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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.

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.

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.

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.

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.

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.

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.

© 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.

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

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.

The design of scaffolds for controlled drug release in bone tissue engineering requires careful consideration of several factors. Scaffold degradation and drug diffusion within the polymer matrix, influenced by pore size and distribution, must be carefully considered in the design of composite scaffolds. In this study, multi-functional scaffolds containing different amounts of hydroxyapatite (0, 0.25, 0.5, 1 % wt/wt) were prepared and characterised in terms of their chemical and morphological properties, as well as their drug release capabilities. Amoxicillin was used as a model drug to investigate the kinetic release model of the scaffolds, which were created using a freeze-dry method to form a spongy structure. Image processing techniques were used to measure the surface pore sizes and distributions. The results showed that the 0.5 wt. % hydroxyapatite-added scaffold had the smallest size, with an average pore size of 7 +/- 4.3 mu m and a weight loss of 45 %. All the prepared scaffolds fit Hills kinetic model. The best fitting one was observed in the 0.5 wt. % addition. By carefully considering all the factors, it is possible to optimise the release of the drug from the polymeric material and the degradation characteristics to improve its performance.

This study presents a comprehensive investigation of ferroresonance, a dangerous electrical phenomenon that poses significant financial risks. Using real electrical transmission line parameters, we simulated synthetic ferroresonance scenarios on a model and analyzed the resulting data using high-order spectral analysis methods, including the Wigner-Ville method, Welch method, frequency-power analysis, and spectral methods. Our analysis revealed changes in frequency and power before and after ferroresonance, with third and fourth-order cumulants being calculated. We confirmed the accuracy of the power transmission line’s base frequency and power before the ferroresonance event and determined the frequency and power values before and after ferroresonance with frequency-power analysis. Our cumulative analysis results showed symmetrical results that are consistent with the properties of ferroresonance. Additionally, we found that the Wigner Ville method’s high-resolution results were significantly more effective than conventional methods. Our study’s findings provide valuable insights into ferroresonance’s behavior and may inform the development of more effective prevention and mitigation strategies.

In this study, the nanostructural vacancy behavior of bovine derived hydroxyapatite (BHA) doped with powder zirconmullite (ZM) contents of 5, 7.5, 10 and 12.5 wt.% were presented at sintering temperatures of 1000, 1100, 1200 and 1300 degrees C. ZM-doped BHA (ZM-BHA) was characterized by X-ray diffraction and positron annihilation lifetime spectroscopy (PALS). Density and hardness behavior were measured with respect to increasing sintering temperature. PALS results indicate that the longest lifetime component tau(3) of ortho-positronium (o-Ps) localized at open spaces is attributed to the vacancy site and almost constant with the ZM contents and the sintering temperatures to have a mean value of 0.680 ns (corresponding to the radius of 0.997 nm). This average value is ascribed to the OH group defects along the main crystalline line. On the other hand, the o-Ps intensity attributed to the number of vacancy sites increases almost linearly with ZM additives and sintering temperatures. The intensity is also related to the density and hardness of ZM-BHA in terms of ZM contents.

In this study, the effect of different laser beam power on the nanoindentation and corrosion properties of Ti-6Al-4V alloys fabricated direct metal laser sintering (DMLS) method was investigated. Ti-6Al-4V samples were fabricated by DMLS method with three 34.72 J/mm3, 64.81 J/mm3 and 83.33 J/mm3 energy densities named as sample 1, sample 2 and sample 3, respectively. The microstructure and crystalline phase of Ti-6Al-4V samples were analyzed by optical microscope, SEM and XRD devices. Microstructural examinations showed that microstructure of Ti-6Al-4V samples consisted of the prior columnar β grains and α/α´ phases. The β phase proportion soared with rising laser beam power. Nanoindentation results illustrated that the order of reduced elastic modulus (Er) values was sample 1 > sample 2 > sample 3. The order of hardness (H) values followed sample 1 > sample 2 > sample 3. The H/ Er ratios were found to be 0.0338, 0.0333, and 0.032 for samples 1, 2, and 3, respectively. The H3/Er2 ratios were estimated to be 0.00734 GPa, 0.00633 GPa, and 0.00513 GPa for samples 1, 2, and 3, respectively. The presence of high values means better anti-wear capacity and good resistance to deformation for samples based on nanoindentaion findings. Moreover, electrochemical measurements depicted that the value of corrosion current density (icor) of the samples ordered as sample 3 > sample 2 > sample 1. The sample 1 exhibited better corrosion resistance than other samples. The findings showed that as the laser power is low, DMLS Ti-6Al-4V samples potentially have better mechanical and corrosion performance due to low β content and high α´ phases in the microstructure.

Tapping is a typical machining method being utilized in manufacturing internal threads. However, it contains few difficulties to be dealt with since during the process, many cutting edges involve synchronized axial and rotational movements. This work presents the results of an experimental study on the material type considering the influences of the manufacturing process (extrusion and forging) and tap type on the surface integrity characteristics of lead-free brass alloys. Experimental data on the surface quality of the threads, subsurface characteristics including microhardness is presented and analyzed. This study demonstrates that the manufacturing methods have a robust effect on microstructural aspects of low-lead brass alloy and resulting in hardening of the surface and subsurface.

