Search

Salmonella Typhi is one of the most common enteric pathogens in both humans and animals that cause by the consumption of contaminated water and foods. In silico tools are used to model a stable and reliable vaccine against such infections. In the present study, a vaccine based on the outer-membrane proteins in Salmonella Typhi, has been designed. CD4 and CD8 epitopes and B-cells were predicted. To develop the final vaccine, all epitopes were joined together by AAY, KK, and GPGPG linkers. A potent immune adjuvant known as Heparin-Binding Hemagglutinin Adhesin (HBHA) has incorporated into the N-terminal of the final vaccine. Physicochemical characteristics, antigenicity, allergenicity, and immunogenicity of construct epitopes were defined using online tools. Finally; Molecular docking of developed vaccine constructs was done with TLR4-receptor. ∆G of refined vaccine with TLR4-receptor is -3.91×10 Kcal mol with 1.93 RMSD. Probability antigenicity of CD4 and CD8 epitopes were determined. The physicochemical assay classified the protein as stable. The probability antigenic vaccine is a safe vaccine according to results that indicate that vaccine is non-allergen. In conclusion, the multi-epitope vaccine might be considered to combat typhoid fever.

The nanostructures have high potential as anodes in metal-ion batteries and they have high physical stability and efficient mechanical possessions. In this study, potential of Si76, C32, B16N16 and Al38P38 as anodes in batteries are examined. The EGap, Ead, Vcell and CTheory for Si76, C32, B16N16 and Al38P38 as electrodes in batteries are calculated and compared with graphite compounds in previous works. Results show that the Al38P38 and B16N16 as anodes in batteries have higher performance than Si76 and C32, remarkably. Finally, Al38P38 and B16N16 are proposed as effective anode materials in batteries with higher CTheory and Vcell values than graphite derivatives.

In the present study, corrosion inhibition performances of some pyrazolo [3,4-b] quinoline-3,5-dione derivatives against the corrosion of copper metal were investigated using B3LYP/6-311++g(d,p) calculation level in aqueous media. Additionally, interaction energies were calculated for all the pyrazoloquinoline derivatives compounds. In the calculations it is observed that studied molecules adsorb on metal surface with the help of electron donor heteroatoms in their molecular structures. Chemical thermodynamic parameters regarding the interaction between inhibitor molecule and copper surface were estimated and discussed. Density of the electron profile analysis and chemical electrostatic potential of nuclear charges in the molecule were applied to consider the nature of a number of probable interactions between Cu metal surface and inhibitors in terms of bond critical point (BCP). Calculated quantum chemical parameters showed that the pyrazoloquinoline derivatives including the OH and NO2 exhibit high inhibition performance.

The present study aims at investigating the impacts of the extract of Trachyspermum leaves on the mild steel corrosion in 0.1M hydrochloric acid (HCl), while highlighting its inhibitory mechanisms. The effects of mild steel corrosion in solutions of HCl were examined using the gravimetric and galvanostatic polarization techniques, along with EIS analyses. According to the EIS data, the highest coating undamaged index (83 %) after 100 h of immersion. According to the results, the maximum inhibitory effectiveness corresponding to the minimum corrosion rate could be observed at the highest desirable level of inhibitor concentration equal to 100 ppm, while the corrosion rate decreases with an increase in the extract concentration. The absorption examinations indicated the best description of the metal surface interaction by Langmuir isotherm with -31.85Kjmol-1, while obtaining the best exposure time for the Trachyspermum leaves extract adsorption into the surface of the metal in different concentrations. SEM, AFM, IR, and XRD showed the good coverage of Trachyspermum on the surface of mild steel. Based on the results of polarization, the inhibitors can play the role of a mixed inhibitor, also confirmed by the computational data.

