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The work herein describes the electrochemical detection of heavy metal ions, specifically cadmium and lead. The introduction and modification of functional groups such as Schiff bases leads to an enhanced sensitivity of the electrode to analytes. In this study, a platinum electrode has, for the first time, been modified with poly(3,4-ethylenedioxythiophene) (PEDOT/Schiff base) in CH2Cl2 containing Bu4NPF6 to detect cadmium(II) and lead(II) ions. The structures and morphologies of the polymer coatings were characterised via Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The electrochemical synthesis and redox state response in monomer-free synthesised films have been studied via cyclic voltammetry. Moreover, the effect of scan rate on the electrochemical behaviour of the modified electrodes was also studied. The voltammetric findings have been used to calculate the surface coverage required for the polymer films and the stability of polymer electrodes in the monomer-free solutions. Square wave voltammetry was applied for the determination of cadmium(II) and lead(II) ion concentrations and to assess the effects of pH on aqueous samples. The limits of detection for the modified electrode for cadmium(II) and lead(II) were found to be 0.95 μg L−1 and 1.84 μg L−1, respectively. These findings revealed that modified films can be considered good candidates for application in electrochemical detection devices.

The emission and fate of methyl mercaptan from the residential complex treatment plant (RCTP) moving bed bioreactor (MBBR) process in the city of Al-Hur in Karbala governorate in Iraq were studied using the TOXCHEM 4.1 model. The release of odorous sulfur compounds from treatment plants harms workers and the surrounding area. Methyl mercaptan, in particular, is responsible for odors similar to rotten cabbage. The sensitivity analysis for the methyl compounds in the MBBR system was conducted based on the following factors: a large thick biofilm layer, the specific surface area of media, media fill fraction, and aeration flowrate. The model was validated via RMSE and R, which showed the model outputs are representatives of real-world observations. Degradation and emission were shown to be the two most important processes in the system. During the summer (32 °C) and winter (12 °C), about 13 and 10%, 2 and 4%, 0.5 and 1%, and 85 and 85% were emitted into the atmosphere, discharged with effluent, sorbed into sludge, and biodegraded, respectively. The overall concentrations of CH4S emitted in summer and winter were 1.78 and 1.38 ppm, respectively. Operating the MBBR system with a thick biofilm layer, a large specific surface area of media, a greater media fill fraction, and a low aeration rate contributed significantly to the decomposition of methyl mercaptan and thus decreased emission into the atmosphere. Finally, the TOXCHEM simulation accurately predicts the fate of CH4S and the emissions inherent to the MBBR system. The manipulation of the operating factors led to the improvement of the system and the reduction of methyl mercaptan gas emissions without the need to add units and chemical additives.

In this study, a new type of multifunctional material PANI/NiO/MnO2 nanocomposite was first time prepared by chemical polymerisation from aniline monomer in the presence of metal oxides (NiO and MnO2) and an oxidant (ammonium persulfate) in acidic aqueous solution for the elimination of methyl orange (MO) dye from water. Herein, the PANI/NiO/MnO2 nanocomposite was found to be a favourable adsorbent for wastewater treatment due to its high adsorption and efficiency, self-regeneration, low cost and easy synthesis. Fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric analysis, transmission electron microscopy, scanning electron microscopy, Brunauer–Emmett–Teller analysis and Zeta potential were employed to characterise the synthesised nanocomposites. The data revealed that PANI nanocomposites doped with NiO and MnO2 nanoparticles had a higher adsorption efficiency (~ 97%) than that found in pure PANI (~ 53%). The adsorption conditions, such as pH of the medium, initial dye concentration, adsorbent dosage, and adsorption time were investigated. Various kinetic and isotherm models were used to analyse the results of the kinetics and the equilibrium adsorption and to interpret the interaction between the dye and nanocomposite adsorbents. The adsorption kinetics data for MO dye on the PANI/NiO/MnO2 were well explained based on a pseudo-second-order model while adsorption isotherm results were analysed based upon the Langmuir isotherm model. In addition, the adsorption process was an endothermic, favourable and spontaneous reaction according to thermodynamic studies. Also, the influence of matrix synthetic waste on MO dye removal was studied and found to show good results with matrix synthetic waste for both PANI/NiO/MnO2 and PANI adsorbents. The experimental adsorption capacity of the PANI/NiO/MnO2 nanocomposite (248.4 mg/g) was considerably greater than that of PANI (57.5 mg/g). The PANI/NiO/MnO2 adsorbent can be recycled up to four times and maintains a good adsorption capacity throughout.

