Here we obtain the new four-dimensional black hole solutions to the Einstein-power-Maxwell-dilaton gravity theory. We solve the coupled scalar, electromagnetic, and gravitational field equations in a ...static and spherically symmetric geometry and show that dilatonic potential, as the solution to the scalar field equation, can be written as a generalized Liouville potential. We obtain three classes of novel charged dilaton black hole solutions, in the presence of power law nonlinear electrodynamics, which are asymptotically nonflat and non-anti-de Sitter. Then we calculate the conserved and thermodynamic quantities from geometrical and thermodynamical approaches, separately. Since the results of these two alternative approaches are identical, one can argue that the first law of black hole thermodynamics is valid for all of the new black hole solutions. We study thermodynamic stability or phase transition of the black holes using the canonical ensemble method. The points of type-1 and type-2 phase transitions and the ranges at which the black holes remain stable are indicated by considering the heat capacity of the black hole solutions. The global stability of the black holes is studied through the grand canonical ensemble method. Regarding the Gibbs free energy of the black holes, we find the points of Hawking-Page phase transition and ranges of the horizon radii at which the black holes are globally stable.
Long-term underground cold-water cisterns had been used in old days in the hot and arid regions of Iran. These cisterns provide cold drinking water during warm seasons for local communities. In this ...paper, the thermal performance of an underground cold-water cistern during the withdrawal cycles in warm seasons is modeled. The cistern is located in the central region of Iran in the city of Yazd. Two approaches are used to model the heat transfer in the mentioned cistern. The first approach is meshless local Petrov–Galerkin (MLPG) method with unity test function and the second approach is artificial neural networks (ANN). For the ANN method, the multi layers perceptron (MLP) feed-forward neural network training by back propagation algorithm is used. Both methods are compared and a good agreement is observed between the MLPG and ANN results. The results show a stable thermal stratification in the cistern throughout the withdrawal cycle. The thermal stratification is linear in lower areas and exponential in upper areas. The exponential trend in the upper area is because of several factors such as: thermal exchange among the upper layers of water and the domed roof, transfer of mass and evaporation due to entry air from the wind towers.
In this study, we aimed at investigating the catalytic oxidative desulfurization (CODS) of the model diesel oil and real diesel oil using the vanadium-substituted Dawson-type emulsion catalyst ...(cetrimonium6+x P2W18–x V x O62 (x = 1, 3, 5)). Among all prepared samples, cetrimonium11P2W13V5O64 showed the best results in CODS of model diesel oil under determined conditions (10 g/L catalyst and O/S mole ratio = 4). The Taguchi method was then applied to optimize the catalyst dosage, hydrogen peroxide dosage, and the reaction temperature in CODS using the best emulsion catalyst. Then formic acid and acetic acid were used as a co-oxidant to improve the oxidation ability. Under optimum conditions, a mixture of H2O2/formic acid (1:1), in the presence of cetrimonium11P2W13V5O62 could remove 98% of dibenzothiophene and 82% of benzothiophene. Finally, under optimum conditions of CODS, 90% of total sulfur was removed from a real diesel sample. It is worth mentioning that we could recycle cetrimonium11P2W13V5O64, eight times without a significant decrease in catalyst activity.
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•Synthesis of novel anchored-silica vanadium-substituted Dawson-type polyoxometalate.•Selective sulfur and nitrogen compounds removal from model and real diesel oil.•The prepared ...catalyst show good ECODS and CODS efficiencies.•The reusability of catalyst was good in ECODS of model and real diesel.
The aim of this article is to study the extractive-catalytic oxidative desulfurization (ECODS) of the model oil containing several model S-containing compounds as well as N-containing compound using a heterogeneous vanadium substituted Dawson-type polyoxometalate catalyst under atmospheric pressure and temperature lower than 100 °C. The catalyst was prepared by ion exchange with alkyl ammonium derivatives covalently anchored to silica gel. The potential of this methodology was illustrated by oxidation of 100% quinoline and 80% of total sulfur in model oil containing 500 ppmw sulfur and 70% of total sulfur in model oil 1500 ppmw in less than 30 min of reaction, in the absence of solvent. However, when acetonitrile was employed as an extractive solvent, the desulfurization was increased considerably. Under the reaction conditions, activated catalyst and acetonitrile, solvent to oil ratio 1:6, could remove approximately 100% of quinoline, 95% of sulfur from 500-ppmw model oil, 87% of sulfur from 1500-ppmw model oil in less than 30 min. The catalyst is very active in ECODS and can be reused fifth times from 500-ppmw model oil and third times from 1500-ppmw model oil without an important decrease in activity. The ECODS could remove 83% of total sulfur from 1235-ppmw-S real diesel.
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•A mathematical model was developed to describe naphtha thermal cracking.•A comparison between mathematical and plant data show an acceptable agreement.•The diluting media changed to ...carbon dioxide and the model was run with CO2.•Using carbon dioxide enhances production yields and decrease coke deposition.•Using CO2 increases the run length of reactor from 80 to 100 days.
