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Search Results: 1 - 10 of 3521 matches for " Crystal Violet "
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Rapid Adsorption of Crystal Violet onto Magnetic Zeolite Synthesized from Fly Ash and Magnetite Nanoparticles  [PDF]
Olusola S. Amodu, Tunde V. Ojumu, Seteno K. Ntwampe, Olushola S. Ayanda
Journal of Encapsulation and Adsorption Sciences (JEAS) , 2015, DOI: 10.4236/jeas.2015.54016
Abstract: This work reports the adsorption of crystal violet (CV) dye onto magnetic zeolite (MZ) nanoparticles, synthesized by direct fusion of fly ash (FA) and magnetite particles. The synthesised MZ showed high capacity for CV dye adsorption, removing 95% of the dye at an equilibrium adsorption time of 10 min and 25℃. The effects of adsorbent dosage, dye concentration, and pH, on adsorption were evaluated. Adsorption data were best described by the Langmuir adsorption isotherm (R2 = 0.9986), while the adsorption kinetics was best fitted by the pseudo-second-order kinetic model (R2 = 0.9999). Application of the MZs synthesised from inexpensive resources such as FA could ensure the sustainability and cost effectiveness of treating industrial effluent containing basic dyes, especially effluent from the textile industries.
New indicator reaction for kinetic determination of micro amounts of Sn(II)
RANGEL P. IGOV,VIOLETA D. MITIC,TODOR G. PECEV,VESNA P. STANKOV-JOVANOVIC
Journal of the Serbian Chemical Society , 2001,
Abstract: A new reaction is suggested and a new method is elaborated for determination of micro amounts of Sn(II) based on its inhibiting effect on the oxidation of {4-bis[n-(dimethylamino) phenyl ]methylene-2,5-cyclohexadiene-1-ilydene}dimethyl-ammonium chloride (crystal violet CV) by H2O2. The method sensibility is 0.4 mg/cm3. The probable relative error is 2.8 12.8 % for Sn(II) in the concentration interval of 3 to 0.8 mg/cm3. The kinetic equation for this process is given. The influence of some other ions on the reaction rate was tested. The method was applied to the determination of Sn(II) in a sample of microalloy.
Multi-species biofilm of Candida albicans and non-Candida albicans Candida species on acrylic substrate
Pathak, Apurva K;Sharma, Sanjay;Shrivastva, Pallavi;
Journal of Applied Oral Science , 2012, DOI: 10.1590/S1678-77572012000100013
Abstract: objective: in polymicrobial biofilms bacteria extensively interact with candida species, but the interaction among the different species of the candida is yet to be completely evaluated. in the present study, the difference in biofilm formation ability of clinical isolates of four species of candida in both single-species and multi-species combinations on the surface of dental acrylic resin strips was evaluated. material and methods: the species of candida, isolated from multiple species oral candidiasis of the neutropenic patients, were used for the experiment. organisms were cultured on sabouraud dextrose broth with 8% glucose (sdb). biofilm production on the acrylic resins strips was determined by crystal violet assay. student's t-test and anova were used to compare in vitro biofilm formation for the individual species of candida and its different multi-species combinations. results: in the present study, differences between the mean values of the biofilm-forming ability of individual species (c. glabrata>c. krusei>c. tropicalis>c. albicans) and in its multi-species' combinations (the highest for c. albicans with c. glabrata and the lowest for all the four species combination) were reported. conclusions: the findings of this study showed that biofilm-forming ability was found greater for non-candida albicans candida species (ncac) than for c. albicans species with intra-species variation. presence of c. albicans in multi-species biofilms increased, whereas; c. tropicalis decreased the biofilm production with all other ncac species.
