Degradation pathway of malachite green in a novel dual-tank photoelectrochemical catalytic reactor.

Science.gov (United States)

Diao, Zenghui; Li, Mingyu; Zeng, Fanyin; Song, Lin; Qiu, Rongliang

2013-09-15

A novel dual-tank photoelectrochemical catalytic reactor was designed to investigate the degradation pathway of malachite green. A thermally formed TiO₂/Ti thin film electrode was used as photoanode, graphite was used as cathode, and a saturated calomel electrode was employed as the reference electrode in the reactor. In the reactor, the anode and cathode tanks were connected by a cation exchange membrane. Results showed that the decolorization ratio of malachite green in the anode and cathode was 98.5 and 96.5% after 120 min, respectively. Malachite green in the two anode and cathode tanks was oxidized, achieving the bipolar double effect. Malachite green in both the anode and cathode tanks exhibited similar catalytic degradation pathways. The double bond of the malachite green molecule was attacked by strong oxidative hydroxyl radicals, after which the organic compound was degraded by the two pathways into 4,4-bis(dimethylamino) benzophenone, 4-(dimethylamino) benzophenone, 4-(dimethylamino) phenol, and other intermediate products. Eventually, malachite green was degraded into oxalic acid as a small molecular organic acid, which was degraded by processes such as demethylation, deamination, nitration, substitution, addition, and other reactions. Copyright © 2013 Elsevier B.V. All rights reserved.

Malachite Green Adsorption by Spent Coffee Grounds

Science.gov (United States)

Syamimie Atirah Mat, Siti; Zati Hanani Syed Zuber, Sharifah; Rahim, Siti Kartini Enche Ab; Sohaimi, Khairunissa Syairah Ahmad; Halim, Noor Amirah Abdul; Fauziah Zainudin, Nor; Aida Yusoff, Nor; Munirah Rohaizad, Nor; Hidayah Ishak, Noor; Anuar, Adilah; Sarip, Mohd Sharizan Md

2018-03-01

In this work, the ability of spent coffee grounds (SCG) as a low-cost adsorbent to remove malachite green (MG) from aqueous solutions was studied. Batch adsorption tests were carried out to observe the effect of various experimental parameters such as contact time, initial concentration of malachite green and adsorbent dosage on the removal of dye. The results obtained show that the percentage of dye removal will decreased with the increased of initial concentration of dye in the range of 50 mg/L to 250 mg/L. Besides, percentage removal of dye was also found to be increased as the contact time increased until it reached equilibrium condition. The results also showed that the adsorbent dosage in range of 0.2 g to 1.0 g is proportional to the percentage removal of malachite green dye. Study on the kinetic adsorption and isotherm adsorption has also been investigated. The adsorption isotherm data were described by Langmuir isotherm with high-correlation coefficients while the experimental data showed the pseudo-second-order kinetics model was the best model for the adsorption of MG by SCG with the coefficients of correlation R2 > 0.9978.

Photodegradation of Malachite Green by Nanostructured Bi2WO6 Visible Light-Induced Photocatalyst

OpenAIRE

Yijie Chen; Yaqin Zhang; Chen Liu; Aimin Lu; Weihua Zhang

2012-01-01

Bi2WO6 photocatalyst was first utilized to degrade malachite green. The effects of the concentration of malachite green, the pH value, and the concentration of Bi2WO6 on the photocatalytic efficiency were investigated. This study presents a strategy to eliminate highly toxic and persistent dyes such as malachite green.

Quirks of dye nomenclature. 6. Malachite green.

Science.gov (United States)

Cooksey, C J

2016-08-01

Malachite green was discovered independently by two researchers in Germany in the 19(th) century and found immediate employment as a dye and a pigment. Subsequently, other uses, such as staining biological specimens, emerged. A much later application was the control of fungal and protozoan infections in fish, for which the dye remains popular, although illegal in many countries owing to a variety of toxicity problems. In solution, malachite green can exist as five different species depending on the pH. The location of the positive charge of the colored cation on a carbon atom or a nitrogen atom is still debated. The original names of this dye, and their origins, are briefly surveyed.

