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Öğe Determination of tensile strength of cementitious composites using fracture parameters of two-parameter model for concrete fracture(Elsevier, 2022) İnce, Ragıp; Fenerli, CenkIn this study, the formulation of the two-parameter model based on the size effect proposed by previous researchers was initially improved to be much more practical. Subsequently, six series of notched and unnotched beams with a size ratio of 1:4 and notched and unnotched square prismatic specimens with a size ratio of 1:6 were tested to verify this modified formulation. The peak loads obtained from the fracture tests of the notched specimens were examined using the two-parameter model. Then, the test results of the unnotched bending and splitting specimens were simulated according to the modified formulation. Furthermore, this formulation was applied to extensive test data obtained from the direct tension specimens with double edge notches and from the unnotched specimens in the literature to derive the direct tensile strength of concrete. Finally, when comparing the results of this study to the previous studies, there were slight differences among the other formulas, except for the one that covered splitting specimens.Öğe EMG Sinyallerinin Kısa Zamanlı Fourier Dönüşüm Özellikleri Kullanılarak Yapay Sinir Ağları ile Sınıflandırılması(Fırat University, 2019) Arı, Ali; Ayaz, Furkan; Hanbay, DavutEMG sinyali kasların kasılması sırasında oluşan elektriksel aktivasyonun ölçülmesi işlemidir. EMG sinyali, kasların nöral aktivasyonu ve dinamikleri hakkında bilgi sağlamaktadır. Bu nedenle EMG sinyallerinin işlenmesi; sinir hastalıkları teşhisi, protez cihazlar ve insan makine etkileşiminde olmak üzere birçok alanda giderek daha etkin olarak kullanılmaya başlanmıştır. Özellikle EMG sinyallerinden hareket tespiti ve EMG sinyallerinin sınıflandırılması bu çalışmalar için önem teşkil etmektedir. Bu amaçla yapılan çalışmada EMG sinyallerinden hareket tespiti yapılması amaçlanmıştır. İlk olarak 6 farklı harekete ait EMG sinyalleri alınmış ve bu sinyallere Kısa Zamanlı Fourier Dönüşümü (KZFD) uygulanmış ve sinyaller Zaman-Frekans (Z-F) düzleminde gösterilmiştir. Daha sonra bu Z-F gösterimlerinden öznitelik çıkarmak amacıyla gösterimler bölütlenmiş ve her bir pencereye ait istatistiksel öznitelikler, Yerel İkili Örüntü (YİÖ) değerleri ve Gri Seviye Eş oluşum Matrisi (GSEM) hesaplanarak EMG sinyaline ait öznitelikler çıkartılmıştır. Çıkarılan bu öznitelikler Yapay Sinir Ağı (YSA) ile sınıflandırılmış ve sistemin başarımı ölçülmüştür. Sistemin doğruluk başarımı ortalama %92 olarak hesaplanmıştırÖğe Evaluation of Noise Emission in A Textile Plant(Malatya Turgut Ozal University, 2020) Duran, Zekeriya; Genç, Mehmet; Doğan, Tuğba; Erden, BülentTextile industry is characterized by the use of complicated machinery in mass production methods in order to meet increased consumption demands. This situation brings with it some issues for the employees. Many of the machines used in textile industry are operating at high noise levels. In this study, noise measurements taken from dyeing/finishing and weaving divisions in an integrated textile factory in Malatya city, Turkey were evaluated. Frequency distribution of dominant noise is also examined. Workers in weaving division were exposed to higher levels of noise than those in dyeing/finishing. Accordingly, the noise level in weaving ranged from 99.2 to 101.1 dBA, while that in dyeing/finishing ranged from 77.1 to 79.3 dBA. It is also outside the 4000 Hz frequency zone, where the dominant frequencies of the maximum noise levels exposed by those working in the measured divisions fall in the middle frequency range to which the ear is most sensitive. Considering the frequency distribution, noise levels in the 4000 Hz region are calculated to be between 84.2 and 86.8 dBA in the weaving division and 60.0 to 61.9 dBA in the dyeing/finishing division. A noise histogram showed that noise in the weaving division had spread over a wider range than the dyeing/finishing division.