TY - JOUR AU - Nguyen Huu Huong, Duyen AU - Muthu, Arjun AU - El-Ramady, Hassan AU - Daróczi, Lajos AU - Nagy, Lajos AU - Kéki, Sándor AU - Béni, Áron AU - Csarnovics, István AU - Prokisch, József TI - Optimization of Extraction Conditions to Synthesize Green Carbon Nanodots from Maillard Reaction JF - MATERIALS ADVANCES J2 - MATER ADV VL - 5 PY - 2024 SP - 3499 EP - 3505 PG - 7 SN - 2633-5409 DO - 10.1039/D4MA00037D UR - https://m2.mtmt.hu/api/publication/34720754 ID - 34720754 AB - Carbon nanodots (CNDs) are a class of nanoparticles with unique optical properties with broad applications in various fields. However, synthesizing CNDs with high fluorescence intensity and small size using green... LA - English DB - MTMT ER - TY - JOUR AU - Hatvani-Nagy, Alpár Ferencz AU - Hajdu, Viktória AU - Ilosvai, Mária Ágnes AU - Muránszky, Gábor AU - Sikora, Emőke AU - Kristály, Ferenc AU - Daróczi, Lajos AU - Viskolcz, Béla AU - Fiser, Béla AU - Vanyorek, László TI - Bentonite as eco-friendly natural mineral support for Pd/CoFe2O4 catalyst applied in toluene diamine synthesis JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 14 PY - 2024 IS - 1 PG - 9 SN - 2045-2322 DO - 10.1038/s41598-024-54792-5 UR - https://m2.mtmt.hu/api/publication/34656926 ID - 34656926 AB - Toluene diamine (TDA) is a major raw material in the polyurethane industry and thus, its production is highly important. TDA is obtained through the catalytic hydrogenation of 2,4-dinitrotoluene (2,4-DNT). In this study a special hydrogenation catalyst has been developed by decomposition cobalt ferrite nanoparticles onto a natural clay-oxide nanocomposite (bentonite) surface using a microwave-assisted solvothermal method. The catalyst particles were examined by TEM and X-ray diffraction. The palladium immobilized on the bentonite crystal surface was identified using an XRD and HRTEM device. The obtained catalyst possesses the advantageous property of being easily separable due to its magnetizability on a natural mineral support largely available and obtained through low carbon- and energy footprint methods. The catalyst demonstrated outstanding performance with a 2,4-DNT conversion rate exceeding 99% along with high yields and selectivity towards 2,4-TDA and all of this achieved within a short reaction time. Furthermore, the developed catalyst exhibited excellent stability, attributed to the strong interaction between the catalytically active metal and its support. Even after four cycles of reuse, the catalytic activity remained unaffected and the Pd content of the catalyst did not change, which indicates that the palladium component remained firmly attached to the magnetic support's surface. LA - English DB - MTMT ER - TY - CONF AU - Kocsis, Beatrix AU - Mi-Kyung, Lee AU - Jae-Hyuk, Yu AU - Nagy, Tibor AU - Daróczi, Lajos AU - Batta, Gyula Gábor (Ifj.) AU - Pócsi, István AU - Leiter, Éva Juliánna TI - Comprehensive functional analyses of the bzip transciption factors AtfA and AtfB in Aspergillus Nidulans T2 - 16th European Conference on Fungal Genetics: Programme & Abstracts PB - Universität Innsbruck C1 - Innsbruck PY - 2023 SP - 705 EP - 706 PG - 2 UR - https://m2.mtmt.hu/api/publication/34453415 ID - 34453415 LA - English DB - MTMT ER - TY - JOUR AU - Ilosvai, Mária Ágnes AU - Forgách, László AU - Stelczerné Kovács, Noémi AU - Heydari, Fatemeh AU - Szigeti, Krisztián AU - Máthé, Domokos AU - Kristály, Ferenc AU - Daróczi, Lajos AU - Kaleta, Zoltán AU - Viskolcz, Béla AU - Nagy, Miklós AU - Vanyorek, László TI - Development of Polymer-Encapsulated, Amine-Functionalized Zinc Ferrite Nanoparticles as MRI Contrast Agents JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 22 PG - 19 SN - 1661-6596 DO - 10.3390/ijms242216203 UR - https://m2.mtmt.hu/api/publication/34315952 ID - 34315952 AB - The need for stable and well-defined magnetic nanoparticles is constantly increasing in biomedical applications; however, their preparation remains challenging. We used two different solvothermal methods (12 h reflux and a 4 min microwave, MW) to synthesize