Effects of Regulated Deficit Irrigation on Growth of Sorghum Cultivar

The  effects of  regulated deficit irrigation technique on growth of sorghum was examined in a greenhouse at the Faculty of Agrotechnology and Food Science Research Farm, University Malaysia Terengganu. The experiments regulated deficit irrigation (RDI) consisted of a factorial combination of irrigation regimes and soil types laid in a randomised complete block design with eight treatments for each experiment which resulted into a total of sixteen treatments. Irrigation regimes were at four levels namely: I100, I75, I50 and I25 and the soil types were at two levels namely: Rhu Tapai and Rengam soil Series. The treatments were randomly assigned to experimental pots and replicated four times. A total of thirty two pots were used for the study. All agronomic practices starting from land preparation to harvesting were adhered to and growth parameters were recorded for the experiment. The result of the study shows that, sorghum performance improved under regulated deficit irrigation techniques. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of growth parameters, crop water use efficiency, under Regulated deficit irrigation and compared to I50 and I25 irrigation regimes. The study also revealed that there were interaction effects of deficit irrigation and the two types of soil on some of the parameters used for the study. The study, therefore, recommended the use of I75, for optimizing sorghum growth in this agro ecological zone. Key words: Regulated deficit irrigation, Growth. Water use efficiency, Rhu Tapai soil series, Rengam soil serie

Sol-Gel (3-Mercaptopropyl)Trimethoxysilane-Methyltrimethoxysilane as adsorbent for stir bar Sorptive extraction of selected organic dyes

A new sol-gel hybrid silica-based (3-mercaptopropyl)trimethoxysilane-methyltrimethoxysilane (MPTMOS-MTMOS) in the ratio of 3:1 was synthesized and applied as an adsorbent in stir bar sorptive extraction (SBSE) of three selected polar organic dyes from water sample. Three organic dyes were used as test analytes namely crystal violet, methyl orange and methylene blue. Analysis of the organic dyes was performed using ultravioletvisible spectroscopy. Optimum extraction conditions was achieved using 50 min extraction time, 240 rpm stirring rate, ultrasonic aided desorption for 15 min using 3 mL methanol and sample solution at pH 4 with addition of 5% (w/v) NaCl. The sol-gel hybrid MPTMOS-MTMOS showed better extraction efficiency (based on absorbance) for the selected organic dyes compared to commercial ethylene-glycol/silicone Twister™ stir bar. Limit of detection obtained was in the range 0.34 -0.75 μg mL-1 (S/N = 3) and linear range achieved was 10 order of magnitude (1.0-10 μg mL-1). The developed sol-gel hybrid material showed high potential as an alternative adsorbent for SBSE of organic dyes. MPTMOS-MTMOS SBSE was successfully applied for simultaneous analysis of three organic dyes from river water with good recovery

Effect of Partial Rootzone Drying Technique on Yield and Yield Components of Sorghum Cultivar

A greenhouse experiments was conducted at Faculty of Agrotechnology and Food Science Research Farm, Universiti Malaysia Terengganu to evaluate the effects of partial rootzone drying (PRD) techniques on yield and yield components of sorghum planted on two series of soil. Partial root zone drying (PRD) consisted of a four irrigation regimes namely Full irrigation (I100), 75% (I75), 50% (I50) and 25% (I25) and the two types of soil are Rhu Tapai Soil Series and Rengam soil Series. The experiment was laid out in a randomized complete block design with eight treatments. The treatments were randomly assigned to experimental polythenebags and replicated four times. A total of thirty two polythenebags were used for the study. All agronomic practices starting from preparation to harvesting were adhered to and yield parameters were recorded for the experiment. The result of the study shows that, sorghum performed better under the PRD technique. The results further revealed that, irrigation regimes I100 and I75 performed better in terms of yield and yield components, crop water use efficiency, under PRD compared to I50 and I25 irrigation regimes. The study also revealed that there were interaction effects of deficit irrigation and the two types of soil on some of the parameters such as harvest index and number of panicle used for the study. The benefit-cost ratio of sorghum production under I100 and I75 irrigation regimes were found to be economically better compared to I50 and I25 irrigation regimes for PRDI. The study, therefore, recommended the use of PRDI for optimizing sorghum production in the semi arid regions.

