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Current U.S. Department of Energy strategies for meeting energy crises include efforts to promote the cogeneration of energy. One cogeneration allocation is the energy-saving potential involved in the cogeneration of process heat and electricity. However, cogeneration technologies often face an unfavorable economic climate due to increasingly stringent environmental standards. This paper investigates the policy options which might encourage the adoption of cogeneration technologies and still provide for an adequate level of environmental protection. 相似文献
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Reproduction and growth of the freshwater prawn, Palaemon paucidens (Decapoda: Palaemonidae) in a lake of Korea 总被引:1,自引:0,他引:1
Kim JC Ma CW Oh CW Paik SG 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(2):163-168
This study analyzed the reproduction and growth of freshwater prawn, Palaemon paucidens De Haan 1844 from Suk-dang lake(Korea). The analysis of the sex ratio showed a higher proportion of males than that of females. The average size of the eggs was 6.12 (+/-0.55) mm3 in the non-eyed stage (stageA) and 7.20 (+/-0.86)mm3 in the eyed stage (stage B). The reproductive output (RO) calculated with the dried-body weight of an incubating female and the weight of the eggs in dried condition was 26.97% (n = 17) of the average females weight. Incubating prawn appeared in April, and the gonadosomatic indices(GSI) showed the highest value during three months from January to March. Based on the month when there was a high proportion of incubating females with a high GSI, the estimated spawning season of P. paucidens was April. The maturity of the female was evaluated by the development of the ovaries and the existence of eggs. The average body length when 50% of the females in the group reached maturity was 8.55 (+/-2.74) mm. The analysis of the length-frequency distribution showed that the life span of P. paucidens ranged from 12 to 13 months. Females mature faster than males. 相似文献