Öğe Determination of energy value and ash-sulfur content of clean fuel obtained from lignite carbonization at different heating rates(2021) Aksoğan Korkmaz, AydanCarbonization (low-temperature pyrolysis) is an economical and efficient method used to obtain solid products from lignite and improve calorific value. This research focused on the morphological and structural properties as well as the effect of pyrolysis heating rate on the solid product yield. Experiments were performed at 500°C, with a nitrogen gas flow of 200 mL/min, residence time of 60 min, and different heating rates (5, 10, 15, and 20°C/min). Proximate and ultimate analyses of the char products obtained from each experiment were performed. The changes in the char morphology and chemical structures were investigated via scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and the Brunauer-Emmett-Teller (BET) method. The effects of the different heating rates on the char structure were determined. The highest char yield (52.98%) and the highest C (49.45%) and the lowest S (2.51%) contents were determined in the char obtained from a heating rate of 15°C/min. The highest calorific value (5603 kcal/kg) was also calculated at this heating rate. These results showed that the chemical and physical properties of char at a heating rate of 15°C/min were better than those at other heating rates. As a result, a valuable solid fuel with high energy value could be obtained from low quality lignite.Öğe Physical exercise may improve problem-solving skills and emotional intelligence in patients with relapsing-remitting multiple sclerosis: A cross-sectional study(Elsevier B.V. All, 2022) Taşcı, İrem; Demir, Caner Feyzi; Bilek, Furkan; Albayrak, SaitBackground: Multiple sclerosis is a disease that can reduce the quality of life with a physical disability, neuro-psychiatric disorders, and cognitive dysfunctions. Therefore, multiple sclerosis treatment should include treatments for cognitive and neuropsychiatric disorders and pharmacological treatments. This study aimed to examine the effects of exercise on neuropsychiatric disorders, problem-solving skills, and emotional intelligence in multiple sclerosis patients. Methods: Thirty-six female relapsing-remitting multiple sclerosis patients aged between 18 and 45 years, with an Expanded Disability Status Scale between 1 and 3, who were diagnosed with definitive multiple sclerosis according to the revised McDonald criteria were included in the study. Participants completed outcome measures before and after the 12-week exercise program. Demographic/clinical information of the participants was obtained at baseline, neurological examinations were performed, and graded exercise testing on a bicycle ergometer was performed to determine aerobic capacity. Short Form-12 Version 2, Hospital Anxiety and Depression Scale, Modified Fatigue Impact Scale, Problem-Solving Inventory, Emotional Intelligence Scale were evaluated before and after the exercise program of the participants. Results: While a significant increase was observed in the HRpeak values of the participants after the exercise (p <0.05), the VO2max values also showed a highly significant difference compared to the pre-treatment values. (p <0.01). While a significant difference was detected in the mental subparameter of Short Form-12 (p < 0.05), a high level of significant difference was found in the physical subparameter (p< 0.01). While no significant difference was observed in the Hospital Anxiety and Depression Scale anxiety subparameter (p > 0.05), a significant difference was found in the depression subparameter (p < 0.01). There was a significant difference in Modified Fatigue Impact Scale physical and cognitive subparameters compared to pre-treatment (p < 0.01). A significant difference was observed in the Emotional Intelligence Scale total score after the treatment (p < 0.01). Conclusions: The results of our study showed that exercise in relapsing-remitting multiple sclerosis patients provided significant improvements in emotional intelligence, improved neuropsychiatric parameters, and increased problem-solving skills. In addition, to the best of our knowledge, this study is the first study in the literature to investigate the effect of physical activity exercises on problem-solving skills in multiple sclerosis patients.