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The selection of parameters affects the surface roughness in the additive manufacturing process. This study aims to determine the optimal combination of input parameters for predicting and minimising the surface roughness of samples produced by Fused Deposition Modelling on a 3D printer using a cascade-forward neural network (CFNN) and genetic algorithm. Box–Behnken Design with four independent printing parameters at three levels is used, and 25 parts are fabricated with a 3D printer. Roughness tests are performed on the fabricated parts. Models generated by the hybrid algorithm achieve the best results for predicting and optimising surface roughness in 3D-printed parts. The surface roughness prediction accuracy of the trained CFNN with optimised parameters is more accurate compared to previous random test results.

Poly(ethylene oxide) (PEO)-based polymer electrolytes are a promising class of materials for use in lithium-ion batteries due to their high ionic conductivity and flexibility. In this study, the effects of polymer architecture including linear, star, and hyperbranched and salt (lithiumbis(trifluoromethanesulfonyl)imide (LiTFSI)) concentration on the glass transition (Tg), microstructure, phase diagram, free volume, and bulk viscosity, all of which play a significant role in determining the ionic conductivity of the electrolyte, have been systematically studied for PEO-based polymer electrolytes. The branching of PEO widens the liquid phase toward lower salt concentrations, suggesting decreased crystallization and improved ion coordination. At high salt loadings, ion clustering is common for all electrolytes, yet the cluster size and distribution appear to be strongly architecture-dependent. Also, the ionic conductivity is maximized at a salt concentration of [Li/EO ≈ 0.085] for all architectures, and the highly branched polymers displayed as much as three times higher ionic conductivity (with respect to the linear analogue) for the same total molar mass. The architecture-dependent ionic conductivity is attributed to the enhanced free volume measured by positron annihilation lifetime spectroscopy. Interestingly, despite the strong architecture dependence of ionic conductivity, the salt addition in the highly branched architectures results in accelerated yet similar monomeric friction coefficients for these polymers, offering significant potential toward decoupling of conductivity from segmental dynamics of polymer electrolytes, leading to outstanding battery performance.

In this study, new 4-chloro-5-(2-isopropyl-5-methylphenoxy)phthalonitrile compound, containing bioactive thymoxy group, and its metal-free phthalocyanine and metallo-phthalocyanine derivatives were synthesized for the first time. Their structures were determined by spectroscopic methods such as FTIR, UV–Vis, 1H-, and 13C-NMR (for phthalonitrile derivative), MALDI-TOF mass spectrometry (for phthalocyanine derivatives) and elemental analysis as well. The phthalocyanines showed excellent solubility in polar and nonpolar solvents without aggregation and absorb at long wavelengths with their high molar coefficient. In N,N-dimethylformamide, the effects of the type of central metal ions [metal-free, indium(III) acetate, lutetium(III) acetate, magnesium(II) or zinc(II)] in the phthalocyanine, containing bioactive thymoxy group, cavity on the spectroscopic, photophysical, and photochemical properties of the phthalocyanines were determined. These features are compared with each other. Lutetium(III) acetate phthalocyanine did not show any fluorescence, while metal-free phthalocyanine and indium(III) acetate phthalocyanine showed low fluorescence. It was determined that magnesium phthalocyanine significantly enriched the fluorescence, and zinc phthalocyanine had appropriate and sufficient fluorescence. Lutetium(III) acetate and zinc(II), especially indium(III) acetate phthalocyanines, could produce large amounts of singlet oxygen. Metal-free and magnesium phthalocyanines had the capacity to produce sufficient singlet oxygen (it means production of enough amount of singlet oxygen by a photosensitizer candidate during PDT applications). All phthalocyanines have sufficient and suitable photostability (it means an ideal photosensitizer should be stable under light irradiation until complete its PDT activation, and it should be decomposed after its PDT activation so that it does not accumulate in the body). With these determined properties, magnesium(II), especially indium(III) acetate and zinc(II) phthalocyanines, may be suitable candidates as type II photosensitizers for photodynamic therapy applications. Lutetium(III) acetate phthalocyanine may be a photosensitizer candidate in photocatalytic applications.

Electrochemical properties of MPcs were determined with electrochemical and in-situ spectroelectrochemical measurements to investigate the influence of the metal center and the number and positions of the substituents. While H2Pc only illustrated Pc based redox processes, the incorporation of TiO2+ and Cl−1-Mn3+ cations into the cavity of Pc ring considerably altered the redox richness of the complexes. Two metal-based reduction couples were observed in addition to the Pc-based processes for both of TiOPc and MnPc. Moreover, altering the number and position of 4-(2-phenylpropan-2-yl)phenoxy substituents slightly influenced the basic redox activity of Pc ring and metal centers. All of these results supported the proposed structure of the complexes. During the redox reactions, pronounced spectral changes were observed with the in situ spectroelectrochemical measurements which caused distinct color changes. Rich redox responses and pronounced spectral and color changes of the complexes indicated their worth as functional material in various electrochemical technologies.

The most distinctive features of sound insulation structures are their flexibility and porosity. Therefore, the flexible epoxy matrix material was made cellular using a suitable foaming agent. In addition, hollow glass microspheres (HGMs) were added to the epoxy matrix. Thus, the sound wave refraction was increased by obtaining cavities in the cell walls. Structures with different densities and voids were created by changing the ratios of the filling material and foaming agents used in the sandwich. An aluminum (Al) honeycomb was used to protect the insulation materials\" structural integrity and ensure the homogeneous distribution of sound waves. The effect of density differences on sound insulation values was investigated. The mechanical properties of sandwich structures were determined using compression and three-point bending tests. The distribution of the filler in the matrix was visualized using SEM. TGA, DSC, thermal conductivity, dielectric, and flammability tests were also performed to determine their thermal, electrical, and flammability properties. During the formation of cells in the flexible epoxy, the HGMs were positioned in the cell wall by internal gas pressure. Low-density structures performed better at low frequencies, while high-density structures at high frequencies.

In recent experiments on the solidification of the binary eutectic alloy succinonitrile-(D)camphor carried out on board of the International Space Station (ISS), a transition from rod to lamellar patterns was observed for low growth velocities. The transition was interpreted in terms of a competition between a propagative instability of lamellae and a drift induced by a transverse temperature gradient. Phase-field simulations of a symmetric model alloy support this scenario: for a fixed transverse temperature gradient, the transition from rods to lamellae occurs for a critical composition at fixed velocity, and for a critical velocity at fixed composition. Since the alloy and control parameters used in experiments and simulations are different, our results strongly suggest that this morphological transition is generic for eutectic alloys.