This paper presents a deployment method of various test maneuver scenarios for 2 degree of freedom (2 DoF) vehicle simulator by using feature extraction and neural networks (NN). A prototype version has been set up for the 2 DoF vehicle simulator. Then, a hardware in the loop (HIL) model with 2 inputs (torque, τ1-τ2) and 3 outputs (acceleration, ax-ay-az) is created. System identification is performed to obtain the training data of NNs to be used for the deployment of test maneuvers. In the system identification process, 2 arbitrary sinusoidal torque signals (τ1-τ2) are generated by using the actuator specs of the 2 DoF vehicle simulator. By applying the generated torque signals to the actuators, acceleration (ax-ay-az) data are collected from the inertial measurement sensor (IMU) on the 2 DoF vehicle simulator. It is determined to create 3 different NN models for the obtained data. The 1st NN model is trained with 3 inputs (ax-ay-az) and 2 targets (τ1-τ2) training data. The 2nd NN model is trained with 6 inputs (amplitudes and phases of ax-ay-az) and 2 targets (τ1-τ2) training data. The input data features for the 2nd NN model is extracted by using the Fast Fourier Transform (FFT). The 3rd NN model is trained with 6 inputs (amplitudes and phases of ax-ay-az) and 4 targets (amplitudes and phases of τ1-τ2) training data. For the 3rd NN model, the features of input and target data are extracted by using the FFT. The NN training process continues until acceptable performance criteria are reached. Then, 3 NN models are run and analyzed under various test scenarios such as Double Lane Change, Constant Radius, Increase Steer, Fish Hook, Sine with Dwell and Swept Sine. Only for the 3rd NN, the actuator signals (τ1-τ2) are recomposed by applying an inverse FFT process to the 4 targets (amplitudes and phases of τ1-τ2). Finally, the reference trajectory tracking performances are evaluated by comparing the NN models that are run under the test scenarios.

This study aims to obtain nanoparticles by electrospinning method using xanthan gum (XG) and gelatine (GEL) polymers. For the development of these nanoparticles, ten different groups were produced. In some groups, nanofiber was obtained instead of particles. The nanofiber formation was determined in the 10 wt% GEL, 12 wt% GEL, 3 wt% XG, 8 wt% GEL + 3 wt% XG. 12 wt% GEL + 0.1 wt% XG groups. 4 wt% GEL + 1 wt% XG and 8 wt% GEL + 3 wt% XG groups showed nanoparticles structure. To assess the nanofibers chemical properties, Fourier transform infrared spectroscopy (FTIR) were used. Scanning electron microscopy (SEM) was used to characterize mechanical and morphological properties. Physical properties and swelling behaviours were examined to analyse the samples. As a result of the swelling test, 3 wt% XG was degraded, 10 wt% and 12 wt% gelatin groups started to degrade after the fourth day. Our work deduced that GEL/XG nanoparticles could use for carrier purposes. Also, this study was beneficial in finding the right ratios in the production of nanoparticles and nanofibers from the XG/GEL mixture by electrospinning. In addition, proper electrospinning parameters in nanofiber and nanoparticles production are also important results of the study and will be further used in developing composite nanostructures with regenerative or drug release capability.

Identification of wood species with fast, reliable and non-destructive methods is highly important for forestry and wood-related industries. Near-infrared spectra of anatomically similar pine species (Pinus sylvestris L. and Pinus nigra J.F. Arnold) were taken and analysed by partial least squared discriminant analysis (PLS-DA) for comparing the efficiency of preprocessing methods. Raw data were subjected to multiple scatter correction (MSC), standard normal variate (SNV), Savitzky-Golay for derivatives (1st and 2nd Dr) and smoothing (Sm) and combination of these preprocessing methods (1st Dr, 1st Dr + SNV, 1st Dr + MSC, Sm + 1st Dr and Sm + 2nd Dr). The success of the models was determined by the accuracies of test sets that did not participate in the calibration phase. In this study, it was determined that not all the preprocessing methods improve the model performance. Smoothing with 1st derivatives (Sm + 1st Dr) enhanced 14.3% improvement and have the best performance (95%) for classification of pine species. For understanding modelled relationship, mean spectra and selectivity ratio were used. It was found that discrimination was held by the differences at their absorption, and the most important variables for wood classification were noted around 4000-7000 cm(-1).

