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51.
The present study determined concentrations and patterns of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in specimens of open sea, and Japanese coastal and inland avian species, which have been stored in the Environmental Specimen Bank of Ehime University (es-Bank), to examine the spatial trends. PBDEs and PCBs were detected in all the muscle samples analyzed, suggesting that PBDE pollution has spread even to the remote open sea areas, as in the case of PCBs. Japanese coastal and inland birds accumulated higher concentrations of PBDEs than open sea birds. In addition, higher PBDE/PCB concentration ratios were observed in Japanese coastal and inland birds than in open sea birds, indicating the input of PBDEs into the Japanese terrestrial environment. Compositions of PBDEs varied among avian species with a predominance of BDE47 or BDE153. This could be due to differences in their habitat, food habit and/or biotransformation capacity of PBDEs.  相似文献   
52.
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in a sediment core and in samples of surface sediment and paddy soil collected from the Toyano lagoon and Kameda basin in Niigata, Japan, were analyzed to elucidate the temporal trends of their concentrations in the lagoon sediment and the relationship between the sediment and the paddy soil. The mass balance of these pollutants was also estimated to determine their long-term fate in surface waters. An analysis by chemical mass balance identified the agrochemicals pentachlorophenol and 2,4,6-trichlorophenyl 4-nitrophenyl ether as the major sources of PCDD/Fs. On the basis of the findings regarding the mass balance in the Kameda basin over the last 40 years, we estimate that more than half the input of PCDD/Fs to the Kameda basin has disappeared. We suggest that the PCDD/Fs that flowed out from the paddy fields have been transferred to the lower basin.  相似文献   
53.
Butyltin compounds (BTs) including tributyltin (TBT) and its degradation products, di- (DBT) and mono-butyltin (MBT), were determined in bivalves such as blue mussels (Mytilus edulis) and arkshells (Scapharca broughtonii) collected from Korean coastal waters. BTs were detected in all the blue mussels and arkshells analyzed. The concentrations of total butyltin (sigmaBTs: MBT + DBT + TBT) in blue mussels and arkshells ranged from 49 to 2500 ng/g and 29 to 87 ng/g wet weight, respectively. Higher concentrations of BTs were found in blue mussels collected from Okpo and Kohyonsong Bays and Jangsengpo Harbor where large shipyards and harbors are located with dry-dock facilities. This suggested that maritime activities nearby the harbors play a major role as the source of BTs. Concentrations of TBT in mussels collected from Korea were one of the highest values reported, suggesting ongoing TBT contamination in Korea. Among BTs, TBT was the predominant compound both in blue mussels and arkshells collected from almost all the sampling locations, indicating the fresh input of TBT in Korean coastal waters. Smaller mussels tended to accumulate BTs at higher concentrations than larger ones, which may be due to higher filtration rate of small mussels and/or contact with surface microlayer in intertidal zones.  相似文献   
54.
BACKGROUND: Against increasing environmental adverse effects on human health such as those associated with water and ground pollution, as well as out- and indoor air conditions, trials were conducted to support and promote human health by improving the indoor air atmosphere. This study was performed to estimate the effect of negatively-charged air conditions on human biological markers related to the psycho-neuro-endocrino-immune (PNEI) network. OBJECTIVES: After construction of negatively-charged experimental rooms (NCRs), healthy volunteers were admitted to these rooms and control rooms (CTRs) and various biological responses were analyzed. METHODS: NCRs were constructed using a fine charcoal coating and applying an electric voltage (72 V) between the backside of walls and the ground. Various biological markers were monitored that related to general conditions, autonomic nervous systems, stress markers, immunological parameters and blood flow. RESULTS: Regarding the indoor environment, only negatively-charged air resulted in the difference between the CTR and NCR groups. The well-controlled experimental model-room to examine the biological effects of negatively-charged air was therefore established. Among the various parameters, IL-2, IL-4, the mean RR interval of the heart rate, and blood viscosity differed significantly between the CTR and NCR groups. In addition, the following formula was used to detect NCR-biological responses: Biological Response Value (BRV)=0.498+0.0005 [salivary cortisol]+0.072 [IL-2]+0.003 [HRM-SD]-0.013 [blood viscosity]-0.009 [blood sugar]+0.017 [pulse rate]. CONCLUSIONS: Negatively-charged air conditions activated the immune system slightly, smoothened blood flow and stabilized the autonomic nervous system. Although this is the first report to analyze negatively-charged air conditions on human biological responses, the long-term effects should be analyzed for the general use of these artificial atmospheres.  相似文献   
55.
