Wyniki wyszukiwania - BazTech

1

Effect of low-temperature plasma treatment on rubber properties

Ďurišová Silvia, Pajtášová Mariana, Ondrušová Darina, Janík Róbert, Mičicová Zuzana, Dubec Andrej, Pagáčová Jana, Šulcová Jana, Božeková Slavomíra, Vavro Jan, Klepka Tomasz

Polimery

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2024

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Vol. 69, nr 4

245--253

EN

The effect of the distance (0.5 and 5 mm) and exposure time (10 and 30 s) of the atmospheric plasma on the structure and surface properties (contact angle, adhesion) of unvulcanized rubber was examined. FT-IR and SEM were used to assess the structure. After plasma treatment, a higher intensity of the OH and COO- bands was observed, while the intensity of the bands from methylene groups decreased. SEM showed that plasma significantly reduces the size and number of agglomerates, resulting in a more uniform structure. The plasma distance has a significant effect on the surface properties of the rubber, with a better effect achieved at a smaller distance (0.5 mm). In this case, the rubber character changed from hydrophobic to hydrophilic, which is related to the introduction of oxygen species. A greater plasma distance (5 mm), regardless of the exposure time, resulted in a lower adhesion force. The exposure time had no significant effect on the tested rubber properties.

PL

Zbadano wpływ odległości (0,5 i 5 mm) oraz czasu ekspozycji (10 i 30 s) plazmy atmosferycznej na strukturę i właściwości powierzchniowe (kąt zwilżania, adhezja) niewulkanizowanej gumy. Do oceny struktury stosowano FT-IR i SEM. Po obróbce plazmą zaobserwowano większą intensywność pasm pochodzących od grup OH i COO-, natomiast intensywność pasm pochodzących od grup metylenowych zmniejszyła się. Metodą SEM wykazano, że plazma znacząco zmniejsza wielkość i liczbę aglomeratów, czego efektem jest bardziej jednorodna struktura. Odległość plazmy ma istotny wpływ na właściwości powierzchniowe gumy, przy czym lepszy efekt uzyskano przy mniejszej odległości (0,5 mm). W tym przypadku charakter gumy zmienił się z hydrofobowego na hydrofilowy, co jest związane z wprowadzeniem ugrupowań tlenowych. Większa odległość próbki od plazmy (5 mm), niezależnie od czasu ekspozycji, skutkowała mniejszą siłą adhezji. Czas ekspozycji nie miał istotnego wpływu na badane właściwości gumy.

2

Assessment of the quality of pharmaceutical packaging in the light of the requirements of the European Pharmacopoeia

Sieczyńska Katarzyna, Lasoń-Rydell Magdalena, Krępska Małgorzata

Technologia i Jakość Wyrobów

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2022

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R. 67

90--105

EN

The article presents the results of the analysis of metal contents in selected plastic products used for the production of containers which are divided into polyolefins, polyethylene, polypropylene, poly(ethylene terephthalate). This work includes the sample preparation and testing by inductively coupled plasma atomic emission spectrometry (ICP-OES) and FT-IR spectroscopy (ALPHA II). All tested packaging met the requirements of the European Pharmacopoeia (Ph. Eur.) in the context of heavy metals content. The spectra of the tested materials showed peaks at those mentioned in Ph. Eur. wavenumber for a given sample. The spectrum obtained is identical to that obtained with the material selected for the type sample. This study showed that packaging for medicinal products can be approved for use in the European Union.

PL

W artykule przedstawiono wyniki analizy zawartości metali w wybranych wyrobach z tworzyw sztucznych, stosowanych do produkcji pojemników - poliolefin, do których zalicza się m. in. polietylen, polipropylen, poli(tereftalan etylenu). W pracy uwzględniono etap przygotowania i badania próbek metodą atomowej spektrometrii emisyjnej z plazmą wzbudzoną indukcyjnie ICP-OES oraz spektroskopii podczerwieni FT-IR (ALPHA II). Wszystkie badane opakowania spełniły wymagania określone w Farmakopei Europejskiej (Ph. Eur.) w kontekście zawartości metali ciężkich i analizy tożsamości A. Widma badanych tworzyw wykazują maksima przy wymienionych w Ph. Eur. liczbach falowych dla danej próbki i są identyczne z widmem otrzymanym dla tworzywa wybranego na próbkę standardową. Badania wykazały, że opakowania do produktów leczniczych mogą zostać dopuszczone do zastosowania ich na terenie Unii Europejskiej.