TOXICOLOGICAL STUDIES ON MALACHITE GREEN - A TRIPHENYLMETHANE DYE

DEFF Research Database (Denmark)

Cleinmensen, Steen; Jensen, Jørn C.; Jensen, Niels J.

1984-01-01

The oral LD50 for malachite green oxalate was found to be 275 mg/kg in rats while the approximate lethal dose for NMRI mice was 50 mg/kg. No systemic effects were seen after dermal application of 2,000 mg/kg. Repeated administration in the diet for 28 days to rats produced only minor changes...... in serum urea and aspartate aminotransferase levels. The rats at the highest dose level showed decreased weight gain and appeared clinically to have elevated motor activity. No sex differences were observed in either acute or prolonged experiments. In accord with human experience malachite green...

Morphological changes in vesicles and release of an encapsulated compound triggered by a photoresponsive Malachite Green leuconitrile derivative.

Science.gov (United States)

Uda, Ryoko M; Hiraishi, Eri; Ohnishi, Ryo; Nakahara, Yoshio; Kimura, Keiichi

2010-04-20

Photoinduced morphological changes in phosphatidylcholine vesicles are triggered by a Malachite Green leuconitrile derivative dissolved in the lipidic membrane, and are observed at Malachite Green derivative/lipid ratios Malachite Green derivative is a photoresponsive compound that undergoes ionization to afford a positive charge on the molecule by UV irradiation. The Malachite Green derivative exhibits amphiphilicity when ionized photochemically, whereas it behaves as a lipophilic compound under dark conditions. Cryo-transmission electron microscopy was used to determine vesicle morphology. The effects of the Malachite Green derivative on vesicles were studied by dynamic light scattering and fluorescence resonance energy transfer. Irradiation of vesicles containing the Malachite Green derivative induces nonspherical vesicle morphology, fusion of vesicles, and membrane solubilization, depending on conditions. Furthermore, irradiation of the Malachite Green derivative induces the release of a vesicle-encapsulated compound.

A nanosilver-based spectrophotometric method for determination of malachite green in surface water samples.

Science.gov (United States)

Sahraei, R; Farmany, A; Mortazavi, S S; Noorizadeh, H

2013-07-01

A new spectrophotometric method is reported for the determination of nanomolar level of malachite green in surface water samples. The method is based on the catalytic effect of silver nanoparticles on the oxidation of malachite green by hexacyanoferrate (III) in acetate-acetic acid medium. The absorbance is measured at 610 nm with the fixed-time method. Under the optimum conditions, the linear range was 8.0 × 10(-9)-2.0 × 10(-7) mol L(-1) malachite green with a correlation coefficient of 0.996. The limit of detection (S/N = 3) was 2.0 × 10(-9) mol L(-1). Relative standard deviation for ten replicate determinations of 1.0 × 10(-8) mol L(-1) malachite green was 1.86%. The method is featured with good accuracy and reproducibility for malachite green determination in surface water samples without any pre-concentration and separation step.

Biosorption of malachite green onto Haematococcus pluvialis observed through synchrotron-FTIR microspectroscopy.

Science.gov (United States)

Liu, J H; Zhang, L; Zha, D C; Chen, L Q; Chen, X X; Qi, Z M

2018-06-28

Microalgae have emerged as promising biosorbents for the treatment of malachite green in wastewater. However, the underlying mechanism for the biosorption of malachite green onto microalgae is still unclear and needs further intensive study. In this work, synchrotron Fourier-transform infrared (synchrotron-FTIR) microspectroscoy in combination with biochemical assay is employed to evaluate malachite green removal efficiency (95.2%, 75.6% and 66.5%) by three stages of Haematococcus pluvialis. Meanwhile, the various vital changes of algal cells including lipids, proteins, polysaccharides and carotenoids, is distinguished and quantified in situ. This study illustrates that synchrotron-FTIR microspectroscopy is an effective and powerful tool to scrutinize the mechanism for the interactions between the malachite green dye and microalgal cells and it even provides an effective and none-invasive new approach to screen potentially proper biosorbents for the removal of dyes from wastewater. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Removal of Malachite Green from water using hydrothermally carbonized pine needles

KAUST Repository

Hammud, Hassan Hasan; Shmait, Abeer; Hourani, Nadim

2015-01-01

Hydrothermal carbonization of pine needles (HTC-PN) and their oxidized-activated form HTC-APN are prepared and applied for the adsorption of Malachite Green (MG) in aqueous solution. The HTC materials were characterized by thermal and TEM analysis

Extractive spectrophotometric determination of uranium with malachite green

International Nuclear Information System (INIS)

Dubey, S.C.; Nadkarni, M.N.

