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1.
Digit Discov ; 2(5): 1233-1250, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-38013906

RESUMEN

Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines.

2.
Polymers (Basel) ; 12(6)2020 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-32575714

RESUMEN

In this work, magnetic yeast (MY) was produced through an in situ one-step method. Then, MY was used as the core and the antibiotic sulfamethoxazole (SMX) as the template to produce highly selective magnetic yeast-molecularly imprinted polymers (MY@MIPs). The physicochemical properties of MY@MIPs were assessed by Fourier-transform infrared spectroscopy (FT-IR), a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), specific surface area (SBET) determination, and scanning electron microscopy (SEM). Batch adsorption experiments were carried out to compare MY@MIPs with MY and MY@NIPs (magnetic yeast-molecularly imprinted polymers without template), with MY@MIPs showing a better performance in the removal of SMX from water. Adsorption of SMX onto MY@MIPs was described by the pseudo-second-order kinetic model and the Langmuir isotherm, with maximum adsorption capacities of 77 and 24 mg g-1 from ultrapure and wastewater, respectively. Furthermore, MY@MIPs displayed a highly selective adsorption toward SMX in the presence of other pharmaceuticals, namely diclofenac (DCF) and carbamazepine (CBZ). Finally, regeneration experiments showed that SMX adsorption decreased 21 and 34% after the first and second regeneration cycles, respectively. This work demonstrates that MY@MIPs are promising sorbent materials for the selective removal of SMX from wastewater.

3.
Environ Sci Pollut Res Int ; 27(26): 32603-32614, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32514914

RESUMEN

The coupling of biological and thermal technologies allows for the complete conversion of wastes into energy and biochar eliminating the problem of sludge disposal. The valorisation of fatty residues as co-substrate in a mesophilic digester of a wastewater treatment plant was studied considering an integrated approach of co-digestion and pyrolysis. Four digested samples obtained from co-digestion of sewage sludge and butcher's fat waste were studied by thermogravimetric analysis. The activation energy corresponding to the sludge pyrolysis was calculated by a non-isothermal kinetic. Arrhenius activation energy was lower for the pyrolysis of a digested grease sample (92 kJ mol-1 obtained by OFW and 86 kJ mol-1 obtained by Vyazovkin) than for the pyrolysis of sewage sludge and its blends (164-190 kJ mol-1 obtained by OFW and 162-190 kJ mol-1 obtained by Vyazovkin). The analysis of the integrated approach of anaerobic co-digestion and pyrolysis of digestates demonstrated that the addition of 3% (w/v) of fat to the feeding sludge results in a 25% increase in the electricity obtained from biogas (if a combined heat and power unit is considered for biogas valorisation) and increasing the fat content to 15% allows for covering all thermal needs for drying of digestate and more than doubles (2.4 times) the electricity production when the scenario of digestion and pyrolysis is contemplated.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Anaerobiosis , Biocombustibles/análisis , Reactores Biológicos , Metano , Pirólisis
4.
Environ Sci Pollut Res Int ; 27(29): 36463-36475, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32556991

RESUMEN

Spent brewery grains, a by-product of the brewing process, were used as precursor of biochars and activated carbons to be applied to the removal of pharmaceuticals from water. Biochars were obtained by pyrolysis of the raw materials, while activated carbons were produced by adding a previous chemical activation step. The influence of using different precursors (from distinct fermentation processes), activating agents (potassium hydroxide, sodium hydroxide, and phosphoric acid), pyrolysis temperatures, and residence times was assessed. The adsorbents were physicochemically characterized and applied to the removal of the antiepileptic carbamazepine from water. Potassium hydroxide activation produced the materials with the most promising properties and adsorptive removals, with specific surface areas up to 1120 m2 g-1 and maximum adsorption capacities up to 190 ± 27 mg g-1 in ultrapure water. The adsorption capacity suffered a reduction of < 70% in wastewater, allowing to evaluate the impact of realistic matrices on the efficiency of the materials.


