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Iron containg hexagonal mesoporous silica particle (Fe-MCM-41) was prepared and adopted into carbonyl-iron (CI) based magnetorheological (MR) suspension as an additive to improve the sedimentation problem of the CI based MR fluid. Structural properties and morphology of the synthesized Fe-MCM-41 particles were observed using SEM. Their MR properties such as oscillation characteristics and flow response (shear stress and shear viscosity) were examined via a rotational rheometer in parallel plate geometry equipped with a magnetic field supplier under external magnetic field strengths ranging from 0 to 257 kA/m. The addition of Fe-containing mesoporous particles into CI suspension was found to improve not only MR behaviors but also sedimentation problem of the CI based MR fluid.

We reported a simple, high yield and large-scale preparation method for silver nanoparticles. Silver nanoparticles with 8–13 nm in diameter were successfully synthesized by silver nitrate as raw material, sodium borohydride as reducing agent, dispersan-5040 (polycarboxylate sodium salt) as surface modifier in aqueous solution. The effects of sodium borohydride and dispersan-5040 on the morphologies of silver nanoparticles were investigated. Further, the conductive inks were prepared with as-synthesized silver nanoparticles as conductive fillers in the presence of deionized (DI) water and additives. The effects of conductive fillers and additives on the pH, conductivity, surface tension and viscosity of the inks were investigated. The conductive patterns were fabricated by inkjet printer and their performances were studied. The sheet resistances of the printed pattern with seven-layer was 1.2 $\mathrm{\Omega }/\square$ when the printed pattern was heat-treated at 120${}^{\circ }$C for 60 min. We succeeded in printing a simple conductive circuit on photographic paper, which can light three 0.06 W LED beads. The successful fabrication of the functional circuit proves the feasibility of the ink and provides some ideas for future paper-based circuits.

ZrO₂ is a kind of inorganic material with high hardness, high tenacity, antiwear, corrosion, and resistance, therefore it is regarded as an ideal nanolubricant material. But untreated ZrO₂ nanoparticles are reunited in the lubricant medium instead of monodisperse because the consistency is poor between the material surface and lubricant, which restricts its application as a nanolubricant additive. Through theoretical analysis, this paper designed that the surface of ZrO₂ nanoparticles was modified with silicon coupling agent, and it was changed to lipophilic surface, so it was possible to be a monodisperse system in the lubricant. The modified spherical nanoparticles of ZrO₂ were dispersed in the lubricant and they could play a molecular bearing part in lubricating media. When the friction surface reached a certain load and temperature, once the metal surface produces the deficiency, physical adsorption and chemisorption on the metal surface would be produced because of high nano-ZrO₂ particle activity, and even the N atom in the particle surface silane tends to be absorbed to the metal surface to form chelate compound, and make ZrO₂ particles enrich to defective locations of the metal surface. Then, a self-repairing lubricated membrane in the friction surfaces was set up, and it can play the function in the antifriction, antiwear, and surface dynamic self-repair.

The surface modification mechanism of polyvinyl chloride (PVC) by ozonation was investigated to study the selective hydrophilization of PVC surface among other plastics. Infrared analysis confirmed the increase of hydrophilic groups. XPS analysis revealed that the increase was due to the structural change in chlorine group in PVC to hydroxylic acid, ketone, and carboxylic groups by ozonation. This chemical reaction by ozone could occur only for polymers with chlorides in its structure and resulted in the selective hydrophilization of PVC among various polymers.

Phytic acid (PA) and 3-aminopropyltrimethoxysilane (APTMS) were selected as organic additives and respectively doped into Na₂SiO₃-NaOH electrolyte to prepare ceramic coatings on AZ31B Mg alloys by Plasma Electrolytic Oxidation (PEO) method. The influences of two additives on corrosion resistance of the PEO coatings were compared. The microstructure, composition and corrosion resistance of the PEO coatings were examined by SEM, EDX, XPS, XRD, potentiodynamic polarization test and EIS measurement. The results indicated that each additive increased both the coating thickness and corrosion resistance. However, the PA-doped PEO coating achieves larger thickness but exhibits worse corrosion resistance than the APTMS-doped PEO coating due to larger pore size and looser microstructure.

Disparate industry bodies across the planet use pallets for storing large and heavy objects. Pallets provide an assurance of safe handling of material (cargo) and storage of material in a damage-free environment. In this work, an attempt has been made to analyze and investigate making pallets out of ULTEM 9805 using the latest additive techniques (FDM). The maximum deflections and von Mises stresses are analyzed for the disparate boundary conditions indicating the possible alternatives or loads to be used. Study of surface (morphology) and characteristics was done in order to establish the relationship between pallet surface and its application. The factors of load, maximum and minimum values, ascertained in each stage are 168.15, 522.22, 215.31 and 316.79 kPa as well as 18.77, 6.7, 1.2 and 35.84 kPa for the floor, rack, forklift and conveyor load supports, respectively. A cross-hatched design causes a rise in capacity of the shear factor owing to the length of the span being in correlation with rectilinear fill. The filament of surface, made of ULTEM 9805, exhibits a level of roughness of 43.14 μm on the pallet surface indicating better holding capacity and grip. A 9^∘ peak shift is comprehended with respect to XRD, indicating a compressive residual factor measured at 76.47 MPa.

