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1.
Souad A. Elfeky Hisham Imam Alsayed A. Alsherbini 《Environmental science and pollution research international》2013,20(11):8220-8226
Release of heavy metals into waterways without treatment can cause a significant threat to the environment. In this paper, we present a method of improving the removal of heavy metals by using Eichhornia crassipes roots (ECR) supported on a polymethyl methacrylate (PMMA) thin film. The functional groups of the synthesized PMMA sample were identified by Fourier transform infrared spectroscopy. ECR roots dried fine powder has a small size and large surface area. They contain many polyfunctional metal-binding sites for both cationic and anionic metal complexes. The results show that using 0.1 g of ECR, about 70 % of Cd present in the water was removed in 4 h; while under the same conditions, about 55 % of Ni was removed. The concentrations of Ni and Cd were measured by laser-induced breakdown spectroscopy, a promising technique for the elemental analysis of heavy metals. 相似文献
2.
Zina Armi Souad Turki Elbahri Trabelsi Naceur Ben Maiz 《Environmental monitoring and assessment》2010,164(1-4):423-433
Coolia monotis is a potentially toxic epiphytic dinoflagellate widespread along the Mediterranean coasts, where it is frequently detected year round at low concentrations. However, it only proliferates recurrently in some localities. The North Lake of Tunis is one of the affected areas in the southwestern part of the Mediterranean Sea. This site is one of the most productive aquatic Tunisian areas (Recreational Fisheries and shellfish collecting). In the south part of this area of study, recurrent C. monotis proliferation (5 ×105 cells per liter) took place in late spring and early summer of 2006. During this proliferation, the spatial distribution of C. monotis species, phytoplankton community, and abiotic factors were studied. The composition of the phytoplankton community exhibited a clear dominance of dinoflagellates over other genera. We suggest that proliferation development of C. monotis was linked to climatic conditions, water temperature (r?=?0.24, p?<?0.05) and high concentrations of nitrogenous nutrients, essentially NH4 ?+? (r?=?0.18, p?<?0.05) and NO3 ??? (r?=?0.21, p?<?0.05). 相似文献
3.
Belabed Bourhane-Eddine Frossard Victor Dhib Amel Turki Souad Aleya Lotfi 《Environmental monitoring and assessment》2013,185(12):9905-9915
A study of trace metal (TM) contamination was conducted at Lake Tonga (Algeria), a site surrounded by several indirect contamination point sources such as an abandoned mine and steelworks. Studying two sampling sites over four seasons, we were able to depict the spatial and temporal variability of TM contamination in the lake. Among the seven TM examined (Pb, Cd, Fe, Zn, Ni, Cu, and Cr), only Fe, Pb, and Cd showed concentrations significantly higher than the site’s geological background. The contamination index (sediment concentration/background concentration) calculated for these three TM (Cd = 1.9?±?1.6, Fe = 6.8?±?1.8, and Pb = 3.3?±?2.6) clearly indicated anthropogenic contamination. Sediment TM contamination differed both between sampling sites and seasons despite environmental variables (e.g., oxygen and pH) being similar, thus suggesting different TM contamination sources. Fe contamination was high at the two sampling sites and over all studied seasons, possibly indicating general lake-scale Fe contamination, probably related to atmospheric deposition of steelworks emissions both on the lake and within the watershed. Lake tributaries were further suspected of channeling Fe contamination from the watershed into the lake. On the other hand, the sampling site close to the outlet was especially rich in Cd and Pb typically reflecting contamination by mine wastes. The indirect connection between the abandoned mine and the lake indicates that runoff of mine leachates through groundwater was likely a candidate in explaining the specificity of the TM contamination in this part of the lake. This study provides insights for management of TM contamination by addressing both spatial and temporal variability within the lake as well as differences in contamination sources. 相似文献
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Yakkou Lamia Houida Sofia Bilen Serdar Kaya Leyla Okyay Raouane Mohammed Amghar Souad Harti Abdellatif El 《Environmental science and pollution research international》2023,30(5):11719-11739
Environmental Science and Pollution Research - This study evaluated the impact of Aporrectodea molleri's coelomic fluid-associated bacteria (CFB) on Zea mays L. growth and soil biochemical... 相似文献
6.