The finite element method is the most common method used to solve engineering and mathematical model problems. Related solution areas include structural analysis, heat transfer, mass transport and electromagnetic potential. FEM is a specific numerical method used to solve partial differential equations in two or three space variables. To solve a problem, FEM breaks up a large system into smaller, simpler parts called finite elements. First, a three-dimensional model of the system to be analyzed is produced. While defining the model, the materials and connection types found in the model are also deter-mined. Afterwards, the model is divided into small parts and analyzed under specified conditions. A crash test will be conducted in this study. For this, the conditions of the vehicle parts will be examined by hitting a wall under the conditions of which the model design of the vehicle is determined. Crash tests were carried out for two different bumper thicknesses on the same vehicle and the test results were examined. The vehicle speed is modeled as 20 m/s in the simulation carried out from the moment of impact until 0.14 seconds later. The effect of buffer thickness on axial displacements at impact and energy changes are presented.

© 2023, The Minerals, Metals & Materials Society.It is becoming crucial to design/fabricate eco-friendly, sustainable electronic and photonic devices to minimize the carbon footprint for future systems. In this study, we have demonstrated a steady photoresponse enhancement of the self-powered GaN ultraviolet photodetector (GaN-UVPD) via sequentially deposited gold nanoparticles (Au NPs) under 254, 302, and 365 nm UV light exposure. The AuNP-deposited GaN-UVPD exhibited excellent responsivity of 0.65 A/W and detectivity of 6.51 × 1012 cm.Hz1/2 W−1 under 302 nm UV light without any external power. Moreover, the sensitivity of the device increased from 1.98 × 106% to 3.32 × 106% following Au nanoparticle deposition. Additionally, the plausible mechanisms for the self-powered and Au nanoparticle-induced photoresponse enhancement have been discussed. In brief, the high-performance photoresponsivity of our self-powered GaN-UVPD could find many useful applications in sustainable energy and eco-friendly optoelectronic devices.

In this study, the average power consumption of an electrode welding machine during the welding process was estimated using the features of the sound emitted during welding. First, the instantaneous values of electrode current and voltage and the sound emitted during the welding process were recorded simultaneously. The minimum, maximum, average, root mean square (RMS), and energy values of the sound data were found and feature extraction was performed, and the instantaneous power and average power values were calculated using the instantaneous current and voltage values. Three Adaptive Neuro-Fuzzy Inference Systems (ANFIS) using the sound features as inputs and average power values as outputs were created, and their results were compared. The average power values consumed during the welding process have been successfully estimated at a rate of 87-95%.

This paper presents a methodology for generating geometries for interior permanent magnet (IPM) motors in electric vehicles (EVs) through the application of artificial intelligence (AI) and image processing (IP) techniques. Due to the implementation of green agreements and policies aimed at reducing greenhouse gas emissions, EVs have become popularity. As a consequence, the improvement studies on the powertrain and battery system of EVs are focused. Especially for the powertrain, design optimization studies of e-motor have increased in the literature. One of the most widely used e-motor topologies is interior permanent magnet (IPM) motor. However, designing the IPM motor presents a challenge due to the dynamic considerations with geometric constraints. Therefore, e-motor designers encounter challenges related to determining initial geometry and the long time of the optimization process. To address these challenges, a novel approach is proposed that leverages machine learning (ML) techniques in combination with IP to generate initial geometries and design parameters for IPM motors. The proposed approach generates images of the motor geometry and extract dimensional features from the resulting images by using artificial neural networks (ANNs). The proposed method performs an analysis of the input vectors to reduce their size using techniques such as Histogram, 2D Maximum, 2D Mean, 2D Minimum, 2D Standard Deviation, and 2D Variance to enhance feature extraction. Additionally, FFT (Fast Fourier Transform) and IFFT (Inverse Fast Fourier Transform) are used to improve the neural network process in generating the image geometry. Further, the generated image geometry is improved by applying digital filtering techniques such as Log, FFT, Log+FFT, Laplacian, Sobel, and Histogram Equalization. Finally, the trained ANNs are tested to validate the results by using Ansys RMXprt and Maxwell. Eventually, the proposed method represents an innovative solution to generating initial geometries for IPM motors in EVs that satisfies desired design requirements. This approach leverages the power of AI and image processing techniques, which could lead to significant improvements in the optimization process for IPM motors, accelerate the designer’s analysis process, and enhance the performance of EVs.

In the present study, the effect of different ratios of GelMA concentration has been exhibited for wound dressing implementation by the electrospinning method using a new polymer combination of Gelatin methacrylate (GelMA)/Polycaprolactone (PCL)/Chitosan (CS). The nanofiber composites were fabricated due to their biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of GelMA were added to the PCL/CS solution as 5, 10, and 20 wt%, respectively, in the formic acid/acetic acid (7:3) solution. A photoinitiator was added to the solution for photo-crosslinking of GelMA. The influence of different solution concentrations (5, 10, and 20 wt%) on the structure’s nanofiber production and fiber morphology was examined. SEM micrographs revealed that varied GelMA concentrations resulted in suitable and stable nanofiber composites. The average diameter of nanofiber composites grows as the GelMA concentration rises. FTIR, DSC, tensile test, degradation, and swelling test were evaluated. The results demonstrated that high mechanical strength, hydrophilic properties, and a slow degradation rate were observed with the presence and increment of GelMA concentration within the nanofiber composites. The antibacterial potential of GelMA/PCL/CS nanofiber composites was evaluated against P. aeruginosa and S. aureus using a disc diffusion assay. In vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on nanofiber composites, proving these cells’ high cell proliferation rate, viability, and adhesion. 10 wt% GelMA-based nanofiber composites were found to have great potential for wound dressing applications.

Halophilic organisms are a novel attractive option as cell factories for the production of industrially valuable bioproducts. Halomonas elongata is the cell factory of choice for ectoine production, but its levan production has not been well researched. Based on this scientifc motivation, in this study, we evaluated the chemical and biological properties of levan produced by the halophilic extremophile Halomonas elongata 153B (HeL). First, the central composite design was used to determine the optimal process variables for maximum levan biosynthesis. Then, the levan produced from HeL was purifed, quantifed, and chemically characterized with FTIR, 1 H-NMR, and GPC analyses. This was followed by antioxidant, anti-infammatory, antibioflm, and antimicrobial activity tests to assess its biological activities as well as a cytotoxcity assay. Maximum levan yields of 5.13±0.38 g/L were achieved after dialysis at the optimum levels of process variables. The 1 H-NMR spectrum of HeL revealed characteristic signals. It showed a strong antioxidant activity of 67.88% and the best radical scavenger. At a concentration of 400 µg/mL, HeL showed the most anti-infammatory efcacy. Also, at all indicated concentrations (250, 500, 750, and 1000 μg/mL) HeL, acted against bioflms formed by Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 11778, Candida albicans ATCC 10231. Furthermore, HeL displayed antimicrobial activities against all strains tested. Finally, HeL showed high Cell viability in all dosages and no cytotoxicity was observed. In light of these results, HeL may have high potential in the medical, pharmaceutical and dermo-cosmetics industries.

