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741.
Multiple nuclides commonly occur together and exert toxicity simultaneously, but the difference between single and combined effects of the nuclides is rarely investigated. Epiphytic Tillandsia species are efficient air pollution biomonitors, but rarely used to monitor nuclide contamination. Two Tillandsia species, that is, T. brachycaulos and T. stricta, were chosen to test their capacity to accumulate Cs and Sr. Most plants were able to endure Cs and Sr stress for a long period, which suggested these species could resist toxic elements physiologically and metabolically. With the increasing Cs or Sr concentrations, nuclide contents in both species increased significantly, indicating the potential of Tillandsia species in monitoring nuclide pollutants. However, when the plants were treated with combined nuclides, the content of each ion decreased distinctly compared to those treated with single ion, which suggested Cs and Sr influenced and inhibited each other. In addition, T. brachycaulos seemed more efficient in the uptake of Sr, while T. stricta was more efficient for Cs. Both species accumulated more Sr than Cs at low concentrations, while more Cs than Sr at high concentrations. These results indicated that the uptake of Cs and Sr was related to both the concentrations of the nuclides and the plant species exposed. 相似文献
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Rayan Rabehi Abla Chaker Zeroual Aouachria Ming Tingzhen 《International Journal of Green Energy》2017,14(12):971-982
The solar chimney power plant (SCPP) is a power generator which uses solar radiation to increase the internal energy of the air circulating in the system, thereby transforming the useful gain of the solar collector into kinetic energy. The produced kinetic energy then can be converted into electrical energy by means of an appropriate turbine. In this paper, four locations in Algeria
(Constantine, Ouargla, Adrar, and Tamanrasset) were considered as case studies to describe the SCPP mechanism in detail. Numerical simulation of an SCPP which has the same geometrical dimensions was performed to estimate the power output of SCPP in these regions. Using the CFD software FLUENT we simulated a two-dimensional axisymmetric model of a SCPP with the standard k-ε turbulence model. The simulation results show that the highest power output produced monthly average value 68–73 KW over the year and the highest hourly power produced in June is around 109–113 KW. 相似文献
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Mohamed Kaddari Mahmoud El Mouden Abdelowahed Hajjaji 《International Journal of Green Energy》2017,14(10):839-844
This paper presents potential energy savings by installing high-efficiency motors instead of existing ones and their impact on greenhouse gases emissions reductions. This research study of the energy efficiency of electric motors has been performed in a typical thermal power plant. In the literature, the focus has been mainly on separate and away electric motors from operating facilities. The important advantage of this paper over other studies is that it uses the actual motors’ efficiency in the evaluation. The gains both in terms of electrical energy savings and in terms of financial economy by using high-efficiency motors have been discussed. As a result, the energy saving can be expected as 12.6% at the operating rate. This excellent result also reduces greenhouse gas emission by 1,423 tons every year. The analysis of the data provided an overview on energy losses often generated by the degradation and rewinding of electrical motors. This study represents very encouraging results that will help energy managers of industrial plants to become more involved in energy efficiency strategies. 相似文献
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Ahmet Z. Sahin Shafiqur Rehman Fahad Al-Sulaiman 《International Journal of Green Energy》2017,14(5):490-498
Daily global solar radiation on a horizontal surface and duration of sunshine hours have been determined experimentally for five meteorological stations in Saudi Arabia, namely, Abha, Al-Ahsa, Al-Jouf, Al-Qaisumah, and Wadi Al-Dawaser sites. Five-years of data covering 1998–2002 period have been used. Suitable Angstrom models have been developed for the global solar radiation estimation as a function of the sunshine duration for each respective sites. Daily averages of monthly solar PV power outputs have been determined using the Angstrom models developed. The effect of the PV cell temperature on the PV efficiency has been considered in calculating the PV power output. The annual average PV output energy has been discussed in all five sites for small loads. The minimum and maximum monthly average values of the daily global solar radiation are found to be 12.09 MJ/m2/d and 30.42 MJ/m2/d for Al-Qaisumah and Al-Jouf in the months of December June, respectively. Minimum monthly average sunshine hours of 5.89 hr were observed in Al-Qaisumah in December while a maximum of 12.92 hr in Al-Jouf in the month of June. Shortest range of sunshine hours of 7.33–10.12 hr was recorded at Abha station. Minimum monthly average Solar PV power of 1.59 MJ/m2/day was obtained at Al-Qaisumah in the month of December and a maximum of 3.39 MJ/m2/day at Al-Jouf in June. The annual PV energy output was found to be 276.04 kWh/m2, 257.36 kWh/m2, 256.75 kWh/m2, 245.44 kWh/m2, and 270.95 kWh/m2 at Abha, Al-Ahsa, Al-Jouf, Al-Qaisumah, and Wadi Al-Dawaser stations, respectively. It is found that the Abha site yields the highest solar PV energy among the five sites considered. 相似文献
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