The NHC-Boriranes are well-known compounds in main group chemistry and synthetic chemistry. In order to theoretically investigate of reactivity and thermodynamic properties of boriranes, all optimized geometries of six categories of substituted NHC(R2)-B and NHC-B(R'2) (where R or R' = NO2, CN, CHO, F, Cl, Br, H, Ph, CH3, C2H5, OCH3, OH, NH2) were performed using the density functional theory method (DFT) and 6-31G+(d) and 6-311++G(d,p) basis set. Next, the band gap, electron affinity, ionization potential, electronegativity, chemical softness–hardness, and thermodynamic parameters such as Gibbs free energy and entropy are calculated. The results have shown that substituted groups not only have a leading role in the reactivity and stability of compounds but also they are a determination of the properties of molecules. The hard molecule has a large energy gap and a soft molecule has a small energy gap and the soft substituted structures of NHC(R2)-B and NHC B(R'2) Boriranes are more reactive than hard ones.

In this study, theoretical capacity and cell voltage of carbon nanocage (C80), silicon nanocage (Si80), and germanium nanocage (Ge80) are examined as anodes of batteries through theoretical methods. The band gap energy (EGap), theoretical capacity (CTheory), cell voltage (Vcell) and open-circuit voltage (VOC) of C80, Si80, and Ge80 as anodes in Na-IB and K-IB are calculated. Here, the calculated parameters of C80, Si80, and Ge80 as anodes in Na-IB and K-IB are compared with graphite derivatives. Results show that the CTheory and Vcell of C80, Si80, and Ge80 are higher than graphite derivatives. It can be concluded the Ge80 is acceptable anodes in batteries with higher CTheory and Vcell than graphite derivatives.

A novel nanomagnetic catalyst has been synthesized by immobilization of triethanolamine lactate cellulose with Fe3O4 NPs. The prepared catalyst has been used as an efficient and recoverable catalyst for the regioselective synthesis of pyrazolo quinolones by the three-component reaction of dimedone, 5-amino pyrazolone and aromatic aldehydes in ultrasound condition. This economical catalyst provides high yields of products, short experimental time and easy workup for green synthesis of pyrazolo[3,4-b]quinolone compounds. Theoretical studies have been employed to investigate the reaction mechanism by using the B3LYP/6-311G method. Electronic parameters of all components have been determined in order to reorganize the role of components in the reaction mechanism.

An unexpected regio- and stereoselective [4 + 3] cycloaddition reaction of azomethine ylides with 5-benzylidenethiazolidine-2,4-diones has been successfully developed for the synthesis of the novel pharmacologically active 4′,5′-dihydro-3′H-spiro[indoline-3,2′-[1, 3] oxazepin]-2-one derivatives in basic condition. Easy purification, high yield, short experimental time and operational simplicity are specific advantages of this protocol. Furthermore, all the synthesized compounds have been evaluated for antioxidant and antibacterial activities. According to the results, most of the synthesized compounds exhibited DPPH radical scavenging activity and nine of them showed antibacterial properties. The reaction mechanism and 1H NMR spectrum have been evaluated by B3LYP/6311G method.

We have developed a highly sensitive sensor of ZnFe

In this study, the ability of various nanocages Si36, Ge40, Si76, B18P18, Al20N20 and Al38P38 for electrodes of Li- and Na-ion batteries (LIBs and NIBs) is investigated. Thermal stability, energy formation, ionization potential and electron affinity of Si36, Ge40, Si76, B18P18, Al20N20 and Al38P38 are calculated. The vibrational analysis confirmed that the optimized structures of Si36, Ge40, Si76, B18P18, Al20N20 and Al38P38 are true local minima on the potential energy surface. The ΔGcel1, Vcell and Ctheory of Si36, Ge40, Si76, B18P18, Al20N20 and Al38P38 for electrodes of LIBs and NIBs are examined and compared with graphite derivatives and various nanotubes. The investigated compounds are suitable candidates to propose as anodes in metal-ion batteries (MIBs). The Al38P38 is suggested as acceptable material in MIBs with acceptable efficiency.

