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1.
Anim Sci J ; 94(1): e13848, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37392144

RESUMO

In this study, it was aimed to reveal the physical and chemical characterization of the bone structures during body development periods (prepubertal period, period between adolescence and adulthood) and after (young adult period and old adult period) in male and female guinea pigs. In this study, 40 guinea pigs (20 male, 20 female) were used. Morphometric measurements, X-ray fluorescence (XRF) analysis for mineral levels, Brunauer-Emmett-Teller (BET) analysis for surface area, and porosity analysis were applied to the bones. The male guinea pigs had greater values than females in the other three categories, with the exception of the second group, when the females have higher values in morphometric measurements. Ca levels rose up to the third group, as did P levels in the males, peaking in the third group and declining in the fourth. As with phosphorus, there was a progressive rise in females from the first to the fourth group. Fe, Zn, and Sr elements had the greatest values in both genders in the first group. In all four groups, the females had greater Zn levels than males. The highest Ca/P ratio was found in the third male group and the fourth female group. This study revealed that adolescence, adulthood, and gender are effective in the physical and chemical characterization of bone structure in guinea pigs.


Assuntos
Fêmur , Fósforo , Feminino , Masculino , Cobaias , Animais , Análise por Conglomerados
2.
Anat Histol Embryol ; 52(4): 538-545, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36843058

RESUMO

The aim of this study was to determine the physical and chemical characteristics of the bone structures during four developmental periods. Forty Wistar Albino rats (20 male and 20 female) were divided into four groups including prepubertal period (group I), period between adolescence and adulthood (group II) and later (young adult period as group III and old adult period as group IV). The bones were analysed by morphometric measurements, XRF (X-ray fluorescence) analysis for mineral levels and BET analysis (Brunaurer-Emmett-Teller) for surface area and porosity. In morphometric measurements, the GL (greatest length) and the GLC (greatest length from caput femoris) values increased gradually from the first to the fourth group, and these values were higher in the males than the females. Phosphorus and calcium values were higher in the males in adult groups (third and fourth) compared to that for the females; however, they were higher in the females in groups up to adulthood (first and second). While the Ca/P ratio reached the highest value in the second group in the male, it decreased gradually afterwards. In females, the rate, which was close to each other in the first three groups, increased in the fourth group. Surface area size in the female and the male rats was the highest in the second group. In conclusion, changes in the rat bone structure during the development and adulthood periods of the body were revealed, and it was determined that the gender factor was effective in these changes.


Assuntos
Densidade Óssea , Osso e Ossos , Ratos , Masculino , Animais , Feminino , Ratos Wistar , Fêmur , Extremidade Inferior
3.
Int J Phytoremediation ; 24(2): 177-186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34085895

RESUMO

This study aims to investigate the sorptive performance of Pb(II) from water of a novel biochar (WPC) produced by fast pyrolysis under anoxic conditions of wild plants (WP). The maximum Pb(II) sorption capacity of WPC is 50.25 mg/g under determined optimum conditions, which are solution pH 5.0, WPC dose 50 mg, contact time 180 min and solution temperature 50 °C. The sorption kinetics and isotherm data were observed to fit well with the Ho-McKay and Langmuir models, respectively. The thermodynamic parameters (ΔGo, ΔHo and ΔSo) calculated for the WPC-Pb(II) sorption system showed that the process was spontaneous and endothermic. The Pb(II) desorption and regeneration studies of WPC with different desorbent agents was also performed. The findings in this study showed that WP can be used as an abundant precursor in the production of very low cost and eco-friendly biochar, and also that its biochar can be used as an environmentally-friendly sorbent in wastewater treatment. Novelty statementWith increasing population and developing industry in the world, agriculture and industrial wastes are increasing. These wastes create environmental and water pollution and adversely affect the health of living things. Efforts to eliminate these negativities have a negative impact on the world economy. For this purpose, various improvement methods are applied. However, the adsorption method is widely used due to its ease of application, efficiency and economic. In order to make this method more economical, many researchers have carried out researches on the preparation of low-cost adsorbents, especially from vegetable wastes.The novelty of this study is the first reporting to use wild plants as a sustainable precursor to produce a low-cost biochar using the traditional pyrolysis method and to examine its adsorption performance for Pb(II) ion removal from water. I believe that if this study is published, it will create a paradigm in environmental improvement studies on wild plants evaluation.