3

Chemical characterization and biochemical activity of polysaccharides isolated from Egyptian Ulva fasciata Delile

Moawad Madelyn N., El-Sayed Abeer A.M., Abd El Latif Hala H., El-Naggar Naglaa A., El-Din Nihal G. Shams, Tadros Hermine R.Z.

Oceanologia

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2022

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No. 64 (1)

117--130

EN

This study gives updated information on the isolation of ulvan from green alga Ulva fasciata Delile in Egypt through isolation and chemical characterization of sulfate polysaccharides by two sequential extraction steps using different solvents; distilled water, HCl and Na2EDTA forming fraction I (F-I). Fraction II (F-II) was obtained from remaining seaweeds using NaOH to give FDWNaOH, FHClNaOH, and FEDTANaOH. All products obtained were tested for their biological activities. The highest polysaccharides total extraction yield was 11.8% for water extract (F-I and F-II). The highest protein content was found in FEDTANaOH (2.44%). The highest sulfate content was recorded for F-I (HCl) (21.38%). Total carbohydrates range was 11.99–63.90% for F-I and 15.06–76.65% for F-II. Monosaccharides; galactose, rhamnose, and uronic acid were detected at all fractions, with concentrations varying from 0.11 to 1.34%, from 0.61 to 1.81% and from 11.06 to 19.30%, respectively. 1H NMR of F-II demonstrated the signals of ring and methyl protons of polysaccharide. The appearance of the stretching bands of the sulfate ester (C-O-S) and sulfate groups (S=O) in the FT-IR spectrum of FHClNaOH confirmed the presence of sulfated polysaccharides, typical of ulvan. The microbial species Vibrio damsela was the most susceptible to FDWNaOH, followed by Aeromonas hydrophila and Vibrio fluvialis with inhibition zones of 30, 22, 22 mm at 150 mg/ml, respectively. FDWNaOH was the most effective fraction having antifouling property. The highest antioxidant activity was observed for F-IHCl followed by FDWNaOH. At concentrations 25 and 50 mg/l, FEDTANaOH displayed the highest anti-inflammatory activity (94.0 and 91.40%, respectively).

4

PET/Cloisite®15A composite fibers – studies on the structure and the flame inhibition mechanism

Fabia Janusz, Gawłowski Andrzej, Rom Monika, Ślusarczyk Czesław, Biniaś Włodzimierz, Brzozowska-Stanuch Anna, Puchalski Michał

Polimery

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2020

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T. 65, nr 9

622--631

EN

The improvement of poly(ethylene terephthalate) (PET) fibers flame retardancy is usually achieved by using antipyrenes, which may be incorporated into polyester molecules during polycondensation or are physically mixed with polymer in the fiber formation process. In this article we present an alternative method to reduce the flammability of PET fibers and fabrics which is analogous to dyeing them with a dispersed dyes in a high temperature bath. We have tested this method many times using various modifiers so far. This time, we applied a commercial organophilized montmorillonite Cloisite®15A (C15A). In the presented work, using Limited Oxygen Index (LOI) flammability tests and the thermogravimetric analysis (TGA) method, the effectiveness of the modification used was demonstrated and its optimal variant was determined. Based on Fourier Transform-Infrared Spectroscopy (FT-IR) studies, the existence of interactions between PET macromolecules and the C15A modifier in the entire temperature range of the oxidative degradation was confirmed. Using the Wide-Angle X-ray Scattering (WAXS) and Small-Angle X-ray Scattering (SAXS) methods, the basic parameters of the nanostructure of the studied fibers were determined, and their nanocomposite nature was confirmed. The most important goal, which was successfully achieved, was to explain the mechanism of flame inhibition by the applied modifier C15A.

