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1.
Int J Biol Macromol ; 273(Pt 1): 133015, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38857731

RESUMEN

Cosmetics, textiles, foodstuffs, and medicines frequently contain the yellow dye tartrazine. It has carcinogenic properties and can trigger allergies. In this study, a unique NH2-MIL-101(Cr)/chitosan composite (MIL/chitosan composite) was created using a hydrothermal process. The effectiveness of this composite in removing Tartrazine (TZ) from aqueous solutions was investigated. It was characterized via FT-IR, XPS, XRD, and BET analysis. The surface area of the MIL/chitosan nanoadsorbent sample was 1256.64 m2/g, where after five times recycling, it was reduced to 1068.14 m2/g. The study analyzed the impact of dye concentration, pH, temperature, and MIL/chitosan composite dosage. Experimental measurements were taken for the equilibrium isotherms of dye adsorption. The kinetic models and adsorption isotherm were used to analyze the results. The adsorption process was found to match Langmuir and pseudo-second-order kinetic models. Chemisorption was the mechanism of the adsorption process. Based on thermodynamic parameters, it was determined that the adsorption process was endothermic. The MIL/chitosan composite was recycled up to five cycles. Using the MIL/chitosan composite towards the adsorption of the tartrazine from the real sample has been checked. The interaction process between the MIL/chitosan nanoadsorbent and Tartrazine adsorbate has been investigated. The TZ electrical characteristics, reactivity, and shape were ascertained through the application of density functional theory (DFT). The placement of electrophilic and nucleophilic attack sites is in good agreement with the molecular orbitals (HOMO and LUMO) and MEP results, according to DFT. The optimization of adsorption results was accomplished using Box-Behnken design (BBD).


Asunto(s)
Quitosano , Estructuras Metalorgánicas , Tartrazina , Contaminantes Químicos del Agua , Quitosano/química , Tartrazina/química , Estructuras Metalorgánicas/química , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Concentración de Iones de Hidrógeno , Purificación del Agua/métodos , Temperatura , Termodinámica , Colorantes/química , Colorantes/aislamiento & purificación , Agua/química , Soluciones
2.
Environ Res ; 205: 112543, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34915029

RESUMEN

The present research concerns the synthesis of a mesoporous composite characterized with high surface area and superior adsorption capacity in order to investigate its efficacity in removing hazardous and harmful dyes molecules from water. The synthesized mesoporous composite, MgO/g-C3N4 (MGCN), was successfully prepared through the sonication method in a methanolic solution followed by an evaporation and a calcination process. The configuration, crystalline phase, surface properties, chemical bonding, and morphological study of the fabricated nanomaterials were investigated via XRD, BET, FESEM, HRTEM, XPS, and FTIR instrumentation. The obtained nanomaterials were used as sorbents of Congo Red (CR) and Basic Fuchsin (BF) dyes from aqueous solutions. Batch elimination experimental studies reveal that the elimination of CR and BF dyes from an aqueous solution onto the MGCN surface was pH-dependent. The highest removal of CR and BF pollutants occurs, respectively, at pH 5 and 7. The absorptive elimination of CR and BF dyes into the MGCN surface was well-fitted with a pseudo-second-order kinetics and Langmuir model. In this concern, the maximum nanocomposite elimination capacity for CR and BF was observed to be 1250 and 1791 mg g-1, respectively. This investigation confirms that MGCN composite is an obvious and efficient adsorbent of CR, BF, and other organic dyes from wastewater.


Asunto(s)
Colorantes , Contaminantes Químicos del Agua , Adsorción , Colorantes/química , Concentración de Iones de Hidrógeno , Cinética , Óxido de Magnesio , Contaminantes Químicos del Agua/análisis
3.
Ann Cardiol Angeiol (Paris) ; 64(6): 439-45, 2015 Dec.
Artículo en Francés | MEDLINE | ID: mdl-26547525

RESUMEN

UNLABELLED: FAST-MI Tunisian registry was initiated by the Tunisian Society of Cardiology and Cardio-vascular Surgery to assess characteristics, management, and hospital outcomes in patients with ST-elevation myocardial infarction (STEMI). METHODS: We prospectively collected data from 203 consecutive patients (mean age 60.3 years, 79.8 % male) with STEMI who were treated in 15 public hospitals (representing 68.2 % of Tunisian public centres treating STEMI patients) during a 3-month period at the end of 2014. The most common risk factor was tobacco (64.9 %), hypertension (38.6 %), diabetes (36.9 %) and dyslipidemia (24.6 %). RESULTS: Among these patients, 66 % received reperfusion therapy, 35 % with primary percutaneous coronary interventions (PAMI), 31 % with thrombolysis (28.6 % of them by pre-hospital thrombolysis). The median time from symptom onset to thrombolysis was 185 and 358 min for PAMI, respectively. The in-hospital mortality was 7.0 %. Patients enrolled in interventional centers (n=156) were more likely to receive any reperfusion therapy (19.8 % vs 44.6 %; p<0.001) than at the regional system of care with less thrombolysis (26.9 % vs 44.6 %; p=0.008) and more PAMI (52.8 % vs 8.5 %; p<0.0001). Also the in-hospital mortality was lower (6.4 % vs 9.3 %) but not significant. CONCLUSIONS: Preliminary results from FAST-MI in Tunisia show that the pharmaco- invasive strategy should be promoted in non-interventional centers.


Asunto(s)
Angioplastia , Antiinflamatorios no Esteroideos/uso terapéutico , Anticoagulantes/uso terapéutico , Cardiología , Heparina/uso terapéutico , Infarto del Miocardio/terapia , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia/métodos , Angioplastia/estadística & datos numéricos , Quimioterapia Combinada , Femenino , Hospitales Públicos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Estudios Prospectivos , Sistema de Registros , Factores de Riesgo , Sociedades Médicas , Resultado del Tratamiento , Túnez/epidemiología
4.
Ultrason Sonochem ; 20(1): 571-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22677454

RESUMEN

Cationization of cotton fabric was conferred by the sonicator reaction of cellulose with bromoacetyl bromide, followed by substitution of the terminal bromo groups by triethylamine. Experiments showed that the optimal volume of bromoacetyl bromide necessary to succeed the first stage was 0.4 mL. The order of weight gain for various processes indicates, ultrasound, 25 kHz> ultrasound, 40 kHz> mechanical stirring. Also, for the second stage the order of nitrogen contents indicates ultrasound, 25 kHz> ultrasound, 40 kHz> mechanical stirring. The structures of both untreated and cationic fibres were investigated by FTIR spectroscopy. Modified cotton fabric was subsequently dyed in both conventional and ultrasonic techniques with isosalipurposide dye isolated from Acacia cyanophylla yellow flowers. The effect of dye bath pH, ultrasonic power and frequency, dyeing time and temperature were studied and the order of K/S values indicates ultrasound, 25 kHz > ultrasound, 40 kHz > CH. ultrasound was also found to enhance the dye uptake and the overall fastness properties. Analysis of the sorption isotherms of isosalipurposide dye on cationic cotton fabric shows that the Languimir isotherm equation is best able to correlate the data.


Asunto(s)
Colorantes/química , Fibra de Algodón , Sonicación/métodos , Acilación , Etilaminas/química
5.
Acta Crystallogr C ; 56 (Pt 5): 511-2, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10851596
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