The effect of recycling number on the mechanical,chemical, thermal,and rheological properties of PBT/PC/ABS ternary blends: With and without glass‐fiber

The recycling possibilities of poly(butylene terephthalate)/polycarbonate/acrylonitrile–butadiene–styrene (PBT/PC/ABS) ternary blend with and without glass‐fiber content were investigated using repeated injection molding process. In this study, PBT/PC/ABS ternary blends were reprocessed at five times and the results were presented after each recycling process. The recycling possibility of PBT/PC/ABS ternary blend was evaluated by measuring the mechanical, chemical, thermal, and rheological properties. Mechanical properties were determined by the tensile strength, yield strength, strain at break, elastic modulus, impact strength, flexural strength, and flexural modulus. Chemical and thermal properties were evaluated by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal gravimetric analysis, and scanning electron microscopy. Rheological properties of the ternary blends were studied by melt flow index measurement. From the results, it was found that mechanical properties of recycled composites were better than virgin PBT/PC/ABS ternary blends. POLYM. COMPOS., 35:2074–2084, 2014. © 2014 Society of Plastics Engineers     

Challenges in Developing a Bessel-Beam Based Ultrafast Ablation Probe

Instruments and Experimental Techniques - With its elongated depth of focus, Bessel beams offer rapid and high aspect ratio ablation capability, in contrast to Gaussian beam counterparts. In this...     

Cellulose templating method for the preparation of La0.8Sr0.2Ga0.83Mg0.17O2.815 (LSGM) solid oxide electrolyte

La_0.8Sr_0.2Ga_0.83Mg_0.17O_2.815 (LSGM) materials are synthesized with a fast and facile cellulose templating method for the first time and characterized by XRD, EIS, Archimedes method and SEM–EDS. LSGM powders with a phase purity of 91.7 mol% are obtained after the calcination at 1300 °C for 12 h. SEM–EDS results indicate possible decomposition and reconstruction of the LSGM phase due to the diffusion of Sr-rich species to the grain boundaries for the sample sintered at 1500 °C for 6 h. Maximum conductivity value is found to be 4.2 × 10^?2 S cm^?1 at 800 °C for the sample calcined at 1300 °C for 12 h and sintered at 1400 °C for 6 h. Phase purity, stability and relative density are the important factors for obtaining high performance LSGM electrolytes. Therefore, cellulose templating method is a promising candidate for the preparation of LSGM electrolytes.     

Preparation and Characterization of PVA/PVP Nanofibers as Promising Materials for Wound Dressing

The PVA/PVP, PVA/PVP with 5% and 10% chitosan and PVA/PVP-Iodine fibers were produced via electrospinning technique. Their morphological and chemical characteristics were examined with SEM, TGA, FT-IR, viscometer and four-point probe conductivity measurement apparatus. The addition of chitosan increased the viscosity and the electrical conductivity of the polymer. The increase chitosan contents resulted in the diameters of the fibers smaller than expected. This was attributed to the increase in the viscosity of the solution and the electrical conductivity of the resulting fibers. The DSC results show that iodine was efficiently cross-linked with the polymer, forming an amorphous structure.     

Limited-Damage A*: A path search algorithm that considers damage as a feasibility criterion

Pathfinding algorithms used in todays computer games consider the path length or a similar criterion as the only measure of optimality. However, these games usually involve opposing parties, whose agents can inflict damage on those of the others. Therefore, the shortest path in such games may not always be the safest one. Consequently, a new suboptimal offline path search algorithm based on the A¹ algorithm was developed, which takes the threat zones in the game map into consideration. Given an upper limit as the tolerable amount of damage for an agent, this algorithm searches for the shortest path from a starting location to a destination, where the agent may suffer damage less than or equal to the specified limit. Due to its behavior, the algorithm is called Limited-Damage A¹ (LDA¹). Performance of LDA¹ was tested in randomly-generated maze-like grid-based environments of varying sizes, and in hand-crafted fully-observable environments, in which 8-way movement is utilized. Results obtained from LDA¹ are compared with those obtained from Multiobjective A¹ (MOA¹), which is a complete and optimal algorithm that yields exact (best) solutions for every case. LDA¹ was found to perform much faster than MOA¹, yielding acceptable sub-optimality in path length.     