The use of textiles in soft robotics is gaining popularity because of the advantages textiles offer over other materials in terms of weight, conformability, and ease of manufacture. The purpose of this research is to examine the stitching process used to construct fabric-based pneumatic bending actuators as well as the effect of segment types on the actuators’ properties when used in soft robotic glove applications. To impart bending motion to actuators, two techniques have been used: asymmetry between weave and weft knit fabric layers and mechanical anisotropy between these two textiles. The impacts of various segment types on the actuators’ grip force and bending angle were investigated further. According to experiments, segmenting the actuator with a sewing technique increases the bending angle. It was discovered that actuators with high anisotropy differences in their fabric combinations have high gripping forces. Textile-based capacitive strain sensors are also added to selected segmented actuator types, which possess desirable properties such as increased grip force, increased bending angle, and reduced radial expansion. The sensors were used to demonstrate the controllability of a soft robotic glove using a closed-loop system. Finally, we demonstrated that actuators integrated into a soft wearable glove are capable of grasping a variety of items and performing various grasp types.

High-intensity electrical discharges are used in the unconventional technique known as electrical discharge machining (EDM) to machine metals of any hardness. Due to their extraordinary conductivity and strength, carbon nanotubes (CNTs) have recently been explored in EDM too. However, material removal with CNT yarn (CNTY) has not been studied thoroughly. This work advocates the use of a pristine CNTY as an EDM tool. The feasibility is examined through characterization and material removal experiments. The measurements show that the CNTY ( 100 mu m) multi-ply tools extend tool life and, therefore, machining time by more than 14 s in the air and nearly 2.5 s in the oil. Other factors that restrict machining include intensified discharges and the shielding effect of the carbide layer formed on the workpiece.

© 2022 by the authors.This research aims to estimate the delivery time and energy cost of e-scooter vehicles for distributing mail or packages and to show the usage efficiency of e-scooter sharing services in postal service delivery in Turkey. The machine learning (ML) methods used to implement the prediction of delivery time and energy cost as output variables include random forest (RF), gradient boosting (GB), k-nearest neighbour (kNN), and neural network (NN) algorithms. Fifteen input variables under demographic, environmental, geographical, time, and meta-features are utilised in the ML algorithms. The correlation coefficient (R2) values of RF, GB, NN, and kNN algorithms were computed for delivery time as 0.816, 0.845, 0.821, and 0.786, respectively. The GB algorithm, which has a high R2 and the slightest margin of error, exhibited the best prediction performance for delivery time and energy cost. Regarding delivery time, the GB algorithm’s MSE, RMSE, and MAE values were calculated as 149.32, 12.22, and 6.08, respectively. The R2 values of RF, GB, NN, and kNN algorithms were computed for energy cost as 0.917, 0.953, 0.400, and 0.365, respectively. The MSE, RMSE, and MAE values of the GB algorithm were calculated as 0.001, 0.019, and 0.009, respectively. The average energy cost to complete a package or mail delivery process with e-scooter vehicles is calculated as 0.125 TL, and the required time is approximately computed as 11.21 min. The scientific innovation of the study shows that e-scooter delivery vehicles are better for the environment, cost, and energy than traditional delivery vehicles. At the same time, using e-scooters as the preferred way to deliver packages or mail has shown how well the delivery service works. Because of this, the results of this study will help in the development of ways to make the use of e-scooters in delivery service even more efficient.

This work aimed to comprehensively assess the influence of various surface modifications on the formation of apatite ability for EBM Ti-6Al-4V alloy. Sandblasting (S), acid-etching (E), sandblasting and acid-etching (SE), anodization (NA), micro-arc oxidations in 1M H2SO4solution (SM) and 1M H3PO4solution (PM) methods were applied to modify electron beam melted (EBM) Ti-6Al-4V surface. The α/α’-Ti structures and TiO2phases were detected by XRD. The surface roughness (Ra) values ranged from 0.25 μm and 2.86 μm. The wettability of samples was between around 25° and 104°. The SM sample possessed the lowest contact angle. In vitro tests were employed in the simulated body fluid (SBF) solution for 28 days. The samples with different surface textures demonstrated bioactive behaviors. In vitro test results showed that apatite layers formed on the surfaces. The SM sample exhibited good apatite formation ability when the Ca/P ratios were considered. The apatite formation for the SM sample might derive from high roughness, low contact angle value, the existence of Ti-OH groups, and anatase and rutile phases. The SM can be implemented to boost bioactivity on EBM Ti-6Al-4V alloys.

Bioceramics are a fast-growing materials group, which are widely used in orthopedics, maxillofacial, dental, and reconstructive surgeries. They are produced using raw materials either from synthetic or natural sources. As naturally originated resources, the bones of sheep and cows are used after converting to calcium phosphates. Human-originated sources in the past were obtained from human cadaver bones, however now-a-days this has been discontinued. On the other hand, the “golden standard” in the reconstruction surgery has been using patients own bones, -i.e., autogenous bones, which heal better than other alternatives. Besides natural products, synthetic materials are produced from a range of inorganic raw and natural materials based on marine sources, such as corals, and other marine-derived materials (i.e., seashells, nacre). These are used to produce bioceramics and hence implants, devices, and bone grafts. Although during the last four decades a number of excellent books and book chapters have been published, no comprehensive review has been yet reported to cover the available marine materials and to indicate the related work and corresponding references to allow for both medical and ceramic scientists to access directly and open new avenues for further research on marine structures and their applications in orthopedic, maxillofacial, and reconstructive surgery areas. Hence, this review covers the general marine structures, their locations and availability in different countries and, current research on production methods of these unique structures that are difficult to fabricate synthetically. The authors are confident that this comprehensive review will be an excellent source not only for the ceramists, but also for the medical scientists.

