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TiO2 nanoparticles are effective alternative to the antibiotics. The quick recombination of the photogenerated charges and the inefficient exploitation of visible light remain the major problems limiting their large‐scale applications. Modifying the TiO2 with Silver that acting as an electron trap, plays an important role in reducing the recombination of TiO2 charges and shift its photo‐response to the visible light region. The present work aims to synthesize AgTiO2 nanoparticles using sol‐gel and coprecipitation methods and evaluating the antimicrobial behavior of them. Also, to find the optimal conditions based on the anatase phase of TiO2 due to its higher antimicrobial activity than the rutile form. Among Ag‐TiO2 nanoparticles obtained, the one prepared by sol‐gel method at 450 °C and PH=8–8.5 exhibits the best antimicrobial property. AgTiO2 nanoparticles have been characterized by means X‐ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR),scanning electron microscope (SEM), ζ‐potential, dynamic light scattering (DLS) that showing promising results. Zeta potential values −103 mV has been reported that is considered as a stable colloidal suspension system that prevents nanoparticles aggregation. Antimicrobial behavior of them were evaluated using Diffusion (Agar disk‐diffusion), Dilution (MIC) and Bacterial colony counting methods and diameter of the inhibitory zone 15 mm and minimum inhibitory concentration 5 mg/ml was observed.Colony count results indicated that AgTiO2 able to kill bacteria at the lowest concentration of 5 mg/ml. Outcomes of MTT assay (measure cell cytoxicity) suggesting the absence of toxicity in living Hfff cells (as a normal human fibroblast) while surviving L929 cells (as a cancer cell line originated from mouse fibroblast cells). After 24 and 48 h incubation from 100 % to 77.3 % and 57.2 % was reduced respectively. This indicates that Ag/TiO2 nanoparticles act as a anticancer drug and have inherent selective toxicity nature towards cancer cells while posing no effect to normal cells. AgTiO2 nanoparticles are synthesized using sol‐gel and coprecipitation methods. The sample prepared by the sol‐gel method at a temperature of 450 °C and pH=8.5, which corresponds to the anatase phase of TiO2 synthesis, shows the best antimicrobial properties and acts as an anticancer drug with inherent selective toxicity nature towards cancer cells while posing no effect on normal cells. [ABSTRACT FROM AUTHOR]

The current investigation, interaction of Cr(CO)3 fragment with corannulene was examined at the B3LYP*/6-311G(d,p) level of theory. C-PCM study of the formed Cr(CO)3(η6- corannulene) complex was reported. Independent and dependent-frequency isotropic polariazability and first hyperpolarizability values of this complex were calculated. The solvent effect on these data were examined using conductor polarizable continuum model (C-PCM). Correlations of the energetics, electronic and optical properties with modified-Buckingham function (Fmodified-Buckingham) were illustrated. Reduced density gradient (RDG) was employed to analyze the interaction between Cr(CO)3 fragment with corannulene. [ABSTRACT FROM AUTHOR]

Electronic, structural, and optical properties of Fe(CO)4[X12Y12] (X = B or Al, Y = N or P) complexes have been illustrated at the mPW1PW91/6-311G(d,p) level of theory. Two possible isomers of the interaction between [X12Y12] nano-cluster and Fe(CO)4 have been considered. In isomer I, Fe(CO)4 fragment interacts with common X–Y bond between six-membered rings. In isomer II, this fragment interacts with common X–Y bond between six-membered and four-membered of cage. Dipole moment values, polarizability parameters, and non-linear optical properties of these complexes have been investigated. Energy decomposition analysis (EDA) has been employed to explore the interactions between nano-cluster and Fe(CO)4. Charge transfer between [X12Y12] nano-clusters and Fe(CO)4 fragment has been explored with electrophilicity-based charge transfer (ECT). QTAIM computations have been employed for illustration the characterizations of Fe–C, Fe–X, and Fe–Y bonds in the studied complexes. In addition, Laplacian bond orders (LBO) of the Fe–C, Fe–X, and Fe–Y bonds have been calculated. Independent gradient model (IGM) based on promolecular density has been used to evaluate the interaction between Fe(CO)4 and [X12Y12]. [ABSTRACT FROM AUTHOR]

