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211.
Faridullah Irshad M Yamamoto S Honna T Eneji AE 《Waste management (New York, N.Y.)》2009,29(1):265-271
For safe and sustainable management of poultry litter, it is important to evaluate and understand the chemical forms and concentrations of their constituent trace elements during treatment for disposal. This experiment was carried out to compare changes in metal (Cu, Mn, Zn, Pb and Ni) fractions in chicken and duck litter after incineration at temperatures ranging from 200 to 900 degrees C. The metals were stepwise fractionated into exchangeable, adsorbed, organically bound, carbonate precipitated and residual forms by extracting with 0.5M KNO3, de-ionized water, 0.5M NaOH, 0.05M Na2 EDTA and 4M HNO3, respectively. The content of total metal and other elements (i.e., Ca, Mg and K) were was also determined. Results showed an increasing trend in the total concentrations of metals with increasing temperature with higher amounts in chicken litter ash (CLA) than duck litter ash (DLA). Higher temperatures significantly reduced the levels of H2O-soluble Mn, Zn and Ni and enhanced those of Cu and Pb. The metal fractions extracted by EDTA and HNO3 increased directly with increasing temperature while the fraction extracted with KNO3 and NaOH decreased with ashing. For Cu, Mn, Pb and Ni, the amount extracted varied in the order EDTA>HNO3>NaOH>KNO3>H2O, but the absolute amounts differed between CLA and DLA. Peak concentrations of the total metals were achieved at the highest burning temperature. The amount of H2O soluble Ca and Mg decreased and K increased in both CLA and DLA with temperature. Total and exchangeable forms of cations increased with increasing temperature. Total Ca was highest in DLA, whereas total Mg and K were higher in CLA. This study indicated that incinerating poultry litter before soil application may have mixed effects on the vulnerable metal fractions by increasing or decreasing some fractions, depending on poultry type. 相似文献
212.
Kenji Yasuda Ikuko Yoda Katsuya Kawamoto 《Journal of Material Cycles and Waste Management》2009,11(4):328-338
Surrogate measurements should be low in cost and quick to perform. To examine its feasibility, continuous surrogate monitoring
was performed using an organic halogen compound (OHC) analyzer. Surrogates for dioxins (DXNs) from waste incinerators were
examined by changing the operating conditions such as the atomized volume of activated carbon added and the temperature at
the inlet of the dust collector. OHCs were measured along with DXNs in flue gas at the inlet and the outlet of the dust collector
of two waste incinerators over five runs; the fly ash was sampled at the same time. Although the final flue gas concentration
of DXNs at the incineration plants was below the regulation criteria, this does not mean complete reduction of DXNs. In addition,
the de novo synthesis of DXNs inside the dust collectors was studied by analyzing the mass balance for DXNs concentrations
in flue gas and fly ash. Semivolatile chlorinated organic compound concentrations at the outlet of the bag filter were basically
well correlated with DXNs levels at the inlet of the bag filter in the test runs. When advanced flue gas treatment is applied
by using a bag filter and lime/activated carbon adsorbent, DXNs that may be generated during flue gas cooling processes move
to the fly ash, and this amount determines the mass balance of the entire system. It may be useful to monitor surrogate organic
halogens for detecting changes in DXN concentrations of both flue gas and fly ash in incineration plants. 相似文献
213.
Kan-ichiro Matsumura Rover J. Hijmans Yann Chemin Christopher D. Elvidge Kenji Sugimoto Wenbin Wu Yang-won Lee Ryosuke Shibasaki 《Sustainability Science》2009,4(2):301-313
Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable
rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and
economic growth. Global patterns of rice production can be mapped by using various criteria linked to domestic income, population
patterns, and associated satellite brightness data of rice-producing regions. Prosperous regions have more electric lighting,
and there are documented correlations between gross domestic product (GDP) and nighttime light. We chose to examine global
rice production patterns on a geographical basis. For the purposes of this study, each country is considered to be made up
of regions, and rice production is discussed in terms of regional distribution. A region is delineated by its administrative
boundaries; the number of regions where rice is produced is about 13,839. We used gridded spatial population distribution
data overlain by nocturnal light imagery derived from satellite imagery. The resultant relationship revealed a correlation
between regional income (nominal values of GDP were used) and rice production in the world. The following criteria were used
to examine the supply and demand structure of rice. Global rice consumption = “caloric rice consumption per capita per day”
multiplied by “regional population values”. Regional rice yields = “country-based production” divided by “harvested area”
(multiple harvests are taken into account). Regional rice production = “regional harvested areas” multiplied by “rice yield
values”. We compared regional rice consumption and production values according to these methods. Analysis of the data sets
generated a map of rice supply and demand. Inter-regional shipping costs were not accounted for. This map can contribute to
the understanding of food security issues in rice-producing regions and to estimating potential population values in such
regions. 相似文献
214.
