Interpretive biases for one's own behavior and physiology in high-trait-anxious individuals and repressors.

The experiments reported here were designed to test predictions from a cognitive theory of personality proposed by M. W. Eysenck (1997). According to that theory, many of the observed differences between individuals high in trait anxiety and repressors (individuals low in trait anxiety and high in social desirability) depend on underlying individual differences in cognitive biases. It follows from the theory that high-anxious individuals should have an interpretive bias for their own behavior in social situations, that is, they exaggerate how anxious it is. In contrast, repressors should have an opposite interpretive bias for their own behavior, that is, they underestimate how anxious it is. Evidence consistent with these predictions was obtained in Experiments 1 and 2. Implications of these findings for cognitive theories of personality are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental Study and Numerical Simulation of the Large-Scale Testing of Polymeric Composite Journal Bearings: Two-Dimensional Modeling and Validation

The self-lubricating properties of some polymeric materials make them very valuable in bearing applications, where the lubrication is difficult or impossible. Composite bearings combine the self-lubricating properties of polymeric materials with better mechanical and thermal properties of the fibers. At present, there are few studies about these bearings and their design is mainly based on manufacturers’ experiences. This study includes an experimental and numerical study of the large-scale testing of fiber-reinforced polymeric composite bearings. In the first part of this article, a new tribological test setup for large composite bearings is demonstrated. Besides, a two-dimensional finite-element model is developed in order to study the stress distribution in the composite bearing and kinematics of the test setup. A mixed Lagrangian–Eulerian formulation is used to simulate the rotation of the shaft and the contact between the composite bearing and the shaft. Simulation results correspond closely to the experimental data, and provide careful investigation of the stress distribution in the bearing. In the second part of this article, three-dimensional quasi-static and two-dimensional dynamic models are studied.     

Precision control of a piezo-actuated micro telemanipulation system

Piezoelectric actuators are widely used in micro manipulation applications. However hysteresis nonlinearity limits accuracy of these actuators. This paper presents a novel approach for utilizing a piezoelectric nano-stage as slave manipulator of a teleoperation system. The Prandtl-Ishlinskii (PI) model is used to model actuator hysteresis in feedforward scheme to cancel out this nonlinearity. To deal with the influence of parametric uncertainties, unmodeled dynamics, and PI identification error a perturbation term is added to the slave model and apply a sliding mode based impedance control with perturbation estimation. The stability of the entire system is guaranteed by Llewellyn’s absolute stability criterion. Performance of the proposed controllers is verified through experiments.     

Graft Copolymerization of Styrene‐Maleic Anhydride Onto Poly(Vinyl Chloride) and Its Cross‐linking by Toluene Diisocyanate: Characterization,Thermal, and Mechanical Properties

In this work, styrene‐maleic anhydride (St‐MA) copolymer was successfully grafted onto poly(vinyl chloride) (PVC) by means of chemical method in cyclohexanone medium. In this manner, the effects of various parameters such as total monomer content, monomers ratio, and initiator concentration on the grafting percentage (GP) and acid value (AV) were examined. The graft copolymers were characterized by Fourier‐transform infrared and nuclear magnetic resonance spectroscopy methods. Afterward, the cross‐linking reaction was carried out through MA hydrolysis and condensation reaction between maleic acid and produced diamines, by toluene diisocyanate (TDI) at the presence of hot water. The results showed that the GP and AV of PVC‐g‐(St‐MA) copolymers were considerably higher than those of PVC‐g‐MA and PVC‐g‐St with significant molecular weight. A gel content of 56% was attained with 1 phr TDI in PVC‐g‐(St‐MA) copolymer. The glass transition temperatures and mechanical properties of PVC‐g‐(St‐MA) samples were increased compared to pure PVC. Cross‐linked PVC‐g‐(St‐MA) showed improved mechanical properties than other samples, but the glass transition temperature of PVC backbone in this cross‐linked copolymer was disappeared due to its heavily dense structure. J. VINYL ADDIT. TECHNOL., 25:377–384, 2019. © 2019 Society of Plastics Engineers     

Benefitting from High-κ Spacer Engineering in Balistic Triple-Gate Junctionless FinFET- a Full Quantum Study

In this paper, a numerically comprehensive investigation have been performed in order to propose a high-κ spacer triple-gate junctionless FinFET (HKS     