amine-functionalized zinc ferrite (ZnFe2O4-NH2) superparamagnetic nanoparticles. The morphological features of the two ferrite samples were the same, but the average particle size was slightly larger in the case of MW activation: 47 ± 14 nm (Refl.) vs. 63 ± 20 nm (MW). Phase identification measurements confirmed the exclusive presence of zinc ferrite with virtually the same magnetic properties. The Refl. samples had a zeta potential of −23.8 ± 4.4 mV, in contrast to the +7.6 ± 6.8 mV measured for the MW sample. To overcome stability problems in the colloidal phase, the ferrite nanoparticles were embedded in polyvinylpyrrolidone and could be easily redispersed in water. Two PVP-coated zinc ferrite samples were administered (1 mg/mL ZnFe2O4) in X BalbC mice and were compared as contrast agents in magnetic resonance imaging (MRI). After determining the r1/r2 ratio, the samples were compared to other commercially available contrast agents. Consistent with other SPION nanoparticles, our sample exhibits a concentrated presence in the hepatic region of the animals, with comparable biodistribution and pharmacokinetics suspected. Moreover, a small dose of 1.3 mg/body weight kg was found to be sufficient for effective imaging. It should also be noted that no toxic side effects were observed, making ZnFe2O4-NH2 advantageous for pharmaceutical formulations. LA - English DB - MTMT ER - TY - CHAP AU - Harasztosi, Tamás AU - Bazsó, Tamás AU - Kiss, Rebeka Gyöngyi AU - Csernátony, Zoltán AU - Harasztosi, Petra AU - Daróczi, Lajos AU - Harasztosi, Lajos ED - IEEE, Staff TI - Development and application of a wireless, in body data acquisition system for observation of experimental rabbit’s bone healing T2 - 2023 46th International Spring Seminar on Electronics Technology (ISSE) PB - IEEE CY - Timisoara SN - 9798350334845 PY - 2023 SP - 1 EP - 4 PG - 4 DO - 10.1109/ISSE57496.2023.10168448 UR - https://m2.mtmt.hu/api/publication/34128116 ID - 34128116 LA - English DB - MTMT ER - TY - JOUR AU - Hajdu, Viktória AU - Prekob, Ádám AU - Muránszky, Gábor AU - Kristály, Ferenc AU - Daróczi, Lajos AU - Harasztosi, Lajos AU - Kaleta, Zoltán AU - Viskolcz, Béla AU - Nagy, Miklós AU - Vanyorek, László TI - Amine Functionalization Leads to Enhanced Performance for Nickel- and Cobalt-Ferrite-Supported Palladium Catalysts in Nitrobenzene Hydrogenation JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 17 PG - 14 SN - 1661-6596 DO - 10.3390/ijms241713347 UR - https://m2.mtmt.hu/api/publication/34117847 ID - 34117847 AB - Easy preparation, good yield and easy recovery are the key challenges in the development of industrial catalysts. To meet all these three criteria, we have prepared intelligent, magnetizable NiFe2O4- and CoFe2O4-supported palladium catalysts that can be easily and completely recovered from the reaction medium by magnetic separation. The fast and facile preparation was achieved by a solvothermal method followed by sonochemical-assisted decomposition of the palladium nanoparticles onto the surface of the magnetic nanoparticles. The metal–support interaction was enhanced by amine functionalization of the supports using monoethanolamine. The performance and stability of the non-functionalized and amine-functionalized NiFe2O4- and CoFe2O4-supported palladium catalysts were compared in the industrially important nitrobenzene hydrogenation reaction. All catalysts showed high catalytic activity during aniline synthesis; complete nitrobenzene conversion and high aniline yield (above 97 n/n%) and selectivity (above 98 n/n%) were achieved. However, during reuse tests, the activity of the non-functionalized catalysts decreased, as the palladium was leached from the surface of the support. On the other hand, in the case of their amine-functionalized counterparts, there was no decrease in activity, and a non-significant decrease in palladium content could be measured. Based on these results, it can be concluded that amine functionalization of transition metal ferrites may result in more effective catalysts due to the enhanced