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A microwave-assisted two-steps method was proposed for the facile and fast preparation of silver nanoparticle conductive ink. The nanoparticles in the ink are of multi-sized, which is beneficial to getting higher packing density and better conductivity of the printed/written pattern. The effects of the reaction parameters of microwave and additives on the written pattern resistivity were studied on the basis of scanning electron microscope, X-ray diffraction and surface porosity results. Both of the microwave energy and the addition of PVP as the capping agent were found to be critical for the formation of face-centered cubic silver nanoparticles in the conductive ink. The surface porosity and the pore distribution form were also demonstrated to affect the pattern conductivity. The electrical resistivity or the pattern written with the ink prepared at microwave irradiation time of 90 s was calculated to be 364 μΩ cm. The second step of simple centrifugation process could improve the pattern conductivity effectively. After concentrated the conductive ink for two times, the electrical resistivity of the written pattern reduced from 364 to 77 μΩ cm. The proposed two-steps of microwave combined with centrifugation method is a simple and useful way for the preparation of silver nanoparticle conductive ink that can be used in printed electronics.

A facile one-step microwave approach was employed to synthesize silver nanoparticle (AgNP) conductive ink. The conductive ink contained multi-sized silver nanoparticles. Different particle size distribution can be obtained by adding different amounts of the silver source. The relationship between the conductivity of the direct written pattern using the as-prepared silver conductive ink, the particle packing morphology and the particle size distribution standard deviation was investigated. Among all the samples, conductive ink with a silver weight percentage of 10% can have an optimal electrical resistance of 98 μΩ cm after post-hot/pressure treatment at 100°C and 20 MPa for 10 min. The as-prepared conductive ink is of potential application in printed electronics because the sintering condition of low temperatures is feasible for most kinds of flexible substrate materials.

Silver micro/nanomaterials have attracted a great deal of attention due to their superior physicochemical properties. The atomic migration driven by electromigration or stress-induced migration has been demonstrated to be a promising method for the fabrication of metallic micro-/nanomaterials because of the advantage of simple processing. However, how to realize the controllable fabrication and mass production is still the critical technical problem for the method to be used in large-scale industrial applications. In this paper, the multilayered samples consisted of copper foil substrate, Ti adhesive layer, Ag film, and TiN passivation layer and with arrays of artificial holes on the passivation layer were applied to prepare arrays of Ag micro-particles. For the purpose of controllable fabrication, stress-induced migration experiments combined with finite element simulation were applied to analyze the influence of the passivation layer thickness and the heating temperature on the atom migration and Ag particles growing behavior. And the relationship between size of the fabricated Ag particles and the processing parameters of stress-induced migration experiments were also investigated. As a result, a proper structure size of the multilayered samples and heating temperature were recommended, which can be used for the Ag micro-particles controllable fabrication and mass production.

Using molecular dynamics simulations based on explicit-solvent model, we study migration of polymer-modified nanoparticles through nanochannels coated with polymers. The polymers densely grafted on the spherical nanoparticle and the channel surface form spherical polymer brush (SPB) and planar polymer brush (PPB), respectively. The migration of the neutral polymer-modified nanoparticle is driven by electroosmotic flow (EOF). The effects of the electric field strength and the SPB–PPB interaction on polymer conformations and transport dynamics of the SPB are explored. The migration velocity of the SPB reduces as the interaction between the SPB and the PPB increases. For strong SPB–PPB interaction, the directional migration of the SPB can be triggered only after the electric field strength exceeds a critical value. The high EOF velocity forces the center of mass of the spherical nanoparticle to keep near the central region of the channel due to high shear rate close to the brush–fluid interface. Unlike electrophoresis of charged polymer-grafted spherical particles, the SPB adopts a more extended conformation in the plane perpendicular to the EOF direction.

