排序方式: 共有9条查询结果,搜索用时 203 毫秒
1
1.
<正>The power and efficiency of gasoline engines is often improved through the use of fuel with high octane ratings.The octane rating of fuel could be further increased with oxygenate additives such as alcohols and ethers, with methyl tert-butyl ether (MTBE) being one of the most common gasoline additives. The Agency for Toxic Substances and Disease 相似文献
2.
Beniaich Ghada Salim Rajae Ech-chihbi Elhachmia El-Hajjaji Fadoua Rais Zakia Abdellaoui Abdelfattah Taleb Mustapha 《Environmental science and pollution research international》2022,29(1):133-145
Environmental Science and Pollution Research - An ethnobotanical survey was conducted among herbalists in the north-central region of Morocco using a questionnaire in order to highlight knowledge... 相似文献
3.
Both the bioavailability of a trace metal (TM) in a soil and the risk of leaching to the ground water are linked to the metals concentration in the soil solution. Sampling soil solution by tension lysimetry with suction cups is a simple and established technique that is increasingly used for monitoring dissolved TM in soils. Of major concern, however, is the sorption of TM by the walls of the samplers. Metal sorption by different materials used in suction cups can vary widely, depending also on the chemistry of the soil solution. We compared the sorption of Cu, Zn, Cd, and Pb by different standard-size and micro suction cups in the laboratory at two pH values (4.5 and 7.5 or 8.0) in absence and presence of dissolved organic carbon (DOC). In addition, we investigated the sorption of DOC from different origins by the cup materials. At both pH values, the weakest sorption of all four TMs was exhibited by standard-size suction cups based on nylon membranes and by hollow fibers made from polyvinyl alcohol (PVA). At alkaline pH, borosilicate glass, ceramic materials, and polytetrafluorethylene (PTFE) mixed with silicate were characterized by generally strong sorption of all investigated TMs. In addition, Cu and Pb were strongly sorbed at low pH by PTFE-silicate and a ceramic material used for the construction of standard-size suction cups. On the other hand, sorption of Cu, Zn, and Cd by ceramic capillaries produced from pure aluminum oxide was negligible at low pH. Micro suction cups made of an unknown polymerous tube sorbed Cu strongly, but were well suited to monitor Zn, Cd, and Pb at low pH, and, in the presence of DOC, also at high pH. Major cations (Na+, Mg2+, K+, Ca2+) and anions (Cl-, NO3-, SO4(2-)) were not or very weakly sorbed by all cup materials, except for Mg2+, K+, and Ca2+ by borosilicate glass at pH 7.5. Trace metal sorption by suction cups was generally greatly reduced in the presence of DOC, especially at alkaline pH. The sorption of DOC itself depended on its source. Dissolved organic carbon from leaf litter extracts with a probably large hydrophobic fraction was sorbed more strongly than mainly hydrophilic DOC from a mineral soil solution. 相似文献
4.
Shahzad Tahir Shah Syed Tahir Hussain Rais Syed Imran Mansoor Abdul Zaman Khalid 《Environmental science and pollution research international》2022,29(35):52635-52654
Environmental Science and Pollution Research - Recent environmental research has found that people with higher incomes and in more developed countries are more willing to pay (WTP) to protect their... 相似文献
5.
Hassan Iftekhar Husain Fohad Mabood Khan Rais Ahmad Ebaid Hossam Al-Tamimi Jameel Alhazza Ibrahim M. Aman Shazia Ibrahim Khalid Elfaki 《Environmental science and pollution research international》2019,26(10):9966-9980
Environmental Science and Pollution Research - Potassium bromate (PB) is a commonly used food additive, a prominent water disinfection by-product, and a class IIB carcinogen. It exerts a various... 相似文献
6.
