Photocatalytic activation of persulfate (PS) has recently been considered an effective and environmentally friendly approach for antibiotic decomposition due to its high treatment efficiency, low ...energy consumption, and high reliability. The development of safe and high-performance catalysts is important for PS-based advanced oxidation processes. In this study, a CuFe-layered double hydroxide (LDH) coated graphene oxide (CuFe-LDH/GO) composite was constructed as a photocatalyst for trimethoprim (TMP) decomposition. The CuFe-LDH/GO catalyst was prepared via the co-precipitation method and characterized through Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), and X-ray electron microscopy (XPS) techniques. Characterization results revealed that GO was entirely covered by LDH platelets which also kept its hydrotalcite structure in the as-prepared nanocomposite. The average crystallite size of CuFe-LDH/GO was 28.22 nm. The results confirmed that CuFe-LDH/GO exhibited excellent performance for the PS activation with a TMP removal efficiency of 90.8% under UV-light irradiation. Compared with pristine CuFe-LDH, the rate constant of TMP degradation of CuFe-LDH/GO was doubled. The results also indicated that acidic and alkaline conditions were not favorable for TMP degradation, and the catalytic activity of the used photocatalyst has not decreased significantly after 720 h of continuous recycling. Overall, CuFe-LDH/GO could be a promising photocatalyst for the treatment of wastewater containing antibiotics.
General scheme for the formation of CuFe-LDH/GO nanocomposite. Display omitted
•CuFe-LDH/GO was successfully synthesized via the co-precipitation method.•CuFe-LDH/GO was used as an effective activator for persulfate in TMP degradation.•The composite exhibited high catalytic activity for TMP removal under UV irradiation.•Acidic and alkaline conditions were not favorable for TMP decomposition.
Various articles have been written about MOFs, which are organic-inorganic polymer structures that are unique in three-dimensional porosity, crystalline structure, and their ability to adsorb cadmium ...ion pollutants from aqueous solutions. These materials possess active metal sites, highly porous structures, high specific surfaces, high chemical functionality, and porous topologies. It is necessary to study adsorption kinetics, isotherms, and mechanisms in order to better understand the adsorption process. Adsorption kinetics can provide information about the adsorption rate and reaction pathway of adsorbents. Adsorption isotherms analyze the possibility of absorbances based on the Gibbs equation and thermodynamic theories. Moreover, in practical applications, knowledge of the adsorption mechanism is essential for predicting adsorption reactions and designing MOFs structures. In this review, the latest suggested adsorption mechanisms, kinetics, and isotherms of MOFs-based materials for removing cadmium ions are presented. A comparison is then conducted between different MOFs and the mechanisms of cadmium ion removal. We also discuss the future role of MOFs in removing environmental contaminants. Lastly, we discuss the gap in research and limitations of MOFs as adsorbents in actual applications, and probable technology development for the development of cost-efficient and sustainable MOFs for metal ion removal.
In this study, natural core-shell structure activated carbon beads (ACBs) from Litsea glutinosa seeds were successfully produced, characterized, and applied for adsorption of methylene blue (MB). The ...ACBs were prepared using single-step carbonization-activation with NaHCO3 at the optimized activation temperature, time, and activating agent concentration of 450 °C, 60 min, and 5%, respectively. Batch experiments were performed to determine the optimum adsorption conditions, suitable kinetic and isotherm models, and thermodynamic parameters for the adsorption of MB onto ACBs. The results showed that the ACBs were displayed as highly porous natural core-shell spheres with a diameter of about 5 mm. The adsorption of MB dye on ACBs was a spontaneous endothermic process, followed the Langmuir isotherm and the pseudo-second-order kinetic models with the rate-controlling step of both external diffusion and intra-particle diffusion. At the optimum conditions (pH of 9, the contact time of 10 h, the temperature of 40 °C, and an adsorbent dosage of 6 g/L), the maximum adsorption capacity reached 29.03 mg/g. The thermal method turned out to be more suitable for regenerating ACBs compared to the chemical method. The ACBs exhibited high reusability and stability, its adsorption efficiency could maintain more than 90% after five consecutive cycles of use. The electrostatic attraction, π–π interaction, hydrogen bonding, and pore-filling were identified as primary contributions to the adsorption mechanism. The overall results revealed that the ACBs could be used as a potential adsorbent for removing MB from water media.
Display omitted
•The Litsea glutinosa seeds were utilized to prepare activated carbon beads (ACBs).•The ACBs were presented as highly porous spheres with the core-shell structure.•The adsorption properties of the ACBs toward methylene blue were investigated.•The possible adsorption mechanism and reusability of the ACBs were clarified.•The ACBs exhibited high adsorption ability and excellent reusability.