In this study, two novel silicon phthalocyanines (SiPc) having axial anchoring groups (3: SiPc carrying bis-dibutyl phenoxy acrylic acid and 5: SiPc carrying bis-dibutyl phenoxy carboxylic acid) are synthesized as the photosensitizers of dye sensitized solar cells (DSSCs). The obtained novel photosensitizers are elucidated by using 1H NMR, MALDI-TOF, FT-IR, UV-Vis spectroscopy, and elemental analysis. Moreover, the electrochemistry of SiPcs is investigated with voltametric and in-situ spectroelectrochemical analysis. Both SiPcs illustrate similar two reductions and one oxidation Pc based redox processes. In-situ spectroelectrochemical results support the Pc based characters of the voltametric responses. The chromaticity diagrams and optical responses of the anionic and cationic moieties are recorded with the in-situ spectroelectrochemistry to determine the viability of them for various photoelectrochemical usage. Finally, SiPcs are investigated as dyes in DSSCs in order to investigate the influence of bis-dibutyl phenoxy acrylic acid and bis-dibutyl phenoxy carboxylic acid anchoring groups to the photovoltaic performance of SiPcs. DSSCs sensitized with SiPc (3) and SiPc (5) illustrate good photovoltaic performance with 1.48 and 1.99 mA/cm2 short circuit current density, 0.751 and 0.657 V open circuit potential, 0.52 and 0.57 fill factor, and 0.57% and 0.75% power conversion efficiency respectively.

In this study, sodium caseinate/starch/ tri-calcium phosphate (TCP) base scaffolds were fabricated and cross -linked with microbial transglutaminase. A Maillard reaction was carried out to stabilize the blend of sodium caseinate (8% w/w) and starch (8% w/w) solutions. The dynamics of enzymatic cross-linking activity were assessed with different TCP concentrations. Freeze-dry method was used to extract water from the gel system to acquire a porous, spongy structure. Apart from many other enzymes, microbial transglutaminase has the capa-bility to be active even below freezing temperatures. Keeping at-50 degrees C for 12 h, enzymes were still active to complete the post-crosslinking process. 0.5% TCP case resulted in 690 kPa ultimate tensile strength at dried state. Cell activity and characterization tests were elucidated and observed that those scaffolds can have very prom-ising applications in bone tissue engineering.

© 2022 The Royal Society of Chemistry.Non-covalent functionalization of single wall carbon nanotubes (SWCNTs) has been conducted using several binding agents with surface π-interaction forces in recent studies. Herein, we present the first example of non-covalent functionalization of sidewalls of SWCNTs using thienothiophene (TT) derivatives without requiring any binding agents. Synthesized TT derivatives, TT-CN-TPA, TT-CN-TPA2 and TT-COOH-TPA, were attached directly to SWCNTs through non-covalent interactions to obtain new TT-based SWCNT hybrids, HYBRID 1-3. Taking advantage of the presence of sulfur atoms in the structure of TT, HYBRID 1, as a representative, was treated with Au nanoparticles for the adsorption of Au by sulfur atoms, which generated clear TEM images of the particles. The images indicated the attachment of TTs to the surface of SWCNTs. Thus, the presence of sulfur atoms in TT units made the binding of TTs to SWCNTs observable via TEM analysis through adsorption of Au nanoparticles by the sulfur atoms. Surface interactions between TTs and SWCNTs of the new hybrids were also clarified by classical molecular dynamic simulations, a quantum mechanical study, and SEM, TEM, AFM and contact angle (CA) analyses. The minimum distance between a TT and a SWCNT reached up to 3.5 Å, identified with strong peaks on a radial distribution function (RDF), while maximum interaction energies were raised to −316.89 kcal mol−1, which were determined using density functional theory (DFT).

Twin-roll casting (TRC) is a process in which liquid metal is introduced directly between counter-rotating water-cooled rolls, where it solidifies and is rolled to a strip having final thickness of 3 to 8 mm. TRC for aluminum is best suited to those alloys having a narrow freezing range with little susceptibility to hot tearing, such as 1XXX, 3XXX, 5XXX, and 8XXX. TRC offers advantages over conventional DC casting followed by hot and cold rolling for these alloys due to its lower capital cost, and decreased downstream processing operational cost and energy consumption, since hot rolling is not required. The microstructure formed in the strip must be carefully controlled, because as a near-net shape product used mostly for non-age-hardenable alloys, there is limited opportunity to modify it by subsequent processing. In particular, the near-surface microstructure has a strong effect on performance in forming applications. In this article, we present a computational model of TRC, and validate it for AA1050 aluminum alloy in a production environment. The novel aspect of this work is that the model is used to predict the final microstructure and crystallographic texture of the cast strip. The model is validated in plant trials for strip cast at a range of thicknesses, casting speeds, and caster setup by comparing the predicted microstructure, texture, and process outcomes such as roll separating force and forward slip to their corresponding measured values. We then apply the validated model to explore process parameters outside the standard practices, including feed inlet setback, casting speed, metal inlet temperature, and changing roll material to demonstrate how the microstructure and texture can be controlled via these parameters. (C) The Minerals, Metals & Materials Society and ASM International 2022

