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181.
Sizing a new reservoir is a challenging task, which normally requires simultaneously a cost-effective, risk-informed, and forward-looking decision analysis with respect to basin-wide hydrological features, environmental quality, and biological integrity. Such a sustainable planning approach takes into account the global trend to balance the needs of economic growth, ecological conservation, and environmental protection. To achieve the goal of sustainability, emphasis in this paper was placed upon the correlation of three physical, chemical, and biological indices, including the dissolved oxygen (DO), the 5-day biochemical oxygen demand (BOD5), and the index of biotic integrity (IBI), for the optimal planning of a reservoir in a river basin. This new methodological paradigm has been employed for sizing an off-stream reservoir in the Hou-Lung River Basin, central Taiwan. The internal linkage between the water quality parameters (DO and BOD5) and the IBI levels further enables us to formulate a special biotic integrity constraint which reflects fish community attributes to suit a relatively low-density and unspecialized freshwater fish fauna in response to the changing water quality conditions in the river basin. The tradeoffs among economic, environmental, and ecological aspects for reservoir sizing can then be based on the river flow patterns, the water demand, the water quality standards, and the anticipated biological integrity in some critical river reaches. Findings in a preliminary case study suggest that an optimal pumping scheme may be smoothly maintained on a yearly basis within a combined multicriteria and multiobjective decision-making process.  相似文献   
182.
Aerobiological studies in commuting trains in northern Taiwan were carried out from August, 2007 until July, 2008. Two six-stage (>7 μm, 4.7~7 μm, 3.3~4.7 μm, 2.1~3.3 μm, 1.1~2.1 μm, 0.65~1.1 μm) cascade impactors of 400 orifices were used to collect viable bacteria and fungi, respectively. The levels of carbon monoxide (CO), carbon dioxide (CO2), formaldehyde (HCHO), temperature, and relative humidity in the commuting trains were also recorded during the sampling period. Results show that bacterial concentrations ranged from 25 to 1530 CFU m?3, and averaged 417 CFU m?3. The fungal concentrations ranged from 45 to 1906 CFU m?3, and averaged 413 CFU m?3. Additionally, the highest fractions occurred in the fifth stage (1.1~2.1 μm) for both bacteria and fungi. The respirable fractions, Rb and Rf, for bacteria and fungi were 62.8% and 81.4%, respectively, which are higher than those in other studies. Furthermore, the bacterial concentration reached its highest level in autumn, and its lowest level in winter. However, the fungal concentration was highest in spring and lowest in winter. Though the total bacterial or fungal concentration did not exceed the recommendation standard in Taiwan, the relatively high respirable fraction in commuting trains probably implies a higher adverse health risk for sensitive commuters. This study further conducted multiple regression analysis to determine the relationship of various stage fractions of airborne bacteria and fungi with indoor air pollutants (CO and HCHO) and environmental parameters (CO2, temperature, and relative humidity). The correlation coefficients of multiple regression analysis for total bacteria and fungi concentrations with indoor air pollutants and environmental parameters were 0.707 (p < 0.00376) and 0.612 (p < 0.00471), respectively. There are currently no formally regulated laws for indoor air quality (IAQ) in Taiwan, and this preliminary study can provide references to the Taiwan government on IAQ management.  相似文献   
183.
Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic compounds that have emerged as chemicals of concern in drinking water and groundwater. Typically, such waters are treated to remove PFAS by passing the water through a bed of sorbent material (e.g., activated carbon and anion exchange resins [AIX]). However, the efficacy of these sorbents varies depending on the types and concentrations of PFAS, in addition to water quality conditions such as organic matter content and conductivity (ionic strength). The choice of sorbent material to effectively treat PFAS in complex natural waters will, therefore, depend upon site water quality and PFAS conditions. To help inform these decisions, a series of evaluations using a rapid small-scale column test approach was conducted with two sorbent materials (a granulated activated carbon [GAC] and an AIX), individually and combined, under conditions where conductivity, pH, and organic carbon concentrations were varied in a semifactorial approach. Artificial groundwater batches were prepared to meet these test conditions and spiked with six PFAS compounds (perfluorobutane sulfonic acid [PFBS], perfluorobutanoic acid [PFBA], perfluorohexane sulfonic acid [PFHxS], perfluorohexanoic acid [PFHxA], perfluorooctane sulfonic acid [PFOS], and perfluorooctanoic acid [PFOA]), passed through small columns packed with ground sorbent material for ∼30,000 bed volumes of water for single sorbent treatments and ∼20,000 bed volumes for combined sorbent treatments, during which samples of effluent were captured and analyzed to quantify breakthrough of PFAS from the sorbent materials over time. AIX was found to be more effective than GAC at removing the tested perfluoroalkyl sulfonic acids (PFBS, PFHxS, and PFOS), but GAC was similarly or more effective than AIX at removing perfluorocarboxylic acids (PFBA, PFHxA, and PFOA) under high conductivity conditions. Overall, the efficacy of AIX at removing PFAS was more strongly impacted by organic carbon and conductivity than GAC, while pH had less of an effect on either sorbent's efficacy compared to the other test conditions.  相似文献   
184.
This paper investigates the confluence of humanitarian aid, centralisation, and politics. The 7.0 magnitude earthquake in Haiti on 12 January 2010 led to more than USD 16 billion in pledges. By contrast, Hurricane Matthew, which made landfall in Haiti on 4 October 2016, stayed in the shadows, attracting about one per cent of the amount. While the earthquake exhibited one face of centralisation, the Category 4 storm laid bare rural vulnerabilities shaped by postcolonial state neglect, and reinforced by the influx of non-governmental organisations in the ‘Republic of Port-au-Prince’. The study draws on data from four case studies in two departments to illuminate the legacies of hyper-centralisation in Haiti. Compounding matters, Matthew struck in the middle of an extended election that the international community attempted to control again. The paper argues that disaster assistance and politics are uncomfortably close, while reflecting on the momentary decentralisation of aid after the hurricane and its effectiveness.  相似文献   
185.
Copper, zinc, and cerium oxide adsorbents supported on alumina were used to remove silane gas (SiH4). The adsorbents were prepared using a coprecipitation method and characterized by the inductively coupled plasma mass spectrometry, X-ray powder diffractometer, and Brunauer-Emmett-Teller method (BET). The silane removal efficiency and adsorption capacity of the adsorbents were investigated in this study. Test results showed that the adsorbents containing active species had a removal efficiency >99.9% for SiH4 before breakthrough. Adsorbents containing mixed oxides (CuO-CeO2/ Al2O3 and CuO-ZnO/Al2O3), which showed well-dispersed active species and high BET surface areas, had a greater adsorption capacity than the adsorbents containing single metal oxide. However, when the CuO-ZnO/ Al2O3 adsorbents contain >40 wt% of active metal oxides, the increase of active species lowered the BET surface area leading to a decrease of the adsorption capacity. Additionally, when the content of the active metal oxides was between 20% and 40%, the CuO-ZnO/Al2O3 adsorbents demonstrated higher adsorption capacity.  相似文献   
186.
Chien LC  Yeh CY  Jiang CB  Hsu CS  Han BC 《Chemosphere》2007,67(1):29-35
The US Food and Drug Administration (USFDA) and Environmental Protection Agency (USEPA) are advising women and young children to avoid eating fish that contain high levels of mercury (Hg). However in Taiwan, the annual Black Fin Tuna Festival encourages the public to consume fish. The aim of this study was to assess fish intake in relation to the health risks of mercury exposure and calculate the acceptable and safe intake of fish in children and women of childbearing age. From the Monte Carlo simulation, based on USEPA's reference dose (0.1 microgkg(-1)d(-1)), we found that 21.6%-24.3% and 45.6%-57.4% of the daily mercury dose estimates exceeded the reference dose for typical and high-seafood consumers. The acceptable ingestion rates are <50 g d(-1) (children) and 90.8 +/- 15.7 g d(-1) (women of childbearing). Sensitivity analysis suggests that Hg concentration in fish may be a key parameter to aid governments as they offer guidance for risk management.  相似文献   
187.
