Environmental Science and Pollution Research - Scarcity in mining and geo-political direction diverts attention toward critical metal recycling. Gallium (Ga), indium (In) and germanium (Ge) are... 相似文献
Trichloroethene (TCE) degradation by Fe(III)-activated calcium peroxide (CP) in the presence of citric acid (CA) in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concentration of soluble Fe(III) and promoting H2O2 generation. The generation of HO? and O2-? in both the CP/Fe(III) and CP/Fe(III)/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO?, while O2-? strengthened the generation of HO? by promoting Fe(III) transformation in the CP/Fe(III)/CA system. Acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl-, HCO3-, and humic acid (HA) inhibited TCE degradation to different extents for the CP/Fe(III)/CA system. Analysis of Cl- production suggested that TCE degradation in the CP/Fe(III)/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe(III)-activated calcium peroxide for treating TCE contaminated groundwater. 相似文献
Journal of Polymers and the Environment - The alkali-soluble cell wall polysaccharides (CWPs), extracted from Nelumbo nucifera rhizome flour (NNRF), were treated with microwave radiation to modify... 相似文献
Environmental Science and Pollution Research - Economic growth in modern-day world get attention primarily through innovation and higher productivity, which places technology and knowledge at the... 相似文献
Pakistan is an agricultural country and due to the shortage of clean water, most of the irrigated area (32,500 ha) of Pakistan was supplied with wastewater (0.876?×?109 m3/year). Concentrations of heavy metals in radish (Raphanus sativus) and turnip (Brassica rapa) taken from vegetable fields in Sargodha, Pakistan, were measured. Untreated wastewater was used persistently for a long time to irrigate these vegetable fields. A control site was selected that had a history of fresh groundwater irrigation. Mean metal concentrations were found for irrigation water, soil, and vegetables. In irrigation water, concentrations of Mo and Pb at three sites and Se at sites II and III were higher than the recommended limits. In vegetables, concentrations of Mo and Pb were above the maximum permissible limits. High bioconcentration factor was observed for Zn (12.61 in R. sativus and 11.72 in B. rapa) at site I and high pollution load index was found for Pb (3.89 in R. sativus and 3.87 in B. rapa) at site II. The differences in metal concentrations found in samples depended upon different soil nature and assimilation capacities of vegetables at different sites which in turn depended upon different environmental cues. The entrance of metal and metalloids to human body may happen through different pathways; however, the food chain is the chief route through which metals are transferred from vegetables to individuals. Health risk index observed for metals, (Mo, As, Ni, Cu, and Pb) higher than 1 indicated high risk through consumption of these vegetables at three sites.
Environmental and Ecological Statistics - The paper proposes a new perspective in the environmental and resource economics literature by examining innovation (measured by R&D expenditures),... 相似文献
Environmental Science and Pollution Research - Heavy metals (HMs) being the notorious and toxic are being introduced into the environment credited to natural and anthropogenic activities. The use... 相似文献
Environmental Science and Pollution Research - In this study, Moringa seed powder (MSP) was pyrolyzed at 450 °C to synthesize Moringa seed powder biochar (MSPB) and treated with phosphoric... 相似文献
Hair and nail samples from young Pakistani adults were separately analyzed for quantification of Cd, Cr, Cu, Ni, Pb, and Zn concentrations. The concentrations of these metals were also analyzed in commonly consumed local foods to evaluate potential correlation of hair and nail concentrations with diet. Pearson correlation coefficients ranged from 0.349 to 0.999, demonstrating diet to be a significant contributor for accumulation of heavy metals in humans. 相似文献
Environmental impact assessment (EIA) is a policy tool used for evaluating a project proposal from physical and socioeconomic
environmental perspectives. Its aim is to reduce the impact of development on environment, hence, ensuring environmental sustainability.
It is mandatory to submit an Environmental Impact Statement before starting a mega project as required by Environmental Protection
Act of 1997 and Environmental Policy of Pakistan. Public consultation plays a key role in an EIA system, identifying the likely
aspects and impacts of a development activity. This aspect has been ignored in effective enactment of environmental legislation
in Pakistan. Sufficient legislative instruments are there to support EIA system in the country but the agencies responsible
for the enforcement of environmental regulations have failed to do so. The current research gives an insight into the actual
status of EIA system in Pakistan along with the feedback of EIA specialists and university teachers of the concerned departments.
A new index has been devised on the basis of questionnaire response to work out the overall performance of EIA system in Pakistan
or any other country. The weaknesses and deficiencies of each EIA stage have been worked out for Pakistan and elaborated with
the help of the controversial Zero point Interchange Project in the capital city of Pakistan. 相似文献