• Journal of Korean Society for Atmospheric Environment
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• v.10 no.2
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• pp.83-89
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• 1994

The reaction of sulfur dioxide with cupric oxide was investigated over a temperature range of 300-50$0^{\circ}C$, and the regenaration reaction was studied using cupric sulfate and hydrogen over a temperature range of 240-35$0^{\circ}C$ in a fixed bed reactor. The experimental results showed that the efficiencies for elimination and regenaration reactions were maximum at 45$0^{\circ}C$ and at 30$0^{\circ}C$ respectively. In both cases the experimental data could be interpreted properly by shrinking unreacted core model while the chemical reaction is rate controlling step. The reaction rate constants were determined to be 24.88 exp(-6724/RT) (cm/min) for elimination reaction, and 0.0165 exp(-2047/RT)(cm/min ) for regeneration reaction.

• Journal of Plant Biotechnology
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• v.45 no.1
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• pp.55-62
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• 2018

In the present study in vitro mutagenesis was used to study the effect of gamma irradiation and EMS on callus induction, morphogenesis and production of multiple shoots from different explants of Citrullus colocynthis (L.) Schrad. Gamma radiations (5 kR to 20 kR) and certain chemicals have been effected on plant growth developments and changes of biochemical metabolisms in plants. Murashige and Skoog (MS) medium containing with auxins such as NAA, IAA, 2,4-D (0.5 ~ 2.0 mg/l), cytokinines BAP, kn TDZ, (0.5 ~ 2.5 mg/l), L-Glutamic acid (1 ~ 2 mg/l) and Coconut milk (10 ~ 20%). After 5 weeks on induction media, explants and callus (EC) were exposed to 5 kR, 10 kR, 15 kR and 20kR, of gamma radiation and treated with 1, 2, 3, 4 and 5 mM ethyl methane sulphonate (EMS) for 30 min. The highest percentage of callusing was observed (70%) stem irradiated with 5 kR and significantly decrease in fresh and dry weight of callus in the below 4 kR doses and above 20 kR doses, there was a progressive decrease in the fresh weight and dry weights when compared to control callus. Maximum percentage of plantlet regeneration (59%) was induced from callus exposed to 15 kR gamma irradiation on MS media fortified with 2.0 mg/l 2,4-D + 2.0 mg/l BAP + 2.0 mg/l L-glutamic acid. Increase in gamma irradiation dose above 15 kR and 5 mM EMS reduced regeneration capacity of callus. Doses higher than 20 kR and 7 mM EMS was lethal to micropropagated plants of Citurullus colocynthis.