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1.
Environ Res ; 216(Pt 2): 114525, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36243055

RESUMEN

1-butyl-3-methylimidazolium bis(triflouromethylsufonyl)imide functionalization to Na-X zeolite (IFZ) is the primary goal of this study in order to evaluate its ability to remove heavy metals (Cd2+), (Zn2+), dyes Rhodamine 6G (R6), and Alizarin Red S (AR) from aqueous streams. IFZ was thoroughly examined using analytical techniques XRD, BET, FE-SEM, and FTIR, to better understand its physical and chemical properties. The surface area and the volume of pores (IFZ; 19.93 m2/g, 0.0544 cm3/g) were reduced in comparison to the parent zeolite (Na-X; 63.92 m2/g, 0.0884 cm3/g). According to SEM, the crystal structure of the zeolite (Na-X) has not been significantly altered by XRD analysis. The mechanism, kinetics, isotherms, and thermodynamic properties of adsorption were all studied using batch adsorption experiments under various operating conditions. IFZ adsorbs dyes (AR; 76.33 mg/g, R6; 65.85 mg/g) better than metal ions (Cd2+; 30.68 mg/g, Zn2+; 41.53 mg/g) in acidic conditions. The Langmuir isotherm and pseudo-second order models were found to be the most accurate models for equilibrium data. Adsorption is endothermic and spontaneous, as revealed by the thermodynamics of the process. The IFZ can be used in three (Cd2+), two (Zn2+), four (AR), and five (R6) cycles of desorption and regeneration. For these reasons, IL-modified zeolite can be used to remove multiple types of pollutants from water in one simple step.


Asunto(s)
Líquidos Iónicos , Contaminantes Químicos del Agua , Zeolitas , Zeolitas/química , Adsorción , Cadmio/análisis , Colorantes/análisis , Contaminantes Químicos del Agua/análisis , Iones , Cinética , Termodinámica , Agua/química , Zinc/análisis , Concentración de Iones de Hidrógeno
2.
Int J Phytoremediation ; 25(2): 146-160, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35475946

RESUMEN

In this study, we used a simple and low-toxicity chemical treatment to make a carboxylate-functionalized dragon fruit peel powder (CF-DFPP) from dragon fruit peel to improve its capacity for adsorbing Rhodamine B (RhB) from an aqueous medium. Field Emission-Scanning Electron Microscopy/Energy-Dispersive X-ray (FE-SEM/EDX), point of zero charges (pHPZC), Brunauer-Emmett-Teller (BET), and Fourier Transform Infrared (FT-IR) analyses were performed to characterize the adsorbent materials. The adsorption performance and mechanism for the removal of RhB were examined. The kinetic, isotherm and thermodynamic parameters were employed to evaluate the adsorption mechanism. Compared to other models, the Langmuir isotherm and PSO kinetic models better defined the experimental data. CF-DFPP adsorbent exhibited a maximum adsorption efficiency of 228.7 mg/g at 298 K for RhB adsorption. Thermodynamic analysis revealed that the adsorption of RhB by CF-DFPP was spontaneous (ΔGo < 0) and exothermic (ΔHo < 0) nature of the process. Different eluting agents were used in desorption tests, and NaOH was revealed to have greater desorption efficiency (96.8%). Furthermore, regeneration examinations revealed that the biosorbent could effectively retain RhB, even after six adsorption/desorption cycles. These findings demonstrated that the CF-DFPP might be a novel material for removing RhB from an aqueous medium.


