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1

Nowe materiały funkcjonalne w konstrukcji czujników potencjometrycznych typu solid contact

Pietrzak Karolina, Wardak Cecylia

Wiadomości Chemiczne

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2025

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[Z] 79, 1-2

83--97

EN

Among all kinds of ion-selective electrodes, those with solid contact (SC-ISEs) are currently particularly popular. The elimination of the internal solution significantly improved electrical parameters and also enabled miniaturization, storage and transport of the sensors. However, not all active substances and electroactive materials can be successfully used to prepare these electrodes. The first of them must ensure, among other things, sufficient selectivity of the sensors towards the determined ion in the presence of other accompanying ions, while the second – good stability and reversibility of the potential. Therefore, new functional materials are constantly needed to obtain better and better potentiometric sensors, which can also be used in multi-sensor platforms for comprehensive determination of ion content directly in the in situ environment. This article is devoted to the topic of new functional materials that can be used to improve the operation of potentiometric sensors and expand the scope of their applications. All described electrodes were constructed as part of scientific research conducted during the doctoral studies of the author. Their main goal was to develop new ion-selective electrodes with solid contact with good analytical parameters and sensitive to selected ions (NO3-, Cl–, K+, Cu2+, UO22+), using new ionophores or electroactive materials for their construction. Many different sensors were constructed and tested, the design of which differed, among others, in the material of the internal electrode, the composition of the ion-selective membrane (qualitative and quantitative), and the type and method of using the solid contact material (as an intermediate layer or an additional component of the membrane). New materials were synthesized, their properties were tested using many different analytical methods and then used to prepare ion-selective electrodes. The values of the most important analytical parameters were determined for the obtained sensors and, on their basis, the influence of individual electrode modifications on their operation was determined. Using some of the obtained electrodes, the content of selected ions in natural samples was also analyzed, confirming that they can be used in practical analysis.

2

Rola opakowań w zachowaniu jakości żywności

Markowska Joanna

Przemysł Spożywczy

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2025

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T. 79, nr 3

40--47

PL

Branża opakowań to jedna z najprężniej rozwijających się gałęzi gospodarek światowych, o wysokim potencjale innowacyjnym. Wzajemne oddziaływanie czynników technologicznych, środowiskowych i wymagań konsumenckich zwiększyło rolę opakowań w utrzymaniu i poprawie bezpieczeństwa i jakości żywności, przedłużaniu okresu jej przydatności do spożycia i promowaniu atrakcyjności rynkowej. Biorąc pod uwagę złożoność funkcji opakowań do żywności, konieczna jest ciągła ocena ich bezpieczeństwa i skuteczności. Niniejszy artykuł zawiera przegląd wybranych rozwiązań funkcjonujących na rynku opakowań, ich zastosowań w celu zapewnienia optymalnej jakości i bezpieczeństwa zdrowotnego żywności.

EN

The packaging industry is one of the most rapidly growing branches of world economies, with a high potential for innovation. The interplay of technological factors, environmental factors and consumer demands has increased the role of packaging in maintaining and improving food safety and quality, extending shelf life and promoting market appeal. Given the complexity of food packaging functions, continuous evaluation of its safety and effectiveness is necessary. This article provides an overview of selected solutions operating in the packaging market, their applications to ensure optimal quality and health safety of food.

3

PVA/pectin/ZnO nanocomposites as antibacterial compounds for root canal treatment

Safaei Mohsen, Ahmadi Ramin, Salmani Mobarakeh Mohammad, Sharifi Roohollah, Ling Shing Wong, Rathi Shraddha, Amina, Afroz Shaista

Polimery

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2025

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Vol. 70, nr 5

331--339

EN

Structure and antibacterial activity of PVA/pectin/ZnO nanocomposites were investigated. The Taguchi method was used to select the optimal composition of the composites, considering the effect of PVA, pectin and ZnO on the biocidal properties. Various methods were used to characterize composites, including FT-IR, XRD, FESEM, EDS, TEM, elemental mapping, and TGA. The strong antibacterial properties of PVA/pectin/ZnO and complete inhibition of Enterococcus faecalis biofilm development were confirmed. The developed nanocomposites can be used in various fields as antimicrobial agents.