Studies on an inhibitor produced by lactic acid bacteria of wines on the control of malolactic fermentation

Malolactic fermentation is the microbiological process in wines, where lactic acid bacteria (LAB) govern the process of converting L-malic acid into L-lactic acid. During this process a high microbial load of LAB may lead to an unwanted spoilage phenomena by formation of excessive amounts of undesirable flavor compounds. This study is mainly focused on the isolation of LAB from the native flora of the wine, which has an inhibitory potential against malolactic activity of LAB inherent in wines. An isolate of Leuconostoc mesenteroides subsp. cremoris was found to produce an inhibitory compound against the LAB of wines. This compound was found to be a bacteriocin-like inhibitory substance (BLIS), which has a molecular weight of 32,000 Da, and it was shown that this BLIS was effective in the control of malolactic fermentation.     

An extended Krylov subspace method to simulate single-phase fluid flow phenomena in axisymmetric and anisotropic porous media

We develop and validate a novel numerical algorithm for the simulation of axisymmetric single-phase fluid flow phenomena in porous and permeable media. In this new algorithm, the two-dimensional parabolic partial differential equation for fluid flow is transformed into an explicit finite-difference operator problem. The latter is solved by making use of an extended Krylov subspace method (EKSM) constructed with both positive and inverse powers of the finite-difference operator. A significant advantage of the method of solution presented in this paper is that simulations of pressure can be obtained at a multitude of times with practically the same efficiency as that of a single-time simulation. Moreover, the usage of inverse powers of the finite-difference operator provides a substantial increase in efficiency with respect to that of standard Krylov subspace methods. Tests of numerical performance with respect to analytical solutions for point and line sources validate the accuracy of the developed method of solution. We also validate the algorithm by making comparisons between analytical and numerical solutions in the Laplace transform domain. Additional tests of accuracy and efficiency are performed against a commercial simulator for spatially complex and anisotropic models of permeable media.     

Electrochemical corrosion properties of metal alloys used in orthopaedic implants

This study concerns an investigation of the corrosion behavior of 316 stainless steel, CoCrMo and Ti6Al4V alloys in simulated body conditions (ringer lactate) at 37 °C by the use of Tafel plots, mixed potential and electrochemical impedance spectroscopy (EIS). Ti6Al4V alloy has the highest corrosion resistance followed by CoCr alloy. Ti6Al4V–CoCrMO was the best couple for galvanic corrosion with the minimum galvanic potential and current values according to mixed potential theory and Tafel method. It was concluded that Ti6Al4V was the most suitable material for implant applications in the human body.     

Determination of cadmium and selected micronutrients in commonly used and traded medicinal plants in Turkey

BACKGROUND: Medicinal plants commonly used and traded in Turkey were monitored for their cadmium and selected micronutrient (copper, iron, manganese and zinc) content. RESULTS: Cadmium was not detected in any sample of licorice extract, linden flowers or nettle leaves. However, in the rest of the samples, cadmium was found in the range of 7–126 µg kg^?1, with the highest concentration in chamomile leaf. Of all the monitored trace elements, the highest concentration found was 520 mg kg^?1 iron in zahter. The highest copper, manganese and zinc concentrations were found in rose hips (24 mg kg^?1), Turkish oregano (58 mg kg^?1) and zahter (50 mg kg^?1), respectively. CONCLUSION: The results of the present study reveal that cadmium and trace element concentrations in medicinal plants commonly used as traditional medicines in Turkey are well below the critical levels. Copyright © 2007 Society of Chemical Industry