Rais Ahmad Rajeev Kumar Mohammad Asaduddin Laskar 《Environmental science and pollution research international》2013,20(1):219-226
Background
The adsorption characteristics of Pb2+ ions from aqueous solutions onto calix[4]naphthalene have been investigated.Method
Calix[4]naphthalene was prepared by the condensation of 1-naphthol and formaldehyde (1:2) in presence of hydrochloric acid at 80°C. The effect of various operation parameters, such as solution pH, initial metal ion concentration, contact time, and temperature, on the adsorption capacity of calix[4]naphthalene for Pb2+ have been investigated.Result
Experimental results showed that the adsorption of Pb2+ ions increased with the increase in solution pH and temperature. Langmuir and Freundlich isotherms models were used to describe the adsorption behavior of Pb2+ by calix[4]naphthalene. Equilibrium data fitted well with the Langmuir isotherm model and the maximum adsorption capacity of calix[4]naphthalene for Pb2+ at 30°C was found to be 29.15 mg g?1. Kinetic studies indicated that the adsorption followed pseudo-second order model and the thermodynamic studies revealed that the adsorption process was spontaneous and endothermic in nature. The obtained results demonstrated that calix[4]naphthalene can be used as an effective adsorbent for Pb2+ ions removal from water. 相似文献7.
Many eurythermal organisms alter composition of their membranes to counter perturbing effects of environmental temperature
variation on membrane fluidity, a process known as homeoviscous adaptation. Marine intertidal gastropods experience uniquely
large thermal excursions that challenge the functional integrity of their membranes on tidal and seasonal timescales. This
study measured and compared membrane fluidity in marine intertidal snail species under three scenarios: (1) laboratory thermal
acclimation, (2) thermal acclimatization during a hot midday low tide, and (3) thermal acclimatization across the vertical
intertidal zone gradient in temperature. For each scenario, we used fluorescence polarization of the membrane probe DPH to
measure membrane fluidity in individual samples of gill and mantle tissue. A four-week thermal acclimation of Tegula funebralis to 5, 15, and 25°C did not induce differences in membrane fluidity. Littorina keenae sampled from two thermal microhabitats at the beginning and end of a hot midday low tide exhibited no significant differences
in membrane fluidity, either as a function of time of day or as a function of thermal microhabitat, despite changes in body
temperature up to 24°C within 8 h. Membrane fluidities of a diverse group of snails collected from high, middle, and low vertical
regions of the intertidal zone varied among species but did not correlate with thermal microhabitat. Our data suggest intertidal
gastropod snails do not exhibit homeoviscous adaptation of gill and mantle membranes. We discuss possible alternatives for
how these organisms counter thermal excursions characteristic of the marine intertidal zone. 相似文献
8.
Adsorption of malachite green (MG) from aqueous solution onto treated ginger waste (TGW) was investigated by batch and column methods. The effect of various factors such as initial dye concentration, contact time, pH and temperature were studied. The maximum adsorption of MG was observed at pH 9. Langmuir and Freundlich isotherms were employed to describe the MG adsorption equilibrium. The monolayer adsorption capacities were found to be 84.03, 163.9 and 188.6 mg/g at 30, 40 and 50 °C, respectively. The values of thermodynamic parameters like ΔG°, ΔH° and ΔS° indicated that adsorption was spontaneous and endothermic in nature. The pseudo second order kinetic model fitted well in correlation to the experimental results. Rechienberg's equation was employed to determine the mechanism of adsorption. The results indicated that film diffusion was a major mode of adsorption. The breakthrough capacities were also investigated. 相似文献
9.
Bouaich Fatima Zahra Maherzi Walid El-hajjaji Fadoua Abriak Nor-Edine Benzerzour Mahfoud Taleb Mustapha Rais Zakia 《Environmental science and pollution research international》2022,29(1):146-157
Environmental Science and Pollution Research - This work concerns the reuse of treated wastewater from Er-Rachidia wastewater treatment plant (WWTP) in the mixing of ordinary C20/25 concrete, to... 相似文献
1