PL

Zbadano strukturę i aktywność przeciwbakteryjną nanokompozytów PVA/pektyna/ ZnO. Do wytypowania optymalnego składu kompozytów stosowano metodę Taguchi, uwzględniającą wpływ PVA, pektyny i ZnO na właściwości biobójcze. Do charakterystyki kompozytów stosowano różne metody, w tym FT-IR, XRD, FESEM, EDS, TEM, mapowanie pierwiastków i TGA. Potwierdzono silne właściwości przeciwbakteryjne PVA/pektyna/ZnO i całkowite zahamowanie rozwoju biofilmu Enterococcus faecalis. Opracowane nanokompozyty mogą być stosowane w różnych dziedzinach jako środki przeciwdrobnoustrojowe.

4

Investigating the Mechanical, Physical and Biological Properties of PMMA/TiO2 Composites with Nanoclay for Denture Applications

Ahmed Shaymaa Jumaah, Abdulridha Nazar J., Al-Obaidi Anwer J., Dalfi Hussein, Alomarah Amer

Engineering Transactions

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2025

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Vol. 73, iss. 1

29--43

EN

Prosthodontics uses permanent or removable dentures to replace missing teeth, with partial dentures made from cobalt chromium and full dentures from acrylic resin. This study presents Veracril self-curing acrylic, a material for hybrid artificial denture composites reinforced with montmorillonite (MMT) and titanium oxide (TiO2) particles. It is softer, lighter, and more stable than previous materials. Several experiments (mechanical, physical, and biological) have been carried out to examine the novel composite at various MMT and TiO2 weight ratios. The findings indicate that these additives significantly improve the mechanical properties of the matrix material, making it suitable for denture manufacturing. The addition of MMT as a filler enhances bonding between the matrix and additives. The additives' success in biological tests, including antibacterial activity and toxicity assessments, further supports their suitability for dental applications.

5

Microstructure and features of thermal behavior of polymer composites based on polylactic acid and carbon nanotubes

Lysenkov Eduard A., Lysenkova Iryna P.

Composites Theory and Practice

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2025

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R. 25, nr 2

123-131

EN

This study investigates the thermal behavior of biodegradable polylactide (PLA) modified with multi-walled car bon nanotubes (MWCNTs), conducted to determine the influence of the nanofiller and the prehistory on the structural and phase transformations in the polymer matrix. Experimental samples with different MWCNT contents were analyzed using differential scanning calorimetry to determine the glass transition temperatures, melting and crystallization features, as well as light microscopy methods to study the morphology. The obtained data made it possible to trace the dynamics of thermal transitions in nanocomposites considering the thermal prehistory and to identify trends in the formation of the crystalline structure depending on the MWCNT concentration. The results of the study indicate a complex interaction between the nanofiller and the polymer matrix, which is of significant importance for the development of new functional materials based on PLA with improved heat-resistant and mechanical properties.

6

AC dielectric properties of antimony-germanate-borate optical glass rods co-doped with silver nanoparticles

Boiko Oleksandr, Żmojda Jacek Mariusz, Kochanowicz Marcin, Ragiń Tomasz, Markiewicz Jakub, Markowski Krzysztof, Komarzyniec Grzegorz Karol