Magnetic graphene oxide as adsorbent for the removal of lead(II) from water samples

Magnetic Fe3O4 nanoparticles were prepared on graphene oxide (Fe3O4/GO) in situ in a one step process. The obtained Fe3O4/GO was used as an adsorbent for the removal for Pb(II) from environmental water samples prior to flame atomic absorption spectroscopy measurement. The adsorption procedure was optimized as follows: 60 min adsorption time, 50 mL sample volume, solution pH 4.5, and 25 mg adsorbent dosage. Under the optimum conditions, the adsorption efficiency obtained was greater than 75% (C = 50 mg L-1). The adsorption isotherm of Fe3O4@GO magnetic adsorbent was studied for Pb(II) adsorption using two isotherm adsorption models namely Langmuir and Freundlich. The adsorption isotherm data fits well with Langmuir isotherm (R2 = 0.9988) rather than with Freundlich isotherm. The maximum adsorption capacity (qm) obtained was 86.2 mg g-1. The results signified that the prepared Fe3O4/GO nanocomposite has a great adsorptive ability towards the Pb(II) from environmental water samples

Rapid Determination of Non-steroidal Anti-inflammatory Drugs in Aquatic Matrices by Two-phase Micro-electrodriven Membrane Extraction Combined with Liquid Chromatography

Two-phase micro-electrodriven membrane extraction (EME) procedure for the pre-concentration of selected non-steroidal anti-inflammatory drugs (NSAIDs) in aquatic matrices was investigated. Agarose film was used as interface between donor and acceptor phase in EME which allowed for selective extraction of the analytes prior to high performance liquid chromatography-ultraviolet detection. Charged analytes were transported from basic aqueous sample solution through agarose film into 1-octanol as an acceptor phase at 9 V potential. Response surface methodology in conjunction with the central composite design showed good correlations between extraction time and applied voltage (R 2 > 0.9358). Under optimized extraction conditions, the method showed good linearity in the concentration range of 0.5-500 μg L -1 with coefficients of determination, r 2 ≥ 0.9942 and good limits of detection (0.14-0.42 μg L -1) and limits of quantification (0.52-1.21 μg L -1). The results also showed high enrichment factors (62-86) and good relative recoveries (72-114%) with acceptable reproducibilities (RSDs ≤ 7.5% n = 3). The method was successfully applied to the determination of NSAIDs from tap water and river water samples. The proposed method proved to be rapid, simple and requires low voltage and minute amounts of organic solvent, thus environmentally friendly

Magnetic graphene sol-gel hybrid as clean-up adsorbent for acrylamide analysis in food samples prior to GC-MS

Graphene (G) modified with magnetite (Fe3O4) and sol–gel hybrid tetraethoxysilane-methyltrimethoxysilane (TEOS-MTMOS) was used as a clean-up adsorbent in magnetic solid phase extraction (MSPE) for direct determination of acrylamide in various food samples prior to gas chromatography-mass spectrometry analysis. Good linearity (R2 = 0.9990) was achieved for all samples using matrix-matched calibration. The limit of detection (LOD = 3 × SD/m) obtained was 0.061–2.89 µg kg-1 for the studied food samples. Native acrylamide was found to be highest in fried potato with bright-fleshed (900.81 µg kg-1) and lowest in toasted bread (5.02 µg kg-1). High acrylamide relative recovery (RR = 82.7–105.2%) of acrylamide was obtained for spiked (5 and 50 µg kg-1) food samples. The Fe3O4@G-TEOS-MTMOS is reusable up to 7 times as a clean-up adsorbent with good recovery (>85%). The presence of native acrylamide was confirmed by mass analysis at m/z = 71 ([C3H5NO]+) and m/z = 55 ([C3H3O]+)

Provenance Establishment of Stingless Bee Honey Using Multi-element Analysis in Combination with Chemometrics Techniques