Asunto(s)
Contaminantes Químicos del Agua/análisis , Agua , Adsorción , Carbamazepina/análisis , Carbón Orgánico , Aguas Residuales
5.
Food Chem ; 308: 125633, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31644968

RESUMEN

The objective of this study was to evaluate the in vitro antimicrobial and antioxidant activities of different bran extracts and concentrations, and their influence on the parameters of a mayonnaise-type emulsion. To that end, first ethanol and then water were used to extract two rice bran extracts (RBE) from rice bran. Both these extracts were then added at two different concentrations (0.5 and 2%) to the emulsions that were subsequently analysed after seven days under two different storage temperatures, 4 °C and 20 °C. The antioxidant and antimicrobial ability of the extracts were evaluated, along with a control and a synthetic antioxidant. Results indicate the positive effect of rice bran extracts as additives in the food matrix. Ethanolic rice bran extract (EE) at 2% decreased the oxidation as well as mould and yeast proliferation and preserved the emulsion structure, while the other treatments acted in a similar way although their effect was less pronounced.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Oryza/química , Extractos Vegetales/farmacología , Antibacterianos/química , Antioxidantes/química , Condimentos , Emulsiones , Escherichia coli/efectos de los fármacos , Listeria/efectos de los fármacos , Oxidación-Reducción , Extractos Vegetales/química
6.
Sci Total Environ ; 683: 699-708, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31150890

RESUMEN

This work aimed to assess the fixed-bed adsorptive performance of a primary paper mill sludge-based granular activated carbon (PSA-PA) for the removal of pharmaceuticals, namely carbamazepine (CBZ), sulfamethoxazole (SMX) and paroxetine (PAR), from water. The breakthrough curves corresponding to the adsorption of CBZ at different flow rates and in two different matrices (distilled and municipal wastewater) were firstly determined, which allowed to select the most favorable flow rate for the subsequent experiments. The fixed-bed adsorption of CBZ, SMX and PAR from single and ternary solutions in wastewater showed that the performance of PSA-PA was different for each pharmaceutical. According to the obtained breakthrough curves, the poorest bed adsorption capacity, either from single or ternary solution, was observed for SMX, which may be related with electrostatic repulsion at the pH of the wastewater used (pH ~ 7.3-7.7). Also, the bed adsorption capacity of PSA-PA for SMX, in the ternary solution, was notoriously lower compared to the single solution, while it slightly decreased for CBZ and even increased for PAR. The regeneration studies showed that the CBZ adsorption capacity of the PSA-PA bed decreased about 38 and 71% after the first and the second thermal regeneration stages, respectively. This decline was comparatively larger than the corresponding reduction of the PSA-PA specific surface area (SBET), which decreased only 5 and 25% for the first and second regeneration stages, respectively, and pointed to the lack of viability of more than one regeneration stage.

7.
Environ Sci Pollut Res Int ; 26(22): 22372-22388, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31154640

RESUMEN

The aim of this work is to synthesize a magnetic magnetite/multi-walled carbon nanotube (Fe3O4/MWCNT) catalyst by a method combining co-precipitation and hydrothermal treatments for the efficient removal of diclofenac (DCF) by catalytic wet peroxide oxidation (CWPO). The support (MWCNTs) shows a moderate-large surface area and good adsorption capacity, leading to the improvement of the magnetite (Fe3O4) dispersion on its surface. The response surface methodology (RSM) was applied in order to find out the effect of the reaction parameters on DCF removal, allowing to establish the optimum operating conditions (T = 60 °C, [H2O2]0 = 2.7 mM, [catalyst] = 1.0 g L-1). The optimum CWPO experiment showed an outstanding catalytic activity at non-modified pH solution (6.7), obtaining a 95% of DCF removal after 3 h reaction time; this high efficiency can be attributed to the synergistic effect of the iron-based catalyst with the high quantity of •OH radicals generated on the surface of the catalyst. In addition, the Fe3O4/MWCNT material exhibited good reusability along three consecutive reaction cycles, finding a pollutant removal close to 95% in each cycle of 3 h reaction time. Additionally, a degradation mechanism pathway was proposed for the removal of DCF by CWPO. The versatility of the material was finally demonstrated in the treatment of different environmentally relevant aqueous matrices (a wastewater treatment plant effluent, surface water, and hospital wastewater), obtaining an effective reduction in the ecotoxicity values.


Asunto(s)
Diclofenaco/química , Peróxido de Hidrógeno/química , Hierro/química , Adsorción , Catálisis , Óxido Ferrosoférrico , Nanotubos de Carbono , Oxidación-Reducción , Aguas Residuales , Agua
8.
J Hazard Mater ; 370: 212-218, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29525451

