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Chatuchak, Thailand

Dararutana P.,Phaholyothin Road | Won-in K.,Kasetsart University | Sirikulrat N.,Chiang Mai University
Chiang Mai Journal of Science

In ancient time, yellow colored glass which used for luxury art glass was actually silver nanotechnology at work by the addition of silver compound into the molten glass. In this work, the lead-alkali silica glass which fabricated using local quartz sands as the silica raw material was added with various concentrations of silver nitrate. Scanning electron microscope coupled with energy dispersive X-ray spectroscopy (SEM-EDS) was used to characterize their morphology. Physical and optical properties such as density, refractive index and optical absorption were also measured. After the complete conventional melting process, the bubblefree yellowish glasses were yielded. SEM micrographs showed the presence of silver nanoparticles in the glass matrix that confirmed by EDS. The refractive indices and densities were increased as the increase of the silver contents. It was also showed that the more brilliance on the surface of the glass products was obtained after fired. Source

Poomipan P.,Kasetsart University | Suwanarit A.,Kasetsart University | Suwanarit P.,Kasetsart University | Nopamornbodi O.,Phaholyothin Road | Dell B.,Murdoch University
Journal of Plant Nutrition and Soil Science

Maize (Zea mays L.) is an important crop in central Thailand where fallow is widely practiced and farmers are interested in crop rotation and beneficial soil biota. A pot experiment using a Typic Paleustult (topsoil + subsoil) from the National Corn and Sorghum Research Centre, Nakhonratchasima Province, Thailand was undertaken over three successive crops to evaluate effects of agronomic practices on populations of arbuscular mycorrhizal (AM) fungi and to determine whether reintroduction of a local Glomus was beneficial to maintain maize yield. The three crops and their treatments were: (1) preceding crop: maize grown in all pots; (2) subexperiment 1: agronomic practices [maize, fallow ± soil disturbance, fallow with solarization, non-AM host (cabbage)]; and (3) subexperiment 2: maize ± Glomus sp. 3 at three rates of P fertilization (0, 33, 92kg P ha-1). The AM-fungal community was established under the preceding crop. In subexperiment 1, the three fallow treatments decreased (30%-40%) the total AM spore number in the topsoil whereas there was no change under maize or cabbage. Glomus, the dominant genus, showed sensitivity to fallow. In subexperiment 2, inoculation with Glomus sp. 3 enhanced total AM spore number and root colonization when applied following the three fallow treatments. Furthermore, inoculation promoted grain yield; at nil P following fallow ± soil disturbance, at 33kg P ha-1 following fallow without soil disturbance, and following solarization. Two treatments, maize following maize and maize following cabbage, did not respond to inoculation with Glomus sp. 3. Overall, the results suggest that reintroduction of Glomus sp. 3, a local AM fungus in this soil, may overcome negative effects of fallow and promote effectiveness of P fertilizer. Further work is needed to evaluate the benefits of other indigenous AM species that persist under modern fertilization practices. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Won-In K.,Kasetsart University | Sirikulrat N.,Chiang Mai University | Dararutana P.,Phaholyothin Road
Advanced Materials Research

Lead glass that shows a high refractive index is the best known and most popular for radiation shielding glass. Due to the toxic of lead compounds on the human organisms as well as the environmental issues, lead free glass was fabricated by using some heavy elements such as barium and bismuth to replace lead. In this study, colorless lead free glass samples were prepared from 40 wt% local quartz sand and various concentration of BaCO3 (20-40 wt%) as the main compositions in order to study radiation shielding property. The glass mixtures were melted conventionally using electric furnace at the maximum temperature of 1250°C with 4 hr dwelling time. The gamma attenuation characteristics were studied for the photon energy of 662 keV from Cs-137. Density and refractive index were also determined. It was found that a variation of prepared glass samples can be produced both in terms of clarity and radiation shielding properties. The attenuation coefficients were linearly increased as the increase of BaCO3 content. The density and refractive index were also increased. The linear and mass attenuation coefficients of the glass sample containing 40 wt% BaCO3 were 0.234 cm-1 and 0.0726 cm2g-1. In conclusion, a low density glass samples will give rise less attenuation than a high density ones. It can be concluded that the lead-free high refractive index glass that is one of the environmental materials can be used as the gamma radiation shielding glass. © (2011) Trans Tech Publications. Source

Won-In K.,Kasetsart University | Dararutana P.,Phaholyothin Road
Advanced Materials Research

The effect of varying the TiO2-content on the lead-free high refractive index glass based on 25 wt% barium carbonate added in replacing lead oxide was prepared and its physical, optical, and electrical properties were investigated. Seven glass samples were synthesized and characterized by using an analytical balance, a refractometer, a LCR meter and an X-ray diffractometer. Specific gravity, refractive index, and dielectric constant increased linearly as the increasing of the TiO2-content. The amorphous state of modification of glass structure due to TiO2 addition was confirmed. © (2011) Trans Tech Publications. Source

Arirob W.,Kasetsart University | Insung A.,King Mongkuts University of Technology Thonburi | Pumnuan J.,King Mongkuts University of Technology Thonburi | Won-In K.,Kasetsart University | Dararutana P.,Phaholyothin Road
Advanced Science Letters

Different concentrations of tannin crude extract from cassava leaves were used for direct spraying, dipping, choice and no-choice repellent test for controlling cassava mealy bug (Pseudococcus jackbeardsleyi Gimpel and Miller). By direct spray method, it was showed that tannin crude extract could not kill cassava mealy bug as insecticide but remarkably repelled mealy bug. Dipping method at 1,500 mg/l tannin concentration could only kill the mealy bug of 7.4% and seemed to decrease plant damage of 32.52% when compared with control. Field experiment revealed that spraying with 1,000 mg/l tannin extract concentration could keep cassava clean, less damaging of mealy bug as well as cassava could promote new apical bud, axially growth and straight trunk. It was wondering that extract from cassava leaves could be used as cassava mealy bug repellant. © 2013 American Scientific Publishers. Source

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