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The effect of nitrogen supplementation on the efficiency of colour and COD removal by Malaysian white-rot fungi in textile dyeing effluent

Lee KK, Kassim AM, Lee HK

Water Sci Technol, 2004;50(5):73-7.
PMID: 15497832

White-rot fungi, namely Coriolus versicolor and Schizophyllum commune, were studied for the biodecolorization of textile dyeing effluent in shaker-flask experiments. The results showed that C. versicolor was able to achieve 68% color removal after 5 days of treatment while that of S. commune was 88% in 9 days. Both fungi achieved the above results in non-sterile condition with diammonium hydrogen phosphate as the nutrient supplement. On the other hand, the best COD removal of 80% was obtained with C. versicolor in 9 days in sterile effluent with yeast extract as nutrient supplement, while S. commune was able to remove 85% COD within 8 days in non-sterile textile effluent supplemented with diammonium hydrogen phosphate.

Matched MeSH terms: Color; Coloring Agents/metabolism*; Coloring Agents/chemistry
Fulltext Colour vision of workers in the plastics industry

Kaur S, Mursyid A, Ariffin AE

Journal of Occupational Safety and Health, 2004;1(1):25-30.
MyJurnal

A study was undertaken to determine the effect of polyethylene and polystyrene used in the manufacture of plastic items on colour perception. Colour vision was assessed using the Ishihara plates, panel 015 test and the Farnsworth Munsell 100-Hue test. Two factories were chosen at random. One factory (referred here as factory A) used virgin resin in pellet form (polyethylene) in the manufacturing of plastic containers to store consumer edible oil. The other factory (referred as factory B) used polystyrene to make plastic bags. A total of 39 healthy employees from factory A (mean age 26.4 :t 8.2 years) and 40 healthy employees from factory B (mean age 26.8 :t 9.6 years) were recruited in this study. A control group of 27 normal healthy subjects (mean age 27.4 :t 4.3 years) who were employees of UKM with no occupational involvement with petroleum derivatives were also recruited in this study and they performed the same colour vision tests. All subjects passed the Ishihara plates test showing that none of the subjects (employees of factory A and B, and control subjects) had a congenital red-green defect. All control subjects passed all of the colour vision tests whilst some employees of factories A and B failed the 015 and FM100 Hue tests. For employees from factory A results from the 015 test showed that 7 (17.9%) had a tritan (blue-yellow) type of defect and 1 (2.6%) had a complex type of defect. The FM 100 Hue results of factory A employees showed that 51.3% (n=20) had a complex type of defect. Total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory A had a statistically significant higher mean TES of 65.13:!: 48.31 compared to that of control subjects with a mean TES of 31.26:!: 14.93. For employees in factory B, 10 employees (25.0%) had a tritan (blue-yellow) type of defect and 2 (5.0%) had a complex type of defect. Results of the FM 100 Hue test showed that 4 employees (1.0%) had a tritan type of defect whereas 22 (55.0%) had a complex type of defect. Mean total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory B had a statistically significant higher mean TES of 71.54 :t 54.63 compared with that of control subjects with a mean TES of 31.26 :t. 14.93

The above results show that employees of the plastic factories studies are associated with a higher risk of acquiring colour vision defects as compared to normal subjects who are not engaged in the plastic manufacturing industry. This may have an implication towards the future retinal health of employees in petrod1emical-based industries.

Matched MeSH terms: Color Vision Defects; Color Perception; Color Perception Tests; Color Vision
Fulltext The Immediate Term Effect Of Chewing Commercially Available Meswak (Salvadora Persica) On Levels Of Calcium, Chloride, Phosphate And Thiocyanate In Whole Saliva.

Kaur, S., Abdul Jalil, R., Akmar, S.L.