1977-01-01

A sensitive spectrophotometric method based on the extraction of a uranium-benzoate-Malachite Green complex by chlorobenzene is described. The absorption maximum is at 635 nm and the molar absorptivity is 8.3 x 10 4 1. mole -1 cm -1 . A preliminary separation of uranium by extraction with methyl isobutyl ketone from acid-deficient aluminium nitrate solution is used to avoid interferences. An aliquot of the extract in then diluted with chlorobenzene and shaken with benzoate buffer containing Malachite Green (MG). The method has been applied for the determination of uranium in a synthetic leach solution. The complex extracted is probably [U0 2 (C 6 H 5 C00 3 - ][MG + ]. (author)

Analysis of pure and malachite green doped polysulfone sample using FT-IR technique

Science.gov (United States)

Nayak, Rashmi J.; Khare, P. K.; Nayak, J. G.

2018-05-01

The sample of pure and malachite green doped Polysulfone in the form of foil was prepared by isothermal immersion technique. For the preparation of pure sample 4 gm of Polysulfone was dissolved in 50 ml of Dimethyl farmamide (DMF) solvent, while for the preparation of doped sample 10 mg, 50 mg and 100 mg Malachite Green was mixed with 4 gm of Polysulfone respectively. For the study of structural characterization of these pure and doped sample, Fourier Transform Infra-Red Spectroscopy (FT-IR) technique was used. This study shows that the intensity of transmittance decreases as the ratio of doping increases in pure polysulfone. The reduction in intensity of transmittance is clearly apparent in the present case more over the bands were broader which indicates towards charge transfer interaction between the donar and acceptor molecule.

Scientific opinion: Malachite green in food

NARCIS (Netherlands)

Hoogenboom, L.A.P.

2016-01-01

Malachite green (MG) has been used globally in aquaculture but is not registered for use in food-producing animals in the European Union. The European Commission requested EFSA to evaluate whether a reference point for action (RPA) of 2 μg/kg for the sum of MG and its major metabolite leucomalachite

Extractive spectrophotometric determination of uranium with malachite green

Energy Technology Data Exchange (ETDEWEB)

Dubey, S C; Nadkarni, M N [Bhabha Atomic Research Centre, Bombay (India). Fuel Reprocessing Div.

1977-04-01

A sensitive spectrophotometric method based on the extraction of a uranium-benzoate-Malachite Green complex by chlorobenzene is described. The absorption maximum is at 635 nm and the molar absorptivity is 8.3 x 10/sup 4/1. mole /sup -1/ cm/sup -1/. A preliminary separation of uranium by extraction with methyl isobutyl ketone from acid-deficient aluminium nitrate solution is used to avoid interferences. An aliquot of the extract in then diluted with chlorobenzene and shaken with benzoate buffer containing Malachite Green (MG). The method has been applied for the determination of uranium in a synthetic leach solution. The complex extracted is probably (U0/sub 2/(C/sub 6/H/sub 5/C00/sub 3//sup -/)(MG/sup +/).

Molecularly imprinted polymer for selective extraction of malachite green from seawater and seafood coupled with high-performance liquid chromatographic determination.

Science.gov (United States)

Lian, Ziru; Wang, Jiangtao

2012-12-01

In this paper, a highly selective sample cleanup procedure combining molecular imprinting technique (MIT) and solid-phase extraction (SPE) was developed for the isolation of malachite green in seawater and seafood samples. The molecularly imprinted polymer (MIP) was prepared using malachite green as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The imprinted polymer and non-imprinted polymer were characterized by scanning electron microscope and static adsorption experiments. The MIP showed a high adsorption capacity and was used as selective sorbent for the SPE of malachite green. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chromatography with diodearray detection for the analysis of malachite green in seawater and seafood samples was also established. Finally, five samples were determined. The results showed that malachite green concentration in one seawater sample was at 1.30 μg L⁻¹ and the RSD (n=3) was 4.15%. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

[Biosorption of crystal violet and malachite green by Rhodotorula graminis Y-5].

