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1.
Ecotoxicol Environ Saf ; 162: 245-252, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29990737

RESUMO

Click chemistry refers to a group of reactions that are fast, simple to use, easy to purify, versatile, regiospecific, and give high product yields. Therefore, a novel, efficient magnetic nano-sorbent based on N-methyl-D-glucamine attached to magnetic nanoparticles was prepared using click coupling method. Its boron sorption capacity was compared with N-methyl-D-glucamine direct attached nano-sorbent. The characterization of the magnetic sorbents was investigated by several techniques such as X-ray diffraction, scanning electron microscope, transmission electron microscope, dynamic light scattering, thermogravimetric analysis, Fourier transform infrared spectrophotometer, and vibrating sample magnetometer. The boron sorption capacity of sorbents was compared by studying various essential factors influencing the sorption, like sorbate concentration, sorbents dosage, pH of the solution, and contact time. Langmuir and Freundlich and Dubinin-Radushkevich adsorption isotherms models were applied. Percent removal and sorption capacities efficiencies of sorbents obtained with direct and click coupling are found to be 49.5%, 98.7% and 6.68 mg/g, 13.44 mg/g respectively. Both sorbents have been found to be compatible with Langmuir isotherm, and the boron sorption kinetics conforms to the pseudo second order kinetics. The reusability study of sorbents was carried out five times for boron sorption and desorption.


Assuntos
Boro/química , Química Click , Meglumina/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Boro/análise , Concentração de Íons de Hidrogênio , Cinética , Magnetismo , Dióxido de Silício/química , Poluentes Químicos da Água/análise
2.
J Sep Sci ; 37(22): 3370-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25199632

RESUMO

The isolation of ß-nicotinamide adenine dinucleotide is of great importance since it is widely used in different scientific and technologic fields such as biofuel cells, sensor technology, and hydrogen production. In order to isolate ß-nicotinamide adenine dinucleotide, first 3-aminophenyboronic acid functionalized magnetic nanoparticles were prepared to serve as a magnetic solid support and subsequently they were used for reversible adsorption/desorption of ß-nicotinamide adenine dinucleotide in a batch fashion. The loading capacity of the 3-aminophenyboronic acid functionalized nanoparticles for ß-nicotinamide adenine dinucleotide adsorption was 13.0 µmol/g. Adsorption kinetic and isotherm studies showed that the adsorption process followed a pseudo-second-order kinetic model and the experimental data can be represented using Langmuir isotherm model. The 3-aminophenyboronic acid functionalized magnetic nanoparticles were proposed as an alternative support for the ß-nicotinamide adenine dinucleotide purification. The results elucidated the significance of magnetic separation as a fast, relatively simple, and low-cost technique. Furthermore, the magnetic supports can be reused at least five times for purification processes.


Assuntos
Ácidos Borônicos/química , Hidrogênio/química , NAD/química , Nanopartículas/química , Nanotecnologia/métodos , Adsorção , Biocombustíveis , Concentração de Íons de Hidrogênio , Cinética , Ligantes , Magnetismo , Transição de Fase , Reprodutibilidade dos Testes , Siloxanas/química
3.
Auris Nasus Larynx ; 51(3): 437-442, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520974

RESUMO

OBJECTIVE(S): Our aim is to investigate the effects of the submucoperichondrial application of Platelet Rich Plasma (PRP) on nasal mucosal healing after septoplasty surgery. METHOD(S): This prospective randomized observational study was conducted between July 2019 and February 2021, with 40 patients aged 18-60 years who underwent closed the only septoplasty operation for similar septal deviations. Patient divided into two group; 21 patients were placed in PRP group to which PRP was applied on all mucosal surface and submucoperichondrial area of septum and 19 patients were placed in control group to which saline solution was applied on same regions. Nasal obstruction score, mucociliary clearance time, presence of nasal crusting, and bleeding time were evaluated on 5th, 10th, 15th day after surgery and compared between groups. RESULTS: Intranasal crusting on day 10 was found to be lower in the PRP group (n:13 68.4 %) than control group (n:7 33.3 %) with a statistically significant difference (p = 0.028). The nasal obstruction score on day 10 and 15 were found to be lower in the PRP group (3,33 ± 2,75, 2,07 ± 2,20) (than the control group (5,44 ± 2,26, 3,37 ± 1,92) with a statistically significant difference (p = 0,003,p = 0,009). The mucociliary clearance rate was found to be higher and the bleeding time was found to be lower in the PRP group, but a statistically significant difference was not observed. CONCLUSIONS: Application of submucoperichondrial PRP could have beneficial effects on nasal mucosal repair, nasal crusting, and congestion after septoplasty surgery.


Assuntos
Mucosa Nasal , Septo Nasal , Plasma Rico em Plaquetas , Rinoplastia , Cicatrização , Humanos , Adulto , Septo Nasal/cirurgia , Feminino , Masculino , Pessoa de Meia-Idade , Rinoplastia/métodos , Estudos Prospectivos , Adulto Jovem , Adolescente , Depuração Mucociliar , Obstrução Nasal/cirurgia
4.
Environ Sci Pollut Res Int ; 28(5): 5231-5253, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32964387

RESUMO

The present study, for the first time, utilized 3,4-diaminobenzophenone (DABP)-functionalized Fe3O4/AC@SiO2 (Fe3O4/AC@SiO2@DABP) magnetic nanoparticles (MNPs) synthesized as a nanoadsorbent for enhancing adsorption and desorption capacity of gaseous benzene and toluene as volatile organic compounds (VOCs). The Fe3O4/AC@SiO2@DABP MNPs used in adsorption and desorption of benzene and toluene were synthesized by the co-precipitation and sol-gel methods. The synthesized MNPs were characterized by SEM, FTIR, TGA/DTA, and BET surface area analysis. Moreover, the optimization of the process parameters, namely contact time, initial VOC concentration, and temperature, was performed by applying response surface methodology (RSM). Adsorption results demonstrated that the Fe3O4/AC@SiO2@DABP MNPs had excellent adsorption capacity. The maximum adsorption capacities for benzene and toluene were found as 530.99 and 666.00 mg/g, respectively, under optimum process parameters (contact time 55.47 min, initial benzene concentration 17.57 ppm, and temperature 29.09 °C; and contact time 57.54 min, initial toluene concentration 17.83 ppm, and temperature 27.93 °C for benzene and toluene, respectively). In addition to the distinctive adsorptive behavior, the Fe3O4/AC@SiO2@DABP MNPs exhibited a high reproducibility adsorption and desorption capacity. After the fifth adsorption and desorption cycles, the Fe3O4/AC@SiO2@DABP MNPs retained 94.4% and 95.4% of its initial adsorption capacity for benzene and toluene, respectively. Kinetic and isotherm findings suggested that the adsorption mechanisms of benzene and toluene on the Fe3O4/AC@SiO2@DABP MNPs were physical processes. The results indicated that the successfully synthesized Fe3O4/AC@SiO2@DABP MNPs can be applied as an attractive, highly effective, reusable, and cost-effective adsorbent for the adsorption of VOC pollutants.Graphical abstract.


Assuntos
Compostos Orgânicos Voláteis , Adsorção , Benzofenonas , Fenômenos Magnéticos , Fenilenodiaminas , Reprodutibilidade dos Testes , Dióxido de Silício
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