Ann Dent, 2004;11(1):-.
MyJurnal

The objective of this study was to determine the effect of chewing commercially available meswak may have on levels of calcium, chloride, phosphate and thiocyanate in stimulated whole saliva. A total of 20 subjects participated in the investigation. They were distributed into two groups. Those in group A (10 individuals) were asked to first chew on a cotton roll (sized #1) followed by the chewing of an equivalent sized 5mm piece of commercially available meswak. Subjects in group B (10 individuals) did the same but, chewed on cotton roll (sized #2) followed by the chewing of an equivalent sized 10mm piece of commercially available meswak. After following a specified chewing protocol, samples of stimulated whole saliva were collected into a graduated tube at the end of every chewing regime. Calcium, chloride, phosphate and thiocyanate analysis were carried out using colour titration and spectrophotometer. Results from this investigation indicated that commercially available meswak chewing sticks apart from containing high amounts of calcium and chloride may possibly release phosphate and thiocyanate into whole saliva. These findings suggest that the commercially available meswak used as chewing sticks may have the potential of releasing substances into saliva that could influence the state of oral health. Further studies have to be carried out to ascertain the therapeutic benefits of chewing commercially available meswak.

Matched MeSH terms: Color
On the Significance of Topological-indices Based Non-binary Molecular Similarity Measures

Naomie Salim, Holliday J, Willett P

Sains Malaysiana, 2004;33.

This paper describes experiments to study on how well the whole range of topological indices-based non-binary similarity values represents the physicochemical similarities between compounds. Measured log P values have been compared with the log P values predicted from compounds at different range of similarities calculated based on various topological indices of the compounds. Analysis shows that the non-binary Cosine, Simpson and Pearson coefficients might give misleading results when certain compounds are compared. Similarity values involving 1% most similar compounds based on the non-binary Tanimoto or Euclidean coefficients has been found to be able to represent physicochemical similarities between the molecules compared. Therefore, for searches requiring around 1% most similar compounds, rational selection methods based on the non-binary Tanimoto or Euclidean coefficients are likely to produce better results than random selection. Similarity values involving 5% most dissimilar compounds based on the non-binary Tanimoto coefficients has also been found to be able to represent physicochemical dissimilarities between the molecules compared. Therefore, for diverse selection requiring less than 5% most dissimilar compounds, rational selection methods based on the non-binary Tanimoto coefficient is likely to produce better results than random selection. However, in both focused and diverse selection using the coefficients mentioned, as more and more compounds are selected, the selection becomes more and more like random selection in terms of physicochemical properties similarity and dissimilarity.
Kertas kerja ini membincangkan mengenai kajian untuk melihat sejauh mana nilai keserupaan bukan binari yang dihasilkan melalui perbandingan indeks topologi sebatian mampu mewakili perbezaan atau keserupaan ciri fizikal dan kimia sebatian yang dibandingkan. Di dalam kajian ini, nilai log P yang diperolehi daripada ujikaji makmal telah dibandingkan dengan nilai log P jangkaan yang diambil daripada purata log P sebatian yang mempunyai pelbagai julat nilai keserupaan tertinggi berdasarkan perbandingan indeks tolopologi kesemua sebatian di dalam pangkalan data dengan sebatian berkenaan. Analisa menunjukkan yang pengiraan keserupaan bukan binari menggunakan angkali Cosine, Simpson dan Pearson boleh memberikan nilai keserupaan yang mengelirukan apabila sesetengah jenis sebatian dibandingkan. Nilai keserupaan yang melibatkan 1% sebatian paling serupa berdasarkan angkali Tanimoto atau Euclidean didapati mampu menggambarkan keserupaan ciri fizikal dan kimia sebatian yang dibandingkan. Justeru, carian atau pemilihan berfokus bagi mendapatkan 1% sebatian paling serupa dengan sesuatu sebatian menggunakan angkali Tanimoto dan Euclidean ke atas perwakilan bukan binari sebatian dijangka berkecenderungan memberikan hasil yang lebih memuaskan berbanding dengan pemilihan rambang. Nilai keserupaan yang melibatkan 5% sebatian paling berbeza berdasarkan angkali Tanimoto juga didapati mampu menggambarkan perbezaan ciri fizikal dan kimia molekul yang dibandingkan. Ini menunjukkan yang pemilihan rasional berdasarkan angkali Tanimoto bagi memilih subset yang terdiri daripada 5% molekul paling rencam dari sebuah pangkalan data molekul yang mempunyai perwakilan bukan binari berkecenderungan untuk memberikan hasil yang lebih baik daripadapemilihan secara rambang. Walau bagaimanapun. di dalam kedua-dua pemilihan berfokus atau rencam menggunakan angkali yang dinyatakan, semakin banyak sebatian yang dipilih, hasil yang didapati semakin menyerupai pemilihan secara rawak dari segi keserupaan atau kerencaman ciri fizikal dan kimia.