Awatef Aissaoui Zina Armi Souad Turki Oum Kalthoum Ben Hassine 《Environmental monitoring and assessment》2013,185(11):9361-9384
This study investigates spatio-temporal variations of in situ division rate (μ) of two species of the genus Dinophysis. Based on a postmitotic index approach, estimates of μ from net-haul samples were compared during five daily cell cycles studies in three stations of the Punic harbors of Carthage (Gulf of Tunis). To study the annual cycle of Dinophysis spp., weekly sampling were carried out from March 2008 to June 2010. In addition, sampling over 24 h was conducted on three-cycle studies in late spring and two-cycle studies in autumn, seasons characterized by Dinophysis proliferations. We recorded important abundances of Dinophysis sacculus stein (2.25?×?104 cells/l, June 2008) and Dinophysis cf. acuminata (3?×?104 cells/l, June 2009). Cellular division was phased in D. sacculus stein and D. cf. acuminata, but the division time, required for the population cohorts to pass from one phase to another, and values of estimated division rates varied between seasons and stations for the same species. D. cf. acuminata exhibit moderate (0.22 day?1) to high (0.68 day?1) value of μ. In contrast, D. sacculus shows very low μ values (0.02–0.17 day?1) in autumn season to moderate values (0.21–0.35 day?1) in late spring. The results presented here confirm that the postmitotic index approach allowed estimated of μ at low field depths and concentrations (102–103 cells/l). 相似文献
7.
Activated carbon was produced from olive stones(OSAC) by a physical process in two steps. The adsorption character of this activated carbon was tested on three colour dyes molecules in aqueous solution: Methylene blue(MB), Rhodamine B(RB) and Congo Red(CR). The adsorption equilibrium was studied through isotherms construction at 30℃, which were well described by Langmuir model. The adsorption capacity on the OSAC was estimated to be 303 mg/g, 217 mg/g and 167 mg/g respectively for MB, RB and CR. This activated carbon has a similar adsorption properties to that of commercial ones and show the same adsorption performances. The adsorption kinetics of the MB molecule in aqueous solution at different initial concentrations by OSAC was also studied. Kinetic experiments were well fitted by a simple intra-particle diffusion model. The measured kinetics constant was influenced by the initial concentration and we found the following correlation: Kid = 1.55 C0^0.51. 相似文献
8.
Synthesis and characterization of drinking water treatment plant sludge-incorporated Portland cement
Mohammed Dahhou Mohammed El Moussaouiti Muhammad Azeem Arshad Souad Moustahsine Mohamed Assafi 《Journal of Material Cycles and Waste Management》2018,20(2):891-901
Kinetic analysis of thermally activated phase transformations in drinking water treatment plant (DWTP) sludge suggests its applicability in the materials of construction. The suggested prediction has already been verified on the sludge-based bricks. The present study deals with incorporating the same sludge in the raw meal for the synthesis of Portland cement clinkers. For this purpose, two raw meals are prepared with varying sludge loadings. The sludge effect on reactivity of the crude mixture is evaluated on the basis of the free lime content sintered at various elevated temperatures. The results of chemical and mineralogical and scanning electron microscopic analyses reveal fine mineralogical contents of Portland clinkers calcined at 1450 and 1500 °C. Moreover, the cements prepared from these clinkers by the introduction of certain proportions of gypsum, depict significant durability. The obtained results elucidate that the studied DWTP sludge-incorporated Portland cement shows considerable potential to be commercialized. 相似文献
9.
Khannyra Souad Gil Maria Luisa Almoraima Addou Mohammed Mosquera Maria Jesus 《Environmental science and pollution research international》2022,29(42):63112-63125
Environmental Science and Pollution Research - In this study, the newly synthesized TiO2 and N doped TiO2 clusters were added to silica sol to synthesize N-TiO2/SiO2 composites via the... 相似文献
10.
Malika?ChlaidaEmail author Souad?Kifani Philippe?Lenfant Lahoussine?Ouragh 《Marine Biology》2006,149(2):169-175
This study aimed at contributing to the identification of the sardine populations in the Moroccan Atlantic. The approach used is enzymes electrophoresis (allozymic marker analysis). The analysis was conducted in seven stations (251 individuals analysed). Two enzymes were tested (LDH* and SOD*). Only the SOD* was polymorphic and highly informative. Statistical analysis results showed heterogeneity between samples. Homogeneous population was identified in the south, from Tarfaya to Dakhla (~28°–24°N). The sampling from Safi (~32°N) seems to come from a differentiated population. The Agadir (~30°N) population would overlap the previous ones. The population identified offshore of Larache (~35°N) would be similar to the population located south of Portugal (~37°N). 相似文献