Tomohisa Yoshioka

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Cathode ray tube funnel glass is an environmentally problematic relict of old television sets. In particular, landfilling of this material is strongly discouraged because of its high lead content. However, recovery of this toxic lead could prevent its release into the environment and allow its reuse. In this research, lead was separated from the glass(More)
Hybrid organically bridged silica membranes have attracted considerable attention because of their high performances in a variety of applications. Development of robust reverse osmosis (RO) membranes to withstand aggressive operating conditions is still a major challenge. Here, a new type of microporous organosilica membrane has been developed and applied(More)
Pd-silica mixed-matrix membranes with superior H(2) permeability and hydrothermal stability at high temperatures were successfully fabricated using a sol-gel method. The Pd-silica layer was quite thin (100-200 nm) and small Pd particles (several nm) dispersed well in an amorphous silica matrix.
Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully(More)
A sol-gel method was applied for the development of highly permeable hydrogen separation membranes using bis(triethoxysilyl)ethane (BTESE) as a silica precursor. Hybrid silica membranes showed quite high hydrogen permeance (1 x 10(-5) mol m(-2) s(-1) Pa(-1)) with a high H(2)-to-SF(6) selectivity of 1000 because of loose organic-inorganic silica networks.(More)
Nanoporous titania membranes with controlled pore sizes ranging from 0.7 to 2.5 nm, which had molecular weight cutoffs (MWCO) ranging from 500 to 2000, were successfully prepared by sol-gel processing, and the transport characteristics were evaluated across a temperature range of 30-80 degrees C. With increasing temperature, the permeate flux increased 2-(More)
The mechanisms involved in pressure driven gas permeation through a micropore on vitreous SiO2 membranes were examined molecular dynamics (MD) simulation. Virtual amorphous SiO2 membranes were prepared by the melt-quench method utilizing modified Born-Mayer-Huggins (BMH) pair potential and Stillinger-Weber (SW) three-body interactions. A dual control plane(More)
A new concept was proposed to control the pore size in a novel silica membrane. The tuning of the pore sizes in triethoxysilane (TRIES)-derived membranes was successfully conducted via an in situ reaction between NH3 and Si-H groups at high temperatures. The formation of Si-NH2 and/or Si-NH groups in the silica structure enhanced the hydrogen selectivity.
A new molecular dynamics simulation method was successfully applied to construct a homogeneous organic-inorganic hybrid silica membrane using the hybrid-pcff (h-pcff) potential function. Analysis suggested that the hybrid BTESE silica membrane provided a looser network and larger cavity size for the enhancement of gas permeability and selectivity.
Amorphous SiO(2) membranes were prepared via a 2-step plasma-enhanced CVD (PECVD) technique at room temperature on porous TiO(2)/Al(2)O(3) substrates. SiO(2) membranes showed molecular sieving properties with a high separation factor for He/N(2) and He/H(2), and high thermal stability, indicating the successful preparation of high-performance membranes at(More)