Displaying publications 61 - 80 of 415 in total

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  1. Jamaludin NFM, Abdullah LC, Idrus S, Engliman NS, Tan JP, Jamali NS
    Bioresour Technol, 2024 Jan;391(Pt A):129933.
    PMID: 37898370 DOI: 10.1016/j.biortech.2023.129933
    Nickel-iron doped granular activated carbon (GAC-N) was used to enhance immobilization in biohydrogen production. The effect of the sludge ratio to GAC-N, ranged 1:0.5-4, was studied. The optimum hydrogen yield (HY) of 1.64 ± 0.04 mol H2/mol sugar consumed and hydrogen production rate (HPR) of 45.67 ± 1.00 ml H2/L.h was achieved at a ratio of 1:1. Immobilization study was performed at 2 d HRT with a stable HY of 2.94 ± 0.16 mol H2/mol sugar consumed (HPR of 83.10 ± 4.61 ml H2/L.h), shorten biohydrogen production from 66 d to 26 d, incrementing HY by 57.30 %. The Monod model resulted in the optimum initial sugar, maximum specific growth rate, specific growth rate, and cell growth saturation coefficient at 20 g/L, 2.05 h-1, 1.98 h-1 and 6.96 g/L, respectively. The dominant bacteria identified was Thermoanaerobacterium spp. The GAC-N showed potential as a medium for immobilization to improve biohydrogen production.
    Matched MeSH terms: Iron
  2. Lee WS, Aziz HA, Tajarudin HA
    Water Environ Res, 2023 Aug;95(8):e10913.
    PMID: 37475142 DOI: 10.1002/wer.10913
    Groundwater is one of the alternatives to surface water that can be used for drinking water; however, it normally exists with high iron and manganese content. In this study, a column study was conducted to observe the elimination of iron (Fe) and manganese (Mn) in the groundwater under different retention times by using zeolite immobilized with iron-oxidizing bacteria (IOB). Rossellomorea sp., representing an IOB, was found from the isolation process and was further cultured in the laboratory for immobilization into the natural zeolite as replacement materials for the sand filter. When the zeolite assisted with the Rossellomorea sp. was used, the elimination of Fe and Mn were 99.34% and 88.92%, respectively, compared to the removal of Fe and Mn, which were 93.62% and 93.73%, respectively, for media without immobilization. The presence of Rossellomorea sp. enhances the Fe oxidation, resulting in high removal of Fe. The Thomas and Yoon-Nelson models were performed in both raw zeolite and zeolite with IOB. The total coliform (most probable number [MPN]) increased from 70.8 to 307.6 MPN/100 mL because of the Rossellomorea sp. present that promotes the growth of coliform bacteria. In conclusion, the immobilization of zeolite with IOB is a potential technique to extract the Fe and Mn in the groundwater. PRACTITIONER POINTS: Zeolite incorporated with Rossellomorea sp. has higher removal performance of Fe, whereas the removal of Mn reduced compared to the raw zeolite. The presence of Rossellomorea sp. enhances the oxidation of ferrous iron and improves the removal of Fe in the groundwater because the ferric iron is the priority ion to be exchanged. The removal of UV254 increase when Rossellomorea sp. present in the zeolite because the Rossellomorea sp. consume the natural organic matter as carbon source.
    Matched MeSH terms: Iron
  3. Pang FS, Liaw EYF, De S
    Postgrad Med J, 2023 Sep 21;99(1176):1068-1075.
    PMID: 37334974 DOI: 10.1093/postmj/qgad047
    Jehovah's Witness (JW) is a denomination of Christianity which has many-fold higher morbidity and mortality compared to the general population as they refuse blood transfusion. Information is scanty regarding guidelines on the optimal approach to pregnant ladies of JW faith. In this review we have attempted to analyse the ways and techniques available which can be used to reduce the morbidity and mortality of these women. In antenatal care, haematological status can be optimised to reduce modifiable risk factors, namely anaemia by parenteral iron therapy from the second trimester onwards especially in patients who do not respond to oral iron therapy. In severe cases, erythropoietin serves as an effective alternative to blood transfusion. During the intrapartum period, using antifibrinolytics, cell salvage, bloodless surgical techniques, and uterine cooling for patients undergoing caesarean delivery have been proven effective. To conclude, complications of pregnant JW patients may be reduced if they comply with the preventives and targeted monitoring during the various phases of pregnancy. Further studies are warranted as this population exists as a minor group but is growing worldwide.