The present study aims at investigating the impacts of the extract of Trachyspermum leaves on the mild steel corrosion in 0.1M hydrochloric acid (HCl), while highlighting its inhibitory mechanisms. The effects of mild steel corrosion in solutions of HCl were examined using the gravimetric and galvanostatic polarization techniques, along with EIS analyses. According to the results, the maximum inhibitory effectiveness corresponding to the minimum corrosion rate could be observed at the highest desirable level of inhibitor concentration equal to 100 ppm, while the corrosion rate decreases with an increase in the extract concentration. The absorption examinations indicated the best description of the metal surface interaction by Langmuir isotherm, while obtaining the best exposure time for the Trachyspermum leaves extract adsorption into the surface of the metal in different concentration. Based on the results of polarization, the inhibitors can play the role of a mixed inhibitor, also confirmed by the computational data.

Increasing use of silver nanoparticles (AgNPs) in various fields as mentioned recently like cosmetology, clinical nanotechnologies and medicine causes the growth of a nontoxic and green synthesis methodology. The present study provided a facile stable one-step synthesis of AgNPs in the presence of Artemisia herba-alba, Mentha, Rosmarinus and Ranunculus aqueous oil extract as reductant and stabilizer via oil-in-water nano-emulsion. Due to experimental results, in the presence of Artemisia herba-alba extract, AgNPs indicated smaller size, uniform shape and well dispersed NPs. Synthesized nanostructures characterized by using various techniques like XRD, UV–Vis, FT-IR, TEM, SEM, nano sizer and zeta potential measurements. The effect of some reaction parameters (the molar ratio of AgNO3, extract volume, pH and temperature) on the AgNPs investigated as well. Additionally, strong antibacterial effects of AgNPs found against four gram-negative and three gram-positive bacteria due to cell death according to increasing membrane permeability and bacterial wall integrity disruption. WST-1 exposed cytotoxicity potent index on the cancerous cell lines as established by the low IC50 value of 1 ppm. Binding energy of Ag metal with bacteria calculated by molecular docking and indicated that all bacteria have good interaction with silver NPs and confirmed antibacterial manner of Ag. Therefore, Produced AgNPs can be introduced as an effective antibacterial agent as well as a potent index of cytotoxicity effect on cancerous cell lines that leads to effective usage in nono-drug design and formulations in near future.

In crystal engineering and pharmaceutical chemistry, cocrystals have a wide range of applications. Ethenzamide (EA) is found to form cocrystal with 2-nitrobenzoic acid (NBA). Geometry properties like stability energy, charge distribution, bond length, electronic properties and thermodynamic characteristics have been analyzed. The C-H…O hydrogen bond involves C-H of EA and oxygen of NBA. Configuration with the angle, N3-C4-C5-C6 gives the lowest energy conformation. Partition coefficient value suggests that EA-NBA has pharmaceutics behavior. RMSD values show the simulation’s relative stability and the complexes, remained stable throughout.

Anthracenes are aromatic compounds with flexible structure and reactivity which are of great interest to theoretical and experimental chemists. Theoretical investigations of 1,4-dihydroxy-5,8-bis[2-(2-hydroxyethylamino)ethylamino]anthracene-9,10-dione (Mitoxantrone) (DDEA) based on density functional theory, molecular dynamics and adsorption on fullerene are reported in the present research. The suitable situation for adsorption with fullerene (C60) is the cyclohex-2-ene-1,4-dione ring of DDEA. Selected quantum-molecular descriptors have been calculated to predict the most reactive sites of the DDEA molecule. Interactions of DDEA with water have been studied using MD simulations. MD simulations were also used to study solubility parameter, a significant quantity for the development of pharmaceutical formulations. The affinity of DDEA on human dihydrofolate reductase and deoxyuridine triphosphatase enzymes was investigated by MD simulation of the protein–ligand complex obtained by molecular docking study. Communicated by Ramaswamy H. Sarma.