Assuntos
Poluentes Químicos da Água , Água , Adsorção , Biodegradação Ambiental , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Termodinâmica , Poluentes Químicos da Água/análise
4.
Environ Sci Pollut Res Int ; 28(1): 995-1005, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32827295

RESUMO

We have reported the removal performance from the synthetic aqueous solution of copper of a low-cost and eco-friendly biochar (WHC) produced by facile thermal pyrolysis of wild herbs (WH), a new feedstock, at 550 °C under anoxic conditions. The characteristics of WHC were determined by physicochemical techniques. It exhibited a low BET surface area, total pore volume, and mean pore size of 16.45 m2/g, 0.01 cm3/g, and, 2.34 nm respectively. Batch sorption studies were performed by examining the effects of varying pH, WHC dosage, initial Cu(II) concentrations, interaction time, and temperature to determine optimum removal conditions. In modeling of sorption, data were used the pseudo-first- and pseudo-second-order kinetics and the Langmuir and Freundlich isotherm models. The maximum Cu(II) sorption capacity of WHC was 24.21 mg/g. Thermodynamic parameters were computed for predicting the nature of WHC-Cu(II) sorption system.


Assuntos
Cobre , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cobre/análise , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Água , Poluentes Químicos da Água/análise
5.
Int J Phytoremediation ; 22(13): 1420-1430, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574073

RESUMO

In this study, the removal performance of the Reactive Blue 19 (RB19) dye of the magnetized and non-magnetized industrial tomato solid waste (TW) from the aqueous medium was investigated. The properties of the prepared TW and magnetically modified TW (MTW) bio-sorbents were illuminated using XRD, BET, SEM, VSM, FT-IR and Boehm titration analysis techniques. The optimal conditions for sorption of RB19 by both sorbents were identified. The kinetics and equilibrium data of RB19 sorption by both sorbents were found to match the pseudo-second-order kinetic and Langmuir isotherm models, respectively, with high correlation coefficients. The maximum RB19 sorption capacity under the optimum conditions determined by TW and MTW was determined as 38.76 and 58.14 mg/g, respectively. Thermodynamic parameters calculated for RB19 sorption by both sorbents showed that the processes were spontaneous and exothermic.


Assuntos
Solanum lycopersicum , Poluentes Químicos da Água , Adsorção , Antraquinonas , Biodegradação Ambiental , Corantes , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Cinética , Resíduos Sólidos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
6.
Water Sci Technol ; 2017(1): 170-183, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29698232

RESUMO

The adsorption characteristics of Congo red (CR) dye on activated carbon produced under optimized conditions from tomato paste waste were evaluated. The effects of adsorbent dose, initial dye concentration, contact time, ionic strength and solution temperature on adsorption were investigated. Adsorption kinetic was better described by the pseudo-first order model. Results of the intra-particle diffusion model show that the pore diffusion is not the only rate-limiting step. Adsorption isotherm was well defined by the Langmuir isotherm. The maximum adsorption capacity of the activated carbon was 435 mg g-1 at 328 K. The dimensionless separation factor RL revealed the favorable nature of the isotherm of the activated carbon-dye system. Adsorption energy was found to be 4.20-4.55 kJ mol-1 indicating that the mechanism of adsorption is physical in nature. Thermodynamic studies showed that CR adsorption onto activated carbon was feasible, spontaneous and endothermic. Desorption of the used activated carbon was studied using ethanol as solvent and desorption efficiency of 56.4% was obtained after five cycles. The findings indicated that the activated carbon is a very effective and low-cost adsorbent for removal of CR dye from aqueous solutions.


