• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.190.1-190.1
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• 2016

One of the most serious problems faced by billions of people today is the availability of fresh water. According to statistics, 15% of the world's total output of dye products is discharged into the environment as dye wastewater, which seriously pollutes groundwater resources. For the treatment of chemically and biologically contaminated water the advanced oxidation processes (AOPs) shows the promising action. The main advantage with AOPs is the ability to degrade the organic pollutants to $CO_2$ and $H_2O$. For this degradation process the AOPs generation of powerful and non-selective radicals that may oxidize majority of the organic pollutants present in the water body. To generate the various reactive chemical species such as radicals (${\bullet}OH$, ${\bullet}H$, ${\bullet}O$, ${\bullet}HO_2$) and molecular species ($H_2O_2$, $H_2$, $O_2$) in large amount in water, we have used the atmospheric pressure plasma. Among the reactive and non-reactive species, the hydroxyl radical (${\bullet}OH$) plays important role due to its higher oxidation potential (E0: 2.8 V). Therefore, in this work we have checked the degradation of various dyes such as methyl orange, methylene blue and congo red using different type of atmospheric pressure plasma sources (Indirect jet and direct jet). To check the degradation we have used the UV-visible spectroscopy, HPLC and LC-MS spectroscopy. Further, to estimate role of ${\bullet}OH$ on the degradation of dyes we have studied the molecular dynamic simulation.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.222-227
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• 2008

Citrus aurantium var. amara L., commonly known as 'bitter orange' or 'sour orange', of the family Rutaceae, has traditionally been used in the treatment of various ailments, and it possesses different types of pharmacological properties. As a part of our on-going studies on the plantsfrom the Iranian flora, the extract of C. aurantium var. amara has been studied for its weight lossproperties using the mice model. While the Sep-Pak fraction, 20% methanol (MeOH) in water, of the hydro-methanolic extract of the peels of C. aurantium var. amara fruits, when injectedintraperitoneal (i.p.) at a dose of 10 mg/kg, significantly decreased the level of weight gain of the mice in comparison with control the group (P < 0.01), the Sep-Pak fraction 80% MeOH in water decreased the initial weight of mice by 0.44% in six weeks. The administration of the total extract(10 and 20 mg/kg, i.p.), and the Sep-Pak fractions, 40% and 60% MeOH in water (10 mg/kg, i.p.)did not show any significant change of weight of the test mice. Of the two active fractions, the80% MeOH in water fraction did not show any noticeable adverse effects on mice, and was therefore analysed by reversed-phase preparative high performance liquid chromatography resulting in the isolation and identification of four major components, two coumarins, meranzin hydrate (1) and bergamottin (2), and two flavonoids, xanthomicrol 5,4'-di-methyl ether (tangeritin, 3) and hymenoxin 5,7-di-methyl ether (nobiletin, 4).

• Journal of the Korean Ceramic Society
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• v.49 no.2
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• pp.135-141
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• 2012

To improve the visible-light induced photocatalytic application performances of $TiO_2$, in this study, the $NiS_2$ modied $TiO_2$ composites were prepared by two methods: hydrothermal method and sol-gel method. The composites were denoted as hs-$NiS_2$/$TiO_2$, and sg-$NiS_2$/$TiO_2$ and characterized by XRD, UV-vis absorbance spectra, SEM, TEM, EDX, and BET analysis. The photocatalytic activities under visible light were investigated by the degradation of methyl orange (MO). The photodegradation rate of methyl orange under visible light with $NiS_2$/$TiO_2$ composites was markedly higher than that of pure $TiO_2$, and the effect of hs-$NiS_2$/$TiO_2$ composites was better than that of sg-$NiS_2$/$TiO_2$. The results indicate that the hydrothermal process could partly inhibit the agglomeration of $NiS_2$/$TiO_2$. Thus, the dispersion of nanoparticles was improved, and that the promoting effect of $NiS_2$ could extend the light absorption spectrum toward the visible region.