In this study, the catalyst activity of Fe2O3 supported on Graphene for Iraqi gas oil oxidation desulfurization (ODS) by hydrogen peroxide (H2O2) was investigated. The prepared catalyst was synthesized by wet impregnation for ferric nitrate as a Fe2O3 precursor while Graphene represented as catalyst support. The synthesized catalyst was characterized by XRD, FTIR, and EDS analysis. The experiments were designed according to three-level for three variables by Box-Behnken experimental design; Stirring time, catalyst dosage and temperature while the sulfur removal efficiency acts as experiment response. Catalyst activity was studied by ODS reaction for Iraqi gas oil (sulfur content 9400 ppm) at temperature range (40-60 ºC), stirring time (160-240 minutes) and catalyst dosage (0.5-2.5 g), the results show maximum sulfur removal efficiency 90% at stirring time, catalyst dosage and temperature 240 min, 1.5 g, and 60 ºC, respectively. ANOVA analysis shows the important effect of each independent variable on sulfur removal efficiency (response) as following influential order; stirring time, reaction temperature and catalyst dosage. Kinetics calculation showed that the ODS reaction obeys pseudo first-order reaction with reaction rate constant equal 1.0837, 1.5893, and 2.5053 at temperature 40, 50, and 60 ºC, respectively, while activation energy equal 36.26 kJ/mol. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

The electrodeposition of cobalt from alternative electrolytes, including ionic liquids and deep eutectic solvents (DES), has become a topic of great interest to the scientific community, with a significant impact in both academic circles and in the development of commercial industrial electrochemical processes. However, very few studies have considered the effects of water on the electrodeposition of metals from deep eutectic solvents. In this work, the electrodeposition of Co from a choline chloride (ChCl) ethylene glycol (EG)-based deep eutectic solvent (DES) containing 10%, 20% and 30% water has been studied, and for the first time a uniform and bright Co deposit has been obtained when the deposition was achieved from an electrolyte containing 20% water. The speciation of Co in a mixed 1:2 ChCl:EG-based liquid (Ethaline 200) has been studied in both the absence and presence of water. The conductivities of the Co electrolyte were increased with increasing amounts of water. The electrochemical properties of the Co electrolytes have been studied using cyclic voltammetry, where it was found that the redox peak current gets larger and shifts in a positive direction when water was included in the Co solution. The resultant surface morphologies, topography, and roughness of the Co deposits were revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), which demonstrated that a highly uniform and smooth cobalt coating had been produced when the deposition occurred in Ethaline 200 containing 20% water.

The use of additives to modulate metal electrodeposition from deep eutectic solvents has, to date, apparently been of little interest given the dearth of such studies in the literature. Here, we have actively investigated the effects of nicotinic acid (NA) on the electrodeposition of copper in a choline chloride (ChCl)-ethylene glycol (EG)-based deep eutectic solvent (DES), (1ChCl:2EG), considered a “green solvent” due to its physiochemical properties. Bright copper deposits were formed when NA was added to the Cu electrolyte, while a dull Cu deposit was produced in its absence. New Cu species were found to have formed in the 1ChCl:2EG-based liquid when NA was added to the electrolyte. A number of analytical techniques, in this instance cyclic voltammetry, chronoamperometry, and chronocoulometery, have been employed to determine the various electrochemical properties, nucleation mechanisms, and kinetics of the Cu species reported herein. The diffusion coefficient for the Ethaline-Cu system was found to be affected by the concentration of NA. An electrochemical quartz crystal microbalance (EQCM) was used to monitor the current efficiency of the copper deposition in both systems. The morphologies, thicknesses, roughnesses, and crystal structures of the copper electrodeposited from the NA-modified electrolyte were characterised via scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD), which between them demonstrate that the NA introduced into this system acts as a highly effective brightener, producing highly uniform and smooth copper deposits.

We report herein the electrochemical polymerisation of aniline from a choline chloride (ChCl)-based deep eutectic solvent (DES) at room temperature in both the presence and absence of deionised water in the solvent. The current study used Propeline as the DES electrolyte, which we found to be rich in protons (i.e. similar to protic ionic liquids) and which allowed the polymerisation of aniline in this system. The morphology of films was characterised by scanning electron microscopy (SEM) and atomic force microscopy (AFM), which showed the polymer film to have a compact structure and rough surface. The electrochemical quartz crystal microbalance (EQCM) was used for the first time to investigate the mass changes that occur during the electrochemical deposition of polyaniline (PANI) in situ, and was used to monitor cation, anion, and solvent transport when PANI films were immersed in pure Propeline and 0.5 M H2SO4 solution (monomer free) at 25 °C and 50 °C. In the case of the PANI exposed to pure Propeline at room temperature, the mass change increased continuously in both oxidation and reduction switching due to anion transfer dominating the mass change, while the PANI exposed to pure Propeline at 50 °C was found to form due to a two-step combined mechanism, showing excellent redox switching stability with changing mass. These variations in mass tend to be dominated by cation expulsion in the first oxidative process (the later reductive process being cation insertion) and by anion insertion in the second oxidative stage (the early reductive process being anion expulsion). In aqueous systems, the mechanism of mass change was dominated by anion movement associated with solvent transfer. The movement of neutral species in Propeline and water is in the reverse direction to those of cation or anion transfer.

