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21.
Sun SJ Zhao JH Liu HJ Liu DW Ma YX Li L Horiguchi H Uno H Iida T Koga M Kiyonari Y Nakamura M Sasaki S Fukatu H Clark GC Kayama F 《Chemosphere》2006,62(11):1879-1888
Very limited information is available on body burdens and environmental levels of dioxins and dioxin-like PCBs (dl-PCBs) in mainland China. In the current studies, human milk samples were collected from 30 breastfeeding mothers in Shijiazhuang city (industrialized) and 11 in the Tanshan countryside (agricultural) of Hebei Province in northern China. An additional 20 samples were obtained from mothers in Tokyo, Japan. PCDDs, PCDFs, and dl-PCBs in human milk were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry. Our results show that arithmetic means for body burdens of PCDDs/Fs and dl-PCBs in Hebei were 3.6 and 1.9 pg TEQ g−1 fat, respectively, which were only about one fourth of the levels in Japan. In addition, no difference was found in the chemical levels except dl-PCBs between the urban and rural areas. Based on the results of an in-person interview of the Chinese mothers using a 59-item questionnaire, freshwater fish consumption was found to correlate with the body burden of dioxins. Principal component analysis of dioxin congeners revealed that the patterns of dioxins in the Hebei urban and rural areas are quite similar; however, they are clearly different from those in Japan. Collectively, our results suggest that the lower body burdens of dioxin in Hebei may be due in part to the relatively slow industrialization and a lower consumption of marine foods. Finally, the results indicate that comprehensive monitoring of dioxins and dl-PCBs in humans as well as in the environment and foods is necessary in China. 相似文献
22.
In order to quantify the sources of chemical pollutants in the leachate from reclaimed wastes, chemical substances in 11 different types of industrial wastes were identified. Their elution behaviors were also investigated. Alkanes (5.3-890 ng g(-1)), benzenes (8.1-110 ng g(-1)), polyaromatic hydrocarbons (PAHs) (3.2-560 ng g(-1)), alcohols, steroids, phenol (7.1 ng g(-1)), ketones, furans (190-210 ng g(-1)), phthalates (8.9-560 ng g(-1)), benzoquinones, dibenzothiophene (190 ng g(-1)), benthiocarb (4.2 ng g(-1)), sulfur, nitrile compounds, amino compounds, amido compounds, pyridines, quinolines (1.8-15 ng g(-1)), isoquinolines, carbazoles, acridines, chlordenes (1.5-1.6 ng g(-1)) and nonachlors (1.1-1.6 ng g(-1)) were detected in 9 types of industrial wastes. The chemical substances detected in waste at the highest concentrations were alkanes, PAHs and phthalates. Water supply sludge, dust and brick garbage contained many kinds of chemical substances. The elution behaviors of specific chemical substances, COD and nutrients varied by characteristic and production process of each waste. Over 100 different compounds were detected in pyrolysis products including carbohydrate, carotynoid, amino acids, proteins, humic acids, lignin and combustion products. 相似文献
23.
Transport and transformation of sulfur compounds over East Asia during the TRACE-P and ACE-Asia campaigns 总被引:4,自引:0,他引:4
Meigen Zhang Itsushi Uno Yasuhiro Yoshida Yongfu Xu Zifa Wang Hajime Akimoto Timothy Bates Trish Quinn Alan Bandy Byron Blomquist 《Atmospheric environment (Oxford, England : 1994)》2004,38(40):6947
On the basis of the recently estimated emission inventory for East Asia with a resolution of 1×1°, the transport and chemical transformation of sulfur compounds over East Asia during the period of 22 February through 4 May 2001 was investigated by using the Models-3 Community Multi-scale Air Quality (CMAQ) modeling system with meteorological fields calculated by the regional atmospheric modeling system (RAMS). For evaluating the model performance simulated concentrations of sulfur dioxide (SO2) and aerosol sulfate (SO42−) were compared with the observations on the ground level at four remote sites in Japan and on board aircraft and vessel during the transport and chemical evolution over the Pacific and Asian Pacific regional aerosol characterization experiment field campaigns, and it was found that the model reproduces many of the important features in the observations, including horizontal and vertical gradients. The SO2 and SO42− concentrations show pronounced variations in time and space, with SO2 and SO42− behaving differently due to the interplay of chemical conversion, removal and transport processes. Analysis of model results shows that emission was the dominant term in regulating the SO2 spatial distribution, while conversion of SO2 to SO42− in the gas phase and the aqueous phase and wet removal were the primary factors that controlled SO42− amounts. The gas phase and the aqueous phase have the same importance in oxidizing SO2, and about 42% sulfur compounds (25% in SO2) emitted in the model domain was transported out, while about 57% (35% by wet removal processes) was deposited in the domain during the study period. 相似文献
24.
Shu Saeki Junya Kano Fumio Saito Kaoru Shimme Seiichi Masuda Tsuyoshi Inoue 《Journal of Material Cycles and Waste Management》2001,3(1):20-23
Polyvinyl chloride (–CH2–CHCl–)
n
(PVC) was ground with a powdered inorganic material (CaO, CaCO3, SiO2, Al2O3, or slag) in a planetary ball mill under atmospheric conditions to investigate the effect of additions on its dechlorination.