• Korean Journal of Materials Research
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• v.27 no.9
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• pp.489-494
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• 2017

ZnS powder was synthesized using a relatively facile and convenient glycothermal method at various reaction temperatures. ZnS was successfully synthesized at temperatures as low as $125^{\circ}C$ using zinc acetate and thiourea as raw materials, and diethylene glycol as the solvent. No mineralizers or precipitation processes were used in the fabrication, which suggests that the spherical ZnS powders were directly prepared in the glycothermal method. The phase composition, morphology, and optical properties of the prepared ZnS powders were characterized using XRD, FE-SEM, and UV-vis measurements. The prepared ZnS powders had a zinc blende structure and showed average primary particles with diameters of approximately 20~30 nm, calculated from the XRD peak width. All of the powders consisted of aggregated secondary powders with spherical morphology and a size of approximately $0.1{\sim}0.5{\mu}m$; these powders contained many small primary nanopowders. The as-prepared ZnS exhibited strong photo absorption in the UV region, and a red-shift in the optical absorption spectra due to the improvement in powder size and crystallinity with increasing reaction temperature. The effects of the reaction temperature on the photocatalytic properties of the ZnS powders were investigated. The photocatalytic properties of the as-synthesized ZnS powders were evaluated according to the removal degree of methyl orange (MO) under UV irradiation (${\lambda}=365nm$). It was found that the ZnS powder prepared at above $175^{\circ}C$ exhibited the highest photocatalytic degradation, with nearly 95 % of MO decomposed through the mediation of photo-generated hydroxyl radicals after irradiation for 60 min. These results suggest that the ZnS powders could potentially be applicable as photocatalysts for the efficient degradation of organic pollutants.

• Elastomers and Composites
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• v.45 no.3
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• pp.206-211
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• 2010

Zinc oxide(ZnO) nanoparticles were synthesized by reacting an aqueous-alcoholic zinc nitrate solution to sodium hydroxide under ultrasonic irradiation at room temperature. The fullerene($C_{60}$) and ZnO nanoparticles were heated individually in an electric furnace for two hours at $700^{\circ}C$. The morphology and optical properties of the $C_{60}$ and ZnO nanoparticles were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and ultraviolet/visible (UV-vis) spectroscopy. The photocatalytic activity of the heated and unheated the $C_{60}$ and ZnO nanoparticles for the decomposition of methylene blue(MB), methyl orange(MO) and rhodamine B(RhB) was examined using UV-vis spectroscopy.

• Elastomers and Composites
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• v.49 no.4
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• pp.330-335
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• 2014

Niobium pentoxide ($Nb_2O_5$) nanoparticles were synthesized using niobium (V) chloride and pluronic F108NF as the precursor and templating agent, respectively. The $Nb_2O_5$-graphene nanocomposites were placed in an electric furnace at $700^{\circ}C$ and calcined under Ar atmosphere for 2 h. The morphology, crystallinity, and photocatalytic degradation activity of the samples were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and UV-vis spectroscopy. The $Nb_2O_5$-graphene nanocomposites acted as a photocatalyst in the photocatalytic degradation of organic dyes under 254 nm UV light; the organic dyes used were methylene blue (MB), methyl orange (MO), rhodamine B (RhB), and brilliant green (BG). The photocatalytic degradation kinetics for the aforesaid dyes were determined in the presence of the $Nb_2O_5$-graphene nanocomposites.

• Advances in nano research
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• v.16 no.1
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• pp.41-52
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• 2024

In this study, rare-earth orthoferrites LnFeO₃ were synthesized using a facile hydrothermal reaction and their visible-light-induced photo-Fenton degradation of organics was optimized through Ln variation (Ln = La, Pr, or Gd). The morphological, structural, and chemical characteristics of as-prepared samples were examined in detail by using different methods, including XRD, SEM, TEM, XPS, etc. On the other side, under visible light illumination, the photo-Fenton-like catalytic activities of LnFeO₃ were assessed in terms of the removal of selected organic models, i.e., pharmaceuticals (ketoprofen and tetracycline) and dyes (rhodamine B and methyl orange). As compared with PrFeO₃ or GdFeO₃, the sample of LaFeO₃ displayed more structural distortion, larger specific surface area, and narrower band gap, resulting in its higher photo-Fenton-like catalytic activity toward the degradation of organics. In organic-containing solution, in which the initial solution pH = 5, catalyst dosage = 1 g/L and H₂O₂ concentration = 10 mM, 98.2% of rhodamine B, 31.1% of methyl orange, 67.7% of ketoprofen, or 96.4% of tetracycline was removed after 90-min exposure to simulated visible light. Our findings revealed that variation of Ln site on rare-earth orthoferrites was an effective strategy for optimizing their organic removal via visible-light-induced photo-Fenton reaction.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.49.2-49.2
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• 2011

