A broad screening protocol, covering the most general phytochemical groups of compounds, was developed on the basis of high performance thin layer chromatography (HPTLC). A total of six TLC systems, comprising three derivatization reagents, two stationary phases and two mobile phases, were included. The screening method was applied for the identification of biomarkers in the chickpea plant exposed to cadmium and chromium. The biomarkers were selected on the basis of significant changes (0.26-4.6 fold) in concentration levels of phytochemicals. Totally, five different amino acids, three organic acids, one sulphur containing compound and one sugar were identified as biomarkers in chickpea exposed heavy metal. 相似文献
Calendula alata plants were tested for their potential to remove stable cesium and lead from solutions in a 15-day period. The plants were grown hydroponically and placed in solutions containing CsCl and Pb(C?H?O?)? at different concentrations (0.6, 2 and 5 mg l?1). When plants were incubated in CsCl solutions 46.84 ± 2.12%, 41.35 ± 1.59%, and 52.06 ± 1.02% cesium was found to be remediated after 15 days. Moreover, more than 99% lead was removed from the Pb(C?H?O?)? solution in all three concentrations after 15 days during the same period. When both CsCl and Pb(C?H?O?)? were supplemented together in the solution, 9.92 ± 1.22%, 45.56 ± 3.52%, and 46.16 ± 1.48% cesium and 95.30 ± 0.72%, 96.64 ± 0.30%, and 99.02 ± 0.04% lead were removed after 15 days. The present study suggests that hydroponically grown C. alata could be used as a potential candidate plant for phytoremediation of cesium and lead from solutions; however, plants were found to be more efficient for the remediation of lead than cesium. 相似文献
Available water quality indices have some limitations such as incorporating a limited number of water quality variables and providing deterministic outputs. This paper presents a hybrid probabilistic water quality index by utilizing fuzzy inference systems (FIS), Bayesian networks (BNs), and probabilistic neural networks (PNNs). The outputs of two traditional water quality indices, namely the indices proposed by the National Sanitation Foundation and the Canadian Council of Ministers of the Environment, are selected as inputs of the FIS. The FIS is trained based on the opinions of several water quality experts. Then the trained FIS is used in a Monte Carlo analysis to provide the required input-output data for training both the BN and PNN. The trained BN and PNN can be used for probabilistic water quality assessment using water quality monitoring data. The efficiency and applicability of the proposed methodology is evaluated using water quality data obtained from water quality monitoring system of the Jajrood River in Iran. 相似文献
Understanding the groundwater quality is important as it is the main factor determining its suitability for drinking, domestic, agricultural, and industrial purposes. In order to assess the groundwater quality, 30 groundwater samples have been collected in year 2008. The water samples collected in the field were analyzed for electrical conductivity, pH, total dissolved solids (TDS), major cations like calcium, magnesium, sodium, potassium, and anions like bicarbonate, carbonate, chloride, nitrate, and sulfate, in the laboratory using the standard methods given by the American Public Health Association. The groundwater locations were selected to cover the entire study area and attention was been given to the area where contamination is expected. The expected groundwater contaminants were chloride, nitrate, TDS, etc. The results were evaluated in accordance with the drinking water quality standards given by the World Health Organization (WHO 1993). To know the distribution pattern of the concentration of different elements and to demarcate the higher concentration zones, the contour maps for various elements were also generated, discussed, and presented. 相似文献
In the present study, a total of 198 bacteria were isolated, 88 from the tannery effluents and 110 from agricultural soil irrigated with the tannery effluents. Tannery effluents and soils were analyzed for metal concentrations by atomic absorption spectrophotometer. The tannery effluents and soil samples were found to be contaminated with chromium, nickel, zinc, copper, and cadmium. All isolates were tested for their resistance against Cr6?+?, Cr3?+?, Ni2?+?, Zn2?+?, Cu2?+?, Cd2?+?, and Hg2?+?. From the total of 198 isolates, maximum bacterial isolates were found to be resistant to Cr6?+? 178 (89.9%) followed by Cr3?+? 146 (73.7%), Cd2?+? 86 (43.4%), Zn2?+? 83 (41.9%), Ni2?+? 61 (30.8%), and Cu2?+? 51 (25.6%). However, most of the isolates were sensitive to Hg2?+?. Among the isolates from tannery effluents, 97.8% were resistant to Cr6?+? and 64.8% were resistant to Cr3?+?. Most of the soil isolates were resistant against Cr6?+? (83.6%) and Cr3?+? (81.8%). All isolates were categorized into Gram-positive and Gram-negative bacteria. In a total of 114 Gram-positive isolates, 91.2% were resistant to Cr6?+? followed by 73.7% to Cr3?+?, 42.1% to Zn2?+?, 40.4% to Cd2?+?, and 32.5% to Ni2?+?. Among Gram-negative isolates, 88.1% were found showing resistance to Cr6?+?, 75.0% to Cr3?+?, and 47.6% were resistant to Cd2?+?. Majority of these metal-resistant isolates were surprisingly found sensitive to the ten commonly used antibiotics. Out of 198 isolates, 114 were found sensitive to all antibiotics whereas only two isolates were resistant to maximum eight antibiotics at a time. Forty-one and 40 isolates which constitute 20.7% and 20.2% were resistant to methicilin and amoxicillin, respectively. 相似文献