Matched MeSH terms: Color
Influence of Inlet Air Temperature and Feed Flow Rate on the Physical Properties of Spray-dried Mengkudu (Morinda citrifolia) Extract

Mohamad Yusof Maskat, Lee LY

Sains Malaysiana, 2004;33.

Due to the increase in consumer interest, mengkudu (Morinda citrifolia) extract is being produced in several forms including dry powder. One of the methods that can be used to produce dry powder is spray drying. This study was done to determine the physical properties of powdered mengkudu extract produced by spray drying from different sections of the spray-dryer. Mengkudu extract at 50% (v/v) dilution was spray-dried using two levels of feed flow rate (350 mL/hr and 475 mL/hr) and inlet air temperature (170oC and 190oC). Spray dried mengkudu extract from the cyclone and colletion sections of the spray dryer was collected and analyzed for amount produced, moisture content and colour. No significant interaction between feed flow rate and inlet air temperature used was observed for all parameters measured. Inlet temperature used did not show any significant effect on amount of production. However, increasing the inlet air temperature from 170oC to 190oC did produce lower moisture content for samples from the cyclone but no significant difference for samples from the collection bottle, while lowering the degree of redness of samples from the collection bottle, while lowering the degree of brightness for samples from both cyclone and collection sections of the spray-dryer. Feed flow rate used did not produce any significant effect on all parameters measured.

Matched MeSH terms: Color
Comparison of mydriatic regimens used in screening for retinopathy of prematurity in preterm infants with dark irides

Chew C, Rahman RA, Shafie SM, Mohamad Z

J Pediatr Ophthalmol Strabismus, 2005 6 28;42(3):166-73.
PMID: 15977870

PURPOSE: To determine the mydriatic regimen that provides optimal dilation of the pupil with minimal systemic side effects for screening of retinopathy of prematurity.
METHODS: This cross-sectional, randomized, double-masked clinical trial compared cyclopentolate 1% + phenylephrine 2.5%, tropicamide 1% + phenylephrine 2.5%, and a prepared combination of cyclopentolate 0.2% with phenylephrine 1% for pupillary dilation in preterm infants with dark irides. Thirteen infants were randomized to each regimen. Outcomes measured were pupillary dilation, heart rate, blood pressure, abdominal girth, and intolerance to feeds.
RESULTS: All three mydriatic regimens provided adequate pupillary dilation at 45 minutes, with dilation sustained at 60 minutes. There was a significant increase in mean blood pressure in the cyclopentolate 1% + phenylephrine 2.5% and the tropicamide 1% + phenylephrine 2.5% groups. Although there was no significant change of abdominal girth in any of the three groups, a total of eight patients developed intolerance to feeds; four (50%) of these infants were from the cyclopentolate 1% + phenylephrine 2.5% group.
CONCLUSION: The prepared combination of cyclopentolate 0.2% + phenylephrine 1% appears to be the mydriatic of choice for preterm infants with dark irides as it provided adequate pupillary dilation with the least systemic side effects.

Matched MeSH terms: Eye Color/drug effects*
Efficacy of phototherapy for neonatal jaundice is increased by the use of low-cost white reflecting curtains

Djokomuljanto S, Quah BS, Surini Y, Noraida R, Ismail NZ, Hansen TW, et al.

Arch. Dis. Child. Fetal Neonatal Ed., 2006 Nov;91(6):F439-42.
PMID: 16877479

To determine whether the addition of low-cost reflecting curtains to a standard phototherapy unit could increase effectiveness of phototherapy for neonatal jaundice.