Öğe Residual strength prediction based on size effect of cracked concrete members(ICE Publishing, 2021) İnce, Ragıp; Fenerli, CenkIn engineering materials, defects, such as cracks, may occur during production and/or owing to various reasons. One of the aims of fracture mechanics is to determine the fracture toughness-based residual strength of structural members with cracks. A quasi-brittle material, such as concrete or rock, may include certain defects, such as voids and cracks, even before being exposed to loads. Experimental analyses on concrete members indicated that specimens’ nominal strength values decreased as their sizes increased while specimen geometry remained the same. In fracture mechanics, this condition is defined as the ‘size effect’ in both concrete and reinforced concrete units. In the literature, numerous theoretical and experimental studies have been conducted on beams, while compact split-tension specimens, particularly notched ones, are limited. In this study, six series of notched beams with three different sizes and notched square prismatic specimens with four different sizes were tested. According to the test results, the peak loads were analysed by using the fundamental theorem of the modified size effect law. In conclusion, two formulae were proposed to predict the flexural strength and the splitting strength of quasi-brittle bodies with cracks.Öğe Effect of fly ash and marble powder on and flow properties and compressional strength of grouts(Baski, 2019) Sis, Hikmet; Kıyak, Tufan; Fenerli, Cenk; Genç, MehmetCoal fly-ash and marble powders are two environmentally important industrial waste materials that should be utilized. It is known that they are used as additives in concrete production for many years. In this study, the usability of fly-ash and marble powder in grout production was investigated. Flyash and marble powder utilized in the tests were obtained from Soma (Manisa) power plant and Akçadag (Malatya) region, respectively. Pozzalanic fly-ash and reactive marble powder were used in grout mixtures as partial replacement materials for cement and aggregate, respectively. Flow and strength properties of the grouts prepared at different water/cement ratios were tested and the effect of the additives were determined. Rheological properties of the mixtures were tested at a wide range of shear stress-shear rate by utilizing a rheometer. Additionally, the prepared mixtures were cast into moulds and the 28 day strength of the cubes were determined by uniaxial compression tests. Test results showed that the increasing water/cement ratio increased the fluidity the grout mixtures, but inversely affected the strength of hardened grouts. The results showed that addition of fly ash decreased the 28 days strength of hardened grout by improved the fluidity of fresh grout to some extend. On the other hand, marble powder decreased the fluidity of mixtures but increased the strength of hardened grout significantly. Copyright © IMCET 2019 International Mining Congress and Exhibition of Turkey. All rights reserved.Öğe Düşük ısıl değerli linyit ve atık biyokütlenin dumansız yakıt olarak kullanılabilirliğinin araştırılması(Bursa Uludağ Üniversitesi, 2021) Korkmaz, Aydan AksoğanEnerji, bir toplumun en önemli temel ihtiyaçlarından biridir. Gelişmekte olan ve az gelişmiş ülkelerdebu enerji ihtiyacının çoğu fosil enerji kaynaklarından karşılanmaktadır. Bu kaynaklar, hem sınırlı hem deçevreyi olumsuz etkiledikleri için, sürekli olarak kullanılmaları uygun değildir. Enerjinin sürekliliği içinbiyokütle gibi yenilenebilir enerji kaynaklarından da maksimum düzeyde faydalanmak gereklidir.Biyokütle; doğrudan yakma, piroliz ve gazlaştırma gibi bazı çevirim teknikleri kullanılarak katı, sıvı ve gazyakıtlara dönüştürülebilmektedir. Biyokütledeki yüksek H içeriği, kömürle birlikte pirolizi sırasındahidrojen kaynağı olarak kullanılmaktadır. Piroliz esnasında biyokütleden yayılan H ve OH radikalleri,kömürün aromatik halkalarındaki kırılmaları desteklemektedir. Kömür ile biyokütlenin pirolizinden eldeedilen katı ürünün yakılmasıyla atmosferi kirleten SO2 ve NOx gibi içeriklerin azaltılması mümkündür. Buçalışmada, linyit ve ceviz kabuğunun farklı karışım oranları ve sıcaklıklarda pirolizi gerçekleştirilmiştir.Elde edilen katı ürünün, kalorifik değerleri ve C, S, N içerikleri belirlenmiştir. Artan biyokütle oranıyla,dumansız yakıtta olumlu değişiklikler olduğu belirlenmiştir.