Recent developments in computer-aided polymer processing have brought along the need for accurate description of the behavior of materials under the conjugated effect of applied stress and temperature. In order to serve this purpose, in this study, experimental data provided by uniaxial tensile technique tests for thermoplastic halter (CTPH) comprised of hyperelastic materials when subjected to combined effects of applied stress and temperature are coupled with numerical simulations to obtain the required parameters for the characterization of such materials. First, stresses and displacements the thermoplastic halter are recorded during experiment. Thereafter, Mooney-Rivlin's and Ogden theory of hyperelastic is employed to define the constitutive model of thermoplastic halter (CTPH) and nonlinear equilibrium equations of the process are solved using finite element method with Abaqus software. As a last step, a neuronal algorithm (ANN model) is employed to minimize the difference between calculated and measured parameters to determine material constants for Mooney-Rivlin and Ogden models. Although the developed procedure can be applied to several polymeric materials, in this paper, this technique is successfully implemented for acrylonitrile–butadiene–styrene (ABS). Using these coefficients, the material behavior of ABS with Mooney-Rivlin and Ogden constitutive laws is reproduced. The material model obtained in this study for ABS can be implemented into industrial and academic softwares for applications and design purposes.
Adverse effects of climate change such as drought continue to be a major threat to rural livelihoods. This study investigates farmers’ perceptions of climate change and adaptation process through food consumption and food habit change using a two community peoples’ perception in Kurigram district Bangladesh. Study revealed that the daily livelihoods has affected due to climate change. Farmers’ perceptions on adaptation to droughts were associated with food habit change. However, food habit change is not the complete solution. This may be an adaptation to the changes that may real, controllable and within their reach. Therefore, people have to adapt to climate change such as drought and do that by producing and promoting fresh, sustainable, reachable, cost effective crops that can withstand environmental changes through food habit change. The extent to which farmers’ perceived agricultural diversity as a climate changes adaptation strategy may suitable.
The Sr3B2O6:Tb3+ phosphors with different concentration of Tb3+ were prepared by combustion method combination with heating at high-temperature. Results of the crystalline structure measurement indicate that the Sr3B2O6:Tb3+ phosphors have a Rhomboidal single phase. The excitation spectra show that the phosphors can be excited by ultraviolet light of near 379 nm. The emission spectra under 379 nm excitation includes several narrow lines, which is 5D4-7Fj (j = 2, 3, 4, 5, 6) transitions of Tb3+ ion in the lattice. The emission intensity of Tb3+ in Sr3B2O6 is influenced by the Tb3+ doping content and optimum concentration is 3%mol. The concentration quenching of Tb3+ in this phosphor occurs when Tb3+ concentration is over 3%mol. The concentration quenching mechanism was determined dipole-quadrupole (d-q) interaction by using Dexter’s theory.
This paper presents detailed modelling of a grid-connected photovoltaic (PV) system components. The study is helpful to understand the working principles of the PV system. The performance of the system has been discussed by means of a Matlab/Simulink Toolbox. The results show that the PV system capable of tracking the maximum power point (MPP) quickly and precisely in case of sudden changes in solar radiation, cell temperature, and in case of existence of sand. Under the non-uniform atmospheric conditions, to get a high performance of the PV system, appropriate converters are required to operate at the MPP.
Currently, Malaysia like other Asian countries has experienced rapid expansion of urbanization. This expansion is at the expense of agriculture land at the fringe and rural areas, thus affecting the likelihood and culture of the rural communities. In order to achieve sustainable development, an understanding of public attitudes towards environmental/developmental issues is essential. Residents ''perceptions towards urban development is relatively under researched as there is a wide gaps between the need of the planners and the desire of local communities particularly in the developing countries. Therefore, the aim of this paper is to investigate how residents of Balik Pulau perceive the pressure of urban development going on around them. A questionnaire was designed to request opinions from 320 respondents randomly chosen from residents living in Balik Pulau of Malaysia. The findings showed that local community feel that the expansion of urban development obliterate agricultural activities, food security, and natural environment existence. More than 50% of the respondents have showed negative attitude towards urbanization with some felt that urbanization caused environmental problem and led to social illness. The local community is willing to participate in achieving sustainable development but, they are lacking information to understand environmental/development issues. Consequently, for the onus is on the planners and policy makers to incorporate the desires of the local inhabitants while drafting urbanization planning in Balik Pulau area which would be helpful in formulating sustainable development projects. It will ultimately help in preservation, conservation and development of Balik Pulau area.
