Islam M.R.,Bangladesh University of Engineering and Technology |
Podder J.,Bangladesh University of Engineering and Technology |
Farhad S.F.U.,BCSIR Laboratories |
Saha D.K.,Atomic Energy Center
Sensors and Transducers | Year: 2011
Nano fiber ZnO films have been deposited on to glass substrate at 200 °C by a simple spray pyrolysis technique under atmospheric pressure. The effect of annealing temperature on the structural and optical properties of the as grown films has been studied by Scanning Electron Microscopy (SEM) attached with an EDX, powder X-ray diffraction and UV visible spectroscopy. The atomic weight % of Zinc and Oxygen were found to be 49.22 % and 49.62 % respectively. The SEM micrographs show nano fiber structure and uniform deposition on the substrate. Average grain size of ZnO thin film was found in the range of 21 to 27 nm. The lattice constant a and c of ZnO thin film are determined at different annealing temperatures and values are found slightly larger than those of JCPDS data and lower for the sample annealed at 600 °C. The lattice parameters a and c decrease with increasing temperature. It reveals that the samples are poly-crystalline and having with low densities. Band gap energy of ZnO was found in the range of 3.33 to 3.17 eV and decreases with the increase of the annealing temperature. © 2011 IFSA.
Islam F.,University of Rajshahi |
Islam F.,Griffith University |
Khanam J.A.,University of Rajshahi |
Khatun M.,University of Rajshahi |
And 8 more authors.
Phytotherapy Research | Year: 2015
Anticancer activities of p-menth-1-ene-4,7-diol (EC-1) isolated from Eucalyptus camaldulensis Dhnh. were studied on Ehrlich ascites carcinoma (EAC) cells by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Anticancer activities also analyzed in EAC-bearing mice by assessment of cancer growth inhibition, changes in cancer volume, changes in life span, and hematological parameters. Apoptosis was analyzed by fluorescence microscope, DNA fragmentation assay, and flow cytometry. The expression of apoptosis-related genes, Bcl-2, Bcl-X, PARP-1, p53, and Bax, were analyzed using polymerase chain reaction (PCR). EC-1 significantly inhibited proliferation of EAC cells in vivo and restored the altered hematological parameters of EAC-bearing mice. Cytological observation by fluorescence microscope showed apoptosis of EAC cells upon treatment with EC-1. Also, DNA fragmentation assay revealed EAC cells' apoptosis following EC-1 treatment. Increased mRNA expressions of p53 and Bax genes and negative expressions of Bcl-2 and Bcl-X were observed in cells treated with EC-1. These findings confirmed the induction of apoptosis by EC-1. In addition, MTT assay showed dose-dependent anticancer activity of EC-1 against EAC cell. Cell cycle analysis revealed that EC-1 treatment caused suppression of EAC cells at S phase. To conclude, EC-1 is a novel anticancer compound and showed antiproliferative and apoptotic activities in cellular and mice models. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Ashraf M.A.,Bangladesh University |
Bhuiyan A.H.,Bangladesh University of Engineering and Technology |
Hakim M.A.,Atomic Energy Center Dhaka |
Hossain M.T.,BCSIR Laboratories
Physica B: Condensed Matter | Year: 2010
The microstructure and electrical properties of Ho2O3 doped Bi2O3-based ZnO varistor ceramics were investigated. The bulk density varies between 5.41 and 5.47 g cm-3 with the maximum value of 5.47 g cm-3 for 0.50 mol% Ho 2O3 content. The average grain size for all the samples was calculated from the scanning electron micrographs and were found between 5.1 and 7.1 μm. The microstructure of the prepared samples shows a decrease in grain size of ZnO phase with Ho2O3 doping. The energy dispersive X-ray analysis and X-ray diffraction analysis of the samples show the presence of ZnO, Bi-rich, spinel Zn7Sb2O12 and Ho2O3-based phases. The nonlinear coefficient, α, obtained from electric fieldcurrent density plots has a maximum value of 78 for the ceramics with 0.50 mol% Ho2O3 content. The leakage current, IL, has a minimum value of 1.30 μA for the 0.50 mol% Ho2O3 doped ZnO varistor ceramics. The breakdown field, Eb, was found to increase with Ho2O3 content. © 2010 Elsevier B.V. All rights reserved.
