2,179 research outputs found

    Removal of mercury (II) from aqueous solution by using rice residues

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    Sorption potential of rice residues for Hg(II) removal from aqueous solution was investigated. Rice husk (RH) and rice straw (RS) were selected and treated with sodium hydroxide (NaOH). The raw and modified adsorbents were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and BET surface area measurements. The effects of pH, initial ion concentration, and agitation time on the removal process were studied in batch adsorption experiments. Two simple kinetic models, which are pseudo-first-order and pseudo-second-order, were tested to investigate the adsorption mechanisms. The kinetic data fits to pseudo second order model with correlation coefficients greater than 0.99 for all adsorbents. The equilibrium data fitted well with the Langmuir compared to Freundlich isotherm models. Alkali-treated adsorbent obtained larger surface area and RH-NaOH showed highest adsorption capacity followed by RS-Pure > RH-Pure > RS-NaOH. The maximum removal efficiency obtained by RH-NaOH and RS-Pure was 42 mg/l (80%) at pH 6.5 and with 2 days contact time (for 50 mg/l initial concentration and 25 mg adsorbents)

    Fluorescent Lamp Light Intensity on the Embryogenesis Development and the Survival of Pearl Oyster (Pinctada Maxima) Larvae

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    One of the important factors in determining the success of pearl oyster (Pinctada maxima) culture is the quality and quantity of larvae produced in brood stock spawning process in the laboratory. Problems were often found in larval rearing and larvae attachment to the substrate that were low in quality and little number of larvae. The study purposes were observe the embryogenesis development and the survival rate of pearl oyster larvae under different fluorescent lamp light intensities. The study was conducted in August 1nd – 30th, 2011 in Sambelia Bumi Gemilang Hamparan Mutiara laboratory, East Lombok. Results revealed that different in light intensities effected the survivorship of the pearl oyster larvae significantly (p<0.01). Honest Significant Difference (HSD) test indicated that the highest survival rate occurred in dark condition (dark treatment) of 38%, followed by intensity of 10 watts (34.67%), 5 watts (30.67%) and 15 watts (4.66%) resfectivel

    Settlement Ability of Pearl Oyster (Pinctada Maxima) Larvae at Different Positions and Depths Collectors

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    One of the success factor in the cultivation of pearl oysters (Pinctada maxima) within laboratory scale of is the ability of the larvae to settle on the collector. Stocking collectors which are not on time with an irregular position could cause a decline in seed production. The research was conducted from 25 July to 27August 2011 at Laboratory of Marine Bio-industry Technical Implementatation Unit, Research Centre for Oceanography, Indonesian Institute of Sciences, Lombok, West Nusa Tenggara (NTB). The aim of the study was to observe the attachment of larvae at different position and depth. Analysis of variance showed that larvae settlement was influenced by depth instead of position and the interaction between them. Real Honest Different Test showed that in the 20 cm depth was significantly different from 60 cm and 100 cm in number of larvae attached on the collector. The highest survival rate was in 20 cm depth with 68,98% (516 larvae) while in 60 cm was 17,11% (128 larvae) and 100 cm (9,22% (69 larvae), and the others were attached on the wall of the tank 4,68% (35 larvae)

    Factors influencing purchase intention of organic meat among consumers in Klang Valley, Malaysia

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    Multitude of factors such as concern for use of growth hormones, chemical additives in feed, animal welfare, human health issues and environmental impacts have led to the steady increase in the consumption of organic meat worldwide. The purpose of the study was to investigate the factors that influence the purchase intention towards organic meat based on the Theory of Planned Behavior (TPB) and organic meat choice motives. The influence of attitude, subjective norm, perceived behavioral control, safety, meat characteristic, health concern and price on the intention to purchase organic meat was analyzed. The study utilized cross-sectional research design using survey method. A total of 400 consumers responded to the survey using mall-intercept, with both genders equally represented and had an average age of 35 years. Results showed that the respondents seemed to be very concern about food safety (m=4.06) and meat characteristics (m=4.04) as compared to health (m=3.70) and price (m=3.36) was not a strong motivating factor (m=3.35). The level of attitude towards organic meat, subjective norm and perceived behavioral control was at moderate level. The findings showed that perceived behavioral control and personal norm towards organic meat of TPB and price and meat characteristic of the choice motives could explain 66.4 percent of the variance in the intention to purchase organic meat. As intention to purchase is an important indicator of future organic meat consumption, policy makers and marketers may draw on these results when attempting to promote and enhance acceptance of organic meat among the consumers

    Sedimentation Rate and Dispersion of Organic Waste From Lobster Culture on Cage in Ekas Bay, West Nusa Tenggara Province

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    The objective of this study was to determine sedimentation rate and dispersion of organic waste from lobster culture on cage in Ekas Bay, West Nusa Tenggara Province. Measurement of sedimentation rate was conducted every month during the process of cultivation lobster. This measurement was done by setting up a sediment trap under and around the cage. The result of this study showed that sedimentation rate under the lobster cage within 270 days ranged from 14.92 to 27.33 (20.66±4.60) g/m2/day. The organic waste did not disperse far away from the cage because of the small current rate around the cage location of 0.068 to 0.2 m/s. Feces and residual feed settling velocities followed the current direction within the range of 0.0373 to 0.072 m/s with 8.50 m of water depth. According to this result, dispersion of feces particle and residual food was between 8.24 and 45.58 m from the cage. In order to prevent an accumulation of waste particle on the water bottom, the distance between cages needs to be set to at least twice of the farthest distance of particle dispersion which is 2 x 45.58 = 91.16 m or about 100 m

    Unravelling Layers of Colonial and Post-Colonial Open Space Planning and Heritage: The Identity of [Padang] Merdeka Square, Kuala Lumpur, Malaysia

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    In 1880, when the British moved their Federated Malay States administrative centre to Kuala Lumpur, the Padang quickly became a symbol of British economic and administrative colonisation, and a nucleus of the socio-cultural development of Kuala Lumpur. This paper discusses the layers of history, symbolism and cultural values that the Padang contributes to the socio-cultural tapestry of both Kuala Lumpur and Malaysia, and the lack of relevant planning and heritage measures to conserve these attributes and characteristics. The conclusions offer avenues to engage with pre- and post-colonisation that enable re-making and the conservation of the iconic space of Kuala Lumpur.Keywords: Urban open space; Merdeka Square; Kuala Lumpur City Hall; National Heritage Act 2005eISSN: 2398-4287 © 2019. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.DOI: https://doi.org/10.21834/e-bpj.v4i11.1721             
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