Asunto(s)
Frutas , Contaminantes Químicos del Agua , Polvos/análisis , Frutas/química , Adsorción , Espectroscopía Infrarroja por Transformada de Fourier , Biodegradación Ambiental , Termodinámica , Cinética , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno
3.
Int J Phytoremediation ; 24(2): 131-144, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34057865

RESUMEN

NOVELTY STATEMENT: In the modern era, dyes are inevitable and their surging usage leads to colossal contamination of aqueous streams, thereby threatening both the land and aquatic species. One among such dye is anionic Reactive Red 195 (RR 195), and traceable even at minute concentrations of aqueous streams, posing a severe threat to living species. Moreover, RR 195 is highly recalcitrant offering resistance to biodegradation due to the presence of an azo (-N=N-) group within its structure. Thus, there is a definite need to address the issue of eliminating RR 195 from industrial wastewater effluents. In lieu of this, the primitive objective of this study is to test the effectiveness of the natural adsorbent lotus leaf (Nelumbo nucifera) for the selective sorption of RR 195 from the aqueous stream. Although ample literature is available on the direct utilization of lotus leaf as adsorbent, yet no study was performed on the chemical modification (dimethylamine) of the aforementioned adsorbent. Hence, an attempt has been made in this direction to add a new sorbent into the adsorbents database.


Asunto(s)
Lotus , Nelumbo , Contaminantes Químicos del Agua , Adsorción , Compuestos Azo , Biodegradación Ambiental , Dimetilaminas , Concentración de Iones de Hidrógeno , Cinética , Naftalenosulfonatos , Hojas de la Planta/química , Polvos , Termodinámica , Contaminantes Químicos del Agua/análisis
4.
Int J Phytoremediation ; 23(9): 911-923, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33406890

RESUMEN

Aminated avocado seed powder (AASP)-an eco-friendly novel adsorbent has been used for the removal of Acid Yellow 17 (AY 17) and Amaranth (AMR) from an aqueous phase. The AASP (before and after adsorption) was systematically characterized by different analytical techniques such as FT-IR, FESEM, EDX, and N2 adsorption-desorption analysis. Non-linear form of various kinetic (PFO and PSO) and isotherm (Langmuir and Freundlich) models were used to examine the adsorption behavior of AY 17 and AMR onto AASP. The adsorption of AY 17 and AMR onto AASP was well illustrated by the PSO kinetic model and Langmuir isotherm models. At 303 K, the maximum adsorption capacities (obtained from the Langmuir) of the AASP for AY 17 and AMR was 42.7 and 89.2 mg/g, respectively. The AY 17 and AMR adsorption was strongly pH-dependent with an optimum pH value of 2.0. Activation energy was calculated as 12.3 and 16.3 kJ/mol for AY 17 and AMR respectively, suggesting physical adsorption. The positive values of ΔGo and ΔHo indicated that the adsorption process of AY 17 and AMR onto AASP was non-spontaneous and endothermic. The negligible loss of adsorption capacity and excellent regeneration of AASP were observed for the five cycles. Statement of novelty: The present research majorly focused on the synthesis of adsorbent from Avocado seed for the removal of Acid Yellow 17 and Amaranth anionic dyes from aqueous solution. Although the literature is available on direct seed powder as adsorbent, to the best of our knowledge, no chemical modified adsorbent synthesis was not available. Hence, to fill the gap in the literature, we chose the following study that significantly enhanced the adsorption efficiency of the selected anionic dyes.


Asunto(s)
Persea , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Biodegradación Ambiental , Colorantes , Concentración de Iones de Hidrógeno , Cinética , Polvos , Semillas , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Contaminantes Químicos del Agua/análisis
5.
Int J Phytoremediation ; 22(3): 267-278, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31464513

RESUMEN

The removal of Reactive Black 5 (RB5) using chemically modified banana peel powder (CMBPP) from aqueous solution was dealt with in the present investigation. Factors affecting the adsorption of RB5 (like pH solution, agitation speed, initial concentration of RB5, contact time and temperature) were investigated. FTIR, SEM-EDX, BET and Elemental analysis characterized the adsorbent material. Adsorption kinetic results evaluated by non-linear pseudo-second-order model was fitted well and showed good correlation with the experimental data than the pseudo-first-order model. The experimental equilibrium data evaluated by non-linear Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin equations and the experimental data were well described by the Langmuir isotherm model. Langmuir monolayer sorption capacity of RB5 onto CMBPP was observed at pH 3.0 (211.8 mg/g). The values of thermodynamic parameters revealed that the sorption process was feasible, spontaneous, endothermic, and physisorption in nature, i.e. (ΔG° <0, ΔH° > 0, and ΔS° > 0). Desorption studies reveal that the maximum recovery of RB5 when 0.1 M NaOH solution used as a desorbent. The CMBPP also exhibited excellent regeneration efficiency for the five cycles of successive adsorption-desorption. The results exposed that CMBPP could use as a prospective adsorbent material for the removal of RB5 from aqueous media.