As consumption of stingless bee honey has been gaining popularity in many countries including Malaysia, ability to identify accurately its geographical origin proves pertinent for investigating fraudulent activities for consumer protection. Because a chemical signature can be location-specific, multi-element distribution patterns may prove useful for provenancing such product. Using the inductively coupled-plasma optical emission spectrometer as well as principal component analysis (PCA) and linear discriminant analysis (LDA), the distributions of multi-elements in stingless bee honey collected at four different geographical locations (North, West, East, and South) in Johor, Malaysia, were investigated. While cross-validation using PCA demonstrated 87.0% correct classification rate, the same was improved (96.2%) with the use of LDA, indicating that discrimination was possible for the different geographical regions. Therefore, utilization of multi-element analysis coupled with chemometrics techniques for assigning the provenance of stingless bee honeys for forensic applications is supported

Sol–gel coated polypropylene hollow fiber-based liquid-phase microextraction of triazine herbicides in real water samples

A sol–gel coated hollow fiber-based liquid-phase microextraction (LPME) method was developed for the extraction of triazine herbicides. The polypropylene hollow fiber was coated with polydimethylsiloxane–divinylbenzene using sol–gel method and characterized. The developed method was compared with uncoated hollow fiber LPME method for the extraction of simazine, atrazine, and propazine prior to gas chromatography–mass spectrometry analysis. Optimized conditions for both coated and uncoated hollow fibers LPME methods were toluene as an acceptor phase, length of hollow fiber (1.5 cm), volume of acceptor phase (3.0 µL), stirring rate (1200 rpm), and no addition of salt (sodium chloride). The optimized volumes of donor phase for uncoated fiber and coated fiber were 4.0 and 4.5 mL, respectively, while the optimized extraction times were 30 min for uncoated hollow fiber and 10 min for coated hollow fiber. The developed sol–gel coated hollow fiber LPME method provided good enrichment factors (EFs) ranging from 100 to 139, good recoveries (75.27–104.47%), and good reproducibility (relative standard deviations [RSDs] < 0.83%). Meanwhile, uncoated hollow fiber LPME method showed lower EFs ranging from 80 to 90 and relatively low recoveries of 60.72–68.17%, whereas it has good reproducibility with RSDs < 0.94%. The proposed method was successfully applied to the analysis of real water samples and the analyte recoveries for spiked water samples was in the range of 42.54–78.75%

Applicability and usability of predefined natural language boilerplates in documenting requirements

Natural language is frequently applied to document the stakeholders’ statements during requirement elicitation activities. Nevertheless, the use of generic natural language has potential for the issues of unclear and inconsistent requirements. These issues may result from the diverse interpretations by the stakeholders or other various sources of documents and artefacts. The main objective of this paper was to discuss the definition and application of predefined boilerplates to specify the requirements in the form of natural language statements. The proposed boilerplates were defined and classified based on two main types of requirements, namely functional and non-functional (performance, constraints, and specific quality). Two methods have been applied to evaluate the research results; the applicability of the predefined boilerplates was demonstrated using two different case studies, and the usability aspect is evaluated through synthetic environment experimentation using human respondents. As a summary, the predefined boilerplates were found helpful, especially among novice requirement engineers to express and specify their requirements in a consistent manner and a standardized way, relatively able to improve the quality of the natural language statements

Understanding pore formation and structural deformation in carbon spheres during KOH activation

Carbon spheres (CSs) were synthesized from sucrose by hydrothermal reaction. The synthesized materials were further activated with potassium hydroxide (KOH) at different concentrations. The effects of KOH concentration on the surface area and morphology were investigated. The route for pore formation and structural deformation in carbon spheres during activation has been proposed and discussed based on micrographs and porosity trends. It was suggested that the pore formation and structural deformation phenomena were due to the intercalating power of energized K+ into the carbon. This work provides an insight of the pore formation in carbon spheres for the development of adsorbents as well as for the understanding of the structural deformation of such materials at higher KOH concentrations