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Tannin, after lignin, is one of the most abundant sources of natural aromatic biomolecules. It has been used and chemically modified during the past few decades to create novel biobased materials. This work intended to functionalize for the first time quebracho Tannin (T) through a simple phosphorylation process in a urea system. The phosphorylation of tannin was studied by Fourier transform infrared spectroscopy (FTIR), NMR, inductively coupled plasma optical emission spectroscopy (ICP-OES), and X-ray fluorescence spectrometry (XRF), while further characterization was performed by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX) and thermogravimetric analysis (TGA) to investigate the morphology, composition, structure, and thermal degradation of the phosphorylated material. Results indicated the occurrence of phosphorylation, suggesting the insertion of phosphate-containing groups into the tannin structure, revealing a high content of phosphate for modified tannin (PT). This elevated phosphorus content serves as evidence for the successful incorporation of phosphate groups through the functionalization process. The corresponding PT and T were employed as adsorbents for methylene blue (MB) removal from aqueous solutions. The results revealed that the Langmuir isotherm model effectively represents the adsorption isotherms. Additionally, the pseudo-second-order model indicates that chemisorption predominantly controls the adsorption mechanism. This finding also supports the fact that the introduced phosphate groups via the phosphorylation process significantly contributed to the improved adsorption capacity. Under neutral pH conditions and at room temperature, the material achieved an impressive adsorption capacity of 339.26 mg·g-1 in about 2 h.
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Azul de Metileno , Taninos , Urea , Azul de Metileno/química , Azul de Metileno/aislamiento & purificación , Taninos/química , Urea/química , Fosforilación , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificaciónRESUMEN
The presence of harmful substances such as dyes in water systems poses a direct threat to the quality of people's lives and other organisms living in the ecosystem. Orange G (OG) is considered a hazardous dye. The existing paper attempts to evaluate a low-cost adsorbent for the effective removal of OG dye. The developed adsorbent Polyaniline@Hydroxyapatite extracted from Cilus Gilberti fish Scale (PANI@FHAP) was elaborated through the application of the in situ chemical polymerization method to incorporate PANI on the surface of naturally extracted hydroxyapatite FHAP. The good synthesis of PANI@FHAP was evaluated through multiple techniques including X-ray diffraction (XRD), Scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM/EDS), Fourier Transforms Infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) coupled with thermal differential analysis (DTA) analysis. The results reveal a highly ordered disposition of PANI chains on FHAP, resulting in a well-coated FHAP in the PANI matrix. Furthermore, the presence of functional groups on the surface of PANI such as amine (-NH2) and imine (=NH) groups would facilitate the removal of OG dye from contaminated water. The adsorption of OG onto PANI@FHAP was conducted in batch mode and optimized through response surface methodology coupled with box-Behnken design (RSM/BBD) to investigate the effect of time, adsorbent dose, and initial concentration. The outcomes proved that OG adsorption follows a quadratic model (R2 = 0.989). The kinetic study revealed that the adsorption of OG fits the pseudo-second-order model. On the other hand, the isotherm study declared that the Freundlich model is best suited to the description of OG adsorption. For thermodynamic study, the adsorption of OG is spontaneous in nature and exothermic. Furthermore, the regeneration-reusability study indicates that PANI@FHAP could be regenerated and reused up to five successive cycles. Based on the FTIR spectrum of PANI@FHAP after OG adsorption, the mechanism governing OG adsorption is predominantly driven by π-π interaction, electrostatic interaction, and hydrogen bonding interactions. The obtained results suppose that PANI@FHAP adsorbent can be a competitive material in large-scale applications.