Science.gov (United States)

Hu, Rong; Huang, Jian-Bo; Yang, Zhou-Ping; Cheng, Zi-Zhang; Jing, De-Jun; Huang, Qian-Ming

2011-12-01

With a shaker, this paper studied the characteristics of the biosorption of crystal violet and malachite green by Rhodotorula graminis Y-5 under different adsorption time, initial pH, and temperature, as well as the desorption and recycling use of the dyes. The biosorption of crystal violet and malachite green by R. graminis Y-5 had the peaks (93.8% and 87.7%, respectively) at pH 7.0, dye concentration 50 mg x L(-1), 150 r x min(-1), 30 degrees C, and lasting 10 hours. After desorption, the biosorption rate of crystal violet and malachite green by R. graminis was 85.5% and 78.5%, respectively, indicating that the biosorption of crystal violet and malachite green was reversible, and the recycling use of the dyes by R. graminis was quite good, i. e., the dyes were renewable and could be recycled. Biosorption could be the mechanism of the decolorization of the dyes. The dyes were mostly adsorbed on the R. graminis surface -OH. The adsorption process was fast, efficient, and reversible, suggesting that R. graminis had a high potential for waste water treatment.

Determination of malachite green residues in the eggs, fry, and adult muscle-tissue of rainbow-trout (Oncorhynchus-mykiss)

Science.gov (United States)

Allen, John L.; Gofus, J.E.; Meinertz, Jeffery R.

1994-01-01

Malachite green, an effective antifungal therapeutant used in fish culture, is a known teratogen. We developed a method to simultaneously detect both the chromatic and leuco forms of malachite green residues in the eggs, fry, and adult muscle tissue of rainbow trout (oncorhynchus mykiss). Homogenates of these tissues were fortified with [c-14] malachite green chloride and extracted with 1% (v/v) acetic acid in acetonitrile or in methanol. The extracts were partitioned with chloroform, dried, redissolved in mobile phase, and analyzed by liquid chromatography (lc) with postcolumn oxidation of leuco malachite green to the chromatic form. Lc fractions were collected every 30 s for quantitation by scintillation counting. Recoveries of total [c-14] malachite green chloride residue were 85 and 98% in eggs fortified with labeled malachite green at concentrations of 0.5 And 1.00 Mug/g, respectively; 68% in fry similarly fortified at a concentration of 0.65 Mug/g; and 66% in muscle homogenate similarly fortified at a level of 1.00 Mug/g. The method was tested under operational conditions by exposing adult rainbow trout to 1.00 Mg/l [c-14] malachite green chloride bath for 1 h. Muscle samples analyzed by sample oxidation and scintillation counting contained 1.3 And 0.5 Mug/g total malachite green chloride residues immediately after exposure and after a 5-day withdrawal period, respectively.

Ocular hazards of the colors used during the festival-of-colors (Holi) in India--malachite green toxicity.

Science.gov (United States)

Velpandian, T; Saha, K; Ravi, A K; Kumari, S S; Biswas, N R; Ghose, S

2007-01-10

The objective of this study was to evaluate the nature of the colors used and their toxicity to the eye upon exposure to them during celebration of Holi (our festival-of-colors). Color powders and formulations were procured at random in and around Delhi during the festival. The green/bluish-green colors reported with the higher incidence of ocular toxicity were subjected for further evaluation. Eyewash fluid collected from the patients exposed to the colors was also subjected for analysis. This study was further extended to evaluate the corneal penetration of malachite green using goat cornea in perfusion chamber. In 16/18 color samples collected, malachite green or 4-[(4-dimethylaminophenyl)-phenyl-methyl]-N,N-dimethyl-aniline was detected at different concentrations. In the eyewash fluid of four patients, HPLC estimation confirmed the presence of malachite green at concentrations of 1.3, 0.18, 3.5 and 5.4 microg in 250 ml which was responsible for its reported toxicity. The in vitrotrans-corneal penetration studies did not show any detectable amount of malachite green in effluent fluid-in vitro tissue retention studies revealed that increasing the contact time increases tissue concentration. After 2 min of exposure, the tissue concentration was significantly higher. To conclude, malachite green was extensively used in our festival of Holi and has caused severe ocular irritation with epithelial defect upon exposure, though it did not penetrate through the cornea-further in vitro and in vivo studies are required on colors used in Holi.

