Functionally Graded Materials Optimization Using Particle Swarm-Based Algorithms

This article presents an application of particle swarm-based algorithms for volume fraction optimization of functionally graded materials. A simple and efficient method for constraint handling is included too. To optimize the material composition, two numerical examples are done. In the first example, the peak residual stresses are minimized when the FGM is cooled from a reference temperature. In the second example, the factor of safety against yielding are maximized for a temperature-dependent FGM sphere subjected to thermal gradients. The algorithms PSO, PSOPC, PSACO and PSPCACO are used too and the optimum volume fraction are obtained. According comparison of the results, particle swarm-based algorithms can be used as a powerful tool for optimizing the FG materials.     

Carbon Nanotube–Ionic Liquid (CNT–IL) Nanocamposite Modified Sol-Gel Derived Carbon-Ceramic Electrode for Simultaneous Determination of Sunset Yellow and Tartrazine in Food Samples

Carbon-ceramic electrode modified with multi-walled carbon nanotubes–ionic liquid (MWCNTs–IL) nanocomposite was constructed. This electrode was used for electrochemical determination of food dyes Sunset Yellow (SY) and tartrazine (Tz). The modified electrode based on high surface area and high ionic conductivity of nanocomposite exhibited electrocatalytic effect for oxidation of SY and Tz; also, oxidation peak potentials of SY and Tz effectively separated on modified electrode, and their simultaneous determination was possible. Operational parameters, such as the amount of MWCNTs in suspension, IL volume, solution pH, and scan rate, which affect the analytical performance of determination, were optimized. The present electrode behaved linearly to Sunset Yellow and tartrazine in the concentration range of 4?×?10^?7 to 1.1?×?10^?4?M and 3?×?10^?6 to 0.7?×?10^?4?M with a detection limit of 10^?7?M (0.045 mg?L^?1) and 1.1?×?10^?6?M (0.59 mg?L^?1), respectively. The proposed method was successfully utilized for simultaneous determination of SY and Tz in different food samples, and the obtained results were in good agreement to those obtained by HPLC method.     

Studies of the entrapment of non-wetting fluid within nanoporous media using a synergistic combination of MRI and micro-computed X-ray tomography

Three-dimensional magnetic resonance imaging (MRI) and micro-computed X-ray tomography (micro-CXT) have been combined to study the entrapment of mercury within nanoporous silica materials following porosimetry. MR images have been used to construct structural models of particular porous media within which several simulations of mercury intrusion and retraction have been performed with variations in the mechanism for the ‘snap-off’ of the mercury menisci. The simulations gave rise to different predictions for the pattern of the macroscopic spatial distribution of entrapped mercury, depending on ‘snap-off’ mechanism, which were then compared with corresponding experimental data obtained from micro-CXT images of real pellets containing entrapped mercury. The information obtained from the micro-CXT images, and also from the porosimetry curves themselves, was then used to constrain a model for the microscopic mercury retraction mechanism. Additional predictions of the retraction model were then subsequently confirmed using scanning loop experiments. The simulations showed that the overall level of entrapment of mercury was determined by the close interaction between the pellet macroscopic structure (particularly pore size spatial correlation), and the microscopic mercury retraction mechanism. Hence, it was subsequently possible to explain fully why high mercury entrapment occurred within one particular type of sol-gel silica material, while only low entrapment occurred in another batch of superficially similar material.     

Acute hemodynamic effects of metoprolol +/- nitroglycerin in patients with biopsy-proven lymphocytic myocarditis

This clinical case report demonstrates the clinical effectiveness of a new form of soft tissue mobilization in the treatment of excessive connective tissue fibrosis (scar tissue) around an athlete's injured ankle. The scar tissue was causing the athlete to have pain with activity, pain on palpation of the ankle, decreased range of motion, and loss of function. Surgery and several months of conventional physical therapy failed to alleviate the athlete's symptoms. As a final resort, augmented soft tissue mobilization (ASTM) was administered. ASTM is an alternative nonsurgical treatment modality that is being researched at Performance Dynamics (Muncip, IN). ASTM is a process that uses ergonomically designed instruments that assist therapists in the rapid localization and effective treatment of areas exhibiting excessive soft tissue fibrosis. This is followed by a stretching and strengthening program. Upon the completion of 6 wk of ASTM therapy, the athlete had no pain and had regained full range of motion and function. This case report is an example of how a noninvasive augmented form of soft tissue mobilization (ASTM) demonstrated impressive clinical results in treating a condition caused by connective tissue fibrosis.     