Talukder A.I.,University of Dhaka |
Sultana P.,University of Dhaka |
Haider A.F.M.Y.,University of Dhaka |
Wahadoszamen M.,University of Dhaka |
And 2 more authors.
European Physical Journal D | Year: 2010
Silver nanoparticles have been produced by laser ablation of silver metal in nanopure water without any chemical additives. It has been observed that laser power has a control over the size of the nanoparticles. Increasing laser power shows a clear blue shift in the absorption peak of fabricated nanoparticles indicating that the average size of the particles decreases with increasing laser power. Ablation for longer period reduces the average size of nanoparticles which is attributed to the re-ablation of fabricated nanoparticles. A good correlation has been observed between the peak of the absorption spectrum measured by UV-VIS spectroscopy and the average particle size measured by scanning electron microscope imaging method. The value of the coefficient of correlation is determined to be 0.965. © 2010 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.
Ali M.A.,University of Technology Malaysia |
Sayeed M.A.,University of Rajshahi |
Alam M.S.,University of Rajshahi |
Yeasmin M.S.,BCSIR Laboratories |
And 2 more authors.
Bulletin of the Chemical Society of Ethiopia | Year: 2012
The core objective of this research was to determine the oil characteristics and nutrient contents of Nigella sativa and Trigonella foenum-graecum seeds. Characteristics of seed oils revealed higher degree of unsaturation and as determined by gas liquid chromatography (GLC) reported herein the major unsaturated fatty acids were linoleic acid (52.6% in N. sativa and 42.5% in T. foenum-graecum), followed by oleic acid (23.5% in N. sativa and 20% in T. foenum-graecum), while the main saturated fatty acid was palmitic acid (16% in N. sativa and 10.5% in T. foenum-graecum). Triacylglycerols and neutral lipids were found to be most abounded components recorded to 78.4 and 93.2% for N. sativa and 84.8 and 93.2% for T. foenum-graecum, respectively. The seed oils, therefore, have potential for use as domestic and industrial oils. Compositional analysis revealed that both samples contained considerable amounts of protein (20% in N. sativa and 28% in T. foenum-graecum) and high amount of lipid (37%) in N. sativa seeds. The seeds are shown to be rich sources of potassium, calcium and sodium and other elements. Nutrient information reported herein illustrates the benefits to public health for consumers of these plant seeds. © 2012 Chemical Society of Ethiopia.
Akther Hossain A.K.M.,Bangladesh University of Engineering and Technology |
Rahman M.A.,Bangladesh University of Engineering and Technology |
Farhad S.F.U.,BCSIR Laboratories |
Vilquin B.,École Centrale Lyon |
Tanaka H.,Osaka University
Physica B: Condensed Matter | Year: 2011
Structural and magnetic properties of a series of polycrystalline spinel type ferrites with the nominal chemical composition LixMg 0.40Ni0.60-2xFe2+xO4, where x=0.00.3 in steps of 0.05, were investigated thoroughly. The formation of spinel structure was confirmed by X-ray diffraction analysis. Lattice constants and average grain diameters increased with increase in Li content. The real part of the initial permeability (μ/i) is found to increase not only with increase in Li content up to x=0.25 but also with the increase in sintering temperature up to 1100 °C. However, it decreases for further increase in sintering temperature except for x=0 and 0.05 compositions. The grain size dependent μ/i is also observed clearly in this research. From the magnetization as a function of applied magnetic field plots, it is clear that all samples exhibit ferrimagnetic state at room temperature and have a low saturation field. The magnetization obtained is explained with the help of redistribution of cations in the tetrahedral and octahedral sites and spin canting due to weakening of exchange interaction. © 2011 Elsevier B.V. All rights reserved.
Nuruddin M.,University of Dhaka |
Chowdhury A.,University of Dhaka |
Haque S.A.,University of Dhaka |
Rahman M.,Pulp and Paper Research Division |
And 3 more authors.