Hsu BM  Chen CH  Kung CM  Wan MT  Shen SM 《Chemosphere》2007,66(5):964-969
The performance of six concentration method combinations and two quantitative analysis techniques were evaluated in terms of enterovirus recovery efficiencies by adjusting the pH and salt concentration of water samples. Of the six concentration method combinations, adsorption on nitrocellulose membranes followed by an acid rinse elution consistently gave the highest recovery efficiencies. In theory, an electropositive membrane should be the most appropriate technique for adsorption of electronegative viruses in pure water. However, it displayed the greatest loss in natural waters. For adsorption and elution procedures, both the electronegative membrane, accompanied by an acid rinse step, and the electropositive membrane, accompanied by a glycine rinse step, provided higher recovery efficiencies. MPN-RT-PCR, a statistically quantitative analysis method, performed more efficiently, in economic terms, but had a similar enterovirus recovery trend to real-time RT-PCR, which is the authoritative quantitative analysis method for nucleic acid.  相似文献   
188.
The use of pharmaceuticals during pregnancy may causes abnormalities to the embryo. Sometime the drug also effect to the new born if the drug transferred through lactation. We have used zebrafish model to see the effect of some pharmaceuticals on embryos and larvae. Three drugs, caffeine, norfloxacin and nimesulide, were used for this study to see the effect mainly the hatching rate of eggs, heart beat rate and the vascular endothelial growth factor (VEGF) expression of the larvae. VEGF is an important signaling protein that involved generating the new blood vessels during embryonic development. We have used 10, 20, 50, 100 microg ml(-1) concentrations of all the drugs to see the effect. No significant mortality or malformations were observed in zebrafish embryos. Hatching was stared from 60 hr. In control group, 91% hatching rate was observed. Lowest hatching rate was observed using highest concentration of norfloxacin (100 microg ml(-1)) and nimesulide (100 microg ml(-1)) i.e. 55 and 56% respectively. In control group, 110 to 115 heart beat rate was counted per minute. Significantly higher heart beat was observed in caffeine treated group which is 125 to 140 min(-1) Lower heart beat was noted in nimesulide treated group which is 100 min(-1). We have tried to observe the possible effect of VEGF of the larvae by these three drugs. Expression of VEGF was very low in caffeine treated group. Almost no VGF expression was observe in 100 microg ml(-1) caffeine treated group. These studies suggest that there is a possibility that high dosage of caffeine can harm the unborn baby or new born babies, if the mothers use caffeine.  相似文献   
189.
Environmental Science and Pollution Research - This research aims to look into the effect of COVID-19 on emerging stock markets in seven of the Association of Southeast Asian Nations’...  相似文献   
190.
The use of a biodegradable natural plant-based surfactant extracted from soapberry is proposed for the remediation of Ni, Cr and Mn from industrial soil site in Hai-Pu, Taiwan. Batch experiments were performed under variation of fundamental factors (saponin concentration, pH, and incubation time) for metal remediation. Removal of Ni and Mn were increased with increasing saponin concentration (0.015-0.150 g/L), whereas the removal of Cr was increased upto 0.075 g/L saponin. The Ni, Cr and Mn were removed significantly (p ≤q 0.05) at near to the neutral and slightly acidic (pH 5 to 8) conditions. Removal efficiency of Ni (99%) from the soil was found to be greater than that of Cr (73%) or Mn (25%) in the presence of saponin at a concentration of 0.150 g/L at pH 5. The removal percentage increased with incubation time where the removal of Ni was faster than that of Cr and Mn. The result indicates the feasibility of eco-friendly removal of heavy metal (Ni, Cr and Mn) from industrial soil by soil washing process in presence of plant derived saponin.  相似文献   
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