RESUMEN

The wide occurrence of pharmaceuticals in aquatic environments urges the development of cost-effective solutions for their removal from water. In a circular economy context, primary paper mill sludge (PS) was used to produce activated carbon (AC) aiming the adsorptive removal of these contaminants. The use of low-cost precursors for the preparation of ACs capable of competing with commercial ACs continues to be a challenge. A full factorial design of four factors (pyrolysis temperature, residence time, precursor/activating agent ratio, and type of activating agent) at two levels was applied to the production of AC using PS as precursor. The responses analysed were the yield of production, percentage of adsorption for three pharmaceuticals (sulfamethoxazole, carbamazepine, and paroxetine), specific surface area (SBET), and total organic carbon (TOC). Statistical analysis was performed to evaluate influencing factors in the responses and to determine the most favourable production conditions. Four ACs presented very good responses, namely on the adsorption of the pharmaceuticals under study (average adsorption percentage around 78%, which is above that of commercial AC), and SBET between 1389 and 1627 m2 g-1. A desirability analysis pointed out 800 °C for 60 min and a precursor/KOH ratio of 1:1 (w/w) as the optimal production conditions.


Asunto(s)
Carbamazepina/química , Carbón Orgánico/química , Paroxetina/química , Sulfametoxazol/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Adsorción , Residuos Industriales , Papel
9.
Sci Total Environ ; 653: 393-400, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30412884

RESUMEN

In this work, a granular activated carbon (GAC) was produced using primary paper mill sludge (PS) as raw material and ammonium lignosulfonate (AL) as binder agent. PS is a residue from the pulp and paper industry and AL is a by-product of the cellulose pulp manufacture and the proposed production scheme contributes for their valorisation together with important savings in GAC precursors. The produced GAC (named PSA-PA) and a commercially available GAC (GACN), used as reference material, were physically and chemically characterized. Then, these materials were tested in batch experiments for the adsorption of carbamazepine (CBZ), sulfamethoxazole (SMX), and paroxetine (PAR) from ultra-pure water and wastewater. Even though GACN and PSA-PA possess very similar specific surface areas (SBET) (629 and 671 m2 g-1, respectively), PSA-PA displayed lower maximum adsorption capacities (qm) than GACN for the pharmaceuticals here studied (6 ±â€¯1-44 ±â€¯5 mg g-1 and 49 ±â€¯6-106 ±â€¯40 mg g-1, respectively). This may be related to the comparatively higher incidence of mesopores in GACN, which might have positively influenced its adsorptive performance. Moreover, the highest hydrophobic character and degree of aromaticity of GACN could also have contributed to its adsorption capacity. On the other hand, the performance of both GACs was significantly affected by the matrix in the case of CBZ and SMX, with lower qm in wastewater than in ultra-pure water. However, the adsorption of PAR was not affected by the matrix. Electrostatic interactions and pH effects might also have influenced the adsorption of the pharmaceutical compounds in wastewater.


Asunto(s)
Carbón Orgánico/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Compuestos de Amonio/química , Carbamazepina/análisis , Residuos Industriales , Lignina/análogos & derivados , Lignina/química , Paroxetina/análisis , Impresión , Sulfametoxazol/análisis
10.
Food Res Int ; 111: 299-305, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30007689

RESUMEN

The aim of this study has been to assess the composition and antioxidant activities of rice bran extracts submitted to a human simulated digestion, which extraction process was previously optimized. In order to adjust the optimum values for the extraction, D-optimal experimental design and response surface methodology have been applied. Phenolic compounds and γ-oryzanol contents have been used as response parameters. In this way, two different extracts have been obtained. The first one, was obtained with 100% water as solvent, and it was mainly composed by phenolic acids. Ferulic acid was the majority compound found with a concentration of 1.00 ±â€¯0.03 mg/g extract, followed by p-coumaric acid (0.19 ±â€¯0.02 mg/g), The second extract, extracted with ethanol as solvent, was a γ-oryzanol enriched fraction with a content of 14.41 ±â€¯0.26 mg/g extract. The optimized rice bran extracts thus obtained were subjected to a process of human in-vitro digestion. In the first extract, with high polyphenol content, the phenolic content was oscillating during the digestion, like antioxidant activity. The oryzanol content found in this fraction (0.079 ±â€¯0.002 mg/g) has not been detected in any phase of digestion. In the second extract, with a high oryzanol content at the beginning, oryzanol content was not detected in any of digestion steps. However, phenolic composition was stable in all phases of simulation (ranging from 0.117 and 0.094 mg/g in the case of ferulic acid). This fact evidence that oryzanol is not a bioavailability fraction, while phenolic compounds support to some extent, the conditions of digestion.