Asunto(s)
Musa , Contaminantes Químicos del Agua , Adsorción , Biodegradación Ambiental , Concentración de Iones de Hidrógeno , Cinética , Naftalenosulfonatos , Estudios Prospectivos , Temperatura , Termodinámica
6.
J Med Internet Res ; 20(2): e39, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29396388

RESUMEN

Due to the increasing number of natural and man-made disasters, mass casualty incidents occur more often than ever before. As a result, health care providers need to adapt in order to cope with the overwhelming patient surge. To ensure quality and safety in health care, accurate information in pandemic disease control, death reduction, and health quality promotion should be highlighted. However, obtaining precise information in real time is an enormous challenge to all researchers of the field. In this paper, innovative strategies are presented to develop a sound information network using the concept of "witness sensors." To overcome the reliability and quality limitations of information obtained through social media, researchers must focus on developing solutions that secure the authenticity of social media messages, especially for matters related to health. To address this challenge, we introduce a novel concept based on the two elements of "witness" and "sensor." Witness sensors can be key players designated to minimize limitations to quality of information and to distinguish fact from fiction during critical events. In order to enhance health communication practices and deliver valid information to end users, the education and management of witness sensors should be further investigated, especially for implementation during mass casualty incidents and epidemic outbreaks.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Epidemias/estadística & datos numéricos , Testimonio de Experto/estadística & datos numéricos , Incidentes con Víctimas en Masa/psicología , Planificación en Desastres , Humanos , Reproducibilidad de los Resultados
7.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37631073

RESUMEN

A sequence of novel 1,4-dihydropyridines (DHP) and their hybrids was developed using a multicomponent strategy under environmentally benign conditions. In addition, computational studies were performed, and the ligand-protein interactions calculated in different bacteria and two fungal strains. Para-hydroxy-linked DHP (5f) showed the best binding energies of 3.591, 3.916, 8.499 and 6.895 kcal/mol against various pathogens used and other substances received a good docking score. The pathogen resistance potential of the synthesized targets against four bacteria and two fungi showed that whole DHP substances exhibit different levels of resistance to each microorganism. Gram-positive bacteria, which are highly sensitive to all molecules, and the MTCC-1884-encoded fungus strongly rejected the studied compounds compared to comparator drugs. In particular, the 5f candidate showed remarkable antimicrobial activity, followed by the substances 5a, 5b, 5j, 5k and 5l. Furthermore, MIC and MBC/MFC properties showed that 5f had a minimum bacterial concentration of 12.5 µg/mL against E. coli and against two fungal pathogens, with its killing activity being effective even at low concentrations. On the other hand, whole motifs were tested for their cytotoxic activity, revealing that the methoxy and hydroxy-linked compounds (5h) showed greater cytotoxic potency, followed by the two hydroxy linked compounds (5d and 5f). Overall, this synthetic approach used represents a prototype for future nature-favored synthesis methods and these biological results serve as a guide for future therapeutic drug research. However, the computer results play an important role in the further development of biological experiments.

