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31.
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   
32.
The 2005 hurricane season caused extensive damage and induced a mass migration of approximately 1.1 million people from southern Louisiana in the United States. Current and accurate estimates of population size and demographics and an assessment of the critical needs for public services were required to guide recovery efforts. Since forecasts using pre-hurricane data may produce inaccurate estimates of the post-hurricane population, a household survey in 18 hurricane-affected parishes was conducted to provide timely and credible information on the size of these populations, their demographics and their condition. This paper describes the methods used, the challenges encountered, and the key factors for successful implementation. This post-disaster survey was unique because it identified the needs of the people in the affected parishes and quantified the number of people with these needs. Consequently, this survey established new population and health indicator baselines that otherwise would have not been available to guide the relief and recovery efforts in southern Louisiana.  相似文献   
33.

The fate of pharmaceuticals after discharged from hospital into wastewater was clarified experimentally by using a new lab-scale conventional activated sludge (CAS) treatment reactor. The 43 target compounds belong to nine therapeutic classes (antivirals, antibacterials, anticancer drugs, psychotropics, antihypertensives, analgesic–antipyretics, contrast media, herbal medicines, and phytoestrogens) were selected with inclusion of 16 newly estimated compounds. The efficiency of the present reactor was estimated by comparing the reaction rate constant of the solid-water partition coefficients (log Kd) between liquid and solid samples and half-life during 48-h experiment obtained by using hospital effluents with those obtained by using STP wastewater. The results that no significant difference in removal efficiency was observed between both water samples (P?>?0.05) indicate high reliability of the present lab-scale reactor. The actual rates of removal when hospital effluent was applied varied widely (mean, 59?±?40%) independent of type of the pharmaceuticals. More than 90% of 17 compounds were removed after 8 h of treatment. However, the values for psychotropics (mean, 19?±?26%) and contrast media (mean, 24?±?17%) were generally low, indicating high stability. The log Kd values ranged from 1.3 to 4.8. Notably, clarithromycin, acridine, and glycitein could be removed in both liquid and solid phases. The dominant removal mechanisms were found to be different for individual pharmaceutical. These results suggest the effectiveness of introduction of the lab-scale biological treatment system for development of a new solution for discharge of pharmaceuticals from hospital.

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The dehydrochlorination behavior of plasticizer (DOP) and inorganic filler (CaCO3) contained in PVC samples and the properties of the activated carbons produced from those carbon residues have been investigated. In the dehydrochlorination process, both additives contributed not only to a decrease in HCl yield but also to the prolonged evolution of HCl. Part of the Cl species were observed to be stabilized as CaCl2 by reaction with calcium ions when CaCO3 was added. More than 80% of chlorine removal was achieved in all samples at 533 K. The use of potassium as an activation agent led to the production of activated carbon with a specific surface area greater than 1000 m2/g at the low temperature of 1023 K and assisted also in the elimination of residual Cl species by the formation of KCl during activation. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6  相似文献   
36.
Distributions of serotonin and catecholamines in larvae of the marine bryozoan Bugula neritina (Bryozoa: Cheilostomatida) were investigated using immunohistochemistry with anti-serotonin antiserum and glyoxylic acid–induced fluorescence histochemistry. Anti-serotonin immunoreactive substances and glyoxylic acid–induced fluorescent substances had similar distributions in the equatorial neuromuscular ring, the neural plexus, the paired axial neuromuscular cords, and tracts connecting the neural plexus to ciliated cells bordering the pyriform organ. The effects of dopamine, noradrenaline, adrenaline, tyramine, octopamine, synephrine and serotonin, at 10−4, 10−5 and 10−6M, on settlement were analysed. In filtered seawater, 98% of larvae settled in 3 h, but only 11%, 3% and 6% total settlement was observed after 8 h in 10−4M dopamine, 10−4M serotonin and 10−5M serotonin, respectively. Total settlement was 70% in 10−4M noradrenaline, 80% in 10−4M adrenaline and 60% in 10−4M tyramine. Less than 60% settlement was observed in 10−4 and 10−5M octopamine and synephrine. Serotonin's inhibitory effect on settlement was mimicked by a range of serotonin receptor agonists and antagonists, among which 5-carboxamidotryptamine was the most potent. Received: 19 March 1999 / Accepted: 11 October 1999  相似文献   
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Measures of niche overlap are used to assess the similarity or dissimilarity of two populations. Matusita's measure is one of commonly used niche overlap measures. We consider the problem of estimating Matusita's measure when samples are from multivariate normal distributions with unknown mean vectors and covariance matrices. Asymptotic variances and biases of Matusita's measure estimates are derived and bias reduction methods are proposed. Simulation results are shown to illustrate characteristics of the estimates and bias reduction methods.  相似文献   
39.
We evaluated the impacts of natural wetlands and various land uses on stream nitrogen concentration in two grassland-dominated catchments in eastern Hokkaido, Japan. Analyzing land use types in drainage basins, measuring denitrification potential of its soil, and water sampling in all seasons of 2003 were performed. Results showed a highly significant positive correlation between the concentration of stream NO3-N and the proportion of upland area in drainage basins in both catchments. The regression slope, which we assumed to reflect the impact on water quality, was 24% lower for the Akkeshi catchment (0.012 +/- 0.001) than for the Shibetsu catchment (0.016 +/- 0.001). In the Akkeshi catchment, there was a significant negative correlation between the proportion of wetlands in the drainage basins and stream NO3-N concentration. Stream dissolved organic nitrogen (DON) and carbon (DOC) concentrations were significantly higher in the Akkeshi catchment. Upland and urban land uses were strongly linked to increases in in-stream N concentrations in both catchments, whereas wetlands and forests tended to mitigate water quality degradation. The denitrification potential of the soils was highest in wetlands, medium in riparian forests, and lowest in grasslands; and was significant in wetlands and riparian forests in the Akkeshi catchment. The solubility of soil organic carbon (SOC) and soil moisture tended to determine the denitrification potential. These results indicate that the water environment within the catchments, which influences denitrification potential and soil organic matter content, could have caused the difference in stream water quality between the two catchments.  相似文献   
40.
In order to establish energy-saving technology for CO2 capture from blast furnace gas, novel absorbents were developed in the laboratory and evaluated at a 1 tCO2/d test plant. At first, CO2 absorption and desorption behaviors of single-component amine solvents for simulated blast furnace gas (CO2/N2 = 20%/80%) were investigated through a screening test using a small scrubbing bottle. These amine solvents were additionally analyzed using nuclear magnetic resonance (13C NMR) spectroscopy and reaction calorimetry. The results of the laboratory experiments showed that there was a trade-off between absorption rate and enthalpy of absorption but some absorbents had unique features. For example, 2-isopropylaminoethanol (IPAE) had high absorption rate and small enthalpy of absorption. Then, new IPAE-based amine solvents (RITE solvents: RITE-A and RITE-B) were formulated and evaluated at the 1 tCO2/d test plant. CO2 regeneration energies of the RITE solvents were 3.3 and 3.1 GJ/tCO2, respectively. With certain process conditions and plant specifications optimized, RITE-B was estimated to have the potential to achieve 2.5 GJ/tCO2.  相似文献   
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