PL

Poprawę właściwości palnych włókien poli(tereftalanu etylenu) (PET) można uzyskać w wyniku zastosowania uniepalniaczy, które mogą być wprowadzane do mieszaniny reakcyjnej podczas polikondensacji poliestru lub fizycznie mieszane z polimerem w procesie tworzenia włókien. W niniejszym artykule przedstawiono alternatywną metodę zmniejszania palności włókien i wyrobów tekstylnych z PET, analogiczną do procesu ich barwienia rozproszonymi barwnikami w kąpieli wysokotemperaturowej. Metodę tę testowaliśmy już wielokrotnie przy użyciu różnych modyfikatorów. Tym razem zastosowaliśmy handlowo dostępny organofilizowany montmorylonit Cloisite®15A (C15A). Za pomocą testów palności (określano wartość LOI – wskaźnika tlenowego) oraz analizy termograwimetrycznej (TGA) wykazano skuteczność zastosowanej modyfikacji i określono jej optymalny wariant. Na podstawie badań spektroskopowych FT-IR (spektroskopia w podczerwieni z transformacją Fouriera) potwierdzono występowanie oddziaływań między makrocząsteczkami PET i modyfikatora C15A w całym zakresie temperatury, obejmującym proces degradacji oksydacyjnej. Metodami szeroko i mało kątowej dyfrakcji rentgenowskiej (WAXS i SAXS) określono podstawowe parametry nanostruktury badanych włókien oraz potwierdzono ich nanokompozytowy charakter. Wyjaśniono także mechanizm inhibitowania płomienia przez zastosowany modyfikator C15A.

5

Impact assessment of farm tractor engine fuel injector damage on engine oil properties

Gołębiowski Wojciech, Zając Grzegorz

Agricultural Engineering

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2020

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Vol. 24, No. 2

65--75

EN

It is justified that the problems related to changes in physico-chemical properties, concentration of trace elements in lubricating oil and the impact of these changes and their dynamics on vehicle structural elements should be considered in detail. It is important that empirical data, theoretical relationships and test results should be taken into account. The paper presents research results of the selected physico-chemical parameters and the content of metals in samples of the used engine oil. The samples were collected both after the fuel system failure and during the operation of the farm tractor according to the date of changing engine oil assumed by the producer. An instrumental chemical analysis method HDXRF was used to determine chang-es of the content of trace elements Fe, Sn, Cu, Pb, P, Zn, Ca in engine oil. Additionally, changes in physico-chemical properties were determined with the use of FT-IR spectrometry. Courses of these changes were analysed on account of their impact on the utility properties of the engine oil.

PL

Uzasadnione jest, aby problemy związane ze zmianami właściwości fizykochemicznych, koncentracją pierwiastków śladowych w oleju smarowym oraz wpływu tych zmian na elementy konstrukcyjne pojazdu i ich dynamikę były rozpatrywane szczegółowo, biorąc pod uwagę dane empiryczne, zależności teoretyczne i wyniki badań. W pracy przedstawiono wyniki badań wybranych parametrów fizykochemicznych oraz zawartości metali w próbkach zużytego oleju silnikowego. Próbki pobierano zarówno po awarii układu paliwowego jak i podczas obsługi eksploatacyjnej ciągnika rolniczego zgodnie z założoną przez producenta datą wymiany oleju silnikowego. Metodą instrumentalnej analizy chemicznej HDXRF oznaczono w oleju silnikowym zmiany zawartości pierwiastków śladowych Fe, Sn, Cu, Pb, P, Zn, Ca. Dodatkowo określono zmiany właściwości fizykochemicznych za pomocą spektrometrii FT-IR. Przebiegi tych zmian przeanalizowano pod względem ich wpływu na właściwości użytkowe oleju.

6

Właściwości fizykochemiczne i funkcjonalne biokompozytów polimerowych

Wiśniewska-Wrona Maria, El Fray Mirosława

Polimery

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2019

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T. 64, nr 1

23--33

PL

Otrzymano błony biokompozytowe wytworzone na bazie chitozanu (Chit) i alginianu sodu (Alg) z udziałem substancji leczniczych o działaniu przeciwzapalnym (siarczan cynku) i przeciwbakteryjnym (sulfanilamid). Metodami spektrofotometrii w podczerwieni (FT-IR), magnetycznego rezonansu jądrowego (NMR) oraz różnicowej kalorymetrii skaningowej (DSC) oceniono wpływ zawartości chitozanu i alginianu na budowę chemiczną i temperaturę przemian fazowych biokompozytów. Analiza termiczna wykazała, że dodatek substancji leczniczych do materiałów biokompozytowych wpływa zarówno na obniżenie ich temperatury topnienia, jak i na zmniejszenie entalpii związanej z tą przemianą.

