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1.
Environ Geochem Health ; 43(7): 2539-2550, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32394057

RESUMEN

The removal of methyl orange using coal fly ash, which is a widely available low-cost adsorbent, has been investigated. Adsorption studies for dye removal were conducted using various configurations such as batch, column and heap adsorption at various temperatures and adsorbent dosages at neutral pH. The Langmuir, Freundlich and Tempkin isotherm models were used to describe the process. The Freundlich model best represented the adsorption. Kinetic studies show the adsorption followed pseudo-second-order kinetics. Thermodynamic studies show that the process is spontaneous, endothermic and random. Column configuration was found to be the most efficient with a dye removal percentage of 99.95%, followed by heap adsorption at 99.25% removal and lastly batch configuration with 96.68% removal. Economic analysis shows that column operation would be the most effective for practical implementation.


Asunto(s)
Compuestos Azo/química , Ceniza del Carbón/química , Termodinámica , Aguas Residuales/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
2.
Data Brief ; 21: 1458-1471, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30456271

RESUMEN

The data presented in this paper are related to the research article entitled "Synthesis, characterisation and electrochemistry of eight Fe coordination compounds containing substituted 2-(1-(4-R-phenyl-1H-1,2,3-triazol-4-yl)pyridine ligands, R=CH3, OCH3, COOH, F, Cl, CN, H and CF3." (Conradie et al., 2019) [1]. This paper presents electrochemical and density functional theory data of 4-phenyl-substituted dichloro(bis{2-[1-(4-R-phenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})iron(II) compounds, containing differently substituted 2-(1-(4-R-phenyl)-1H-1,2,3-triazol-1-yl)pyridine ligands (L2 - L9) (Tawfiq et al., 2014) [2]. Density functional theory calculated data of five different structural isomers for each compound, consistently show that the title compounds are octahedral and that the isomer with the chloride atoms, the pyridine nitrogens and the triazol nitrogens trans to each other, has the lowest energy. Natural bonding orbital (NBO) data and quantum theory of atoms in molecules (QTAIM) data of dichloro(bis{2-[1-(phenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})iron(II) show origin for the preference of the trans isomer.

3.
Data Brief ; 20: 1397-1408, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30255118

RESUMEN

The data presented in this paper are related to the research article entitled "Novel dichloro(bis{2-[1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})metal(II) coordination compounds of seven transition metals (Mn, Fe, Co, Ni, Cu, Zn and Cd)" (Conradie et al., 2018) [1]. This paper presents characterization and structural data of the 2-(1-(4-methyl-phenyl)-1H-1,2,3-triazol-1-yl)pyridine ligand (L2) (Tawfiq et al., 2014) [2] as well as seven dichloro(bis{2-[1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})metal(II) coordination compounds, [M(L2)2Cl2], all containing the same ligand but coordinated to different metal ions. The data illustrate the shift in IR, UV/VIS, and NMR (for diamagnetic complexes) peaks when L is coordinated to the metals, as well as the influence of the different metals on the peak positions. Solid state structural data is presented for M = Ni and Zn, while density functional theory calculated energies, structures and optimized coordinates are provided for the lowest energy cis and trans conformations for L2 as well as [M(L2)2Cl2] with M = Mn, Fe, Co, Ni, Cu, Zn and Cd.

4.
Environ Technol ; 33(10-12): 1191-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22856289

RESUMEN

The rate of the dissolution of quicklime was measured in different organic solvents and solutions of methanol, ethylene glycol, glycerol and sucrose. It was found that the rate of dissolution in methanol, glycerol and sucrose was dramatically reduced compared with that in deionized water. However, little difference was measured in a solution of ethylene glycol compared with aqueous solutions. The presence of chloride ions increases the rate of dissolution in all solvents and solutions, except for ethylene glycol, where a decrease was actually observed. It was also found that the presence of sulphate ions decreases the rate in all organic solvents and solutions tested.


Asunto(s)
Compuestos de Calcio/química , Compuestos Orgánicos/química , Óxidos/química , Solventes/química , Glicol de Etileno/química , Estudios de Factibilidad , Glicerol/química , Cinética , Metanol/química , Sacarosa/química
5.
Int J Clin Pharmacol Ther ; 46(3): 119-30, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18397682