Novel graphitic carbon nitride-multi wall carbon nanotubes based nanocomposites decorated with different mass fraction (x = 10–50) of bio ultrasound synthesized ZnO-NPs were fabricated. The characterization of g-C3N4/MWCNT/ZnO (x) was performed in detail using a wide range of methods such as FT-IR, XRD, FE-SEM, EDS, XPS, DRS, HRTEM and N2 physisorption. Efficiency of ultrasound wave accelerated photodegradation of anxiolytic drug Alprazolam by advanced oxidation processes (AOP) was investigated in the presence of g-C3N4/MWCNT/ZnO. AOP was studied under different kind of irradiation (UVA, Vis and SSI) and photocatalyst (with different weight ratio of ZnO to g-C3N4/MWCNT), loading of photocatalyst, pH, as well as the presence of alcoholic •OH scavenger. By evaluating the effect of kinds of irradiation and photocatalysts, it was demonstrated that the UVA/g-C3N4/MWCNT/ZnO (x = 30) combination is a efficacious system for ALP removal. The dose of g-C3N4/MWCNT/ZnO (x = 30) was 1.0 mg/mL and the pH 7 was chosen as the optimal condition. The influence of •OH scavengers on the sonophotocatalysis shows that the ultrasound removal of ALP was accomplished mainly via •OH radicals.

In this study, a multiple access scheme called low density signature isotropic orthogonal transfer algorithm (LDS-IOTA) is proposed for overloading transmissions, and an analytical model for the performance limitations of this system is developed. LDS-IOTA utilises a low density signature structure for spreading the symbols in frequency domain, and applies such technique to IOTA-based filter bank multicarrier system. The input-output mutual information of LDS-IOTA is analysed for the case of finite size modulation, and LDS-IOTA is compared with OFDM as well as LDS-OFDM over multipath fadding channels.

In recent years, the discovery of efficient catalyst with low price to sulfur dioxide (SO2) oxidation in normal temperature is a major concern in the industry. In present study, in first step the boron nitride nanotube (BNNT) with Ge were adopted and the surface of Ge-adopted BNNT via O2 molecule were activated. In second step the SO2 oxidation on activated Ge-BNNT surface via Langmuir Hinshelwood (LH) and Eley Rideal (ER) mechanisms was investigated. Results show that O2 activated Ge-BNNT surface can oxide the SO2 molecule via Ge-BNNT-O-O* + SO2 → Ge-BNNT-O-O*-SO2 → Ge-BNNT-O* + SO3 and Ge-BNNT-O* + SO2 → Ge-BNNT + SO3 reactions. Results show that SO2 oxidation on activated Ge-BNNT surface via the LH mechanism has lower energy barrier than ER mechanism. Finally, calculated parameters reveal that activated Ge-BNNT is acceptable catalyst with low price and high performance for SO2 oxidation in normal temperature.

Performance of B18N18 and B18P18 as anodes in metal-ion batteries (MIBs) were examined. Effects of halogen adoption of B18N18 and B18P18 as anodes in MIBs were examined. The B18P18 as anode in MIBs has larger potential than B18N18. The K-ion battery takes larger voltage of cell and performance than Na- and Li-ion batteries. The halogen adoption of B18N18 and B18P18 improves the cell voltage of MIBs. The storage capacities of B18N18 and B18P18 nanocages for Li-ion batteries are 893 and 795 mAh/g, respectively. The cell voltages of F-doped MIBs were larger than Br- and Cl-doped MIBs. The F-B17P18 as anode in K-ion battery proposed as novel MIBs with the highest performance.

Viscosity is an essential factor to characterize phase behavior of hydrocarbons. As appropriate correlations for supercritical hydrocarbons in industrial operations are not available, in the present work, two generalized correlations are proposed to estimate the viscosity of commonly used hydrocarbons (i.e. methane, ethane, propane, i-butane, n-butane, n-pentane, n-hexane, and n-heptane). Subsequently, the cubic correlation is suggested and verified by experimental data. This correlation has a few numbers of adjusting parameters, low average absolute error (in 5.41%–6.72% range) while can cover wide ranges of pressure and temperature. Consequently, results confirm great satisfactory performance and accuracy of the developed models to estimated supercritical fluid viscosity by applying the novel strategy.