metal–carrier interaction between the support and the precious metal. LA - English DB - MTMT ER - TY - JOUR AU - Czifrák, Katalin AU - Lakatos, Csilla AU - Szabó, Gabriella AU - Vadkerti, Bence AU - Daróczi, Lajos AU - Zsuga, Miklós AU - Kéki, Sándor TI - Bisphenol A Diglycidyl Ether-Primary Amine Cooligomer-poly(ε-caprolactone) Networks: Synthesis and Characterization JF - POLYMERS J2 - POLYMERS-BASEL VL - 15 PY - 2023 IS - 13 SP - 1 EP - 15 PG - 15 SN - 2073-4360 DO - 10.3390/polym15132937 UR - https://m2.mtmt.hu/api/publication/34081525 ID - 34081525 AB - In this work, the preparation and systematic investigation of cross-linked polyurethane-epoxy (PU-EP) polymer systems are reported. The PU-EP polymers were prepared using a reaction of isocyanate (NCO)-terminated PU-prepolymer with diglycidyl ether of bisphenol A (DGEBA)-amine cooligomer. The oligomerization of DGEBA was carried out by adding furfurylamine (FA) or ethanolamine (EA), resulting in DGEBA-amine cooligomers. For the synthesis of NCO-terminated PU-prepolymer, poly(ε-caprolactone)diol (PCD) (Mn = 2 kg/mol) and 1,6-hexamethylene diisocyanate (HDI) were used. The cross-linking was achieved by adding DGEBA-amine cooligomer to PU-prepolymer, in which the obtained urethane bonds, due to the presence of free hydroxil groups in the activated DGEBA, served as netpoints. During cross-linking, ethanolamine provides an additional free hydroxyl group for the formation of a new urethane bond, while furfurylamine can serve as a thermoreversible coupling element (e.g., Diels–Alder adduct). The PU-EP networks were characterized using attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), dynamical mechanical analysis (DMA) and scanning electron microscopy (SEM). The DMA curves of some PU-EPs (depending on the compositions and the synthetic method) revealed a plateau-like region above the melting temperature (Tm) of PCD, confirming the presence of a cross-linked structure. This property resulted in a shape memory (SM) behavior for these samples, which can be fine-tuned in the presence of furfurylamine through the formation of additional thermoreversible bonds (e.g., Diels–Alder adduct). LA - English DB - MTMT ER - TY - JOUR AU - Kamel, Sarah M. AU - Daróczi, Lajos AU - Tóth, László Zoltán AU - Panchenko, Elena AU - Chumljakov, Yuriy I. AU - Mohareb, Nora Samy Sdky AU - Beke, Dezső TI - Acoustic emission and DSC investigations of anomalous stress-stain curves and burst like shape recovery of Ni49Fe18Ga27Co6 shape memory single crystals JF - INTERMETALLICS J2 - INTERMETALLICS VL - 159 PY - 2023 PG - 13 SN - 0966-9795 DO - 10.1016/j.intermet.2023.107932 UR - https://m2.mtmt.hu/api/publication/33786706 ID - 33786706 N1 - Department of Solid State Physics, Doctoral School of Physics, Faculty of Science and Technology, University of Debrecen, P. O. Box 400, Debrecen, H-4002, Hungary Physics Department, Faculty of Science Ain Shams University, Abbassia, Cairo, 11566, Egypt Siberian Physical Technical Institute, Tomsk State University, Tomsk, 634050, Russian Federation Department of Physics, Faculty of Education, Ain Shams University, Roxy, Cairo, 11341, Egypt Export Date: 31 May 2023 CODEN: IERME Correspondence Address: Beke, D.L.; Department of Solid State Physics, P. O. Box 400, Hungary; email: dbeke@delfin.unideb.hu AB - Simultaneous acoustic emission, AE, and DSC measurements under compression along [110]A direction were carried out on Ni49Fe18Ga27Co6 shape memory single crystals. The compression resulted in anomalous stressstrain loops with stress drops/jumps on it, reflecting a sudden formation/dissolution of a more stable (detwinned) martensite structural modification than the thermally induced (twinned) one. The final detwinned martensite, obtained below a certain temperature, was stable even after downloading: during heating it showed a burst-like recovery at about 35K higher transformation temperature than that of the thermally induced one, with an audible click. It was obtained that the number of acoustic events showed strong asymmetry: e.g. for