The crystal structures of two single-enantiomer compounds, i.e. diphenyl [(R)-(+)-α-ethylbenzylamido]phosphate, C21H22NO3P or (C6H5O)2P(O)[NH-(R)-(+)CH(C2H5)(C6H5)] (I), and N-[(R)-(+)-α-ethylbenzyl]-P,P-diphenylphosphinic amide, C21H22NOP or (C6H5)2P(O)[NH-R-(+)CH(C2H5)(C6H5)] (II), were studied. The different environments at the phosphorus atoms, (O)2P(O)(N) and (C)2P(O)(N), allow the P O/P--N bond strengths to be compared, as well as the N--H...O P hydrogen-bond strengths, and P O/N--H vibrations. The following characteristics related to diastereotopic C6H5O/C6H5 groups in I/II were considered: geometry parameters, contributions to the crystal packing, solution 13C/¹H NMR chemical shifts, conformations, and NMR coupling constants. The phosphorus-carbon coupling constants nJPC (n = 2 and 3) in I and mJPC (m = 1, 2, 3 and 4) in II were evaluated. For a comparative study, chiral analogous structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. [ABSTRACT FROM AUTHOR]

In this work, we reported a computational investigation on the interaction between a cycloplatinated thiosemicarbazone (CT) as antiparasitic and antitumor agents with C20 molecule. The solvent impacts were considered by the SCRF based on PCM. The relationships of solvation energies, interaction energy, dipole moment, and N-H stretching frequencies (ν(NH)) values with modified-Buckingham function were illustrated. ETS-NOCV, CDA, and EDA results provided valuable understanding into the interaction between two fragments. [ABSTRACT FROM AUTHOR]

In this work, hollow Poly(aniline-co-pyrrole) (HAP) nanoparticles were synthesized and utilized accompanied by chitosan (CH) to prepare the novel HAP-CH support for metal nanoparticles. ZnFe2O4 (ZFO) nanoparticles were synthesized and incorporated on HAP-CH support to enhance the catalytic activity of Pt nanoparticles in the novel Pt-ZFO/HAP-CH nanocatalyst for methanol electro-oxidation. The prepared catalysts were characterized by Transmission electron microscopy images, Fourier-transform infrared spectroscopy, energy dispersive X-ray, and X-ray powder diffraction analysis. The electrocatalytic performance of Pt-ZFO/HAP-CH nanocatalyst was assessed towards methanol electro-oxidation by some electrochemical techniques including electrochemical impedance spectroscopy, chronoamperometry, and cyclic voltammetry, and compared with that of Pt/HAP-CH. Electrochemical results illustrated that Pt-ZFO/HAP-CH nanocatalyst has higher electrocatalytic activity and durability than that of the Pt/HAP-CH, which is owing to the higher electrochemically active surface area, higher mass activity, better durability, and lower charge transfers resistance. The superior catalytic performance of Pt-ZFO/HAP-CH nanocatalyst reveals that it can be a promising catalyst for developing direct methanol fuel cells (DMFCs). [ABSTRACT FROM AUTHOR]

The iron-based catalysts were prepared via wet-impregnation method. The composition of the final iron catalysts, regarding to the weight ratio is as follow 14%Fe/γ-Al2O3, 14%Fe/3%Cu/γ-Al2O3, 14%Fe/3%Sn/γ-Al2O3 and 14%Fe/3%Cu/1%Sn/γ-Al2O3. The catalysts were characterized using XRD, ICP, BET, H2-TPR, FE-SEM and EDX techniques. The catalytic activity was evaluated in a fixed bed reactor under 2.0 MPa of pressure, H2 : CO = 1 : 1, GHSV = 2 L h–1 , in the temperature range of 270–300°C. Then, the effect of temperature and promoters (Cu and Sn) on the catalyst performance was investigated. CO conversion and product selectivity were also calculated using the results of GC. The results showed that the Cu and Sn promoters increased the reduction rate of Fe2O3 by providing H2 dissociation sites. Higher temperatures were also shown to change the CO conversion and product selectivity. The selectivity of both methane and C2–C4 hydrocarbons decreased while the selectivity of C5+ increased because of simultaneous use of Cu and Sn for promoting iron catalyst. Sn promoter increased FT and WGS activities. [ABSTRACT FROM AUTHOR]

Cu–Fe catalysts incorporated with different amounts of Ca and Mn promoters were prepared using a wet-impregnation method and applied in the Fischer–Tropsch synthesis reaction. The composition of the final iron catalysts in terms of the weight percentage was as follows: 14Fe/3Cu/2Ca/γ-Al2O3, 14Fe/3Cu/2Mn/γ-Al2O3 and 14Fe/3Cu/1Ca/1Mn/γ-Al2O3. The catalysts were characterized by XRD, ICP, BET, FE-SEM, EDX, H2-TPR and TEM techniques. The performance of the catalysts was also evaluated in a fixed bed reactor under a pressure of 20 atm, a H2 to CO ratio of 1, a GHSV of 2 L h−1 g cat−1 and a temperature of 285 °C. Finally, the effect of Ca and Mn promoters individually and in combination with each other on catalysts' performance was investigated. CO conversion and product selectivity were calculated using the results of gas chromatography. The 14Fe/3Cu/2Mn/γ-Al2O3 catalyst exhibits a higher selectivity for C2–C4 short-chain hydrocarbons, while the 14Fe/3Cu/1Ca/1Mn/γ-Al2O3 catalyst displays a much better selectivity for C5+ long-chain hydrocarbons. The C5+ selectivity of the doubly-promoted catalyst was 61.99%, which was higher than those of Fe/Cu catalysts and singly-promoted catalysts, due to the synergistic effect of the two promoters. The doubly-promoted catalyst achieved higher CO conversion (77.6%) and yield (48.03%) than other prepared catalysts. This demonstrates that the amount of Ca and Mn promoters in the synthesized Fe-based catalysts has a great influence on the distribution of hydrocarbon products. The formation of methane and light hydrocarbons was restrained with the combination of calcium and manganese. [ABSTRACT FROM AUTHOR]