Archives of Electrical Engineering

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2025

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Vol. 74, nr 3

617--629

EN

The article presents the investigation of the AC dielectric properties of optical glass rods co-doped with Ag nanoparticles. The samples presented a molar composition of 20Sb 2O 3 –30GeO2 − (45 − 𝑥)H3BO3 –5Al2O3 –𝑥Ag and differed with Ag concentration 𝑥 in the range of 0.1 mol·%–0.6 mol·% as well as geometric dimensions. The rods have been prepared by the standard melt-quenching technique. An impedance spectroscopy in the measurement frequency range of 4 Hz–8 MHz at room temperature was used to determine the dielectric properties of rods. The paper shows frequency characteristics for impedance, phase shift angle, resistance, conductivity, dissipation factor, and both components of permittivity. The samples demonstrate high resistance (4.4 × 106 < 𝑅 < 2.0 × 1011 Ω) and mostly negative phase shift angle (0 < 𝜃 ≤ −90◦ ), which indicates the purely dielectric nature of the materials and their capacitive character. Introducing Ag NPs into the rod’s structure causes growth in the impedance of about 40–120%, amplifies the real part of the permittivity over fivefold, and increases the electrical conductivity from two to 4.5 times, depending on frequency 𝑓 . Resistance, conductivity, dissipation factor, and imaginary part of permittivity demonstrate two-step saddle-shape dependencies that reflect dielectric and conduction processes between non- or partly oxidized or fully oxidized Ag nanoparticles separated by a glass matrix. The saddle points are different for low and high frequency regions, the values of which are next to 500 Hz and 5 × 105 Hz, respectively, referring to two relaxation times in the interphase polarization process. Hopping conductivity has been proposed as the charge transfer mechanism in nanocomposite rods.

7

Synthesis and characterization of ceramic nanocomposite thin films SiO2-NiO for gas sensing

Ali Karrar Abdulameer, Al-Marzoki Kutaiba, Kareem Shaimaa J.

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 2

357--364

EN

This paper focuses on the preparation and characterization of thin films of SiO₂-NiO ceramic nanocomposite. These films were synthesized using the sol-gel method and deposited onto a quartz substrate through spin coating after hydrofluoric acid (HF) treatment for the glass substrate. The films synthesized using 70% SiO2-30% NiO mole ratio. Subsequently calcined at three different temperatures: 500°C, 700°C, and 900°C. The diagram of X-ray Diffraction (XRD) revealed the presence of large quantities of semiconductor NiO at 2θ= 37.4°, 62.8°, 75.5°, and 79.4° in addition to the presence of SiO2 in the structure, at 2θ=43.3°. The surface properties were studied using Scanning Electron Microscopy (SEM), and Fourier-Transform Infrared Spectroscopy (FTIR). The test results demonstrated structural and surface properties compatible with the requirements of sensing applications. FT-IR spectra shows absorption bands of Si-O-Si, Ni-O and O-H. This coating has shown good sensitivity and effective response toward ammonia gas under various measurement conditions, including temperatures ranging from 50 to 200°C. The film calcinated at 500 °C exhibited high sensitivity to NH3 gas at room temperature due to the presence of hydroxyl groups (OH-), which increased its ability to adsorb the gas. Additionally, the film calcinated at 900 °C showed even higher sensitivity compared to the film calcinated at 700 °C.

8

Three dimensional graphene in nanocomposites—structure-property scenarios and EMI/GAMMA shielding potential

Kausar Ayesha

Advances in Materials Science

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2025

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Vol. 25, nr 3(85)

104--126

EN

The present review article is planned to systematically unfold salient worth of three dimensional graphene based polymeric nanocomposites for radiation shielding (electromagnetic, nuclear, gamma, fast neutrons) purposes. As per literature reports so far, we discuss polymer/three dimensional graphene nanocomposites for variety of thermoplastic, thermoset, and conjugated matrices employed for related high end material designs. Accordingly, multifunctional hybrids of three dimensional graphene have been fabricated via facile/resourceful fabrication techniques, including solution processing, in situ method, melt technique, freeze drying, hydrothermal tactic, printing, foaming, and allied synthesis procedures. The ensuing three dimensional graphene based hybrids/nanomaterials have been analyzed for microstructural, structural integrity, electron/charge conduction, dielectric features, permittivity, radiation shielding effectiveness, shielding efficiency, and other features desirable for nuclear/gamma/electromagnetic radiation protection application. Besides, underlying mechanisms of radiation attenuation have also been argued, as per scientific surveys. It seems that performance of hierarchical graphene nanoassmblies relies upon nanoarchitectural adaptability, interfacial interactions/wettability, and structure-property synergies. Eventually, inimitable polymer/three dimensional graphene nanocomposites have been found promising to meet technological demands of radiation shielding in aeronautics, devices, defense, and nuclear power plant industries. Despite practical success of radiation shielding three dimensional graphene hybrids, in spite of pristine graphene, future deployment in related industrial modules seems to be connected to focused experimental/theoretical endeavors by field researchers to overcome underlying design/property/performance challenges.

