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1.
Ecotoxicol Environ Saf ; 254: 114698, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36871352

RESUMO

In this study, we synthesized and employed the amine impregnated activated carbon as an efficacious adsorbent for uptaking gasoline vapor. For this regard, anthracite as activated carbon source and hexamethylenetetramine (HMTA) as amine were selected and utilized. Physiochemical characterization of made sorbents were evaluated and investigated using SEM, FESEM, BET, FTIR, XRD, zeta potential, and elemental analysis. The synthesized sorbents provided an excellent textural features as compared with the literature and other activated carbon based sorbents and impregnated with amine. Our findings also suggested that in addition to high surface area (up to 2150 m2 / g), the micro- meso pores created (Vmeso / V micro = 0.79 Cm 3 / g) surface chemistry may significantly affect the gasoline sorption capacity, which here the role of mesoporous is further highlighted. V meso for amine impregnated sample and free activated carbon was 0.89 and 0.31 Cm 3 / g, respectively. According to the results, the prepared sorbents have a potential capability in uptaking gasoline vapor and with line this, we report a high sorption capacity of 572.56 mg / g. After, four cycles used the sorbent had a high durability and about 99.11% of the initial uptake was maintained. Taking together the synthesized adsorbents as an activated carbon provided an excellent and unique features and enhanced gasoline uptake, therefore its applicability in uptaking gasoline vapor can be substantially considered.


Assuntos
Gasolina , Metenamina , Carvão Vegetal/química , Carvão Mineral , Adsorção , Gases , Aminas
2.
J Hazard Mater ; 416: 125973, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492882

RESUMO

The emerging environmental issues necessitate the engineering of novel and well-designed nanoadsorbents for advanced separation and purification applications. Despite recent advances, the facile synthesis of hierarchical micro-mesoporous metal-organic frameworks (MOFs) with tuned structures has remained a challenge. Herein, we report a simple defect engineering approach to manipulate the framework, induce mesoporosity, and crease large pore volumes in MIL-101(Cr) by embedding graphene quantum dots (GQDs) during its self-assembly process. For instance, MIL-101@GQD-3 (Vmeso: 0.68 and Vtot: 1.87 cm3/g) exhibited 300.0% and 53.3% more meso and total pore volume compared to those of the conventional MIL-101 (Vmeso: 0.17 and Vtot: 1.22 cm3/g), respectively, resulting in 1.7 and 2.8 times greater benzene and toluene loading at 1 bar and 25 °C. In addition, we found that MIL-101@GQD-3 retained its superiority over a wide range of VOC concentrations and operating temperature (25-55 °C) with great cyclic capacity and energy-efficient regeneration. Considering the simplicity of the adopted technique to induce mesoporosity and tune the nanoporous structure of MOFs, the presented GQD incorporation technique is expected to provide a new pathway for the facile synthesis of advanced materials for environmental applications.

3.
Molecules ; 17(6): 6434-48, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22643354

RESUMO

Three azo group-containing Schiff base ligands, namely 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-4-nitrobenzene (2a), 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-2-chloro-4-nitrobenzene (2b) and 1-{3-[(3-hydroxypropylimino) methyl]-4-hydroxyphenylazo}-4-chloro-3-nitrobenzene (2c) were prepared. The ligands were characterized by elemental analysis, FTIR spectroscopy, UV-Vis spectroscopy, ¹³C- and ¹H-NMR spectroscopy and thermogravimetric analysis. Next the corresponding copper(II) and cobalt(II) metal complexes were synthesized and characterized by the physicochemical and spectroscopic methods of elemental analysis, FTIR spectroscopy, UV-Vis spectroscopy, magnetic moment measurements, and thermogravimetric analysis (TGA) and (DSC). The room temperature effective magnetic moments of complexes are 1.45, 1.56, 1.62, 2.16, 2.26 and 2.80 B.M. for complexes 3a, 3b, 3c, 4a 4b, and 4c, respectively, indicating that the complexes are paramagnetic with considerable electronic communication between the two metal centers.


Assuntos
Cobalto/química , Cobre/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Ligantes , Testes de Sensibilidade Microbiana , Ressonância Magnética Nuclear Biomolecular , Bases de Schiff/química , Espectrofotometria Infravermelho , Termogravimetria
4.
Sci Total Environ ; 408(19): 4056-61, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20541790

RESUMO

Although the probability of having breast cancer increases with the age in general, this malignancy affects Iranian women at least one decade younger than their counterparts in other countries. However the underlying risk factors for the discrepancy have not been identified. The aryl hydrocarbon receptor (AhR) mediates the effects of many environmental endocrine disruptors and contributes to the loss of normal ovarian function in polluted environments. This study was aimed to compare the interactions between AhR and other fundamental genes (p53, K-Ras, ER, PgR) in a clinical setting. To conduct the immunohistochemical studies using appropriate monoclonal antibodies, 25 premenopausal invasive ductal carcinoma, 29 postmenopausal invasive ductal carcinoma and 30 breast fibroadenoma were selected retrospectively from 2004 to 2007 in the pathology department of Imam Khomeini hospital complex of Tehran University of Medical Sciences . Higher levels of AhR in epithelial cells of premenopausal patients and breast fibroadenoma emphasized the susceptibility of these cells to environmental-induced tumors. AhR overexpression contributed to ER-/PgR-immunophenotype in young/premenopausal patients but the same pattern was not observed in benign and postmenopausal malignant tumors. It seems that early incidence of breast cancer in Iran is the result of interactions between hormonal and environmental factors.


Assuntos
Neoplasias da Mama/epidemiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adolescente , Adulto , Neoplasias da Mama/etiologia , Neoplasias da Mama/metabolismo , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Monitoramento Epidemiológico , Feminino , Fibroadenoma/epidemiologia , Fibroadenoma/etiologia , Fibroadenoma/metabolismo , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Pessoa de Meia-Idade , Proteína Oncogênica p21(ras)/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
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