Fuzzy logic based device to implement a single CAD model for a laser diode based on characteristic quantities

In this study, a single modelling approach based on fuzzy logic (FL) device is designed for a quantum-well (QW) laser diode to obtain the characteristic quantities and their dependences on wavelength and injection currents. The fuzzy rules are compiled using the input variables which are namely the wavelength and the injection currents, while the output parameters are the modal gain difference, the effective refractive index difference and alpha (α) parameter (linewidth enhancement factor). The suggested approach provides fast and reliable predictions which can prevent the engineers from rigorous experiments/calculations. The FL device provides the predictions of modal gain difference, effective refractive index difference and alpha parameter against the wavelength and the injection currents within the accuracy level of 90–99.9%.     

A novel vicinal dioxime and its homo- and heterotrinuclear complexes

The new vicinal dioxime N,N-bis(2-benzimidazolylmethyl)diaminoglyoxime (H₂L) has been prepared by reacting 2-aminomethylbenzimidazole with cyanogen-di-N-oxide. Reaction of H₂L with Cu^II and Co^III salts and appropriate reagents gave mono- and trinuclear complexes, [Cu(HL)₂], [Cu₃(L)₂(phen)₂], [Co(HL)₂LCl] (L=2,6-lutidine), [Co(LBF₂)₂LCl] and [Cu₂(ClO₄)₂Co(LBF₂)₂LCl](ClO₄)₂, which were characterized by i.r., ¹H- and¹³ C-n.m.r., m.s. and elemental analyses.     

Synthesis and structural studies of (2 E ,3 E ,6 R ,9 E ,11 E )-6-isopropenyl-3,6,10-trimethyl-5,8-dioxa-4,9-diazadodeca-3,9-diene-2,11-dione dioxime, ligand and its Mono-, homo, and heterodinuclear copper(II)/nickel(II) complexes

This article describes the synthesis of a new (2E,3E,6R,9E,11E)-6-isopropenyl-3,6,10-trimethyl-5,8-dioxa-4,9-diazadodeca-3,9-diene-2,11-dione dioxime (H₂hmdm), and its mono-, homo, and heterodinuclear copper(II)/nickel(II) complexes. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). The Cu(H₂hmdm), molecule coordinates to the second copper(II) ion through the oximate oxygens to afford a binuclear structure doubly bridged by the oximate groups in the cis arrangement. In the dinuclear complexes, in which the first Cu^II ion was complexed with nitrogen atoms of the oxime and imine groups, the second Cu^II ion is ligated with the 1,10-phenanthroline nitrogen atoms. Ligand and its mononuclear copper(II), homo and heterodinuclear copper(II)–nickel(II) complexes of (H₂hmdm) were characterized by elemental analyses, magnetic moments, ¹H-n.m.r. and ¹³C-n.m.r., i.r., and mass spectral studies. The data support the proposed structure of H₂hmdm and its complexes.     

Synthesis and Structural Studies of 2-(hydroxyimino)-1-methylpropylideneamino-phenyliminobutan-2-one Oxime, Ligand and its Complexes with Cu(II) and Ni(II)

A new ligand incorporating a dioxime moiety, (2E,3E)-3-[(2-{[(1E,2E)-2-(hydroxyimino)-1-methylpropylidene]amino}phenyl)imino]butan-2-one oxime, (H₂Phmdo) (3) has been prepared by reacting 2,3-butanedionemono-{O-[4-(1-methyl-2-oxo-propylideneaminooxy)-2,3-bis-(1-methyl-2-oxo-propylideneaminooxy-methyl)-but-2-enyl]-oxime} (2) with 1,2-phenylenediamine. Mono-, di- and trinuclear copper(II) and/or nickel(II) complexes of H₂Phmdo were characterized by elemental analyses, magnetic moments, ¹H-n.m.r. and ¹³C-n.m.r., i.r. and mass spectral studies. The mononuclear copper(II) and nickel(II) complexes of H₂Phmdo were found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N). In the dinuclear complexes, in which the first Cu^(II) or Ni^(II) ion was complexed with nitrogen atoms of the oxime and imine groups, the second Cu^(II) ion is ligated with dianionic oxygen atoms of the oxime groups and are linked to the 1,10-phenanthroline nitrogen atoms. The data support the proposed structure of H₂Phmdo and its complexes.     