8.
Int J Biol Macromol ; 246: 125675, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37414311

RESUMEN

In the present work, a novel Fe3O4-GLP@CAB was successfully synthesized via a co-precipitation procedure and applied for the removal of methylene blue (MB) from aqueous environment. The structural and physicochemical characteristics of the as-prepared materials were explored using a variety of characterization methods, including pHPZC, XRD, VSM, FE-SEM/EDX, BJH/BET, and FTIR. The effects of several experimental factors on the uptake of MB using Fe3O4-GLP@CAB were examined through batch experiments. The highest MB dye removal efficiency of Fe3O4-GLP@CAB was obtained to be 95.2 % at pH 10.0. Adsorption equilibrium isotherm data at different temperatures showed an excellent agreement with the Langmuir model. The adsorption uptake of MB onto Fe3O4-GLP@CAB was determined as 136.7 mg/g at 298 K. The kinetic data were well-fitted by the pseudo-first-order model, indicating that physisorption mainly controlled it. Several thermodynamic variables derived from adsorption data, like as ΔGo, ΔSo, ΔHo, and Ea, accounted for a favourable, spontaneous, exothermic, and physisorption process. Without seeing a substantial decline in adsorptive performance, the Fe3O4-GLP@CAB was employed for five regeneration cycles. Because they can be readily separated from wastewater after treatment, the synthesized Fe3O4-GLP@CAB was thus regarded as a highly recyclable and effective adsorbent for MB dye.


Asunto(s)
Nanopartículas , Psidium , Contaminantes Químicos del Agua , Adsorción , Polvos , Azul de Metileno/química , Alginatos/química , Hidrogeles , Fenómenos Magnéticos , Hojas de la Planta , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
9.
J Colloid Interface Sci ; 638: 39-53, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36731217

RESUMEN

The increasing consumption of room-temperature ionic liquids (RTILs) inevitably releases RTILs into the water environment, posing serious threats to aquatic ecology due to the toxicities of RTILs. Thus, urgent needs are necessitated for developing useful processes for removing RTILs from water, and 1-butyl-3-methylimidazolium chloride (C4mimCl), the most common RTIL, would be the most representative RTIL for studying the removal of RTILs from water. As advanced oxidation processes with hydrogen peroxide (HP) are validated as useful approaches for eliminating emerging contaminants, developing advantageous heterogeneous catalysts for activating HP is the key to the successful degradation of C4mim. Herein, a hierarchical structure is fabricated by growing Cu2S on copper mesh (CSCM) utilizing CM as a Cu source. Compared to its precursor, CuO@CM, this CSCM exhibited tremendously higher catalytic activity for catalyzing HP to degrade C4mim efficiently because CSCM exhibits much more superior electrochemical properties and reactive sites, allowing CSCM to degrade C4mim rapidly. CSCM also exhibits a smaller Ea of C4mim elimination than all values in the literature. CSCM also shows a high capacity and stability for activating HP to degrade C4mim in the presence of NaCl and seawater. Besides, the mechanistic investigation of C4mim elimination by CSCM-activated HP has also been clarified and ascribed to OH and 1O2. The elimination route could also be examined and disclosed in detail through the quantum computational chemistry, confirming that CSCM is a useful catalyst for catalyzing HP to degrade RTILs.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Agua , Cobre , Temperatura , Mallas Quirúrgicas , Peróxido de Hidrógeno/química
10.
Chemosphere ; 327: 138469, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36963579

RESUMEN

As sunscreens, benzophenones (BPs), are regarded as emerging contaminants, most of studies are focused on removal of 2-hydroxy-4-methoxybenzophenone (BP-3), which, however, has been employed for protecting skin. Another major class of BPs, which is used to prevent UV-induce degradation in various products, is completely neglected. Thus, this present study aims to develop a useful advanced oxidation process (AOP) for the first time to eliminate such a class of BP sunscreens from contaminated water. Specifically, 2,2',4,4'-Tetrahydroxybenzophenone (BP-2) would be focused here as BP-2 is intensively used in perfumes, lipsticks, and plastics for preventing the UV-induced degradation. As monopersulfate (MPS)-based AOP is practical for degrading emerging contaminants, a facile nanostructured cobalt-based material is then developed for maximizing catalytic activities of MPS activation by immobilizing Co nanoparticles onto carbon substrates. In particular, ZIF-67 is employed as a template, followed by the etching and carbonization treatments to afford the thorny nanobox of Co@C (TNBCC) with the hollow-nanostructure. In comparison to the solid (non-hollow) nanocube of Co@C (NCCC) from the direct carbonization of ZIF-67, TNBCC possesses not only the excellent textural features, but also superior electrochemical properties and highly reactive surfaces, making TNBCC exhibit the significantly higher catalytic activity than NCCC as well as Co3O4 in activating MPS to degrade BP-2. Mechanisms of BP-2 degradation are also elucidated and ascribed to both radical and non-radical routes. These advantageous features make TNBCC a useful catalyst of activating MPS in BP-2 degradation.


