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1.
Sci Rep ; 14(1): 19129, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160191

RESUMO

In this research, we reported the synthesis of effective sulphonated sugarcane bagasse (SCB@SA) biosorbent based on agriculture waste materials via a simple diazotization strategy for the removal of methylene blue (MB) and Bismarck Brown R(BB) dyes from waste water samples. First, the sugarcane bagasse (SCB) waste was collected, grinded, and sieved to obtain the desired size. Secondly, the SCB powder is modified with sulfanilinic acid (SA) via the formation of its diazonium salt to introduce sulfonic groups on the SCB surface. Different advanced techniques were applied to characterize the prepared materials before and after the adsorption process viz. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS) and Thermogravimetric analysis (TGA). Different parameters affecting the adsorption process of both MB and BB were studied. Because of the higher correlation coefficient (R2 ≥ 0.999) and lower error functions, the equilibrium MB and BB adsorption isotherms for a single-dye system fit Langmuir with maximum adsorption capacity reaching to 127.48 and 166.75 mg/g for MB and BB, respectively. Moreover, the RL values obtained for both dyes lie between 0 and 1, indicating that MB and BB adsorption by SCB@SA is a favorable process. Besides, the error functions' values of the pseudo-2nd-order are significantly lower than those of the pseudo-1st-order, implying that the adsorption MB and BB onto SCB@SA biosorbent fitted the pseudo-2nd-order kinetic model in a chemosorption manner. In the thermodynamic studies, the adsorption process is spontaneous, exothermic, and has less randomness. In addition, the SCB@SA biosorbent could be reused in five cycles maintaining on suitable adsorption efficiency. Finally, the MB and BB dyes could be adsorbed on the SCB@SA biosorbent via three mechanisms including π-π stacking, columbic attraction, and hydrogen bonding.

2.
Curr Radiopharm ; 17(3): 247-256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192131

RESUMO

BACKGROUND: Employees may be exposed to different kinds of ionizing radiation at work. When ionizing radiation interacts with human cells, it can cause damage to the cells and genetic material. Therefore, one of the scientists' primary objectives has always been to create the best radiation-shielding materials. Glass could offer promising shielding material resulting from the high flexibility of composition, simplicity of production, and good thermal stability. MATERIALS AND METHODS: The melt-quenching technique was used to create a glass having the following formula: 50% P2O5+20% Na2O+20% Fe2O3+10% X, where X = As2O3, SrO, BaO, CdO, and Sb2O3 mol %. The impact of the different heavy metal additions on the structure of the glass networks was studied using FTIR spectroscopy. Glass's ability to attenuate neutrons and/or charged particles has been theoretically investigated. The performance of the developed glass as a shield was examined by a comparison against commercial glass (RS 253 G18), ordinary concrete (OC), and water (H2O). RESULTS: For charged particle radiations (Electrons, Protons, and Alpha), the shielding parameters like the mass stopping power, the projected range, and the effective atomic number were evaluated, where S5/Sb glass achieves the best performance. In the case of Neutrons, the results values reveal that S3/Ba glass ( ΣR = 0.105) is the best-modified glass for neutron shielding. CONCLUSION: Among all the investigated glasses, S5/Sb glass composition has a smaller range and provides superior protection against charged particles. In contrast, the S3/Ba glass composition is a superior choice for shielding against neutron radiation.


Assuntos
Compostos Férricos , Vidro , Metais Pesados , Óxidos , Proteção Radiológica , Vidro/química , Compostos Férricos/química , Metais Pesados/química , Óxidos/química , Humanos
3.
J Hazard Mater ; 403: 123738, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264899

RESUMO

In the present work, aiming to collaborate in the removal of Bypass Cement Dust (BCD) from the environment, we studied a system consisting of three glasses prepared from analytical reagent grade chemicals with the following composition: 20Na2O-20BaCl2-(60-x)B2O3-xBCD, where (x = 0, 10, and 20 %). BCD is an important contributor of many respiratory human health issues. In this work we investigate their optical, physical and gamma-ray shielding properties. The experimental results of mass attenuation coefficients are contrasted with the FLUKA Monte Carlo code and the XCOM database at 0.081, 0.356, 0.662, 1.173, and 1.332 MeV photon energies. Additionally, the mechanical, structural, and optical properties of these glasses were measured. A rising peak with an increase of BCD concentration in the region from 450 cm-1 to 480 cm-1 was observed. The results show that shielding properties such as the mass attenuation coefficient (µm), the effective atomic number (Zeff), and the effective electron density (Nel) increase as BCD fraction increases. The half value layer (HVL), the tenth value layer (TVL), and the mean free path (MFP) decrease as the BCD content increases. It is noticed that 20Na2O-20BaCl2-(60-x)B2O3-xBCD, where (x = 0, 10, and 20 %), has the highest optical conductivity value at x = 20%. It was found that the gradual addition of BCD content increases the hardness of the studied glasses.

4.
Appl Radiat Isot ; 127: 269-274, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28641944

RESUMO

Some sodium-silicate-boro-antimonate glasses having the molecular composition [(20) Na2O - (20) SiO2 - (60-x) B2O3 - (x) Sb2O3 (where x takes the values 0, 5 … or 20)] have been prepared by the melt quenching method. The melting and annealing temperatures were 1500 and 650K respectively. The amorphous nature of the prepared samples was confirmed by using X-ray diffraction analysis. Both the experimental and empirical density and molar volume values showed gradual increase with increasing Sb2O3 content. The empirical densities showed higher values than those obtained experimentally, while the empirical molar volume values appeared lower than those obtained experimentally, which confirm the amorphous nature and randomness character of the studied samples. The experimentally obtained shielding parameters were approximately coincident with those obtained theoretically by applying WinXCom program. At low gamma-ray energies (0.356 and 0.662MeV) Sb2O3 has approximately no effect on the total Mass Attenuation Coefficient, while at high energies it acts to increase the total Mass Attenuation Coefficient gradually. The obtained Half Value Layer and Mean Free Path values showed gradual decrease as Sb2O3 was gradually increased. Also, the Total Mass Attenuation Coefficient values obtained between about 0.8 and 3.0MeV gamma-ray energy showed a slight decrease, as gamma-ray photon energy increased. This may be due to the differences between the Attenuation Coefficients of both antimony and boron oxides at various gamma-ray photon energies. However, it can be stated that the addition of Sb2O3 into sodium-boro-silicate glasses increases the gamma-ray Attenuation Coefficient and the best sample is that contains 20 mol% of Sb2O3, which is operating well at 0.356 and 0.662MeV gamma-ray.

5.
J Bone Joint Surg Br ; 62-B(1): 102-3, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7351425

RESUMO

The effect of the environmental temperature on the healing of fractures was assessed in vertebrae of tails of young albino mice. It was found that fractures in animals kept at 33 degrees Celsius healed very rapidly (bony callus by 14 days) while in animals kept in the cold (8 degrees Celsius) fractures were still at the stage of granulation tissue at this time. Controls were at an intermediate stage. This result might have a clinical application.


Assuntos
Fraturas Ósseas/fisiopatologia , Vértebras Lombares/lesões , Temperatura , Animais , Feminino , Masculino , Camundongos , Cauda/lesões , Fatores de Tempo , Cicatrização
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