Öğe Falcon Konsantratör ile Ermenek Linyitinden Kül ve Kükürdün Uzaklaştırılması(Afyon Kocatepe Üniversitesi, 2021) Aksoğan Korkmaz, AydanBir kömürün kalitesini belirleyen en önemli içeriği kül ve kükürttür. Bu bileşenler genellikle kömür içerisinde, ince taneler halinde dissemine şekilde bulunmaktadır. Dolayısıyla kömürlerden kül ve kükürdün uzaklaştırılması oldukça zordur. Falcon konsantratör, özellikle ultra ince kömürlerin yüksek merkezkaç kuvvetleri ile zenginleştirildiği yeni teknolojilerden biridir. Bu çalışmada, Konya Ermenek linyitinin Falcon Konsantratörü ile zenginleştirilme olanakları incelenmiştir. 1,5 l/dk besleme hızı sabit tutularak, -75+38 µm tane boyutlu linyite, farklı katı oranları (%20, %30, %40 ve %50) ve farklı merkezkeç kuvvetlerinde (20G, 100G, 176G ve 300G) testler uygulanmıştır. En iyi sonuçlar, %40-50 katı oranı ve 100G’den büyük merkezkaç kuvvetlerde elde edilmiştir.Öğe Use of water quality index and multivariate statistical methods for the evaluation of water quality of a stream affected by multiple stressors: A case study(Elsevier, 2020) Varol, MemetTherefore, water quality of the stream is of great importance. In this study, multivariate statistical techniques (MSTs) and water quality index (WQI) were applied to assess water quality of the stream affected by multiple stressors such as untreated domestic sewage, effluents from fish farms, agricultural runoff and streambank erosion. For this, 16 water quality parameters at five sites along the stream were monitored monthly during one year. Most of parameters showed significant spatial variations, indicating the influence of anthropogenic activities. All parameters except TN (total nitrogen) showed significant seasonal differences due to high seasonality in WT (water temperature) and water flow. The spatial variations in the WQI were significant (p < 0.05) and the mean WQI values ranged from 87.6 to 95.3, indicating “good” to “excellent” water quality in the stream. Cluster analysis classified five sites into three groups, that is, clean region, low polluted region and very clean region. Stepwise temporal discriminant analysis (DA) identified that pH, WT, Cl?, SO42?, COD (chemical oxygen demand), TSS (total suspended solids) and Ca2+ are the parameters responsible for variations between seasons, and stepwise spatial DA identified that DO (dissolved oxygen), EC (electrical conductivity), NH4–N, TN (total nitrogen) and TSS are the parameters responsible for variations between the regions. Principal component analysis/factor analysis revealed that the parameters responsible for water quality variations were mainly associated with suspended solids (both natural and anthropogenic), soluble salts (natural) and nutrients and organic matter (anthropogenic).Öğe Modeling of the effect of falcon concentrator parameters on lignite deashing with Taguchi orthogonal design(Taylor & Francis, 2021) Aksoğan Korkmaz, AydanIn this study, the deashing of Sivas-Kangal (Turkey) lignite was carried out under different conditions. Solids ratio (20%, 30%, 40% and 50% by weight), centrifugal force (20, 100, 176 and 300 G), feed rate (0.5, 1.0, 1.5 and 2.0 L/min) and particle size (?300, ?212, ?150 and ?75 µm) were selected as experimental parameters. Taguchi experimental design was used to optimize Falcon parameters. The orthogonal array design plan was determined as L16 according to the available variables. Since the study aims to obtain clean coal, ash contents (AC) from the results are taken into consideration. And signal/noise (S/N) ratios of each test condition were calculated. As a result of the Falcon tests performed under the optimization conditions for Taguchi, it was determined that the S/N ratio was 27.38 and the AC was 13.68% (expected AC 13.43%). The minimum ash content was achieved using the optimized conditions were: solids ratio of 30%, centrifugal force 100 G, feed rate 2 L/min and particle size ?75 µm. As a result of Falcon experiments with Taguchi design, AC decreased from 43.66% in raw coal to 13.68% in clean coal.