Layered double hydroxides (LDHs) offer unique source of inspiration for design of bone mimetic biomaterials due to their superior mechanical properties, drug delivery capability and regulation cellular behaviors, particularly by divalent metal cations in their structure. Three-dimensional (3D) bioprinting of LDHs holds great promise as a novel strategy thanks to highly tunable physiochemical properties and shear-thinning ability of LDHs, which allow shape fidelity after deposition. Herein, we introduce a straightforward strategy for extrusion bioprinting of cell laden nanocomposite hydrogel bioink of gelatin methacryloyl (GelMA) biopolymer and LDHs nanoparticles. First, we synthesized LDHs by co-precipitation process and systematically examined the effect of LDHs addition on printing parameters such as printing pressure, extrusion rate, printing speed, and finally bioink printability in creating grid-like constructs. The developed hydrogel bioinks provided precise control over extrudability, extrusion uniformity, and structural integrity after deposition. Based on the printability and rheological analysis, the printability could be altered by controlling the concentration of LDHs, and printability was found to be ideal with the addition of 3 wt % LDHs. The addition of LDHs resulted in remarkably enhanced compressive strength from 652 kPa (G-LDH0) to 1168 kPa (G-LDH3). It was shown that the printed nanocomposite hydrogel scaffolds were able to support encapsulated osteoblast survival, spreading, and proliferation in the absence of any osteoinductive factors taking advantage of LDHs. In addition, cells encapsulated in G-LDH3 had a larger cell spreading area and higher cell aspect ratio than those encapsulated in G-LDH0. Altogether, the results demonstrated that the developed GelMA/LDHs nanocomposite hydrogel bioink revealed a high potential for extrusion bioprinting with high structural fidelity to fabricate implantable 3D hydrogel constructs for repair of bone defects. WOS:000865405500001 Q2

© 2022 American Society of Civil Engineers.Topology optimization studies have found widespread use with advances in additive manufacturing technologies. A topology optimization method is proposed for the design of a fatigue critical part, namely, a pitch arm made of Al 7050, which transmits the commands to change the pitch attitude to the rotor blades of the helicopter. This study used the bidirectional evolutionary structural optimization (BESO) method with the fatigue failure criterion of a closed Soderberg (CS). The mean stress and stress amplitude values used in the procedure were obtained by applying the Manson-McKnight method. The calculations were performed using a Python-based script compatible with Ansys version 2021 R1 software. In the finite-element calculations, the sensitivity number of the elements was determined using the results of the linear static analysis. A volume constraint was applied in the formulation of the optimization problem to minimize the weight of the structure. The results of the classical topology optimization approach and the developed optimization method were compared. The final geometries of both approaches showed that the ranges of volume reduction differed from each other. It was found that the values for the new fatigue-optimized weight of the pitch arm were 18% higher than the values for the static-based classical topology optimization method. However, in general, the weight of the part obtained as a result of fatigue-based topology optimization was reduced by 34% in total.

The marine species are specially used for the fabrication of bioceramic nano-powders with natural methods for their use in controlled drug delivery. However, there are only very limited studies regarding the production and synthesis of hydroxyapatite (HA)-based drug delivery systems from marine structures. In this study, poly (vinyl alcohol) (PVA) containing Rifampicin (RIF)-loaded Orange Spiny Oyster Seashell (Spondylus barbatus) hydroxyapatite (HA) composite is synthesized by an in situ ultrasound-assisted method. All samples were analyzed by X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy, and Scanning electron microscope (SEM), respectively. The in vitro drug release tests of the obtained samples were performed in a phosphate-buffered medium (PBS) at 37 degrees C. Drug release was evaluated according to five varying kinetic models. In vitro RIF release from HA/PVA composite in phosphate buffer (pH 7.4) showed prolonged sustained drug release. From the drug release kinetic models, Higuchi and Korsmeyer-Peppas were found to be the best model for the three ratios based on the correlation coefficient. The diffusion component is less than 0.5, which indicates quasi-fickian diffusion. From the kinetic study results, the RIF-loaded marine phase composite has potential use in drug delivery applications as it shows positive sustained drug release behavior.