In this study, lemon juice at different concentrations as a new additive was poured into the bath of the anodizing process to enhance the mechanical properties of the manufactured aluminum oxide layers. X-ray diffraction (XRD) and field-emission scanning electron microscopy were utilized to detect formed phases and microstructure, respectively. To investigate mechanical properties, microhardness, indentation toughness, and wear tests of various aluminum oxide layers were performed. The XRD patterns showed a crystalline phase of $\gamma$-Al₂O₃ for all oxide layers. The microhardness of modified layers increased up to 62.2% compared to the unmodified layer. However, by increasing the additive concentration to 2.5 vol%, the hardness decreased. This was based on increasing the pore size of layers. The lowest friction coefficient with a value of 0.53, the lowest wear rate, and the highest indentation toughness was also related to the modified aluminum oxide layer when the concentration of the additive in the bath was 0.3 vol%. For this modified layer, the value of COF/$H$ was the lowest, and the pore size of 50 nm was the lowest among the layers.

Doubly stochastic effects are effects in which an optimization of both multiplicative and additive noise intensities is necessary to induce ordering in a nonlinear system. I review recent achievements in the investigation of these effects and discuss two phenomena: doubly stochastic resonance and noise-induced propagation in monostable medium. Finally I discuss possible experimental implementations of these phenomena.

Two polyurethanes of different molecular weights were prepared by the copolymerization of phenyl diisocyanate and diisopropyl tartrate. The polyurethanes having terminal isocyanate groups were reacted with 3-aminopropyl silica gel to afford two chiral stationary phases. The of the two polyurethanes were 4057 g/mol and 6442 g/mol. The polyurethanes and the corresponding chiral stationary phases were characterized by FT-IR, ¹H NMR and elemental analysis. The loading capacities of the polyurethanes on silica gel were 0.68 mmol units/g and 0.61 mmol units/g, respectively. The separation performance and the influence of additives, triethylamine and trichloroacetic acid, on the separation of chiral compounds were investigated by HPLC. The chiral stationary phase prepared from polyurethane with of 4057 g/mol demonstrated better enantioseparation capability than that with of 6442 g/mol. Additionally, it was found that the addition of triethylamine and trichloroacetic acid in the mobile phases significantly improved the enantioseparation for these two chiral stationary phases.

As the portable electronics industry continually drives electronic assemblies to higher functionality in smaller form factors, material compatibility and thermal dissipation issues are becoming considerably more acute. Most of the current approaches attempt to marry conventional materials technologies in order to achieve as much leverage as possible out of the established infrastructure. However, concurrent engineering of reliable, high-density electronic assemblies will require the introduction of a new material technology.

A novel base technology that is applicable to all of the major packaging and redistribution elements in an electronic module is presented. A single family of polymer/metal composite conductors can be used for chip packaging redistribution layers, multichip module or multilayer PWB interconnects, and SMT assembly. High-density multilayer circuits with landless blind and buried vias can be fabricated by filling the conductor paste into photoimaged dielectrics and thermal processing. Via layers are prepared directly on the inherently planarized circuit layer in an identical fashion. Building up layers sequentially in this manner results in multilayer circuits built on a single substrate layer and minimizes the number of interfaces between dissimilar materials. Because these composite materials are applied in an additive fabrication method, metal substrates can be employed for high thermal dissipation and excellent CTE control over a wide temperature range. Two variants of the composite conductor can successfully replace solder for surface mount and chip on board assembly. These reliable, highly-thermally and electrically conductive materials are compatible with the standard metal finishes of conventional technologies and can be adopted piecemeal as desired; however, the largest reliability and cost benefit is realized when all of the elements are used in conjunction with one another.

The conductor materials are based on interpenetrating polymer and metal networks that are formed in situ from metal particles and a thermosetting flux/binder. The metal network is formed when the alloy particles melt and react with adjacent high-melting point metal particles. Interaction also occurs between the alloy particles and pad, lead or previous trace metallizations provided they are solderable by alloys of tin. The new alloy composition created by the interdiffusion process within the bulk material has a higher melting point than the original alloy and thus solidifies immediately upon formation. This metallurgical reaction, known as transient liquid phase sintering, is facilitated by the polymer mixture. Integration of the polymer and metal networks is maintained by utilizing a thermosetting polymer system that cures simultaneously with the metallurgical reaction. Although similar in concept and performance to cermet inks, these compositions differ in that their process temperatures are compatible with conventional printed wiring board materials and that the polymeric binder remains to provide adhesion and fatigue resistance to the metallurgical network.

The CaF₂–4LiF additive was added into SrTiO₃ ceramics in order to decrease the sintering temperature for compact pulse power application. The crystalline structure, microstructure and energy storage performance of sintered ceramics were studied. Incorporating CaF₂–4LiF additive to SrTiO₃ ceramics contributes to a notably enhancement of the energy storage density. The great enhancement in energy storage density occurred due to the notable increase in breakdown strength and the refinement of microstructure. With 2 at% additive, the samples exhibited an average breakdown strength of 31.8 kV/mm, and an energy storage density of 1.212 J/cm³ which is about 1.4 times higher than pure SrTiO₃.

The hardness, toughness and sum of cracks measurement of fine-grained WC-Co hard metals were studied. Thirty commercial and experimental hard metal grades with different additives such as boron carbide (B₄C), vanadium carbide (VC), chromium carbide (Cr₃C₂) and silicon carbide (SiC) were prepared in a commercial sinter HIP furnace. Physical, mechanical and microstructure properties were investigated to build up a representative hardness/sum of cracks measurement band. This band was then used to estimate the most effective sintering temperature and the amount of each additives. Afterwards, influence of grain growth inhibitors in optimum condition were compared. The results showed that the grades, doped with B₄C and VC as growth inhibitor exhibits more hardness than other comparable doped alloys. However, Cr₃C₂ is favorable in toughness improvement.