Surfaktan adalah salah satu bahan pencemar di dalam udara yang mampu mempengaruhi perubahan iklim global di samping memberi kesan buruk kepada kesihatan manusia. Oleh itu, kajian ini telah dijalankan untuk menentukan komposisi, ciri-ciri serta pembahagian sumber bagi surfaktan dalam aerosol atmosfera, khususnya di kawasan bandar (pusat bandaraya Kuala Lumpur) dan separa bandar (Bangi, Selangor). Sampel aerosol atmosfera telah dikumpulkan dari Ogos 2010 hingga April 2011 mengikut monsun yang berbeza di Malaysia. Pensampelan aerosol dijalankan dengan menggunakan alat pensampelan udara berisipadu tinggi (HVS), dengan kadar alir 1.13 m3 min" untuk mendapatkan sampel zarahan halus « 1.5 11m) dan zarahan kasar (> 1.5 urn). Selain itu, sampel zarahan dari ekzos diesel dan petrol serta sampel debu jalan turut dikumpul. Analisis kolorimetrik telah dijalankan untuk menentukan kepekatan surfaktan anionik sebagai sebatian aktif metilena biru (MBAS) dan surfaktan kationik sebagai sebatian aktif di.....

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Anionic surfactants are one of the pollutants derived from particulate matter (PM) and adversely afect the health of living organisms. In this study, the compositions of surfactants extracted from PM and vehicle soot collected in an urban area were investigated. A high-volume air sampler was used to collect PM sample at urban area based on coarse (>1.5 µm) and fne (..

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This study aims to determine the compositions of surfactants extracted from urban particulate matter (PM) and motor vehicle exhaust soot. A high volume air sampler (HVAS) has been used to collect PM sample at Kuala Lumpur urban area. Meanwhile, the vehicle exhaust soot was collected randomly from exhaust pipe of various types of diesel and petrol vehicles, using a soft brush during dry days. The concentration of anionic surfactants as Methylene Blue Active Substances (MBAS) was determined by the colorimetric method using UV-Vis Spectrophotometer. The presence of microorganisms as bacteria and fungi was investigated by colony count. In addition, correlation between surfactants and traffic related air pollutants, and meteorological factors were also been investigated. Results revealed that the average concentration of PM was 107.68 ± 7.91 μgm-3 while surfactants in PM was 105 ± 48.8 pmolm-3. Diesel vehicles demonstrated higher surfactant concentration in exhaust soot with av.....

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Surfactant is one of the pollutants derived from atmospheric aerosol that can adversely affect the human health and environment. This study aims to characterize the level of anionic surfactants as Methylene Blue Active Substances (MBAS) and Linear Alkylbenzene Sulphonates (LAS) extracted from atmospheric aerosol from urban (Kuala Lumpur) and suburban (Bangi) area of Malaysia. For aerosol sampling, a high volume sampler (HVAS) with a cascade impactor was used to collect atmospheric aerosol sample according to particle size (coarse mode (>1.5 �m) and fine mode ( 0.05). From this study, it can be concluded that MBAS concentrations in urban and suburban atmosphere are not fully affected by commercial LAS. Majority of MBAS may be presented from other natural activities and anthropogenic sources such as motor vehicle emission, combustion of biomass, and the earth's crust. The management of surfactants? use needs to be reconsidered to enhance a better atmosphere especially in urban and subu.....

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This research delves into the psycholinguistic profiles of proficient and struggling readers among junior secondary Tamil students in Sri Lanka, with the aim of enhancing literacy instruction and intervention. Grounded in the Simple View of Reading (SVR) Theory, the study explores distinct psycholinguistic profiles and predictive factors for reading success or challenges. The research involves 140 carefully chosen students; 70 struggling readers and 70 good readers were identified based on their performance in the national Grade 5 Scholarship exam of 2021 in Puttalam South Divisional Education. A psycholinguistic screening test (PST) aligning with the SVR framework was employed to evaluate decoding and linguistic comprehension skills. The data analysis reveals notable disparities in decoding and linguistic comprehension skills between proficient and struggling readers. Linear regression analysis yields a robust model, elucidating a substantial portion of the variance in the PST profile.....

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