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+ doping while minimizing the sacrificial trade-off.

Packaging must have a good commercial appearance and is generally obtained by ink transferred to its substrate. It is important that the ink used in packaging printing is produced from environmentally friendly and sustainable raw materials as well as being suitable for the printing system. The increasing demand in the field of printed packaging and the scarcity of resources to meet this demand have accelerated the search for new sources for inks. For this purpose, inks produced in the laboratory using a modified cellulose-based binder, a commercial acrylic resin and a commercial soybean protein were compared with a commercial ink. As a result of the study, it was determined that the printability properties of the ink obtained by using the modified cellulose-based binder were better than the ink obtained with commercial soybean protein. It was determined that it showed printability properties close to the ink produced with commercial acrylic binders. By using modified cellulose-based water-based flexographic ink instead of other commonly used binders, more environmentally friendly sustainable inks can be produced.

This study aims to provide a great deal of insight into how risk perception and purchase intention differ for the consumer with different online shopping motives. Data were collected through a questionnaire with 359 voluntary consumers aged 18–28 living in Istanbul. 14 motives leading them to online shopping through digital platforms for textile products were defined with the focus group technique. First, clustering analysis was conducted to define consumers according to the guiding motives in online shopping. Next, whether the consumer segments identified by these motives have different levels of risk perception and purchase intention was investigated via ANOVA analysis.

The use of bio-based building blocks for the synthesis of polymers is increasing day by day. Among the bio-based building blocks, eugenol is a highly promising monomer for the preparation of thermoset materials. In this study, we combined thiol-ene photopolymerization (TEP) and thermal azide-alkyne cycloaddition click reactions to prepare eugenol-based thermally stable, P-, N-, and Si-containing networks. To this end, we synthesized a P-containing, eugenol-based monomer bearing azide group and a siloxane compound containing an alkyne group. By mixing these monomers with multifunctional thiols and by utilizing a dual-curing strategy, we managed to obtain optically transparent and thermally stable coatings with excellent adhesion to glass substrates. Thermal stability, optical transmittance, pendulum hardness, solvent resistance, and the adhesion performance of the coatings were evaluated. The gel contents of the thermoset materials were found to be over 95%. At 600 °C, the char yields of the dual-cured coatings were found to be over 30%. Coatings were also found to be resistant to acidic and basic conditions as well as solvents.

Bu çalışmada, farklı oranlarda %3yttria stabilize zirkonyum oksit (ZrO2) ilavesinin atık koyun femur kemiklerinden elde edilmiş olan hidroksiapatite (KHA) etkisi incelenmiştir. Bu amaçla 4 farklı kompozit hazırlandı ve preslendikten sonra 1100-1300oC arasında 4 saat süre ile sinterlendi. Saf koyun hidroksiapatit için artan sinterleme sıcaklıkları ile yoğunluk, kısmi yoğunluk, sertlik ve kırılganlık indeksi artarken, en yüksek yatay (8.23±0.28 MPa) ve dikey basma (82.48±5.50 MPa) mukavemeti ve kırılma tokluğu (0.70±0.11 MPam1/2) 1200oC’ de elde edildi. Saf KHA’ in 1300oC’ de sinterlenmesi beta trikalsiyum fosfat (β-TCP), alfa trikalsiyum fosfat (α-TCP) ve kalsiyum oksit (CaO) fazlarına dekompoze olmasına neden olmuştur. Bu sıcaklık için saf KHA’ daki dekompoze olma oranı %4.1 olarak hesaplandı. KHA-ZrO2 kompozitlerinde dekompoze olma oranı, artan sinterleme sıcaklığı ve ZrO2 oranı ile %48.1’ e kadar artmıştır. KHA-ZrO2 kompozitlerinde iki farklı kalsiyum zirkonat (CaZr4O9 ve CaZrO3) fazı dedekte edilmiş olup, bu kompozitlerde dekompozisazyonun artışının CaZrO3 fazından kaynaklandığı kanaatine varılmıştır. 1200oC’ de sinterlenen KHA-2.5ZrO2 kompozitinin KHA-ZrO2 kompozitleri içerisinde en iyi özelliklere sahip olduğu belirlendi. Bu kompozitin kırılma tokluğu 1.25±0.08 MPam1/2, dikey ve yatay basma mukavemeti değerleri ise 122.0±2.12 MPa ve 11.21±0.42 MPa’ dır. Ancak; KHA-ZrO2 kompozitinin yetersiz kırılma tokluğu özelliği nedeniyle insan vücudunda yüke dayanım gerektirmeyen uygulamalarda kullanılması önerilmektedir.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which emerged in 2019, cut the epoch that will make profound fluctuates in the history of the world in social, economic, and scientific fields. Urgent needs in public health have brought with them innovative approaches, including diagnosis, prevention, and treatment. To exceed the coronavirus disease 2019 (COVID-19) pandemic, various scientific authorities in the world have procreated advances in real time polymerase chain reaction (RT-PCR) based diagnostic tests, rapid diagnostic kits, the development of vaccines for immunization, and the purposing pharmaceuticals for treatment. Diagnosis, treatment, and immunization approaches put forward by scientific communities are cross-fed from the accrued knowledge of multidisciplinary sciences in health biotechnology. So much so that the pandemic, urgently prioritized in the world, is not only viral infections but also has been the pulsion in the development of novel approaches in many fields such as diagnosis, treatment, translational medicine, virology, microbiology, immunology, functional nano- and bio-materials, bioinformatics, molecular biology, genetics, tissue engineering, biomedical devices, and artificial intelligence technologies. In this review, the effects of the COVID-19 pandemic on the development of various scientific areas of health biotechnology are discussed.