Assuntos
Carvão Vegetal/química , Vermelho Congo/química , Poluentes Químicos da Água/química , Adsorção , Difusão , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Eliminação de Resíduos Líquidos , Água
7.
Ecotoxicol Environ Saf ; 131: 22-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27177317

RESUMO

Activated carbon (TAC) prepared under optimized conditions with ZnCl2 activation from a new precursor; tomato industrial processing waste (TW), was applied as an adsorbent to remove tetracycline (TC) from aqueous solution. The factors (TAC dosage, initial TC concentration, contact time, ionic strength and solution temperature) affecting the adsorption process were examined at natural pH (5.7) of TAC-TC system in aqueous solution. Kinetic data was found to be best complied by the pseudo-second order model. The isotherm analysis indicated that the equilibrium data could be represented by the Langmuir model. The maximum adsorption capacity was identified as 500.0mgg(-1) at 308K.


Assuntos
Antibacterianos , Carbono/química , Resíduos Industriais , Solanum lycopersicum , Tetraciclina , Purificação da Água/métodos , Adsorção , Cloretos , Concentração de Íons de Hidrogênio , Cinética , Soluções , Temperatura , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Compostos de Zinco
8.
J Hazard Mater ; 153(3): 1275-87, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-17980960

RESUMO

In this study, the effect of temperature on the adsorption of Mn(II), Ni(II), Co(II) and Cu(II) from aqueous solution by modified carrot residues (MCR) was investigated. The equilibrium contact times of adsorption process for each heavy metals-MCR systems were determined. Kinetic data obtained for each heavy metal by MCR at different temperatures were applied to the Lagergren equation, and adsorption rate constants (kads) at these temperatures were determined. These rate constants related to the adsorption of heavy metal by MCR were applied to the Arrhenius equation, and activation energies (Ea) were determined. In addition, the isotherms for adsorption of each heavy metal by MCR at different temperatures were also determined. These isothermal data were applied to linear forms of isotherm equations that they fit the Langmuir adsorption isotherm, and the Langmuir constants (qm and b) were calculated. b constants determined at different temperatures were applied to thermodynamic equations, and thermodynamic parameters such as enthalpy (Delta H), free energy (Delta G), and entropy (Delta S) were calculated and these values show that adsorption of heavy metal on MCR was an endothermic process and process of adsorption was favoured at high temperatures.


Assuntos
Daucus carota , Metais Pesados/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Cinética , Modelos Químicos , Soluções , Espectrofotometria Infravermelho , Termodinâmica
9.
Bioresour Technol ; 99(6): 2009-17, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17470390

RESUMO

The effect of temperature on the adsorption of metanil yellow (MY) (acidic) and methylene blue (MB) (basic) by poplar sawdust was investigated. In addition, the amounts of NaHCO(3), Na(2)CO(3), NaOH and C(2)H(5)ONa adsorbed by 1g of poplar sawdust to determine its surface acidity were also determined. Kinetical data obtained at different temperatures (293 K, 313 K and 333 K) for the adsorption of each dyestuff by poplar sawdust were applied to the pseudo first-order, the pseudo second-order and the intraparticle diffusion equations, and the rate constants of first-order adsorption (k(1)), the rate constants of second-order adsorption (k(2)) and intraparticle diffusion rate constants (k(p)) at these temperatures were calculated, respectively. In addition, isothermal data obtained at different temperatures (293 K, 313 K and 333 K) for the adsorption of each dyestuff by poplar sawdust were applied to thermodynamical equations, and thermodynamical parameters (DeltaG, DeltaH and DeltaS) were also calculated.