RESUMEN

OBJECTIVE: Antiepileptic drugs are often used in patients with some degree of renal impairment. The objective of this study was to evaluate the effect of renal function on the pharmacokinetics of eslicarbazepine acetate (ESL, formerly known as BIA 2-093), a new antiepileptic drug under clinical development. METHODS: ESL pharmacokinetics following 800 mg single dose was characterized in subjects with normal renal function (n=8, control group), and in patients with mild renal impairment (n=8), moderate renal impairment (n=8), severe renal impairment (n=8), and end-stage renal disease requiring hemodialysis (n=8). RESULTS: ESL suffered extensive first-pass hydrolysis to eslicarbazepine (S-licarbazepine), the main active metabolite. While eslicarbazepine Cmax did not significantly differ between the different groups, the extent of systemic exposure, assessed by AUC, increased when renal function decreased. Eslicarbazepine CL/F and CLR were, respectively, 3.40 l/h and 1.04 l/h (17.3 ml/min) in the control group, and 2.10 l/h (35.0 ml/min) and 0.61 l/h (10.2 ml/min) in the mild, 1.60 l/h (26.7 ml/min) and 0.22 l/h (3.7 ml/min) in the moderate, and 1.33 l/h (21.2 ml/min) and 0.09 l/h (1.5 ml/min) in the severe renal impairment groups. Although the total amount of eslicarbazepine recovered in urine until 72 h post-dose was similar in the control and mild renal impairment groups, a decrease was found in the moderate and severe renal impairment groups. Major metabolites recovered in urine were eslicarbazepine and its glucuronide form. Clearance of minor metabolites (R-licarbazepine, oxcarbazepine and their glucuronides) was also dependent on renal function. In patients with end-stage renal disease, dialysis was effective in removing the ESL metabolites from the circulation. CONCLUSIONS: ESL metabolites are excreted primarily by renal route and their clearance is dependent on renal function. ESL dosage adjustment may be necessary in patients with a creatinine clearance <60 ml/min.


Asunto(s)
Anticonvulsivantes/farmacocinética , Dibenzazepinas/farmacocinética , Insuficiencia Renal/metabolismo , Adulto , Anciano , Anticonvulsivantes/sangre , Anticonvulsivantes/orina , Área Bajo la Curva , Dibenzazepinas/sangre , Dibenzazepinas/orina , Femenino , Semivida , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad
6.
Mar Pollut Bull ; 52(6): 606-11, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16772114

RESUMEN

This contribution describes the distribution of marine salt aerosols in Belgium, France and Spain, as obtained from applying a kriging model to a set of data. The data was collected over a period of nine years and included wet as well as dry deposition results. It was found that the concentration of the salt particles decreased the fastest in Spain and the slowest in Belgium with increasing inland distance from the sea. These findings have implications for the degradation of monuments and historical buildings as a result of salt attack and ingress that often accompany degradation due to air pollution.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Cloruro de Sodio/análisis , Aerosoles , Movimientos del Aire , Atmósfera/análisis , Atmósfera/química , Bélgica , Francia , Cloruro de Sodio/efectos adversos , España
7.
Exp Clin Endocrinol Diabetes ; 113(8): 435-43, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16151977

RESUMEN

AIMS/HYPOTHESIS: This study compared the pharmacokinetics and pharmacodynamics of insulin glulisine, insulin lispro, and regular human insulin in obese subjects. METHODS: In this single-dose, randomized, double-blind, crossover euglycaemic clamp study, 18 non-diabetic subjects (mean body mass index [BMI] 34.7 kg . m (-2)) were randomized to receive subcutaneous injections of each insulin (0.3 U . kg (-1)) in pre-determined sequences. RESULTS: Insulin glulisine and insulin lispro had more rapid-acting profiles than regular human insulin. Fractional glucose infusion rate (GIR)-area under curves (AUC) of the GIR curve and maximum GIR were greater for insulin glulisine and insulin lispro versus regular human insulin. Total glucose disposal was slightly greater with insulin glulisine than with regular human insulin, and was comparable to insulin lispro, although it decreased with increasing insulin resistance (HOMA index) with all insulins. Time to 20 % (early glucose disposal) and 80 % (bulk of activity) of total GIR-AUC were shorter for insulin glulisine and insulin lispro versus regular human insulin. This was corroborated by more rapid and shorter residing pharmacokinetic profiles of insulin glulisine and insulin lispro versus regular human insulin, evidenced by shorter times to 20 % of total INS-AUC, INS-C (max) (INS-t (max)), and mean residence time. Moreover, time to 20 % of total GIR-AUC demonstrated a less rapid-acting profile for insulin lispro versus insulin glulisine, which was consistent with the slightly less rapid pharmacokinetic profile of insulin lispro. There was no significant correlation between BMI or subcutaneous fat thickness and pharmacokinetic or pharmacodynamic profiles for insulin glulisine, unlike insulin lispro and regular human insulin. CONCLUSIONS/INTERPRETATION: Insulin glulisine and insulin lispro demonstrated substantially more rapid time-action profiles than regular human insulin in obese non-diabetic subjects, which prevailed with insulin glulisine irrespective of BMI and subcutaneous fat thickness.