Herein, a novel hyaluronic acid (HA)-based electroconductive hydrogel with enhanced mechanical properties was developed for the non-enzymatic glucose detection. As the main component of the polymeric network, HA was modified through methacrylation to integrate photocrosslinkable groups into its backbone. Electrical conductivity was provided to hydrogel by using two different conductivity sources as the introduction of reduced graphene oxide (rGO) and polyaniline (PANI) to HA-based hydrogel structure. The combination of these conductivity sources not only provided the sufficient electrical conductivity (1.58 ×10−5 S/cm) to hydrogels, but also ensured superior mechanical performance in terms of compressive strength (992.1 kPa) and elastic modulus (23.4 kPa) due to the synergistic effect of the rGO and PANI, that are the significant parameters for sensor applications. The electrochemical activity and sensor performance of the HA-based hydrogel were investigated via cyclic voltammetry (CV) and choronoamperometry (CA) methods. The fabricated HA-based hydrogel sensor exhibited high sensitivity as 421.42 µAmM−1cm−2 and selectivity for glucose with a low detection limit (0.3 µM). Moreover, it showed excellent long-term stability, reproducibility and anti-interference feature towards uric acid, ascorbic acid and sorbitol. Based on these results it could be stated that the developed HA-based hydrogel sensor containing ternary HA-rGO-PANI formulation for the first time in the literature might be served as a promising potential for the non-enzymatic glucose detection and it also offers a new perspective for fabricating efficient hydrogel-based biosensing systems for future studies.

The continuous and prolonged releases of chemotherapeutic drugs are required for successful treatment in cancer treatment. The project focused on a new material design to meet this requirement. We developed a constant and sustained release system and investigated the release profiles of Paclitaxel (PTX). Polylactic acid (PLA) nanofiber surface was grafted with poly (methacryloyloxyethyl phosphorylcholine) (PMPC) by the UV-induced grafting method. The morphological structure of the PLA nanofibers did not change with an increase in the MPC content. PMPC blocks contribute to the solubility of PTX, which shows low resolution. When the amount of MPC is 5%, the PTX loading efficiency increased two times compared with PLA nanofiber. The nanofiber mats exhibited an initial fast release during the first 3 h. Endothelial cells were cultured on nanofiber mats to investigate whether this material was toxic or not. The mats showed good biocompatibility with HUVEC. Thus, it was confirmed that nanofiber mats would not be toxic when releasing drugs during in vivo use. We think that PMPC facilitates the pass of drugs through the lipid-rich biological membrane and so anticancer drugs can be delivered to direct tumor sites. (C) 2022 Elsevier Ltd. All rights reserved.

The use of metal-free click reactions for the design and synthesis of novel flame retardant reactive monomers for thiol-ene photopolymerization is an intriguing area of research. In this study, we have prepared a new, 9,10-dihy-dro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based, P-and N-containing reactive flame retardant via the metal-free azide-alkyne click reaction. For this purpose, first, azide-functionalized DOPO (DOPO-N-3) has been synthesized via Atherton-Todd reaction, and then this compound has been reacted with acetylene dicar-boxylic acid diallyl ester (ACDAE) to give the flame retardant monomer, namely DOPO-triazole diallyl ester (DTDAE). As prepared flame retardant monomer was characterized by nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR) spectroscopies. Thermoset materials prepared by using DTDAE displayed over 90% gel content values. Polar triazole and phosphorous units rendered the surface of the ther-mosets hydrophilic. The thermal stability of the networks was enhanced, char yields increased and the glass transition temperatures (T(g)s) were increased. The limiting oxygen index (LOI) values of the crosslinked materials increased up to 27.8% as the DTDAE content was increased in the formulations. The synthetic method described in this study provides a practical approach for the synthesis of a P-and N-containing flame retardant through a metal-free azide-alkyne click reaction Also, the fact that DTDAE is in a liquid state makes this study valuable as it indicates that it can be easily dispersed. It is also believed this promising compound can be used in different polymer structures and formulations to develop new flame retardants in future studies to be applied in industrial applications.

Mimicking the innovative structure, design and multifunctional mechanisms of biological process based sustainable biosensor technology in living creatures is highly successful with multilingual features that draw in constantly more and more research efforts and extensive attention from the numerous species of diagnosis and clinical origins. This review will provide a comprehensive overview with respect to the innovative approach for identify, recognizing and showcasing the current advancements and key milestones accomplished in this field, aiming to provide an exclusive outlook for the bioderived materials and their most relevant applications to encourage readers to explore the uncharted realms of sustainable biointerfaces in the last 5 years.

In this study, 10 mg fluconazole (10 FCZ) and 10 mg gentamicin (10 GEN) loaded with 40% polymethylmethacrylate (40% PMMA) fibers were fabricated by electrospinning and the performance of the formulations (40% PMMA, 40% PMMA/10 FCZ, 40% PMMA/10 GEN, and 40% PMMA/10 FCZ/10 GEN) was tested. 10 mg Gentamicin-loaded 40% PMMA fiber mat showed a more significant zone of inhibition against the S. aureus compared to the zone of 40% PMMA/10 GEN/10 FCZ fiber. The biocompatibility test using a human adipose-derived mesenchymal stem cell (MSCs) as a cell model proved that the amount of loaded and released GEN has no toxic effects on the MSCs.

