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691.
Hasene Keskin Çavdar Hakkı Bilgin Sibel Fadıloğlu Fatih Mehmet Yılmaz 《European Journal of Lipid Science and Technology》2023,125(3):2200089
This research aimed to analyze ultrasound (UAE) and microwave-assisted extraction (MAE) as novel technologies for utilizing gilthead seabream (Sparus aurata) by-products to produce high-quality fish oil for human consumption. The impacts of extraction parameters, namely, temperature, time, solvent-to-solid ratio, and their interactions on the extraction yield, are investigated using response surface methodology (RSM), and a central composite rotatable design. The optimized conditions are 15.47 mL g−1 of solvent-to-solid ratio, 38 min, and 42 °C for UAE and 15.84 mL g−1 of solvent-to-solid ratio, 18 min, and 40 °C for MAE. Under optimal conditions, the maximum extraction yields are 38.40 and 36.70% (g/g) for UAE and MAE, respectively. Both UAE and MAE have significantly higher mass transfer rates (61.70 and 121.58 g h−1, respectively) than Soxhlet extraction (10.78 g h−1). The fatty acid composition, physicochemical, and oxidation analyses of fish oils confirm the suitability of both UAE and MAE for the recovery of high-quality oils from fish processing by-products. The valorized oils mainly include unsaturated fatty acids (≈75%) and are rich in oleic acid. Furthermore, scanning electron microscopy analysis reveals that the key driving force for fast oil extraction is the structural degradation of fish by-products caused by ultrasound and microwave. Practical Applications: Due to environmental and economic viewpoints, the validation of fish oil from fish industry by-products has become a popular research topic recently. Alternative recovery techniques such as ultrasound- (UAE) and microwave-assisted extraction (MAE) protocols may have additional benefits in producing functional oils. Interactive effects of process parameters determine the success of the extraction technique; therefore optimization is a critical approach when applying the extraction protocols. This study shows that UAE and MAE techniques significantly enhanced oil extraction rate from gilthead seabream (Sparus aurota) by-products at lower temperatures and by using lower amounts of solvent. UVA and MAE increase oxidative stability and do not change the fatty acid composition. Hence, the by-product of the gilthead seabream can be a sustainable and food-grade fish oil source and UAE and MAE can be a good alternative to the conventional (Soxhlet) extraction by providing high yield and quality oil. 相似文献
692.
Neural Computing and Applications - Machine learning algorithms spend a lot of time processing data because they are not fast enough to commit huge data sets. Instance selection algorithms... 相似文献
693.
Enes DEDEOGLU Himmet Toprak KESGIN Mehmet Fatih AMASYALI 《Frontiers of Computer Science》2024,18(4):184315
The use of all samples in the optimization process does not produce robust results in datasets with label noise. Because the gradients calculated according to the losses of the noisy samples cause the optimization process to go in the wrong direction. In this paper, we recommend using samples with loss less than a threshold determined during the optimization, instead of using all samples in the mini-batch. Our proposed method, Adaptive-k, aims to exclude label noise samples from the optimization process and make the process robust. On noisy datasets, we found that using a threshold-based approach, such as Adaptive-k, produces better results than using all samples or a fixed number of low-loss samples in the mini-batch. On the basis of our theoretical analysis and experimental results, we show that the Adaptive-k method is closest to the performance of the Oracle, in which noisy samples are entirely removed from the dataset. Adaptive-k is a simple but effective method. It does not require prior knowledge of the noise ratio of the dataset, does not require additional model training, and does not increase training time significantly. In the experiments, we also show that Adaptive-k is compatible with different optimizers such as SGD, SGDM, and Adam. The code for Adaptive-k is available at GitHub. 相似文献
694.
Automated steel surface defect detection and classification using a new deep learning-based approach
Demir Kursat Ay Mustafa Cavas Mehmet Demir Fatih 《Neural computing & applications》2023,35(11):8389-8406
Neural Computing and Applications - In this study, a new deep learning-based approach has been developed that detects and classifies surface defects that occur in the steel production process. The... 相似文献
695.