Aims: This study was undertaken to know the effect of different preservatives on the nutritional and microbial quality of wheat flour cake Study Design: To assess the effect of sodium propionate, food grade alcohol (Brandy) and sodium bicarbonate on the nutritional and microbial load of preserved cake using unpreserved cake as a control. Place and Duration of Study: Samples were purchased from Bida Modern Market Niger State, Nigeria. Analyze at Central Services Laboratory of National Cereal Research Institute, Badeggi, Niger State. Experiment was conducted between September 2013 and April 2014. Methodology: Wheat flour cake was produced using wheat flour, fat sugar, salt, milk, eggs and three different preservatives: sodium bicarbonate, sodium propionate and food grade alcohol while the cake without preservative was used as control. The nutritional analysis (proximate analysis and micronutrients) were carried out on preserved and unpreserved cakes. The shelf life of the cake was studied for 15 days. The microbial load was observed at different days (0, 5, 10, and 15). Results: Generally, the preserved cake differ significantly (p<.05) in terms of moisture, crude fibre, carbohydrate and energy content from the unpreserved cake. The unpreserved cake had higher vitamin contents. There was reduced spoilage rate on the treated samples than untreated sample at ambient temperature. The total viable count of the cake without preservative increased from 2.8x102-2.0x106 cfu/g while cakes with preservatives increased from 2.4x102- 5.0x104, 2.0x102- 4.1x102 and 2.0x102- 1.5x104 cfu/g for sodium bicarbonate, alcohol and sodium propionate after 15days at ambient temperature. Conclusion: It is obvious that preservatives though very effectives in lowering cake spoilage and maintaining it quality have nutritional effect on the cake.
Aims: This study addresses the issue of diversification of dankuwa in order to increase its nutritional quality and to determine the nutritional and microbial load of dankuwa sold by vendors and laboratory produced dankuwa. Study Design: To produce dankuwa using other cereal such as millet and sorghum and to determine the nutritional content, sensory properties and microbial load of commercial dankuwa and laboratory produced dankuwa. Place and Duration of Study: Samples were purchased from vendors in Bida Local Government, Nigeria. Analyze at Central Services Laboratory of National Cereal Research Institute, Badeggi, Niger State. Experiment was conducted between November 2013 and March 2014. Methodology: In this study, three samples of dankuwa cereal were used. Two samples were laboratory processed using sorghum or millet and the third sample was purchased from vendors. The various dankuwa samples were analysed to determine their nutritional quality, sensory properties and microbial properties at Central Services Laboratory of National Cereal Research Institute Badeggi, Bida Niger State. Results obtained were subjected to statistical analysis. Results: The proximate content of the dankuwa was evaluated in this study revealed that the crude fat (20.38%) of the locally produced dankuwa (maize + groundnut) did not differ (p>.05) from the laboratory produced dankuwa using millet + groundnut (20.38%). Generally, the dankuwa produced locally differed significantly (p<.05) from those produced using millet and sorghum in appearance, sweetness and overall acceptability as well as their microbial load. The microorganisms isolated from the products were Staphylococcus aureus, Bacillusspp, E. coli, Pseudomonas spp, Micrococcus spp, Aspergillus niger, Aspergillus flavus, Mucor spp, Rhizopus spp, Rhizopus spp and Penicillum spp. Conclusion: The use of other cereal such as sorghum and millet increases the crude protein content of dankuwa as well as attract overall acceptability or preference by panellists.
The chemical analyses of the vegetables; Abelmoschus esculentus, Ceiba pentandra, Cissus populnea andCorchorus oliterious were investigated to evaluate their nutritional potentials. The edible parts of the fresh and dried vegetables were pretreated and analysed for moisture, ash, crude; fibre, fat and protein as well as carbohydrate content while their energy values were estimated using standard methods. In addition, the mineral content was also evaluated using Atomic Absorption Spectrophotometric technique. The result indicated the following range for nutrients in fresh samples; moisture content (86.0to 67.97)%; ash content (2.58 to 0.74)%; crude fibre (15.60 to 2.17)%; crude protein: (0.01 to 0.39)% and carbohydrate (2.53 to 20.90) %. For dried samples the nutrient content in the same order ranges from (17.83 t0 10.39)%; (11.44 to 15.60)%; (39.95 to 25.54)%; (0.04 to 1.37)% and (30.84 to 53.71)% respectively. The energy values ranges from (46.2 to 325.5) kJ/100g and (531.9 to 864.4) kJ/100g in fresh and dried samples respectively. Magnesium was the predominant mineral element among those evaluated while Mn, Ni, Cd, Pb, Zn and Cu were found to be present in relatively low amounts with no clear trend. The wild vegetables were found to be of good nutritional quality having met most of the requirements of regulatory agencies. The values obtained in this study are also in agreement with other studies on vegetables and thus can serve as a source of nutrition therapy for people with certain ailments.