Current-induced changes of surface morphology in printed Ag thin wires were investigated by current stressing tests and numerical simulation. The samples were printed Ag thin wires on a flexible substrate with input and output pads. Different experimentalresults were obtainedthroughchangingthe current density after current supply and the mechanism of those phenomena were investigated by numerical simulations based on the method of atomic flux divergence. Good agreement between the simulations and experimental results was reached. It was found that electromigration was the main factor that caused the change of the surface morphology. The contribution of thermal migration can be ignored, and the Joule heating lead by the supplied current had a very significant accelerating effect on electromigration. Guidelines for effectively changing the Ag thin wire surface through providing predetermined current density was proposed, which were expected to be useful for improving the electrical reliability and lifetime of printed Ag thin wires in flexible electronic devices.

Solid Al&ndash, air batteries are a promising power source for potable electronics due to their environmentally friendly qualities and high energy density. However, the solid Al&ndash, 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&ndash, air battery with a 4 &mu, m 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&ndash, m 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&ndash, air battery designed for mini-watt devices.

Compared with the traditional fuel vehicle, the pure electric vehicle has excellent characteristics in the emissions and energy use. But its driving ranges are much shorter than the traditional fuel vehicle. It has become a bottleneck problem for the development of electric vehicle. It is difficult to establish the accurate model of driving ranges in the actual working condition. Its main reason is that the influence factors of electric vehicle driving ranges and driving ranges have a non-linear relationship. BP neural network can map the complex non-linear relationship and has strong non-linear fitting ability. Compared the driving ranges of fuzzy control with fuzzy PI control in pure electric vehicle with dual-energy storage system, the results of simulation experiment indicate that the fuzzy PI control can extend the driving rages of electric vehicle. The maximum value of the average error is 2.66% in BP neural network prediction.

Aluminum–air (Al–air) battery is one of the most promising candidates for next-generation energy storage systems because of its high capacity and energy density, and abundance. The polyacrylic acid (PAA)-based alkaline gel electrolyte is used in all-solid-state Al–air batteries instead of aqueous electrolytes to prevent leakage. The optimal gel electrolyte exhibits an ionic conductivity of 460 mS cm −1 , which is close to that of aqueous electrolytes. The Al–air battery peak capacity and energy density considering only Al can reach 1166 mAh g −1 -Al and 1230 mWh g −1 -Al, respectively, during constant current discharge. The battery prototype also exhibits a high power density of 91.13 mW cm −2 . For the battery is a laminated structure, area densities of 29.2 mAh cm −2 and 30.8 mWh cm −2 are presented to appraise the performance of the whole cell. A novel design to inhibit anodic corrosion is proposed by separating the Al anode from the gel electrolyte when not in use, thereby effectively maintaining the available capacity of the battery.

The pure electric vehicle with dual-energy storage system is driven under complex driving states. Owing to its nonlinear model, the fuzzy control is usually used in energy distribution. It is difficult for the conventional fuzzy controller without integral part to eliminate the static errors. Its control effect is not satisfactory. The required power minus actual power is the deviation. The self-adaptive fuzzy PI control adjusts the deviation values through tuning the parameters of PI controller in real time. Its control effect is satisfactory. The results of simulation experiment indicate that the self-adaptive fuzzy PI control is more economical than the fuzzy control under the same driving states.

High-value-added recycling of hazardous waste is a key problem in environmental science and engineering. In previous reports, a hazardous-waste-derived catalyst showed better activity than a catalyst synthesised from pure reagents for the reduction of nitric oxide. The multimetallic nature of hazardous waste was speculated to increase the catalytic activity. In this work, a further investigation was conducted to confirm this speculation. It was found that bimetallic catalysts showed better activity than monometallic ones at 50–200 °C. A bimetallic catalyst removed 75.05% of nitric oxide (990 ppm) at 150 °C, whereas monometallic ones removed only 19.50%. Moreover, the bimetallic catalyst removed 11.46 mmol/g of nitric oxide after 1200 min at 300 °C, which was a much higher concentration than that removed by the monometallic catalyst (2.72 mmol/g). Experimental and simulated Raman spectroscopy revealed that enhanced activity was accompanied by a larger blue shift of the metal band (indicating catalytic centre activity) and a smaller blue shift of the carbon band (indicating reductant stability). In a theoretical calculation, a second metal changed the electron density difference of the catalytic centre and activated the distant reductant, increasing both the low-temperature activity and activity stability. The main result of this study explained the reason bimetallic catalysts outperformed the monometallic ones. Because hazardous waste usually contains bimetallic species, it can be used as a suitable resource for producing effective catalysts.

