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1.
This paper shows that spent lubricating oils from automobile engines generate carboxylic acids on environmental exposure. Samples of exposed oils, isolated from polluted river water and shore muds obtained from various locations, showed a direct proportionality between carboxylic acid content and time of exposure. Carboxylic acids were isolated by solvent extraction and studied by infrared spectroscopy. 相似文献
2.
Jumin Ellysia Basaruddin Faridah Bte Yusoff Yuzainee Bte. Md Latif Sarmad Dashti Ahmed Ali Najah 《Environmental science and pollution research international》2021,28(21):26571-26583
Environmental Science and Pollution Research - Reliable and accurate prediction model capturing the changes in solar radiation is essential in the power generation and renewable carbon-free energy... 相似文献
3.
Mohd Talib Latif Sofia Aida Ngah Doreena Dominick Intan Suraya Razak Xinxin Guo Thunwadee Srithawirat Idris Mushrifah 《环境科学学报(英文版)》2015,27(7):143-155
The aim of this study was to determine the source apportionment of dust fall around Lake Chini, Malaysia. Samples were collected monthly between December 2012 and March2013 at seven sampling stations located around Lake Chini. The samples were filtered to separate the dissolved and undissolved solids. The ionic compositions(NO-3, SO2-4, Cl-and NH+4) were determined using ion chromatography(IC) while major elements(K, Na, Ca and Mg) and trace metals(Zn, Fe, Al, Ni, Mn, Cr, Pb and Cd) were determined using inductively coupled plasma mass spectrometry(ICP-MS). The results showed that the average concentration of total solids around Lake Chini was 93.49 ± 16.16 mg/(m2·day). SO2-4, Na and Zn dominated the dissolved portion of the dust fall. The enrichment factors(EF) revealed that the source of the trace metals and major elements in the rain water was anthropogenic, except for Fe. Hierarchical agglomerative cluster analysis(HACA) classified the seven monitoring stations and 16 variables into five groups and three groups respectively. A coupled receptor model, principal component analysis multiple linear regression(PCA-MLR), revealed that the sources of dust fall in Lake Chini were dominated by agricultural and biomass burning(42%),followed by the earth's crust(28%), sea spray(16%) and a mixture of soil dust and vehicle emissions(14%). 相似文献
4.
Liew Juneng Mohd Talib Latif Fredolin T. Tangang Haslina Mansor 《Atmospheric environment (Oxford, England : 1994)》2009,43(30):4584-4594
The recurrence of forest fires in Southeast Asia and associated biomass burning, has contributed markedly to the problem of trans-boundary haze and the long-range movement of pollutants in the region. Air pollutants, specifically particulate matter in the atmosphere, have received extensive attention, mainly because of their adverse effect on people's health. In this study, the spatial and temporal variability of the PM10 concentration across Malaysia was analyzed by means of the rotated principal component analysis. The results suggest that the variability of the PM10 concentration can be decomposed into four dominant modes, each characterizing different spatial and temporal variations. The first mode characterizes the southwest coastal region of the Malaysian Peninsular with the PM10 showing a peak concentration during the summer monsoon i.e. when the winds are predominantly southerlies or southwesterlies, and a minimal concentration during the winter monsoon. The second mode features the region of western Borneo with the PM10 exhibiting a concentration surge in August–September, which is likely to be the result of the northward shift of the Inter Tropical Convergence Zone (ITCZ) and the subsequent rapid arrival of the rainy season. The third mode delineates the northern region of the Malaysian Peninsular with strong bimodality in the PM10 concentration. Seasonally, this component exhibits two concentration maxima during the late winter and summer monsoons, as well as two minima during the inter-monsoon periods. The fourth dominant mode characterizes the northern Borneo region which exhibits weaker seasonality of the PM10 concentration. Generally, the seasonal fluctuation of the PM10 concentration is largely associated with the seasonal variation of rainfall in the country. However, in addition to this, the PM10 concentration also fluctuates markedly in two timescale bands i.e. 10–20 days quasi-biweekly (QBW) and 30–60 days lower frequency (LF) band of the intra-seasonal timescales. These intra-seasonal fluctuations show strong seasonality with the largest fraction of variance occurring during the boreal summer and the weakest variance during the winter. Generally, the LF intra-seasonal oscillation is stronger compared to the QBW intra-seasonal band. 相似文献
5.
Parsaie Abbas Haghiabi Amir Hamzeh Latif Sarmad Dashti Tripathi Ravi Prakash 《Environmental science and pollution research international》2021,28(43):60842-60856
Environmental Science and Pollution Research - Predictions of pore pressure and seepage discharge are the most important parameters in the design of earth dams and assessing their safety during the... 相似文献
6.