Recently, there has been an increasing interest in environmentally friendly methods for the removal of toxic dyes to enable sustainable textile dyeing processes. In this study, a highly efficient, non-toxic, low-cost MgO particles were prepared by sol-gel technique and utilized for the removal of Reactive Red 21 azo dye by adsorption process. The prepared MgO particles were characterized by Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, and Particle Size Analysis. The batch adsorption studies were performed for optimizing the parameters affecting adsorption. The adsorption behavior of Reactive Red 21 was accurately characterized by the Langmuir model. The adsorption process was found to be thermodynamically spontaneous at room temperatures as indicated by the negative Gibbs free energy change (∆G) value of −30.65 kj/mol. The kinetic studies indicate that the pseudo-second-order model provides a good fit to the adsorption of Reactive Red 21. The adsorption capacity of the prepared MgO particles for Reactive Red 21 was determined to be 355 mg/g at room temperature over a wide pH range of 5–9, with a contact time of 20 min. The regeneration of dye-adsorbed MgO particles was conducted at 500 °C for 2 h. The regenerated MgO particles were then utilized for adsorbing Reactive Red 21 five times with a sufficiently high dye removal efficiency. The prepared MgO particles provided a 98 % dye removal in real textile wastewater containing Reactive Red 21 dye.

The main outdoor factors that reduce the efficiency of the photovoltaic (PV) panel are the reflection and refraction of light, dirt, dust, and organic waste accumulating on the panel surface. In this article, an antireflection, self-cleaning coating was applied on the PV panel cover glass with a new method. With the coating, the surface has been given a hydrophobic feature. As a coating method, a 3-D printer has not been seen in the literature and used as a new method. The electrospinning method has also been tried as an alternative method. Solutions in different combinations were developed using polylactic acid or polymethylmethacrylate polymer, chloroform ($\text{CHCl}_3$) as a solvent, and silicon dioxide ($\text{SiO}_2$) and titanium dioxide ($\text{TiO}_2$) nanoparticles as primary materials in a modified 3-D printer for bioprinting. Five PV panels were obtained by applying different 3-D parameters from three solutions, which have the best results. Coating thicknesses are in the range of 3.12-8.47 mu m. Coated and uncoated PV panels were tested in outdoor conditions for ten-day periods. The power outputs of the PV panels were measured, and their ten-day average efficiency was presented. According to the results, the highest efficiency increase is 8.7%. The highest light transmittance is 88.2% at 550 nm. In addition, hydrophobic properties were observed on all surfaces and the water contact angle was measured as 96.18 degrees.

In this study, with the help of the known effect of Fe2O3, which is a sintering aid additive for sintering, it is possible to synthesize products at temperatures much lower than 1500°C, which is the known sintering temperature in the phase diagram of the mullite-zircon system. In addition to the phase and microstructure analysis of the produced products as a result of the addition of sintering aid additive (Fe2O3) and reaction sintering process, mechanical characterizations were performed. The sintering aid additive (Fe2O3) was mixed into the Mullite-Zircon structure by adding 1 wt.%, 2 wt.% and 3 wt.%. 1% by weight of PAN was used as the binder. This mixture was formed into pellets before sintering under the selected pressing force of 2500 psi. These pellets were sintered at 1500°C, 1450°C, and 1400°C sintering temperatures, respectively, with a sintering time of 5 hours for each temperature. As a result of these processes, the effect of sintering temperature and the effect of the amount of sintering aid additives were examined by using characterization methods. It was aimed to determine the optimum parameters for this material, considering the important properties of ceramics such as porosity, hardness, density, and microstructure of the product to be produced with these additives and parameters. X-Ray Diffraction analyses were performed, and the phases formed as a result of the reaction were determined. Microstructure analyses were made for sintering temperatures of 1500°C, 1450°C, and 1400°C using an optical microscope. The optimum sintering temperature for the parameters used in this study and the amount by weight of the sintering aid additive to be used were selected considering variable factors in this study, and it was aimed to find the product with the best properties and the lowest cost.

Cellulose is an important raw material in the manufacture of paper. Cellulose is formed by thefelting, fringing, swelling by absorbing water of the fibers and the combination of these fibersas a result of certain processes. Paper is also obtained by processing plant fibers. It is alsopossible to reuse the waste paper, which are completed in utilization, in paper production byrecovering the cellulose in its structure. Recycling is the process of transforming these wastepapers, which can be reused, into a second raw material by subjecting them to physical orchemical processes. In addition to being sustainable, significant savings are achieved in theamount of raw materials used in paper recycling. In addition, this saving is economicallybeneficial to production due to the high cost of raw materials.In this study, natural dye plants and natural dyeing methods were used to produce paper fromrecycled cellulose with the aim of increasing sustainability. In order to prevent the negativitiesoriginating from the increase in carbon emissions that synthetic dyes cause, it is aimed toincrease the use of natural dyeing methods in paper production. Since natural dye plants areproduced from plant itself or its waste, they do not cause environmental pollution and provideadvantages for recycling.In this study, cellulose fibers were colored with natural dyeing method using walnut shell.Thus, between the fibers, samples colored with walnut shells and samples that were notcolored were examined under two different conditions. Samples were prepared in twodifferent ponds, 5 L and 8 L, with a fixed ratio of solids. Paper sheets were formed with thesieve using the dipping method in the prepared concentration and at the same time, thetechnical properties of the samples were examined by reducing the fibers at a certain rate.Samples were measured in terms of weight, color measurement, light fastness, contact angle,surface smoothness, air permeability and compared with the data obtained.Keywords: Waste paper, Recycling, Natural dyeing, Sustainability Kağıdı imalatında önemli bir yere sahip hammadde selülozdur. Selüloz, liflerin keçeleşmesi, saçaklanması, su emerek şişmesi ve belirli işlemlerden geçmesi sonucunda bu liflerin birleşmesiyle oluşmaktadır. Bitkisel liflerin işlenmesiyle de kağıt elde edilmektedir. Kullanımı tamamlanmış atık durumunda olan kağıtların, yapısındaki selülozun geri kazanılmasıyla tekrardan kağıt üretiminde kullanılabilmesi de mümkündür. Yeniden değerlendirilme imkanı olan bu atık kağıtların fiziksel veya kimyasal işlemlere tabi tutularak ikinci bir hammaddeye dönüştürülmesine geri dönüşüm denmektedir. Sürdürülebilir olmasının yanında kağıt geri dönüşümünde kullanılan hammadde miktarında önemli oranda tasarruf sağlanmaktadır. Ayrıca yapılan bu tasarruf hammaddenin pahalı olmasından dolayı ekonomik açıdan üretime fayda sağlamaktadır. Bu çalışmada sürdürülebilirliği arttırmak amacıyla geri dönüştürülen selülozlardan kağıt üretimi yaparken doğal boya bitkileri ve doğal boyama yöntemleri kullanılmıştır. Sentetik boyaların karbon salınımını arttırmasından kaynaklı olumsuzlukları engellemek için doğal boyama yöntemi tercih edilerek kağıt üretiminde kullanımını arttırmak amaçlanmaktadır. Doğal boya bitkileri kendilerinden veya atıklarından üretildiği için çevre kirliliği oluşturmamakta ve geri dönüşüm için avantaj sağlamaktadır. Yapılan bu çalışmada selüloz lifleri ceviz kabuğu kullanılarak doğal boyama yöntemi ile renklendirilmiştir. Böylece lifler arasında ceviz kabuğu ile renklendirilen numuneler ve renklendirilmeyen numuneler olarak iki farklı koşulda incelenmiştir. Numuneler iki farklı havuz içerisinde 5 L ve 8 L olarak ve belirlenen sabit oranlarda katı madde oranıyla hazırlanmıştır. Hazırlanan konsantrasyon içerisine daldırma yöntemi kullanılan elek ile kağıt sahifeleri oluşturulmuş ve aynı zamanda numuneler belirli oranda lifleri azaltılarak teknik özellikleri incelenmiştir. Numuneler; gramaj, renk ölçümü, ışık haslığı, kontak açısı, yüzey düzgünlüğü, hava geçirgenliği bakımından ölçülüp çıkan veriler ile karşılaştırılmıştır. Anahtar kelimeler: Atık kağıt, Geri dönüşüm, Doğal boyama, Sürdürülebilirlik