Takahiro Ishizaka Susumu Tohno Chang-Jin Ma Atsushi Morikawa Masaki Takaoka Fumitaka Nishiyama Kouhei Yamamoto 《Atmospheric environment (Oxford, England : 1994)》2009,43(16):2550-2560
During the transboundary transport of anthropogenic heavy metals by mineral particles providing reaction sites, the divalent metal salt PbSO4 can be converted to PbCO3 in the presence of water. We carried out laboratory experiments to study the transformation process under various conditions by incorporating test particles comprising CaCO3 of a particulate mineral component, PbSO4, and NaCl. After the immersion of PbSO4 particles in contact with CaCO3 particles in a water droplet, the conversion of PbSO4 into PbCO3 was confirmed by the change in morphology of the original particles to stick or needle form; the percentages of the chemical forms relative to the total Pb were determined by X-ray absorption near edge structure (XANES) analysis. Approximately 60–80% of PbSO4 was converted to PbCO3 after 24 h. A small amount of stick particles was detected when NaCl particles attached to PbSO4/CaCO3 particles were exposed to air with a relative humidity (RH) of 80–90% for 24 h. XANES measurements of the samples revealed that the molar percentage of PbCO3 relative to the total Pb content was 4%.Field experiments were also conducted to determine the chemical forms of the Pb particles during the Kosa (Asian dust storm) event. Samples were collected from two remote sites in Japan and Korea. The mass size distribution of Pb aerosols collected in Japan was bimodal with two peaks in the coarse mode; the enrichment factor of Pb suggested that its source was anthropogenic. Pb L3 edge XANES measurements of both samples indicated that they had similar shapes. These measurements also indicated that the major Pb components for the samples collected in Japan were PbO, PbSO4 PbCl2, and PbCO3, with molar percentages of 44%, 30%, 21%, and 5%, respectively. No significant differences were found between the component ratios of the samples collected in Japan and Korea, suggesting that definite transformation did not occur during the transport of the Kosa particles from Korea to Japan. On the basis of these observations, we postulate that the transformation process either occurred mainly before the particles arrived at Korea or did not take place after the particles left continental Asia. 相似文献
215.
Koichi Haraguchi Akio Koizumi Kayoko Inoue Kouji H. Harada Toshiaki Hitomi Mutsuko Minata Miyako Tanabe Yoshihisa Kato Eri Nishimura Yoshiaki Yamamoto Takao Watanabe Katsunobu Takenaka Shigeki Uehara Hye-Ran Yang Min-Young Kim Chan-Seok Moon Hae-Sook Kim Peiyu Wang Aiping Liu Nguyen Ngoc Hung 《Environment international》2009,35(7):1072-1079
Human breast milk samples collected in 2007–2008 from four countries, Vietnam (Hanoi), China (Beijing), Korea (Seoul) and Japan (Sendai, Kyoto and Takayama), were analyzed for persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane-related compounds (CHLs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Comparing with previous surveys, the present study indicates that the DDTs in breast milk from China and Vietnam had gradually decreased during the last decade, but were still 5–10 times higher than those in other nations. The ratios of p,p′-DDE/p,p′-DDT and o,p′-DDT/p,p′-DDT were higher in Beijing than in the other countries, suggesting that there is less fresh intake of commercial DDT products and a possible exposure to dicofol in China. CHL and PCB levels were relatively higher in mothers from Japan, whereas β-HCH and HCB were more common in Chinese women. In Japan, it is suspected that mothers in the urban/coastal area (Sendai) were more continuously exposed to organochlorine pesticides (OCPs) than mothers in the rural/inland area (Takayama). In addition, OCP levels in primiparae were significantly higher than those in multiparae from Japan and Korea. These indicate that both parity and regional factors are major determinants of the levels of OCPs and PCBs in human milk. On the other hand, higher concentrations of PBDEs were observed in mothers' milk from Korea. The congener was dominated by BDE-47 (43–54%), followed by BDE-153 (23–33%) in all regions except for Beijing where BDE-28 (23%) was relatively abundant. In Japanese breast milk, regional and parity-dependent distributions were not observed for PBDEs. Among PBDE congeners, age-dependency was observed for BDE-153, which was negatively correlated (p < 0.05) to the age of mothers in Kyoto (17 participants were housewives), while it increased with age in Sendai (10 participants were clerks). No such correlation was seen for BDE-47, indicating that BDE-47 was ingested and assimilated via different kinetics or routes from BDE-153 in Japan. 相似文献
216.