Matched MeSH terms: Color
Fulltext The prevalence of visual defect among commercial vehicle drivers in Selangor, Malaysia

Hoe VCW

JUMMEC, 2006;9(1):35-38.
MyJurnal

A cross-sectional survey of commercial vehicle drivers who were renewing their own licences was conducted at the Selangor Road Transport Department office in Padang Jawa between 1 February 2002 and 28 February 2002, using questionnaire and medical examination. The objective was to determine the prevalence of myopia, colour vision deficiency and visual field defect among the commercial vehicle drivers. The respondents that reported visual defect at the time of interview was compared with those detected by the author through medical examination. Out of the 223 respondents, 21 (9.4%) reported to have myopia by the questionnaire survey. Through the visual examination there were 63 (28.3%) with myopia (visual acuity worse than 6/12),six (2.6%) had a visual field defect and 14 (6.3%) had red-green colour deficiency. The visual defect detected during the study among the commercial vehicle drivers, which were missed at the time of the routine medical examination were significant. The process of the statutory medical examination should be reviewed.

Matched MeSH terms: Color Vision Defects
Fulltext Prevalence of colour vision deficiency among medical students and health personnel.

Balasundaram R, Reddy SC

Malays Fam Physician, 2006;1(2):52-53.
PMID: 27570586 MyJurnal

A survey of colour vision deficiency among 1427 medical students and healthcare personnel in Seremban revealed a prevalence of 3.2% with a marked male predominance (males 6.7%, females 0.4%). In view of the potential difficulties faced by such personnel in clinical works, early detection of this deficiency allowed appropriate counselling.

Matched MeSH terms: Color Vision Defects
Fulltext Genes and genealogy of the guppy fish, Poecilia reticulata

Khoo, Gideon, Lim, Tit Meng, Phang, Violet Pan Eng

Buletin Persatuan Genetik Malaysia, 2006;12(1):5-7.
MyJurnal

Since the early 1950’s, Singapore is internationally known as the guppy-breeding centre. At least 40 different colour varieties of guppies are cultured in Singapore, with each farm specialising in 10 to 15 varieties. These fancy varieties have been developed by skilful farmers through intensive and continual selective breeding. Genes controlling background body pigmentation such as albino (a), blond (b), gold (g) and blue (r) are autosomally inherited and recessive to their wild-type alleles which produce drab olive-brown background coloration. Colour patterns which are superimposed onto wild-type background coloration are due to genes located on the sex chromosomes. These
sex-linked colour genes are dominant and sex-limited to males as their expression requires male hormones. Y-linked colour pattern genes carried by males are inherited only along the paternal line while X-linked genes are present in both sexes. Among the guppy varieties produced locally, only two Y-linked genes, Ssb and Sst, that control snakeskin tail and body patterns, respectively, have been found in varieties with snakeskin-like reticulations. Single colour genes that are both X- and Y-linked produce red (Rdt), blue (Blt), green (Grt), black (Bt) and variegated (Var) patterns
on the caudal fin. The black caudal-peduncle of the Tuxedo variety is the result of Bcp, a gene that is both X- and Ylinked. Different combinations of colour pattern genes and background pigmentation genes as well as interactions among them give rise to various colour phenotypes. For
instance, the inclusion of Bcp in Snakeskin varieties causes black reticulations on the tail fin to be replaced by large, coarse black spots. Neon coloration is produced by interactions between the Ln (light turquoise) gene with Blt, Rdt and Bcp.

Matched MeSH terms: Color
Colour removal from landfill leachate by coagulation and flocculation processes

Aziz HA, Alias S, Adlan MN, Faridah, Asaari AH, Zahari MS

Bioresour Technol, 2007 Jan;98(1):218-20.
PMID: 16386895

A study was conducted to investigate the efficiency of coagulation and flocculation processes for removing colour from a semi-aerobic landfill leachate from one of the landfill sites in Malaysia. Four types of coagulant namely aluminium (III) sulphate (alum), ferric (III) chloride, ferrous (II) sulphate and ferric (III) sulphate were studied using standard jar test apparatus. Results indicated that ferric chloride was superior to the other coagulants and removed 94% of colour at an optimum dose of 800 mg/l at pH 4. The effect of coagulant dosages on colour removal showed similar trend as for COD, turbidity and suspended solids. This suggested that colour in landfill leachate was mainly contributed by organic matters with some insoluble forms that exhibited turbidity and suspended solids readings. The results from this study suggested that ferric chloride could be a viable coagulant in managing colour problems associated with landfill leachate.