Testing of nonlinear electrofrictiophoresis in agarose gel

It was theoretically predicted earlier that if a periodic force without constant component is applied to a particle, then the particle can produce a directed drift in some direction. The effect is named nonlinear electrofrictiophoresis, because it is crucial for its appearance that the friction force depends on the particle's velocity in a nonlinear manner. We test a possibility to observe this effect when a mixture of fragments of DNA (the DNA ladder) moves in the agarose gel. For this purpose, we study the nonlinear characteristics of a DNA ladder movement in the gel. The gels with the ladder were run under various electric field strengths. It was found that the friction coefficient for each DNA fragment in the ladder depends on the migration velocity, suggesting that energy dissipation during migration is a nonlinear function of velocity. This nonlinearity makes the system under consideration suitable for observing nonlinear electrofrictiophoresis. A possible velocity of directed drift under periodic electric drive without constant component was estimated numerically for experimentally observed dependencies. The velocity appeared to be comparable with that of migration under a constant field of moderate strength. A possible mechanism of energy dissipation during movement of DNA through the gel is discussed.     

Determination of thyroxine hormone by luminol chemiluminescence

A chemiluminescence (CL) flow system for determination of thyroxine (Thy) is presented. It is based on the catalytic effect of cobalt(II) on the CL reaction between luminol and hydrogen peroxide. The iodinated chemical structure of Thy causes a heavy atom effect. The luminol CL signals show significant quenching by Thy. The calibration graph for Thy is linear for 15-70 μg ml⁻¹ and the 3σ detection limits are 27 μg ml⁻¹ for d-Thy and 23 μg ml⁻¹ for l-Thy.     

Synthesis and photopolymerizations of new phosphonated monomers for dental applications

Three novel phosphonated methacrylate monomers have been synthesized and studied for use in dental applications. Two of the monomers were synthesized from the reactions of glycidyl methacrylate (GMA) with (diethoxy‐phosphoryl)‐acetic acid (monomer 1 ) and (2‐hydroxy‐ethyl)‐phosphonic acid dimethyl ester (monomer 2 ). These monomers showed high crosslinking tendencies during thermal bulk and solution polymerizations. The third monomer (monomer 3 ) was prepared by the reaction of bisphenol A diglycidylether (DER) with (diethoxy‐phosphoryl)‐acetic acid and subsequent conversion of the resulting diol to the methacrylate with methacryloyl chloride. The homopolymerization and copolymerization behaviors of the synthesized monomers were also investigated with glycerol dimethacrylate (GDMA), triethylene glycol dimethacrylate (TEGDMA), and 2,2‐bis[4‐(2‐hydroxy‐3‐methacryloyloxy propyloxy) phenyl] propane (bis‐GMA) using photodifferential scanning calorimetry at 40 °C using 2,2′‐dimethoxy‐2‐phenyl acetophenone (DMPA) as photoinitiator. Monomer 1 showed polymerization rate similar or greater than dimethacrylates studied here but with higher conversion. The maximum rate of polymerizations decreased in the following order: 1 ～TEGDMA>GDMA～bis‐GMA～ 3 > 2 . A synergistic effect in the rate of polymerization was observed during copolymerizations. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2290–2299, 2008     

Control of chaotic systems using targeting by extended control regions method

In this work, the previously proposed extended control regions (ECR) algorithm for targeting is improved by using individual neural networks for each activation region. The improved version, which exploits the short time predictability of the chaotic system more efficiently, gives better performance with respect to training time and average reaching time while maintaining the advantages of the previous method. Moreover, the simulation results revealed that the meaningful number of activation regions of the controller using improved ECR is nearly linearly related with the prediction horizon of the chaotic system to be targeted, which can be used as a criterion for choosing the number of activation region.     

Parametric dependencies for photoacoustic leak localization

Unintended gas or liquid leaks from manufactured components or manufacturing systems may be detrimental to consumers, manufacturers, and the environment. Thus, leak testing is important for quality, safety, and environmental reasons. This paper describes parametric dependencies for photoacoustic leak localization. The technique is based on the interaction of 10.6-micrometer radiation from a carbon dioxide (CO2) laser and a photoactive tracer gas, sulfur hexafluoride (SF6). For the current investigations, acoustic signals are generated by scanning a laser beam at high speed through gas plumes formed above calibrated leaks. These signals are remotely measured with a four-microphone linear array and analyzed using Bartlett and minimum-variance-distortionless (MVD) matched-field processing (MFP) techniques to determine leak location. This paper extends prior work in photoacoustic leak testing through (i) use of more signal frequencies; (ii) parametric study of four different laser scan rates; and (iii) examination of mismatch between the actual acoustic environment and the propagation model used in the MFP; and (iv) presentation of leak localization results on a curved surface. For a 12-watt CO2 laser exciting the small SF6 gas plume produced by a one-cm3-per-day leak with microphones placed 0.41 m from the leak location, root-mean-square localization uncertainties as small as +/-0.5 mm on a line scan of 0.46 m can be achieved when the largest possible number of signal frequencies fall in a measurement bandwidth of approximately 70 kHz.