9

Graphene quantum dots in conjugated and rubbery matrices - stipulations and physical/technical attributes

Kausar Ayesha

Advances in Materials Science

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2025

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Vol. 25, nr 1(83)

5--36

EN

This leading-edge overview delivers an all-inclusive knowledge on fundamentals, state-of-the-art, and technicalities of two important polymer categories filled with graphene quantum dots, namely conjugated polymer/graphene quantum dots and rubber/graphene quantum dots nanocomposites. According to the literature up till now, facile and efficient fabrication methods, like in situ polymerization, solution mixing, melt blending, etc. have been reported for these graphene quantum dots derived hybrids. The ensuing graphene quantum dots based nanocomposites were inspected for microstructural, electrical conductivity, charge transportation, thermal/mechanical resistance, fluorescence properties, and allied valuable physical features. Incidentally, we notice promising applications of inimitable categories of conjugated polymer/graphene quantum dots and rubber/graphene quantum dots hybrids for gas/molecular/piezoelectric sensors, supercapacitors, and biomedical areas. Nevertheless, due to limited reports on applied sides of graphene quantum dots filled conjugated/rubbery matrices, future research attempts seem indispensable to resolve challenges of optimized/controlled processing and also to unveil structure-property-performance links and synergistic mechanisms for developing next generation industrial level conjugated polymer/graphene quantum dots and rubber/graphene quantum dots nanocomposites.

10

Mechanical and thermal properties of rigid PVC and graphene nanocomposites obtained by melt-mixing

Wilczewski Sławomir, Skórczewska Katarzyna, Tomaszewska Jolanta, Lewandowski Krzysztof, Şentürk Ömer Faruk

Polimery

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2024

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Vol. 69, nr 2

86--91

EN

The effect of graphene (0.01, 0.1, 0.5 and 1 wt%) on the mechanical properties and thermal stability of rigid PVC was investigated. The morphology and thermal properties were analyzed by scanning electron microscopy (SEM) and thermogravimetric thermal analysis (TGA). Additionally, tensile properties, impact strength and hardness were determined. It was found that the addition of graphene can increase the impact strength and hardness and extend the thermal stability time of PVC.

PL

Zbadano wpływ grafenu (0,01; 0,1; 0,5 i 1% mas.) na właściwości mechaniczne i stabilność termiczną twardego PVC. Strukturę i właściwości termiczne analizowano za pomocą skaningowej mikroskopii elektronowej (SEM) i termograwimetrycznej analizy termicznej (TGA). Ponadto określono właściwości mechaniczne przy rozciąganiu, udarność i twardość. Stwierdzono, że dodatek grafenu może zwiększyć udarność i twardość oraz wydłużyć czas stabilności termicznej PVC.

11

Chitosan with the addition of zeolite and ZnO nanoparticles as a new antibacterial agent

Safaei Mohsen, Mobarakeh Mohammad Salmani, Mozaffari Hamid Reza, Wong Ling Shing, Fallahnia Nima

Polimery

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2024

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Vol. 69, nr 10

559--567

EN

Chitosan/zeolite/ZnO nanocomposites with different contents of components were obtained using the Taguchi method. Based on the conducted studies, optimal conditions for the synthesis of the nanocomposite (7.5 mg/mL chitosan, 0.2 mg/mL zeolite and 9 mg/mL ZnO) with the best antibacterial properties (no growth of S. mutans) were established. Spectroscopic, microscopic, thermal, and antibacterial methods were used to characterize the nanocomposite and its components in relation to S. mutans biofilm. The chitosan/zeolite/ZnO nanocomposite can be used as an effective antibacterial compound in various applications due to its structural and antibacterial properties.