Fluorescence in situ hybridization (FISH) is a powerful single-cell technique for studying nuclear structure and organization. Here we report two advances in FISH-based imaging. We first describe the ...in situ visualization of single-copy regions of the genome using two single-molecule super-resolution methodologies. We then introduce a robust and reliable system that harnesses single-nucleotide polymorphisms (SNPs) to visually distinguish the maternal and paternal homologous chromosomes in mammalian and insect systems. Both of these new technologies are enabled by renewable, bioinformatically designed, oligonucleotide-based Oligopaint probes, which we augment with a strategy that uses secondary oligonucleotides (oligos) to produce and enhance fluorescent signals. These advances should substantially expand the capability to query parent-of-origin-specific chromosome positioning and gene expression on a cell-by-cell basis.
This paper explores the complex landscape of smart tourism, investigating the implications of technology and data for sustainable growth within the tourism industry. Understanding the nuanced ...interplay between smart tourism initiatives and sustainability has become critical as the sector undergoes a paradigm shift driven by technological advancements. The paper contextualizes the emergence of smart tourism, unraveling the pivotal role of technology and data in transforming industry dynamics. Through comprehensive analysis, it examines how cutting-edge technologies including artificial intelligence, big data analytics, and the Internet of Things shape diverse aspects of tourism, from customer experience to operational efficiency. Additionally, it synthesizes evidence on the benefits of smart tourism for enhancing efficiency, sustainability, inclusiveness, experiential quality, and competitiveness across the sector. In conclusion, it contemplates future applications while underscoring the need for a balanced integration of technology and data to realize the promise of smart tourism. Further research on emerging applications, challenges, and best practices is highlighted to guide destinations towards this technology-enabled yet sustainable future.
This study examines the influence of empowerment leadership on employee loyalty under the mediating roles of employee trust and job satisfaction among medical staff at the private healthcare system. ...The investigation was conducted by surveying 374 doctors, nurses, and other medical staffs within 19 cities/provinces in the south of Vietnam. The SmartPLS software was used to conduct the partial least squared structural equation modeling (PLS-SEM) technique. The findings from the PLS-SEM analysis reveal that empowerment leadership has a direct positive influence on the employee loyalty to the organization of medical staff as well as a positive impact on intermediate variables such as employee trust and employee job satisfaction. On the other hand, the intermediate variables employee trust and employee job satisfaction also have a positive impact on the employee loyalty toward the organization. This research not only contributes to the existing body of knowledge by evaluating the relationship between employee trust, empowerment leadership, job satisfaction, and employee loyalty but also offers valuable recommendations for the management board of private healthcare organizations in southern Vietnam.
•NiO/PPy hybrid films synthesized by simple vapour-phase polymerization.•NiO/PPy ratios obtained by regulating FeCl3 oxidant contents on NiO-nanoparticles.•NiO/PPy hybrid films having high sensing ...performance of response, selectivity, and reversibility to NH3 gas.•Experimental results verified the existence of NiO/PPy hybrid structure.
In this work, NiO/PPy hybrid nanostructured films were fabricated by chemical vapor-phase polymerization using NiO nanoparticles films drop-coated FeCl3 oxidant on Al2O3 substrates. The NiO nanoparticles with a size of about 20 nm were synthesized by a hydrothermal method. Different ratios between NiO and PPy in the NiO/PPy hybrid films were modified by regulating FeCl3 oxidant content when using FeCl3 solutions with concentrations of 0.15, 0.2, 0.4, 0.8, and 1.5 M. X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, and Raman scattering spectroscopy were used to analyze specific material characteristics of these films. The gas-sensing performance of the films was examined by exploring their resistances responding to NH3, NO2, H2, CO, and relative humidity at an operating temperature range from 25 to 110 °C. The NiO/PPy hybrid films presented to have a very high sensitivity to NH3 gas in comparison to the non-hybrid films based on only NiO or PPy. The highest sensitivity to NH3 gas (the sensing response S = 246.6 % for 350 ppm at 25 °C) was found for the NiO/PPy film with the used 0.2 M FeCl3 oxidant solution. The gas-sensing performance of the NiO/PPy films was suggested by the main contribution of the hybrid nanostructure between NiO nanoparticles and PPy.