This work evaluates the effects of manganese (Mn) doping on the morpho-structural features, mechanical performance, and in vitro biological response of beta-tricalcium phosphate (β-TCP) derived bioceramics for bone tissue engineering applications. Five different Mn doping levels (i.e., 0.01%, 0.05%, 0.1%, 0.5%, and 1 wt.%) were investigated, with the β-TCP-based bioceramics being sintered at four temperatures (i.e., 1000, 1100, 1200, and 1300 °C). A densification improvement was induced when using Mn in excess of 0.05 wt.%; the densification remained stationary in the sintering temperature range of 1200 − 1300 °C. The structural analyses evidenced that all samples sintered at 1000 and 1100 °C were composed of β-TCP as major phase and hydroxyapatite (HA) as a minor constituent (~ 4–6 wt.%). At the higher temperatures (1200 and 1300 °C), the formation of α-TCP was signalled at the expense of both β-TCP and HA. The Mn doping was evidenced by lattice parameters changes. The evolution of the phase weights is linked to a complex inter-play between the capacity of the compounds to incorporate Mn and the thermal decomposition kinetics. The Mn doping induced a reduction in the mechanical performance (in terms of compressive strength, Vickers hardness and elastic modulus) of the β-TCP-based ceramics. The metabolic activity and viability of osteoblastic cells (MC3T3-E1) for the ceramics were studied in both powder and compacted pellet form. Ceramics with Mn doping levels lower than 0.1 wt.% yielded a more favorable microenvironment for the osteoblast cells with respect to the undoped β-TCP. No cytotoxic effects were recorded up to 21 days. The Mn-doped β-TCPs showed a significant increase (p < 0.01) in alkaline phosphatase activity with respect to pure β-TCP.

Low-cost zirconia-toughened mullite composites were prepared from investment casting shell waste and alumina. The influence of sintering temperature on the composites\" properties, including crystalline phase composition, microstructure, degrees of densification, mechanical properties, and radiation shielding characteristics, was investigated. The results show that the higher the sintering temperature, the higher the degree of densification is, improving the mechanical and radiation shielding properties of prepared composites. The mullite-zirconia composite sintered at 1600 °C presents a good mechanical strength, with flexural and compressive strength values of 190 and 308 MPa, respectively. These values are comparable to or even better than mullite ceramics prepared from other waste materials. Furthermore, the composites\" gamma-ray and neutron attenuation characteristics suggest that they can be promising as radiation shields.

Brass alloys assign a considerable portion of the industrial components\" material due to their outstanding characteristics. These materials are manufactured using hot forging or extrusion techniques, according to the application for different purposes. In this work, the metallographic and mechanical characteristics of three environmentally friendly brass alloys - CuZn40Pb2 (CW617N), CuZn38As (CW511L) and CuZn21Si3P (CW724R) - extruded and multi-directionally hot forged have been examined. By focusing on the flat bottom drilling operation, the effects of the process and type of alloying have been investigated. The examination has been accomplished on experimental data about tensile strength, impact fracture energy, cutting forces, entrance and exit burr diameters, as well as hole quality. The findings demonstrate that the most crucial criteria impacting the machining outcomes are the presence of limited Pb element and material microstructural phases, their content and mechanical characteristics, as well as the type manufacturing process.

Lower limb rehabilitation robots (lower back exoskeleton) are one of the robotics fields where research is still ongoing to find solutions to the problems of paralysis and movement restriction caused after an accident as a result of various reasons. Hemiplegia, commonly known as stroke, causes loss of movement or restriction of movement in patients with the right and left parts of the body being affected as a result of blockage in the cerebral vessels. Physical therapy and rehabilitation are very important in such disease situations. For hemiplegic patients, the rehabilitation applications applied include exercises for strengthening of muscles, occupational therapy, treatment determined according to the patient, such as hip and knee joints, physical therapy such as exercise methods and speech therapy, rehabilitation methods and devices used in applications. When evaluated from this point of view, it is important to use walking robots in the treatment methods we mentioned above. In this thesis project, Walking robot (Rehabilitation Robot or Exoskeleton Robot) is used for individuals with congenital joint disorders, for individuals with disabilities, for individuals who have difficulty in movement and walking as a result of subsequent hemiplegia, fall, slip, injury, for occupational diseases related to lower extremities in workers working in the business sector, for individuals with lower skeletal system in the construction industry, paint industry and heavy-work industry. It is a robot model that can also be used for occupational diseases related to lower extremities in workers working in the business sector, for individuals with lower skeletal system disorders due to natural disasters such as work accidents and earthquakes, and for individuals with walking and movement restrictions. For this reason, walking robot (Rehabilitation Robot or Exoskeleton Robot) will be studied in the research. By creating walking robot design, simulation and prototype, it is aimed to create products and be useful to the sector.

In this study, the 3 dimensional description of the quaternary subsolidus slag system alumina-silica-calcia-magnesia is evaluated using Mathematica programming based on previous experimental research data. The lever rule in the tetrahedra is then applied for a given arbitrary liquid composition A% + %B + %C + %D = 100 in order to calculate the solid phases present (neglecting solid solutions) with their relative proportions after the solidification is completed. A novel transformation and algorithm are then developed using simple geometry and MathLab programming which can also be used for other subsolidus systems in case appropriate data are provided.