Pre-harvest sprouting refers to the precocious germination of the grain in the spike prior to harvest as a result of moist
weather conditions at harvest time. From the agricultural viewpoint, it is necessary to impose an exogenous dormancy to wheat
seeds in order to improve the resistance of seed to pre-harvest sprouting. In this regard, we found that clove bud essential
oil is a strong inhibitor for wheat seed germination. The extract obtained from clove bud by supercritical fluid extraction
using CO2 as solvent minimized the number of extracts to two compounds, eugenol and eugenyl acetate. Eugenol, as the main constituent
of the oil, was responsible for its strong inhibitory activity in wheat seeds. The aqueous solution of clove bud oil was submitted
to germination assay at various concentrations from 50 to 400 mg/L. Complete inhibition of seed germination was recorded when
the concentration was 400 mg/L. Roots and sprouts have similar sensitivity to inhibitory effect. In an empirical study, the
synergistic cooperation of eugenol and eugenyl acetate from clove bud oil in the inhibition of seed germination was found
to be a 1:1 ratio. The clove bud essential oil is widely available and will broaden the horizon of applications for natural
and safe inhibitors in the fields. 相似文献
Uses of wastewater drives significant economic activity, supports countless livelihoods particularly those for developing countries. While using wastewater, the challenge is to identify practical, affordable safeguards that do not threaten the health of users. In Yanbu Al-Sinaiyah, treated sewage effluent (TSE) is used for landscape purposes. In the present study, the odour problem caused by TSE in community area has been addressed. Samples were collected and analysed for total coliform, odour, trihalomethanes (THMs), total organic carbon (TOC) and other physicochemical parameters. Results show that in distribution network, residual chlorine was below the detection limit, turbidity, THMs, TOC and total coliform concentration was much higher than point source, and concentration of these parameters was further increased in problematic areas. It was also observed that areas with odourous problem were at the tail of irrigation network. This indicates that odour problem was due to less residual chlorine high turbidity, high rate of coliform and TOC. In odourous water samples, carbon disulphide and dimethyl sulphide were also identified by GC/MS, while in other areas where there was no odour, both these compounds were not detected. Odour problem was successfully resolved by improving sand filtration system to minimise turbidity the main cause of odour, increasing the residual chlorine at the treatment plant and regularly flushing the distribution network. 相似文献
Environmental Chemistry Letters - Biodiesel is a sustainable alternative to petroleum diesel. The main bottlenecks in the commercialization of biodiesel are production costs and suitable industrial... 相似文献
Environmental Chemistry Letters - The application of natural biopolymers such as polysaccharides for the fabrication of bio-based membranes has recently attracted attention for CO2... 相似文献
A rapid process of industrialization, on the one hand, transformed the economies from agrarian to industrial societies to improve the living standards and welfare of people. On the other hand, the urbanized and industrialized economies have posed challenging threats to environmental sustainability. The query at hand is whether the growing environmental emissions are driven by industrialization and urbanization or not. This research aims to empirically examine the combined role of industrialization and urbanization in achieving carbon neutrality in Pakistan by considering foreign direct investment and economic growth as control variables in the model. The core empirical results are the following: firstly, industrialization and economic growth exhibit negative but statistically insignificant impacts on CO2 emissions, imparting a neutral role in determining the environmental degradation in Pakistan. Secondly, urbanization and foreign direct investment disclose positive and statistically significant (at 1% level of significance) impacts on CO2 emissions, manifesting an environmental degradation driving impact in the country. Thirdly, given the slope coefficients of urbanization and foreign direct investment (0.058 and 0.035), urbanization proved to be a stronger driver than foreign direct investment. Finally, foreign direct investment is revealed to make the Pakistani economy a “Pollution Haven” for the foreign enterprises in the country. Based on empirical results, none of the variables predicted the support for carbon neutrality in Pakistan.