Dermatological indicators of coronary risk: a case-control study

Varicella pneumonia is the most common complication of adult varicella. Symptoms may be severe and the mortality rate high in patients who are immunodeficient or pregnant. Symptoms may be mild and progression more favorable in adults previously in good health. We report two cases of varicella infection complicated by severe pulmonary involvement in adult patients who were previously healthy. Case 1 was a 36-year-old male who 6 days after developing varicella was clinically observed to have dyspnea and hemopytsis. He died of acute respiratory failure on the following day. Case 2 was a 28-year-old male whose respiratory symptoms started the third day after developing varicella. These symptoms were relieved by treatment with acyclovir and gammaglobulin. Careful observation is and an early treatment of varicella should be undertaken not only for patients with suppressed cellular immunity, but also for healthy adults, to prevent severe complications.     

Bio‐nanocomposite films based on cellulose nanocrystals filled polyvinyl alcohol/chitosan polymer blend

Bio‐nanocomposite films based on polyvinyl alcohol/chitosan (PVA/CS) polymeric blend and cellulose nanocrystals (CNC) were prepared by casting a homogenous and stable aqueous mixture of the three components. CNC used as nanoreinforcing agents were extracted at the nanometric scale from sugarcane bagasse via sulfuric acid hydrolysis; then they were characterized and successfully dispersed into a PVA/CS (50/50, w/w) blend to produce PVA/CS–CNC bio‐nanocomposite films at different CNC contents (0.5, 2.5, 5 wt %). Viscosity measurement of the film‐forming solutions and structural and morphological characterizations of the solid films showed that the CNC are well dispersed into PVA/CS blend forming strong interfacial interactions that provide an enhanced load transfer between polymer chains and CNC, thus improving their properties. The obtained bio‐nanocomposite films are mechanically strong and exhibit improved thermal properties. The addition of 5 wt % CNC within a PVA/CS blend increased the Young's modulus by 105%, the tensile strength by 77%, and the toughness by 68%. Herein, the utilization of Moroccan sugarcane bagasse as raw material to produce high quality CNC has been explored. Additionally, the ability of the as‐isolated CNC to reinforce polymer blends was studied, resulting in the production of the aforementioned bio‐nanocomposite films with improved properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42004.     

Developing a new method for spatial assessment of drought vulnerability (case study: Zayandeh‐Rood river basin in Iran)

The paper presents an approach to spatially representative depiction for assessing the vulnerability of central Iran's Zayandeh‐Rood river basin to drought using multiple indicators. Drought conditions prevailed in the study basin from 2002 to 2007, with an annual rainfall deficiency of 45 to 55%. Multi‐attribute decision making (MADM) methods develop a framework to evaluate the relative priorities of drought assessment based on a set of preferences, criteria and indicators. The proposed MADM process uses well‐known techniques for product weights analytic hierarchy process (AHP) and order preference (TOPSIS). These indicators include the Standard Precipitation Index (SPI), water demand, the Palmer Drought Severity Index (PDSI) and the Groundwater Balance and Surface Water Supply Index (SWSI). Indicators' spatial information was categorised in layers prepared in the spatial domain using a geographic information system (GIS). The alternatives were ranked and presented using TOPSIS. Results show that the proposed method was highly effective in representing assessments of drought vulnerability.     

Equivalence of n-dimensional Roesser and Fornasini-Marchesinimodels

An equivalent Roesser model is obtained for an arbitrary Fornasini-Marchesini model in n-dimensions and vice-versa. Both the regular and singular cases are covered     

Interlaminar stresses in antisymmetric angle-ply cylindrical shell panels

Layerwise theory of Reddy is utilized for investigating free-edge effects in antisymmetric angle-ply laminated shell panels under uniform axial extension. Following some physical arguments, governing displacement field is divided into local and global parts. The former is discretized through the shell thickness by a zig-zag interpolation function while the latter is calculated by a first-order shear deformation theory. Local equilibrium equations are then solved through a state space approach. Accuracy of the proposed technical solution is subsequently verified by a novel analytical elasticity solution. For this end, the problem is analytically solved for specific boundary conditions along the edges. The numerical results show excellent agreement between two theories for various composite shell panels.