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Compuestos de Anilina , Durapatita , Aguas Residuales , Contaminantes Químicos del Agua , Compuestos de Anilina/química , Durapatita/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Aguas Residuales/química , Colorantes/química , Compuestos Azo/química , Bencenosulfonatos/química , Animales , Escamas de Animales/química , Purificación del Agua/métodos , Cinética , Eliminación de Residuos Líquidos/métodosRESUMEN
Water pollution due to dyes in the textile industry is a serious environmental problem. During the finishing stage, Congo red (CR) dye, water-soluble, is released into wastewater, polluting the water body. This study explores the effectiveness of utilizing a composite composed of Safi raw clay and chitosan to remove an anionic dye from synthetic wastewater. The chitosan was extracted from crab shells. Its removal performance was compared to that of natural clay. Both the composite and raw clay were used to remove target pollutant. The effects of the chitosan load in the composite, size particles, initial dye concentration, contact time, pH, and temperature on the dye's elimination were tested in batch modes. The composite with 30% (w/w) of chitosan exhibited the highest dye removal. At pH 2, an adsorption capacity of 84.74 mg/g was achieved, indicating that the grafting of the polymer onto clay surface enhances its efficacity and stability in acidic environments. This finding was supported by characterization data obtained from X-ray diffraction (XRD), scanning electron microscopy (SEM), dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FT-IR) analyses. Under optimized conditions of 20 mg dose, pH 2, 30 min of reaction time, and 20 mg/L of dye concentration, about 92% of dye removal was achieved. The Langmuir isotherm model represents dye adsorption by the composite, while dye removal was controlled by pseudo-second-order model. Thermodynamic data of the adsorption (ΔH = +8.82 kJ/mol; ΔG <0) suggested that the dye adsorption was spontaneous and endothermic. The findings provide insights into the dye elimination by the adsorbent, indicating that the removal occurred via attractive colombic forces, as confirmed by density functional theory (DFT) analysis. Overall, the composite of natural clays and chitosan waste is a promising and innovative adsorbent for treating wastewater containing recalcitrant dyes.
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Quitosano , Arcilla , Colorantes , Rojo Congo , Contaminantes Químicos del Agua , Rojo Congo/química , Quitosano/química , Arcilla/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Colorantes/química , Adsorción , Aguas Residuales/química , Purificación del Agua/métodos , Silicatos de Aluminio/química , Concentración de Iones de HidrógenoRESUMEN
OBJECTIVE: To describe the prevalence of and between-center variations in care practices and clinical outcomes of moderate and late preterm infants (MLPIs) admitted to tertiary Canadian neonatal intensive care units (NICUs). STUDY DESIGN: This was a retrospective cohort study including infants born at 320/7 through 366/7 weeks of gestation and admitted to 25 NICUs participating in the Canadian Neonatal Network between 2015 and 2020. Patient characteristics, process measures represented by care practices, and outcome measures represented by clinical in-hospital and discharge outcomes were reported by gestational age weeks. NICUs were compared using indirect standardization after adjustment for patient characteristics. RESULTS: Among 25â669 infants (17% of MLPIs born in Canada during the study period) included, 45% received deferred cord clamping, 7% had admission hypothermia, 47% received noninvasive respiratory support, 11% received mechanical ventilation, 8% received surfactant, 40% received antibiotics in the first 3 days, 4% did not receive feeding in the first 2 days, and 77% had vascular access. Mortality, early-onset sepsis, late-onset sepsis, or necrotizing enterocolitis occurred in <1% of the study cohort. Median (IQR) length of stay was 14 (9-21) days among infants discharged home from the admission hospital and 5 (3-9) days among infants transferred to community hospitals. Among infants discharged home, 33% were discharged on exclusive breastmilk and 75% on any breastmilk. There were significant variations between NICUs in all process and outcome measures. CONCLUSIONS: Care practices and outcomes of MLPIs varied significantly between Canadian NICUs. Standardization of process and outcome quality measures for this population will enable benchmarking and research, facilitating systemwide improvements.
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Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Humanos , Canadá , Recién Nacido , Estudios Retrospectivos , Femenino , Masculino , Centros de Atención Terciaria , Edad Gestacional , Evaluación de Procesos y Resultados en Atención de Salud , Enfermedades del Prematuro/terapia , Enfermedades del Prematuro/epidemiologíaRESUMEN
The use of fish waste as a source material for the development of functional beads has significant potential applications in the fields of materials science and environmental sustainability. In this study, a biomaterial bead of chitosan was cross-linked with bio-hydroxyapatite (Bio-Hap/Cs) through the encapsulation process to create a stable and durable material. The beads are characterized using scanning electron microscopy combined with energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy, and X-ray diffraction techniques. The adsorption efficiency of Bio-Hap/Cs hydrogel beads was evaluated by using Orange G (OG) dye in both batch and recirculating column systems, and the effect of various parameters on the adsorption capacity was investigated. In the batch study, it was found that OG removal increased with an increasing pH and adsorbent dose. However, in the recirculating column system, a higher bed height and lower flow rate led to increased removal of the OG dye. The kinetic study indicated that the pseudo-second-order model provided a good description of OG adsorption onto Bio-Hap/Cs beads in both batch and recirculating processes, with a high coefficient correlation. The maximum adsorbed amounts are found to be 19.944 mg g-1 and 9.472 mg g-1 in batch and recirculating processes, respectively. Therefore, Bio-Hap/Cs hydrogel beads have demonstrated an effective and reusable material for OG dye remediation from aqueous solutions using recirculating adsorption processes.
