Showing papers in "Powder Technology in 2009"

TL;DR: In this paper, the authors summarize recent development in research on synthesis and characterization of stationary nanofluids and try to find some challenging issues that need to be solved for future research.

TL;DR: In this article, polystyrene was grafted onto the surface of ZnO nanoparticles to improve the dispersion of the particles and to reduce their photocatalytic activity.

TL;DR: In this article, two types of polysilicon nanoparticles were used in oil fields to improve oil recovery and enhance water injection respectively, and the results showed that nanoparticles are effective agents for enhancing water injection capability or improving oil recovery.

TL;DR: In this paper, two formulas for explicitly evaluating drag coefficient and settling velocity of spherical particles, respectively, in the entire subcritical region were proposed for Reynolds numbers up to 2 × 105.

TL;DR: In this article, a mathematical model combining discrete element method (DEM) with Computational Fluid Dynamics (CFD) is presented to describe dense medium cyclone (DMC) flow system.

TL;DR: In this paper, the effect of moisture content on four pharmaceutical powders (an active pharmaceutical ingredient (API), Aspartame, Hydroxypropyl Methylcellulose (HPMC), and Respitose ML001) has been investigated.

TL;DR: In this article, a double injection of the CaCl2 and NH4HCO3 solutions with molar ratio of 1:1 at 30-80°C was performed to obtain the formation of the aragonite whiskers at 80°C.

TL;DR: In this paper, the authors used a variety of techniques that tested powders under different stress states, ranging from static to dynamic, and found that characterization techniques that were more dynamic such as fluidized bed expansion were best suited for predicting the fluidization performance while characterization techniques such as cohesion were better for predicting agglomeration.

TL;DR: In this article, the discrete element method (DEM) is used to assess powder flow from hoppers and the results are compared to widely-used hopper design charts, which delineate mass-flow and funnel-flow behavior based on the hopper wall angle and a given set of material properties.

TL;DR: In this paper, the size reduction mechanical energy was measured for switchgrass (Panicum virgatum L), wheat straw (Triticum aestivum L.), and corn stover (Zea mays L.) in an instrumented hammer mill.

TL;DR: In this paper, an experimental work on the measurement of effective electrical conductivity of aqueous suspensions of aluminum oxide nanoparticles (nanofluids) was performed both as a function of volume fraction and temperature.

TL;DR: In this paper, the Discrete Element Method (DEM) is applied to simulate a single pitch screw conveyor with periodic boundary conditions to predict the performance of screw conveyors in terms of variations of particle speeds, mass flow rate, energy dissipation and power consumption, due to changes in the operating conditions.

TL;DR: In this paper, a submersible accelerometer probe was used to measure the relative ultrasonic energy field in the liquid for various ultrasonication methods, and the dispersion of ZnO was found to proceed by a fragmentation process, with minimum achievable particle size in the range 50 to 300 nm.

TL;DR: In this paper, polystyrene/nano-SiO 2 composite microspheres with core-shell structure were successfully synthesized in a Pickering emulsion route using nano-SiOs 2 particles as stabilizers, which were organically modified by methacryloxypropyltrimethoxysilane (MPTMS) which containing a reactive C C bond.

TL;DR: In this article, a detailed analysis of the die fill process on high speed rotary tablet production presses is presented, where the powder is deposited into the die under the effect of the gravity.

TL;DR: In this paper, the agglomeration behavior of silica particles under different milling and stability conditions is presented, and the particle breakage behavior in the nanometer range is discussed.

TL;DR: In this paper, high energy ball milling was used to produce a nanostructured Al matrix composite reinforced by submicron α-alumina particles, which can increase the hardness of powder due to a nano-structured matrix and oxide dispersion strengthening.

TL;DR: In this paper, the antibacterial activity of calcined powder at 300 and 500°C was studied in the presence and in the absence of UV irradiation against Escherichia coli as a model for Gram-negative bacteria.

TL;DR: In this article, the applicability of TiO2/Au composite particles, which probably have the plasmon resonance effect, on FTO-glass substrate of the working electrode of a dye-sensitized solar cell (DSSC), was investigated.

TL;DR: In this paper, the influence of the powder/binder combinations on the rheological behavior and thermal stability of carbonyl iron and stainless steel powder injection molding (PIM) feedstocks was investigated with a combined experimental and simulation study.

TL;DR: In this paper, experiments were carried out on the rheological behavior of ethylene glycol (EG) based titanate nanotubes (TNT) nanofluids containing 0.5, 1.0, 2.0 and 8.0 wt.% TNT at 20-60 °C.

TL;DR: In this paper, the effects of particle size distribution, uniformity of the distribution and specific surface area (SSA) on the strength of cement were studied using PC 42.5 R.

TL;DR: In this article, the effects of pH value on the composition, structure, morphology, and phase transformation of aluminum hydroxides prepared by chemical precipitation were studied, and it was shown that the pH value affects not only the morphology but also the microstructures of final decomposition products.

TL;DR: A facile and rapid microwave-assisted combustion method was developed to synthesize the nanocrystalline Co 3 O 4. as discussed by the authors suggested that application of microwave heating to produce the homogeneous porous Co 3 o 4 was achieved in a few minutes.

TL;DR: In this paper, the authors present the study of wet granulation of microcrystalline cellulose powder, MCC (Avicel PH101) using high-shear mixer granulator.

TL;DR: A methodology combining theoretical and experimental techniques for analyzing the growth of granules in a fluidized bed granulator was developed in this paper, which combines several key features of this complicated process: (i) population balancing (PB) of growth of different granules; (ii) hydrodynamic modeling of the gas-solid mixture flow using Computational Flow Dynamics (CFD); (iii) modeling of contact mechanics and granule formation; (iv) the Stokes number analysis for calculation of successful collisions; (v) well-controlled experimental study of the wet granulation.

TL;DR: In this article, the authors examined the formation, breakage and re-growth of flocs formed by kaolin or the mixture of kaolin and humic acid with aluminum sulfate (alum) or polyaluminum chloride (PACl).

TL;DR: In this article, a correlation between the breakage parameters of pharmaceutical powders and their mechanical properties (hardness, Young's modulus and fracture toughness) that are determined from indentation experiments was established.

TL;DR: In this paper, a novel approach to simulating triaxial tests with DEM using circumferential periodic boundaries has been developed by the authors, and the results of the DEM simulation are used to explore the particle-scale mechanics during the load reversals.

TL;DR: In this article, mesoporous silica spheres with controllable particle size were synthesized in mixed ethanol-water solvent and three kinds of release fluids, simulated intestinal fluid, simulated body fluid, and simulated gastric fluid, were used to investigate drug release.