We explored solvent effect on the stability, dipole moment, polarizability and first hyperpolarizability of Fe(CO)4B12N12 complexes at MPW1PW91/6-311G(d,p) level of theory. These complexes were considered in the low spin states. The self-consistent reaction field theory (SCRF) based on conductor-like polarizable continuum model (PCM) was employed to illustration of the solvent influences. The relations between the parameters with solvent polarity functions (McRae and Suppan functions) were given. Also, relations of the wavenumbers values of the stretching of carbonyl ligands with the Kirkwood–Bauer–Magat equation (KBM) were provided. [ABSTRACT FROM AUTHOR]

For structures with a C2PO2 skeleton, a comparison of "single-and-half" phosphorus–oxygen bonds with single and double phosphorus–oxygen bonds is presented. The study is performed by considering the title structure, 63 analogous salt/zwitterionic structures with the [O–P=O]– moiety and 445 structures with a neutral O–P=O moiety retrieved from the Cambridge Structural Database. The average lengths of the single, "single-and-half " and double phosphorus-oxygen bonds were obtained as 1.58, 1.50, and 1.48 Å, which indicates the proximity of "single-and-half " bond lengths to double phosphorus–oxygen bond lengths. In the crystal structure of the title compound, the [NH2C5H4NH]+ cation, [(C6H5)2P(O)(O)]– anion and two independent water molecules are interconnected through relatively strong O–H⋅⋅⋅O and N–H⋅⋅⋅O hydrogen bonds, building a two-dimensional assembly along the ab plane. In this hydrogen-bond pattern, the oxygen atoms of the [O–P=O]– moiety act as double hydrogen-bond acceptors. [ABSTRACT FROM AUTHOR]

Nickel‐doped mesoporous carbon (MC) materials with 1, 4, and 7 wt. % nickel/MC, were synthesized and utilized for the elimination of indole, as representative of nitrogen‐containing compounds, from a model diesel fuel. Different instrumental techniques, including Fourier‐transform infrared (FT‐IR) spectroscopy, X‐Ray diffraction (XRD), N2 adsorption‐desorption analyses, field emission scanning electron microscopy (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDXS), and transmission electron microscopy (TEM) were used to characterize the synthesized Ni‐doped mesoporous carbons. The XRD and N2 adsorption‐desorption results revealed that all the nickel‐modified materials had ordered hexagonal mesostructures. Response surface methodology coupled with a three‐variable, three‐level Box‐Behnken design (BBD) involving three center points and one response was employed for evaluating the influence of the three input parameters, namely temperature (A), contact time (B), and Ni content (C) on the adsorption yield. The optimum removal efficiency (96.5 %) was obtained at 42 °C, 1 wt. % of Ni loading, and 55 min contact time; also, possible adsorption mechanisms might be due to van der Waals interaction, H‐bonding, and π‐complexation. Additionally, the equilibrium data were analyzed using Langmuir, Freundlich, and Temkin isotherm models, and the Freundlich isotherm model showed a better fit to experimental data (R2 =0.9978). [ABSTRACT FROM AUTHOR]

ABSTRACT As the world shifts towards renewable and sustainable energy sources, converting syngas into hydrocarbons using Fischer–Tropsch synthesis (FTS) catalysts is crucial. In this work, a series of copper‐modified iron‐based catalysts with cerium and strontium promoters supported on γ‐Alumina as follows were prepared using a wet‐impregnation method: FCA (18Fe/4Cu/γ‐Al2O3), FCCA (18Fe/4Cu/2Ce/γ‐Al2O3), FCSA (18Fe/4Cu/2Sr/γ‐Al2O3), and FCCSA (18Fe/4Cu/1Ce/1Sr/γ‐Al2O3). The phase, structure, and morphology of the catalysts were characterized using X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) specific surface area analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), inductively coupled plasma–atomic emission spectrometry (ICP‐AES), hydrogen temperature‐programmed reduction (H2‐TPR), and hydrogen temperature‐programmed desorption (H2‐TPD). The impacts of Ce and Sr, individually and in combination, on the structure, adsorption, reduction, and catalytic performance of the catalysts were evaluated in a fixed bed reactor at 300°C, 2.0‐MPa pressure, a time of stream of 168 h, and an H2/CO ratio of 1. The CO conversion and product selectivity were calculated using gas chromatography results, highlighting the synergistic effect of Ce and Sr promoters on hydrocarbon product distribution. The doubly promoted FCCSA catalyst exhibited a high CO conversion rate of 77.65%, CO2 selectivity of 43.5%, C2‐C4 selectivity of 55.89%, C5+ selectivity of 85.62.0%, and a yield of 43.19%, surpassing FCA, FCCA, and FCSA catalysts. Similar characteristics, CO conversion, and product selectivity were achieved for FCCSA during long‐term 336‐h FTS runs, indicating stability. [ABSTRACT FROM AUTHOR]