The effects of nicotinic acid (NA), boric acid (BA) and benzoquinone (BQ) on the electrodeposition of Zn have been studied in a choline chloride (ChCl) ethylene glycol (EG) based deep eutectic solvent (DES), (1ChCl:2 EG), and for the first time a bright zinc coating has been achieved when NA was used. In metal electroplating processes, small-molecule additives are often included in the plating bath to improve properties of coating such as brightness, roughness, thickness, hardness and resistance to corrosion. The effects of additives on the electrodeposition of Zn from aqueous solution have been extensively investigated. However, very few studies have considered the effects of additives on the electrodeposition of Zn from ionic liquids or deep eutectic solvents. The electrochemical properties of the plating liquid have been studied here using cyclic voltammetry, chronocoulometry, chronoamperometry and microgravimetry (EQCM). Redox peak currents decrease when additives were included in the Zn solution and total charge was also reduced in experiments where additives were present. The Zn deposition in the absence of additive is in good agreement with an instantaneous growth mechanism at short experimental time scales (being indeterminate over longer periods), however, this changes to one of a progressive growth mechanism when additives were included in the coating bath. The current efficiency of zinc deposition in the DES without additives was 95%, which was reduced when additives were included. The resultant surface morphologies, thickness, topography, roughness and crystal structure of the Zn coating were revealed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD), demonstrating that those additives serve as effective brighteners that can produce highly uniform and smooth zinc deposits.

The work herein concentrates on the electrochemical detection of heavy metal ions, specifically cadmium and lead ions. The introduction and modification of functional groups such as Schiff bases had led to an enhanced sensitivity of the electrode to analytes. In this study, a platinum electrode has for the first time been modified with poly(3,4- ethylenedioxythiophene) (PEDOT/Schiff base) in CH2Cl2 containing Bu4NPF6 for use to detection cadmium (II) and lead (II) ions. The structure and morphology of the polymer coatings were characterised by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), respectively. The electrochemical synthesis and redox state response in monomer-free synthesised films have been studied by cyclic voltammetry. Moreover, the effect of scan rate on the electrochemical behaviour of the modified electrodes was also studied. The voltammetric findings have been used to calculate the surface coverage required for the polymer films and the stability of polymer electrodes in the monomer-free solutions. Square wave voltammetry (SWV) was applied for the determination of cadmium (II) and lead (II) ion concentrations and to assess the effects of pH on aqueous samples. The limits of detection for the modified electrode for cadmium (II) and lead (II) were found to be 0.95 μg L-1 and 1.84 μg L-1, respectively. These findings revealed that modified films can be considered good candidates for application in electrochemical detection devices

Pseudomonas aeruginosa is one of the most life-threatening pathogen. It is considered nosocomialopportunistic microbe that cause wide range of infections including wound and burn infections, respiratoryinfections, and Otitis media. Despite the efficiency of antibiotics against infectious diseases, P. aeruginosastill causes complicated infections with antibiotic resistance in many clinical strains. The pigments producedby P. aeruginosa exhibits antibacterial properties. Thus, we have examined its ability to enhance antibioticseffect against some pathogenic microbes. 286 samples were collected from patients with different infectionswho visited Mosul hospitals. 76 samples were positive to P.aeruginosa. Among them, 38 (13.28%) of isolateswere isolated from surgical infection, whereas, 12 (4.19%), 11(3.84%), and 7(2.447%) were isolated fromOtitis media, Urinary tract infection, and pus, respectively. The pyocyanin in low concentrations showedsynergistic effect with some antibiotics against Staphylococcus aureus and Escherichia coli. E. coli becamesensitive to ciprofloxacin and nalidixic acid when mixed with 100 mg/ml pyocyanin. However, cloxacillindid not show any activity against Staph.aureus when mixed with 1 mg/ml and 6.25 mg/ml pyocyanin. Staphaureus became sensitive to nalidixic acid when mixed with 1 mg/ml pyocyanin.

