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Solid Al-air batteries are a promising power source for potable electronics due to their environmentally friendly qualities and high energy density. However, the solid Al-air battery suffers from anodic corrosion and it is difficult to achieve a higher specific capacity. Thus, this work aims at suppressing the corrosion of Al anode by adding an electrospun Al2O3 interlayer on to the surface of the anode. The Al2O3 interlayer effectively inhibits the self-corrosion of the Al anode. Further, the effects of the thickness of the Al2O3 film on corrosion behavior were investigated. The results showed that the Al-air battery with a 4 μm Al2O3 interlayer is more suitable for a low current density discharge, which could be applied for mini-watt devices. With a proper thickness of the Al2O3 interlayer, corrosion of the anode was considerably suppressed without sacrificing the discharge voltage at a low current density. The Al-air battery with a 4 μm Al2O3 interlayer provided a significantly high capacity (1255 mAh/g at 5 mA/cm2) and an excellent stability. This wo presents a promising approach for fabricating an inhibiting corrosion interlayer for solid Al-air battery designed for mini-watt devices. [ABSTRACT FROM AUTHOR]

In this paper, the self-assembly process of diblock copolymers confined in multi-walled cylindrical nanotubes is systematically investigated using a molecular dynamics (MD) method. The dependence of resultant morphologies on the degree of confinement and on the interaction strength between nanotubes and copolymers is studied comprehensively. When the wall surfaces are not preferential, results indicate that geometric confinement significantly influences copolymer conformations. In addition, the thickness of the helical lamellar structure increases with interaction strength and confinement size. In cases where the nanotubes are strongly attracted to one copolymer block, the confinement effect weakens as geometric space increases. Findings explain the dependence of chain conformation on the degree of confinement and the strength of surface preferences. [ABSTRACT FROM AUTHOR]

We study 30-nm chromatin fibre restricted in a nanofluidic channel with square cross-section using Monte Carlo (MC) simulations. The chromatin fibre is modelled as cylinders-on-a-string with six alterable angles. The effects of the channel width and Emax on the configuration of the chromatin fibre are investigated in detail. Our results show that the channel width has a considerable influence on conformational characteristics of the chain. It is found that at large Emax, the chromatin fibre undergoes a conformational transition from stretched state to coiled state with increasing the channel width. Additionally, the influence of the channel width is lowered with enhancing Emax. At small values of the channel width, the chains for different Emax exhibit a similar structure, namely, a stretched conformation. [ABSTRACT FROM AUTHOR]

Drying plays an important role in the postharvesting process of grain. To ensure the quality of the dried grain and improve the intelligent level in drying process, a digital simulation of corn drying machine system based on a virtual instrument was established for 5HSZ dryer, automatically control the air temperature, and predict the discharging speed of grain and so forth. Finally, an online measurement and automated control software of grain parameters were developed to provide the changes of moisture, temperature, humidity, and germination rate in the process of drying. The study carried out in the actual processing showed that it can meet the requirements of the actual drying operation, effectively control the stability of the grain moisture, and keep the dry food quality. [ABSTRACT FROM AUTHOR]

Using Brownian dynamics simulations, we study the effect of the charge ratio, the surfactant length, and the grafting density on the conformational behavior of the complex formed by the polyelectrolyte brush with oppositely charged surfactants. In our simulations, the polyelectrolyte chains and surfactants are represented by a coarse-grained bead-spring model, and the solvent is treated implicitly. It is found that varying the charge ratio induces different morphologies of surfactant aggregates adsorbed onto the brush. At high charge ratios, the density profiles of surfactant monomers indicate that surfactant aggregates exhibit a layer-by-layer arrangement. The surfactant length has a strong effect on the adsorption behavior of surfactants. The lengthening of surfactant leads to a collapsed brush configuration, but a reswelling of the brush with further increasing the surfactant length is observed. The collapse of the brush is attributed to the enhancement of surfactants binding to polyelectrolyte chains. The reswelling is due to an increase in the volume of adsorbed surfactant aggregates. At the largest grafting density investigated, enhanced excluded volume interactions limit the adsorption of surfactant within the polyelectrolyte brush. We also find that end monomers in polyelectrolyte chains exhibit a bimodal distribution in cases of large surfactant lengths and high charge ratios. [ABSTRACT FROM AUTHOR]

We conducted coarse-grained molecular dynamics simulations to study the responsive behaviors of polyampholyte brushes (PABs) under external electric fields. The effects of charge sequence, chain rigidity and electric field strength on the conformational transition and local structures of grafted chains were addressed systematically. Without electric field, the calculations indicate that the thickness of the PABs is smaller compared to polyelectrolyte brushes (PEBs). The presence of electric field leads to inconsistency of densities between negatively and positively charged monomers except for the alternating brush. Counterions from the PABs can diffuse inside or outside the brush. Unlike the PABs, to separate the polyelectrolytes and their counterions the electric field needs to overcome the osmotic pressure of counterions. The critical field which induces the extension of the flexible PABs is much larger than the PEBs. Meanwhile, it was also found that the critical field which induces the collapse of the PABs decreases as the block length increases. In the limit of strong field studied, the chains with longer blocks are in a local extended state. For diblock brushes, once oppositely charged blocks in a single chain are separated, the chain will become straighter due to strong electrostatic repulsion in intrablock. [ABSTRACT FROM AUTHOR]

We investigate polyelectrolytes end-grafted on two apposing walls using molecular dynamics simulation techniques. Monovalent and trivalent counterions are explicitly treated. Under normal compression, the osmotic pressure is examined in detail by decomposing it into various virial terms. It has been found that at small wall separations the increase in the osmotic pressure can be ascribed to the increase in the short-range virial term. At large wall separations, a negative osmotic pressure is observed in trivalent systems. Moreover, we study the effect of lateral shear on the density profiles of monomers and counterions, the net charge distribution, the local pressure tensor, the degree of interpenetration and the friction coefficient. At large shear ratios, the electrostatic interactions are weakened at the interface between two brushes. It is worth noting that although the magnitudes of the normal and shear stress components for the trivalent case are significantly lesser than those for the monovalent case, the friction coefficient is larger in the trivalent systems. [ABSTRACT FROM AUTHOR]