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The CYN degradation kinetics of each bacterial species were studied using High Performance Liquid Chromatography. The greatest CYN degradation (28.22 ± 0.24%) was shown by the bacterium B. cereus-S in 5.0 mg/L CYN within 14 days. The CYN degradation by the other strains was lower than 10% under the same conditions. Further studies employing different initial concentrations of CYN revealed that B. cereus-S could degrade lower CYN concentrations at a higher percentage (1.0 mg/L, 2.5 mg/L, and 5.0 mg/L of CYN removal percentages were 36.83 ± 2.43%, 32.25 ± 1.25%, and 24.72 ± 0.40%, respectively, after 14 days of incubation at 28℃ and pH 7). The maximum average degradation rates were recorded for 1.0 mg/L, 2.5 mg/L, and 5.0 mg/L CYN on the 6th (0.05 ± 0.00 mg/L/day), 8th (0.04 ± 0.01 mg/L/day), and 12th (0.02 ± 0.01 mg/L/day) days of incubation, respectively. The study showed the potentiality of the bacterium B. cereus-S on the application for degrading CYN among the tested bacteria species. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) is the staple food in Sri Lanka and phosphorus (P) and potassium (K) are major nutrients for the rice plant. However, the variation of P and K contents (mg kg-1) in rice soils and rice grains as affected by agro-climatic zones (ACZs), water source used (i.e., major irrigation, minor irrigation and rain-fed) and cropping systems adopted (i.e., fallow, vegetable, perennials, other field crops) by Sri Lankan farmers are not well elucidated, and are thus investigated in the present study. A total of 200 rice soil and 230 rice grain samples across the country were collected from farmer fields, representing different ACZs, water sources used, and cropping systems adopted using a stratified random sampling approach. The total and available P and K contents in rice soil, and the P and K contents in rice grains were determined. The plant-available P contents in soil were similar among ACZs, water sources, and rice-based cropping systems. Exchangeable K content was higher in rice fields where vegetables were cultivated in the previous season. Grain P and K contents were similar among the water sources used and rice-based cropping systems. Grain P contents was the lowest in the Low country Wet zone. Soil available-P and total-P contents (r = 0.29, p < 0.0001), and grain P and K contents were positively correlated (r = 0.51, p < 0.0001). The knowledge generated in the present study is important in P and K nutrient management in rice cultivation in the country. [ABSTRACT FROM AUTHOR]

The transportation problem (TP) is a significant factor in operational research. Numerous researchers have put forth various solutions to these problems. The goal is to reduce the overall cost of distributing resources from multiple sources to numerous destinations. If there are road risks (snow, flood, etc.), traffic limitations, etc., it might not be feasible to transport products from one place to another. In these circumstances, the appropriate route(s) can be given an extremely high unit cost, such as M (or ∞). Following that, a specific case of the prohibited transportation problem is introduced. Therefore, the focus of this study is to provide a novel algorithm that will reduce the cost of restricted transportation problems. With a few modifications, the traditional Vogel approach has been enhanced. The proposed method would perform better than the other approaches now in use. The numerical problem is resolved to demonstrate the effectiveness of the proposed approach and make comparisons with different approaches already in use. [ABSTRACT FROM AUTHOR]

Heat pump drying systems require a method to change the inflow air temperature of the drying chamber. Pulse-widthmodulation (PWM) technique with duty cycle provides a measure of controlling the voltage supplied to the electric motors. Therefore, we conducted this research to PWM control a heat pump dryer to change the air circuit parameters. In the Parallel-Flow condensers, inlet and outlet temperatures, and relative humidity, data were collected, and the average temperature values were recorded. The duty cycle was changed by developing a program using the Python programming language. An Excel-based psychrometric calculator was developed to analyze the collected data. The average condenser outlet temperatures were 56.6±0.1 °C, 54.9±0.1 °C, and 52.6±0.1°C, and the average condenser inlet temperatures were 43.2±0.0 °C, 42.8±0.1 °C, and 41.2±0.1 °C for 60%, 80%, and 100% duty cycles, respectively. The power consumption rate of the condenser reduced with an increasing duty cycle. The results concluded that the PWM control system is a viable method to control the inflow air temperature to the drying chamber. [ABSTRACT FROM AUTHOR]

Various environmental, economic and health problems have arisen in the world due to the continuous application of N-fertilisers for crop production, especially in the third world countries. The current study was undertaken to develop effective rhizobial inoculants for three major legume crops in Sri Lanka, namely Vigna mungo, Vigna radiata and Glycine max to replace the application of nitrogen fertilisers. Rhizobial isolates were obtained from the root nodules of different cultivars of edible legumes, non-edible wild legumes and wild relatives of Vigna spp. Authentication and screening for effectiveness of the isolates were carried out, and five strains were selected as effective isolates and cross inoculated with the three legumes along with a stress tolerant strain, which was previously screened. A pot experiment was followed by a field trial in the dry zone of Sri Lanka under farmers' conditions as single and multi-strain inoculations. The results of the pot experiment indicated that the addition of rhizobial inoculants increased the growth performance in all treatments. In the field trial, both single and multi-strain inoculants gave significant increases in yield, compared to N-fertiliser application in all three crops, viz; an increase of the yield from 3 % to 39 % in V. mungo, 5 % to 14 % in V. radiata, and 4 % to 13 % in G. max. In conclusion, the current study has shown that single and multi-strain rhizobial inoculants are capable of completely replacing urea application to V. mungo, V. radiata and G. max, in Sri Lanka without any yield reduction. [ABSTRACT FROM AUTHOR]

Mineral detection using remote sensing techniques is important since it saves the time and effort of carrying out manual land surveys. In this paper a novel algorithm, which can be used to detect ilmenite using hyperspectral image analysis is discussed. To investigate this task, a hyperspectral image obtained from the Earth Observing-1 (EO-1) satellite's Hyperion sensor was used. In the proposed algorithm, first, principal component analysis (PCA) was used for dimensionality reduction and an Euclidean distancebased method was used to extract the pixels containing soil. Thereafter, lab spectral data of typical ilmenite deposits were considered as the reference and a correlation factor analysis was carried out to determine the soil pixels, which are most likely to contain ilmenite and most unlikely to contain ilmenite. Using these two sets of pixels, a training set was constructed to apply Fisher's discriminant analysis (FDA) in order to separate the dataset into two distinct classes - ilmenite and non-ilmenite. Based on the spectral similarity, each pixel of the image was classified under one of these classes. This paper also introduces a probability-based approach to obtain results that are more accurate. A probability density function was designed considering the spatial distribution of the mineral. Thereafter, classification was done considering the probability measure as well. Lab tests performed on the soil samples collected from the locations, which were detected by the algorithm validate that the algorithm is accurate. [ABSTRACT FROM AUTHOR]