Asunto(s)
Oryza/química , Oryza/metabolismo , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Antioxidantes/análisis , Antioxidantes/química , Antioxidantes/metabolismo , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Fenilpropionatos/análisis , Fenilpropionatos/química , Fenilpropionatos/metabolismo , Extractos Vegetales/análisis
11.
Bioorg Chem ; 69: 71-76, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27693943

RESUMEN

Michael additions between carbohydrate derived nitroalkenes and several aliphatic and aromatic amines proceeded in a stereoselective way, leading to peracetylated 2-amino-1,2-dideoxy-1-nitro-heptitols. In addition, the antiproliferative activity of some of the new adducts has been studied. The results allowed to identify lead compounds which show GI50 values in the range 1.7-19µM.


Asunto(s)
Antineoplásicos/farmacología , Azúcares Ácidos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Relación Estructura-Actividad , Azúcares Ácidos/síntesis química , Azúcares Ácidos/química
12.
J Colloid Interface Sci ; 448: 32-40, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25710386

RESUMEN

In this work, three adsorbents were produced by using as precursor primary paper mill sludge and applying KOH, NaOH or ZnCl2 as chemical activating agents (PS800-10KOH, PS800-10NaOH and PS800-10ZnCl2) and subjected to pyrolysis. The produced materials were tested for removal of fluoxetine from water, reported as one of the most persistent pharmaceuticals in the aquatic environment. Also, primary sludge pyrolysed under the same conditions but without activation (PS800-10) and a commercial activated carbon (PBFG4) were studied for comparison. Physical and chemical properties of the materials were determined and adsorption kinetic and equilibrium studies were performed in batch experiments. Equilibrium studies allowed testing the capacity of the produced materials for adsorb fluoxetine-HCl, showing no apparent correlation between the S(BET) areas and the adsorption capacities of the materials. The maximum adsorption capacity (mg g(-1)) was of 191.6±4.8 for PS800-10KOH; 136.6±9.6 for PS800-10NaOH; 28.4±0.3 for PS800-10ZnCl2; 120.4±2.5 for PS800-10 and 96.2±1.0 for PBFG4. It was demonstrated that many factors influence the removal of fluoxetine from solution and that the surface area is not the main factor in the process. Also the activation process did not enhance the properties of the produced materials.

13.
Bioresour Technol ; 166: 335-44, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24926607

RESUMEN

This work describes the production of alternative adsorbents from industrial residues and their application for the removal of a highly consumed antidepressant (citalopram) from water. The adsorbents were produced by pyrolysis of both primary and biological paper mill sludge at different temperatures and residence times. The original sludge and the produced chars were fully characterized by elemental and proximate analyses, total organic carbon, specific surface area (BET), N2 isotherms, FTIR, (13)C and (1)H solid state NMR and SEM. Batch kinetic and equilibrium experiments were carried out to describe the adsorption of citalopram onto the produced materials. The fastest kinetics and the highest adsorption capacity were obtained using primary sludge pyrolysed at 800 °C during 150 min. The use of pyrolysed paper mill sludge for the remediation of contaminated waters might constitute an interesting application for the valorization of those wastes.


Asunto(s)
Carbono/química , Citalopram/análisis , Papel , Aguas del Alcantarillado/química , Purificación del Agua/métodos , Adsorción , Citalopram/química , Eucalyptus , Cinética
14.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 28(supl.4): 28-31, nov. 2010. tab
Artículo en Español | IBECS | ID: ibc-179587

RESUMEN

En el hospital, y dentro de él en las unidades de cuidados intensivos, se concentra la mayor densidad de consumo de antimicrobianos. La calidad del uso de antimicrobianos no es óptima, hasta el 50% de las prescripciones son innecesarias o inapropiadas. Las consecuencias del uso inapropiado son muy graves, incrementa la mortalidad y la morbilidad de los pacientes, y las resistencias microbianas. Y la razón fundamental del uso inapropiado es el conocimiento insuficiente de la cada vez más ingente y compleja información acerca del diagnóstico y el tratamiento de las enfermedades infecciosas. Hay acuerdo general en la necesidad de mejorar el uso de antimicrobianos en los hospitales, pero no en cómo hacerlo. El Hospital Universitario Virgen del Rocío (Sevilla) ha puesto en marcha el Programa Institucional para la Optimización del Tratamiento Antimicrobiano (PRIOAM), inspirado en las recomendaciones de la Sociedad Americana de Enfermedades Infecciosas, y adaptado a las características estructurales, funcionales y culturales del Hospital. El PRIOAM está coordinado por un equipo multidisciplinar elegido por la Comisión de Infecciones y Antimicrobianos y tiene 3 características básicas: es un programa institucional y con incentivos ligados a la consecución de objetivos; es un programa educativo, porque la formación y el conocimiento son la base para el buen uso de los antimicrobianos, y es un programa sujeto a resultados, en el que el objetivo principal es clínico, no económico, reducir la mortalidad y la morbilidad de los pacientes con infecciones y retrasar el desarrollo de resistencias