EN

Biocomposite films based on chitosan (Chit) and sodium alginate (Alg) and containing anti-inflammatory (zinc sulfate) and antimicrobial (sulfanilamide) pharmaceutical ingredients were prepared. The effects of variable chitosan and alginate contents on the chemical structure and phase transition temperatures of biocomposites were studied using infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC). Thermal analysis showed that the addition of pharmaceuticals decreased the melting temperature and melting enthalpy of polymer biocomposites.

7

Structural optical and electrical characterization of nanoparticle B doped ZnS films

Hurma Tulay

Materials Science Poland

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2019

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Vol. 37, No. 4

599--606

EN

Structural, morphological, optical and electrical characteristics of zinc sulfide (ZnS) and boron doped zinc sulfide (ZnS:B) films deposited on glass substrates by ultrasonic spray pyrolysis (USP) method and heated up to 350±5 °C were studied. B doping at various concentrations did not change the crystal structure of the ZnS film and it also did not cause any significant change in the size of crystallites. Maximum transmittance values of the B doped ZnS films increased parallel to doping rate. Transmittance edges showed shifting towards smaller wavelengths due to the effect of B doping. B doping increased optical band gap values. Scanning electron microscopy (SEM) images of the film surfaces showed that B doping did not cause any significant change in grain sizes of the films. Presence of all expected elements in the films including Zn, S and B was confirmed through Energy Dispersive Spectrometry (EDS) analysis. Significant peaks of foreign phases on the film surfaces were observed through Fourier Transform Infrared (FT-IR) spectroscopy. The electrical resistivity values of the films were calculated by means of current-voltage characteristics.

8

Surface characterization and froth flotation of fergusonite from Abu Dob pegmatite using a combination of anionic and nonionic collectors

Fawzy M. M.

Physicochemical Problems of Mineral Processing

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2018

|

Vol. 54, iss. 3

677--687

EN

The performance of the mixed anionic (sodium oleate) / nonionic (sorbitan monooleate) collectors on fergusonite flotation and separation from silicate gangue minerals was investigated using the flotation tests. The surface characterization of fergusonite before and after the treatment with the mixed collectors was determined using the zeta-potential measurements and FT-IR analyses. The results obtained from this study showed that the flotation recovery of fergusonite using sodium oleate enhanced in the presence of sorbitan monooleate, and the optimum floatability was achieved at pH 5 using 1 Kg/Mg blended collectors of sodium oleate and sorbitan monooleate as by a ratio 1:1 and methyl isobutyl carbinol (MIBC) as a frother. It was also found that the addition of sodium metasilicate to citric acid as a depressant showed a high affinity for silicate gangue minerals and weak affinity for fergusonite. The zeta-potential and FT-IR measurements of fergusonite after the treatment with the mixed collectors indicated a strong adsorption of these molecules on the particle surface due to chemisorptions. Additionally, The SEM analysis of high grade froth and its corresponding tailing product showed that the fergusonite mineral mostly concentrated in the froth, while the gangue silicate minerals relatively concentrated in the tailing. Finally, synergistic interaction between the anionic and nonionic surfactants was observed during adsorption on fergusonite and was succeeded for separation from its gangue silicate minerals.

9

Synthesis of NiO nanoparticles by sol-gel technique

Kayani Z. N., Butt M. Z., Riaz S., Naseem S.

Materials Science Poland

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2018

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Vol. 36, No. 4

547--552

EN

NiO nanoparticles were fabricated by sol-gel route using ammonium hydroxide and nickel nitrate as precursors. The NiO nanoparticles were calcinated at 400 °C and 1000 °C. The nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), thermogravimetry analysis/differential thermal analysis (TGA/DTA). The structural properties were evaluated by X-ray diffraction (XRD). XRD confirmed the formation of well-crystallized and high purity NiO phase. The XRD showed that the peaks were sharpened and the crystallite size increased as the calcination temperature increased. The average crystallite size ranged from 12 nm to 20 nm, when calcined at temperatures 400 °C and 1000 °C, respectively. Fourier transform infrared spectroscopy (FT-IR) revealed the chemical composition and confirmed the formation of NiO nanoparticles. The nanoparticles showed paramagnetic behavior.

10

Structural, non-linear optical and dielectric properties of LPAHCl-manganese sulphate and cadmium chloride co-crystals

Selvarani K., Mahalakshmi R., Thanuja B.

