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41.
The carbonization of dehydrated johkasou sludge was examined using batch-type equipment. Based on the temperature changes in the carbonization room and the gas combustion room, the carbonization process was divided into three phases: phase I, drying the sludge; phase II, thermal decomposition of the dried sludge; phase III, after phase II. The times required for phases I and II were strongly correlated with the amounts of water and solid matter, respectively, in dehydrated sludge. The reduction rate of the sludge on completion of phase I was about 90% on average, and the decomposition rate of solid matter increased with time during phase II or phase II plus phase III until it reached about 50%. TOC concentration of the eluate from the carbonized sludge was used as an index to evaluate the progress of the carbonization process, and the highest temperature in the carbonization room was recognized as an important operational factor. The specific surface area and pore volume of carbonized sludge were smaller than those of charcoals and activated carbons by 1–3 orders of magnitude and 1–2 orders of magnitude, respectively. No elution of heavy metals was observed from any of the carbonized sludges examined. The reduced amount of carbon in dehydrated johkasou sludge was estimated to be about 25% of the decomposed organic matter.  相似文献   
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Phytoplankton standing crop (chlorophyll a) and primary productivity were recorded, and zooplankton biomass was estimated in the two large bays of Australia, the Great Australian Bight on the south coast (December, 1965) and the Gulf of Carpentaria on the north coast (December, 1968). In the Gulf of Carpentaria, the phytoplankton standing crop (average, 27.3 mg chlorophyll a m-2) and primary productivity (average, 133.1 mg C m-2 h-1), as well as zooplankton biomass (average, 305.3 mg wet weight m-3) are much higher than in the Great Australian Bight (12.1 mg chlorophyll a m-2, 18.2 mg C m-2 h-1, 7.1 mg wet weight m-3, respectively). The unexpectedly low productivity values in the Great Australian Bight are attributable to environmental conditions of this bay, which obtains neither replenishment of nutrients from the land nor receives upwelling of deep water.  相似文献   
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Atmospheric concentrations of 4-oxopentanal (4-OPA) in both gas and particulate phase were measured at the experimental forest, 200 km north of Sapporo, Japan, from August 13 to 15, 2001. 4-OPA was collected using an annular denuder sampling system and measured with a gas chromatography employing benzylhydroxyl oxime derivatization. Its gas phase concentrations ranged from 180 ng m(-3) (44 pptv) to 1570 ng m(-3) (384 pptv), whereas those in the particulate phase were from below the detection limit (25 ng m(-3)) to 207 ng m(-3). The particulate 4-OPA accounted for 28% (particle/(gas+particle)) of the total concentration as the maximum at 06:00 on August 15th (average: 10%). The particulate concentrations of 4-OPA were found to be comparable to those of pinonic acid, indicating that 4-OPA is also an important constituent of organic aerosols in the forestal atmosphere. Here, we report, for the first time, the concentrations of 4-OPA in both gas and particulate phase and its diurnal variations in the forestal atmosphere.  相似文献   
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Myxomycetes are organisms characterized by a life cycle that includes a fruiting body stage. Myxomycete fruiting bodies contain spores, and wind dispersal of the spores is considered important for this organism to colonize new areas. In this study, the presence of airborne myxomycetes and the temporal changes in the myxomycete composition of atmospheric particles (aerosols) were investigated with a polymerase chain reaction (PCR)-based method for Didymiaceae and Physaraceae. Twenty-one aerosol samples were collected on the roof of a three-story building located in Sapporo, Hokkaido Island, northern Japan. PCR analysis of DNA extracts from the aerosol samples indicated the presence of airborne myxomycetes in all the samples, except for the one collected during the snowfall season. Denaturing gradient gel electrophoresis (DGGE) analysis of the PCR products showed seasonally varying banding patterns. The detected DGGE bands were subjected to sequence analyses, and four out of nine obtained sequences were identical to those of fruiting body samples collected in Hokkaido Island. It appears that the difference in the fruiting period of each species was correlated with the seasonal changes in the myxomycete composition of the aerosols. Molecular evidence shows that newly formed spores are released and dispersed in the air, suggesting that wind-driven dispersal of spores is an important process in the life history of myxomycetes. This study is the first to detect airborne myxomycetes with the use of molecular ecological analyses and to characterize their seasonal distribution.  相似文献   
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The major sources of dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs)) in the environment in Japan have been considered to be combustion by-products, pentachlorophenol (PCP) formulations, chlornitrofen (CNP, 4-nitrophenyl-2,4,6-trichlorophenyl ether) formulations, and PCB products. Data on PCDDs, PCDFs and DL-PCBs from the four sources were analyzed, and indicative congeners whose concentrations were highly correlated with WHO-2006 toxic equivalencies (TEQs) were identified for each source sample. The indicative congeners for combustion by-products, PCP formulations, and CNP formulations were 2,3,4,7,8-pentachlorodibenzofuran, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, and 1,2,3,7,8-pentachlorodibenzo-p-dioxin, respectively; for PCB products, the indicative congeners were IUPAC Nos. #126- and #105-pentachlorobiphenyls. Moreover, using the data on PCDDs, PCDFs and DL-PCBs, we developed a set of equations for estimating the apportionment of TEQs from the four sources by using only the concentrations of the above-mentioned five indicative congeners. The equations were used along with the analysis results of different types of environmental samples collected from Japan, to determine the TEQ contributions of the four sources. The obtained values of TEQ contributions seemed to be reasonable. The estimation method was developed by using the data on major dioxin sources in Japan, and therefore, it is generally adaptable to environmental samples from any part of Japan. The method may be usable for regions outside Japan if source identification is carried out and the estimation equations are modified appropriately.  相似文献   
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Based on a study of an experimental wild plant certification project implemented within a tribal community in India, this paper explores how wild plant collectors respond to two contradictory objectives of certification, namely, conserving a targeted plant species while promoting its sale. By providing economic incentives through certification, the project aimed to induce a shift from the collection of immature berries to mature berries from a targeted tree species. However, the majority of the collectors increased their harvests of mature berries while continuing to collect the same quantities of immature berries. This unanticipated project outcome can be attributed to the unique nature of wild plants as an uncertain income source that requires no investment. Evidently, collectors have developed their own concepts of ecological and economic sustainability derived from this unique income source endowed by nature, and have incorporated the new economic opportunity into their own natural resource management strategies.  相似文献   
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Since the discovery in 1985 of hypervariable minisatellite regions in human DNA, DNA fingerprinting has been widely used in animals and plants. Although many different probes have been developed recently, most investigators still use 33.15 and 33.6 human polycore minisatellites for hybridization studies of cetaceans. This animal order shows considerably less variability than humans, and thus some limitations have to be taken into account when using these probes. The present study demonstrates that the short repetitive tandem oligonucleotide (GGAT)4 hybridizes with cetacean (Globicephala macrorhynchus andGrampus griseus) DNA, yielding individual-specific patterns of bands or DNA fingerprints. Freedom of design and shorter hybridization times of oligonucleotides allow an increase in the number of usable probes used, helping to overcome some of the problems found when only human polycore minisatellites are used.  相似文献   
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