One of the current directions for sustainable development is to use waste resources to create materials that reduce environmental pollution. In this study, multi-walled carbon nanotubes (MWCNT) and ...their oxygen-functionalized forms (HNO3/H2SO4-oxidized MWCNT, NaOCl-oxidized MWCNT, and H2O2-oxidized MWCNT) were first synthesized from activated carbon (AC) derived from rice husk waste. A comprehensive comparison of the morphological and structural properties of these materials was conducted using FT-IR, BET, XRD, SEM, TEM, TGA, Raman spectroscopy, and surface charge analysis. The morphology study suggests that the synthesized MWCNTs have an average outer and inner diameter of about 40 and 20 nm, respectively. Additionally, the NaOCl-oxidized MWCNT possesses the largest interspaces between nanotubes, while the HNO3/H2SO4-oxidized CNT has the most oxygen-functional groups, including –COOH, (Ar)-OH, and C–OH. The adsorption capacities of these materials were also compared for the removal of benzene and toluene. Experimental results have shown that while porosity is the primary factor governing the benzene and toluene adsorption onto AC, functionalization degree and surface chemical characteristics are the determining factors in the adsorption capacity of the as-prepared MWCNTs. The adsorption capacity of these aromatic compounds in an aqueous solution increases in the following order: AC < MWCNT < HNO3/H2SO4-oxidized MWCNT < H2O2-oxidized MWCNT < NaOCl-oxidized MWCNT, and in all cases, toluene is more readily adsorbed than benzene under similar adsorption conditions. Wherein the uptake of both pollutants by the prepared adsorbents in this study is best described by the Langmuir isotherm and obeys the pseudo-second-order kinetic model. The adsorption mechanism was discussed in a detailed manner.
Display omitted
•AC, MWCNT, and oxidized MWCNTs are synthesized from rice husk waste.•Oxidized-MWCNTs were used as effective sorbents for benzene and toluene removal.•The highest functionalization degree belongs to MWCNT oxidized with NaOCl.•Supermicroporous structure limits the aromatic compounds adsorption onto AC.•π-π interaction is the main mechanism of the aromatic compounds uptake onto MWCNT.
Pesticides are a large group of pristine organic contaminants, which are widely discharged into environmental water due to agricultural activities. Hence, extraction, determination, and removal of ...pesticides from water resources are necessary for human health. In this study, novel adsorbent was developed based on three-dimensional magnetic graphene coated with gold nanoparticles (3D-MG@AuNPs) for extraction of chlorpyrifos, dicrotophos, fenitrothion, and piperophos as four specific organophosphorus pesticides (OPPs) from wastewater and tap water samples. The proposed nanocomposite was characterized; FTIR and EDX are performed for the expected functional groups and elemental analysis, SEM showed the unique and spherical AuNPs are well dispersed over graphene sheets. In this investigation, the important parameters that have effect on the extraction efficiency, including the desorbing solvent, desorbing solvent volume, vortex time, the extraction time, adsorbent dosage, pH of sample solutions, and salt effect were evaluated. In conclusion, the measured amounts of the chosen OPPs were determined using the gas chromatography microelectron capture (μECD-GC) method. Limits of quantification (S/N ratio of 10) and detection (S/N ratio of 3) were attained at concentrations of 0.26–0.43 μg.L−1 and 0.08–0.14 μg.L−1, respectively. According to the results of the investigations, the synthesized 3D-MG@AuNPs did not require any complicated sample preparation methods; therefore, it is a very good choice for solid magnetic phase extraction studies.
Display omitted
•3D-MG@AuNPs was used for removal of organophosphate pesticides.•The effecting parameters for removal of pesticides were evaluated.•With a high reusability, the nanoparticles worked after 25 times extraction.•The LOD (0.08–0.14 μg L−1) and LOQ (0.26–0.43 μg L−1) was achieved.
Purpose: This research investigates the role of employee trust and job satisfaction in the relationship between organizational culture and employee loyalty. Design/methodology/approach: The study was ...conducted among 355 healthcare professionals working in a private healthcare system in southern cities of Vietnam, including doctors, nurses, and other medical staff. The research method employed was partial least squared structure equation modeling (PLS-SEM) with SmartPLS software for data analysis. Findings: The findings indicate that organizational culture has a direct positive impact on employee loyalty and also affects employee trust and job satisfaction positively. Furthermore, employee trust and job satisfaction act as intermediaries and positively influence employee loyalty toward the organization. Research limitations/implications: The research acknowledges the limitation of the limited sample size and encourages further exploration of these relationships in other contexts. In addition, this study provides valuable insights for the management board of private healthcare organizations in southern cities of Vietnam on how to improve employee loyalty by cultivating a positive organizational culture, promoting employee trust, and enhancing job satisfaction. Originality/value: Overall, this research contributes significantly to the existing literature by examining the interplay between employee trust, organizational culture, job satisfaction, and employee loyalty.
PDF