Asunto(s)
Protectores Solares , Agua , Agua/química , Carbono/química , Cobalto/química , Plásticos
11.
J Colloid Interface Sci ; 606(Pt 2): 929-940, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34487940

RESUMEN

While cobalt (Co) stands out as the most effective non-precious metal for activating monopersulfate (MPS) to degrade organic pollutants, Co nanoparticles (NPs) are easily aggregated, losing their activities. As many efforts have attempted to immobilize Co NPs on supports/substrates to minimize the aggregation issue, recently hollow-structured carbon-based materials (HSCMs) have been regarded as promising supports owing to their distinct physical and chemical properties. Herein, in this study, a special HSCM is developed by using a special type of ZIF (i.e., ZIF-L) as a precursor. Through one-step chemical etching with tannic acid (TA), the resultant product still remains leaf-like morphology of pristine ZIF-L but the inner part of this product becomes hollow, which is subsequently transformed to ultrafine Co-NP embedded hollow-structured N-doped carbon (CoHNC) via pyrolysis. Interestingly, CoHNC exhibits superior catalytic activities than CoNC (without hollow structure) and the commercial Co3O4 NPs for activating MPS to degrade phenol. The Ea value of phenol degradation by CoHNC + MPS was determined as 44.3 kJ/mol. Besides, CoHNC is also capable of effectively activating MPS to degrade phenol over multiple-cycles without any significant changes of catalytic activities, indicating that CoHNC is a promising heterogeneous catalyst for activating MPS to degrade organic pollutants in water.


Asunto(s)
Cobalto , Nanopartículas , Carbono , Fenol , Fenoles
12.
Medicine (Baltimore) ; 100(11): e24482, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33725935

RESUMEN

ABSTRACT: The purpose of this research is to analyze and introduce a new emergency medical service (EMS) transportation scenario, Emergency Medical Regulation Center (EMRC), which is a temporary premise for treating moderate and minor casualties, in the 2015 Formosa Fun Color Dust Party explosion in Taiwan. In this mass casualty incident (MCI), although all emergency medical responses and care can be considered as a golden model in such an MCI, some EMS plans and strategies should be estimated impartially to understand the truth of the successful outcome.Factors like on-scene triage, apparent prehospital time (appPHT), inhospital time (IHT), and diversion rate were evaluated for the appropriateness of the EMS transportation plan in such cases. The patient diversion risk of inadequate EMS transportation to the first-arrival hospital is detected by the odds ratios (ORs). In this case, the effectiveness of the EMRC scenario is estimated by a decrease in appPHT.The average appPHTs (in minutes) of mild, moderate, and severe patients are 223.65, 198.37, and 274.55, while the IHT (in minutes) is 18384.25, 63021.14, and 83345.68, respectively. The ORs are: 0.4016 (95% Cl = 0.1032-1.5631), 0.1608 (95% Cl = 0.0743-0.3483), and 4.1343 (95% Cl = 2.3265-7.3468; P < .001), respectively. The appPHT has a 47.61% reduction by employing an EMRC model.Due to the relatively high appPHT, diversion rate, and OR value in severe patients, the EMS transportation plan is distinct from a prevalent response and develops adaptive weaknesses of MCIs in current disaster management. Application of the EMRC scenario reduces the appPHT and alleviates the surge pressure upon emergency departments in an MCI.


