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This research work deals with the sensitivity investigation of N similar evacuated tubular collectors (N-ETCs) having series connection taking computer codes inscribed in MATLAB-2015a considering a normal day of May for New Delhi ...
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This research work deals with the sensitivity investigation of N similar evacuated tubular collectors (N-ETCs) having series connection taking computer codes inscribed in MATLAB-2015a considering a normal day of May for New Delhi complex climate. The sensitivity with respect to N for N-ETCs from exergy as well as heat gain viewpoints is maximum with mean sensitivity figure values as 0.92 and 2.11 respectively. This analysis will help the designer to focus on particular input parameter as per the requirement of user.
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摘要 :AbstractPhenol is an important pollutant widely discharged as a component of hydrocarbon fuels, but its degradation in cold regions is a great challenge due to the harsh environmental conditions. To date, there is little informati...
展开AbstractPhenol is an important pollutant widely discharged as a component of hydrocarbon fuels, but its degradation in cold regions is a great challenge due to the harsh environmental conditions. To date, there is little information available concerning the biodegradation of phenol by indigenous Antarctic bacteria. This study addresses the isolation of three phenol-degrading bacterial strains from King George Island, Antarctica. Based on preliminary screening, three isolates (AQ5-05, AQ5-06 and AQ5-07) capable of completely degrading 0.5 g/L phenol within 120 h at 10 °C were selected for detailed study. Two were identified asArthrobacterspp., and oneRhodococcussp., based on 16S rRNA sequences. All strains were non-motile, Gram positive, oxidase negative and catalase positive. A study on the effects of parameters including temperature, pH, salinity and nitrogen source was conducted to optimise the conditions for phenol degradation. This revealed that the three isolates were psychrotolerant with the optimum temperature for phenol degradation between 10 and 15 °C. This study suggests the potential use of cold-adapted bacteria in the bioremediation of phenol over a wide range of low temperatures.收起
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Lignocellulosic biomass (LSB) is the most abundantly available renewable source in the world. Rice husk (RH) is also one of the LSB. In this study, the optimization of dilute acid hydrolysis conditions of RH by using one-factor-at...
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Lignocellulosic biomass (LSB) is the most abundantly available renewable source in the world. Rice husk (RH) is also one of the LSB. In this study, the optimization of dilute acid hydrolysis conditions of RH by using one-factor-at-a-time method was performed. The optimum hydrolysis conditions of RH were determined as 131.04 degrees C, 1:10.28 (w/v) of solid:liquid ratio, 1.47% (w/v) of acid ratio and 24.05 min, which yielded as 25.52 g/L of fermentable sugar concentration. Furthermore, the chemical composition of hydrolysate was also examined and the levels of phenolics, 5-hydroxymethylfurfural (HMF), acetate, glucose, and fructose+xylose were found as 0.89, 0, 3.27, 2.10, and 13.80 g/L, respectively. Accordingly, RH can be utilized as a favorable feedstock for the production of value-added products.
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摘要 :
Lipase secretion by halophilic strains under solid state fermentation has been relatively understudied, especially when utilizing agro-industrial substrates. Eleven halophilic bacterial strains were locally isolated and screened f...
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Lipase secretion by halophilic strains under solid state fermentation has been relatively understudied, especially when utilizing agro-industrial substrates. Eleven halophilic bacterial strains were locally isolated and screened for lipase secretion. All the strains were subsequently subjected to the screening on various agro-industrial substrates for the lipase production, and to assess the best supporting substrate. The halophilic strain with the maximum lipase secretion (0.264 U/g) potential was selected and identified asBacillus amyloliquefaciensAIKK2. Coconut fibre was found the best supporting substrate for halophilic lipase secretion and influence of nutritional and environmental parameters on halophilic lipase secretion was determined using One-Factor-At-A-Time. The optimized experiment was conducted at 6% glucose, 9% NaCl, 40 °C, and 200 rpm agitation speed resulted in the enhanced lipase secretion (0.29 U/g). Further, halophilic lipase characterization studies revealed that the enzyme was thermally stable at 50 °C, showed the improved activity at moderate NaCl and rare tolerance in hydrophilic solvents.
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Lactococcus lactis?is a?Gram-positive?bacterium widely used in the production ofbuttermilk?and?cheese. Recently, the bacterium becomes famous as the genetically modified organism can be used alive for the treatment of disease. In ...
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Lactococcus lactis?is a?Gram-positive?bacterium widely used in the production ofbuttermilk?and?cheese. Recently, the bacterium becomes famous as the genetically modified organism can be used alive for the treatment of disease. In this study,different cultural conditions based on agitation speed and temperature on the growth of recombinant?L. lactis?NZ9000 harboring domain 1 of aerolysin gene (NHD1Aer) were investigated using shake flask experiment. The effect of different carbon (glucose, sucrose and lactose) and nitrogen (yeast extract, peptone, NH4Cl, (NH4)2SO4, and urea) sources in M17 medium on the cell accumulation were also tested. The results showed that the highest cell concentration (3.22 g/L,?μm?= 0.58 h-1) was obtained when the cultivation was incubated at 27°C and at agitation of 100 rpm. The cells growth was markedly improved when utilizing glucose and peptone/yeast extract as carbon and nitrogen sources, respectively. The aerolysin gene in the cells after four generation time was extracted and then analyzed using agarose gel electrophoresis. The results obtained showed a 250 bp band amplified of domain 1 of the aerolysin gene.
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De nos jours, les modèles mathématiques deviennent très complexes et cette complexité se traduit, généralement, par une multiplication de leurs paramètres d'entrée (inputs). Cependant, ces derniers n'ont pas tous le même ...