Tedious trial-and-error procedures are commonly practiced for surface modification of the perovskite solar cell (PSC) active layers. A guideline to rationally choose the passivating functional groups of the polymeric structure that is eminently effective in passivating the charged defects and elongating the device lifetime is hence in urgent demand. Herein, three prototypical polymers, poly(vinyl acetate) (PVA), polyethylene glycol (PEG), and poly(9-vinylcarbazole) (PVK), are selected to investigate the structural effect of the polymeric modification agents on the PSCs. We found that PVA possesses the Lewis base functional group with the minimized steric hindrance and the strongest electron-donating ability, enabling the most effective defect passivation on the perovskite film surface and the most enhanced carrier diffusion capacity. It demonstrates a power conversion efficiency (PCE) of 23.20% and noticeably enhanced operational stability. Our work provides important insights toward the selection of polymeric modification agents for high-performance and long-term stable PSCs.

In the present study, poly(lactic acid) (PLA) and poly(ethylene succinate) (PESu) or poly(ethylene glycol) (PEG) under the framework of quality by design, were blended to produce effective sustained-release matrices for Paclitaxel delivery. A complete physicochemical characterization including weight variation, thickness, water uptake, moisture absorption, moisture loss, and hydrolytic degradation under physiological conditions, was performed. Quality by design approach was applied to study the critical parameters. In vitro cancer toxicity was studied in human cancer cell lines including lung and breast adenocarcinoma. The developed Paclitaxel-loaded films can act as a promising alternative topical matrix as an implant for breast and lung cancer treatment. © 2022 Taylor & Francis Group, LLC. 2-s2.0-85130053009

The ongoing age is the time of sustainability, where in the current pandemic scenario, which is getting worse, needs treatment with nature rather than chemical-based products. In this study, microwaves (M.W. rays) treatments as extraction mode for Esfand (P. harmala) have been revived for polyamide (nylon) dyeing. The water solubilized and acid solubilized filtrates and polyamide (nylon fabrics) were treated M.W. rays up to 10 min with an interval of 2 min. Mordanting with chemicals and plant extracts before and after dyeing was done at 60 degrees C-80 degrees C. It has been found the application of M.W. ray treatment for 4 min., to 30 mL of extract of 8 pH containing 4 g/100 mL of Table salt as leveling agent has given desired results when employed at 55 degrees C for 55 min. Statistical analysis of dyeing variables through R.S.M., and two way-Anova shows that the effect of these variables has been observed highly significant. Experimentally it has been observed that the application of extract for dyeing of polyamide (nylon fabric) has given good results when chemical or bio-mordanted at selected conditions. Practically, Esfand seeds has ability for bio-coloration of surface modified polyamide fabric (nylon fabric), and utilization of pomegranate extract as bio-mordant and tannic acid as sustainable chemical mordant has furnished colorfast shades.

The further development of composite manufacturing methods is characterized by the progress of their mechanical properties which are widely used in many applications as automotive, aerospace, and marine industries. The automated composite production techniques are as follows: automatic tape layering, automatic fiber placement, and filament winding methods used in many industries. Photopolymerized composites and their additive manufacturing methods are promising with new advances in technology. This method for printing continuous fiber-reinforced plastic composite parts by a six-axis industrial robotic arm is based on fused deposition modeling technology. The objective of this work is to obtain a better understanding of the mechanical properties of robotic three-dimensional printed photopolymer resin continuous fiberglass–reinforced composites (CFGRCs) as a function of different printing speeds (10, 20 and 30 mm/s), fiber densities (45, 55 and 65%), and fiber orientations (0, 0/90 and ±45°). This work infers that mechanical properties are significantly affected by the fiber density and fiber orientation of CFGRC. With this method, approximately 300 MPa tensile strength can be obtained and structurally preferred instead of ferrous materials in many areas.

This study aims to design an alternative way for the laminated fabric manufacturing with a cleaner production method, by using a bio-based coating formulation and time/cost saving, environmentally friendly UV-curing technology, compared to the conventional petroleum based, heat and solvent requiring laminating process. For this purpose, acrylated epoxidized soybean oil oligomer was synthesized and included in coating formulations for the application on cotton fabrics via UV-curing. The obtained oligomer was characterized by FTIR and NMR spectroscopies. In order to enhance the bonding between the fabric and coating layer, fabrics were pretreated by sodium hydroxide, pectinase enzyme, and a commercial washing agent prior to the coating process. The effects of pretreatment methods on the wettability, tensile and peel strength, and abrasion resistance of the fabrics were all examined before/after coating process. Enzyme pretreatment revealed promising results by increasing the surface roughness, fibrillation, and hydrophilicity of the cotton fabrics. After coating and UV-curing process, the highest increment in tensile strength, the highest peel strength, and the least weight loss value against abrasion were all recorded in enzyme pretreated fabric.