Asunto(s)
Hipoglucemiantes/farmacocinética , Insulina/análogos & derivados , Obesidad , Adulto , Glucemia/efectos de los fármacos , Método Doble Ciego , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Inyecciones Subcutáneas , Insulina/administración & dosificación , Insulina/farmacocinética , Insulina Lispro , Masculino , Persona de Mediana Edad , Obesidad/sangre , Tiempo
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(11-12): 2460-7, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16043039

RESUMEN

Research concerning the formation and removal of black crusts on various historical objects is approached from many different angles. The so-called "yellowing effect", observed after laser treatment for cleaning purposes, has also received a lot of attention. Evidence regarding this phenomenon differs considerably and the actual mechanisms are still speculated on by researchers. In an attempt to elucidate the processes involved in the yellowing effect associated with laser cleaning, a new analytical technique has been used to investigate the black crust, a region of the sample cleaned by laser irradiation at 1064 nm and another region of the same sample subjected to further laser irradiation at 355 nm, on a limestone sample from the cathedral of Seville in Spain. Micro-Raman spectrometry offers the advantage of spatial chemical characterization of the stone, based upon its molecular makeup and was performed on the bulk body of the stone. Raman and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDXS) results indicate that the surfaces cleaned by irradiation at 1064 nm and by double irradiation at 1064 and 355 nm differed in terms of their calcium sulphate, calcium oxalate and iron oxide content, and that this could contribute to the difference in colour observed.


Asunto(s)
Carbonato de Calcio/química , Color , Rayos Láser , Materiales de Construcción/análisis , Microscopía Electrónica de Rastreo , España , Espectrometría por Rayos X , Espectrometría Raman
9.
Exp Clin Endocrinol Diabetes ; 113(5): 292-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15926116

RESUMEN

Insulin glulisine is a new rapid-acting insulin analog. The aim of this study was to assess the glucodynamic efficacy of insulin glulisine compared with regular human insulin (RHI) using a manual euglycemic clamp technique. Steady-state pharmacokinetics of insulin glulisine, and its cardiac safety (ECG) and tolerability after intravenous administration, were also determined. This was a single center, randomized, open-label, two-way crossover study in healthy male subjects (n = 16). At the treatment visits subjects received an intravenous infusion of the study drug at a rate of 0.8 mU kg (-1) . min (-1) for 2 hours. Individual baseline glucose concentrations were targeted for euglycaemia and maintained with a manual adjusted 20 % glucose solution over the clamp period of a maximum 6 hours. A glulisine-specific antibody was used to quantify glulisine concentrations by radioimmunoassay, while a non-specific insulin antibody and C-peptide based correction for endogenous insulin was used to estimate exogenous human insulin (RHI). At steady state (90 - 120 min), insulin glulisine and RHI had equivalent glucose utilization (GIR-AUC (SS), 209 [corrected] mg . kg (-1) for glulisine, 214 [corrected] mg . kg (-1) for RHI) and infusion rates (GIR (SS), 7.0 and 7.2 [corrected] mg . kg (-1) . [corrected] min (-1) . kg (-1)). Both insulins also presented equal total glucose disposal (GIR-AUC (0 - clamp end), 995 and 1050 [corrected] mg . kg (-1)) and onset of activity within 20 min. Insulin glulisine and RHI showed parallel time concentration profiles with similar distribution and elimination, but the different antibodies employed for radioimmunoassay impeded a quantitative comparison. There were no noteworthy individual or within-group changes in cardiac repolarisation parameters measured by 12-lead ECG during insulin glulisine infusion. In conclusion, insulin glulisine and RHI show similar distribution and elimination profiles and equivalent glucodynamic efficacy on a molar, unit-per-unit basis.


Asunto(s)
Técnica de Clampeo de la Glucosa , Insulina/análogos & derivados , Insulina/farmacología , Insulina/farmacocinética , Adulto , Glucemia/análisis , Estudios Cruzados , Humanos , Cinética , Masculino , Proteínas Recombinantes
10.
S Afr Med J ; 89(11): 1182-8, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10599300

RESUMEN

OBJECTIVE: To evaluate a recently developed low-dose, large-field, direct digital X-ray scanning system for medical use. METHOD: Radiation dose, image quality, diagnostic capability and clinical utility of the unit were compared with those of conventional radiography. RESULTS: Radiation doses ranged from 3% to 5% of conventional radiographic values, and a mean of 1 line-pair per millimetre could be detected. Ease of use, anatomical coverage and tolerance to patient motion were advantages. However, image quality was inferior to that of conventional radiographs, with limited fine detail visibility and penetration. Only 67 of 156 (42.9%) pathological features seen on conventional radiographs were detected, including 13 of 41 fractures (31.7%) and 11 of 18 pneumothoraces (61.1%). CONCLUSION: Although image quality and diagnostic performance were not ideal, potential roles in triage, foreign body detection and possibly screening were promising. Radiographic factors may have affected sensitivity. This machine demonstrated useful attributes that may, with improvement, be beneficial in the imaging of trauma and other patients.


Asunto(s)
Intensificación de Imagen Radiográfica/instrumentación , Adolescente , Adulto , Anciano , Niño , Preescolar , Diseño de Equipo/normas , Estudios de Evaluación como Asunto , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Dosis de Radiación , Intensificación de Imagen Radiográfica/normas , Radiografía Abdominal/métodos , Radiografía Abdominal/normas , Radiografía Torácica/métodos , Radiografía Torácica/normas , Heridas por Arma de Fuego/diagnóstico por imagen , Heridas Punzantes/diagnóstico por imagen
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