    Matched MeSH terms: Iron
  4. Al-Mekhlafi HM, Al-Zabedi EM, Al-Maktari MT, Atroosh WM, Al-Delaimy AK, Moktar N, et al.
    Nutrients, 2014 Jan;6(1):190-206.
    PMID: 24384995 DOI: 10.3390/nu6010190
    Iron deficiency anaemia (IDA) is the most common nutritional deficiency in the world including developed and developing countries. Despite intensive efforts to improve the quality of life of rural and aboriginal communities in Malaysia, anaemia and IDA are still major public health problems in these communities particularly among children. A randomized, double-blind, placebo-controlled trial was conducted on 250 Orang Asli (aboriginal) schoolchildren in Malaysia to investigate the effects of a single high-dose of vitamin A supplementation (200,000 IU) on iron status indices, anaemia and IDA status. The effect of the supplement was assessed after 3 months of receiving the supplements; after a complete 3-day deworming course of 400 mg/day of albendazole tablets. The prevalence of anaemia was found to be high: 48.5% (95% CI=42.3, 54.8). Moreover, 34% (95% CI=28.3, 40.2) of the children had IDA, which accounted for 70.1% of the anaemic cases. The findings showed that the reduction in serum ferritin level and the increments in haemoglobin, serum iron and transferrin saturation were found to be significant among children allocated to the vitamin A group compared to those allocated to the placebo group (p<0.01). Moreover, a significant reduction in the prevalence of IDA by almost 22% than prevalence at baseline was reported among children in the vitamin A group compared with only 2.3% reduction among children in the placebo group. In conclusion, vitamin A supplementation showed a significant impact on iron status indices and IDA among Orang Asli children. Hence, providing vitamin A supplementation and imparting the knowledge related to nutritious food should be considered in the efforts to improve the nutritional and health status of these children as a part of efforts to improve the quality of life in rural and aboriginal communities.
    Matched MeSH terms: Anemia, Iron-Deficiency/blood; Anemia, Iron-Deficiency/drug therapy*; Anemia, Iron-Deficiency/epidemiology; Iron, Dietary/administration & dosage*; Iron, Dietary/blood
  5. Tee ES, Kandiah M, Awin N, Chong SM, Satgunasingam N, Kamarudin L, et al.
    Am J Clin Nutr, 1999 Jun;69(6):1249-56.
    PMID: 10357747 DOI: 10.1093/ajcn/69.6.1249
    BACKGROUND: Iron deficiency and its consequent anemia constitute the commonest micronutrient deficiency in the world.
    OBJECTIVE: We investigated whether long-term, weekly iron-folate supplements administered at school would improve hemoglobin and ferritin concentrations in adolescent girls, including those with mild-to-moderate anemia and hemoglobin concentrations indicating borderline anemia.
    DESIGN: Subjects were 266 girls with hemoglobin concentrations of 80-119.9 g/L (group A) and 358 girls with hemoglobin concentrations of 120-130 g/L (group B) who were otherwise healthy. Two hundred sixty-six girls in group A and 268 girls in group B were randomly assigned to receive either 60 or 120 mg Fe plus 3.5 mg folic acid weekly for 22 wk. Ninety of the girls in group B were randomly assigned to receive only 5 mg folic acid weekly. Capillary hemoglobin and plasma ferritin were measured at baseline and after 12 and 22 wk of supplementation.
    RESULTS: By the end of the study, 2% of the girls had dropped out and > 96% had taken > or = 20 of the 22 tablets; side effects were minimal. Mean plasma ferritin increased significantly in all iron-supplemented groups, independently of initial hemoglobin values and iron doses. Ferritin concentrations decreased in the girls supplemented with folic acid only. As expected, hemoglobin responses to iron were higher in group A than in group B and increases were positively correlated with initial plasma ferritin. Hemoglobin failed to respond to folate supplementation if initial plasma ferritin concentrations were low. Mean hemoglobin increased significantly and consistently in relation to the length of treatment.