Molecularly imprinted polymer for selective extraction of malachite green from seawater and seafood coupled with high-performance liquid chromatographic determination

International Nuclear Information System (INIS)

Lian Ziru; Wang Jiangtao

2012-01-01

Highlights: ► The malachite green molecularly imprinted polymer (MG-MIP) was prepared. ► The characteristics and regeneration property of MIP were studied. ► An off-line method for MG was developed using MIP as solid-phase extraction. ► The MG concentrations from seawater and seafood samples were determined. - Abstract: In this paper, a highly selective sample cleanup procedure combining molecular imprinting technique (MIT) and solid-phase extraction (SPE) was developed for the isolation of malachite green in seawater and seafood samples. The molecularly imprinted polymer (MIP) was prepared using malachite green as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The imprinted polymer and non-imprinted polymer were characterized by scanning electron microscope and static adsorption experiments. The MIP showed a high adsorption capacity and was used as selective sorbent for the SPE of malachite green. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chromatography with diodearray detection for the analysis of malachite green in seawater and seafood samples was also established. Finally, five samples were determined. The results showed that malachite green concentration in one seawater sample was at 1.30 μg L −1 and the RSD (n = 3) was 4.15%.

Confirmatory analysis of malachite green, Leucomalachite green, crystal violet and leucocrystal violet in salmon by liquid chromatography-tandem mass spectrometry

NARCIS (Netherlands)

Dowling, A.P.G.; Mulder, P.P.J.; Duffy, C.; Regan, L.; Smyth, M.R.

2007-01-01

A method has been developed to analyse for malachite green (MG), leucornalachite green (LMG), crystal violet (CV) and leucocrystal violet (LCV) residues in salmon. Salmon samples were extracted with acetonitrile:Mclllvain pH 3 buffer (90: 10 v/v), sample extracts were purified on a Bakerbond strong

Extraction photometric determination of uranium (6) with use of malachite green

International Nuclear Information System (INIS)

Stepanenko, Yu.V.; Bagdasarov, K.N.; Shchemeleva, G.G.

1975-01-01

A study of the reaction between uranium (6) and malachite green in the presence of sodium benzoate has indicated that, in a weakly acid medium (pH 4.5 to 5.5), the reaction yields a poorly soluble greenish compound which tends to be extracted by a 1-to-1 mixture of benzene and chloroform. The compound comprises uranium, a benzoate and a malachite green in a ratio of 1/3/1. A method has been developed for an extraction-photometric determination of uranium in metallic lead

Extraction photometric determination of uranium (6) with use of malachite green

Energy Technology Data Exchange (ETDEWEB)

Stepanenko, Yu V; Bagdasarov, K N; Shchemeleva, G G [Rostovskij-na-Donu Gosudarstvennyj Univ. (USSR)

1975-12-01

A study of the reaction between uranium (6) and malachite green in the presence of sodium benzoate has indicated that, in a weakly acid medium (pH 4.5 to 5.5), the reaction yields a poorly soluble greenish compound which tends to be extracted by a 1-to-1 mixture of benzene and chloroform. The compound comprises uranium, a benzoate and a malachite green in a ratio of 1/3/1. A method has been developed for an extraction-photometric determination of uranium in metallic lead.