$PbMoO_4$ nanoparticles were successfully obtained in the presence of ethylene glycol (EG) with the assistance of a prolonged sonication process. The nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and adsorption-desorption $N_2$ isotherms (BET). The catalyst prepared sonochemically showed higher photocatalytic activity than $PbMoO_4$ prepared by solid-state reaction in the degradation reactions of rhodamine B (rhB), indigo carmine (IC), orange G (OG), and methyl orange (MO) under UV-Vis light radiation. In order to elucidate aspects of the degradation mechanism of the organic dyes, some experimental variables were modified such as pH, $O_2$ level in solution, and radiation source. In general, the photocatalytic activity for the degradation of organic dyes followed the sequence IC>OG>rhB>MO.

• Membrane and Water Treatment
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• v.10 no.5
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• pp.361-372
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• 2019

Effect of different alkane based solvents on the stability of emulsion liquid membrane was investigated using normal alkanes (n-hexane, n-heptane, n-octane and n-decane) under various operating parameters of surfactant concentration, emulsification time, internal phase concentration, volume ratio of internal phase to organic phase, volume ratio of emulsion phase to external phase and stirring speed. Results of stability revealed that emulsion liquid membrane containing n-octane as solvent and span-80 (5 % (w/w)) as emulsifying agent presented the highest amount of emulsion stability (the lowest breakage) compared with other solvents; however, operating parameters (surfactant concentration (5% (w/w)), emulsification time (6 min), internal phase concentration (0.05 M), volume ratio of internal phase to organic phase (1/1), volume ratio of emulsion phase to external phase (1/5) and stirring speed (300 rpm)) were also influential on improving the stability (about 0.2% breakage) and on achieving the most stable emulsion. The membrane with the highest stability was employed to extract acridine orange with various concentrations (10, 20 and 40 ppm) from water. The emulsion liquid membrane prepared with n-octane as the best solvent almost removed 99.5% of acridine orange from water. Also, the prepared liquid membrane eliminated completely (100%) other cationic dyes (methylene blue, methyl violet and crystal violet) from water demonstrating the efficacy of prepared emulsion liquid membrane in treatment of dye polluted waters.

• Journal of Pharmacopuncture
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• v.26 no.1
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• pp.10-17
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• 2023

Objectives: Murraya paniculata (family-Rutaceae), popularly known as orange jasmine, is the most important evergreen plant. The Rutaceae family is economically significant due to its diverse edible fruits and essential oils. Methods: Murraya paniculata extracts (MPE) of leaf have been shown to include phenolic compounds, highly oxygenated flavonoids, flavanones, sesquiterpenoids, polymethoxy glycosides, and coumarins. Cyclocitral, methyl salicylate, trans-nerolidol, cubenol, isogermacrene, -cadinol, and cubeb-11-ene are all abundant in MPE. The usages of various parts of this plant, such as bark, leaves and flower, as a remedy for a variety of ailments as widely recorded in the traditional literature. The plant has anti-diabetic, anti-obesity, antibacterial, anti-implantation, anti-oxidative, cytotoxic, anti-diarrheal, antidepressant and anti-anxiety properties and many others. Results: The goal of the review is to reignite interest in this potential plant, encouraging researchers to continue their research in order to uncover novel therapeutic compounds for the treatment and management of a range of infections. The current review provided a comprehensive overview of this traditional unique plant. Conclusion: The review paves a way for exploring its active chemical elements with substantial pharmacological values further for potential benefits of mankind.