    CONCLUSION: Long-term, weekly iron-folate supplementation was found to be a practical, safe, effective, and inexpensive method for improving iron nutrition in adolescent schoolgirls.

    Comment in: Picciano MF. Iron and folate supplementation: an effective intervention in
    adolescent females. Am J Clin Nutr. 1999 Jun;69(6):1069-70. PubMed PMID:
    10357724. https://academic.oup.com/ajcn/article/69/6/1069/4714856

    Study site: 3 secondary schools, Samarahan district, Sarawak, Malaysia
    Matched MeSH terms: Iron/administration & dosage; Iron/therapeutic use*; Anemia, Iron-Deficiency/blood; Anemia, Iron-Deficiency/classification; Anemia, Iron-Deficiency/drug therapy*
  6. Yusoff H, Daud WN, Ahmad Z
    PMID: 23082570
    A higher occurrence of iron deficiency anemia is present in rural Malaysia than urban Malaysia due to a lower socio-economic status of rural residents. This study was conducted in Tanah Merah, a rural district of Kelantan, Malaysia. Our objective was to investigate the impact of nutrition education alone, daily iron, folate and vitamin C supplementation or both on knowledge, attitudes and hemoglobin status of adolescent students. Two hundred eighty fourth year secondary students were each assigned by school to 1 of 4 different treatment groups. Each intervention was carried out for 3 months followed by 3 months without treatment. A validated self-reported knowledge and attitude questionnaire was administered; hemoglobin levels were measured before and after intervention. At baseline, no significant difference in hemoglobin was noted among the 4 groups (p = 0.06). The changes in hemoglobin levels at 3 months were 11, 4.6, 3.9 and -3.7% for the supplementation, nutrition education, combination and control groups, respectively. The changes at 6 months were 1.0, 6.8, 3.7 and -14.8%, respectively. Significant improvements in knowledge and attitude were evidenced in both the nutritional education and combination groups. The supplementation and control groups had no improvement in knowledge or attitudes. This study suggests nutritional education increases knowledge, attitudes and hemoglobin levels among Malaysian secondary school adolescents.
    Matched MeSH terms: Iron/administration & dosage; Anemia, Iron-Deficiency/epidemiology; Anemia, Iron-Deficiency/prevention & control*
  7. Shukri A, Green S, Bradley DA
    Appl Radiat Isot, 1995 6 1;46(6-7):625.
    PMID: 7633384
    Matched MeSH terms: Iron/analysis*; Iron/metabolism; Iron Chelating Agents/therapeutic use
  8. Ismail A
    Biochem Biophys Res Commun, 1988 Jan 15;150(1):18-24.
    PMID: 2962581
    This study was initiated to determine the mechanism of iron-uptake in Salmonella typhi. When stressed for iron, microorganisms produce siderophores to obtain the necessary nutrient. Generally two types of siderophores exist: the phenolate-type predominantly produced by bacteria and the hydroxamate-type commonly secreted by fungi. Results of this investigation showed that S. typhi produced siderophores of the phenolate-type since culture supernatant of the organism grown under iron-deprivation supported the growth of the phenolate-dependent auxotroph. The culture supernatant when extracted for phenolate siderophores, also supported the growth of the phenolate auxotroph but not the hydroxamate auxotroph. Production of phenolate-type siderophores were further confirmed using biochemical assays. These results showed that S. typhi utilized the high-affinity iron transport system to obtain the necessary iron.
    Matched MeSH terms: Iron/metabolism; Iron Chelating Agents/metabolism*; Iron Chelating Agents/pharmacology
  9. Jalambo MO, Karim NA, Naser IA, Sharif R
    Public Health Nutr, 2018 Oct;21(15):2793-2802.
    PMID: 29911513 DOI: 10.1017/S1368980018001568
    OBJECTIVE: The present study aimed to determine the prevalence of anaemia, iron deficiency (ID) and iron-deficiency anaemia (IDA) among female adolescents in the Gaza Strip, Palestine, as well as the risk factors involved in these conditions.