Fenton-Like Oxidation of Malachite Green Solutions: Kinetic and Thermodynamic Study

Directory of Open Access Journals (Sweden)

Saeedeh Hashemian

2013-01-01

Full Text Available Oxidation by Fenton-like (Fe3+/H2O2 reactions is proven to be an economically feasible process for destruction of a variety of hazardous pollutants in wastewater. In this study, the degradation and mineralization of malachite green dye are reported using Fenton-like reaction. The effects of different parameters like pH of the solution, the initial concentrations of Fe3+, H2O2, and dye, temperature, and added electrolytes (Cl− and on the oxidation of the dye were investigated. Optimized condition was determined. The efficiency of 95.5% degradation of MAG after 15 minutes of reaction at pH 3 was obtained. TOC removal indicates partial and insignificant mineralization of malachite green dye. The results of experiments showed that degradation of malachite green dye in Fenton-like oxidation process can be described with a pseudo-second-order kinetic model. The thermodynamic constants of the Fenton oxidation process were evaluated. The results implied that the oxidation process was feasible, spontaneous, and endothermic. The results will be useful for designing the treatment systems of various dye-containing wastewaters.

Organic additives stabilize RNA aptamer binding of malachite green.

Science.gov (United States)

Zhou, Yubin; Chi, Hong; Wu, Yuanyuan; Marks, Robert S; Steele, Terry W J

2016-11-01

Aptamer-ligand binding has been utilized for biological applications due to its specific binding and synthetic nature. However, the applications will be limited if the binding or the ligand is unstable. Malachite green aptamer (MGA) and its labile ligand malachite green (MG) were found to have increasing apparent dissociation constants (Kd) as determined through the first order rate loss of emission intensity of the MGA-MG fluorescent complex. The fluorescent intensity loss was hypothesized to be from the hydrolysis of MG into malachite green carbinol base (MGOH). Random screening organic additives were found to reduce or retain the fluorescence emission and the calculated apparent Kd of MGA-MG binding. The protective effect became more apparent as the percentage of organic additives increased up to 10% v/v. The mechanism behind the organic additive protective effects was primarily from a ~5X increase in first order rate kinetics of MGOH→MG (kMGOH→MG), which significantly changed the equilibrium constant (Keq), favoring the generation of MG, versus MGOH without organic additives. A simple way has been developed to stabilize the apparent Kd of MGA-MG binding over 24h, which may be beneficial in stabilizing other triphenylmethane or carbocation ligand-aptamer interactions that are susceptible to SN1 hydrolysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular recognition of malachite green by hemoglobin and their specific interactions: insights from in silico docking and molecular spectroscopy.

Science.gov (United States)

Peng, Wei; Ding, Fei; Peng, Yu-Kui; Sun, Ying

2014-01-01

Malachite green is an organic compound that can be widely used as a dyestuff for various materials; it has also emerged as a controversial agent in aquaculture. Since malachite green is proven to be carcinogenic and mutagenic, it may become a hazard to public health. For this reason, it is urgently required to analyze this controversial dye in more detail. In our current research, the interaction between malachite green and hemoglobin under physiological conditions was investigated by the methods of molecular modeling, fluorescence spectroscopy, circular dichroism (CD) as well as hydrophobic ANS displacement experiments. From the molecular docking, the central cavity of hemoglobin was assigned to possess high-affinity for malachite green, this result was corroborated by time-resolved fluorescence and hydrophobic ANS probe results. The recognition mechanism was found to be of static type, or rather the hemoglobin-malachite green complex formation occurred via noncovalent interactions such as π-π interactions, hydrogen bonds and hydrophobic interactions with an association constant of 10(4) M(-1). Moreover, the results also show that the spatial structure of the biopolymer was changed in the presence of malachite green with a decrease of the α-helix and increase of the β-sheet, turn and random coil suggesting protein damage, as derived from far-UV CD and three-dimensional fluorescence. Results of this work will help to further comprehend the molecular recognition of malachite green by the receptor protein and the possible toxicological profiles of other compounds, which are the metabolites and ramifications of malachite green.

Investigation on the interaction between an antimicrobial in aquaculture, malachite green and hemocyanin from mud crab Scylla paramamosain.

