air components then the intercalates containing lithium. Very good agreement between the experimental and theoretical data confirms that for all the compounds under discussion the elementary cells can be described in the monoclinic system. The calculated values of the lattice constants are well corresponding wite each other with the exception of the constant a for LiTiMoSe4. Moreover, in the case of titanium-molybdenum tellurides intercalated with copper it was ascertained that greater ion diameter of the "quest" atom increases the lattice constant c.

6

Adsorpcja acetonu na materiałach ilastych

63%

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

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tom 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.

7

Chemical/electrochemical methods for the preparation of graphite multiintercalation compounds

63%

Skowroński J. M. , Urbaniak J.

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tom Nr 4

238-243

EN

In this work, the process of the subsequent intercalation of HSO4H2SO4 into CrO3-GIC examined. CrO3GICICs are prepared with two different chemical methods: this is, intercalation from the CrO3/CH3COOH solution according to the Platzcr and de la Martiniere procedure and intercalation of CrO3 from Cr03/HCl solution. Furthermore, the preparation of graphite multiintercalation compound consisted with two different intercalates CrO3 and ZnCl2 from the mixture of graph ite/CrO32 HC1 was performed. The intercalation process of both intercalates CrO3 and ZnCl2 into graphite has been confirmed by cyclic voltammetric technique. Upon the successive intercalation of HSO4/H2S04 the anodic and cathodic effects characteristic for the presence of ZnCl2 and CrO3 have been served in the voltammogram. This suggests the formation of quaternary CrO3/ZnCI2-H2SO4-GIC.

PL

Przedstawiono proces biinterkalacji Hsub>2S04 zachodzący w CrO3IZG. Interkalacja CrO3 w grafit była prowadzona z dwóch mieszanin: grafit/Cr03/HCl oraz grafit/CrO3CH3COOH. Ponadto przeprowadzono próbę jednoczesnej interkalacji dwóch interkalatów CrO3 oraz ZnCl2 celem otrzymania układu multiinterkalacyjnego. Aby stwierdzić czy zaszedł proces interkalacji CrO3 oraz ZnCl2 w grafit, produkt reakcji był badany metodą cyklicznej woltamperometrii w 95 % H2SO4. Na podstawie otrzymanych krzywych woltamperometrycznych stwierdzono obecność obu interkalatów (CrO3 oraz ZnCL2 w matrycy grafitowej. Ponadto, w wyniku anodowego utleniania CrOI3ZnCI2-IZG w 95% H2SO4 otrzymano układ poczwórny CrO3/ZnCl2H2SO4- grafit.

8

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

63%

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

Materials Science Poland

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2006

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tom 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.

9

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

63%

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

Materials Science Poland

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2006

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tom 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.

10

Study of methylene blue adsorption by modified kaolinite by dimethyl sulfoxide

63%

Lellou S. , Kadi S. , Guemou L. , Schott J. , Benhebal H.

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2020

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tom 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.

11

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

44%

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

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tom 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.