The adverse health and environmental effects of petroleum-based materials have become a driving force for the fabrication of bio-based monomers. In this study, we synthesized a novel bio-based reactive phosphorus-containing; eugenol-DOPO, which was prepared in one step by the reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and eugenol via Atherton–Todd reaction. Moreover, a diallyl compound was also prepared by using eugenol and piperazine. All monomers were characterized by nuclear magnetic resonance (NMR), mass, and Fourier-transform infrared (FTIR) spectroscopies. Thiol-ene photocured polysulfide thermoset networks were prepared by using these newly synthesized bio-based monomers. Thermal and thermomechanical properties of the thermosets were measured. Photo-crosslinked networks displayed over 88% gel content values. The thermal stability of the networks as well as the resulting char yields were improved as the percentage of eugenol-DOPO was increased in the formulations. The presence of N and P played a synergistic effect and the limiting oxygen index (LOI) values for the thermoset materials were enhanced. We believe eugenol-DOPO is not only a good alternative monomer for the preparation of thermally stable photocurable thermosets, but it is also a suitable bio-based additive for other polymers as well. Graphical Abstract: [Figure not available: see fulltext.].

In the present study, the potential of barium zirconate (BaZrO3; 1-5 wt. %) on the sinterability, and properties of bovine hydroxyapatite (BHA) was evaluated. BHA decomposed into beta and alpha-tricalcium phosphate (beta and alpha-TCP) at a 4.7 % rate. Tetracalcium phosphate (TTCP) was detected as the decomposition phase in the BaZrO3 added BHAs, and it increased up to 10.7 % with an increasing BaZrO3 ratio. In addition to TTCP, the phases of BaZrO3, Ba2ZrO4, sigma-Ba2P2O7, Ba3P2O8 and CaZrO3 were detected in the composites. The addition of BaZrO3 at an amount of 3 wt. % has a higher potential than the others to improve the sinterability and properties of BHA. It contributed to the increase in the fracture toughness from 0.99 +/- 0.13 to 1.80 +/- 0.12 MPa center dot m1/2 and the compressive strength from 115.75 +/- 4.27 to 173.66 +/- 13.61 MPa, and the de-crease in the brittleness index from 4.24 +/- 0.31 to 2.45 +/- 0.15 mu-1/2. The in-vitro bioactivity of BHA also increases with the additional BaZrO3. However; it is recommended to be used in applications that do not require load bearing in the human body due to its insufficient fracture toughness.

Less energy consumption and more efficient use of renewables are among the sustainable energy targets of modern societies. The essential activities to be achieved under these objectives are to increase distributed generation (DG) structures’ applicability. DG systems are small-scale versions of the traditional power grid; they are supported by micro turbines, photovoltaics (PV) modules, hydrogen fuel cells, wind turbines, combined heat and power systems, and energy storage units. The aim of this research is to detail the performance analysis of a proton-exchange membrane fuel cell (PEMFC)-based grid-connected distributed generation system with the help of empirical calculations. To this end, we aimed to establish the system and analyze the performance of the reliable operation of the system with experimental verifications. The findings demonstrate how much power can be generated annually, through real meteorological data, to dispatch to constantly variable loads. While 53.56% of the total energy demand is met by the utility grid, 46.44% of the demand is met by the produced energy i.e., from the DG. The PEMFC-based DG system analyzed in detail in this study was located at Marmara University. According to the results of the performance analysis, significant points of this study will be highlighted to assist the researchers working in this field. Our results are encouraging and can be certified by a larger sample size with neat weather conditions in terms of the percentage of procurement of energy.

© 2022 Elsevier B.V.Novel CoPc, CuPc, Fe(OAc)Pc and Mn(Cl)Pc were synthesized by using original 4-chloro-5-(2-isopropyl-5-methylphenoxy)phthalonitrile in order to investigate their potential redox applications suitable with their chemical and physical characteristics. The molecular structures of new compounds were determined with spectroscopic methods such as elemental analysis, FT-IR, UV–vis, NMR and MALDI TOF MS. Redox behaviours of Fe(OAc)Pc and Mn(Cl)Pc complexes have been probed by using diverse voltammetric techniques such as cyclic (CV) and square wave voltammetry (SWV). In addition, the colour alterations accompanying spectral changes were perused concurrently with electrocolorimetric measurements, and electrocatalytic efficiencies of the all compounds were perused in oxygen reduction reaction.

© 2023 Acta Materialia Inc.The microneedle (MN) technology platform has a significant potential for enhancing the efficacy of transdermal drug delivery, by using micron-scale arrays with restricted geometries that pierce the skin non-invasively. In this paper, we developed gelatin methacryloyl (GelMA) MNs containing amoxicillin (AMX) as a novel transdermal delivery system using digital light processing (DLP) based 3D printing technology. With the DLP approach, MNs were obtained with high resolution and minimal lead times without geometric limitations. The 3D-printed AMX-loaded GelMA MNs were examined for their morphological, mechanical, swelling and antimicrobial properties as well as the drug release profile. The morphological analysis demonstrated the successful fabrication of the MNs with regular structure and sharp tips. The fabricated MNs displayed good mechanical properties consistent with 0.1 N/needle without breaking. Moreover, the results of the in vitro antibacterial activity assays indicated that AMX-loaded GelMA MNs have significantly inhibited the Staphylococcus aureus and Escherichia coli growth. These findings suggest that the 3D-printed drug-loaded GelMA MNs are a useful platform for transdermal therapeutic delivery and can be developed as a next-generation medical device for managing bacterial infections.

In this experimental research; It has been studied to improve the properties of polypropylene grape stalk and paddy mixtures by adding waste glass fiber. The potential of waste grape stalk and paddy to be a reusable material has created another curious subject. Polypropylene grape stalk and paddy were mixed in a twin screw extruder to provide a homogeneous mixture. Paddy; It is known as rice husk. Grape stalk-paddy was added to the PP at the rate of 20%. Glass fiber was added at 10-15% and 20% rates. Then the test samples were molded on the injection machine. Molded samples; Tensile, hardness, impact, density and scanning electron microscopy tests were performed. By examining the results of the tests, the effects of grape stalk-paddy and glass fiber amount on polypropylene were determined. Bu deneysel araştırmada; polipropilen (PP) üzüm sapı ve çeltik karışımlarının özelliklerinin atık cam elyaf ilavesi ile geliştirilmesi üzerine çalışılmıştır. Atık olan üzüm sapı ve çeltiğin yeniden kullanılabilir bir malzeme olma potansiyeli diğer merak edilen bir konuyu oluşturmuştur. Polipropilen üzüm sapı ve çeltik çift vidalı ekstrüderde homojen bir karışım sağlamak için karıştırılmıştır. Çeltik; pirinç kabuğu olarak bilinmektedir. PP içerisine %20 oranında üzüm sapı-çeltik katılmıştır. Cam elyaf ise %10-15 ve 20 oranlarında katılmıştır. Daha sonra enjeksiyon makinesinde test numuneleri basılmıştır. Kalıplanan numunelere; çekme, sertlik, darbe, yoğunluk ve taramalı elektron mikroskobisi testleri yapılmıştır. Testlerin sonuçları incelenerek üzüm sapı-çeltik ve cam elyaf miktarının polipropilen üzerindeki etkileri belirlenmiştir.