Materials Science Poland

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2018

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Vol. 36, No. 1

7--13

EN

Co-crystals of L-phenylalanine hydrochloride (LPAHCl) were grown by slow evaporation technique in the presence of manganese sulphate and cadmium chloride. Crystallinity of the grown crystals was confirmed by single crystal X-ray diffraction. Optical transmission spectra showed very high transmittance in the entire visible region. The cut-off wavelength was observed at 250 nm for both the crystals. The optical band gap energy was found to be 4.37 eV and 4.31 eV for the grown co-crystals of LPAHCl with MnSO4 and CdCl2, respectively. The second harmonic generation of the grown crystals was confirmed by Kurtz and Perry powder SHG method and compared with KDP. The frequency dependent dielectric properties of the co-crystals were studied at different temperatures.

11

Preparation and characterization of PEO-based composite gel-polymer electrolytes complexed with lithium trifluoro methane sulfonate

Nagajothi A. J., Kannan R., Rajashabala S.

Materials Science Poland

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2018

|

Vol. 36, No. 2

185--192

EN

Chitosan has been successfully incorporated as a filler in a polyethylene oxide (PEO) and lithium trifluoromethanesulfonate (LiCF3SO3) matrix with a combination of plasticizers, namely 1,3-dioxolane (DIOX) and tetraethylene glycol dimethylether (TEGDME). The composite gel-polymer electrolyte (CGPE) membranes were prepared by solution casting technique in an argon atmosphere. The prepared membranes were subjected to SEM, TG/DTA and FT-IR analyses. A Li/CGPE/Li symmetric cell was assembled and the variation of interfacial resistance was measured as a function of time. The lithium transference number (Li+t) was measured and the value was calculated as 0.6 which is sufficient for battery applications. The electrochemical stability window of the sample was studied by linear sweep voltammetry and the polymer electrolyte was found to be stable up to 5.2 V.

12

Electrical characteristics of PVA-PANI-ZnS nanocomposite film synthesized by gamma irradiation method

Bahrami A., Behzad K., Faraji N., Kharazmi A.

Materials Science Poland

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2018

|

Vol. 36, No. 1

102--106

EN

This work presents the synthesis of PANI-PVA-ZnS nanocomposite films by gamma irradiation approach. The samples were irradiated with different doses ranging from 10 kGy to 40 kGy. Subsequently, structural, morphological, optical and electrical characteristics of the samples were investigated. Fourier transform infrared (FT-IR) spectroscopy was employed to study the chemical structure of the samples. Field emission scanning electron microscopy (FE-SEM) was used to investigate the morphology of nanocomposites. The electronic absorption characteristics of the samples were measured by means of UV-Vis spectroscopy. The AC and DC electrical behaviors of the samples were characterized using LCR meter in the frequency range of 20 Hz to 1 MHz. The impedance values of the samples were extracted from Cole-Cole plots and consequently DC conductivity was calculated.

13

Definition of oil change intervals based on the analysis of selected physicochemical properties of used engine oils

Gołębiowski W., Wolak A., Zając G.

Combustion Engines

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2018

|

R. 57, nr 1

44--50

EN

The paper presents the results of a thorough analysis of selected physicochemical parameters of engine oils at the end of their useful life, based on the oil change intervals assumed by vehicle users. Twelve samples of used Castrol Edge 5W/30 synthetic oil and five samples of used Castrol Magnatec 10W/40 semi-synthetic oil were tested. The Eralytics's ERASPEC OIL device was used for the assessment of the following parameters: degree of oxidation, degree of nitration, degree of sulfonation, water content, glycol content, total base number (TBN), total acid number (TAN) and kinematic viscosity at 40°C and 100°C. The research was conducted on the basis of the ASTM E2412-10 standard. The results regarding the parameter limit exceedances have also been presented in the paper. For both synthetic and semi-synthetic oils, the exceedance of kinematic viscosity measured at 40°C was particularly striking. In fourteen samples (out of seventeen tested), at least one exceedance of the limit value (out of nine analyzed) has been observed.

14

Wykorzystanie przenośnego spektrometru FT-IR do określania półilościowego składu mineralogicznego skał zbiornikowych

Orzechowski M., Zagórska U., Hryniewicka K.

