In situ deposition of polyaniline onto sisal fibers and removal efficiency for chromium (VI) from aqueous solution: Structure and adsorption studies

In the present study, polyaniline was coated on the surface of sisal fibers through in situ oxidative polymerization which was further characterized using FT‐IR, UV‐Vis, XRD, SEM and EDX instruments. The composite was tested to remove hexavalent chromium Cr(VI) from simulated wastewater on batch experimentas a function of contact time, solution pH, particle size, adsorbent dose and adsorbate dose. Peaks in the range of 1480‐1580 cm‐1 from FT‐IR spectra confirmed polyaniline is rich in amino polyfunctionalities. Another peak at 1160 cm‐1 proved introduction of polyaniline in the doped state. An EDX spectrum exhibits a characteristic peak of C, N, O and Cl atoms that verify deposition of polyaniline on the surface of sisal fibers. It was observed that adsorption of Cr(VI) is highly susceptible to pH change with the adsorption removal of 93.1% achieved at pH 4. Studies on adsorption reaction revealed adsorption process followed pseudo second orderkinetics confirming chemisorption as a rate determining step. The isotherm data were suitably fitted tothe Langmuir model with maximum adsorption capacity (qm) of 17.86 mg/g when all adsorption variables were optimized

Effect of triage training on the knowledge application and practice improvement among the practicing nurses of the emergency departments of the National Referral Hospitals, 2018; a pre-post study in Asmara, Eritrea

Abstract Background Triage starts at the front door of the Emergency Department (ED), and repeatedly performed by the responsible duty nurses with the aim of facilitating a timely and appropriate treatment of patients. A triage system called the Orotta Triage System was implemented in the emergency settings of the selected hospitals in 2006, with the emergency nurses trained to triage using the system. Since the introduction, a majority of nurses have been replaced by new untrained nurses. This study was conducted to assess the impact of an educational intervention on the triage nurses knowledge and performance. Methods A single group pre-posttest study design was performed in the adult EDs of the National Referral Eritrean Referral Hospitals, from January to July of 2018. All staff members in the ED were involved. Data collection tools utilized were, a self-administered knowledge assessing questionnaire and a practice observation checklist. Analysis was done in SPSS (version 22) using repeated measures ANOVA. Statistical significance level was set at P < 0.05. Results The mean knowledge scores at Time 1(prior to the intervention), Time 2 (following the intervention) and Time 3 (three month follow up) were 6.23 (SD = 2.29), 10.55 (SD = 1.79), and 9.39(SD = 2.67) respectively. During the pre-intervention phase, only one (3%) nurse was determined to have adequate knowledge. Two days post training (immediate post-intervention), the percentage possessing adequate knowledge increased to 39% but dropped back to 19% three months later. Mean knowledge difference scores (95% CI) of immediate post and pre-intervention (Diff. = 4.32, 1 95%CI: 3.08–5.56), three months later and pre-intervention (Diff. = 3.16, 95%CI: 1.71–4.62) and immediate post and three months later (Diff. = 1.16, 95%CI: 0.12–2.20) were found to be statistically significant. The median score of appropriate triage practice at pre-intervention (Md = 6, IQR = 3) was not significantly different (p = 0.053) from that at post-intervention (Md = 8, IQR = 5). Conclusion The level of triage knowledge and appropriate application was low among the emergency nurses prior to training. The training provided an initial improvement in knowledge, but no significant improvement in triage nursing performance. To optimize ED triage performance, appropriate, timely in-service training is required to ensure new staff are educated and experienced staff have their knowledge and skills refreshed

Nanomaterial-based optical colorimetric sensors for rapid monitoring of inorganic arsenic species: a review

Abstract Health concerns about the toxicity of arsenic compounds have therefore encouraged the development of new analytical tools for quick monitoring of arsenic in real samples with improved sensitivity, selectivity, and reliability. An overview of advanced optical colorimetric sensor techniques for real-time monitoring of inorganic arsenic species in the environment is given in this review paper. Herein, several advanced optical colorimetric sensor techniques for arsenite (As+3) and arsenate (As+5) based on doping chromogenic dyes/reagents, biomolecule-modified nanomaterials, and arsenic-binding ligand tethered nanomaterials are introduced and discussed. This review also highlights the benefits and limitations of the colorimetric sensor for arsenic species. Finally, prospects and future developments of an optical colorimetric sensor for arsenic species are also proposed. For future study in this sector, particularly for field application, authors recommend this review paper will be helpful for readers to understand the design principles and their corresponding sensing mechanisms of various arsenic optical colorimetric sensors

Characterization and Comparative Insights on Agave Americana and Agave Sisalana Leaf Fibers for High-Performance Applications

This work is focused on characterization and comparative study of agave americana and agave sisalana leaf fibers which can be used as potential alternative for synthetic fibers in engineering applications. Physico-chemical and mechanical properties of agave fibers were determined using different analytical procedures and instruments. According to the experimental data, the mean length and diameter of agave americana fibers were maximum of 1.76 m and 411 μm, respectively. Furthermore, the particular fibers possess larger amount of hemicellulose (17.4%) and moisture (~8%) which confirmed they are relatively hydrophilic in nature. Conversely, agave sisalana fibers possess larger amount of cellulose (66.4%) and ligni10.1080/10942912.2023.2246677n (~16%) compared to agave americana fibers. Meanwhile, SEM microstructure also proved surface of agave americana fibers was comparably rough, full of cracks and linings. EDAX analysis showed presence of significant amount of C and O, including trace amount of Ca, K, Si and S. Similarly, the semicrystalline agave americana fibers are longer and thicker possessing greater mean linear density (29.68 Tex). Agave sisalana fibers recorded maximum breaking tensile strength and elongation at break (512 MPa) and (~6%), respectively. These findings strongly suggested that agave fibers possess interesting features which can be used as potential reinforcement fibers for composite engineering

Polyaniline Deposition on the Surface of Cotton Fibers: Structural Studies, Swelling Behavior, and Water Absorption Properties

Polyaniline-modified natural fibers have been recognized as promising candidates for conductive clothes, UV protection, and electromagnetic interference shielding. Hence, the purpose of this study was to investigate the effect of surface deposition of cotton fibers using polyaniline via in situ polymerization, and preceding structural changes were further screened by FT-IR, UV-Vis, TGA, SEM/EDX, and conductivity in comparison with bare cotton fibers used as the control sample. Polyaniline was introduced on the surface of cotton fibers as a conductive form, which was confirmed by electrical conductivity (1.54 × 10−4 Scm−1) equivalent to semiconductor materials. Detection of particular peaks at NKα 0.379 keV and ClKα 2.621 keV from EDX analysis revealed the introduction of nitrogen and chlorine, respectively. Polyaniline deposition on the cotton surface was successful to introduce hydrophobic environment to the system to enhance resistance to water absorption meaningfully