Matched MeSH terms: Color
Antenatal diagnosis of placenta previa accreta in patients with previous cesarean scar

Japaraj RP, Mimin TS, Mukudan K

J Obstet Gynaecol Res, 2007 Aug;33(4):431-7.
PMID: 17688608

To determine the accuracy of transabdominal and transvaginal gray-scale and color Doppler in diagnosing placenta previa accreta in patients with previous cesarean sections.

Matched MeSH terms: Ultrasonography, Doppler, Color/methods*
The use of alum, ferric chloride and ferrous sulphate as coagulants in removing suspended solids, colour and COD from semi-aerobic landfill leachate at controlled pH

Aziz HA, Alias S, Assari F, Adlan MN

Waste Manag Res, 2007 Dec;25(6):556-65.
PMID: 18229750

Suspended solids, colour and chemical oxygen demand (COD) are among the main pollutants in landfill leachate. Application of physical or biological processes alone is normally not sufficient to remove these constituents, especially for leachate with a lower biochemical oxygen demand (BOD)/ COD ratio. The main objective of this research was to investigate the efficiency of coagulation and flocculation processes for removing suspended solids, colour and COD from leachate produced in a semi-aerobic landfill in Penang, Malaysia. A 12-month characterization study of the leachate indicated that it had a mean annual BOD/COD ratio of 0.15 and was partially stabilized, with little further biological degradation likely to occur. Particle size analysis of the raw leachate indicated that its 50th percentile (d50) was 11.68 microm. Three types of coagulants were examined in bench scale jar test studies: aluminium sulphate (alum), ferric chloride (FeCl3) and ferrous sulphate (FeSO4). The effects of agitation speed, settling time, pH, coagulant dosages and temperature were examined. At 300 rpm of rapid mixing, 50 rpm of slow mixing, and 60 min settling time, higher removals of suspended solids (over 95%), colour (90%) and COD (43%) were achieved at pH 4 and 12. FeCl3 was found to be superior to other coagulants tested. At pH 4 and 12, fair removal of suspended solids was observed at a reasonably low coagulant dose, i.e., 600 mg L(-1); hHowever, about 2500 mg L(-1) of coagulant was required to achieve good removals at pH 6. Better removals were achieved at higher temperature. The d50 of sludge after coagulation at pH 4 with a 2500 mg L(-1) FeCl3 dose was 60.16 microm, which indicated that the particles had been removed effectively from the leachate. The results indicate that coagulation and flocculation processes can be used effectively in integrated semi-aerobic leachate treatment systems, especially for removing suspended solids, colour and COD.

Matched MeSH terms: Color
Investigating data entry task performance on a laptop under the impact of vibration: the effect of color

Mallick Z

Int J Occup Saf Ergon, 2007;13(3):291-303.
PMID: 17888238

The last 20 years have seen a tremendous growth in mobile computing and wireless communications and services. An experimental study was conducted to explore the effect of text/background color on a laptop computing system along with variable environmental vibration on operators' data entry task performance in moving automobiles. The operators' performance was measured in terms of the number of characters entered per minute without spaces (NCEPMWS) on a laptop computing system. The subjects were divided into 3 categories, namely, Novices, Intermediates and Experts. Findings suggest a re-evaluation of existing laptop designs taking ergonomics into consideration. It appears that proper selection of text/background color on the laptop coupled with controlled vehicular speed could result in a better quality of interaction between human and laptops and it could also resolve the problem of poor data entry task performance.