Estudo da sor??o do corante cati?nico violeta cristal por espuma de poliuretano em meio aquoso contendo dodecilsulfato de sódio
Mori, Mariana;Cassella, Ricardo J.;
Química Nova , 2009, DOI: 10.1590/S0100-40422009000800011
Abstract: this work presents a detailed study about the sorption of crystal violet (cv) cationic dye onto polyether type polyurethane foam (puf). the sorption process was based on the formation of an ionic-pair between cationic dye and dodecylsulfate anion (sds), which presented high affinity by puf. set-up employed in the study was built up by adjusting a 200 mg cylinder of puf to the arm of an overhead stirrer. the system was characterized in relation to equilibrium and kinetic aspects and it was modeled by employing langmuir and freundlich isotherms. obtained results showed that the ratio between sds and mb concentrations played an important role on the sorption process. according to results found it was possible to retain up to 3.4 mg of dye from 200 ml of a 5.0 x 10-5 mol l-1 cv solution containing 1.25 x 10-4 mol l-1 sds, which represented a removal efficiency of around 92%.
Identifica??o e quantifica??o do cristal violeta em aguardentes de mandioca (tiquira)
Santos, Geraldino da Silva;Marques, Edmar Pereira;Silva, Hildo Ant?nio dos Santos;Bezerra, Cícero Wellington Brito;Marques, Aldaléa Brandes;
Química Nova , 2005, DOI: 10.1590/S0100-40422005000400005
Abstract: tiquira is a traditional homemade alcoholic distillate produced in the maranh?o state (brazil), gotten from cassava (manihot esculenta, crantz.). it can be normally found on street markets. due to the addition of tangerine leaves, the original tiquira has a bluish color. samples of this beverage were acquired in the local trade and analyzed from the spectroanalytical point of view. the results indicated that these drinks had been adulterated by the addition of crystal violet, a potencialy hazardous compound. the identification and quantification of crystal violet in 10 spiked samples was accomplished by uv-vis spectrophotometry through the standard addition method. in order to verify the efficiency of the proposed method, experiments on the quantification and recovery were carried out and the results indicated a content of crystal violet in the 10-6 to 10-7 mol l-1 range.
Interactions between crystal violet and AOT in aqueous solutions and in AOT/isooctane/water microemulsions
Xiaojuan Hao,Xueqin An,Zhiyun Chen,Weiguo Shen
Chinese Science Bulletin , 2004, DOI: 10.1007/BF02900312
Abstract: The absorbance of crystal violet (CV) in a series of aqueous solutions and a series of sodium bis(2-ethyl-hexyl) sulfosuccinate (AOT)/isooctane/water microemulsions has been determined. Association models have been used to analyse the experimental data to obtain the association constants of CV and AOT in the above two media. It was found that about up to 57% CV was associated by AOT in AOT/ isooctane/water microemulsions, which reduced the reaction rate of alkaline fading of crystal violet in the microemulsions.
Adsorption studies on the removal of cationic dye from shrimp shell using chitin
Soheir A. Khedr,Mona A. Shouman,Amina A. Attia
Biointerface Research in Applied Chemistry , 2013,
Abstract: Recent developments have given positive indications that biomaterials, in their nature or modified states are effective, environmentally friendly adsorbents of pollutants. This study investigates the chitin obtained from shrimp shell as an adsorbent for Crystal violet dye removal. Effect of various physico-chemical parameters such as contact time, initial dye concentration (250- 75 mg/L), pH (2-10) and temperature (293-333K) were investigated. Experimental data were analyzed by using Langmuir, Freundlich, Temkin and Dubinin – Radushkevich adsorption models. Equilibrium data were fitted well with the Langmuir model with maximum monolayer adsorption capacity of 37.02 mg/g. The kinetics of Crystal violet adsorption followed the pseudo-second order rate expression which suggests that intraparticle diffusion plays a significant role in the adsorption mechanism. Thermodynamic parameters, such as changes in Gibbs free energy ( G°), enthalpy ( H°) and entropy ( S°) were calculated to appreciate the nature of adsorption process. The surface morphology of chitin obtained from shrimp shell was studied using FTIR, SEM, and TG - DTG. The results of this work indicate that the chitin extracted from natural materials constitutes a promising and efficient low cost adsorbent for the removal of dyes from aqueous effluents.
