Synthesis of PANi nanoarrays anchored on 2D BiOCl nanoplates for photodegradation of Congo Red in visible light region

Photocatalytic processes have attained considerable attention of late years, especially for environmental remediation. Despite extensive research in this area, the need for safer, more efficient, and cost-effective processes has encouraged researchers to develop novel photocatalysis. However, the low active surface area and narrow bandgap limit their photocatalytic performances. In the present research, the 2D BiOCl sheets were successfully synthesized by a new hydrothermal method and decorated by PANi nanoarrays through in-situ oxidative polymerization of aniline. The UV�vis diffuse-re�ectance and photoluminescence spectroscopy revealed the synergistic effects between PANi nanoarrays and 2D BiOCl by enhancing the absorption in the visible light region and reduction of bandgap down to 2.9 eV. Furthermore, the morphology analysis showed the proper decoration of PANi nanoarrays on 2D BiOCl nanoplates. The synthesized nanocomposite with different weight loadings of PANi was taken to evaluate the decolorization efficiency of it. The result exhibited an optimum value of 88.35 at 60 min irradiation under visible light in the photodegradation of Congo Red (CR). Moreover, the probable photocatalytic mechanism for degradation of CR by PANi/BiCOl photocatalyst was proposed based on the scavenger experiments. The outcomes indicated that the PANi promoted the absorption intensity of the pure BiOCl in the visible region. To that, the well-arranged array and considerably high specific surface area of PANi could encourage the transfer of electrons witch generated by the photo to 2D BiOCl substrate and repel the recombination of electron-hole pairs. © 2019 The Korean Society of Industrial and Engineering Chemistr

Designed polyelectrolyte shell on magnetite nanocore for dilution-resistant biocompatible magnetic fluids.

Magnetite nanoparticles (MNPs) coated with poly(acrylic acid-co-maleic acid) polyelectrolyte (PAM) have been prepared with the aim of improving colloidal stability of core-shell nanoparticles for biomedical applications and enhancing the durability of the coating shells. FTIR-ATR measurements reveal two types of interaction of PAM with MNPs: hydrogen bonding and inner-sphere metal-carboxylate complex formation. The mechanism of the latter is ligand exchange between uncharged -OH groups of the surface and -COO(-) anionic moieties of the polyelectrolyte as revealed by adsorption and electrokinetic experiments. The aqueous dispersion of PAM@MNP particles (magnetic fluids - MFs) tolerates physiological salt concentration at composition corresponding to the plateau of the high-affinity adsorption isotherm. The plateau is reached at small amount of added PAM and at low concentration of nonadsorbed PAM, making PAM highly efficient for coating MNPs. The adsorbed PAM layer is not desorbed during dilution. The performance of the PAM shell is superior to that of poly(acrylic acid) (PAA), often used in biocompatible MFs. This is explained by the different adsorption mechanisms; metal-carboxylate cannot form in the case of PAA. Molecular-level understanding of the protective shell formation on MNPs presented here improves fundamentally the colloidal techniques used in core-shell nanoparticle production for nanotechnology applications

Musculoskeletal Disorders and Working Conditions Among Iranian Nursing Personnel

This study investigated the prevalence of musculoskeletal disorders (MSDs) and associations with organizational, physical and psychosocial working conditions among 520 nursing personnel in Tehran, Iran. The results of the cross-sectional study on aids and different educational levels of nurses showed that the participants experienced 88% of MSDs in at least one body region during the past 12 months. The 3 most prevalent body regions were the low back (65.3%), knee (56.2%) and neck (49.8%). The participants reported inflexible work schedule, poor quality of devices for transferring patients, overexertion and job dissatisfaction. Physical and psychosocial exposure revealed an elevated odds ratio (95% confidence interval) of MSDs. The results showed a combination of high physical and psychosocial work demands along with low control over the work which increased work-related stress and enhanced the risk of MSDs. This study findings could help to understand work-related MSDs among nursing personnel in a developing country where the work situation and sociocultural context differ from other countries

Crystal violet dye sorption over acrylamide/graphene oxide bonded sodium alginate nanocomposite hydrogel

The synthesis of acrylamide bonded sodium alginate (AM-SA) hydrogel and acrylamide/graphene oxide bonded sodium alginate (AM-GO-SA) nanocomposite hydrogel was successfully performed using the free radical method. The AM-SA and AM-GO-SA hydrogels were applied as composited adsorbents in crystal violet (CV) dye removal. The adsorption process experiments were performed discontinuously and the acquired data showed that the efficiency is more dependent on pH than other factors. The C–O, C[dbnd]O, and C[dbnd]C groups were detected in the produced hydrogels. The amount of surface area was computed to be 44.689 m2/g, 0.0392 m2/g, and 6.983 m2/g for GO, AM-SA, and AM-GO-SA nanocomposite hydrogel, respectively. The results showed that the experimental data follow the Redlich-Peterson isotherm model. Also, the maximum adsorption capacity of monolayer for CV dye adsorption was determined using AM-SA hydrogel and AM-GO-SA nanocomposite hydrogel 62.07 mg/g and 100.30 mg/g, respectively. In addition, the parameters RL, n, and E showed that the processes of adsorption of CV dye using both types of adsorbents are physical and desirable. Thermodynamically, the CV elimination was exothermic and spontaneous. Besides, thermodynamic results showed that the adsorption process is better proceeding at low temperatures. The experimental data followed a pseudo- second- order (PSO) kinetic model. Also, the Elovich model showed that AM-GO-SA nanocomposite hydrogel has more ability to absorb CV dye. Therefore, according to the obtained results, it can be stated that the produced hydrogels are efficient and viable composited adsorbent in removing CV dye from aqueous solution