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Efficient protocols for in vitro shoot growth and ex vitro root formation from in vitro-derived shoots under light-emitting diodes (LEDs) with simple ventilation were developed for rabbiteye blueberry cv. ‘Titan’. Red LEDs promoted shoot elongation while blue LEDs induced short shoots with enhanced accumulation of leaf chlorophyll contents. A combined treatment of 80% red with 20% blue LEDs was found the most suitable for plant growth, and more effective than 50% red mixed with 50% blue LEDs or fluorescent lamps as the control treatment. The use of ventilated vessels with ambient CO2 enrichment from a growth chamber resulted in healthy plants having greatly improved shoot length, leaf expansion, leaf chlorophyll contents and dry weight of both shoots and roots. In vitro-cultured shoots could be directly rooted at 100% under non-sterile conditions using a perlite-peat mixture with careful controls of high humidity. These results suggest that LEDs, particularly when coupled with ventilated vessels, should be used as a primary light source for replacing conventional fluorescent tubes in large-scale production of rabbiteye blueberries.

Light-emitting diodes (LEDs) are useful for the growth of many plants, but not known for blueberry species. This study examined the effects of fluorescent lamps and 100 % red, 80 % red plus 20 % blue, 50 % red plus 50 % blue, and 100 % blue LEDs on the growth and development of highbush blueberry shoots under aseptic and non-aseptic conditions. Results revealed that monochromatic blue LEDs accumulated the highest contents of leaf chlorophylls. In contrast, monochromatic red LEDs inhibited chlorophyll accumulation, but produced the longest shoots and roots and provided high percentages of side shoot formation from ex vitro plants. Mixed LEDs, particularly 50 % red plus 50 % blue light, improved plant growth with respect to notably increased shoot and root biomass. Direct rooting of in vitro shoots under non-aseptic conditions was readily achieved using a commercial mixture of perlite and peat moss with high humidity controls. These findings obviously suggest the efficient use of LEDs to replace traditional fluorescent lamps in large-scale propagation of the highbush blueberry, and also pave the way for future studies on LEDs for standardizing micropropagation protocols to shrub crops and woody plants.

Conformation selective: A new technique of ultraviolet-ultraviolet hole burning spectroscopy that can be applied to ions stored in a quadrupole ion trap (QIT) is developed and used to obtain the conformation-selective electronic spectra of dibenzo[18]crown-6 complexes with alkali metal cations (M(+), see picture; F(+) = fragment).

The effects of alkaline hydrolysis on the chemical structure of polyacrylonitrile (PAN) hollow fiber ultrafiltration (UF) membrane were studied using solid-state 13 C NMR spectroscopy. The PAN membrane was hydrolyzed in an NaOH solution of pH 13, which is generally used in water industry for anti-fouling treatments of UF membranes but is much weaker than the alkaline concentrations (0.5–2.5 N) used so far in conventional 13 C NMR studies. All of the carbon sites of the PAN were characterized by the solid-state 1 H– 13 C CPMAS and HETCOR NMR spectra. Upon the alkaline treatments, the chemical conversion from the cyano functional groups of the PAN to the carboxylates was observed. The analysis of the 13 C CPMAS NMR spectra obtained as a function of the treatment time for 4–96 h showed that the chemical modification occurred very rapidly in the early stage (≤6 h) of the reaction but then proceeded slowly up to 96 h. The relative amount of the hydrolyzed acrylonitrile units after 96 h of the reaction at room temperature was estimated to be only 3.8%. We suggested that the alkaline hydrolysis of the PAN membrane proceeds at two distinct rates, a rapid conversion of the cyano groups on or near the membrane surface and a slow conversion of the bulk.

Mechanical and thermal properties of Si3N4 ceramics with various rare-earth oxides (La2O3, CeO2, Lu2O3, Dy2O3, Sm2O3, Nd2O3, Yb2O3, and RuO2) were investigated. Flexural strength of silicon nitride with addition of 5vol% Nd2O3, CeO2, Dy2O3, and Sm2O3 showed higher value than that of silicon nitride with Lu2O3 and La2O3 added because they form denser microstructure and smaller elongated grain. Thermal conductivity of silicon nitride with an addition of 5vol% RuO2 was more enhanced than that of silicon nitride added with Nd2O3, Sm2O3, and Dy2O3 because the addition of RuO2 depressed grain growth. It is also associated with lattice oxygen governing thermal conductivity of Si3N4 when added rare-earth oxides.

Iron catalysts promoted with potassium and supported on ion exchanged (H, K) zeolite-Y were examined for catalytic activity and product selectivity in the CO2 hydrogenation. The catalysts were prepared by impregnating the support with iron nitrate followed by calcination and in-situ reduction in hydrogen and were characterized by XRD, AAS, BET, CO2 & H2 Chemisorption, and Temperature Programmed Reduction Technique. The catalytic tests on CO2 conversion were performed at 10 atm and at 573K in a continuous flow system using a fixed bed reactor. It was found that iron oxide was highly dispersed on the zeolites and potassium exchanged zeolite-Y increased the basicity of the catalyst surface. This significantly improved the hydrocarbon yield and the C2 - C4 olefins selectivity. On the other hand, hydrogen exchanged zeolte-Y depressed surface basicity and hence resulted in an increased amount of methane production. Therefore, an attempt has been made to correlate the CO2 hydrogenation activity with the surface properties of the catalysts.