    DESIGN: The study was conducted using the quantitative descriptive method with a cross-sectional design. Data were collected using an FFQ and sociodemographic, sedentary behaviour and physical activity questionnaires. Anthropometric measurements and blood analyses were also conducted.

    SETTING: The study population included all Palestinian female adolescents enrolled in secondary schools in the academic years 2015-2016. Five female secondary schools were selected randomly from five governorates of the Gaza Strip.

    SUBJECTS: Female adolescents (n 330) aged 15-19 years in the selected secondary schools were enrolled randomly.

    RESULTS: Prevalence of anaemia, ID and IDA among female adolescents in the Gaza Strip, Palestine, was 35·8, 40·3 and 26·0 %, respectively. A significant association (P<0·05) existed between ID, anaemia and IDA and dietary habits, including skipping breakfast and amount of junk food intake. Also, low consumption of fruits and vegetables was associated with IDA in the female adolescents. A statistically significant association was found between mother's education and ID but not with the other sociodemographic factors.

    CONCLUSIONS: The study shows that there is an alarming problem of anaemia and IDA in the Gaza Strip, Palestine. This may indicate that there are insufficient nutrition education programmes, particularly inside schools or by the mass media.

    Matched MeSH terms: Iron/blood; Anemia, Iron-Deficiency/etiology; Anemia, Iron-Deficiency/epidemiology*
  10. Menon KC, Ferguson EL, Thomson CD, Gray AR, Zodpey S, Saraf A, et al.
    Nutrition, 2014 Mar;30(3):291-6.
    PMID: 24484679 DOI: 10.1016/j.nut.2013.08.015
    The aim of this study was to investigate the iron status of pregnant tribal women from Ramtek, Nagpur, Maharashtra, India using a combination of indices.
    Matched MeSH terms: Anemia, Iron-Deficiency/blood; Anemia, Iron-Deficiency/epidemiology*; Iron, Dietary/administration & dosage*; Iron, Dietary/blood*
  11. Al-Mekhlafi MH, Surin J, Atiya AS, Ariffin WA, Mahdy AK, Abdullah HC
    Trans R Soc Trop Med Hyg, 2008 Oct;102(10):1046-52.
    PMID: 18617209 DOI: 10.1016/j.trstmh.2008.05.012
    A cross-sectional study to determine the current prevalence of anaemia and iron deficiency anaemia (IDA) and to investigate the possible risk factors for IDA was carried out on 241 aboriginal schoolchildren (120 boys, 121 girls) aged 7-12 years and living in remote areas in Pos Betau, Pahang, Malaysia. Haemoglobin (Hb) level was measured and serum iron status was assessed by serum ferritin (SF), serum iron (SI) and total iron binding capacity measurements. Socioeconomic data were collected using pre-tested questionnaires. All children were screened for intestinal parasitic infections. Overall, 48.5% (95% CI 42.3-54.8) of children were anaemic (Hb<12 g/dl). The prevalence of IDA was 34% (95% CI 28.3-40.2), which accounted for 70.1% of the anaemia cases. The prevalence of IDA was significantly higher in females than males. Low levels of mothers' education and low household income were identified as risk factors for IDA. Severe trichuriasis also found to be associated with low SF and SI. Logistic regression confirmed low levels of mothers' education and gender as significant risk factors for IDA. Improvement of socioeconomic status and health education together with periodic mass deworming should be included in public health strategies for the control and prevention of anaemia and IDA in this population.
    Matched MeSH terms: Iron/deficiency; Anemia, Iron-Deficiency/ethnology; Anemia, Iron-Deficiency/epidemiology*; Anemia, Iron-Deficiency/parasitology
  12. Aini UN, Al-Mekhlafi MS, Azlin M, Shaik A, Sa'iah A, Fatmah MS, et al.
    Asia Pac J Clin Nutr, 2007;16(4):724-30.
