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In this article, a novel bi-objective integer model is presented to integrate reliability and intra-cell layout in designing a cellular manufacturing system (CMS). Minimising the total costs (e.g. inter and intra-cell material handling, machine overhead and operation, and setting up routes) is the first objective with considering operation time, operation sequence, intra-cell layout, alternative process routing, routes selection, machines capacity, parts demand and parts movements in batches. Maximising the processing routes reliability is the second objective. The presented model is capable of modelling different failure characteristics including a decreasing, increasing, or constant value for machine failure rate. An illustrative example is solved to represent the capability of the presented model using theε-constraint method in order to demonstrate the conflict between the maximum value of the system reliability and the total costs of the system. Next, a multi-objective imperialist competitive algorithm (MOICA) is employed to find near-optimal solutions for medium- and large-sized test problems. Also, the efficiency of the proposed MOICA is revealed by comparison with the performance of a non-dominated sorting genetic algorithm (NSGA-II). The computational results demonstrate that the performance of the proposed MOICA is superior to the NSGA-II. Furthermore, a real-world case study is conducted to validate the proposed model. [ABSTRACT FROM PUBLISHER]

In the present study, gold nanoparticles were synthesized in various polymer solutions by means of employing laser ablation technique at the same ablation time. Specifically, gold nanoparticles were synthesized in polyethylene glycol and chitosan solutions, in order to compare the effects of the liquid media which served as stabilizers for particle size and volume fraction of nanoparticles. In addition, this experiment was repeated in distilled water for reference purposes. As the findings indicated, the particle size which was obtained in polyethylene glycol was about 7.49 nm, that is, smaller than those of chitosan solution and distilled water, respectively. In contrast, it was observed that the volume fraction of gold nanoparticles increased in polyethylene glycol in comparison with the other media which indicated an effect on the formation of NPs. On the other hand, Z-scan technique was employed to measure the nonlinear refractive index and nonlinear absorption coefficient of nanofluids containing gold nanoparticles. Consequently, the nonlinear properties of nanofluids pointed to a significant contribution with the number of nanoparticles observed in fluids and both optical nonlinear parameters were observed to increase by means of a prior increase in the volume fraction of Au-NPs in polyethylene glycol solution. [ABSTRACT FROM AUTHOR]

A new Schiff base ligand N,N′-bis(2,4-dihydroxybenzylidene)-1,2-diaminobenzene [=HL] and its Cu(II) complex [Cu(L)] are synthesized and characterized by IR, UV-Vis, NMR, mass spectrometry and elemental analysis. Also, the computational prediction of optimized geometries, IR spectra and NMR chemical shifts is performed using the density functional theory (DFT) method. The DFT optimized geometry of the ligand is not planar, so the three benzene rings are located in separate planes. The phenolic protons are engaged in the intramolecular hydrogen-bonding interactions. In the optimized geometry of the square comlex, dianionic L acts as a tetradentate ligand, which occupies four coordination positions in the N, N, O, O manner. The consistency between the calculated and experimental results confirms the validity of the optimized structures for the HL ligand and its Cu complex. [ABSTRACT FROM AUTHOR]