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Water splitting using solar light and an efficient photocatalyst is one of the new methods of hydrogen production that has attracted much attention today because of its importance in the energy crisis. Hence, a composite material containing molybdenum disulfide (MoS2) and g-C3N4 was synthesized and used in the photocatalytic process. For this purpose, in the first instance, the photocatalytic activity of MoS2/g-C3N4 was confirmed by the decolorization pathway of Rhodamine B (Rh B) under visible light irradiation. Then, MoS2/g-C3N4 was carefully identified by SEM, XRD, PL, UV–Vis, EDS, and FT-IR analysis. Results of characteristic peaks and composite surface morphology confirm that the structural integrity of the primary photocatalyst sample was intact after combination with MoS2 despite chemical interactions. The Brunner–Emmet–Teller (BET) surface area, total per valume, and average pore diameter of the sample are close to 15 m2g−1, 0.07 cm3g−1, and 19.5 nm, respectively. Then, the hydrogen production process under solar light was simulated using MoS2/g-C3N4 photocatalyst and the Production rate was measured using a gas chromatography system (GC). In addition, the Eosin-Y dye solution is also used as a sensitizer to increase the photocatalyst activity under visible light. The g-C3N4/MoS2-Triethanolamine (TEOA) mixture showed the best quantum efficiency when compared to all other sacrificial agents. Investigation of the factors affecting the catalyst activity showed that the parameters of exposure time, the concentration of photocatalyst, and triethanolamine (TEOA) percent used as a sacrificial agent affect water-splitting reaction efficiency. Further measurements showed that the highest hydrogen production rate of 1905 µmol g−1 h−1 is accessible. Accordingly, the g-C3N4 composite with MoS2 can be a promising photocatalyst for high-efficiency water splitting. Besides, the photocatalytic mechanism is demonstrated to well-fit into the S-scheme pathway with apparent evidence. [ABSTRACT FROM AUTHOR]

In this research, new magnetic nanocomposites that consist of NH2-MIL53 (Al) and Fe3O4 nanoparticles functionalized with cysteine were synthesized and characterized. The application of these nanocomposites was investigated to remove lead ions from the wastewater model. The concentration of metal ions was measured by the utilization of flame atomic absorption spectroscopy (FAAS). Also, XRD, SEM, EDX, and FTIR instruments were used to identification and characterization of the synthesized nanocomposites. The effect of operating parameters such as; pH, contact time and adsorbent dosage were investigated on lead removal. The synthesized nanocomposite showed great potential for lead removal. The maximum adsorption capacity of the nanocomposite was about 361.53 mg/g. Adsorption kinetic parameters well fitted with the pseudo-second order kinetic model. The reusability test of the synthesized magnetic absorbent showed good adsorption efficiency for at least three consecutive cycles. [ABSTRACT FROM AUTHOR]

Background From a clinical perspective, it is essential to know the microbial safety of fermented dairy products. Doogh and kashk are fermented dairies. These products are used by millions of people but their microbial qualities are unknown. Shiga toxin producing Escherichia coli (STEC) is one of the most commonly detected pathogens in the cases of food poisoning and food-borne illnesses. The present investigation was carried out in order to study the molecular characterization and antimicrobial resistance properties of STEC strains isolated from fermented dairy products. Methods Six hundred fermented dairy samples were collected and immediately transferred to the laboratory. All samples were cultured immediately and those that were E. coli-positive were analyzed for the presence of O157 , O26, O103, O111, O145, O45, O91, O113, O121 and O128 STEC serogroups, tetA, tetB, blaSHV, CITM, cmlA, cat1, aadA1, dfrA1, qnr, aac (3)- IV, sul1 and ereA antibiotic resistance genes and stx1, stx2, eaeA, ehly, cnf1, cnf2, iutA, cdtB, papA, traT, sfaS and fyuA virulence factors using PCR. Antimicrobial susceptibility testing was performed also using disk diffusion methodology with Mueller-Hinton agar. Results Fifty out of 600 (8.33%) dairy samples harbored E. coli. In addition, yoghurt was the most commonly contaminated dairy. O157 (26%) and O26 (12%) were the most commonly detected serogroups. A significant difference was found between the frequency of Attaching and Effacing E. coli and Enterohaemorrhagic E. coli (P <0.05). Stx1 (44%), eae (36%), papA (32%) stx2 (30%), and ehly (28%) were the most commonly detected virulence factors. The genes encode resistance against tetracycline (tetA and tetB) (76% and 70%, respectively), cephalothin (blaSHV) (38%), ampicillin (CITM) (36%) and gentamicin (aac (3)-IV) (32%) were the most commonly detected. High resistance levels to tetracycline (84%), penicillin (46%), ampicillin (38%) and streptomycin (36%) were observed. Conclusion Fermented dairy products can easily become contaminated by antibiotic resistant STEC strains. Our findings should raise awareness about antibiotic resistance in Iran. Clinicians should exercise caution when prescribing antibiotics, especially in veterinary treatments. [ABSTRACT FROM AUTHOR]

Heating a mixture of isatoic anhydride, amines, and N,N′-dialkyl carbodiimides under solvent-free conditions provided novel 3-alkyl-2-(alkylamino)quinazolin-4(3H)-one derivatives for the first time. The products were obtained in moderate to good yields without formation of any by-products. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications® to view the free supplemental file. [ABSTRACT FROM AUTHOR]

We present experimental results showing the correlation between the internal electric field and the backswitching phenomenon in congruent lithium niobate. The large internal electric field, responsible for the offset of the hysteresis loop, is shown to have reoriented parallel to the new spontaneous polarization after two months at room temperature and is shown not to be the cause of backswitching. The reduction and recovery of the poling field after a backswitching event are presented, showing that the coercive field for the domains that were involved in the backswitching is significantly reduced, recovering to its nominal value after approximately 200 ms. These results indicate the presence of a fast component to the internal electric field which decays with a time constant of 50 ms. The dependence of backswitching on the impedance of the poling circuit is also shown. [ABSTRACT FROM AUTHOR]

Aim: Chemical injuries can potentially lead to the necrosis anterior segment of the eye, and cornea in particular. Inflammatory cytokines are the first factors produced after chemical ocular injuries. Inflammation via promoting the angiogenesis factor tries to implement the wound healing mechanism in the epithelial and stromal layer of the cornea., Methods: Narrative review., Results: In our review, we described the patterns of chemical injuries in the cornea and their molecular mechanisms associated with the expression of inflammatory cytokines. Moreover, the effects of inflammation signals on angiogenesis factors and CNV were explained., Conclusion: The contribution of inflammation and angiogenesis causes de novo formation of blood vessels that is known as the corneal neovascularization (CNV). The new vascularity interrupts cornea clarity and visual acuity. Inflammation also depleted the Limbal stem cells (LSCs) in the limbus causing the failure of normal corneal epithelial healing and conjunctivalization of the cornea.