Science.gov (United States)

Li, Zhenxing; Tang, Boping; Zhang, Hongmei

2015-01-25

Interaction between malachite green and hemocyanin of crab plays a crucial role in the metabolism, distribution, and efficacy of toxic dyes in aquaculture. The mechanism of interaction between malachite green and Hc from mud crab was studied by using multi-spectral methods and molecular modeling in this work. The spectroscopic and thermodynamic data show that the interaction is a spontaneous process with the estimated enthalpy and entropy changes of -14.85(±1.86) kJ mol(-1) and 30.38(±5.21) J mol(-1) K(-1), respectively. The binding sites of malachite green in hemocyanin mainly locate in the interface of protein. The hydrophobic and electrostatic forces are the primary contributors to the interaction between hemocyanin and malachite green. The results of ultraviolet-vis absorbance, circular dichroism, and synchronous fluorescence spectroscopy suggest that the binding of malachite green to hemocyanin induces some conformational changes of protein. Copyright © 2014 Elsevier B.V. All rights reserved.

Permanent draft genome of the malachite-green-tolerant bacterium Rhizobium sp. MGL06.

Science.gov (United States)

Liu, Yang; Wang, Runping; Zeng, Runying

2014-12-01

Rhizobium sp. MGL06, the first Rhizobium isolate from a marine environment, is a malachite-green-tolerant bacterium with a broader salinity tolerance (range: 0.5% to 9%) than other rhizobia. This study sequences and annotates the draft genome sequence of this strain. Genome sequence information provides a basis for analyzing the malachite green tolerance, broad salinity adaptation, nitrogen fixation properties, and taxonomic classification of the isolate. Copyright © 2014 Elsevier B.V. All rights reserved.

Review of Methods for the Detection and Determination of Malachite Green and Leuco-Malachite Green in Aquaculture.

Science.gov (United States)

Zhou, Xinhui; Zhang, Jiaran; Pan, Zhongli; Li, Daoliang

2018-05-14

Malachite green (MG) has been widely used in the aquaculture industry as a fungicide and parasiticide because of its high efficiency and low cost, and it is commonly found in aquatic products and environmental water. However, MG and its primary metabolite, leuco-malachite green (LMG), are also toxic inorganic contaminants that are hazardous to the health of humans and other organisms. A variety of methods have been proposed in recent years for detecting and monitoring MG and LMG. This article was compiled as a general review of the methods proposed for MG and LMG detection, and several important detection parameters, such as the limit of detection, recovery and relative standard deviation, were tabulated. The analytical methods for the determination of MG and LMG in various matrices include high-performance liquid chromatography separation-based methods, liquid chromatography tandem mass spectrometry, surface-enhanced Raman spectroscopy, electrochemical methods, immunological assays, spectrophotometry and fluorescent methods which were described in detail in this article. In addition, some sample preparation techniques were also described. This review can provide expert guidance to the reader on the advantages, disadvantages and applicability of the different methodologies. This review also discussed challenges and several perspectives on the future trends in the determination of MG and LMG.

Adsorption of malachite green dye from aqueous solution on the bamboo leaf ash

Science.gov (United States)

Kuntari, Priwidyanjati, Dessyntha Anggiani

2017-12-01

Bamboo leaf ash has been developed as an adsorbent material for removal malachite green from aqueous solution. Adsorption parameters have studied are contact time and initial pH. The effect of contact time and pH were examined in the batch adsorption processes. The physicochemical characters of bamboo leaf ash were investigated by using X-Ray Diffraction (XRD) and FT-IR spectroscopy. Malachite green concentration was determined by UV-Vis spectrophotometer. FT-IR spectrogram of bamboo leaf ash shows that typical fingerprint of adsorbent material with Si-O-Si or Al-O-Al group. The X-ray diffractograms of bamboo leaf ash show that adsorbent material has a highly amorphous nature. The percentage of adsorption was showed raised with increasing contact time. The optimum removal of malachite green when the initial dye concentration, initial pH, weight of adsorbent and contact time was 20 mg/L, 7, 0.25 g and 75 minutes respectively.

Adsorption of Malachite Green Dye by Acid Activated Carbon - Kinetic, Thermodynamic and Equilibrium Studies

Directory of Open Access Journals (Sweden)

P. K. Baskaran

2011-01-01

Full Text Available The ability of zea mays dust carbon to remove malachite green from aqueous solutions has been studied for different adsorbate concentrations by varying the amount of adsorbent, temperature, pH and shaking time. Thermodynamic parameters such as ΔH°,ΔS° and ΔG°, were calculated from the slope and intercept of the linear plots. Analysis of adsorption results obtained at 303, 313, 323 and 333 K showed that the adsorption pattern on zea mays dust carbon seems to follow the Langmuir and Freundlich. The numerical values of sorption free energy indicate physical adsorption. The kinetic data indicated an intra-particle diffusion process with sorption being first order. The concentration of malachite green oxalate was measured before and after adsorption by using UV-visible spectrophotometer.