The largest consumption of antimicrobials is concentrated in hospitals and within them, the intensive care units. The quality of antimicrobial use is not optimal, with up to 50% of prescriptions being unnecessary or inappropriate. Inappropiate antibiotic use leads to severe consequences, such as increased patient mortality and morbidity and bacterial resistance. The primary reason for inappropriate use is the insufficient knowledge of the increasingly vast and complex information about the diagnosis and treatment of infectious diseases. There is general agreement on the need to improve the use of antimicrobials in hospitals but not on how to improve it. University Hospital Virgen del Rocío (Seville) has launched the Institutional Programme for the Optimisation of Antimicrobial Treatment (PRIOAM), inspired by the recommendations of the Infectious Diseases Society of America and adapted to the structural, functional and cultural characteristics of the hospital. PRIOAM is coordinated by a multidisciplinary team chosen by the Committee on Infections and Antimicrobials and has three basic characteristics: it is an institutional programme that has incentives linked to achieving goals; it is an educational programme in which training and knowledge are the basis for the proper use of antimicrobials; and it is a programme subject to results, in which the main objectives are clinical, not economic, to reduce mortality and morbidity in patients with infections and to delay the development of resistance


Asunto(s)
Humanos , Antibacterianos/uso terapéutico , Hospitales , Farmacorresistencia Bacteriana , Utilización de Medicamentos/estadística & datos numéricos , Utilización de Medicamentos/normas
15.
Enferm Infecc Microbiol Clin ; 28 Suppl 4: 28-31, 2010 Nov.
Artículo en Español | MEDLINE | ID: mdl-21458697

RESUMEN

The largest consumption of antimicrobials is concentrated in hospitals and within them, the intensive care units. The quality of antimicrobial use is not optimal, with up to 50% of prescriptions being unnecessary or inappropriate. Inappropriate antibiotic use leads to severe consequences, such as increased patient mortality and morbidity and bacterial resistance. The primary reason for inappropriate use is the insufficient knowledge of the increasingly vast and complex information about the diagnosis and treatment of infectious diseases. There is general agreement on the need to improve the use of antimicrobials in hospitals but not on how to improve it. University Hospital Virgen del Rocío (Seville) has launched the Institutional Programme for the Optimisation of Antimicrobial Treatment (PRIOAM), inspired by the recommendations of the Infectious Diseases Society of America and adapted to the structural, functional and cultural characteristics of the hospital. PRIOAM is coordinated by a multidisciplinary team chosen by the Committee on Infections and Antimicrobials and has three basic characteristics: it is an institutional programme that has incentives linked to achieving goals; it is an educational programme in which training and knowledge are the basis for the proper use of antimicrobials; and it is a programme subject to results, in which the main objectives are clinical, not economic, to reduce mortality and morbidity in patients with infections and to delay the development of resistance.


Asunto(s)
Antibacterianos/uso terapéutico , Hospitales , Farmacorresistencia Bacteriana , Utilización de Medicamentos/normas , Utilización de Medicamentos/estadística & datos numéricos , Humanos , Guías de Práctica Clínica como Asunto
16.
Bioresour Technol ; 99(13): 5763-72, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18036814

RESUMEN

Multivariate analysis was used for interpreting data from a pot experiment using samples of three Spanish soils. Samples of soil fertilized with compost were compared with untreated control samples. We also compared the effect of adding the compost to soil with a controlled moisture content of 50% of its water holding capacity (WHC), and to a near-saturated soil (95% WHC). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used; they perfectly differentiated sample groups both as a function of the treatment applied and by sampling date. The compost samples were characterized by higher pH, electrical conductivity (EC), organic matter (OM) content and cation exchange capacity (CEC), together with nutrient concentrations than the control pots. The pots with a soil-compost mixture at 95% WHC presented lower values of EC, CEC, inorganic N, K, Na and B than the mixtures at 50% WHC. Multivariate methods may therefore be useful for the analysis and interpretation of a large number of data in soil research.


Asunto(s)
Agricultura/métodos , Estiércol , Suelo/normas , Animales , Bovinos , Análisis por Conglomerados , Monitoreo del Ambiente/métodos , Análisis Multivariante , Suelo/análisis , España
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