Nafta-Gaz

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2017

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R. 73, nr 5

295--301

PL

Analiza półilościowa składu mineralogicznego skał przy pomocy przenośnego spektrometru FT-IR jest metodą szybką i może stanowić ciekawą alternatywę dla innych metod analitycznych, takich jak XRD i XRF. Modele stworzone za pomocą algorytmu Beera będące podstawą do opracowania metodyki do analizy półilościowej dają bardzo dobre rezultaty, charakteryzując się wysokim współczynnikiem determinacji R2 dla widm podczerwonych oraz metod XRD i XRF. Przenośny spektrometr FT-IR może być z powodzeniem użyty zarówno w pomiarach laboratoryjnych, jak i terenowych. Metoda FT-IR może umożliwić szybką ocenę litologiczną przewiercanych warstw oraz jest pomocna przy wyborze prób do dalszych badań laboratoryjnych. W niniejszym artykule przedstawiono wstępne wyniki analizy półilościowej składu mineralogicznego skał zbiornikowych opartej na korelacji widm FTIR z wynikami analiz XRF i XRD.

EN

Semi-quantitative analysis of mineralogical composition of reservoir rocks with the use of portable FT-IR spectrometer is a quick analytical method and might be an interesting alternative to other methods such as XRD and XRF. Models created using Beer’s algorithm being the basis of methodology for semi-quantitative analysis, have given very good results with a high R2 determination coefficient, for infrared spectra and methods such as XRD and XRF. Portable FT-IR spectrometer can be successfully used for laboratory analyses as well as field measurements. The opportunity to analyze the mineralogical composition of rocks allows for quick lithological assessment of drilled layers and helps during sampling for further laboratory testing. This article shows preliminary results of semi-quantitative analyses of mineralogical composition of reservoir rocks based on correlations of infrared spectra with XRF and XRD results.

15

Synthesis, growth and characterization of organic crystal triphenylmethane p-nitroaniline: a nonlinear optical crystal

Bhuvaneswari G., Prasad L. G., Prabhavathi N.

Materials Science Poland

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2017

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Vol. 35, No. 3

667--672

EN

A triphenylmethane-4-nitroaniline salt has been synthesized and the crystals have been grown by using slow evaporation solution growth technique. The grown single crystal was investigated by recording the powder XRD, FT-IR spectrum, UV-Vis spectrum, Vickers microhardness test, dielectric measurements and powder SHG. The growth of crystal was confirmed by analyzing the XRD pattern and it was stated that the grown material crystallized in triclinic system. Vibrational peaks of the functional groups existing in the compound were identified. Vickers microhardness studies were carried to measure the mechanical strength. In order to identify the phase transition temperature, the dielectric studies were carried out at different temperatures. Dielectric constant, dielectric loss and impedance of the crystal were monitored with respect to the frequency of electric field.

16

Studies on rheological, structural, optical, electrical and surface properties of LiMn2O4 thin films by varied spin rates

Balakrishnan T., Subramanian N. S., Kathalingam A.

Materials Science Poland

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2017

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Vol. 35, No. 3

626--631

EN

LiMn2O4 thin films prepared by cost-effective spin coating method using optimized coating conditions are reported. Spin rate was varied and spin rate dependent properties were studied. Prepared films were characterized for their structural, morphological and optical properties. X-ray diffraction study of LiMn2O4 thin films confirmed the cubic spinel structure with the preferred orientation along (1 1 1) plane. Optical absorption studies showed band gap energy of 3.02 eV for the grown LiMn2O4 films. FT-IR bands assigned to asymmetric stretching modes of MnO6 group were located around 623 cm−1 and 514 cm−1 for the LiMn2O4 thin films. The weak band observed at 437 cm−1 was attributed to the LiO4 tetrahedra. The films showed high conductivity value 0.79 S/cm indicating the generation of effective network of the film for enhanced charge transport. AFM micrographs of the LiMn2O4 films deposited at 3000 rpm and 3500 rpm showed uniform distribution of fine grains throughout the surface without any dark pits, pinholes and cracks.

17

Structural and luminescent properties of Fe3+ doped PVA capped CdTe nanoparticles

Ravindranadh K., Rao M. C.