Assuntos
Biotecnologia/métodos , Corantes/química , Purificação da Água/instrumentação , Adsorção , Compostos Azo/química , Bioquímica/métodos , Difusão , Resíduos Industriais , Cinética , Azul de Metileno/química , Temperatura , Termodinâmica , Água , Poluentes Químicos da Água , Purificação da Água/métodos , Madeira
10.
J Hazard Mater ; 118(1-3): 141-54, 2005 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-15721538

RESUMO

In this study, the effect of temperature on the adsorption of some dyestuffs [orange II (O-II), crystal violet (CV) and reactive blue 5 (RB5)] and p-nitrophenol (PNP) by chitosan and of O-II and CV by modified chitosan [monocarboxymethylated(mcm)-chitosan] from aqueous solution was investigated. Kinetical data related to the adsorptions of each dyestuff and PNP by chitosan and of O-II and CV by mcm-chitosan were applied to Lagergren and Weber-Morris equations, and adsorption rate constants (kads) and pore diffusion rate constants (kp) were determined, respectively. In addition, Langmuir isotherm constants with experimental data related to the adsorptions of O-II and CV by chitosan and of CV by mcm-chitosan were applied to McKay et al. equation, and external mass transfer coefficients (kf) were also determined. Lastly, chitosan and mcm-chitosan were compared according to their dyestuffs and PNP uptake capabilities. It was seen that mcm-chitosan removed more O-II (99.2%) and RB5 (34.9%) but less CV (3.1%) and PNP (0.9%).


Assuntos
Nitrofenóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Quitosana/química , Difusão , Cinética , Nitrofenóis/química , Temperatura , Purificação da Água/métodos
11.
J Colloid Interface Sci ; 274(2): 398-412, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15144811

RESUMO

The effect of initial concentration, temperature, and shaking rate on the adsorption of three dyestuffs [orange II (O-II), crystal violet (CV), and reactive blue 5 (RB5)] and an ideal adsorbate, p-nitrophenol (PNP), by chitosan (Sigma C-3646) and the effect of temperature on the adsorption of O-II and CV by monocarboxymethylated chitosan (MCM-chitosan) were investigated. Kinetic data obtained for the adsorption of each dyestuff and PNP by chitosan and of O-II and CV by MCM-chitosan at different temperatures were applied to the Lagergren equation, and adsorption rate constants (k(ads)) at these temperatures were determined. These rate constants related to the adsorption of O-II and RB5 by chitosan and of O-II by MCM-chitosan were applied to the Arrhenius equation, and activation energies (E(a)) were determined. In addition, the isotherms for adsorption, at different temperatures, of each dyestuff and PNP by chitosan and of O-II and CV by MCM-chitosan were also determined. These isothermal data were applied to linear forms of isotherm equations that they fit, and isotherm constants were calculated. Because the isotherm curves obtained for the adsorption of O-II and CV by chitosan and of CV by MCM-chitosan fit the Langmuir adsorption isotherm, b constants were applied to thermodynamic equations, and thermodynamic parameters (delta G, delta H, and delta S) were calculated. Lastly, chitosan and MCM-chitosan were compared with respect to the ability to take up the dyestuffs and PNP.


Assuntos
Quitosana/química , Nitrofenóis/química , Adsorção , Corantes/química , Cinética , Microscopia Eletrônica de Varredura , Modelos Químicos , Temperatura , Termodinâmica , Fatores de Tempo
12.
Water Res ; 37(4): 948-52, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12531278

RESUMO

The removal of some heavy metals such as Mn(II), Co(II), Ni(II), and Cu(II) from aqueous solution is studied using a raw kaolinite. The sorption of these metals on kaolinite conformed to linear form of Langmuir adsorption equation. Langmuir C(m) constants for each metal were found as 0.446 mg/g (Mn), 0.919 mg/g (Co), 1.669 mg/g (Ni), 10787 mg/g (Cu) at 25 degrees C, respectively. Also, kinetic and thermodynamic parameters such as enthalpy (deltaH), free energy (deltaG) and entropy (deltaS) were calculated and these values show that adsorption of heavy metal on kaolinite was an endothermic process and the process of adsorption was favoured at high temperatures.


Assuntos
Cobalto/isolamento & purificação , Cobre/isolamento & purificação , Caulim/química , Manganês/isolamento & purificação , Níquel/isolamento & purificação , Purificação da Água/métodos , Adsorção , Cinética , Soluções/química , Fatores de Tempo
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