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Alizarin Red S (ARS) is commonly utilized for dyeing in textile industry. The dye represents a refractory pollutant in the aquatic environment unless properly treated. To tackle this pollutant, the applicability of chitosan-clay composite (3C) for the ARS removal from textile wastewater was studied. Characterization studies were conducted on the synthesized adsorbent using Fourier transformation infrared (FT-IR), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) techniques. Optimized parameters such as adsorbent's dosage, pH, reaction time, and initial concentrations were tested in a batch system. Additionally, density functional theory (DFT) was calculated to understand the adsorption mechanism and the role of benzene rings and oxygen atoms in the ARS as electron donors. At the same initial concentration of 30 mg/L and optimized conditions of 50 mg of dose, pH 2, and 10 min of reaction time, about 86% of ARS removal was achieved using the composite. The pseudo-second-order kinetic was applicable to model a reasonable fitness of the adsorption reaction, while the Temkin model was representative to simulate the reaction with a maximum adsorption capacity of 44.39 mg/g. This result was higher than magnetic chitosan (40.12 mg/g), or pure chitosan (42.48 mg/g). With ΔH = 27.22 kJ/mol and ΔG<0, the data implied the endothermic and spontaneous nature of the adsorption process. Overall, this implies that the clay-chitosan composite is promising to remove target dye from contaminated wastewater.
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Antraquinonas , Quitosano , Contaminantes Ambientales , Contaminantes Químicos del Agua , Aguas Residuales , Quitosano/química , Arcilla/química , Espectroscopía Infrarroja por Transformada de Fourier , Adsorción , Cinética , Concentración de Iones de Hidrógeno , TermodinámicaRESUMEN
Water pollution by dyes and pesticides poses significant threats to our ecosystem. In this research, a visible-light ternary composite photocatalytic system was fabricated using graphene oxide (GO) by reducing with N2H4, modifying with KOH, and decorating with Ag/V2O5. The fabricated photocatalysts were characterized through FTIR, SEM, XRD, BET, PL, EDX, ESR, UV-vis spectroscopy, TGA, ESI-MS, and Raman spectroscopy. The point zero charge of the reduced and modified GO (RMGO/Ag/V2O5) was measured to be 6.7 by the pH drift method. This ternary composite was able to achieve complete removal of methyl orange (MO) and chlorpyrifos (CP) in solutions in 80 min under the optimum operation conditions (e.g., in terms of pollutant/catalyst concentrations, pH effects, and contact time). The role of active species responsible for photocatalytic activity was confirmed by scavenger analysis and ESR investigations. The potential mechanism for photocatalytic activity was studied through a fragmentation process carried out by MS analysis. Through nonlinear fitting of the experimental data, MO and CP exhibited the best fit results with the pseudo 1st-order kinetics (quantum yields of 1.07 × 10-3 and 2.16 × 10-3 molecules photon-1 and space-time yields of 1.53 × 10-5 and 2.7 × 10-5 molecules photon-1 mg-1, respectively). The structure of the nanomaterials remained mostly intact to support increased stability and reusability of the prepared photocatalysts even after 10 successive regeneration cycles.