The stream goby Rhinogobius sp. DA (dark color type) shows exclusive paternal care of the eggs. Males court females in the stream current and previous field observations suggest that females favor males that perform their courtship display in faster water currents, and that such males may have high parental ability because of good physical condition. To validate these observations we examined female choice under controlled laboratory conditions. Mate choice experiments indicated clearly that females preferred males that courted in the faster currents, whereas neither sexually different morphological traits, such as body size, nor the water current alone were important. The experiments with food supply treatments indicated that only males of high physical condition are able to court in the fast currents. Furthermore, males that courted in the fast currents achieved good egg survival, whereas males that were unable to court in the currents did not, due to cannibalism of their egg clutch. Thus, the maximum speed of the water current in which a male courts should be indicative of his quality and of the subsequent survival of eggs under his care. We conclude that Rhinogobius sp. DA females utilize the male courtship display in the water current as an honest indicator of parental quality.Communicated by K. LindströmAn erratum to this article can be found at  相似文献   
56.
A distinctive chlorophyll maximum was detected around 60-m depth in the western North Pacific Ocean and the South China Sea, and almost 55% of the total chlorophyll in the entire water column was found within 50 m around the subsurface chlorophyll maximum (SCM) layer. More than 70% of the chlorophyll was contained in picoplankton which passed through a 3-m Nuclepore but retained on 0.22-m Millipore filters at the SCM as well as the surface layers. By transmission electron microscopic observations, the picoplankton were identified as aChlorella-like coccoid green alga having a section size of 1.2 to 1.5 m and cyanobacteria of 0.5 to 2 m. No obvious difference in these two dominant groups was observed in the SCM and the surface samples except in numerous and heavily stacked thylakoids in the former samples.  相似文献   
57.
Hydrometallurgical recovery of zinc from ashes of automobile tire wastes   总被引:2,自引:0,他引:2  
Study has been performed on the investigation of metal leaching behavior for fly and bottom ashes from automobile tire wastes using acid and alkaline solutions from both viewpoints of environmental protection and resource utilization. The two ashes were found to contain substantial amounts of zinc and iron along with small quantities of cobalt, manganese, magnesium, copper, titanium and aluminum. The fly ash contained a much larger amount of zinc than the bottom ash, and seems to be a promising secondary source for the metal. Effects of such experimental parameters as temperature, time and solid-liquid ratio on the leaching behavior were investigated. Using three mineral acids and citric acid, selective leaching of zinc was successfully attained; the concentration of zinc in the leach liquors from the fly ash reached as high as 20 g l(-1) while the iron leaching was much suppressed. Selective separation of zinc was also attained in the leaching with alkaline solutions, though the percent leaching was lower than that in the acid leaching. Moreover, solvent extraction and precipitation were applied to the metal-loaded leach liquors as downstream processing to evaluate the feasibility of zinc recovery.  相似文献   
58.