Matched MeSH terms: Color
Fulltext Infantile Myofibromatosis: A Case Report

Hasniah, A.L., Rohana, J., Boo, N.Y., Thambidorai, C.R., Isa, M.R.

International Medical Journal Malaysia, 2007;6(1):1-6.
MyJurnal

Case: A male infant was born at 36th week period of gestation with a birth weight of 1.99kg following an uneventful intrauterine period. At birth, he was noted to have multiple skin nodules. The largest nodule measuring 4.0 x 2.0 x 1.5 cm was at his pre-auricular area. It was initially fleshy and reddish in color. A few days later, it turned black and subsequently the black skin overlying the mass fell off, leaving a firm underlying mass with the appearance of a cauliflower. Other skin lesions, which were firm in consistency, were found on the medial aspect of his right supraorbital ridge, right mid-arm, right mid-thigh, plantar surface of his right big toe and his scalp. They were either skin-colored or reddish in colour, measuring between 1.0 and 2.0 cm in diameter. He also had hepatomegaly and splenomegaly palpable at 5 cm and 3 cm below the subcostal margins, respectively

Matched MeSH terms: Color
Fulltext Global colour scale for tmeline events in ion dynamics

Sharif, J.M., Latiff, M.S.A., Ngadi, M.A.

ASM Science Journal, 2007;1(2):109-128.
MyJurnal

Spatio-temporal datasets are a collection of datasets where data can vary in both space and time. Theoretically, such datasets can be considered as continuous and discrete. For example, specification of the function, F: Ed  T Rn, where Ed denotes d-dimensional Euclidean space, T = R* ∩ {} the domain of time and Rn an n-dimensional scalar field. Examples of such data sets include time-varying simulation results, film and videos, time-varying medical datasets, geometry models with motion or deformation, meteorological measurements, and many more. It is therefore highly desirable to use visualisation to summarize meaningful information in higher dimensional spatio-temporal datasets. Our aim is to conceive an efficient visual study to facilitate scientists in identifying temporal association among complex and chaotic atom movements in ion trajectories. An application that uses a streamline for spatial motion of ion trajectories and Colour Number Coding Scheme for temporal encoding of high degree of timeline events among mobile ions is proposed. With an anthology of the visual examples, it was revealed that this application would be beneficial for scientists to visually mine any 3D spatio-temporal dataset.

Matched MeSH terms: Color
Fulltext Optical tomography: real time image reconstruction for various flow regimes in gravity flow conveyor

Abdul Rahim, R., Pang, J.F., Chan, K.S., Leong, L.C., Fazalul Rahiman, M.H.

ASM Science Journal, 2007;1(1):27-36.
MyJurnal

In this study, real-time imaging was monitored for flowing solid particles when various baffles were created to block certain areas of the pipe. The generated flow regimes were full-flow, three-quarter-flow, half-flow and quarter-flow. A vertical pneumatic conveyor was designed to hold a 85 mm inner diameter pipeline. The four projection optical tomography systems used, applied the parallel beam projection approach and use infrared light sources so that the sensor was free of noise from the surrounding visible light source. The two orthogonal and two rectilinear projections were axial, but ideally they should have been in the same layer. The sensor readings could be related to the varying light intensity effects of the dropping particles and were used to provide cross-sectional distribution information for the conveyor. By using computer programming, the information was reconstructed to produce coloured images and concentration was obtained by reference to a colour code. The results obtained from this study showed how imaged flow followed the artificial flow regime. This study could benefit industrial production lines in maintaining the desired flow rates.

Matched MeSH terms: Color
Pengujian kesesuaian taburan normal berdasarkan statistik Cramer-von Mises

Ani Shabri, Abdul Aziz Jemain

Sains Malaysiana, 2007;36:201-206.