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Compuestos Azo , Cloropirifos , Grafito , Plaguicidas , Colorantes/química , Ecosistema , LuzRESUMEN
While breastfeeding has long been an important, globally recognized aspect of population health, disparities exist across Canada. The Baby-Friendly Initiative (BFI) is a WHO/UNICEF best-practice program that helps ensure families receive evidence-based perinatal care and is associated with improved breastfeeding rates. However, <10% of hospitals in Canada are designated as 'Baby-Friendly'.The Breastfeeding Committee for Canada (BCC) aimed to increase the number of hospitals that moved towards BFI designation by implementing a National BFI Quality Improvement Collaborative Project. Key activities included (1) implementing and evaluating the BFI Project with 25 hospital teams across Canada and (2) making recommendations for scaling up BFI in Canada.As of December 2023, three hospitals in the BFI Project have attained designation and six have started the official process towards designation with the BCC. Breastfeeding initiation rates remained high and stable (>80%); however, breastfeeding exclusivity rates did not meet targets. All BFI care indicators improved across participating facilities. All skin-to-skin indicators improved, with rates of immediate and sustained skin-to-skin meeting targets of >80% for vaginal births. BFI care indicators of documented assistance and support with breastfeeding within 6 hours of birth, rooming-in and education about community supports also met target levels. Leadership buy-in, parent partner engagement and collaborative activities of workshops, webinars and mentoring with BFI Project leadership were viewed as valuable.This BFI Project demonstrated that hospitals could successfully implement Baby-Friendly practices in various Canadian settings despite challenges introduced by the COVID-19 pandemic. Indicators collected as part of this work demonstrate that delivery of Baby-Friendly care improved in participating facilities. Sustainability and scaling up BFI implementation in both hospitals and community health services across Canada through implementation of a BFI Coach Mentor Program is ongoing to enable continued progress and impact on breastfeeding and maternal-child health.
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Lactancia Materna , Mejoramiento de la Calidad , Femenino , Embarazo , Niño , Humanos , Canadá , Salud Infantil , Pandemias , Promoción de la Salud/métodosRESUMEN
This present study depicts the successful employment of fixed-bed column for total chromium removal from tannery wastewater in dynamic mode using sodium alginate-powdered marble beads (SA-Marble) as adsorbent. The SA-Marble composite beads prepared were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and Brunauer, Emmett and Teller (BET) method. The adsorption process performance of this bio-sorbent was examined in batches and columns for real effluent (tannery wastewater). After 90 min, the total chromium removal efficiency could be kept above 90% in the batch experiment. The adsorption kinetics fit better with the pseudo-second-order model, indicating the chemisorption process and the adsorption capacity of about 67.74 mg g-1 at 293 K (C0 = 7100 mg L-1) was obtained. Additionally, dynamic experiments indicate that the total chromium removal efficiency could be maintained above 90% after 120 min at 293 K and 60 min at 318 and 333 K; it's an endothermic but rapid process. The effects of two adsorption variables (Temperature and time) were investigated using central composite design (CCD), which is a subset of response surface methodology (total Cr, COD, sulfate, and total phosphorus percentage removal). This work paves a new avenue for synthesizing SA-Marble composite beads and provides an adsorption efficiency of total chromium removal from tannery wastewater.
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BACKGROUND AND PURPOSE: Despite the benefits of quality improvement (QI) training, there is a scarcity of information on QI teaching formats for undergraduate pharmacy education. The Evidence-based Practice for Improving Quality (EPIQ) workshop was evaluated as a teaching format for a group of multi-year undergraduate pharmacy students, assessing knowledge acquisition and learner reactions. EDUCATIONAL ACTIVITY AND SETTING: Using a convergent mixed-method analysis, 10-item pre- and post-workshop multiple-choice questionnaires measured students' knowledge acquisition of foundational QI concepts. A six-item pre- and post-workshop survey and a voluntary post-workshop focus group evaluated students' attitudes towards QI training and the teaching format. Mann-Whitney U non-parametric test was used to analyze the quantitative data, while thematic analysis was applied to analyze the qualitative data. FINDINGS: Twenty-nine pharmacy students participated in the workshop. There was a statistically significant improvement in pharmacy students' QI knowledge before and after participating in the workshop (77% vs. 86%, P = .008). The evaluation of the EPIQ teaching format resulted in three important findings: (1) undergraduate pharmacy students identified a QI learning need; (2) the EPIQ workshop effectively provided foundational QI literacy for all pharmacy student years using a "learning by sharing" methodology and pharmacy-specific case studies; and (3) interested students may benefit from an experiential elective to apply QI techniques. SUMMARY: The perceived value of QI training for pharmacy students using the EPIQ workshop was demonstrated: students expressed an interest in lifelong learning and a desire to pursue QI projects at school, during a clinical rotation, or at work.