    PMID: 18042535
    We conducted a cross sectional study to examine the association of intestinal parasitic infections and protein energy malnutrition (PEM) with iron-status indicators and anaemia among Orang Asli children in Selangor, Malaysia. A total of 281 children aged 2 - 15 years were studied. The data were collected using structured questionnaires, anthropometric measurements and laboratory analysis for blood and faecal samples. All children were infected either by A. lumbricoides, T. trichiura or hookworm and almost 19%, 26% and 3% of the children had severe infection of ascariasis, trichuriasis and hookworm infection respectively. The prevalence of giardiasis among them was 24.9%. Overall, 41.5% of the children were anaemic (haemoglobin < 11.0 g/dL). Of these 61.0% of the children had iron deficiency and 36.5% had iron deficiency anaemia (IDA), which accounted for 88.0% of anaemia in this population. Severe trichuriasis had the most significant correlation with anaemia and iron deficiency in this population. It contributed to low concentrations of haemoglobin, serum iron and serum ferritin and high total iron binding capacity (TIBC). Significant underweight and stunting were associated with low concentrations of haemoglobin and serum iron while significant wasting was significantly associated with low concentration of serum ferritin. Logistic regression analysis confirmed that severe trichuriasis was a strong predictor of IDA. It also confirmed that children who were significantly underweight and whose mother was working were independent predictors of IDA in this population.
    Matched MeSH terms: Iron/blood*; Iron/deficiency; Anemia, Iron-Deficiency/blood*; Anemia, Iron-Deficiency/epidemiology
  13. Foo LH, Khor GL, Tee ES, Prabakaran D
    Asia Pac J Clin Nutr, 2004;13(1):48-55.
    PMID: 15003914
    Iron deficiency anaemia (IDA) is the most prevalent micronutrient deficiency in the world affecting the general health and wellbeing of millions. In Malaysia, moderately high prevalences of anaemia have been reported amongst infants, young children and women of childbearing age. Data is scant for the adolescents. This study was undertaken to assess the iron status and dietary intake of 165 adolescents, comprising 74 male and 91 female subjects, aged 12 to 19 years, from the rural communities in Tuaran District of Sabah, Malaysia. Convenience sampling was used for the selection of study subjects. Multiple iron status indicators namely, serum ferritin (SF), transferrin saturation (TS), mean corpuscular volume (MCV) and haemoglobin (Hb) were determined for the study. The mean age of the subjects was 15.2 +/-2.1 years. While the majority of the subjects (77.6%) had normal body mass index (BMI) values, 17.6% were underweight and 4.8% overweight. About 35% to 40% of the subjects showed deficient values for haematocrit, serum ferritin, serum iron, mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV) and transferrin saturation (TS), and 20% were anaemic (Hb <12 g/L). Using the multiple criteria of iron status indicators, the prevalence of iron depletion, iron deficiency and IDA in the male and female adolescents were 5.4% vs. 6.6%, 18.9% vs. 26.4% and 5.4% vs. 26.4%, respectively. Iron deficiency anaemia (85.0%) contributed largely to the prevalence of anaemia. The dietary iron intake of the adolescents was unsatisfactory, with approximately 98% of subjects failing to meet the Malaysian RDA level. Almost all the female subjects (91%) had dietary iron intake below two-thirds of the RDA level compared with a much smaller proportion for the male adolescents (68%). The prevalence of IDA in the present study population, especially in the female adolescents, appears to be a significant public health problem. Priority should therefore be given to the eradication of iron deficiency in adolescents from low-income areas by dietary modification and micronutrient supplementation amongst female adolescents.
    Matched MeSH terms: Iron/blood*; Anemia, Iron-Deficiency/epidemiology*; Iron, Dietary/administration & dosage*
  14. Viprakasit V, Lee-Lee C, Chong QT, Lin KH, Khuhapinant A
    Int J Hematol, 2009 Nov;90(4):435-445.
