An ionic liquid derived highly nitrogen-rich mesoporous carbon supported Au-Pd alloy was found to be an efficient and recyclable catalyst for the Ullmann coupling reaction of various aryl chlorides at room temperature in aqueous media.
A nano-fibrillated mesoporous carbon solid phase microextraction fiber was successfully prepared and used for the extraction of volatile organic compounds.
Background: Nowadays, though more attention is being paid to oral and dental hygiene all over the world, dental caries and periodontal diseases are increasing daily. We decided to study the effectiveness of natural toothbrush in prevention of dental caries and plaque formation. Methods: This analytic, semi-experimental clinical trial included 390 individuals. Subjects were divided into 3 groups: using natural toothbrush, using artificial toothbrush and using both natural and artificial toothbrush. The plaque index and DMFT was assessed at the beginning of the study until 1 year. ANOVA, Kruskal Wallis, LSD, Paired t-test, chi square, Fisher exact and Mc-Nemar tests were used for data analysis. Results: The plaque index in all three groups showed a mean reduction of 0.71. The mean DMFT in the samples before intervention was 8.38 ± 4.14 and increased to 9.1 ± 4.56. At the end of the study, the lowest plaque index was observed in the group using both the natural and artificial methods. During one year follow-up, the plaque index decreased 1.16, 0.83, and 0.21 degrees in the first, second and third groups. Conclusion: The increase in DMFT in the group that used artificial toothbrush was more than other groups. Thus, use of natural toothbrush leads to a decrease in growth rate of DMFT. Therefore natural toothbrush can be used for the cleaning of teeth and prevention of dental caries
Poly(ethersulfone) (PES) is one of the polymers most widely used for the fabrication of ultrafiltration or nanofiltration membranes in various applications, but its membrane suffers from fouling. In this study, preparation, characterization, and performance of PES nanocomposite membrane comprising peroxopolyoxometalate nanoparticles was studied to provide improved permeability and anti‐fouling properties. The high oxygen ratio of the PW4 nanoparticles could enhance the hydrophilicity of the membranes. The PW4 nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), energy dispersive X‐ray (EDX), and X‐ray diffraction analyses. The mixed matrix membranes were fabricated using a non‐solvent induced phase‐separation method. The fabricated membranes were characterized using atomic force microscopy, attenuated total reflection, SEM, EDX mapping, total average porosity, thermogravimetric analyze, and water contact angle experiments. The dye flux and rejection, pure water permeability and anti‐fouling properties of the membranes were investigated. All of the membranes blended by different contents of the PW4 nanoparticles presented better performance compared to the unmodified membrane. The filtration performance of the membranes in reactive green 19 (RG19) and reactive yellow 160 (RY160) dye separation showed that all of the PW4 blended membranes possessed dye rejection greater than 86% and 96% for RY160 and RG19, respectively. The reusability test using bovine serum albumin (BSA) protein and RG19 dye solutions in five cycle experiments presented good reproductivity of the PW4 blended membranes. The PES membrane containing 1 wt% of PW4 nanoparticles showed the highest flux recovery ratio (75%) as well as reduced irreversible fouling ratio (8%) through BSA protein filtration.
In this work, we study the three-dimensional AdS gravitational vacuum stars (gravastars) in the context of gravity’s rainbow theory. Then we extend it by adding the Maxwell electromagnetic field. We compute the physical features of gravastars, such as proper length, energy, entropy, and junction conditions. Our results show that the physical parameters for charged and uncharged states depend significantly on rainbow functions. Besides from charged state, they also depend on the electric field. Finally, we explore the stability of thin shell of three-dimensional (un)charged AdS gravastars in gravity’s rainbow. We show that the structure of thin shell of these gravastars may be stable and is independent of the type of matter.
83 percent of the world's population live in light-polluted areas, of which 40 percent live in places that are continuously lit by “ALAN (Artificial Light at Night)”. The light pollution caused by “ALAN” is growing day by day. Thus, the risk of environmental damages is growing in aquatic areas by increasing the “ALAN”. In this way this research, investigates the artificial light at night “ALAN” effect on Gambusia Holbrooke “mosquitofish” in Iran. To obtain the ALAN data, we relied on the information of the operational linear satellite scanning data related to the Metrological Defense Satellite Program (DMSP/OLS). the data provided by the DMSP satellite were belonged to 1992 and 2013 as images. The images were clipped by the geographical information systems (GIS), the images were classified into five classes based on the light pollution intensity. Afterward, the changes of light pollution by area and were calculated and reported. The aim of this research is to examined the effect of ALAN on the G. holbrooki. Two types of treatments were provided for G. holbrooki: control and ALAN treatments. In both treatments, fishes were kept for 60 days, and after that period, their shoaling and hiding behaviors were examined and recorded by a web camera. The results indicated that by increasing the ALAN, especially near the coastlines, the risk of harmful effects on G. holbrooki could be increased. The findings suggested that the ALAN might influence G. holbrooki behavior. The shoaling behavior of the ALAN treatments samples revealed that the time spent shoaling individually at night and during the day was decreased. As a result, in the hiding behavior experiment, G. holbrooki moved less at night after ALAN exposure but did not hide, indicating that the fish are unlikely to swim away or hide when exposed to light at night. As a result, they may be more vulnerable to predation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.