Biodiesel as an environmental friendly and renewable fuel assigns a great potential to substitution of petroleum diesel. The biodiesel characteristics are highly dependent on the structure of its basis oil. The main aim of the present work was to develop an accurate model based on LSSVM-PSO algorithm to estimate biodiesel properties, i.e., pour point, cloud point, iodine value and kinematic viscosity as a function of fatty acids composition. The temperature, molecular weight, weight percent of saturated acids, poly unsaturated fatty acids and mono unsaturated fatty acids, number of double bonds, and carbon number are involved variables for development of the models. The performance of LSSVM-PSO model is evaluated using different statistical criteria which result in the coefficients of determination of 0.99995, 0.99981, 0.99848 and 0.99930 for pour point, cloud point, iodine value and kinematic viscosity, respectively. In addition, the outcomes of the proposed model are compared with those from an ANFIS model indicating the great potential of the LSSVM-PSO model to estimate the biodiesel properties.

The discovery of acceptable catalysts to oxidation of the silicon monoxide (SiO) and nitrogen (N2) molecules has high importance. In present study, the C60 and B36N36 nanocages with Sn and Ge were adsorbed, respectively and then surfaces of Sn C60 and Ge B36N36 via O2 were activated. In this study, the oxidation of the SiO and N2 molecules on surfaces of the Sn C60 and Ge B36N36 via the Langmuir Hinshelwood (LH) and Eley Rideal (ER) mechanisms was investigated, respectively. Results showed that the Sn C60 and Ge B36N36 can oxidize the SiO and N2 molecules via C60 Sn + SiO + O2 → C60 Sn O + SiO2 and B36N36-Ge + N2 + O2 → B36N36-Ge O + N2O reactions, respectively. Results showed that the oxidation of SiO and N2 on surfaces of Sn C60 and B36N36-Ge nanocages via the LH mechanism has lower energy barrier than ER mechanism. Finally, results revealed that the Sn C60 and B36N36 Ge nanocages are acceptable catalysts to oxidation of SiO and N2 molecules with high performance.

The purpose of rotating packed bed is to intensify process conditions by using centrifugal forces. The effective interfacial area is a critical design factor and has a direct relationship with operational condition and mass transfer rate. Process intensification by the rotating packed bed is an emerging technology to improve the mass transfer rate in a high gravity system. Since there are limited modeling studies in order to control rotating packed bed parameters, in the present study, the multilayer perceptron artificial neural network (MLP) framework was successfully used to investigate the gas-liquid effective interfacial area in a rotating packed bed. In this regard, a number of 265 experimental data for the gas-liquid effective interfacial area was utilized by considering three groups including operational factors, physical dimension, and gas-liquid properties as the network’ inputs. The mean relative error and R-square as analogy factors for verification of the model accuracy obtained to be 8.2% and 0.97, respectively. Accordingly, the present model can be a huge value in the CO2-liquid system and it is introduced as a novel strategy to determine the gas-liquid effective interfacial area in a rotating packed bed.

In this study, the potential of Si14Ge14 and B14P14 as anode electrodes in metal-ion batteries by using of the density functional theory was investigated. The effects of halogen adsorption of the Si14Ge14 and B14P14 on potential of metal-ion batteries were examined. Results indicated that the B14P14 as anode in metal-ion batteries has higher potential than Si14Ge14. Results have shown that the K-ion battery has higher cell voltage and higher potential than Li-ion and Na-ion batteries. Results shown that the halogen adsorption of nanocages increases the cell voltage of studied metal-ion batteries. Results displayed that the F-metal-ion batteries have higher cell voltage and higher performance than Cl- and Br-metal-ion batteries. Finally, the F-B13P14 as anode electrode in the K-ion battery has the highest potential in industry.