Öğe Highly Active Fe3O4@SBA-15@NHC-Pd Catalyst for Suzuki–Miyaura Cross-Coupling Reaction(Springer, 2021) Akkoç, Mitat; Buğday, Nesrin; Altın, Serdar; Özdemir, İsmail; Yaşar, SedatA novel Pd-NHC functionalized magnetic Fe3O4@SBA-15@NHC-Pd was synthesized and used as an efficient heterogeneous catalyst in the Suzuki–Miyaura C–C bond formation reactions. The Fe3O4@SBA-15@NHC-Pd characterized by X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray analysis (EDX), Thermogravimetric Analysis (TGA), Differential Thermal Analysis (DTA). The Inductively Coupled Plasma-Optical emission spectroscopy (ICP-OES) analysis was used to determine the exact amount of Pd (0.33 wt%) in Fe3O4@SBA-15@NHC-Pd. The TEM images of the catalyst showed the existence of palladium nanoparticles immobilized in the catalyst's structure, while no reducing agent was used. The NHC moieties in the catalyst structure could be stabilize Pd(0) nanoparticles prevents agglomeration. The magnetic catalyst was effectively used in the Suzuki–Miyaura cross-coupling reaction of substituted phenylboronic acid derivatives with (hetero)aryl bromides in the presence of a K2CO3 at room temperature in aqueous media and magnetic catalyst could be simply extracted from the reaction mixture by an external magnet. Different aryl bromides were converted to coupled-products in excellent yields with spectacular TOFs values (up to 1,960,339 h?1); in the presence of 1 mg of Fe3O4@SBA-15@NHC-Pd catalyst (contains 3.1?×?10–6 mol% Pd) at room temperature in aqueous media. After reusability experiments, it is found that this catalyst was effectively used up to ten times in the reaction with almost consistent catalytic efficiency. A decrease in the activity of the 10th reused catalyst was found as 9%.Öğe Burr measurement method based on burr surface area(Korean Society for Precision Engineering, 2020) Bahçe, Erkan; Özdemir, BurakOne of the major issues of drilling operations pertains to the formation of burrs, which greatly influences the accuracy of the manufactured parts, and, thus, the capability to meet the desired performance of the part. To remove or prevent these burrs, their geometry must be measured accurately, even though they are sharp and irregular in shape. The accurate measurement of the geometry of a burr will lead to the development of a proper deburring method. In this work, the authors describe a simple and convenient new measurement technique for drilling burr profiles and a developed drilling burr measurement system based on surface area. The new method presented in this research aims at providing a comparative evaluation of the height, arc length and area of the burr, as well as its geometrical characteristics. When the average height and arc length measurement methods are compared with the area measurement method, large deviations in burr height are detected. In particular, these deviations increase more in non-uniform burrs. In the measurement of burr size, the new developed method is based on area measurement and is carried out using a computer. Therefore, there is no deviation between the measurements. In contrast, the average deviation ranges for the height and arc length measurement methods are found to be 9.94–48.14% and 6.07–18.82%, respectively.Öğe Biyoakustik ses verileri üzerinde çeşitli sınıflandırıcı algoritmalarının temel bileşen analizi kullanılarak performans karşılaştırması(IEEE (Institute of Electrical and Electronics Engineers), 2019) Onal, Merve Kesim; Avcı, Engin; Türkoğlu, İbrahimDoğal ortamlarda alınan seslerin tanınması laboratuvar ortamında alınan veya yapay olarak oluşturulan seslerin tanınmasından daha zordur. Özellikle benzer canlıların çıkardıkları sesler tanınmayı zorlaştıran bir etkendir. Bu çalışmada doğal ortamlardan alınmış farklı aile, cins ve türdeki anuran seslerinin tanınmaları için makine öğrenmesi tekniklerinin karşılaştırılmaları yapılmıştır. Veri seti olarak UCI veri tabanındaki “Anuran Calls (MFCCs)” kullanılmıştır. Bu veri seti doğal ortamlardan alınan anuran seslerinin Mel Frekans Kepstral Katsayılarını içermektedir. Veri seti üzerinde Makine Öğrenmesi algoritmalarından Lojistik Regresyon, Destek Vektör Makineleri ve Karar ağaçları sınıflandırıcılarınn performansları karşılaştırılmıştır. Ayrıca Temel Bileşen Analizi ile veri setinde boyut indirgemesi yapılmış ve sınıflandırıcı performanslarının değişimleri karşılaştırılmıştır.