Photocatalytic Properties of Pt/GaP Nanoparticles under Visible Light Irradiation
HUANG Yi-Chun, ZHANG Zhao-Chun, JIANG Hui-Yi
无机材料学报 , 2011, DOI: 10.3724/sp.j.1077.2011.00579
Abstract: Gallium phosphide (GaP) nanoparticle was synthesized by the reaction of sodium phosphide and gallium chloride in dimethylbenzene. GaP―supported platinum photocatalysts, Pt(0.80wt%)/GaP and Pt(4.2wt%)÷GaP nanoparticles, were prepared by the simple reduction of chloroplatinic acid (H2PtCl6) with hydrazine hydrate (N2H4·H2O). The photocatalytic activities of GaP and Pt/GaP nanoparticles for the decomposition of crystal violet were investigated under visible light irradiation. The results indicate that GaP, Pt(0.80wt%)/GaP and Pt(4.2wt%)/GaP nanoparticles can harness visible light to decompose crystal violet in aqueous solution. The photocatalytic activity of Pt(0.80wt%)/GaP is better than that of GaP while the photocatalytic activity of GaP is better than that of Pt(4.2wt%)/GaP. The Pt coverage has an important effect on the photocatalytic activity of Pt/GaP nanoparticles.
MBDS Solvent: An Improved Method for Assessment of Biofilms  [PDF]
Greg Tram, Victoria Korolik, Christopher J. Day
Advances in Microbiology (AiM) , 2013, DOI: 10.4236/aim.2013.32030
Abstract:

Biofilms are recognised as an important contributor to bacterial resistance towards traditional antimicrobial treatments. Assessment of biofilm formation currently relies on a 96 well microtitre plate assay, which usually involves the colourimetric detection of stain (typically crystal violet) removed from previously stained biofilm. The amount of crystal violet released is then used as a quantitative indicator of the amount of biofilm formed. Currently, this is achieved by solubilisation of the stain by ethanol which results in partial decolourisation of the crystal violet stained biofilm which impacts the accuracy and reproducibility of this method. Herein, we describe a modified biofilm dissolving solution (MBDS) which produces a more uniform and reproducible colour release from stained biofilm through solubilisation of the biofilm architecture itself. Here we use crystal violet stained biofilms of P. aeruginosa strain PA0-1, to demonstrate an approximate two fold increase in crystal violet release by MBDS, as compared to ethanol treatment. In addition, when ethanol decolourised biofilms were treated again with MBDS, an almost equal amount of remnant crystal violet was recovered by dissolving the biofilm and the stain trapped within it. These results were reflected in microscopic analysis of ethanol treated and MBDS treated biofilm. Similar results were obtained when MBDS was used to decolourise and dissolve the biofilms of a number of other bacterial species highlighting the advantages of MDBS as a universal solvent for the colour detection of biofilm.

Synthesis of Nano-Titanium Tannate as an Adsorbent for Crystal Violet Dye, Kinetic and Equilibrium Isotherm Studies  [PDF]
Taha M. Elmorsi
Journal of Environmental Protection (JEP) , 2015, DOI: 10.4236/jep.2015.612126
Abstract: The purpose of this study was to prepare nano-titanium tannate complex (TTC) and to investigate its adsorption capacity for removal of cationic dyes such as crystal violet (CV) dye. The morphology and the main elements of TTC adsorbent were characterized by scanning electron microscopy (SEM-EDS), while its crystal structure was characterized by X-ray diffraction (XRD). Also, FT-IR spectroscopy study structural aspects of TTC. A “cotton-ball”-like and porous surface structure of titanium tannate complex (TTC) with nanoparticle size of 16.18 nm show high capability for absorbing crystal violet dye. The effect of several parameters such as contact time, initial concentrations of CV, solution pH and the amount of TTC was investigated. Three different kinetic equations such as pseudo-first order, pseudo-second order and intraparticle diffusion were used to study the order and the mechanism of the adsorption process. The adsorption of CV dye followed pseudo- second order equation. Moreover, equilibrium data were tested with four adsorption isotherm models namely, Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R). Langmuir was the best fit for the data with maximum capacity as 58.8 mg/g. The results of Separation factor, Surface coverage and standard free energy (ΔG°) indicated that adsorption of CV onto TTC was favorable with fast rate and spontaneous physical adsorption process.
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