In the present study, a mathematical model for naphtha thermal cracking in the presence of steam is developed. This model can predict the behavior of cracking unit of the olefin plant. In this plant a mixture of steam and naphtha passes through cracking tubes. The major role of steam is partial removal of coke that causes different problems along the reactor such as low heat transfer and high pressure drop. In this study another diluting media such as carbon dioxide is employed instead of steam in order to investigate the effect of carbon dioxide on main products yield and operating conditions. Carbon dioxide was shown to improve not only naphtha conversion but also the yield of ethylene and other main products. It also increases the heat transfer to the coils due to the fact that in presence of carbon dioxide the coke thickness along the reactor reduces dramatically. This analysis suggests that the run length of the reactor in presence of carbon dioxide is 25% higher than that in presence of steam. It is also observed that using carbon dioxide reduces tube wall temperature, resulting in less operating and maintenance costs.
Potassium carbonate solution is a widely used solvent for CO2 removal due to its benefit in energy consumption and other economic concerns like degradation and corrosion problem. In this study, the ...solubility of CO2 in aqueous solutions of potassium carbonate was measured using pressure-decay method at temperatures of 313.15 K, 323.15 K, and 333.15 K, different pressures (up to 1.2 MPa), and different solution concentrations of 15 %wt., 20 %wt., and 30 %wt. Also, two equations of state were utilized to anticipate CO2 solubility in aqueous solution of potassium carbonate. The model is a combination of chemical equilibrium in the liquid phase and physical equilibrium between the liquid and vapor phases. For vapor-liquid equilibrium calculations, Peng-Robinson equation of state (PR-EOS) was used to present the fugacity coefficient in the vapor phase. The activity coefficient in the liquid phase was presented by Pitzer equation. Also, the values of the primitive interaction coefficients (λCO2,K+ and μCO2,CO2,K+) were optimized using the available literature data of the similar system. The results demonstrated that the performance of the thermodynamic modeling procedure was acceptable and the average absolute relative deviation (AARD) between the experimental and the predicted data was less than 2.7%.
Cholestatic disorders are divided in the extra and intra-hepatic that created due to the severe liver diseases. ABCB11 encodes the bile salt export pump and this gene is mutated in several forms of ...intrahepatic cholestasis. So far, some molecular features of this gene was studies.
Using a developed web server, we identified high number of rare codons in this gene, and four cases were related to BSEP-deficient patients which can be used for drug design.
By in-silico modelling of ABCB11, some of rare codons in different locations of ATP8b1 gene were identified and evaluated. Using several web servers a number of mutations that converted non-rare codons to rare codon in these patients were identified.
Some of these rare Codons were located at special positions by mutation of which, the new side chains do not seem suitable for protein structure and function. Furthermore, this mutation changed the protein folding rate that may have a critical role in proper folding. Thus, primary change of these codons contributes to BSEP deficiency.
This work is a comprehensive analysis of rare codons of ABCB11 and assessment of a number of these rare codon in protein levels. Rare codons evaluation can enhance our understanding of ABCB11 structural protein of ABCB11, and help us to develop mutation-specific therapies in design of new drugs.
Probiotic properties of 6 human and foodborne
Lactobacillus
strains were investigated
in vitro
with comparison to standard strains (
Lactiplantibacillus plantarum
ATCC 8014 and
Lacticaseibacillus ...rhamnosus
ATCC53103). They included viability in acidic environment (pH 2.5), survival in presence of bile salt and pepsin-pancreatin, autoaggregation, surface hydrophobicity (an indirect parameter of colonization of intestine cells), co-aggregation with pathogens (
Escherichia coli
O157:H7,
Salmonella enterica
ATCC 13076 and
Listeria monocytogenes
ATCC 7644) and antibiotic resistance. In addition, different groups of mice were fed by lactic acid bacteria for 7 days and viability of strains in mice feces were analyzed. All bacterial strains showed high survival at pH 2.5 (>98%), simulated pancreatic juice (>90%), simulated gastric condition (>77%) and also high resistance against bile salt (>89%).
L. rhamnosus
M1, isolated from cow milk, showed the greatest average surface hydrophobicity (63.7%), auto-aggregation (80.6%) and co-aggregation. Different strains of
L. plantarum
had resistance to the tested antibiotics, except for M8, which was sensitive to kanamycin and chloramphenicol. Among
L
.
rhamnosus
strains, M1 and RHM were the most sensitive to antibiotics demonstrating susceptibility to erythromycin. Oral feeding of the isolated strains caused beneficial effect reducing microbial amount on Plate Count and MacConkey agars in mice feces during 7 days.
L. rhamnosus
M1 and
L. plantarum
M8 are considered to be the best suitable candidates for probiotic strains because they showed a wide range of antimicrobial properties, resistance to acid and bile and survival in gastric and intestinal colonization.
The normal is a popular random effect distribution perceived to identify the correlation between the baseline or initial response and subsequent responses in the analysis of longitudinal data. In ...this article, we apply more flexible skew-normal random effects in modeling initial responses for the ordinal longitudinal data which include normal as a member. Furthermore, the correlation structure between the baseline response and the consequent responses is studied. Our results indicate that the skew-normal random effects produce the best results in modeling initial conditions for longitudinal ordinal data. Various types of simulation studies are applied to investigate the properties of the proposed model in different scenarios. We found that the baseline observation includes the pre-sample information of the process affecting the structure of random effects and explanatory variables of the proposed model. The developed model is illustrated as an application to the Schizophrenia Collaborative Study data.
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