Asunto(s)
Servicios Médicos de Urgencia/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Incidentes con Víctimas en Masa , Factores de Tiempo , Transporte de Pacientes/estadística & datos numéricos , Adolescente , Adulto , Polvo , Servicios Médicos de Urgencia/métodos , Explosiones , Femenino , Humanos , Masculino , Taiwán , Triaje/métodos , Triaje/estadística & datos numéricos , Adulto Joven
13.
J Hazard Mater ; 416: 125925, 2021 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492857

RESUMEN

SSZ-13 zeolite was successfully synthesized from coal bottom ash (CBA) upon hydrothermal treatment for selective sorption of Alizarin Red S (ARS) dye. The characterization of CBA, and SSZ-13 were performed using BET, SEM, FTIR, XRF, and XRD techniques. The optimal fusion ratio (CBA: NaOH) was identified as 1:3, resulting zeolite SSZ-13 with a specific surface area of 206.6 m2/g, compared to raw CBA (7.81 m2/g). The kinetics, isotherms, and thermodynamics of the ARS adsorption onto the SSZ-13, and CBA were assessed under various conditions. The results indicated that the adsorption phenomenon is optimal under acidic medium (pH = 2 for CBA, pH = 3 for SSZ-13); at ambient room temperature of 298 K; adsorbent dosage of 0.03 g, contact time of 120 min. Further, the equilibrium data fitted well to Langmuir isotherm (qe = 210.75 mg/g), following pseudo-second-order kinetics. Moreover, the chemisorption phenomenon is clearly described using Elovich kinetic model. Various thermodynamic parameters signifies the adsorption phenomenon is spontaneous, and endothermic in nature. Finally, regeneration studies revealed the sensitivity of SSZ-13 zeolite towards 0.1 M NaOH/EtOH eluent in recovery and the possibility of reuse to five successive adsorption/desorption cycles. Thus, hydrothermal treatment of CBA has potential in producing zeolites suitable to adsorption.


Asunto(s)
Contaminantes Químicos del Agua , Zeolitas , Adsorción , Aniones , Antraquinonas , Carbón Mineral , Ceniza del Carbón , Concentración de Iones de Hidrógeno , Cinética , Termodinámica
14.
Ground Water ; 58(1): 79-92, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30859561

RESUMEN

Drawdown data from independent pumping tests have widely been used to validate the estimated hydraulic parameters from inverse modeling or hydraulic tomography (HT). Yet, the independent pumping test has not been clearly defined. Therefore, the goal of this paper is to define this independent pumping test concept, based on the redundant or nonredundant information about aquifer heterogeneity embedded in the observed heads during cross-hole pumping tests. The definition of complete, moderate redundancy and high nonredundancy of information are stipulated using cross-correlation analysis of the relationship between the head and heterogeneity. Afterward, data from numerical experiments and field sequential pumping test campaigns reinforce the concept and the definition.


Asunto(s)
Agua Subterránea , Calibración , Modelos Teóricos , Tomografía , Tomografía Computarizada por Rayos X
15.
Int J Biol Macromol ; 146: 1100-1110, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31682857

RESUMEN

A novel, eco-friendly aminated chitosan Schiff's base (ACSSB@ZnO) was developed and utilized to remove MO from aqueous environment. The impact of different significant parameters, for example, pH (3-11), adsorbent dose (0.1-0.6 g), contact time (0-120 min), and temperature (303-323 K) have been explored by batch process. Kinetic data was illustrated by pseudo-second-order model and the isotherms fitted well with Langmuir isotherm model. The highest sorption capacity of ACSSB@ZnO was observed to be 111.11 mg/g at 323 K. Positive enthalpy and entropy values demonstrated that the MO adsorption procedure was an endothermic. Negative Gibbs free energy values implied the spontaneous nature of the adsorption system. Moreover, reusability experiments were studied and it can be regenerated by using NaOH as effluent.


Asunto(s)
Compuestos Azo/aislamiento & purificación , Quitosano/síntesis química , Colorantes/aislamiento & purificación , Bases de Schiff/síntesis química , Bases de Schiff/farmacología , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Aminación , Animales , Quitosano/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Células MCF-7 , Masculino , Ratones , Espectroscopía de Protones por Resonancia Magnética , Bases de Schiff/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Factores de Tiempo , Difracción de Rayos X , Óxido de Zinc/química
16.
Int J Biol Macromol ; 149: 127-139, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-31978476