We carried out coarse-grained molecular dynamics simulations to study the electrostatic adsorption of Janus nanoparticles which consist of oppositely charged hemispheres onto charged surfaces. Films with different conformations were formed by Janus nanoparticles. The effects of charge distributions of Janus nanoparticles and the surface on the film structures and dynamic adsorption behavior were investigated in detail. When the surface is highly charged, Janus nanoparticles tend to form single particles or small clusters. In these cases, the surface charge distribution plays an important role in regulating the process of electrostatic adsorption. When the amount of surface charges is reduced, the effect of charge distribution of Janus nanoparticles becomes significant. The repulsive interactions between Janus nanoparticles determine the aggregation behavior of Janus nanoparticles as well as the shape of adsorption structures, which tends to separate Janus nanoparticles and results in a thin adsorption layer and small clusters. When the number of positive charges on the surface of Janus nanoparticle approaches that of negative charges, Janus nanoparticles aggregate into large clusters close to charged surface. The charge distribution of Janus nanoparticles becomes pronounced in the process of electrostatic adsorption.

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

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.

We report a molecular dynamics study on non-equilibrium dynamics of polyelectrolyte brushes under external electric fields. In this work, the effects of chain stiffness and salt concentration on static and dynamic responses of the brushes are addressed in detail. Our simulations indicate that varying these parameters induce rich electro-responsive behavior of the brushes. The increase of salt concentration results in the enhancement of an opposite electric field formed by non-equilibrium distribution of cations and anions, which resists stretching or shrinkage of grafted chains. At strong positive electric fields, the flexible brushes are more sensitive to the change of salt concentration. When reversing the electric field, the stiff brushes undergo a conformational transition from collapse to complete stretching. At high salt concentrations, dynamic responsive magnitude of the brush thickness to added electric field is strongly reduced. It was found that the fall time for the stiff brush becomes much shorter than that for the flexible brush. Additionally, increasing ion concentration leads to an excess extension or shrinkage of flexible brushes. For strongly stiff brushes, such phenomenon occurs in the presence or absence of salt.

A basic understanding of the transport mechanisms of nanostructures in a polymer brush-modified nanochannel as well as the brush-nanostructure interactions at molecular level is important to design and fabricate emerging smart nano/microfluidic channels. In this work, we report coarse-grained molecular dynamics simulations of the translocation of nanoparticles through a cylindrical nanochannel coated with the polymer brush. The effects of the interparticle interaction and grafting density on the distribution and electrokinetic transport of nanoparticles are addressed in detail. Analysis of the distribution and velocity profiles of nanoparticles from the simulations indicate that the location of nanoparticles along the radial direction and their migration velocity are very sensitive to the change of interparticle interaction. We find complicated transport dynamics of nanoparticles under the influence of various grafting densities. The nanoparticles show markedly different translocation behavior upon increasing the grafting density, which depends on the counterion distribution, free room within the brush, nanoparticle-polymer friction, and brush configuration. Our results may serve as a useful starting point for the transport of nanostructures in polymer-modified channels and help to guide the design of novel smart nanofluidic channels for controlling the migration behavior of nanostructures.

A new kernel based unsupervised clustering algorithm has been proposed. The proposed algorithm is called unsupervised kernel possibilistic clustering algorithm (UKPC), which is an extension of the previously proposed clustering algorithm of unsupervised possibilistic clustering algorithm (UPC). In UKPC, the sample points are mapped into the feature space by the introduced kernel function, and the final clustering partition is obtained by optimizing the objective function of UKPC, which adopts the same clustering rule with UPC clustering model. UKPC has the ability of revealing the non-convex cluster structure because the input data are mapped implicitly into a high-dimensional feature space where the nonlinear pattern now appears linear. The contrast experimental results with UPC and other typical fuzzy clustering algorithms show the better performance of the proposed algorithm.