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De nos jours, les modèles mathématiques deviennent très complexes et cette complexité se traduit, généralement, par une multiplication de leurs paramètres d'entrée (inputs). Cependant, ces derniers n'ont pas tous le même niveau d'influence sur les sorties (outputs). Dans le but d'identifier les paramètres les plus sensibles d'EPIC, ceux qui peuvent guider l'utilisateur dans la collecte d'informations sur le terrain et dans le processus de calibrage du modèle, une analyse de sensibilité par l'approche One-Factor-At-A-Time (OAT) a été effectuée sur deux jeux de données : l'un provenant du Programme-Action-Hesbaye (PAH, 1996) et l'autre du projet INCO (2000). La méthode utilisée consiste à modifier chaque entrée du modèle par -10 %et +10 % par rapport à sa valeur initiale. L'effet de chaque modification opérée est analysé sur six sorties d'EPIC, notamment : azote lessivé, eau percolée, eau consommée, biomasse, rendement et humus minéralisé dont la sensibilité est signifiée par le calcul d'un indice appelé "Indice de Sensibilité" et par un pourcentage de variation. En effet, les sorties considérées se montrent particulièrement sensibles aux paramètres "Unités de chaleur potentielles" (PHU), "Fraction d'azote dans la plante à 50 % de maturité" (BN2), mais surtout au "Second point de l'évolution de la courbe du LAI" (DLAP2). Une variation de 10 % de ce dernier provoque des changements moyens d'environ 14 % et 85 % sur les six sorties, respectivement pour les jeux de données du PAH et du projet Inco.
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摘要 :
To predict or control the response of a complicated numerical model which involves a large number of input variables but is mainly affected by only a part of variables, it is necessary to screening those active variables. This pap...
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To predict or control the response of a complicated numerical model which involves a large number of input variables but is mainly affected by only a part of variables, it is necessary to screening those active variables. This paper proposes a new space-filling sampling strategy, which is used to screening the parameters based on the Morris' elementary effect method. The beginning points of sampling trajectories are selected by using the maximin principle of Latin Hypercube Sampling method. The remaining points of trajectories are determined by using the one-factor-at-a-time design. Being different from other sampling strategies to determine the sequence of factors randomly in one-factor-at-a-time design, the proposed method formulates the sequence of factors by a deterministic algorithm, which sequentially maximizes the Euclidean distance among sampling trajectories. A new efficient algorithm is proposed to transform the distance maximization problem to a coordinate sorting problem, which saves computational cost much. After the elementary effects are computed using the sampling points, a detailed criterion is presented to select the active factors. Two mathematic examples and an engineering problem are used to validate the proposed sampling method, which demonstrates the priority in computational efficiency, space-filling performance, and screening efficiency.
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Neutral proteases have a large variety of industrial applications. Therefore, the optimization of their production for the large-scale commercial purpose is critical. The present study was aimed to the optimization of nutritional ...
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Neutral proteases have a large variety of industrial applications. Therefore, the optimization of their production for the large-scale commercial purpose is critical. The present study was aimed to the optimization of nutritional and physical conditions affecting neutral protease production of Aeromonas hydrophila MSB16, not previously reported for this genus. Four key determinants (pH, temperature, glucose and peptone concentration), were selected based on the results of the one-factor-at-a-time (OFAT) method and then optimized by the response surface methodology (RSM). Maximum enzyme production (229.72 U/ml) which was 2.3 folds higher than that of the OFAT method (99.25 U/ml) and 3.15 times higher than unoptimized conditions (72.86 U/ml) was observed at 30 °C, pH 7, 4.5% w/v glucose and 4.5%w/v peptone by using a rotatable central composite design (RCCD). The results showed that the OFAT and RSM strategies were a useful screening and optimization methods for enhancing the protease production of the strain MSB16, respectively.
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This paper proposes and evaluates an alternative search procedure to be used within the framework of the Mahalanobis-Taguchi System (MTS). An adaptive One-Factor-At-a-Time (aOFAT) search is employed wherein features are individual...
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This paper proposes and evaluates an alternative search procedure to be used within the framework of the Mahalanobis-Taguchi System (MTS). An adaptive One-Factor-At-a-Time (aOFAT) search is employed wherein features are individually removed or added to a classification system. Features are retained only if they contribute positively to the signal to noise ratio. This alternative search procedure is compared with orthogonal arrays and forward selection by means of two case studies. aOFAT experimentation provided greater improvements on the median with the same or fewer design alternatives being explored and also exhibited good ability to generalise to new instances after training. Two mechanisms related to interaction size and synergy help to explain the large benefits of aOFAT search observed in these case studies.
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摘要 :
Power loss during blackouts shows an increasing complexity with the increase in the size of power grids. Traditional statistical methods based on the assumption of stationarity can lead to inappropriate assessments of blackouts. T...
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Power loss during blackouts shows an increasing complexity with the increase in the size of power grids. Traditional statistical methods based on the assumption of stationarity can lead to inappropriate assessments of blackouts. This study builds on the generalized extreme value (GEV) distribution by introducing time as a covariate to account for possible non-stationarities. The location, scale, and shape parameters of GEV are modeled step-by-step through the one-factor-at-a-time experiment. The results indicate that the GEV model of the annual maximum power loss in China exhibits a significant change of the scale parameter. By contrast, changes in location and shape parameters are not significant. Overall, the power loss during blackouts is tested to change with time, which reflects the sustained increase in the variability of power loss due to the growing size of power grids. The mean tends to be stable and the distribution type remains the same, which can be related to technological advances that improve the reliability of power grids. The non-stationary GEV model with time as a covariate can effectively analyze power loss during blackouts in China. It has the potential to be extended to describe non-stationary high-dimensional characteristics of power grids.
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