RESUMEN

Uranium (U(VI)) is radioactive and the primary raw material in the production of nuclear energy. Hence the research associated with uranium removal gained a lot of importance because to reduce the threat of uranium contamination to ecology and its environment surroundings. Thus, economically as well as environmentally friendly sorbents with a good sorption capacity have to be acquired for the removal of U(VI) pollutants from the aqueous and polluted sea samples. In this study magnetic- Momordica charantia leaf powder impregnated into chitosan (m-MCLPICS) was prepared through the impregnation method. After preparation the adsorbent undergone through various characterizations such as BET, XRD, FTIR, SEM with elemental mapping, and VSM analysis. The specific surface area (93.12 m2/g), pore size (0.212 cm3/g) and pore volume (15.35 nm) of m-MCLPICS was obtained from the BET analysis. A pH value of 5 and 0.5 g of adsorbent dose were selected as an optimum values for U(VI) removal. Kinetic data follows the pseudo-second-order model, and the equilibrium data fitted well with the Langmuir isotherm model. ΔG° (-1.6999, -2.4994, -3.5476 and -4.5147 kJ/mol), ΔH0 (25.1 kJ/mol) and ΔS0 (0.089 kJ/mol K) indicates that the U(VI) sorption process is feasible, spontaneous and endothermic.


Asunto(s)
Quitosano/química , Momordica charantia/química , Hojas de la Planta/química , Uranio/química , Contaminantes Radiactivos del Agua/química , Purificación del Agua , Polvos , Aguas Residuales/química
17.
Int J Biol Macromol ; 148: 887-897, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31945442

RESUMEN

In this study m-AHLPICS (magnetic Arachis hypogaea leaves powder impregnated into chitosan) was prepared and utilized as an adsorbent to remove U(VI) from aqueous and real polluted wastewater samples. m-AHLPICS was characterized by using the BET, XRD, FTIR, SEM with elemental mapping and magnetization measurements. Different experimental effects such as pH, dose, contact time, and temperature were considered broadly. Chitosan modified magnetic leaf powder (m-AHLPICS) exhibits an excellent adsorption capacity (232.4 ± 5.59 mg/g) towards U(VI) ions at pH 5. Different kinetic models such as pseudo-first-order, and pseudo-second-order models were used to know the kinetic data. Langmuir, Freundlich and D-R isotherms were implemented to know the adsorption behavior. Isothermal information fitted well with Langmuir isotherm. Kinetic data followed by the pseudo-second-order kinetics (with high R2 values, i.e., 0.9954, 0.9985 and 0.9971) and the thermodynamic data demonstrate that U(VI) removal using m-AHLPICS was feasible, and endothermic in nature.


Asunto(s)
Arachis/química , Quitosano/química , Hojas de la Planta/química , Uranio/química , Contaminantes Radiactivos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Polvos , Análisis Espectral , Temperatura , Termodinámica , Aguas Residuales , Contaminación del Agua , Purificación del Agua
18.
Int J Biol Macromol ; 136: 177-188, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31173826

RESUMEN

It is well-known that heavy metals are non-biodegradable and have been showing remarkable impacts on the environment, public health and economics. Because of high toxic tendency, lead (Pb), is one of the foremost considerable hazardous metal with high environmental impacts. Chitosan is a polysaccharide, and can be utilized in wastewater treatment because of its good sorption ability. Amino and hydroxyl groups (C-3 position) on chitosan can serve as electrostatic interaction and complexation sites for metal cations. Chemical crosslinking can effectively enhance the stability of chitosan in acidic media. Hence a novel, cost-effective and eco-friendly ZnO incorporated into aminated chitosan Schiff's base (ACSSB@ZnO) has been synthesized, characterized (BET, XRD, FTIR, SEM, TEM and 1H NMR), and utilized as an adsorbent for the removal of Pb(II) ions from the aqueous environment. The various operating parameters, such as pH (2-8), agitation speed (30-180), adsorbent dose (0.1-0.8 g), contact time (0-140 min), metal ion concentration and temperature (303-323 K) were investigated. The maximum sorption capacity of Pb(II) onto ACSSB@ZnO was found to be 55.55 mg/g. The equilibrium, and kinetic studies suggested that the adsorption process followed the Langmuir isotherm and Pseudo-Second-Order model. Thermodynamic data showed that the sorption process was feasible, spontaneous, and endothermic.


