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651.
Russian Journal of Ecology - 相似文献
652.
The effects of Cu2+, Cd2+, and Ni2+ at low and high concentrations (0.025 and 0.25 mg/ml) on the accumulation capacity, the state of the pigment complex, and photosynthesis rate have been studied in model experiments with three floating hydrophytes (Hydrocharis morsus-ranae L., Lemna gibba L., and Potamogeton natans L.) and four submerged hydrophytes (Elodea canadensis Michx., Lemna trisulka L., Ceratophyllum demersum L., and Potamogeton lucens L.). Copper and cadmium are especially toxic at the concentrations studied. The effect of Cu2+ was the strongest in hydatophytes, and the effect of Cd2+, in pleustophytes. It is hypothesized that the differences between hydrophytes with respect to accumulation of metals and decrease in photosynthesis rate may cause predominant elimination of submerged species. Therefore, changes in the species structure of hydrophyte communities may be expected in waters polluted with metals. 相似文献
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654.
The transfer of radiocaesium, one of the most important and widespread contaminants following a nuclear accident, to the fibre crops hemp (Cannabis sativa L.) and flax (Linum usitatissimum L.) as well as the distribution of radiocaesium during crop conversion were studied for sandy soil under greenhouse and lysimeters conditions. Soil parameters did not unequivoqually explain the transfer factors (TF) observed. TFs to flax stems ranged from 1.34 to 2.80x10(-3) m2 kg(-1). TFs to seeds are about a factor of 4 lower. During the retting process for separating the fibres from the straw, more than 95% of the activity was removed with the retting water. For hemp, the TF to the stem was about 0.6x10(-3) m2 kg(-1). For hemp, straw and fibres were mechanically separated and TF to straw was about 0.5x10(-3) m2 kg(-1) and to fibres 1.0x10(-3) m2 kg(-1). Generally, the TFs to the useable plant parts both for hemp and flax, are low enough to allow for the production of clean end-products (fibre, seed oil, biofuel) even on heavily contaminated land. Given the considerable decontamination during retting, contamination levels in flax fibres would only exceed the exemption limits for fibre use after production in extreme contamination scenarios (>12,300kBq m(-2)). Since hemp fibres are mechanically separated, use of hemp fibres is more restricted (contamination <740kBq m(-2)). Use of stems as biofuel is restricted to areas with contamination levels of <250 and 1050kBq m(-2) for flax and hemp, respectively. Use of seeds for edible oil production and flour is possible almost without restriction for flax but due to the high TFs to seed observed for hemp (up to 3x10(-3) m2 kg(-1)) consumption of hemp seed products should be considered with care. 相似文献
655.
In this paper deposition rate coefficients for unattached and attached radon progeny were estimated according to a particle deposition model for turbulent indoor airflow described by Zhao and Wu [2006. Modeling particle deposition from fully developed turbulent flow in ventilation duct. Atmos. Environ. 40, 457–466]. The parameter which characterizes turbulent indoor airflow in this model is friction velocity, u*. Indoor ventilation changes indoor airflow and friction velocity and influences deposition rate coefficients. Correlation between deposition and ventilation rate coefficients in the room was determined. It was shown that deposition rate coefficient increases with ventilation rate coefficient and that these parameters of the Jacobi room model cannot be assumed to be independent. The values of deposition rate coefficients were presented as functions of friction velocity and ventilation rate coefficient. If ventilation rate coefficient varies from 0.1 up to 1 h−1, deposition rate coefficients for unattached and attached fractions were estimated to be in the range 3–110 h−1 and 0.015–0.35 h−1, respectively. 相似文献
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658.
Kaur Ishnoor Behl Tapan Sehgal Aayush Singh Sukhbir Sharma Neelam Subramanian Vetriselvan Fuloria Shivkanya Fuloria Neeraj Kumar Sekar Mahendran Dailah Hamed Ghaleb Alsubayiel Amal M. Bhatia Saurabh Al-Harrasi Ahmed Aleya Lotfi Bungau Simona 《Environmental science and pollution research international》2022,29(45):67685-67703
Environmental Science and Pollution Research - The 2019 outbreak of corona virus disease began from Wuhan (China), transforming into a leading pandemic, posing an immense threat to the global... 相似文献
659.
Yohannes Yared Beyene Nakayama Shouta M. M. Yabe John Toyomaki Haruya Kataba Andrew Nakata Hokuto Muzandu Kaampwe Ikenaka Yoshinori Choongo Kennedy Ishizuka Mayumi 《Environmental science and pollution research international》2022,29(5):6622-6632
Environmental Science and Pollution Research - Interindividual genetic variations determine human’s susceptibility to heavy metal-induced toxicity. Thus, we analyzed blood concentrations of... 相似文献
660.
Attia Youssef A. Giorgio Gianpaolo M. Addeo Nicola F. Asiry Khalid A. Piccolo Giovanni Nizza Antonino Di Meo Carmelo Alanazi Naimah A. Al-qurashi Adel D. El-Hack Mohamed E. Abd Khafaga Asmaa F. Bovera Fulvia 《Environmental science and pollution research international》2022,29(7):9592-9605
Environmental Science and Pollution Research - COVID-19 pandemic has passed to the front all the contradictions of the beekeeping sector: the valuable role of bee products as immune enhancers and... 相似文献