Butyltin compounds (BTs) including mono- (MBT), di- (DBT), tri-butyltin (TBT) and total tin (sigmaSn), were determined in the liver of skipjack tuna (Katsuwonus pelamis) collected from Asian offshore waters (off-Japan, the Japan Sea, off-Taiwan, the East China Sea, the South China Sea, off-Philippines, off-Indonesia, the Bay of Bengal), off-Seychelles, off-Brazil and open seas (the North Pacific). BTs were detected in all the skipjack tuna collected, suggesting widespread contamination of BTs even in offshore waters and open seas on a global scale. Considering specific accumulation, Sex-, body length- differences and migration of skipjack tuna did not seem to affect BT concentrations, indicating rapid reflection of the pollution levels in seawater where and when they were collected. Skipjack tuna is a suitable bioindicator for monitoring the global distribution of BTs in offshore waters and open seas. High concentrations of BTs were observed in skipjack tuna from offshore waters around Japan, a highly developed and industrialized region (up to 400 ng/g wet weight). Moreover skipjack tuna collected from offshore waters around Asian developing countries also revealed the levels comparable to those in Japan (up to 270 ng/g wet weight) which may be due to the recent improvement in economic status in Asian developing countries. High percentages (almost 90%) of BTs in total tin (sigmaSn: sum of inorganic tin+organic tin) were found in the liver of skipjack tuna from offshore waters around Asian developing countries. This finding suggests that the anthropogenic BTs represent the major source of Sn accumulation in skipjack tuna from these regions.  相似文献   
59.
We proposed the carbon sink project called “Carbon Sequestration by Forestation and Carbonization (CFC),” which involves biomass utilization and land conservation by incorporating the products of biomass carbonization into the agents for soil improvement, water purification, etc. Our purpose was to demonstrate the potential of the CFC scheme for carbon sequestration, particularly carbon storage in soil. Case studies were conducted in both developing and developed countries. 1. In southern Sumatra, Indonesia, 88,369 Mg-C year−1 of wood residue from a plantation forest and excess bark from a pulp mill would be converted into 15,571 Mg-C year−1 of the net carbon sink by biochar for soil improvement. The fixed carbon recovery of the system is 21.0%. 2. In a semiarid region in western Australia, the carbonization of wood residue was incorporated with multipurpose projects of a mallee eucalyptus plantation that involved the function of salinity prevention. During the project period of 35 years, the total carbon sink would reach 1,035,450 Mg-C with 14.0% by aboveground biomass, 33.1% by belowground biomass and 52.8% by biochar in soil. 3. In southern Kyushu, Japan, the study was focused on the effective use of surplus heat from a garbage incinerator for carbonizing woody materials. Sawdust of 936.0 Mg-C year−1 would be converted into the net carbon sink of 298.5 Mg-C year−1 by carbonization, with the fixed carbon recovery of the system being 31.9%. Consequently, the CFC project could encourage the creation of a carbon sink in soil. However, we recognize that the quality standard of biochar, the stability of biochar in soil, and the methods for monitoring biochar utilization must be clarified before incorporating biochar carbon into the carbon credit system. Throughout this article (except for diagrams and in citation details) carbonized biomass is, with the authors'agreement, called ‘biochar’ in lieu of the commonly used but misleading word ‘charcoal’ (Editor).  相似文献   
60.
The End-of-life Vehicles Recycling Act went into effect on January 1, 2005, in Japan and requires the proper treatment of airbags, chlorofluorocarbons (CFCs), and automobile shredder residue (ASR). The need for optimal treatment and recycling of ASR, in particular, has been increasing year after year because ASR is regarded as being difficult to treat. Dioxin-related compounds, brominated flame retardants (BFRs), heavy metals, chlorine and organotin compounds are all present in high concentrations in ASR. The authors conducted ASR melting treatment tests using a 10-tons/day-scale direct melting system (DMS), which employs shaft-type gasification and melting technology. The results obtained showed that dioxin-related compounds and BFRs were decomposed by this melting treatment. The high-temperature reducing atmosphere in the melting furnace moved volatile heavy metals such as lead and zinc into the fly ash where they were distributed at a rate of more than 90% of the input amount. This treatment was also found to be effective in the decomposition of organotin, with a rate of decomposition higher than 99.996% of the input amount. Via the recovery of heavy metals concentrated in the fly ash, all the products discharged from this treatment system were utilized effectively for the complete realization of an ASR recycling system that requires no final disposal sites.  相似文献   
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