PL

Metodą Taguchi otrzymano nanokompozyty chitozan/zeolit/ZnO o różnej zawartości chitozanu, zeolitu i ZnO. Na podstawie przeprowadzonych badań ustalono optymalne warunki syntezy nanokompozytu (7,5 mg/mL chitozanu, 0,2 mg/mL zeolitu i 9 mg/mL ZnO) o najlepszych właściwościach przeciwbakteryjnych (brak wzrostu bakterii S. mutans). Do scharakteryzowania nanokompozytu i jego składników w odniesieniu do biofilmu S. mutans zastosowano metody spektroskopowe, mikroskopowe, termiczne i przeciwbakteryjne. Nanokompozyt chitozan/zeolit/ZnO może być stosowany jako skuteczny związek antybakteryjny w różnych zastosowaniach ze względu na swoją strukturalne i właściwości antybakteryjne.

12

Biocompatibility of electrospun PVA-based nanocomposite with chemical vapor deposition-derived graphene monolayer

Sasmazel Hilal Turkoglu, Alazzawi Marwa, Sadhu Verra, Gozutok Melike

Polimery

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2024

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Vol. 69, nr 11-12

657--667

EN

The biocompatibility of electrospun PVA with monolayer graphene obtained by chemical vapor deposition (PVA/CVD-grown MLG) nanocomposite was investigated. The properties of PVA/ CVD-grown MLG nanocomposite were compared with those of electrospun PVA mat. Raman analysis confirmed the presence of graphene monolayer on PVA. Although no significant changes in tensile properties were observed, the electrical conductivity increased from 0.1 (PVA mat) to 0.4 μS/cm (PVA/ CVD-grown MLG). Thermal stability was also increased, as evidenced by the higher onset temperature and temperature of maximum decomposition rate determined by TGA. The contact angle decreased slightly, which resulted in higher PBS absorption and degradation of the nanocomposite. Water vapor transmission rate (WVTR) decreased from 40 (PVA mat) to 37 g/m2 h (PVA/CVD-grown MLG). Cell culture studies showed better cell viability, population, and growth in the case of PVA/CVD-grown MLG nanocomposite due to improved physical, chemical and mechanical properties.

PL

Zbadano biokompatybilność nanokompozytu elektroprzędzonego PVA i monowarstwowego grafenu otrzymanego metodą chemicznego osadzania z fazy gazowej. Właściwości nanokompozytu porównano z właściwościami elektroprzedzonej maty PVA. Analiza Ramana potwierdziła obecność monowarstwy grafenu na PVA. Pomimo, że nie stwierdzono istotnych zmian właściwości mechanicznych przy rozciąganiu, to przewodnictwo elektryczne wzrosło z 0,1 (mata PVA) do 0,4 μS/cm (nanokompozyt). Zwiększyła się również stabilność termiczna, o czym świadczy wyższa temperatura początku rozkładu i maksymalnej szybkości rozkładu oznaczona metodą TGA. Nieznacznie zmniejszył się kąt zwilżania, co skutkowało większą absorpcją PBS i degradacją nanokompozytu. WVTR zmniejszył się z 40 (mata PVA) do 37 g/m2•h (nanokompozyt). Ponadto ze względu na lepsze właściwości fizyczne, chemiczne i mechaniczne nanokompozytu uzyskano większą żywotność, populację i wzrost komórek.

13

Computer Simulations of Poisson’s Ratio of a Simple Periodic Model Structure of Cubic Symmetry : Comparison of Results Obtained by Different Methods

Wojciechowski Krzysztof W., Smardzewski Jerzy, Stręk Tomasz, Tretiakov Konstantin V.