Electroactive polymers such as polyaniline and its derivatives have many potential applications, but the nature of the dopants can have an adverse effect on their properties. Polyaniline (PANI), poly(o-methoxyaniline) (POMA) and poly(o-toluidine) (POT) have been synthesised using appropriate organic acid dopants (2-naphthalenesulfonic acid and 1,5-naphthalenedisulfonic acid) via electrochemical and chemical polymerisation methods, where the later was achieved at pH (1–2) in the presence of ammonium persulfate as an oxidant. The effects of the monomers and organic dopants on the physiochemical properties and morphological surface of the polymers were studied by means of Fourier transform infrared spectroscopy, electrical conductivity measurements, thermogravimetric analysis and scanning electron microscopy (SEM). The above films were also synthesised electrochemically whilst varying conditions such as scan rate, scan number and in aqueous solution of organic acids using cyclic voltammetry techniques. Cyclic voltammetry experiments have been employed to analyse the growth behaviour and electrochemical stability of films in the background electrolytes (monomer-free). It was found that PANI salts displayed higher doping levels and conductivity while POMA and POT salts were found to show lower conductivity and doping levels, respectively. Furthermore the electrochemical response of films was different in the stability and this may be because of the methoxy (–OCH3) and methyl (–CH3) groups located at the ortho position of the aromatic ring structure of the monomers (o-methoxyaniline and o-toluidine). The –OCH3 and–CH3 groups have significant steric effects and can reduce to form long chains of polymers and also decrease conductivity. The SEM showed that the morphologies of the prepared conducting polymers were different, which was associated with the nature and size of the dopant and monomer present in the bath solution.

In this work we report the created films of poly derivatives of aniline by using electropolymerization on platinum (Pt) electrode surface in non-aqueous electrolyte (Ethaline). The electropolymerization process of poly (3-amino benzoic acid) was happened in two electrolytes H2SO4 and HClO4 using a chronoamperometry (constant potential) technique for different times (50s, 100s, and 200s). All synthesized conducting polymer films were characterized by using FT-IR. Scanning electron microscopy (SEM) has been applied to study the morphologies of polymer samples. The electrochemical behaviour of prepared conducting films have studied by cyclic voltammetry. The overall findings shown that use a different electrolyte has led to the produce of various polymeric surface films as shown by scanning electron microscopy (SEM). Moreover, the charge consumed during the electropolymerization was calculated with time.

This work will show, for the first time, the effect of nicotinic acid (NA) and 2-methylnicotinic acid (MNA)on the synthesis and properties of conducting polyaniline (PANI). The work investigates the effects of sulphuric acid (H2SO4), nicotinic acid (NA), and 2-methylnicotinic acid (MNA) on the synthesis and properties of polyaniline. The results show that the preparation of polyaniline from a sulphuric acid electrolyte is faster than the preparation from nicotinic acid and 2- methylnicotinic acid electrolytes. Moreover, the electrical conductivity and thermal stability of PANI/H2SO4 were greater than PANI/NA and PANI/MNA. All the polymers prepared in this study were identified using FT-IR. Scanning electron microscopy (SEM) was used to examine the morphologies of the PANI samples, from which it was determined that PANI/H2SO4 has a fibrous and open structure with a higher porosity morphology compared to PANI/NA and PANI/MNA. The electrical conductivities of the PANI samples were measured as 1.09 S cm-1, 0.65 S cm-1 and 0.089 S cm-1 for PANI/H2SO4, PANI/NA and PANI/MNA, respectively. The thermal stability of PANI was examined using the Thermogravimetric Analysis (TGA) technique. PANI/H2SO4 was found to degrade between 450-500°C, while PANI/NA and PANI/MNA decomposed at temperatures between 300-400°C.

This research was aimed to study the efficiency of activated carbon to remove Disinfection By-Products (DBPs) from drinking water. This work studies the main compounds of DBPs Trichloromethane (TCM) and Trichloroacetic acid (TCA) at the effect of Temperature (25−35 C°), pH (4−9), adsorbate initial concentration (4−124 mg/l) for TCM, (4−100 mg/l) for TCA and adsorbent weight (15−20 g) of activated carbon. The results show that the adsorption capacity decreases with temperature and pH increasing, and increases with initial adsorbate concentration and adsorbent weight increasing. The kinetics of the adsorption was studies and the results showed that it followed the pseudo-first-order kinetics, also the thermodynamic parameters were determined for adsorption process where the results showed that the adsorption of TCM and TCA on activated carbon was spontaneously and exothermic. The Langmuir and Freundlich isotherms constants were determined for TCM and TCA, at the end of this work eight tap water samples from Baghdad University tap water were tested to determine TCM and TCA concentrations then treated with activated carbon where the removal efficiency was (98.1% − 99.37 %).

