Radiation pressure effects of focused picosecond light pulses

Picosecond pulses focused on an aluminum foil in a vacuum produced high-velocity negatively charged clouds that were detected on a grid. This is interpreted as an electron cloud recoiling from the radiation pressure.     

Modeling of thermodynamic properties of carrot product using ALO,GWO, and WOA algorithms under multi-stage semi-industrial continuous belt dryer

Engineering with Computers - In this paper, multi-stage continuous belt (MSCB) dryer was used for carrot slices drying. Experiments were performed at three air speeds (1, 1.5, and 2 m/s)...     

Active disturbance rejection and Lyapunov redesign approaches for robust boundary control of plate vibration

In this paper, two approaches, namely active disturbance rejection control (ADRC) and Lyapunov redesign, are utilised to stabilise the vibration of a boundary-controlled flexible rectangular plate in the presence of exogenous disturbances. Based on ADRC, an estimation/cancellation strategy is applied where disturbance is estimated online by an extended state observer (ESO) and cancelled by injecting the output of ESO into the feedback loop. By the Lyapunov redesign, on the other hand, the control law intended for a nominal system is redesigned by adding a (discontinuous) control component that makes the system robust to large uncertainties. Both control algorithms are designed directly based on partial differential equation model of the plate so that spillover instabilities that are a result of model truncation are avoided. The established control schemes are able to stabilise the plate vibration by actuating and sensing only along the plate boundary while accounting for the dynamical effects of Gaussian curvature integral, in-plane membrane force and actuator mass. The stability of each control approach is proven using Lyapunov analysis. The efficacy of each proposed control is illustrated by simulation results.     

Rheological and thermal stability of novel weak gels based on sulfonated polyacrylamide/scleroglucan/chromium triacetate

The present study deals with weak gels based on sulfonated polyacrylamide (SPA)/scleroglucan (SC)/Cr³⁺ with an exceptional thermal stability in electrolyte media. The rheological results showed that on increasing the SC concentration the shear viscosity and storage modulus of the SPA/SC/Cr³⁺ system were increased and the dependence of the storage modulus on frequency became weaker. The yield stress of the SPA/SC/Cr³⁺ system was higher than that of the corresponding SPA/SC system. The thermochemical stability increased with increasing relaxation time. The SPA/SC/Cr³⁺ semi‐interpenetrating network exhibited the lowest viscosity loss in electrolyte media; therefore this system may be a potential candidate for enhanced oil recovery applications. © 2016 Society of Chemical Industry     

A new nickel metal organic framework (Ni-MOF) porous nanostructure as a potential novel electrochemical sensor for detecting glucose

Journal of Porous Materials - A Ni-MOF-based novel electrochemical sensor was synthesized with high surface area of 1381 m2/g, significant porosity of 1.14–9.6 nm and average...     

Computational Fluid Dynamics versus Experiment: An Investigation on Liquid Weeping of Nye Trays

The weeping phenomenon was investigated using some experimental tests and a numerical model. The tests were performed within a 1.22‐m‐diameter pilot‐scale column including two chimney trays and two Nye test trays with an air‐water system. The rates of weeping were measured in the Nye trays with two heights of the weir and a hole area of 5 %. Moreover, the weeping rates in the outlet and inlet halves of the Nye tray and the total weeping rate were calculated. In the next step, an Eulerian‐Eulerian computational fluid dynamics (CFD) technique was used. The results show good agreement between the attained CFD findings and the experimental data.     

Crystallite sizes and lattice parameters of nano-biomagnetite particles

Average crystallite sizes of microbially synthesized pure, metal-, and lanthanide-substituted magnetite (bio-magnetite) were determined for a variety of incubation times and temperatures, substitutional elements and amounts, bacterial species, and precursor types. The intriguing difference between nanoparticle bio-magnetite and chemically synthesized magnetite (chem-magnetite) was that powder X-ray diffraction (XRD) data showed that the bio-magnetite exhibited slightly smaller lattice parameters, however, Raman Spectroscopy exhibited no difference in Fe-O bonding. These results indicate that bio-magnetite likely exhibits a more compact crystal structure with less uncoordinated iron on the surface suppressing negative pressure effects. The bio-magnetite with decreased lattice parameters could have potential technological advantages over current commercial chemically synthesized magnetites.     

Remodeling of a commercial plug-in battery electric vehicle to a hybrid configuration with a PEM fuel cell

In the present research, a commercial battery-powered pure electric vehicle was suitably modified to convert it into a hybrid one integrating a PEMFC stack. The hydrogen supply system to the stack included a passive recirculation system based on a Ventury-type ejector. Besides, in order to achieve an optimum operation of the PEMFC stack, a discrete state machine model was considered in its control system. The inclusion of a rehabilitation operating mode prevented the stack from possible failures, increasing its lifetime. It was verified that for the rated operating point when supplying power to the vehicle (2.5 kW) the hydrogen consumption decreased, and the actual efficiency (47.9%) PEMFC was increased close to 1%. Field tests performed demonstrate that the range of the hybrid electric vehicle was increased by 78% when compared to the one of the original battery electric car. Also, under the tested experimental conditions in hybrid mode, 34% of the total energy demanded by the electric machine of the vehicle was supplied by the PEMFC stack.     

Electrochemical gold deposition from sulfite solution: application for subsequent polyaniline layer formation

Electrochemical gold deposition from sulfite solutions was studied by means of voltammetry, EIS and EQCM. A gold film electrode was used for polyaniline layer formation by electrochemical oxidation of aniline. The standard electrochemical reduction potential of the reaction [Au(SO₃)₂]³⁻ + e⁻ = Au + 2 SO₃²⁻ was determined, and is equal to 0.116 V (vs. NHE). Both solution stirring and temperature increase accelerate the electrochemical reduction of gold, when the electrode potential is below −0.55 V. When the potential is above −0.55 V the electrochemical reduction proceeds via passive layer formation. Our study suggests that the passive layer consists of chemically adsorbed sulfite ions and sulfur. The gold film deposited from sulfite solution is a high quality substrate suitable for conducting polymer layer formation. This technique, where a polymer layer electrode is prepared by thin gold film deposition onto a metal surface and by subsequent polymer layer formation, can be applied in sensor research and technology.