    PMID: 19862602 DOI: 10.1007/s12185-009-0432-0
    Worldwide, thalassemia is the most commonly inherited hemolytic anemia, and it is most prevalent in Asia and the Middle East. Iron overload represents a significant problem in patients with transfusion-dependent beta-thalassemia. Chelation therapy with deferoxamine has traditionally been the standard therapeutic option but its usage is tempered by suboptimal patient compliance due to the discomfort and demands associated with the administration regimen. Therefore, a great deal of attention has been focused on the development of oral chelating agents. Deferiprone, even though available for nearly two decades in Asia with recent encouraging data on cardiac iron removal and long-term efficacy, has serious adverse effects including agranulocytosis and neutropenia which has impeded it from routine clinical practice. A novel oral chelator; deferasirox is effective throughout a 24 h dosing period and both preclinical and clinical data indicate that it successfully removes both hepatic and cardiac iron. In Asia, optimal management of severe thalassemia patients and the availability and access to oral iron chelators still presents a major challenge in many countries. In this regard, the development and implementation of consensus guidelines for management of Asian patients with transfusion-dependent thalassemia will be a major step towards improving and maintaining the continuity of patient care.
    Matched MeSH terms: Iron Chelating Agents/administration & dosage; Iron Chelating Agents/pharmacology; Iron Chelating Agents/therapeutic use*; Iron Overload/drug therapy*
  15. Asghar A, Abdul Raman AA, Daud WM
    ScientificWorldJournal, 2014;2014:869120.
    PMID: 25258741 DOI: 10.1155/2014/869120
    In the present study, a comparison of central composite design (CCD) and Taguchi method was established for Fenton oxidation. [Dye]ini, Dye:Fe(+2), H2O2:Fe(+2), and pH were identified control variables while COD and decolorization efficiency were selected responses. L 9 orthogonal array and face-centered CCD were used for the experimental design. Maximum 99% decolorization and 80% COD removal efficiency were obtained under optimum conditions. R squared values of 0.97 and 0.95 for CCD and Taguchi method, respectively, indicate that both models are statistically significant and are in well agreement with each other. Furthermore, Prob > F less than 0.0500 and ANOVA results indicate the good fitting of selected model with experimental results. Nevertheless, possibility of ranking of input variables in terms of percent contribution to the response value has made Taguchi method a suitable approach for scrutinizing the operating parameters. For present case, pH with percent contribution of 87.62% and 66.2% was ranked as the most contributing and significant factor. This finding of Taguchi method was also verified by 3D contour plots of CCD. Therefore, from this comparative study, it is concluded that Taguchi method with 9 experimental runs and simple interaction plots is a suitable alternative to CCD for several chemical engineering applications.
    Matched MeSH terms: Iron/chemistry*
  16. Shah I, Adnan R, Ngah WS, Mohamed N, Taufiq-Yap YH
    Bioresour Technol, 2014 May;160:52-6.
    PMID: 24630369 DOI: 10.1016/j.biortech.2014.02.047
    To enhance the potential of activated carbon (AC), iron incorporation into the AC surface was examined in the present investigations. Iron doped activated carbon (FeAC) material was synthesized and characterized by using surface area analysis, energy dispersive X-ray (EDX), temperature programmed reduction (TPR) and temperature programmed desorption (TPD). The surface area of FeAC (543 m(2)/g) was found to be lower than AC (1043 m(2)/g) as a result of the pores widening due to diffusion of iron particles into the porous AC. Iron uploading on AC surface was confirmed through EDX analysis, showing up to 13.75 wt.% iron on FeAC surface. TPR and TPD profiles revealed the presence of more active sites on FeAC surface. FeAC have shown up to 98% methylene blue (MB) removal from the aqueous media. Thermodynamic parameters indicated the spontaneous and exothermic nature of the sorption processes.
    Matched MeSH terms: Iron/chemistry*
  17. Hasan DB, Abdul Raman AA, Daud WM
    ScientificWorldJournal, 2014;2014:252491.
    PMID: 24592152 DOI: 10.1155/2014/252491
    The mineralisation kinetics of petroleum refinery effluent (PRE) by Fenton oxidation were evaluated. Within the ambit of the experimental data generated, first-order kinetic model (FKM), generalised lumped kinetic model (GLKM), and generalized kinetic model (GKM) were tested. The obtained apparent kinetic rate constants for the initial oxidation step (k'2), their final oxidation step (k'1), and the direct conversion to endproducts step (k3') were 10.12, 3.78, and 0.24 min(-1) for GKM; 0.98, 0.98, and nil min(-1) for GLKM; and nil, nil, and >0.005 min(-1) for FKM. The findings showed that GKM is superior in estimating the mineralization kinetics.