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Estudiantes de Farmacia , Humanos , Curriculum , Mejoramiento de la Calidad , Aprendizaje , Práctica Clínica Basada en la EvidenciaRESUMEN
AIM: To develop a model for increasing the coverage of kangaroo mother care (KMC), which involved ≥8 h of skin-to-skin contact per day and exclusive breastfeeding, for small babies with birth weight < 2000 g in South Ethiopia. METHODS: A mixed methods study was conducted between June 2017 and January 2019 at four hospitals and their catchment areas. Iterative cycles of implementation, program learning and evaluation were used to optimise KMC implementation models. The study explored the community-facility continuum of care and assessed the proportion of neonates with a birth weight less than 2000 g receiving effective KMC. RESULTS: Three KMC implementation models were tested with Model 2 being the final version. This model included enhanced identification of home births, improved referral linkages, immediate skin-to-skin care initiation in facilities and early contact after discharge. These improvements resulted in 86% coverage of effective facility-based KMC initiation for eligible babies. The coverage was 81.5% at discharge and 57.5% 7 days after discharge. The mean age of babies at KMC initiation was 8.2 days (SD = 5.7). CONCLUSION: The study found that the KMC implementation model was feasible and can lead to substantial population-level KMC coverage for small babies.
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Método Madre-Canguro , Recién Nacido , Lactante , Femenino , Niño , Humanos , Peso al Nacer , Etiopía , Recién Nacido de Bajo Peso , Lactancia Materna/métodosRESUMEN
Neurodevelopmental challenges in children born very preterm are common and not improving. This study tested the feasibility of using Evidence-based Practice to Improve Quality (EPIQ), a proven quality improvement technique that incorporates scientific evidence to target improving language abilities in very preterm populations in 10 Canadian neonatal follow-up programs. Feasibility was defined as at least 70% of sites completing four intervention cycles and 75% of cycles meeting targeted aims. Systematic reviews were reviewed and performed, an online quality improvement educational tool was developed, multidisciplinary teams that included parents were created and trained, and sites provided virtual support to implement and audit locally at least four intervention cycles of approximately 6 months in duration. Eight of ten sites implemented at least four intervention cycles. Of the 48 cycles completed, audits showed 41 (85%) met their aim. Though COVID-19 was a barrier, parent involvement, champions, and institutional support facilitated success. EPIQ is a feasible quality improvement methodology to implement family-integrated evidence-informed interventions to support language interventions in neonatal follow-up programs. Further studies are required to identify potential benefits of service outcomes, patients, and families and to evaluate sustainability.
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Water contamination by pesticides is increasing dramatically due to population growth and the extensive use of pesticides in agriculture, leading to grave environmental and health concerns. Thus, efficient processes and the design and development of effective treatment technologies are required due to the enormous demand for fresh water. The adsorption approach has been widely used to remove organic contaminants such as pesticides because of its performance, less expense, high selectivity, and simplicity of operation compared to other treatment technologies. Among alternative adsorbents, biomaterials abundantly available for pesticide sorption from water resources have attracted the attention of researchers worldwide. The main objective of this review article is to (i) present studies on a wide range of raw or chemically modified biomaterials potentially effective in removing pesticides from aqueous media; (ii) indicating the effectiveness of biosorbents as green and low-cost materials for removing pesticides from wastewater; and (iii) furthermore, report the application of response surface methodology (RSM) for modeling and optimizing adsorption.