Comparison of sludge characteristics and PCR-DGGE based microbial diversity of nanofiltration and microfiltration membrane bioreactors 总被引:1,自引:0,他引:1
The objective of this study was to compare the sludge characteristics and microbial community diversity between the submerged nanofiltration membrane bioreactor (NF MBR) and microfiltration membrane bioreactor (MF MBR) treating the same municipal wastewater. The influence of a higher concentration of organic matter and salt was investigated. The results of water qualities showed that the dissolved organic carbon (DOC), total phosphorus (T-P) and salt concentrations of the supernatant in the NF MBR were three, four and two times as high as those in the MF MBR, respectively. The specific oxygen uptake rate of the NF MBR (2.9+/-0.4 mg O(2)g(-1)MLSSh(-1)) was lower than that of the MF MBR (4.3+/-1.1 mg O(2)g(-1)MLSS h(-1)). Result of extractable extracellular polymeric substances showed that the NF MBR sludge had more protein and less polysaccharide compared to the MF MBR sludge, whereas specific amount of total organic carbon were the same in both MBRs. The median floc diameters of the NF MBR and the MF MBR were 72+/-12 microm and 59+/-12 microm, respectively, which could be attributable to the different polysaccharide concentrations between both MBR mixed liquor. A higher concentration of materials (DOC, T-P and salt) in the bioreactor, determined by the high rejection rate of the NF membrane, did not significantly affect the microbial diversity under similar operation conditions. 相似文献
217.
218.
Kousaku Ohkawa Masanori Yamada Ayako Nishida Norio Nishi Hiroyuki Yamamoto 《Journal of Polymers and the Environment》2000,8(2):59-66
The degradation of two kinds of polyion complex (PIC) fibers, chitosan-gellan (CGF), and poly(L-lysine)-gellan (LGF) fibers, by seven species of soil filamentous fungi has been investigated. All of the pure-line soil filamentous fungi, Aspergillus oryzae, Penicillium caseicolum, P. citrinum, Mucor sp., Rhizopus sp., Curvularia sp., and Cladosporium sp. grew on the two fiber materials. Microscopic observation of the biodegradation processes revealed that P. caseicolum on the CGF and LGF grew, along with the accompanying collapse of the fiber matrices. In the biochemical oxygen-demand (BOD) test, the biodegradation of the LGF by P. caseicolum and Curvularia sp. exceeded 97% carbon dioxide generation and the biodegradation of the CGF by A. oryzae was 59%. These results might offer some clues to the applications of the PIC fibers as environmentally biodegradable materials. 相似文献
219.
The distribution and abundance of Japanese common squid [Todarodes pacificus (Steenstrup, 1880)] paralarvae off southern Kyushu Island near the Kuroshio were examined in relation to water types in the
region. Surveys were conducted in 1996 and 1997 using paired, 70 cm diameter Bongo nets. Temperature–salinity plots from 0,
50 and 100 m depths were used to assign sampling stations to three water types: inshore, mixing and Kuroshio. In total, 4103
T. pacificus paralarvae were collected at 59 of 72 stations. Catch densities at positive stations ranged between 8 and 4282 ind./50 m2 sea surface area. Catches during both years were highest in mixing waters, followed by inshore and Kuroshio waters. Total
catches were highest just north of the oceanographic front at the inshore edge of the Kuroshio and declined with increasing
distance away from the front. Catches of paralarvae ≤1.0 mm mantle length also peaked near the front. In both years, ≥85%
of all paralarvae and ≥69% of those ≤1.0 mm mantle length occurred less than 25 km from the front. We conclude that most spawning
off southwest Kyushu occurs near the frontal zone, where Kuroshio and inshore waters meet.
Received: 18 November 1998 / Accepted: 11 May 1999 相似文献
220.
Akio Kamimura Eisuke Konno Shigehiro Yamamoto Takeru Watanabe Kazuo Yamada Fumiaki Tomonaga 《Journal of Material Cycles and Waste Management》2009,11(1):38-41
To develop a new method for the chemical recycling of plastics, we examined the formation of recycled polymers from the recovered
monomeric materials of solubilized waste fiber-reinforced plastics (FRP) under supercritical alcoholic conditions. Treatment
of waste FRP with supercritical MeOH resulted in the formation of monomeric organic compounds that mainly contained dimethyl
phthalate (DMP) and propylene glycol. The presence of these materials was confirmed by gas chromatography and nuclear magnetic
resonance analyses and they were mixed with new DMP and glycols in various ratios to form unsaturated polyesters. The polymerization
progressed successfully for all mixing ratios of the recovered and new DMP. Hardness tests on these recycled polymers indicated
that the polymer made from a 1:1 mixture of recovered and new dimethyl phthalate had almost the same level of hardness as
the polymers made from new materials. We also examined the formation of recycled FRP by using glass fibers and monomeric materials
recovered through the present depolymerization method.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献