We report the magnetic properties of LaFe2As2, La0.8Ba0.2Fe2As2, and La1-xBaxPt0.1Fe1.9As2 (0

Due to its economic worth, cotton (Gossypium hirsutum L.) is grown in almost 70 countries and provides income for more than 250 million people. Therefore, producing cotton with having some desired characteristics that includes extended biotic and abiotic stress tolerance, improved fiber quality, promoted nutritional content and increased yield is the main objective for cotton biotechnology. To achieve this goal, many tissue culture and gene transfer techniques are being developed and used throughout the years. As applications for the gene transfer, the Agrobacterium-mediated, particle bombardment and pollen tube pathway-mediated methods are most successfully used and in conjunction with this, meristematic shoot tips as explants are efficiently utilized in gene transfer methods. In this study, the main objective was to report an efficient protocol for a greater recovery of transgenic cotton plant using Agrobacterium tumefaciens-mediated transformation. For this, one of the cotton strains (Cukurova 1518) cultivated widely in Turkey was chosen and meristematic shoot tips as explant sources, and GFP and NPTII genes as reporter and marker genes were used, respectively. The effective post co-cultivation conditions were provided via using the selection regime in vitro. Finally, the current results showed highly reproducible protocol developed could be used to produce transgenic cotton plants expressing desired traits or can be utilized as a model system to study the expression of particular genes. 由于其经济价值, 棉花 (Gossypium hirsutum L.) 在近70个国家种植, 为2.5亿 多人提供收入. 因此, 棉花生物技术的主要目标是生产具有某些期望特性的 棉花, 包括延长生物和非生物胁迫耐受性、改善纤维品质、提高营养含量 和增加产量. 为了实现这一目标, 多年来, 许多组织培养和基因转移技术被 开发和使用. 作为基因转移的应用, 农杆菌介导、粒子轰击和花粉管通道介 导的方法被最成功地使用, 与此相结合, 分生茎尖作为外植体被有效地用于 基因转移方法. 在这项研究中, 主要目的是报告一种利用根癌农杆菌介导的 转化更有效地恢复转基因棉花植株的方案. 为此, 选择在土耳其广泛种植的 棉花品系之- (Cukurova 1518), 分生茎尖作为外植体来源, GFP和NPTII基因分 别作为报告基因和标记基因. 通过体外筛选机制提供了有效的共培养后条 件. 最后, 目前的结果表明, 所开发的高重复性方案可用于生产表达所需性 状的转基因棉花植株, 或用作研究特定基因表达的模型系统.

The production of porous ceramics for biomedical applications is widely available in the Ceramics industry. In bioceramic applications, interconnected pores are pertinent to increase osteoconductivity and cell proliferation. However, an increase in pore size and the pore amount decrease the mechanical properties. For this reason, pore properties must be precisely controlled. In this study, the effect of a natural pore-forming agent, corn starch addition, and sintering conditions on mechanical properties and biocompatibility was investigated. During mixing, four different starch amounts (1, 3, 5, and 10 wt%) were added to pure beta-tricalcium phosphate (β-TCP) ceramic powders and pressed. Pressed pellets were sintered at 1000, 1100, 1200, and 1300 °C. A scanning electron microscope (SEM) is used to investigate microstructure, texture, pore size, and cell adhesion. The mechanical properties of the β-TCP ceramic parts were further characterized by measuring the density and compressive strength. Cytotoxicity tests were carried out with MTT assays. The optimum mechanical properties were obtained at 1100 °C sintered biocomposites. Although starch starts to burn around 410 °C and analytical results show no presence of starch after the sintering process, biocomposites initially containing 10% starch showed improved cell proliferation. However, a reduction of 59% in compressive strength and a 16% reduction in the density were also recorded. It was observed that 10 wt% starch addition increases cell proliferation by 10% in sintered β-TCP samples. Starch powder additions can be used to increase the cell viability of the material by facilitating the creation of pores, as a low-cost pore-forming agent for porous bone graft and non-load-bearing material in both orthopaedics and maxillofacial applications. Graphical abstract: [Figure not available: see fulltext.]

This study compares the cementation performance of metallic iron, metallic aluminum, and metallic tin in terms of the reaction conditions and parameters in synthetic antimony chloride solutions. The effects on the antimony recovery (%) caused by the cementators\" types, stirring speed, reaction time, and temperatures were explored thoroughly. The cementation kinetics of antimony were also explored for each cementator. The activation energies were determined to be 10.99, 9.09, and 13.58 kJ mol(-1) for Al, Fe, and Sn, respectively. The results reveal that the reaction is diffusion controlled, and comparable results were obtained for each cementator. At 25 degrees C, 40 mg of iron powder was found to reduce all antimony ions (i.e., approx. 99% recovery), but even when 100 mg of Al and Sn cementators were used, the antimony recovery did not reach 100%. This result shows that iron is the best candidate to cement antimony out of the solution.

This work was supported in part by IHS Kurumsal Teknoloji A.S., and in part by the Tuerkiye Bilimsel ve Teknik Arastirma Kurumu(TUBITAK) under Grant 115E389 User Provided Network (UPN) is a promising solution for sharing the limited network resources by utilizing user capabilities as a part of the communication infrastructure. In UPNs, it is an important problem to decide how to share the resources among multiple clients in decentralized manner. Motivated by this problem, we introduce a new class of games termed distribution games that can be used to distribute efficiently and fairly the bandwidth capacity among users. We show that every distribution game has at least one pure strategy Nash equilibrium (NE) and any best response dynamics always converges to such an equilibrium. We consider social welfare functions that are weighted sums of bandwidths allocated to clients. We present tight upper bounds for the price of anarchy and price of stability of these games provided that they satisfy some reasonable assumptions. We define two specific practical instances of distribution games that fit these assumptions. We conduct experiments on one of these instances and demonstrate that in most of the settings the social welfare obtained by the best response dynamics is very close to the optimum. Simulations show that this game also leads to a fair distribution of the bandwidth. IHS Kurumsal Teknoloji A.Ş Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK) Publisher's Version Q2 WOS:000892934100001

The textile industry is one of the most complex sectors, in terms of the materials and chemical processes used from petroleum and the environmental degradation during its production and disposal. It is therefore a sector looking for new possibilities and for more sustainable materials and applications. One option is to use natural dyes, as they are considered biodegradable, do not pollute the environment, and have potential use for many sectors, including the fashion industry. In this study, Alanya silk was dyed by a natural dyeing method with crocus sativus, Helichrysum arenarium, and Glycyrrhiza glabra L., plants that grow in and around the Alanya region. Quercus aegilops L. grown in the region was preferred as mordant, a natural binder, and is one of the plants with the highest tannin content, and it was used with a more environmentally friendly and sustainable approach to increase the binding in natural dyeing instead of chemical mordants. The aim is to provide an environmental and scientific contribution to the dyeing producers in this region. According to the MAUT (Multi-Attribute Utility Theory) method, the best dyes in terms of fastness and color efficiency were determined as the dyes made with the Glycyrrhiza glabra L. plant.