Magnetic oxide nanocomposite (Fe3O4@SiO2@AgO), as the photocatalytic agent, was successfully synthesized through the simple chemical method. Besides, waste rice husk was used as the green source for silicon dioxide nanoparticles. The effect of AgO on the photocatalytic performance, degradation of phenol red under visible light, of Fe3O4@SiO2 nanocomposite was examined through the absorption spectroscopy technique. The maximum degradation by Fe3O4@SiO2 nanocomposite was 55% under visible light. On other hand, after combining Fe3O4@SiO2 nanocomposite with AgO, degradation percentage was increased to 89% thanks to the effect of AgO on the charge recombination process which leads to enhancement of the electron–hole separation. In order to test the catalytic application of Fe3O4@SiO2 nanocomposite, the impact of various parameters such as contact time, SiO2 concentration, and absorbent concentration on the desulfurization process of model oil was investigated. The efficiencies of removing dibenzothiophene from the fuel by Fe3O4 nanoparticles, SiO2 nanoparticles, and Fe3O4-SiO2 nanocomposite were 34.9%, 65.6%, and 78.2%, respectively, under optimum conditions. [ABSTRACT FROM AUTHOR]

Background: Cancer continues to be one of the greatest challenges in modern medicine and is second only to cardiovascular disease as the main cause of death. Breast cancer in particular is responsible for 15% of deaths in women. In this study, Lactobacillus bulgaricus was microencapsulated using a chitosan/alginate mixture. Parameters such as chitosan, alginate, and L. bulgaricus populations were optimized using Design Expert software. The responses were loading efficiency, particle size, release, and f-potential. Subsequently, the cytotoxicity of the optimized ratio of chitosan/alginate nanoparticles was investigated on MCF-7 cancer cells. Results: The research revealed that optimal conditions for the mentioned variables were a chitosan concentration of 1% w/w, an alginate concentration of 1% w/w, and a L. bulgaricus count of 8.15 CFU/ml. Following numerical optimization, the loading efficacy = 91.15%, the release = 71.55%, the polydispersity index = 0.11, and the f-potential = 61.94 based on numerical optimization. Findings revealed that miracle drinks with L. bulgaricus-loaded chitosan/alginate microcapsule ratios exhibited toxic and potential apoptotic effects on MCF-7 cancer cells. This study showed that a miracle drink prepared with the optimal ratio of probiotic nanoparticles stops cells in the S and G2/M phases. [ABSTRACT FROM AUTHOR]

The crystal structures of two single-enantiomer compounds, i.e. diphenyl [(R)-(+)-α-ethylbenzylamido]phosphate, C21H22NO3P or (C6H5O)2P(O)[NH-(R)-(+)CH(C2H5)(C6H5)] (I), and N-[(R)-(+)-α-ethylbenzyl]-P,P-diphenylphosphinic amide, C21H22NOP or (C6H5)2P(O)[NH-R-(+)CH(C2H5)(C6H5)] (II), were studied. The different environments at the phosphorus atoms, (O)2P(O)(N) and (C)2P(O)(N), allow the P O/P--N bond strengths to be compared, as well as the N--H...O P hydrogen-bond strengths, and P O/N--H vibrations. The following characteristics related to diastereotopic C6H5O/C6H5 groups in I/II were considered: geometry parameters, contributions to the crystal packing, solution 13C/¹H NMR chemical shifts, conformations, and NMR coupling constants. The phosphorus-carbon coupling constants nJPC (n = 2 and 3) in I and mJPC (m = 1, 2, 3 and 4) in II were evaluated. For a comparative study, chiral analogous structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. [ABSTRACT FROM AUTHOR]

IN THE TITLE COMPOUND [SYSTEMATIC NAME: 2-(3,4-dihydroxy-phen-yl)ethanaminium perchlorate], C(8)H(12)NO(2) (+)·ClO(4) (-), the cations and anions are linked into three-dimensional structure via inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.