Materials Science Poland

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2017

|

Vol. 35, No. 2

390--397

EN

During recent decades, magnetic and semiconductor nanoparticles have attracted significant attention of scientists in various fields of engineering, physics, chemistry, biology and medicine. Fe3+ doped PVA capped CdTe nanoparticles were prepared by co-precipitation method and characterized by powder X-ray diffraction, SEM, TEM, FT-IR, optical, EPR and PL techniques to collect the information about the crystal structure, coordination/local site symmetry of doped Fe3+ ions in the host lattice and the luminescent properties of prepared sample. Powder XRD data revealed that the crystal structure belongs to a cubic system and its lattice cell parameters were evaluated. The average crystallite size was estimated to be 8 nm. The morphology of prepared samples was analyzed by using SEM and TEM investigations. Functional groups of the prepared sample were observed in FT-IR spectra. Optical absorption and EPR studies have shown that on doping, Fe3+ ions enter the host lattice in octahedral site symmetry. PL studies of Fe3+ doped PVA capped CdTe nanoparticles revealed UV and blue emission bands. CIE chromaticity coordinates were also calculated from the emission spectrum of Fe3+ doped PVA capped CdTe nanoparticles.

18

Influence of organic dopants (L-alanine and L-arginine) on structural, spectroscopic and thermal properties of ammonium dihydrogen phosphate crystal

Parikh K. D., Joshi J. H., Joshi M. J.

Materials Science Poland

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2017

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Vol. 35, No. 3

632--638

EN

Ammonium dihydrogen phosphate is a popular nonlinear optical crystal used for second harmonic generation efficiency improvement in pump lasers. Due to molecular chirality and zwitterionic structure, amino acids are used to enhance various properties of ADP crystal. The single crystals of ammonium dihydrogen phosphate (ADP) added with different concentrations (0.3 wt.%, 0.4 wt.% and 0.5 wt.%) of amino acids (L-alanine and L-arginine) impurities were grown using slow evaporation solution growth (SESG) technique at room temperature. To study the structural properties, powder XRD study was carried out which revealed that all the grown crystals have tetragonal structural symmetry. The presence of various functional groups was confirmed using FT-IR spectroscopy. The thermal spectra (TGA/DTA/DSC) were recorded for all grown samples to determine their decomposition. Also kinetic and thermodynamic parameters were determined from the thermal study.

19

Effect of magnesium substitution on structural and dielectric properties of LiNiPO4

Anand K., Ramamurthy B., Veeraiah V., Babu K. V.

Materials Science Poland

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2017

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Vol. 35, No. 1

66--80

EN

The aim of this paper is to study the effect of Mg2+ doping in place of Ni in LiNiPO4 compounds synthesized by solid state reaction method. As Mg is a relatively light and cheap, and is expected to stabilize the structure, it has been considered as a substituent for Ni. The structural and conductivity studies of the substituted phases are discussed in comparison with LiNiPO4. In this study, we have proposed cation-substituted compounds, LiNi1–xMgxPO4 (x = 0, 0.05, 0.1 and 0.15) where a part of the divalent state of Ni2+ is replaced with the corresponding amount of Mg2+ and where the charge compensation is maintained by lithium deficiency. It is possible to obtain the mentioned compounds because the pristine LiNiPO4 compound is stable in ambient atmosphere, which differs considerably from the LiCoPO4 compound.

20

Physicochemical Characterization Of The Multiuse Medical Textiles In Surgery And As Packaging Material In Medical Sterilization

Rogina-Car B., Flincec Grgac S., Katovic D.

Autex Research Journal

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2017

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Vol. 17, no. 3

206--212

EN

This work investigates changes in the physicochemical properties of dry multiuse medical textiles used in surgery and as packaging material in sterilization after 0, 1, 10, 20, 30, and 50 washing and sterilization cycles in real hospital conditions of the Clinical-Hospital Centre in Zagreb. Scanning electronic microscope (SEM) was used to perform morphological characterization. Physicochemical characterization and the resulting changes in the medical textiles were monitored using Fourier transform infrared (FT-IR) spectrometer. The change in the mass of the medical textiles as a results of temperature was determined by thermogravimetric (TG) analysis. Furthermore, structural characteristics based on the changes that resulted during the washing and sterilization processes are provided. The conclusion of the conducted research on the changes in the properties of multiuse medical textiles (Cotton/PES, Tencel®, and three-layer PES/PU/PES textile laminate) in real hospital conditions is that the medical textiles do manage to preserve properties after continuous use and it is safe to use them up to 50 washing and sterilization cycles.