Asunto(s)
Quitosano/química , Plomo/química , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Bases de Schiff/química , Electricidad Estática , Temperatura , Óxido de Zinc/química
19.
Biomed Res Int ; 2017: 5326962, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28280734

RESUMEN

For out-of-hospital cardiac arrest (OHCA) patients, every second is vital for their life. Shortening the prehospital time is a challenge to emergency medical service (EMS) experts. This study focuses on the on-scene time evaluation of the registered nurses (RNs) participating in already existing EMS teams, in order to explore their role and performance in different EMS cases. In total, 1247 cases were separated into trauma and nontrauma cases. The nontrauma cases were subcategorized into OHCA (NT-O), critical (NT-C), and noncritical (NT-NC) cases, whereas the trauma cases were subcategorized into collar-and-spinal board fixation (T-CS), fracture fixation (T-F), and general trauma (T-G) cases. The average on-scene time of RN-attended cases showed a decrease of 21.05% in NT-O, 3.28% in NT-C, 0% in NT-NC, 18.44% in T-CS, 13.56% in T-F, and 3.46% in T-G compared to non-RN-attended. In NT-O and T-CS cases, the RNs' attendance can notably save the on-scene time with a statistical significance (P = .016 and .017, resp.). Furthermore, the return of spontaneous circulation within two hours (ROSC2 h) rate in the NT-O cases was increased by 12.86%. Based on the findings, the role of RNs in the EMTs could save the golden time in the prehospital medical care in Taiwan.


Asunto(s)
Servicios Médicos de Urgencia , Enfermeras y Enfermeros , Paro Cardíaco Extrahospitalario/terapia , Enfermedad Crítica , Humanos , Curva ROC , Factores de Tiempo , Heridas y Lesiones/complicaciones
20.
Medicine (Baltimore) ; 95(11): e2972, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26986107

RESUMEN

This research focuses on developing an improved and robust measurement for emergency department (ED) performance and a criterion standard for global use via kinetic analysis. Based on kinetic approach, the input-throughput-output conceptual model of ED crowding is compared to the procedure of enzyme catalysis. All in average, the retented patients in EDs are defined as substrate (S), whereas the patients who depart the EDs as product (P). Therefore, the average ED departure velocity (V) can be presented as (P)divided by a given time (t) of the ED length of stay (LOS). The S-V and S²-P plots are depicted hourly for the kinetic analysis. The long-term stability of the kinetic parameters is ascertained by the method of coefficient of variation (CV). The participants collected for this study are from the EDs of Changhua Christian Medical Center and the five branched hospitals, all located in Taiwan. Based on the S-V plot analysis, the results clearly show 2 curves, an upper and a lower curve. The timeline of the lower curve includes approximately the total ED busy hours, and thus it can be used for the subsequent kinetic analysis. In order to explore the adequate kinetic parameters for ED performance, the try-and-error process was followed in this study. As a result, the S²-V plots adapted from the lower curves show the best linear regression of S² on V with a good coefficient of determination (R). The Pan-Wen constant (PW), which is the slope of the liner regression line, and the ED medical personnel unit turnover number (EDMPU TON) were deduced from the kinetic meanings of (Equation is included in full-text article.)plots. In this research, the 2 kinetic parameters, PW and EDMPU TON were applied for the ED performance evaluations. An innovative relationship between the ED retented patients and the ED departure velocity is verified as PW; whereas, a feasible kinetic parameter, the EDMPU TON explicates the teamwork efficiency of the ED providers. Moreover, the EDMPU TON may not only be a reliable universal criterion standard for the ED performance, but also a valuable reference for both ED providers and payers.


Asunto(s)
Eficiencia Organizacional/normas , Servicio de Urgencia en Hospital/organización & administración , Modelos Organizacionales , Admisión del Paciente/normas , Aglomeración , Humanos , Cinética , Tiempo de Internación , Mejoramiento de la Calidad , Taiwán
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