The grinding causes a dehydrochlorinating reaction, forming a mixture of partially dechlorinated PVC and inorganic chloride,
depending on the grinding time. The dechlorination increases as the grinding progresses, and is improved with increasing amounts
of additives. The most effective additive is a mixture of CaO, SiO2, and Al2O3, which has the same constituent components as blast furnace slag. CaO, a mixture of CaO, SiO2, and blast furnace slag, are also effective, but CaCO3 is the least effective additive tired.
Received: August 3, 2000 / Accepted: September 21, 2000 相似文献
25.
Seiichi Miyamoto Hinrich L. Bohn 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1051-1054
An equation derived for initial collection of efficiency E0 of a gravel bed filter predicts that — ln(1 — E0) is proportional to the thickness of the gravel layer, to the — 5/3 power of the diameter of uniform gravels, and to the — 2/3 power of the Darcy airflow velocity. The experimental data obtained from NH4CI fume removal from dry air at room temperature by sieved gravel fractions generally supported the equation, except that the effect of mean gravel size was represented by the —1.43 power of the average diameter. 相似文献
26.
Fluxes of carbon dioxide, methane and nitrous oxide in two contrastive fringing zones of coastal lagoon, Lake Nakaumi, Japan 总被引:9,自引:0,他引:9
We measured fluxes of carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) simultaneously in two typical fringing zones, sandy shore and salt marsh, of coastal lagoon, Lake Nakaumi, Japan, in mid-summer 2003. Our aim was to quantify net the greenhouse gases (GHGs) fluxes and examine key factors, which control variation of the GHGs fluxes in the two sites. Net CO(2) and CH(4) fluxes were markedly different between the two sites; magnitudes and variations of the both fluxes in sandy shore were lower than those of salt marsh. Meanwhile, magnitude and variation of net N(2)O flux in the two sites were similar. In sandy shore, temporal and spatial variation of the three GHGs fluxes were highly controlled by water level fluctuation derived from astronomic tide. In salt marsh, spatial variation of the three GHGs fluxes were correlated with aboveground biomass, and temporal variation of CO(2) and CH(4) fluxes were correlated with soil temperature. The sum of global warming potential, which was roughly estimated using the observed GHGs fluxes, was ca. 174-fold higher in salt marsh than in sandy shore. 相似文献
27.
Naoko Yamano Atsuyoshi Nakayama Norioki Kawasaki Noboru Yamamoto Seiichi Aiba 《Journal of Polymers and the Environment》2008,16(2):141-146
We identified a biodegrading microorganism of polyamide (nylon) 4, a linear polymer of γ-aminobutyric acid (GABA). From activated
sludge, the biodegrading bacteria strains of Pseudomonas sp. were isolated and identified by their taxonomic characteristics and nucleotide sequences of 16S rDNA. One strain, ND-11,
was grown on a minimal medium containing polyamide 4 (PA4) as the sole carbon source. The strain produced GABA as a degradation
intermediate, as identified by analyzing the NMR spectra of degraded products. The culture supernatant of strain ND-11 degraded
the emulsified PA4 completely within one day. These results suggest that the ND-11 strain degraded PA4 using its extracellular
enzymes to hydrolyze amide bonds. 相似文献
28.
Andriamanohiarisoamanana Fetra J. Sakamoto Yushi Yamashiro Takaki Yasui Seiichi Iwasaki Masahiro Ihara Ikko Nishida Takehiro Umetsu Kazutaka 《Journal of Material Cycles and Waste Management》2017,19(3):1253-1260
Journal of Material Cycles and Waste Management - The influence of temperature and storage time on hydrogen sulphide (H2S) emissions from two different dairy manures was investigated over four... 相似文献
29.
Aikawa M Hiraki T Tamaki M Kasahara M Kondo A Uno I Mukai H Shimizu A Murano K 《Environmental monitoring and assessment》2006,122(1-3):61-79
An intensive field survey, with 6-h measurement intervals, of concentrations of chemical species in particulate matter and gaseous compounds was carried out at coastal sites on the Sea of Japan during winter. The concentration variation of SO2(g) and HNO3(g) were well correlated, whereas the NH3(g) concentration variation had no correlation with those of SO2(g) and HNO3(g). The NH4
+ (p)/non-sea-salt- (nss-)SO4
2 −(p) ratio in particulate matter was mainly affected by the location of the sampling site. One or more concentration peaks of nss-Ca2 + for survey period were observed. Backward trajectories analyses for the highest nss-Ca2 + concentration peaks showed some inconsistency in pathways. We consider that insufficient mixing of the atmosphere and/or insufficient time for the transported air pollutants to react with those discharged locally are the most likely explanations for the discrepancies between the measured products [HNO3][NH3] and the calculated values. 相似文献
30.
S Uno A Shintoyo E Kokushi M Yamamoto K Nakayama J Koyama 《Environmental science and pollution research international》2011,19(7):2595-2605