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BACKGROUND: Evidence-based Practice for Improving Quality (EPIQ) is a collaborative quality improvement method adopted by the Canadian Neonatal Network that led to decreased mortality and morbidity in very preterm neonates. The Alberta Collaborative Quality Improvement Strategies to Improve Outcomes of Moderate and Late Preterm Infants (ABC-QI) Trial aims to evaluate the impact of EPIQ collaborative quality improvement strategies in moderate and late preterm neonates in Alberta, Canada. METHODS: In a 4-year, multicentre, stepped-wedge cluster randomized trial involving 12 neonatal intensive care units (NICUs), we will collect baseline data with the current practices in the first year (all NICUs in the control arm). Four NICUs will transition to the intervention arm at the end of each year, with 1 year of follow-up after the last group transitions to the intervention arm. Neonates born at 32 + 0 to 36 + 6 weeks' gestation with primary admission to NICUs or postpartum units will be included. The intervention includes implementation of respiratory and nutritional care bundles using EPIQ strategies, including quality improvement team building, quality improvement education, bundle implementation, quality improvement mentoring and collaborative networking. The primary outcome is length of hospital stay; secondary outcomes include health care costs and short-term clinical outcomes. Neonatal intensive care unit staff will complete a survey in the first year to assess quality improvement culture in each unit, and a sample will be interviewed 1 year after implementation in each unit to evaluate the implementation process. INTERPRETATION: The ABC-QI Trial will assess whether collaborative quality improvement strategies affect length of stay in moderate and late preterm neonates. It will provide detailed population-based data to support future research, benchmarking and quality improvement. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT05231200.
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Recien Nacido Prematuro , Nacimiento Prematuro , Lactante , Femenino , Recién Nacido , Humanos , Mejoramiento de la Calidad , Alberta/epidemiología , Unidades de Cuidado Intensivo Neonatal , Edad Gestacional , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
The annual production of wastewater from the olive table industry poses a serious problem owing to its high organic matter load, which is highly concentrated in phenolic compounds (PCs) and inorganic materials. This research used adsorption to recover PCs from table olive wastewater (TOWW). Activated carbon was employed as a novel adsorbent. The activated carbon was obtained from olive pomace (OP) and activated using a chemical agent (ZnCl2). Fourier transform infrared spectroscopy analysis (FTIR), Brunauer-Emmett-Teller analysis (BET), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) were applied to characterize the activated carbon sample. To optimize the biosorption conditions of PCs (adsorbent dose (A), temperature (B), and time (C)), a central composite design (CCD) model was used. An adsorption capacity was 1952.34 mg g-1 for optimal conditions with an activated carbon dose of 0.569 g L-1, a temperature of 39 °C, and a contact time of 239 min. The pseudo-second-order and Langmuir models as kinetic and isothermal mathematical models were proved to be more appropriate for the interpretation of the adsorption phenomenon of PCs. PC recovery was performed in fixed-bed reactors. The results of the adsorption of PCs from TOWW by activated carbon could be an effective process at a low cost.
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The engineering of a novel biocomposite based on Cerastoderma edule shells doped with copper and alginate (Ce-Cu@Alg) forming hydrogel beads was used for batch and dynamic adsorption thiabendazole (TBZ) pesticide from water. The prepared biosorbent was analyzed by various characterization techniques such as scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller analysis (BET), and energy dispersive spectroscopy (EDS), thermogravimetric and differential analysis (TGA-DTA). The results of the TBZ batch biosorption by Ce-Cu@Alg composite showed that the Langmuir model was the most adequate to describe the adsorption process, with a maximum adsorption capacity value of 21.98 mg/g. Moreover, the adsorption kinetics were adjusted by the pseudo-second-order model. The optimal conditions determined by the RSM approach coupled with the CCD design were 100 ppm of initial TBZ concentration, a Ce-Cu@Alg beads dose of 6 g/L and a contact time of 180 min for maximum removal of 83.42%. On the other hand, the TBZ sorption on a fixed bed of Ce-Cu@Alg beads was effective at high column height, low effluent flow and low solution concentration. The Thomas model was best fitted to the kinetic data. This study shows the possibility of using this new hybrid biocomposite in the industrial sector to treat large effluent volumes.