Sejak taburan normal ditemui dan ianya merupakan salah satu taburan yang penting dalam statistik, terdapat banyak pengujian statistik yang dibangunkan untuk menguji kenormalan data. Namun begitu masih tidak banyak kajian yang dilakukan untuk melihat kembali keupayaan pengujian statistik yang sedia ada. Sebahagian daripada pengujian statistik didapati mudah tetapi hanya sesuai untuk sesuatu keadaan. Dalam kajian ini, pengujian statistik berdasarkan statistik Cramer-von Mises cuba diperbaiki berdasarkan rumus Weibull. Kekuatan statistik yang baru ini dibandingkan kekuatan dengan statistik traditional Anderson-Darling (AD), Cramer von-Mises (CR), Kolmogorov-Smirnov (KS) dan Shapiro-Wilk (SW). Kajian simulasi berdasarkan beberapa taburan yang berbeza menunjukkan pengujian statistik yang dicadangkan paling sesuai untuk menguji kenormalan.

Matched MeSH terms: Color
Perubahan nisbah 234U/238U dalam pepejal terampai di Kuala Selangor, Selangor, Malaysia

Khairul Nizam Mohd Ramli, Che Abd. Rahim Mohamed, Zaharuddin Ahmad

Sains Malaysiana, 2007;36:9-13.

Kajian ini dijalankan bagi mengenalpasti kepelbagaian nisbah 234U/238U yang wujud di dalam jumlah pepejal terampai (TSS) pada lapan stesen yang berbeza di Kuala Selangor, Selangor. Prosedur kajian ini melibatkan proses persampelan, pemendakan, resin penukaran anion, pemendakan elektrik dan teknik pengiraaan spektrometer alfa. Nisbah 234U/238U adalah paling tinggi di Stesen 8 (234U/238U = 2.98) dan Stesen 2 (234U/238U = 3.34) pada persampelan pertama. Manakala pada persampelan kedua julat nisbah 234U/238U adalah lebih luas iaitu antara 1.29 (Stesen 4) hingga 11.57 (Stesen 6). Ini disebabkan oleh berlakunya pergerakan 234U bersama-sama mikroorganisme di dalam fasa terampai dan berlaku proses penurunan U(VI) kepada U(IV) yang akan memendakkan uranium daripada air ke dalam sedimen.

Matched MeSH terms: Color
Pengambilan Fe, Mn dan Cu oleh Nepenthes sp. dalam tanih bekas lombong Pelepah Kanan Kota Tinggi, Johor

Sahibin Abd. Rahim, Tukimat Lihan, Zulfahmi Ali Rahman, Wan Mohd. Razi Idris, Azman Hashim, Sharilnizam M. Yusof, et al.

Sains Malaysiana, 2007;36:9-13.

Kandungan logam berat Fe, Cu dan Mn dalam tanih serta tumbuhan Nepenthes sp yang diambil daripada kawasan bekas lombong bijih timah dan besi di Lombong Pelepah Kanan, Kota Tinggi, Johor telah dikaji. Kandungan logam berat telah ditentukan di dalam empat bahagian tumbuhan Nepenthes sp. iaitu di dalam akar, batang, daun dan periuk. Sebanyak 15 sampel tumbuhan Nepenthes sp dan tanih dikumpul untuk dianalisis. Komposisi logam-logam berat dalam sampel tanih diekstrak dengan menggunakan campuran asid nitrik dan asid perklorik. Kandungan logam berat dalam tumbuhan pula diekstrak melalui kaedah penghadaman basah. Kandungan logam berat di dalam larutan ekstrak tanih dan tumbuhan ditentukan dengan menggunakan alat Spektrofotometer Serapan Atom Kaedah Nyalaan (FAAS). Nilai Koefisien Penyerapan Biologi (BAC) dikira sebagai nisbah kandungan logam berat dalam tumbuhan kepada kandungan logam berat dalam tanih. Analisis tanih menunjukkan kawasan bekas lombong didominasi oleh pasir dan bersifat asid. Ia juga mempunyai kandungan bahan organik dan nilai kekonduksian elektrik yang rendah. Logam Fe mencatatkan kepekatan purata paling tinggi di dalam tanih diikuti oleh Mn dan Cu. Tumbuhan Nepenthes sp boleh dijadikan sebagai pengumpul biologi untuk logam Fe kerana nilai BACnya adalah tinggi.

Matched MeSH terms: Color

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