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Electromagnetic fields can generate orientation-dependent, long range interactions between colloidal components that direct their into highly ordered structures, such as small ordered clusters, chains, and large crystalline lattices. While much effort has been devoted to exploring the assembly of spherical colloids, few reports have investigated the directed assembly of non-spherical particles with Janus or patchy morphologies. Here, we use photolithographic techniques to fabricate a wide range of anisotropically shaped patchy particles and follow their in liquid suspensions under the influence of electric and magnetic fields. We analyze the assembly of several types of patchy particles across a range of field parameters and fluid compositions, and report a number of distinct, well-ordered, architectures including cylindrical, prismatic, and staggered chains. The structures assembled from anisotropic patchy components provide a glimpse into the range of architectures that can be created by combining field directed with rationally designed particles. By using numerical simulations to model the electric and magnetic field interactions between these particles, we interpret the results of the assembly process and explain how they can be controlled by the position of the metal facet, the frequency (for AC fields), or magnetic susceptibility of the medium. The resulting structures, and similar ones produced through the field-directed assembly of patchy anisotropic particles, can possess unique electrical and optical properties and may have potential applications in a number of future technology applications such as microactuators, metamaterials and multiferroic materials.

In this work, calcium ethoxide is proposed as a catalyst for the transesterification of soybean oil to biodiesel with methanol and ethanol. First, calcium ethoxide was synthesized through a calcium reaction with ethanol. Then, its physical and chemical characteristics were determined using instrumental methods such as Brunauer-Emmett-Teller surface area measurements, scanning electron micrographs, and particle size distribution measurements. The effects of the mass ratio of catalyst to oil, the molar ratio of methanol to oil, and the reaction temperature were studied to optimize the reaction conditions. The experimental results showed that the optimum conditions are a 12:1 molar ratio of methanol to oil, the addition of 3% Ca(OCH 2 CH 3 ) 2 catalyst, and a 65 °C reaction temperature. A 95.0% biodiesel yield was obtained within 1.5 h in these conditions, and the activation energy was 54 149 J/mol. It also indicated that the catalysis performance of calcium ethoxide is better than that of CaO. Besides, a 91.8% biodiesel yield was obtained when it catalyzed soybean oil to biodiesel with ethanol.

Magnesium borate hydroxide (MgBO2(OH)) nanowhiskers with a diameter of 20–50 nm and a length of 0.5–3 μm were synthesized via a facile hydrothermal route, using MgCl2·6H2O, H3BO3, and NaOH as the reactants. Mg7B4O13·7H2O with poor crystallinity was formed after coprecipitation of the reactant solutions at room temperature, the hydrothermal treatment of the slurry at 240 °C for 18 h led to the formation of uniform MgBO2(OH) nanowhiskers with high crystallinity and preferential growth direction along the (200) plane.

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A flux-assisted thermal conversion route to the pore-free high crystallinity magnesium borate (Mg 2 B 2 O 5 ) nanowhiskers with a length of 0.47-3.0 µm, diameter of 50-240 nm, and aspect ratio of 5-36 at a relatively low temperature of 650-700 °C (200-350 °C lower than that needed via the traditional method) was developed in this paper. Magnesium borate hydroxide [MgBO 2 (OH)] nanowhiskers were first prepared by a coprecipitation-hydrothermal approach at 240 °C for 18 h by using MgCl 2 • 6H 2 O, H 3 BO 3 and NaOH (or KOH) as the raw materials and then calcined to produce Mg 2 B 2 O 5 nanowhiskers. The resultant NaCl (or KCl) in the coprecipitation served as the flux and played a key role in the thermal conversion of MgBO 2 (OH) nanowhiskers as the transport medium for the rearrangement of structural units of Mg 2 B 2 O 5 , leading to the final formation of the pore-free Mg 2 B 2 O 5 nanowhiskers with uniform one-dimensional morphology, high crystallinity, and twin crystal structures.

The purpose of this work is to study the feasibility of extraction and recovery of formic acid and acetic acid in the industry synthesis of these two acids. In this work, extraction equilibria of formic and acetic acid with kerosene solutions of such phosphate-containing extractants as trialkylphosphine oxide (TRPO) and tributyl phosphate (TBP) were studied. The solutions of formic and acetic acid in aqueous phase at equilibira ranged from 0.4 mol‚L -1 to 8 mol‚L -1 . The influences of temperature on extraction equilibria were also studied. A model was proposed to describe the equilibria by postulating the structure of the complexes. The parameters in the model were obtained by fitting the experimental data, and the values predicted by this model are very close to the measured results.