Md. Firoz Khan Mohd Talib Latif Liew Juneng Norhaniza Amil Mohd Shahrul Mohd Nadzir Hossain Mohammed Syedul Hoque 《Journal of the Air & Waste Management Association (1995)》2013,63(8):958-969
Long-term measurements (2004–2011) of PM10 (particulate matter with an aerodynamic diameter <10 μm) and trace gases (carbon monoxide [CO], ozone [O3], nitrogen oxide [NO], oxides of nitrogen [NOx], nitrogen dioxide [NO2], sulfur dioxide [SO2], methane [CH4], nonmethane hydrocarbon [NMHC]) have been conducted to study the effect of physicochemical factors on the PM10 concentration. In addition, this study includes source apportionment of PM10 in Kuala Lumpur urban environment. An advanced principal component analysis (PCA) technique coupled with absolute principal component scores (APCS) and multiple linear regression (MLR) has been applied. The average annual concentration of PM10 for 8 yr is 51.3 ± 25.8 μg m?3, which exceeds the Recommended Malaysian Air Quality Guideline (RMAQG) and international guideline values. Detail analysis shows the dependency of PM10 on the linear changes of the motor vehicles in use and the amount of biomass burning, particularly from Sumatra, Indonesia, during southwesterly monsoon. The main sources of PM10 identified by PCA-APCS-MLR are traffic combustion (28%), ozone coupled with meteorological factors (20%), and windblown particles (1%). However, the apportionment procedure left 28.0 μg m?3, that is, 51% of PM10 undetermined.Implications: Air quality is always a top concern around the globe. Especially in the South Asian regions, measures are not yet sufficient; as revealed in our studies, the concentrations of particulate matters exceed the tolerable limits. Long-term data analysis and characterization of particular matters and their sources will aid the policy makers and the concerned authority to adapt measures and policies according to the circumstances. Additionally, similar intensive studies will give insight about future implications of air quality management. 相似文献
7.
A solid phase extraction method for the determination of gold(III) at trace levels by flame atomic absorption spectrometer
(FAAS) was developed. The method was based on retention of gold as chloro complexes through the Amberlite XAD-2000. The effect
of some analytical parameters including hydrochloric acid concentration, sample volume, sample and eluent flow rates, eluent
volume, eluent concentration and interfering ions on the recovery of gold(III) was investigated. The retention of gold(III)
from 1.5 mol l−1 HCl solution and the recovery of gold with 0.07 mol l−1 NH3 solution were quantitative (≥95%). The relative standard deviation (RSD) was calculated as 3.2% (n = 10). The detection limit for gold was 2 μg l−1. The accuracy was checked with the determination of gold spiked an artificial seawater and a pure copper samples. 相似文献
8.
During the 1980s Ethiopia experienced the effects of conflict, drought and famine on a scale far greater than many CPEs elsewhere. In May 1991, after the decisive defeat of the military dictatorship of Mengistu Haile Mariam by the Ethiopian Peoples' Revolutionary Democratic Front (EPRDF) and after decades of civil war, drought and famine, Ethiopia faced the prospects of peace and of much needed development. This paper explores both Ethiopia's experience of conflict and humanitarian intervention in areas of Tigray held by the Tigray Peoples' Liberation Front (TPLF) during the 1980s, and its experience of post-conflict rehabilitation and reconstruction in the 1990s. It first deals with the roots of the conflicts within Ethiopia: political marginalisation, heavy state intervention and highly extractive relations between state and peasants, inappropriate and failed development policies, ethnic identity and the politicisation of ethnicity. The Mengistu regime's counter-insurgency measures are then contrasted with the policies and programmes of the TPLF, Ethiopia's most effective opposition movement and the leading element in the EPRDF, and its achievements in mobilising popular support: its establishment of democratically elected structures of local governance and its famine relief distribution programme. 相似文献
9.
This paper reports the utilization of 4-(2-pyridylazo) resorcinol (PAR) as a chelating reagent for in-column derivatization
and the determination of trace Co, Fe, and Ni ions by reversed-phase high-performance liquid chromatography with photodiode
array detector. A good separation of Co, Fe, and Ni chelates were achieved by using an Inertsil ODS-3 column and a mobile
phase, consisted of methanol–THF–water mixture (50:5:45) containing ammonium acetate buffer (pH 5.0) and PAR. After full optimization,
good repeatability of retention times (relative standard deviation (RSD) < 0.05%) and peak areas (RSD < 1.7%) was achieved
as well as a good linearity (r
2 > 0.9991). The detection limits (S/N = 3), expressed as micrograms per liter, were 0.50 (Co), 9.07 (Fe), and 2.00 (Ni). The applicability and the accuracy of
the developed method were estimated by the analysis of spiked water samples and certified reference material BCR 715 wastewater-SRM. 相似文献
10.
Latif Aref Amir H. Navarchian Daniyal Dadkhah 《Journal of Polymers and the Environment》2017,25(3):628-639
Poly(acrylamide-co-maleic acid)/montmorillonite nanocomposites, were synthesized via in situ polymerization with different maleic acid and MMT content. The capability of the hydrogel for adsorption of crystal violet (CV) was investigated in aqueous solutions at different pH values and temperatures. The pseudo-second-order kinetics model could fit successfully the adsorption kinetic data. The effects of maleic acid to acrylamide molar ratio (MAR), weight percent of MMT (MMT%), the pH of medium and the solution temperature (T) on the CV adsorption capacity (q e ) of adsorbents were studied by Taguchi experimental design approach. The results indicated that increasing the MMT% leads to a greater q e . The q e value of adsorbents increased also with increasing both MAR and pH, while reduced when the temperature of medium increased. The relatively optimum conditions to achieve a maximum CV adsorption capacity for P(AAm/MA)/MMT adsorbents were found as: 0.06 for MAR and 5 % of MMT%, medium pH = 7 and T = 20 °C. 相似文献