Electrospun patches have attracted interest in different biomedical fields, including tissue engineering and drug delivery. Portable electrospinning guns promise faster and more practical interventions in these areas. In this article, the design, construction and testing of a portable electrospinning gun are described to produce fiber and particle products. Results were discussed depending on the electrospinning gun\"s working system and properties of the products. The electrospinning gun system could have a high voltage of up to 30 kV. Also, no heating problems were encountered during high voltage values. Due to the uniformity, reproducibility and tunability of the produced PCL and PMSQ fibers, it can be said that electrospinning gun can be used in nanotechnology, drug delivery systems and wound dressing applications.

Peripherally tetra-4-carboxyethylphenoxy substituted oxotitanium (IV), cobalt(II), zinc(II) and metal free phthalocyanines were synthesized to research the sensitizing abilities of these dye molecules in standard dye sensitized solar cells (DSSCs). All the synthesized phthalocyanine complexes have been characterized by using elemental analyses, UV-Vis, FT-IR, H-1 NMR and MALDI-TOF MS spectroscopic techniques. Electrochemistry of metallo phthalocyanines (MPcs) were studied with electrochemical and in-situ spectroelectrochemical measurements. H2Pc (7) and ZnPc (5) illustrated similar Pc based electron transfer reactions. Differently, CoPc (6) and TiOPc (4) illustrated metal based redox reactions, which enhanced the redox functionality of these complexes. Metal based reductions for CoPc (6) and TiOPc (4) were recorded in addition to the Pc based one. In-situ spectroelectrochemical measurements supported the proposed voltametric mechanism. Moreover, the color and spectra of the electrogenerated species were determined with the in-situ spectroelectrochemical analyses to predict possible optoelectrochemical application of the complexes. Pronounced optical and color changes during the electrolysis of the complexes indicated electrooptical and possible solid state electrochemical functionality of the complexes. TiO2 semiconductor on the fluoride doped indium tin oxide coated glass electrode (FTO) was decorated with H2Pc (7) and TiOPc (4) bearing four carboxyl anchoring groups and they were first of all tested as possible dye for the DSSC. H2Pc (7), TiOPc (4), CoPc (6) and ZnPc (5) dyes used in DSSCs showed 2.9%, 3.3%, 1.02% and 2.2% of power conversion efficiencies respectively.

In this study, a new Donor-Acceptor-Donor (D-A-D) electroactive molecules (HCQM1 and HCQM2) containing 9H-carbazole and 9-phenyl-9H-carbazole as donor along with quinoxaline (HQ) as acceptor were synthesized and then coated on Indium Tin Oxide/Glass (ITO/Glass) surface by the electrochemical oxidation process. The HOMO-LUMO band gap values obtained by electrochemical oxidation and reduction onsets were calculated as 2.64 and 2.68 eV, respectively. On the other hand, UV-Vis absorption measurements showed that the charge transfer band of HCQM1 was detected at 500 nm with 50 nm red shift upon compared with the HCQM2. According to AFM results, it is seen that the roughness of the poly(HCQM2) film is higher than the poly(HCQM1) film. Finally, the polymer film of HCQM2 showed multi-electrochromic color change (yellow, green, and dark blue) upon the oxidation process. When the electrochromic performance of the HCQM1 and HCQM2 polymer films was compared, it was discovered that the HCQM2 with phenylene spacer unit has better stability and a higher percentage transmittance change (& UDelta;T%) between neutral and oxidized states.

This paper proposes a framework to extract knowledge-management elements from business systems in healthcare organizations. According to results of in-depth interviews with experts in the field, a framework is defined, and software was developed to generate log files. Following the application of the Bag of Words (BoW) method on log files of 455 days for feature extraction, the k-means algorithm was used to cluster the feature vectors. The framework was tested with queries for confirmation. The developed framework successfully clustered the generated reports at operational, tactical, and strategic levels to extract knowledge-management elements. This study provides evidence for the knowledge-management pyramid by finding that the generated reports are reviewed mostly at the operational level, then tactical, and then the least at the strategic level. Our framework has the potential to be used not only in the health sector, but also in banking, insurance, and other businesses using business intelligence, especially in accordance with the organization’s goals at operational, tactical, and strategic levels of the knowledge-management pyramid.

In this study, metal and metal-free novel phthalocyanines containing peripheral and non-peripheral tetra 2-ben-zylphenoxy groups were synthesized. The compounds were characterized by UV-Vis, FT-IR, H-1 NMR, and MALDI-TOF mass spectrometry as well as elemental analysis. These new phthalocyanines exhibited excellent solubility in most organic solvents, and their redox behavior was investigated in different solvents such as dimethyl sulfoxide (DMSO) and dichloromethane (DCM). The redox behavior of the peripheral and non-peripheral phthalocyanine compounds 1a -c and 2a -c was determined by cyclic voltammetry and in situ spec-troelectrochemistry. According to organic field-effect transistors (OFETs) measurements, the peripheral and non-peripheral phthalocyanine-cobalt complexes which have higher mobility than others were utilized top-gate bottom-contact OFETs fabrication. The output characteristics of the device show that its mobility is approximately 5 x 10(-2) cm(2)/Vs with p-type accumulation.