Cellulose Chemistry and Technology | Year: 2011
The compositional characteristics of rice straw, wheat straw, corn stalks and dhaincha were established in terms of lignin, cellulose and hemicellulose contents, to assess the suitability of agricultural wastes for the extraction of microfibrils. Cellulose microfibrils were prepared by sulphuric acid hydrolysis from these raw materials, which had previously been submitted to a fractionation process by formic acid/peroxyformic acid/peroxide. Cellulose, amounting to 37-43%, lignin (16-20%), hemicelluloses (20-33%) and other compounds were extracted. The extracted cellulose microfibrils were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and X-ray diffraction. All cellulose microfibril samples showed good thermal stability. The extracted microfibrils presented triclinic structure.
Begum J.,BCSIR Laboratories |
Bhuiyan Md.N.I.,BCSIR Laboratories |
Taznin T.,BCSIR Laboratories
Asian Journal of Microbiology, Biotechnology and Environmental Sciences | Year: 2010
The essential oil from aerial parts of Eupatorium triplinerve Vahl. was analyzed by gas chromatography mass spectroscopy(GC-MS). Thirty compounds representing 98.25% of the oil were identified. The major components were 2-tert-butyl-1,4-methoxybenzene (74.3%) and β-selinene (8.6%). The antimicrobial activity of the essential oil was evaluated against ten bacteria (including Gram positive and Gram negative) and six phytopathogenic fungi. The oil exhibited moderate antibacterial and strong antifungal activities against all the test pathogens. The highest antibacterial activity was recorded against Salmonella typhi (23mm) followed by Shigella sonnei (19mm) at a concentration of 20μl/disc. The highest antifungal activity was recorded against Macrophomina phaseolina (85%) followed by Botrydiplodia theobromae (84%) which are better in comparison with standard Nystatin. © Global Science Publications.
Khondker M.,University of Dhaka |
Hassan M.A.,University of Dhaka |
Alfasane M.A.,University of Dhaka |
Shahjadee U.F.,University of Dhaka |
Shahjadee U.F.,BCSIR Laboratories
Bangladesh Journal of Plant Taxonomy | Year: 2010
Monitoring on the panicle initiation, flowering, fruiting and seedling characteristics of Corypha taliera has been carried out. Biochemical composition of fresh and dry flowers together with the pericarp of the fruits have been analysed. Fresh flowers, fruits, seeds, and pericarp and testa weighed 13.75 mg/flower, 19.46 g/fruit, 6.47 g/seed, 12.89 g/pericarp and testa, respectively. The length of fruits and seeds were c 3.34 cm and c 2.33 cm, respectively while the breadth of the same were 3.14 cm and 1.94 cm, respectively. The protein content of fresh flower and pericarp were 12.78 and 14.70%. High energy content 345.97 Kcal was recorded in the pericarp and testa of the fruit. The first sown seeds were germinated in latterite clay soil between January and February and took approximately 30-48 days. © 2010 Bangladesh Association of Plant Taxonomists.
Sarker M.S.R.,University of Dhaka |
Alam M.Z.,University of Dhaka |
Qadir M.R.,Bangladesh Council of Scientific and Industrial Research BCSIR |
Gafur M.A.,Bangladesh Council of Scientific and Industrial Research BCSIR |
Moniruzzaman M.,BCSIR Laboratories
International Journal of Minerals, Metallurgy and Materials | Year: 2015
A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was extracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Aluminum dross samples were found to approximately contain 75wt% Al2O3 and 12wt% SiO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extraction of alumina were studied to optimize the dissolution process. First, Al(OH)3 was produced in the form of a gel. Calcination of the Al(OH)3 gel at 1000°C, 1200°C, and 1400°C for 2 h produced γ-Al2O3, (α+γ)-Al2O3, and α-alumina powder, respectively. Thermal characterization of the Al(OH)3 gel was performed by thermogravimetric/differential thermal analysis (TG/DTA) and differential scanning calorimetry (DSC). The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence (XRF) spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials. © 2015, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.