Catabolism of galactose by Streptococcus pneumoniae alters the microbe’s metabolism from homolactic to mixed acid fermentation, and this shift is linked to the microbe’s virulence. However, the genetic basis of this switch is unknown. Pyruvate formate lyase (PFL) is a crucial enzyme for mixed acid fermentation. Functional PFL requires the activities of two enzymes: pyruvate formate lyase activating enzyme (coded by pflA) and pyruvate formate lyase (coded by pflB). To understand the genetic basis of mixed acid fermentation, transcriptional regulation of pflA and pflB was studied. By microarray analysis of ΔpflB, differential regulation of several transcriptional regulators were identified, and CcpA, and GlnR’s role in active PFL synthesis was studied in detail as these regulators directly interact with the putative promoters of both pflA and pflB, their mutation attenuated pneumococcal growth, and their expression was induced on host-derived sugars, indicating that these regulators have a role in sugar metabolism, and multiple regulators are involved in active PFL synthesis. We also found that the influence of each regulator on pflA and pflB expression was distinct in terms of activation and repression, and environmental condition. These results show that active PFL synthesis is finely tuned, and feed-back inhibition and activation are involved.

Novel polyaniline (Pani) and/or graphite (Gr)/molybdenum dioxide (MoO2) composites have been successfully synthesised via an in situ chemical polymerisation method using a Deep Eutectic Solvent (DES) as the electrolyte. The chemical structure and properties of the Pani composites were characterised using various analytical techniques such as Raman, FTIR and UV–Vis spectroscopies, Thermo-Gravimetric Analysis (TGA), X-ray diffraction (XRD) and conductivity measurements, confirming its semi-crystalline nature. The results show shifts in the Raman, XRD and FTIR spectral features associated with the Pani composites, indicating that a matrix of metal oxide and/or graphite had formed in the polymer. Higher electrical conductivity was observed for the Pani/Gr (5.58 S cm−1) and Pani/Gr/MoO2 (9.87 S cm−1) composites compared to pure Pani (1.25 S cm−1). The homogenous growth of Pani chains on the graphite and MoO2 network were clearly observed by Scanning Electron Microscopy (SEM) and Energy Dispersive Analysis by X-ray (EDAX). A larger surface area and greater porosity were achieved in the Pani/MoO2, Pani/Gr/MoO2 and Pani/Gr samples, while a more compact structure was obtained for the Pani sample. These findings support that the idea that the polymer/graphite composites would be more useful for electrochemical charge transport, supercapacitance and energy storage applications compared to those using the pure polymer alone.

This article describes the electroplating of Zn Ni alloy from a modified deep eutectic solvent (DES), a mixture of choline chloride (ChCl) and ethylene glycol (EG) commonly known by its commercial name Ethaline. In this study the Ethaline was modified with propylene carbonate (PC) to decrease the solution viscosity. Boric acid was also used as an additive to improve surface finish and adhesion. The modifications were shown to increase the reduction rate of metal ions through improved mass transport and also to improve the quality of finish (morphology and interfacial adhesion) of the coating. We demonstrate that it is possible to produce dense, thick and adherent coatings of a γ-phase Zn Ni alloy with 81–85% Zn on mild steel substrates using either potentiostatic deposition or controlled current pulse-plating techniques. Mild steel is a typical substrate for a sacrificial anti-corrosion coating used in many applications where the alloy serves to protect the steel from corrosion in harsh environments.

For the generation of energy, the important human pathogen Streptococcus pneumoniae relies on host-derived sugars, including β-glucoside analogs. The catabolism of these nutrients involves the action of 6-phospho-β-glucosidase to convert them into usable monosaccharaides. In this study, we characterized a 6-phospho-β-glucosidase (BglA3) encoded by SPD_0247. We found that this enzyme has a cell membrane localization and is active only against a phosphorylated substrate. A mutated pneumococcal ΔSPD0247 strain had reduced 6-phospho-glucosidase activity and was attenuated in growth on cellobiose and hyaluronic acid compared to the growth of wild-type D39. ΔSPD0247-infected mice survived significantly longer than the wild-type-infected cohort, and the colony counts of the mutant were lower than those of the wild type in the lungs. The expression of SPD_0247 in S. pneumoniae harvested from infected tissues was significantly increased relative to its expression in vitro on glucose. Additionally, ΔSPD0247 is severely impaired in its attachment to an abiotic surface. These results indicate the importance of β-glucoside metabolism in pneumococcal survival and virulence.