stress induced transformations the number of hits for uploading was larger. Simultaneous measurements of stress-time curves and AE versus time revealed that in the nucleation/dissolution processes in both (up and down) directions, as an intermediate step, the twinned martensite was first formed and resulted in additional AE events. This was interpreted by the easy as well as difficult nucleation of the twinned and detwinned martensites, respectively. The stress drops on the uploading stress-strain curve were attributed to subsequent nucleation of the detwinned martensite from the twinned modification and were followed by a sharp decrease of the AE activity. This indicated that the formation of detwinned martensite is a sudden, fast process and can take place without significant elastic energy storage. This was also in agreement with the fact that during burst like thermal recovery the width of the transition was very small (Af ≅ As). Similarly, during downloading the stress jumps were interpreted as sudden dissolutions of the detwinned phase by retwinning and at all stress jumps there were local maxima on the AE activity curve. LA - English DB - MTMT ER - TY - JOUR AU - Boda, Róbert AU - Lázár, István AU - Keczánné Üveges, Andrea AU - Bakó, József AU - Tóth, Ferenc AU - Trencsényi, György AU - Kálmán-Szabó, Ibolya AU - Béresová, Monika AU - Sajtos, Zsófi AU - D. Tóth, Etelka AU - Deák, Ádám AU - Tóth, Adrienn AU - Horváth, Dóra AU - Gaál, Botond Ágoston AU - Daróczi, Lajos AU - Dezső, Balázs AU - Ducza, László AU - Hegedűs, Csaba TI - β-Tricalcium Phosphate-Modified Aerogel Containing PVA/Chitosan Hybrid Nanospun Scaffolds for Bone Regeneration JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 8 PG - 23 SN - 1661-6596 DO - 10.3390/ijms24087562 UR - https://m2.mtmt.hu/api/publication/33766598 ID - 33766598 N1 - Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, University of Debrecen, Debrecen, 4032, Hungary Department of Inorganic and Analytical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen, 4032, Hungary Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Debrecen, 4032, Hungary Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Debrecen, 4032, Hungary Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Debrecen, 4032, Hungary Department of Dentoalveolar Surgery, University of Debrecen, Debrecen, 4032, Hungary Department of Operative Techniques and Surgical Research, Faculty of Medicine, University of Debrecen, Debrecen, 4032, Hungary Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Debrecen, 4032, Hungary Department of Solid State Physics, University of Debrecen, Debrecen, 4002, Hungary Department of Oral Pathology and Microbiology, Faculty of Dentistry, University of Debrecen, Debrecen, 4032, Hungary Export Date: 24 May 2023 Correspondence Address: Hegedűs, C.; Department of Biomaterials and Prosthetic Dentistry, Hungary; email: hegedus.csaba.prof@dental.unideb.hu Funding details: European Commission, EC Funding details: European Cooperation in Science and Technology, COST, CA18125, GINOP-2.2.1-15-2017-00068 Funding details: European Regional Development Fund, ERDF Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding text 1: The research supported by project no. TKP2021-EGA-20 (Biotechnology) was implemented with support provided by the National Research, Development and Innovation Fund of Hungary, financed under the TKP2021-EGA funding scheme. The work was carried out under the COST Action CA18125 “Advanced Engineering and Research of AeroGels for Environment and Life Sciences” (AERoGELS). The research was supported in part by the GINOP-2.2.1-15-2017-00068 project. The projects were co-financed by the European Commission, the European Union, and the European Regional Development Fund. AB - Electrospinning has recently been recognized as a potential method for use in biomedical applications such as nanofiber-based drug delivery or tissue engineering scaffolds. The present study aimed to demonstrate the electrospinning preparation and suitability of β-tricalcium