Öğe Balsa çekirdekli sandviç kompozitlerin darbe davranışlarının deneysel olarak incelenmesi(Tüm Bilim İnsanları ve Akademisyenler Derneği, 2021) Önal, Tuğberk; Temiz, ŞemsettinSandviç kompozitler, kullanım alanlarına bağlı olarak farklı darbe yüklerine maruz kalabilmektedir. Yapının darbe yükü altındaki davranışları, tasarım açısından önemli bir parametredir. Bu çalışmada, 4mm, 6mm, 8mm ve 10mm kalınlıktaki balsa odunlarının çekirdekte kullanıldığı sandviç yapılara düşük hızlı darbe testi uygulanmıştır. Alt ve üst yüzeylerde 8 ve12 tabakalı, [±45º]s yönlenme açılı cam elyaf/epoksi kompozit malzemeler kullanılmıştır. Dış yüzey tabaka sayısı ve çekirdek kalınlığının darbe davranışları üzerindeki etkisi deneysel olarak incelenmiştir. Vakum infüzyon yöntemi ile üretilen sandviç malzemelere 15J, 30J, 45J ve 60J enerji değerlerinde düşük hızlı darbe testleri yapılmıştır. Sonuçta, tepki kuvveti-deplasman, enerji-zaman ve eş enerji grafikleri incelenmiştir. Dış yüzey tabaka sayısı artışına bağlı olarak temas kuvvetinin arttığı, fakat absorbe edilen enerjinin azaldığı belirlenmiştir. Bununla birlikte, çekirdek kalınlığının arttırılması sandviç yapıda absorbe edilen enerjiyi arttırdığı gözlemlenmiştir.Öğe A study on the investıgation of improvement in coal liquefaction product efficiency(Eskişehir Teknik Üniversitesi, 2019) Aksoğan Korkmaz, Aydan; Bentli, İsmailThe aim of this study is to improve the yields of Malatya-Arguvan lignite liquefaction products (char, preasphaltene, asphaltene, oil-gas). For this purpose, the liquefaction experiments of coal which was firstly raw and then enriched by spiral have been carried out. The chemical characterizations of the obtained products have been determined by proximate and ultimate analysis. The composition of the oil was identified by GC-MS. As a result of the enrichment, the char yield decreased by 9.28% whereas the preasphaltene yield increased by 5.31% and the oil + gas yield increased by 4.18%. Total conversion increased from 47.57% to 56.85%. It has been concluded that the enrichment process has a positive effect on the liquefaction yields.Öğe A study on the optoelectronic parameters of 4-chloromethyl-7-hydroxy coumarin in various solvents and concentrations(Türkiye Kimya Derneği, 2021) Kurt, Adnan; Gündüz, Bayram; Koca, MuratA coumarin derivative, namely 4-chloromethyl-7-hydroxy coumarin (CMEHC), was synthesized in order to test the concentration and solvent effect on its optical properties. The spectral characterization of this compound was accomplished by FTIR and 1H-NMR techniques. The UV absorption spectra of CMEHC compound in various solvents (THF, DMSO, DMF) were recorded with a UV–VIS spectrophotometer. The optical parameters such as maximum peak position, absorption band edge, and direct allowed bandgap were reported for these solvents and also various concentrations. The lowest direct allowed bandgap was obtained with THF. The absorbance spectra of CMEHC compound were dominant at the near ultraviolet region. The refractive index values were compared with each other using Moss, Ravindra, Herve-Vandamme, Reddy and Kumar-Singh relations.Öğe N-heterocyclic carbene Pd(II) complex supported on Fe3O4@SiO2: Highly active, reusable and magnetically separable catalyst for Suzuki-Miyaura cross-coupling reactions in aqueous media(Elsevier, 2021) Akkoç, Mitat; Buǧday, Nesrin; Altın, Serdar; Kiraz, Nadir; Yaşar, Sedat; Özdemir, İsmailA new type magnetic nano Fe3O4@SiO2@NHC@Pd-MNPs heterogeneous catalyst was fabricated and characterized by Fourier Transform Infrared (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Energy Disperse X-ray analysis (EDX), Thermogravimetric Analysis (TGA), Differential Thermal Analysis (DTA), and Scanning Electron Microscopy (SEM). The loading amount of Palladium (Pd) to magnetic nano Fe3O4@SiO2@NHC@Pd-MNPs was measured by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analysis. The catalytic activity of magnetic nano Fe3O4@SiO2@NHC@Pd-MNPs heterogeneous catalyst was examined on Suzuki-Miyaura cross-coupling reactions of aryl halides with different substituted arylboronic acid derivatives. All coupling reactions yielded excellent results and high TOF (up to 76528 h?1) in the presence of 2 mg of Fe3O4@SiO2@NHC@Pd-MNPs catalyst (0.0197 mmolg?1, 0.00394 mmol%Pd) at 80 °C in 2-propanol/H2O (1:2). In addition, the magnetic nano Fe3O4@SiO2@NHC@Pd-MNPs catalyst was easily recovered by using an external Nd-magnet and reused for the Suzuki cross-coupling reactions. The catalyst showed strong structural and chemical stability and was reused six times without losing its catalytic activity substantially.