The generation and accumulation of environmental pollutant of industrial contaminations gave it a big challenge to develop many removal strategies of pollution. Textile dyes as dispersive blue 26 dye affected by several decolorization parameters like as temperature, initial pH and initial concentrations of dye. These variables parameter were studied on ZnO-dye suspension solution in dark and photoreaction conditions. In dark reaction, with using thermodynamic and kinetic parameters such as ΔH°, ΔS°, ΔG° and Ea, the type of adsorption was determined and found as a physical adsorption, exothermic and fast reaction. Moreover, the results demonstrated that the photoreaction process under UV-light-A would elevated the rate of reaction, percentage of decolorization and accelerated the half-time of decolorization reaction in 50 ppm of dye. The photoreaction of decolorization of this dye acts as pseudo first order kinetics with endothermic, less random less, non spontenous and fast reaction.

The effects of additives on the electrodeposition of Zn Sn alloy from aqueous electrolyte have been the subject of considerable interest in the literature; however, to date there has been little consideration of their effects on alloy electrodeposition from Deep Eutectic Solvents (DESs). This work will show, for the first time, the effects of boric acid, ammonium chloride and nicotinic acid on the electrodeposition of Zn Sn alloys on copper from a DES consisting of a stoichiometric 1:2 mix of choline chloride and ethylene glycol (Ethaline 200). Cyclic voltammetry has been used to study the electrochemical properties of the Zn Sn electrolyte, and the resultant surface morphologies, composition and roughness of the Zn Sn coating were revealed via SEM/EDX and AFM, demonstrating that boric acid and nicotinic acid function as very effective brighteners, producing highly uniform and smooth Zn Sn deposits. It was found that these additives strongly affect the morphology, composition, and roughness of the Zn Sn coating. XRD was also used to examine the crystal structure of Zn Sn coatings, where it was found that the phase composition of the deposits depends on the additive(s) used. In addition, corrosion of the Zn Sn alloy in salty media was measured using the Tafel method.

In this study, the effects of ion-beam parameters on the mechanical, optical and inner structural characteristics of niobium pentoxide (Nb2O5) thin films is investigated. Where a vacuum coating system equipped with a gun of an electron beam at ambient substrate temperature is employed to precipitate Nb2O5 films onto substrates of dissolved silica glass via electron-beam supported by oxygen ions. It is found that the extinction coefficient, the crystalline phase, refractive index, and residual stress are heavily affected by current density and the energy of ion. The transformations in crystallinity, from amorphous to hexagonal transition, revealed in minimum residual stress of –455 *107 psi. The optical band gap and refractive index increased up to 0.96 and 2.32 respectively, as well as a very low extinction coefficient of 10−3 for precipitation at an ion energy of 0.8 KeV and 0.025 mA/cm2 current density.

The present work provides to treat real oily saline wastewater released from drilling oil sites by the use of electrocoagulation technique. Aluminum tubes were utilized as electrodes in a concentric manner to minimize the concentrations of 113400 mg TDS/L, 65623 mg TSS/L, and the ions of 477 mg HCO3/L, 102000 mg Cl/L and 5600 mg Ca/L presented in real oily wastewater under the effect of the operational parameters (the applied current and reaction time) by making use of the central composite rotatable design. The final concentrations of TDS, TSS, HCO3, Cl, and Ca that obtained were 93555 ppm (17.50%), 11011 ppm (83.22%), 189ppm (60.38%), 80000ppm (22%), and 4200 ppm (25%), respectively, under the optimum values of the operational parameters (1.625 Amps and 40 min). In spite of the low removal percentages of some pollutants, the present study proved the ability of this novel designed reactor for treating high saline real oily wastewater in accordance with the operational parameters. This prove the capability of the use of it as a pre-treatment of other conventional methods., Chemical engineering; Environmental chemical engineering; Chemical reaction engineering; Electrochemical engineering; Adsorption; Water treatment; Real oily saline wastewater; TDS; TSS; HCO3; CL; Ca; Electrocoagulation reactor; Optimization.

