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Kuala Selangor, Malaysia

Viyachai T.,University Putra Malaysia | Abdullah T.L.,University Putra Malaysia | Hassan S.,University Putra Malaysia | Kamarulzaman N.,Serdang | Wan Yusof W.A.,Agro Technology Park
American-Eurasian Journal of Sustainable Agriculture | Year: 2014

The influence of plant density on the growthand flowering of cut chrysanthemum in soilless culture under root restricted condition was investigated. Two varieties of cut chrysanthemum "New White" and "New Yellow" were grown in seedling tray in coconut peat media. Plants were arrangedat three different plant densities namely 64, 81 and 99 plants m2. There were no significant differences for leaf area, leaf length, number of internode and stem diameter between the three plant densities. However, "New Yellow" had significantly more number of inter nodes than "New White".Plant density affected to leaf area index (LAI) and pedicel length. Plants grown at 81 plants m-2had higher LAI of 2.76 than at 64 plants m-2 of 2.28.Pedicel length of plant density of 99 plants m-2 was longer than of 64 plants m-2by 18.33%. There was interaction effect between variety and plant density on number of leaf. Number of leaf tended to decrease when plant densities increase for varieties "New White". No significant differences were observed between the two varieties and three plant densities on root length, root surface area, root diameter, root volume and root shoot ratio. Chlorophyll a, chlorophyll b and total chlorophyll were not significantly affected by varieties and plant densities. Stem fresh weight and total dry weight did not differ between the three plant densities. Plant densities did not significantly affect to photosynthesis, transpiration, stomatal conductance, Fv/Fm. Accumulation of proline was not significant difference between the three plant densities. Chrysanthemum grown at 99 m-2had the tallest plant of 61.28 cm although it was not significantly different from the other two plant densities. Plant densities did not significantly affect to dayto flowering, number of flowers, flower diameter, inflorescence diameter,flowercolor and vase life. These results indicated that under root restriction, chrysanthemum can be grown up to99 plants m2. © 2014 AENSI PUBLISHER All rights reserved. Source

Pendashteh A.R.,Serdang | Fakhru'l-Razi A.,Serdang | Fakhru'l-Razi A.,University Putra Malaysia | Madaeni S.S.,Razi University | And 3 more authors.
Chemical Engineering Journal | Year: 2011

This study focused on the characterization of fouling cake layer during operation of a membrane bioreactor system employed for the treatment of synthetic hypersaline oily wastewater. Also the effects of ultrasound and addition of four types of flocculants (aluminium sulfate, Chitosan, ferric chloride, polyaluminium chloride) on mitigation of membrane fouling were studied. The components of the foulants were examined by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray (EDX) analysis, inductively coupled plasma (ICP) and particle size analyzer (PSA). The FTIR demonstrated that membrane fouling layer is governed by the deposition of organic and inorganic substances composed of extracellular polymeric substances (EPS) (proteins, polysaccharides, etc.), hydrocarbon components and inorganic matters. The AFM images of the fouled membrane confirmed the idea of surface coverage as a fouling mechanism. The SEM analysis showed that rod-shape bacterial clusters were one of the contributors to membrane cake layer. The EDX and ICP results showed that Mg, Al, Ca, Na, K and Fe were the major metal elements in the fouling cake. The PSA results indicate that membrane foulants had a much smaller size than mixed liquor suspensions in the MSBR. Fouling mitigation experiments showed that the effect of organic flocculant was more than inorganic chemicals but the overall effects were not significant. Ultrasound could effectively remove the fouling cake from the membrane surface and thus recovered the membrane permeation flux for a long time. © 2010 Elsevier B.V. Source

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