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41.
FunctionofBasicFireResearchToshisukeHiranoDepartmentofChemicalSystemEnginering,TheUniversityofTokyoABSTRACTSometimes,unreason...  相似文献   
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To reveal the mechanism underlying intrapopulation variation in the use of feeding habitats (oceanic vs. neritic) by adult female loggerhead turtles (Caretta caretta), we compared telomere length in the epidermis (a proxy for age) between oceanic- and neritic-foraging recruits (first-time nesters). Based on egg-yolk stable isotope ratios, recruits at Yakushima Island, Japan, were clearly divided into small oceanic planktivores and large neritic benthivores. There were no significant differences in telomere length between oceanic and neritic foragers, suggesting that they start reproduction at similar ages. Turtles that experienced faster growing conditions during their oceanic early lives may achieve sexual maturity there, while others may move from oceanic areas into neritic habitats, switching diets from nutrient-poor macroplankton to nutrient-rich benthic fauna in order to compensate for their earlier slow growth rate and continue their sexual development, reaching maturity in neritic waters.  相似文献   
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Chitin biodegradation and wounded bark tissue healing were demonstrated in several evergreen and deciduous trees by dressing with a sheet of chitin-containing films or sponges. Chitinase activities in the tree bark tissues around the wounds were enhanced by this treatment up to four times those of the untreated wounds. Significant seasonal changes of chitinase activities were observed with the bark and leaf tissues of deciduous trees, but few with those of evergreen trees. A sheet of chitin films implanted or dressed in the tree bark tissues was biodegraded within 4 to 24 weeks after implantation and was assimilated into the wounded bark tissues, resulting in the stimulation of the wounded bark tissue healing.  相似文献   
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Structure of flames propagating through aluminum particles clouds and combustion processes of the particles have been examined experimentally to understand the fundamental behavior of a metal dust explosion. The combustion process of individual aluminum particles in a flame propagating through the aluminum particles cloud has been recorded by using a high-speed video camera with a microscopic optical system, and analyzed. The flame is shown to be consisted of a preheat zone of about 3 mm thick, followed by a combustion zone of 5–7 mm thick. In the combustion zone, discrete gas phase flames are observed around each aluminum particle. Also an asymmetric flame around a particle is observed, which might be caused by an ejection of aluminum vapor from a crack of oxide shell surrounding the particle.  相似文献   
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The spawning area of the common Japanese conger, Conger myriaster, had remained unknown because spawning adults or its newly hatched larvae were never collected. Using genetic identification, we determined that C. myriaster spawns far offshore in the western North Pacific, just west of the spawning area of the Japanese eel, Anguilla japonica. In June 2008, six newly hatched C. myriaster larvae, 5.6–6.9 mm, were collected at the eastern edge of where many small unidentified Conger leptocephali (7–20 mm) were collected previously. The offshore spawning location of C. myriaster is analogous to that of the American conger eel, Conger oceanicus, and the American eel, Anguilla rostrata, in the Sargasso Sea, suggesting that convergent evolution of large-scale reproductive migration strategies in both anguillid and conger eels has occurred in the north Atlantic and Pacific subtropical gyres. The realization that two anguillids, A. rostrata and A. japonica, and two congers, C. oceanicus and C. myriaster, have evolved almost identical migration strategies in widely separated ocean basins suggests that natural selection for larval survival and recruitment success has resulted in long offshore spawning migrations in two phylogenetically distant taxa of anguilliform eels.  相似文献   
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Research on leachate recirculation from different types of landfills   总被引:5,自引:0,他引:5  
Landfills can produce a great amount of leachate containing highly concentrated organic matter. This is especially true for the initial leachate from landfilled municipal solid wastes (MSW) that generally has concentrations of COD(Cr) and BOD(5) up to 80,000 and 50,000mg/L, respectively. The leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelerates organic decomposition through water saturation control. Data from experimental results indicated that leachate recirculating could reduce the organic concentration considerably, with a maximum reduction rate of COD(Cr) over 95%; and, using a semi-aerobic process, NH(3)-N concentration of treated leachate could be under 10mg/L. In addition, the organic concentration in MSW decreased greatly.  相似文献   
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This article analyses elemental composition of suspended particulate matter (SPM) samples collected monthly from 1999 to 2005 at two locations in Yokohama, Japan. Microwave digestion and inductively coupled plasma mass spectroscopy was employed to measure Mg, Al, Ca, V, Cr, Mn, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Pb, and Bi. Water-soluble ions (Na?+?, NH4 ?+?, K?+?, Ca2?+?, Cl???, NO3 ???, and SO4 2???) and carbonaceous mass (elemental and organic carbon) were detected using ion chromatograph and CHN analyzer, respectively. The results indicate that the composition of SPM on one of the sites is determined by automobile emissions and on the other by industrial combustions. The impact of the emission regulations for automobiles in large Japanese cities, which were enacted during 2002 and 2003, on the SPM composition of the samples is also studied.  相似文献   
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It is very important that waste should be controlled and appropriately handled in a waste disposal stream, considering its impact on the environment. In this research, the LCA-EA model was applied to the current waste disposal stream of the BMR as well as other waste disposal stream scenarios, so that treatment cost, environmental load and environmental cost were assessed quantatively. The results of this study showed that in the current waste diposal stream in Bangkok, there were large contributions from carbon dioxide and methane to the greenhouse gas emissions from the stream. The study was able to quantify the reductions in environmental load associated with various waste disposal stream scenarios, using the baseline scenario as a standard.  相似文献   
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