Computational Methods in Science and Technology

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2024

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Vol. 30, No. 3-4

63--67

EN

Poisson’s ratio of a periodic model system, based on a cubic crystal with Lennard-Jones interactions, is studied in the direction of the 4-fold axis of the crystal. It is shown that results of atomistic Monte Carlo simulations agree well with results of continuous finite element simulations for systems as small as those built of supercells based on 6 × 6 × 6 unit cells.

14

Effect of TiC and BN nanoparticles on mechanical and microstructural characteristics of Al7085 hybrid nanocomposites

Garapati Prem Kumar, Dumpala Lingaraju, Rao Y Seetha Rama

Composites Theory and Practice

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2024

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R. 24, nr 1

57--64

EN

This study regards investigations of the mechanical properties of aluminum 7085/TiC/BN hybrid metal matrix nanocomposites (HMMNCs). The ultrasonic assisted stir casting (UASC) route was used to manufacture the Al7085 HMMNCs by varying the wt.% of titanium carbide (TiC) and boron nitride (BN) (0.0, 0.5, 1.0, 1.5, and 2.0). By means of scanning electron microscopy (SEM) it was observed that the nanoparticles are evenly distributed in the nanocomposites. Additionally, the EDS and XRD results indicate that there were no signs of oxide formations, secondary phases, or impurities in the nanocomposites. The yield tensile strength (YTS), ultimate tensile strength (UTS) and microhardness of the nanocomposites improved with increases in the wt.% of TiC and BN particles up to 1.5, and thereafter decreased. The % elongation of the nanocomposites was reduced and the density of the nanocomposites improved with the addition of TiC and BN nanoparticles.

15

Zinc and graphene oxide composites as new protective coatings for oil and gas pipes

Asghar M. Sajid Ali, Amir Muhammad, Hussain Umer, Sabri Mohammed M.

Polimery

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2023

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Vol. 68, nr 7-8

378--385

EN

A method was developed to obtain a durable coating consisting of zinc and graphene oxide (Zn-GO) in order to reduce the mechanical wear and tear rate of oil and gas pipelines made of steel. Graphene oxide was obtained from graphite by wet chemical oxidation (unmodified and modified Hummers’ method) using potassium permanganate and sulfuric acid. The process was carried out at various temperatures. The steel was covered with an ultrathin layer of Zn-GO using the electrophoretic deposition method. The GO particle size (< 90 nm) was confirmed by XRD and laser analysis. For GO particles obtained by the modified Hummers’ method, a significant correlation was observed in the scratch (R2 = 0.87) and the Vickers microhardness tests (R2 = 0.93), which indicates a lower wear rate of Zn-GO-coated steel.

PL

Opracowano metodę otrzymywania trwałej powłoki składającej się z cynku i tlenku grafenu (Zn-GO) w celu zmniejszenia zużycia mechanicznego rurociągów naftowo-gazowych wykonanych ze stali. Tlenek grafenu pozyskano z grafitu metodą mokrego utleniania chemicznego (niezmodyfikowana i zmodyfikowana metoda Hummersa) z użyciem nadmanganianu potasu i kwasu siarkowego. Proces prowadzono w różnej temperaturze. Stal powlekano ultra cienką warstwą Zn-GO techniką osadzania elektroforetycznego. Metodą XRD i analizą laserową potwierdzono wielkość cząstek GO (≤ 90 nm). Dla cząstek GO otrzymanych zmodyfikowaną metoda Hummersa zaobserwowano znaczącą korelację w teście zarysowania (R2 = 0.87) i mikrotwardości Vickersa (R2 = 0.93), co świadczy o mniejszym stopniu zużycia stali pokrytej powłoką Zn-GO.