Pneumococcal neuraminidase is a key enzyme for sequential deglycosylation of host glycans, and plays an important role in host survival, colonization, and pathogenesis of infections caused by Streptococcus pneumoniae. One of the factors that can affect the activity of neuraminidase is the amount and position of acetylation present in its substrate sialic acid. We hypothesised that pneumococcal esterases potentiate neuraminidase activity by removing acetylation from sialic acid, and that will have a major effect on pneumococcal survival on mucin, colonization, and virulence. These hypotheses were tested using isogenic mutants and recombinant esterases in microbiological, biochemical and in vivo assays. We found that pneumococcal esterase activity is encoded by at least four genes, SPD_0534 (EstA) was found to be responsible for the main esterase activity, and the pneumococcal esterases are specific for short acyl chains. Assay of esterase activity by using natural substrates showed that both the Axe and EstA esterases could use acetylated xylan and Bovine Sub-maxillary Mucin (BSM), a highly acetylated substrate, but only EstA was active against tributyrin (triglyceride). Incubation of BSM with either Axe or EstA led to the acetate release in a time and concentration dependent manner, and pre-treatment of BSM with either enzyme increased sialic acid release on subsequent exposure to neuraminidase A. qRT-PCR results showed that the expression level of estA and axe increased when exposed to BSM and in respiratory tissues. Mutation of estA alone or in combination with nanA (codes for neuraminidase A), or the replacement of its putative serine active site to alanine, reduced the pneumococcal ability to utilise BSM as a sole carbon source, sialic acid release, colonization, and virulence in a mouse model of pneumococcal pneumonia., Author summary Neuraminidase activity is critical for pneumococcal colonization and virulence as it is required for efficient cleavage of host glycans for nutritional requirements, attachment, and translocation of the microbe through biological membranes. Modifications, such as O-acetylation, in terminal sialic acid can affect the potency of neuraminidase. In this study we investigated whether pneumococcal esterases could potentiate neuraminidase activity by de-acetylating sialic acid. We found that the pneumococcal esterase activity is coded by at least four genes, specific for short acyl chain esters, and the removal of acetylation by esterases potentiates pneumococcal neuraminidase activity for mucin utilisation, colonization and virulence. Hence, this study elucidates the complexity and importance of host de-glycosylation for pneumococcal colonization and virulence, and reveals a potential target for therapeutic intervention.

An economic and sensitive method was developed to measure pyridoxine hydrochloride (vitamin B6) in pharmaceutical formation as an ion pair, as depending on the charge transfer reaction with SDS as a surfactant and a suitable analytical reagent (chlorazol black). The parameters that gave optimum reaction conditions, such as the concentrations of chlorozal black, SDS, pH, equilibration temperature, time and effect of salting were studied to obtain a linear calibration curve where the linearity range was found to lie between 1.22 × 10-3to 34 × 10-2mM, and the detection limit (LOD) 2.56 × 10-4mM. The method was applied successfully to determine vitamin B6 concentrations in various pharmaceutical samples.

A modern and easy procedure performed using the turbidity method for the pre-concentration and estimating of Cu (II) in pharmaceutical samples. The limited solubility complex formed by the reaction of copper ions with cysteine and SDS as the surfactant. The copper content measured using the turbidity method. The effect of chemical and physical parameters including grouping of the ligand, SDS, pH, equilibration temperature and time and effect of salting are studied. The analytical qualities of the technique have been determined, which includes linear range (the range was between 0.158 -47.625µgmL 1), the coefficient of turbidity (k=13.21), limit of detection (LOD=0.1767 µg ml 1nd LOQ=0.5355 µg mL 1).All values are calculated using statistical programs, but the detection limit for Cu(II) ions based on eight times the standard deviation of the blanks (N:8) characterized as 3Sb/m (where Sb is the standard deviation of the blank and m is the slope of the calibration curve) is 0.0096µg mL-1 (3s). The method employed successfully for the determination of Cu2+ in different local pharmaceutical formations.

The present study was designed to evaluate changes in peripheral markers of oxidative stress, oxidative DNA damage and some biochemical markers during chronic HgCl 2 intoxication and to examine how the workers respond chronically to this pollutant. Fifty (50) fasting male workers, age range 28-61 years exposed to mercury in a chloroalkali factory at Al-Furat company in Babylon governorate, range duration period 5-18 years and 30 controls matched for age, diet and other demographic characteristics except exposure to chemicals were selected. Lipid peroxidation marker Malondialdehyde (MDA), antioxidant status markers enzymatic Superoxide Dismutase (SOD), Glutathione Peroxidase (GPx), non enzymatic antioxidant markers, Glutathione (GSH), vitamin C, vitamin E and oxidative DNA damage by comet assay were determined. Blood Mercury levels were significantly higher in the workers G2 and G3 groups compared with controls group G1 (p

Poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) flat sheet membranes were prepared for aqueous membrane distillation (MD) applications using triethyl phosphate (TEP) as less-toxic solvent via phase inversion. PVDF-HFP concentrations of 10, 12 and 15 wt.% were investigated and it was observed that different polymer concentrations led to membranes with different surface structure and performance; the use of different coagulation bath compositions played a key role in the membrane fabrication and affected the performance in membrane distillation. The results showed that the permeation decreased sharply when the polymer concentration increased from 12 to 15 wt.%. By adding isopropanol as non-solvent to coagulation medium led to interesting results in terms of permeation. However, the use of lithium chloride to the casting solution had also a positive impact on membrane characteristics in price of retrograde membrane mechanical properties. Particularly interesting was the membrane produced from solution containing the 12 wt.% polymer and coagulated in the isopropanol–water mixture, which gave a DCMD permeation of 16.1 kg h −1 m −2 at feed temperature of 60 °C, and a salt rejection of 99.3%.