© 2023 The Author(s). Published with license by Taylor & Francis Group, LLC.Biocomposites are a strong alternative to synthetic fiber-reinforced composites due to their environmentally friendly nature, ease of availability, cost-effectiveness, and non-toxicity. Felt biocomposites are generally favored for their better sound and temperature absorption capabilities rather than load-bearing materials due to their comparatively weak mechanical properties. However, their mechanical performance is greatly improved when they are fabricated as plates using traditional techniques like compression molding. This study focuses on the mechanical characterization and comparison of different types of hot-pressed felt biocomposite plates with a 50% by weight natural fiber content. Four unique biocomposite felts were produced and subjected to tensile, compressive, shear, instrumented Charpy v-notched impact, and drop weight impact tests. All felt kinds are reinforced with short hemp fibers and four distinct polymers are used as matrix materials, namely, polypropylene, recycled polypropylene, polylactic acid, and low-melt polyester fiber. Static and impact tests performed on those materials revealed that each type of natural fiber felt biocomposite has its unique features, and their characterized static and impact behaviors vary significantly from one to another. Therefore, each can be an appropriate material choice in an engineering design. 生物复合材料是合成纤维增强复合材料的有力替代品, 因为其环保性、易 获得性、成本效益和无毒性. 毛毡生物复合材料由于其相对较弱的机械性 能, 通常因其更好的声音和温度吸收能力而非承重材料而受到青睐. 然而, 当它们使用传统技术（如压缩成型）制成板材时, 它们的机械性能会大大 提高. 本研究侧重于具有50重量%天然纤维含量的不同类型热压毡生物复 合材料板的机械特性和比较. 生产了四种独特的生物复合毡, 并进行了拉 伸、压缩、剪切、仪表化夏比v形缺口冲击和落锤冲击试验.所有类型的毛 毡都用短大麻纤维增强, 四种不同的聚合物用作基质材料, 即聚丙烯、再生 聚丙烯、聚乳酸和低熔点聚酯纤维. 对这些材料进行的静态和冲击试验表 明, 每种类型的天然纤维毡生物复合材料都有其独特的特征, 它们的特征静 态和冲击行为各不相同. 因此, 在工程设计中, 每种材料都可以是适当的材 料选择

Corneal ulcer, which is brought on by a breach in the epithelial barrier, is a dangerous infection of the avascular corneal stroma. New treatment strategies are needed, suppressing the aggressive nature of the disease and including a combination of different drugs. In this study, vancomycin (VAN) and fluconazole (FLU) dual-drug loaded dual-layered polyvinyl alcohol and gelatin (PVA/GEL) nanofibrous patches are produced by electrospinning. Scanning electron microscopy (SEM) images show smooth surfaces are obtained for both pure and drug-loaded nanofibrous patches. The tensile test results report that loading the FLU and VAN separately into the PVA/GEL patches decrease both the tensile strength and elongation at break and it is further reduced when combining two drug-loaded layers in one patch. According to drug release results, the FLU and VAN-loaded nanofibrous patches show a controlled release profile extending up to 96 h. Moreover, PVA/GEL/FLU, PVA/GEL/VAN, and PVA/GEL/FLU/VAN nanofibrous patches display significant antimicrobial activity against Candida albicans and Staphylococcus aureus. SEM, 4\"-6diamidynofenyloindol (DAPI) staining, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay show that PVA/FLU and PVA/GEL/FLU/VAN nanofibrous patches have a superior effect on NIH3T3 cell spreading and proliferation. The novelty of this study lays in the development of a potential dual drug rapid treatment for corneal ulcers of aggressive nature.

Additive manufacturing has many techniques and has been frequently used and studied recently. The fused deposition modeling (FDM) method, which is one of these techniques, is a widely used three-dimensional (3D) printing method that works with the extrusion principle. The parameters used during printing affect the properties of the final product. This study investigated the effect of print angle, infill density, and perimeter count parameters on the tensile strength characteristics of FDM-printed PLA samples by the response surface method (RSM), an experimental design method. The tensile strengths of the samples produced according to the test lists obtained using the Box–Behnken design were determined. A model equation showing the effect of the relevant parameters was created. From the experiments, the compatibility of the model equation with the experimental results has been demonstrated. The highest tensile strength values were achieved in cases where the print angle was 90°, the infill density was 100%, and the number of walls was 5-6.

Currently, it is important to manufacture fiber-reinforced epoxy matrix composites with high impact resistance besides their high strength and modulus values for industries such as automotive, aerospace, and aviation due to the brittle structure of epoxy. In this regard, we found the attractive results of the 0.5 wt% poly(vinyl butyral) (PVB)-containing epoxy blend in terms of strength, Young\"s modulus, and impact resistance. These results substantially motivated us to manufacture fiber-reinforced advanced epoxy/PVB matrix composites with 30–60 vol% carbon-aramid fiber ratios. Flexural (three-point bending) and tensile tests were performed to obtain strength and modulus values by measuring the force required to break the fiber-reinforced composite specimens and elongation at break points. Interlaminar shear strength tests were performed by the short beam bending method by measuring the resistance of the composite to delamination. The Charpy impact test was used to measure the energy absorbed during crack formation and fracture propagation. The composites with PVB were generally superior to those without PVB (EPCs). Two types of findings were observed. First, PVB increased the tensile and flexural strength values substantially for the 30 and 40 vol% ratios, but the modulus values slightly decreased. Second, PVB also substantially increased the modulus values for the 50 vol% ratio besides the strength values. It was thought that this result could be attributed to the increase in the compatibility of the fiber/matrix for the 50 vol% ratio. These decreases for EPCs could be derived from the micro-cracks and weaker interface between fiber and matrix.