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Cardiidae , Fungicidas Industriales , Contaminantes Químicos del Agua , Animales , Alginatos/química , Cobre/química , Hidrogeles/química , Fungicidas Industriales/análisis , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Adsorción , Agua/química , Cinética , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Heavy metal contamination has increased over the globe, causing significant environmental issues owing to direct and indirect releases into water bodies. As a result, metal removal from water entities must be addressed soon. Various adsorbents such as MOFs and chitosan have demonstrated promising results in water treatment. The present study prepared a composite material (chitosan-UiO-66-glycidyl methacrylate MOF) by a microwave-assisted method. The structure and morphology of the chitosan-MOF composite were studied using FE-SEM, EDX, XRD, BET, FT-IR, and TGA techniques. In addition, the adsorption of Pb(II) from aqueous solution onto the chitosan-MOF composite was analyzed in a batch study concerning pH, contact time, initial metal ion concentration, and adsorbent dosage. The composite has a large surface area of 867 m2/g with a total pore volume of 0.51 cm3/g and thermal stability of up to 400 [Formula: see text]. Following an analysis of the adsorption isotherms, kinetics, and thermodynamics, the Langmuir model showed an excellent fit with the adsorption data (R2 = 0.99) and chi-squared (X2 = 3.609). The adsorption process was a spontaneous exothermic reaction and the pseudo-second-order rate equation fitted the kinetic profile well. Moreover, the composite is recyclable, retaining 83.45% of its removal effectiveness after 5 consecutive cycles, demonstrating it as a sustainable adsorbent for metal recovery. This study introduces a novel synthesized composite with enhanced recyclability and a higher potential for eliminating pollutants from industrial wastewater.
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Quitosano , Contaminantes Químicos del Agua , Purificación del Agua , Quitosano/química , Plomo , Espectroscopía Infrarroja por Transformada de Fourier , Adsorción , Microondas , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de Hidrógeno , Purificación del Agua/métodosRESUMEN
A magnetic nanocomposite of tungsten and vanadium was employed as a catalyst for the mitigation of water contaminants, including a carcinogenic dye (Congo red, CR), a widely used pesticide (glyphosate), and the bacterial strain Escherichia coli. Additionally, it was subjected to several characterization techniques. X-ray diffraction spectroscopy examination validated the synthesized nanoparticles' crystalline nature, and scanning electron microscopy and energy-dispersive X-ray analysis were employed to examine the morphology and elemental composition of the catalyst. The use of thermogravimetric analysis enabled the elaboration of the thermal behavior of tungsten sulfide-vanadium decorated with Fe2O3 nanoparticles. The experiments were conducted under visible light conditions. The highest levels of photodegradation of 96.24 ± 2.5% for CR and 98 ± 1.8% for glyphosate were observed following a 180 min exposure to visible light at pH values of 6 and 8, respectively. The quantum yields for CR and Gly were calculated to be 9.2 × 10-3 and 4.9 × 10-4 molecules photon-1, respectively. The findings from the scavenger analysis suggest the involvement of hydroxyl radicals in the degradation mechanism. The study evaluated the inhibition of E. coli growth when exposed to a concentration of 0.1 g/10 mL of the photocatalyst, utilizing a 1 mL sample of the bacterial strain. The successful elimination of CR and glyphosate from water-based solutions, along with the subsequent antibacterial experiments, has substantiated the efficacy of the photocatalyst in the field of environmental remediation.
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This article aims to provide guidance to health care workers for the provision of basic and advanced life support to children and neonates with suspected or confirmed coronavirus disease 2019 (COVID-19). It aligns with the 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular care while providing strategies for reducing risk of transmission of severe acute respiratory syndrome coronavirus 2 to health care providers. Patients with suspected or confirmed COVID-19 and cardiac arrest should receive chest compressions and defibrillation, when indicated, as soon as possible. Because of the importance of ventilation during pediatric and neonatal resuscitation, oxygenation and ventilation should be prioritized. All CPR events should therefore be considered aerosol-generating procedures. Thus, personal protective equipment (PPE) appropriate for aerosol-generating procedures (including N95 respirators or an equivalent) should be donned before resuscitation, and high-efficiency particulate air filters should be used. Any personnel without appropriate PPE should be immediately excused by providers wearing appropriate PPE. Neonatal resuscitation guidance is unchanged from standard algorithms, except for specific attention to infection prevention and control. In summary, health care personnel should continue to reduce the risk of severe acute respiratory syndrome coronavirus 2 transmission through vaccination and use of appropriate PPE during pediatric resuscitations. Health care organizations should ensure the availability and appropriate use of PPE. Because delays or withheld CPR increases the risk to patients for poor clinical outcomes, children and neonates with suspected or confirmed COVID-19 should receive prompt, high-quality CPR in accordance with evidence-based guidelines.