16

The use of chitosan as an effective carrier of theophylline – an anti-asthmatic drug

Aziz Noor Firas, Hussein-Al-Ali Samer Hasan, Ghareeb Mowafaq Mohammed, Nashwan Nashwan Abdallah

Polimery

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2023

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Vol. 68, nr 3

157--168

EN

In order to solve the problem of frequent drug dosing and increase its effectiveness, theophylline (THP) was deposited on chitosan nanoparticles (CSNPs). THP-CSNPs nanocomposites with the composition of 50, 75, 100 or 150 mg of chitosan (CS) and 25, 50, 75, 100 or 200 mg of tripolyphosphate (TPP) at pH 4.0, 5.0, 6.0 and 6.5 were prepared, and a constant weight of THP of 100 mg. The nanocomposites were characterized by X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), and Fourier transform infrared spectroscopy (FTIR). The rate of drug release was also tested. The Minitab 18 program was used to analyze the results. The independent variables were the CS, TPP, and pH, while loading efficiency, zeta potential, and particle size were the dependent variables. The nanocomposites successfully transported and protected the drug, providing its sustained release.

PL

W celu rozwiązania problemu częstego dawkowania leku i zwiększenia jego efektywności teofilinę (THP) osadzono na nanocząstkach chitozanu (CSNPs). Przygotowano nanokompozyty THP-CSNPs o składzie 50, 75, 100 lub 150 mg chitozanu (CS) oraz 25, 50, 75, 100 lub 200 mg trójpolifosforanu (TPP) przy pH 4,0, 5,0, 6,0 i 6,5 oraz stałej masie THP wynoszącej 100 mg. Nanokompozyty charakteryzowano za pomocą dyfrakcji promieniowania rentgenowskiego (PXRD), skaningowej mikroskopii elektronowej z emisją polową (FE-SEM), spektroskopii w podczerwieni z transformacją Fouriera (FTIR). Zbadano również szybkość uwalniania leku. Do analizy wyników wykorzystano program Minitab 18. Niezależnymi zmiennymi były CS, TPP i pH, podczas gdy wydajność ładowania, potencjał zeta i wielkość cząstek były zmiennymi zależnymi. Nanokompozyty z powodzeniem transportowały i zabezpieczały lek, zapewniając jego przedłużone uwalnianie.

17

Synthesis of hydrogel nanocomposites and their application in removing dyes and impurities

Ebrahimi Rajabali, Taherkhani Mahboubeh

Polimery

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2023

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Vol. 68, nr 5

276--285

EN

Polyacrylate hydrogels containing starch, ZnSe and Fe3O4 nanoparticles were obtained. The polymerization process was carried out in an ultrasonic field. The structure (SEM, FTIR, XRD), swelling properties and the ability of hydrogels to adsorb dyes (methylene blue, methyl orange, methyl red and Eriochrome Black T) and heavy metals (Cu2+) from wastewater were investigated. Hydrogels containing AgCl nanoparticles were also obtained, which, due to their antibacterial properties, can be potentially used in medicine.

PL

Otrzymano hydrożele poliakrylanowe zawierające nanocząstki skrobi, ZnSe i Fe3O4. Proces polimeryzacji prowadzono w polu ultradźwiękowym. Zbadano strukturę (SEM, FTIR, XRD), właściwości pęczniejące oraz zdolność hydrożeli do adsorpcji barwników (błękit metylenowy, oranż metylowy, czerwień metylowa i czerń eriochromowa T) oraz metali ciężkich (Cu2+) ze ścieków. Otrzymano również hydrożele zawierające nanocząstki AgCl, które ze względu na właściwości antybakteryjne mogą znaleźć potencjale zastosowanie w medycynie.

18

Morphology and selected properties of NR/BR/CNT nanocomposites – effect of ethanol-assisted mixing

Zhang Juzheng, Gu Zheng, Meng Chao, Wang Jianfa, Sui Jinyong

Polimery

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2023

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Vol. 68, nr 5

251--258

EN

Carbon nanotubes (CNT) and ethanol-assisted mixing were used to obtain composites based on a mixture of natural rubber and butadiene rubber (NR/BR 80/20). The structure of the composites was determined by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Thermal aging tests were also carried out and the vulcanization process was characterized. SEM confirmed the homogeneous dispersion of CNTs in the polymer matrix. Improvements in tensile and tear strength as well as thermal stability were also achieved.