Phases’ evolution during the solidification of a hypoeutectic 3.92% C-equivalence cast iron was modelled by considering the cooling history of the alloy from the melt, thus including both solidification and solid state transformations. Simple Fourier model was used to combine macroscopic heat flow and microscopic kinetics for phase evolution. Different cooling rates were obtained by casting cylinders and stepped plates. Measured number of primary austenitic nuclei, eutectic cells and volume fraction of phases during solidification (graphite, a-ferrite, pearlite and cementite), are correlated with the cooling rate. Growth rate constants for primary austenite, are found to be  = 8.7E-7, and n = 2.3. Growth rate constants for primary graphite (types A, B, and C), are found to be  =5.7E-7, and n = 2. The model matches with the experimental work where the error percent of modelling volume fractions of pearlite, graphite, ferrite and cementite ranges between 0.2 and 1.5%.

An antimicrobial agent, benzalkonium chloride (BAC), was added to a chemically cured composite resin, and the antimicrobial benefits and physical properties of the modified composite were evaluated. BAC was added to Reliance Phase II composite to create modified composites with BAC concentrations ranging from 0.25 to 2.50 wt%. Specimen disks of the modified composite were incubated with Streptococcus mutans for 48 hours, and an agar disk diffusion assay was used to measure zones of bacterial inhibition. Larger disks were suspended in brain-heart infusion medium containing 2 x 10(4) colony-forming units/mL Streptococcus sobrinus (10 mL, 2 wt% sucrose, 24 hours) to measure bacterial adherence to the adhesive; adherent cells were removed from the surface with 1 N NaOH, and the optical density of the cells was measured at 550 nanometers. Traction hooks were bonded to bovine teeth with the modified composite, and tensile bond strength was evaluated with a universal testing machine. Diametral tensile stress was also measured. The modified composite samples showed that antimicrobial activity increased with higher BAC content; no antimicrobial activity was measured for the original compound in either the disk diffusion or the bacterial adherence test. There were no significant differences (P.05) in either tensile bond strength or diametral tensile stress among the modified composite groups and the original product. The incorporation of BAC in composite material added antimicrobial properties to the original compound without altering its mechanical properties.

Metformin-associated lactic acidosis (MALA) in the absence of other risk factors, is extremely rare. A 60-year-old male presented to the emergency department feeling tired and breathless for the preceeding 3 days. He had a 10 year history of type 2 diabetes mellitus (T2DM) and was receiving treatment with metformin. There was no history of fever, cough or orthopnoea. Physical examination was unremarkable. Arterial blood gas analysis showed an increased anion gap metabolic acidosis and raised lactate. Mild pre-renal impairment was also present. There was no evidence of sepsis, heart or liver failure, anaemia or history of alcohol abuse. He received intravenous fluids with resultant normalisation of renal function but lactate levels remained elevated and bicarbonate remained low. At this point a diagnosis of MALA was considered. Metformin was stopped and within 24 hours lactate and bicarbonate levels returned to normal limits. This case highlights the possibility of metformin-treated patients developing lactic acidosis in the absence of other risk factors. Any unwell patient taking metformin should undergo measurement of serum lactate and bicarbonate.

5-Hydroxytryptamine (serotonin, 5-HT) is a hormone and a neurotransmitter found in the central nervous system. The conformational flexibility of the alkyl side chains in 5-HT plays an important role in its binding to receptor sites. The FTIR spectra of 5-hydroxytryptamine in 14 solution and as a solid form were obtained in the range of 4000-400 cm(-1). Geometry optimization based on molecular mechanics (using MM + force field), semi-empirical quantum mechanical calculations (using AM1, PM3 and MINDO) and HF and B3LYP levels using the 321 G and 6-31 (d) basic sets were performed. The calculated geometric parameters were compared to the corresponding X-ray structure of 5-hydroxytryptamine. For the optimized structures by semi-empirical, ab initio and DFT calculations, vibrational spectra were also generated. The assignments of the observed bands corresponding to 5-HT were made on the basis of such calculation and the comparison with related molecules. (c) 2005 Elsevier B.V. All rights reserved.