Sefa Durmaz Ozlem Ozgenc Keles Ugur Aras Yusuf Ziya Erdil Fatih Mengeloglu 《Coloration Technology》2023,139(4):430-440
In recent years, wood-plastic composites (WPCs) have become among the most popular engineering materials. Most of their usage areas are outdoors, where they encounter various damaging factors. The weathering conditions cause significant deterioration to WPC surfaces, which negatively influences their service life. In this study, zinc oxide nanoparticles at different concentrations (1%, 3%, 5%, 10%) were added to a high-density polyethylene-based WPC matrix. The effect of zinc oxide nanoparticles on the weathering performance of WPC was evaluated after 840 hours of an artificial weathering test. The highest colour changes (∆E*) were monitored with control samples exposed for 840 hours. Adding zinc oxide nanoparticles improved the ultraviolet (UV) resistance and decreased the colour changes. The wood flour content also affected the colour changes on the WPC surface. A combination of 10% zinc oxide nanoparticles and 50% wood flour content provided the lowest colour changes. The barrier effect of nanoparticles protected the WPC surfaces from UV light. Zinc oxide nanoparticles also positively affected the load transfer, which restricted the reduction in mechanical properties after the weathering test. The degradation on the surface of WPCs was also investigated using attenuated total reflectance-Fourier Transform–infrared analysis. The changes in the characteristic bands of polymer and wood indicated that surface degradation was inevitable. Light and scanning electron microscopy images also demonstrated micro-cracks and roughness on the surface of WPCs. It is concluded that UV degradation is unavoidable, but zinc oxide nanoparticles can improve surface resistance against weathering conditions. 相似文献
696.
Ismail Eş Abdullah Kafadenk M. Burak Gormus Fatih Inci 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(27):2206510
Although hypodermic needles are a “gold standard” for transdermal drug delivery (TDD), microneedle (MN)-mediated TDD denotes an unconventional approach in which drug compounds are delivered via micron-size needles. Herein, an isotropic XeF2 dry etching process is explored to fabricate silicon-based solid MNs. A photolithographic process, including mask writing, UV exposure, and dry etching with XeF2 is employed, and the MN fabrication is successfully customized by modifying the CAD designs, photolithographic process, and etching conditions. This study enables fabrication of a very dense MNs (up to 1452 MNs cm−2) with height varying between 80 and 300 µm. Geometrical features are also assessed using scanning electron microscopy (SEM) and 3D laser scanning microscope. Roughness of the MNs are improved from 0.71 to 0.35 µm after titanium and chromium coating. Mechanical failure test is conducted using dynamic mechanical analyzer to determine displacement and stress/strain values. The coated MNs are subjected to less displacement (≈15 µm) upon the applied force. COMSOL Multiphysics analysis indicates that MNs are safe to use in real-life applications with no fracture. This technique also enables the production of MNs with distinct shape and dimensions. The optimized process provides a wide range of solid MN types to be utilized for epidermis targeting. 相似文献
697.
Talal Lahreche Fatih Ozogul Yilmaz Ucar Abderrahmane Ameur 《International Journal of Food Science & Technology》2023,58(1):228-237
The impacts of natural preservatives such as olive leaf (Olea europaea L.) and sweet marjoram (Origanum majorana L.) extracts (OLE and SME) and cold storage on the fatty acid profiles of vacuum-packaged tuna-like muscles were evaluated. At the end of the storage time, the lowest content of the total saturated fatty acids (SFA) was observed in both ordinary and dark muscles of the treated samples (OLE and SME) whereas the highest content was found in their counterparts from the untreated samples (control). The total polyunsaturated fatty acid (PUFA) and total monounsaturated fatty acid (MUFA) contents decreased markedly in both ordinary and dark muscles of the control samples. In contrast, treated samples remained relatively stable throughout the storage time since the employment of plant extracts had protective effects against lipid oxidation and help maintain MUFA and PUFA levels in frigate tuna muscles. In addition, the PUFA/SFA ratio and polyene index which are considered important dietetic parameters showed that the used plant extracts (OLE and SME) did not result in a reduction in the PUFA/SFA ratio and prevented PUFA damage in both frigate tuna muscles during storage. Thus, the use of plant extracts such as OLE and SME can be recommended as natural preservatives for the fish processing industry. 相似文献