PL

Do otrzymywania kompozytów na bazie mieszaniny kauczuku naturalnego i butadienowego (NR/BR 80/20) zastosowano nanorurki węglowe (CNT) i mieszanie wspomagane etanolem. Strukturę kompozytów określono za pomocą spektroskopii w podczerwieni z transformacją Fouriera (FTIR) oraz skaningowej mikroskopii elektronowej (SEM). Przeprowadzono również badania starzenia termicznego oraz scharakteryzowano proces wulkanizacji. Metodą SEM potwierdzono jednorodną dyspersję CNT w osnowie polimerowej. Uzyskano również poprawę wytrzymałości na rozciąganie i rozdzieranie oraz stabilności termicznej.

19

The effect of mouthwashes on changes in the aesthetic properties of dental nanocomposite

Chladek Grzegorz, Tegnander T.

Journal of Achievements in Materials and Manufacturing Engineering

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2023

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Vol. 121, nr 1

131--140

EN

The paper aims to investigate the effect of various types of mouthwashes on changes in the colour of dental nanocomposite in studies simulating their long-term contact. The hypothesis was that the offered Mouthwashes are safe in terms of maintaining a high level of aesthetics of composite nanomaterials used for direct fillings. Design/methodology/approach The composite nanomaterial was subjected to simulated ageing in twelve different types of mouthwash with different chemical compositions and distilled water. Three exposure times were used, corresponding to two, four- and six-year periods of use. Colour measurements were carried out after each exposure time, and the colour change expressed by ΔE* and particular coordinates (ΔL*, Δa*, Δb*) were determined. The results were subjected to statistical analyses. Findings Most patients diagnosed with TMD experienced traumatic events in childhood, while no similar cases were reported in the control group. Significant asymmetry was also found in the TMD group. The gender of the patients did not influence the asymmetries. There was no correlation between the age of the patients and the asymmetry in patients with TMD. Still, the correlation occurred in the control group due to significant asymmetries for the youngest patients. The results were subjected to statistical analyses. Research limitations/implications The simulated exposure is a simplification compared to clinical conditions, where the contact of the material with the fluid is cyclical, and the material is exposed to many other destructive factors. Practical implications Mouthwashes are widely used chemotherapeutic agents, and composite materials are used in the oral cavity of most of the population. One of the basic advantages of dental composites is their high aesthetics, for which the possibility of obtaining the desired colour and its stability is a fundamental issue. Originality/value Research shows that mouthwashes cause discolouration, but they are acceptable. However, caution is recommended in the case of mouthwashes containing charcoal, which have not been analysed in this respect so far.

20

Influence of EDM process parameters of novel Al7010/B4C/BN hybrid metal matrix nanocomposite

Dirisenapu Gopichand, Salavaravu Laxmanaraju, Dumpala Lingaraju

Composites Theory and Practice

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2023

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R. 23, nr 4

191--196

EN

In this present research work, the electrical discharge machining (EDM) characteristics of an Al7010/2%B4C/2%BN (the reinforcement particles are taken as wt.%) hybrid metal matrix nanocomposite (HMMNC) are discussed. The effect of the EDM process variables like the discharge current (I), pulse on time (Pon), pulse off time (Poff) and gap voltage (Vg) on the response characteristics like the material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) are presented. The results revealed that the MRR, TWR, and SR grew with an increase in Ip and Pon. MRR, TWR, and SR increased with a rise in Poff up to 25 μs then declined. MRR, TWR, and SR decreased with an increment in gap voltage. The highest MRR was observed for a discharge current of 8 A, Pon of 60 μs, Poff of 25 μs and Vg of 30 V. SR and TWR were the smallest at Ip of 2 A, Pon of 15 μs, Poff of 55 μs and Vg of 60 V. The scanning electron microscope (SEM) micrographs of the machined surfaces revealed voids, craters and micro cracks.