Effects of cold plasma on the color parameters of Hyssop (Hyssopus officinalis L.) using color imaging instrumentation and spectrophotometer

This research was conducted to evaluate the effects of cold atmospheric plasma treatment on the color of Hyssop (Hyssopus officinalis L.) and also to compare the usage of the spectrophotometer vs the color imaging instrumentation for the evaluation of the treatment on the color parameters. The experiments were investigated at different treatment times of 1, 5, and 10 minutes and the voltage values of 17, 20, and 23 kV. Possible changes of color were evaluated by using CIE L*a*b* values obtained with HunterLab colorimeter and CIE L*a*b* values obtained with a digital still camera (DSC) using digital image processing (MATLAB software). The values of L*, a*, and b* of the samples were obtained using both the methods. The results revealed that the L*, a*, and b* values of the treated Hyssop samples changed with increasing the treatment time and the voltage applied. Evaluating the interaction effects revealed that there was a significant difference in the (−a^*/b^* ) ratio. In addition, the results showed that the effects of all variables on the color parameters were significantly different in the case of the DSC using digital image processing. However, these effects were not significantly different using HunterLab colorimeter except for time variable and interaction effects of a* and (−a^*/b^* ) ratio. The lightest green color and the maximum chlorophyll content loss were observed for 23 kV applied over 10 minutes. Based on the results, the digital image processing can be used as a practical tool to study the variations at the color of dried Hyssop leaves after cold plasma treatment.     

Study of the performance of dry methane reforming in a microchannel reactor using sputtered Ni/Al2O3 coating on stainless steel

In this study, a microchannel reactor was designed, its catalytic performance in dry methane reforming (DRM) was assessed, and the results were compared with those observed in a conventional fixed bed reactor. The catalyst was prepared in two forms, including catalyst pellets and catalyst-coated plate. The microchannel reactor had thin films of Ni/Al₂O₃ coated on stainless steel substrate via radio frequency (RF) magnetron sputtering method in various sputtering times. The fall-off rate of the catalyst-coated plates can be neglected after putting the plates under the high-temperature DRM reaction, due to the formation of firm active catalyst coatings. The performance of the samples was evaluated at different temperatures from 700 to 800 °C, at P = 1 atm, with a CH₄:CO₂ ratio of 1. The results of XRD showed that with increasing the sputtering time, there was an increase in crystallinity. As observed in FESEM images, the sample prepared with 5 min of sputtering was dense and uniform. The results of EDX not only proved the dispersion of the samples observed in XRD and FESEM analysis, but also verified the presence of the utilized elements. The temperature of 800 °C and the sample with 5 min sputtering time were selected as the optimum condition that provided the best performance. Catalytic performance was investigated in fixed bed reactor at the same GHSV; based on the results there were no significant conversions in the fixed bed reactor. The results of the stability test in the microchannel reactor showed a good performance during 30 h on stream. Therefore, Ni/Al₂O₃ thin films had a satisfactory performance in the designed microchannel. Our study shows that this type of reactor has many advantages in terms of performance, compactness, and economic concerns.     

An Investigation of Mechanical Properties of Polyurethane Nanocomposites with Various Silicas: Experimental Study and Modeling of Finite Deformation Response

It is well-known that polymer nanocomposites can bring about superior mechanical, thermal, optical, physical, and chemical properties in comparison with pure polymers. In this study, different contents of unmodified silica nanoparticles (Si-Un), surface modified nano-silica by octylsilane (Si-OS), and surface modified nano-silica by polydimethylsiloxane (Si-PDMS) are added to the polyurethane (PU) matrix and their effects on the physical properties of the polymer examined. The experimental results indicate that most of the nanocomposites have a higher tensile strength and elongation. In addition, hyperelastic energy function models have been used to model the stress-strain relation of the nanocomposites. In this study, Mooney-Rivlin, neo-Hookean, Rivlin general polynomial, and Davies-De Thomas (DDT) models have been investigated, possessing respectively, two, one, eight, and three constants to be determined. The differential evolution (DE) optimization method, a strong heuristic optimization algorithm, has been used to find the constants; in which the absolute summation of the differences between the models’ predictions and experimental data is taken into account as the objective function and the models’ constants are considered as the decision variables. Moreover, equation constants are found by using regression, an indicator of DE optimization superiority. The results show that even though the Rivlin general polynomial model provides the most accurate prediction, the DDT model, consisting of three constants, can be considered as the most acceptable one.