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281.
In order to observe the variation in land use changes, satellite images from the Landsat Thematic Mapper (TM) and the Enhanced Thematic Mapper (ETM) for 1991, 2000, 2005, and 2008 were used to compare the differences between selected water quality parameters, including heavy metal (Cd, Pb, and Zn) content in both water and green mussels or Perna viridis (Linnaeus.) before and after the increase in land use activities beginning from 2006. The samples were collected at 11 points for water and 4 points for green mussels between the Second Link and the Causeway Link at the Johor Strait in 2009 and were analyzed for pH, temperature degrees Celsius), dissolved oxygen, ammoniacal nitrogen, and heavy metal (Cd, Pb, and Zn) content.  相似文献   
282.
The adsorption of residue oil from palm oil mill effluent using natural zeolite was investigated in this study. The adsorption was performed in batch mode, and the effect of different operational parameters such as pH, dose of adsorbent, stirring rate, contact time and initial oil concentration were explored. It was found that the pH plays a major role in the adsorption process. Isotherm data best fitted with the Freundlich model, and kinetic data followed the pseudo-second-order kinetic model. The results obtained demonstrated that the oil removal efficiencies by natural zeolite were up to 70?% at a pH of 3.0 and 50?min of contact time. The adsorbent material also has been characterised by X-ray diffraction, X-ray fluorescence and scanning electron microscopy.  相似文献   
283.
Eryngium bornmuelleri Nab. (Tusî) is an endemic botanical from the Eastern Anatolia region of Turkey traditionally used for preparation of herbal tea. Within this study, phenolic composition, antioxidant capacities and inhibitory activities towards selected digestive enzymes of E. bornmuelleri leaf were investigated. Sequential extracts, obtained by extraction of plant tissue by ethanol, acetone and water exhibited pronounced antioxidant capacities and in a dose-dependent manner suppressed the metabolic syndrome related enzymes: α-amylase, α-glucosidase and pancreatic lipase. All extracts contained high levels of phenolic compounds. Flavonoid glycosides were the main phytochemicals detected, with rutin as the major compound (70 % of total phenolics). Chlorogenic, hydroxybenzoic and caftaric acids as well as traces of caffeic, ferulic and rosmarinic acids were also detected. Correlation analysis indicated that phenolic compounds were the major sources of the enzyme-inhibitory activities. This study suggests that E. bornmuelleri leaf extracts can modulate the metabolism of sugars and fats through inhibition of the relevant digestive enzymes.  相似文献   
284.
This paper presents an investigation of the influences causing failure in the materials comprising polymer matrix composites. Structures with differences in stacking sequences and design configuration are analysed. The objective of this study is to investigate and evaluate the reasons for the failure of composite lamination structures in terms of stress, strength, strain, and Young modulus within a morphology observation of composite materials. The materials selected for the study were a chopped strand mat (CSM) and a woven roving (WR) fabric. These materials are used as reinforcement and are produced by the hand lay-up technique using epoxy and polyester matrix resin. The experiment was performed using specimens made of notched (open-hole; OH) tension and un-notched (UN) shapes. The characteristics of different shapes, materials, and lamination structures are studied in this research. The results showed the failure phenomenon in the structure of the polymer matrix composite is dependent on the characteristics of the material used and the design configuration of both structures.  相似文献   
285.
The study estimates technical efficiency and investigates the factors affecting the technical inefficiency of cage fish farming in Peninsular Malaysia. The study employs the stochastic frontier function to estimate a production frontier and technical inefficiency model. The data were collected using standard structured questionnaires completed by sample cage fish farmers in the study area. The result reveals an estimated mean technical efficiency score of 0.79, implying that the sample fish farmers are operating 21% below the production frontier and thus, there is room for improvement. The production function involves the use of one output and four inputs, which are stocking density, feed, labour and other relevant production costs. The coefficients of all the inputs have positive signs and statistically significant impacts on the output. The output elasticity associated with stocking density is the highest (0.634), followed by feed (0.317). The null hypotheses that the technical inefficiency effects are absent from the model and that the combined exogenous variables do not influence inefficiency are strongly rejected. The individual's null hypotheses of no age effect, no experience effect, no education effect, no species effect, no extension services effect, no workshop attended effect and no diseases effect on technical inefficiency are all rejected at different levels of statistical significance.  相似文献   
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