    Matched MeSH terms: Iron/chemistry*
  18. Azma RZ, Ainoon O, Azlin I, Hamenuddin H, Hadi NA, Tatt WK, et al.
    Clin Ter, 2012 Jul;163(4):287-91.
    PMID: 23007811
    Anaemia is a global health problem including Malaysia. In adults, anaemia may affect work productivity. Iron deficiency anaemia and thalassaemia are common causes of anaemia in Malaysia. However, there is scarcity of data on national prevalence of iron deficiency anaemia and thalassaemia, especially in young adults. This cross sectional study was performed to determine the prevalence of iron deficiency anaemia and thalassaemia among medical students of Universiti Kebangsaan Malaysia Medical Centre (UKMMC).
    Matched MeSH terms: Anemia, Iron-Deficiency/epidemiology*
  19. Hasan DB, Abdul Aziz AR, Daud WM
    Environ Technol, 2012 Jun;33(10-12):1111-21.
    PMID: 22856280
    The mineralisation of remazol black B (RBB) was studied at concentrations ranging from 20-1000 mgL(-1). The work was aimed at investigating the Fenton-like peroxidation of RBB at a concentration typically obtained in Batik cottage industries. Other response parameters were degradation and colour removal efficiencies. The parameters that were measured included total organic carbon (TOC), chemical oxygen demand (COD) as well as absorbance for mineralisation, degradation and colour. To optimise the process, the interaction effects of several controlling variables on the treatment process were examined using dispersion matrix-optimal design and response surface analysis. Four specific variables: initial dye concentration (Dye)o; the molar ratio of oxidant to dye organic strength (H2O2):(COD); the mass ratio of the oxidant to the catalyst (H2O2):(Fe3+) and reaction time (t(r)), were observed. Three reduced empirical models, one for each response, were developed for describing the treatment process. For 20, 510 and 1000 mgL(-1), the optimum %TOC reduction and oxidation times were 44% for 95 min, 52% for 52.5 min and 68% for 10 min corresponding to 67, 81 and 75% COD reduction, respectively. The optimum COD reduction and oxidation times were 89% for 95 min, 91% for 10 min and 84% for 95 min for concentrations of 20, 510 and 1000 mg L(-1), respectively. For all concentrations, total colour removal was achieved. A comparison of the results obtained in this study with literature values for traditional Fenton, photo-Fenton and photo-Fenton-like oxidation indicated that the TOC reduction obtained using the Fenton-like process was satisfactory.
    Matched MeSH terms: Iron/chemistry*
  20. Mohajeri S, Aziz HA, Isa MH, Bashir MJ, Mohajeri L, Adlan MN
    PMID: 20390917 DOI: 10.1080/10934521003648883
    This study evaluated the effectiveness of Fenton's technique for the treatment of semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. The Fe2+ or Fe3+ as catalyst and H2O2 as oxidizing agent are commonly used for the classical Fenton's reaction. In present study, the effect of operating conditions such as pH, reaction time, molar ratio, agitation rate, feeding mode and Fenton reagent concentrations which are important parameters that affect the removal efficiencies of Fenton method were investigated. Under the most favorable conditions, the highest removals of 58.1 and 78.3% were observed for COD and color, respectively. In general, the best operating conditions were pH = 3, Fe = 560 mg L(-1), H2O2 = 1020 mg L(-1), H2O2/Fe2+ molar ratio = 3, agitation rate = 400 rpm and reaction time = 120 minutes. The results highlighted that stepwise addition of Fenton's reagent was more effective than adding the entire volume in a single step. Excessive hydrogen peroxide and iron have shown scavenging effects on hydroxyl radicals and reduced degradation of refractory organics in the landfill leachate.
    Matched MeSH terms: Iron/chemistry*
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