phosphate-modified aerogel containing polyvinyl alcohol/chitosan fibrous meshes (BTCP-AE-FMs) for bone regeneration under in vitro and in vivo conditions. The mesh physicochemical properties included a 147 ± 50 nm fibrous structure, in aqueous media the contact angles were 64.1 ± 1.7°, and it released Ca, P, and Si. The viability of dental pulp stem cells on the BTCP-AE-FM was proven by an alamarBlue assay and with a scanning electron microscope. Critical-size calvarial defects in rats were performed as in vivo experiments to investigate the influence of meshes on bone regeneration. PET imaging using 18F-sodium fluoride standardized uptake values (SUVs) detected 7.40 ± 1.03 using polyvinyl alcohol/chitosan fibrous meshes (FMs) while 10.72 ± 1.11 with BTCP-AE-FMs after 6 months. New bone formations were confirmed by histological analysis. Despite a slight change in the morphology of the mesh because of cross-linking, the BTCP-AE-FM basically retained its fibrous, porous structure and hydrophilic and biocompatible character. Our experiments proved that hybrid nanospun scaffold composite mesh could be a new experimental bone substitute bioactive material in future medical practice. LA - English DB - MTMT ER - TY - JOUR AU - Tóth, László Zoltán AU - Bronstein, Emil AU - Daróczi, Lajos AU - Shilo, Doron AU - Beke, Dezső TI - Scaling of Average Avalanche Shapes for Acoustic Emission during Jerky Motion of Single Twin Boundary in Single-Crystalline Ni2MnGa JF - MATERIALS J2 - MATERIALS VL - 16 PY - 2023 IS - 5 SN - 1996-1944 DO - 10.3390/ma16052089 UR - https://m2.mtmt.hu/api/publication/33745669 ID - 33745669 AB - Temporal average shapes of crackling noise avalanches, U(t) (U is the detected parameter proportional to the interface velocity), have self-similar behavior, and it is expected that by appropriate normalization, they can be scaled together according to a universal scaling function. There are also universal scaling relations between the avalanche parameters (amplitude, A, energy, E, size (area), S, and duration, T), which in the mean field theory (MFT) have the form E∝A3, S∝A2, S∝T2. Recently, it turned out that normalizing the theoretically predicted average U(t) function at a fixed size, U(t)=atexp−bt2 (a and b are non-universal, material-dependent constants) by A and the rising time, R, a universal function can be obtained for acoustic emission (AE) avalanches emitted during interface motions in martensitic transformations, using the relation R~A1−φ too, where φ is a mechanism-dependent constant. It was shown that φ also appears in the scaling relations E~A3−φ and S~A2−φ, in accordance with the enigma for AE, that the above exponents are close to 2 and 1, respectively (in the MFT limit, i.e., with φ= 0, they are 3 and 2, respectively). In this paper, we analyze these properties for acoustic emission measurements carried out during the jerky motion of a single twin boundary in a Ni50Mn28.5Ga21.5 single crystal during slow compression. We show that calculating from the above-mentioned relations and normalizing the time axis of the average avalanche shapes with A1−φ, and the voltage axis with A, the averaged avalanche shapes for the fixed area are well scaled together for different size ranges. These have similar universal shapes as those obtained for the intermittent motion of austenite/martensite interfaces in two different shape memory alloys. The averaged shapes for a fixed duration, although they could be acceptably scaled together, showed a strong positive asymmetry (the avalanches decelerate much slower than they accelerate) and thus did not show a shape reminiscent of an inverted parabola, predicted by the MFT. For comparison, the above scaling exponents were also calculated from simultaneously measured magnetic emission data. It was obtained that the φ values are in accordance with theoretical predictions going beyond the MFT, but the AE results for φ are characteristically different from these, supporting that the well-known enigma for AE is related to this deviation. LA - English DB - MTMT ER -