Adsorption of malachite green onto carbon prepared from borassus bar

International Nuclear Information System (INIS)

Arivoli, S; Hema, M; Prasath, P Martin Deva

2009-01-01

An activated carbon prepared from Borassus bark, a low-cost source, by sulphuric acid activation, was tested for its ability to remove malachite green in aqueous solution. The parameters studied included contact time, initial dye concentration, carbon dose, pH, and temperature. The adsorption followed first order rate equation and the rate was mainly controlled by intra-particle diffusion. Freundlich and Langmuir isotherm models were applied to the equilibrium data. The adsorption capacities (Qm) obtained from the Langmuir isotherm plots were 20.70, 20.25, 19.76, and 19.34 mg/g at 30, 40, 50, and 60 degree C, respectively, at an initial pH of 6.0. The temperature variation study showed that the malachite green adsorption was endothermic and spontaneous with increased randomness at the solid solution interface. (author)

TSDC and X-ray diffraction analysis of pure and malachite green sensitized polyvinyl carbazole films

International Nuclear Information System (INIS)

Mishra, Pankaj Kumar; Kathal, Rachana; Mishra, Jyoti; Pandey, Hariom; Khare, P. K.

2013-01-01

This paper describes the method for investigating the electrical properties of high solids via the study of thermal relaxation effects and offers an alternative scheme to the conventional bridge methods or the current voltage temperature measurements. For standard TSD experiment, this is comparable to a dielectric loss measurement, the low equivalent frequency and high sensitivity (ability to detect dipole concentration). The activation energies found by initial rise method are 0.31 ± 0.02 eV for pure and 0.43 ± 0.03 eV for malachite green sensitized PVK thermoelectrets. The peak current charges and activation energy associated with the peaks are affected by concentration of malachite green and have been explained in terms of formation of charge transfer complexes and molecular aggregates. The microscopic origin of a given current spectrum is explained by comparing the predictions of the general theories regarding the main polarization processes with the experimental data.

Rapid analysis of malachite green and leucomalachite green in fish muscles with surface-enhanced resonance Raman scattering.

Science.gov (United States)

Zhang, Yuanyuan; Yu, Wansong; Pei, Lu; Lai, Keqiang; Rasco, Barbara A; Huang, Yiqun

2015-02-15

Surface-enhanced resonance Raman scattering (SERRS) coupled with gold nanospheres was applied for rapid analysis of the hazardous substances malachite green (MG) and leucomalachite green (LMG) in fish muscle tissues. The lowest concentration of MG that could be detected was 0.5ngmL(-1) with high linear correlation (R(2)=0.970-0.998) between MG concentration and intensities of characteristic Raman peaks. A simplified sample preparation method taking less than 1h for recovering MG and LMG in fish fillets was developed for SERRS analysis, and 4-8 samples could be handled in parallel. MG and LMG could be detected in extracts of tilapia fish fillets at as low as 2ngg(-1) with SERRS and a simple principle component analysis method. For six other fish species, the lowest detectable concentration of MG ranged from 1ngg(-1) to 10ngg(-1). This study provides a new sensitive approach for the detection of trace amounts of the prohibited drugs MG and LMG in muscle food, which has the potential for rapidly screening a large number of samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

Improved removal of malachite green from aqueous solution using chemically modified cellulose by anhydride.

Science.gov (United States)

Zhou, Yanmei; Min, Yinghao; Qiao, Han; Huang, Qi; Wang, Enze; Ma, Tongsen

2015-03-01

Cellulose modified with maleic (M) and phthalic (P) anhydride, to be named CMA and CPA, were tested as feasible adsorbents for the removal of malachite green from aqueous solution. At the same time, the uptake ability of natural cellulose was also studied for comparison. The structure of material was characterized by FT-IR and XRD. The effects of solution pH, initial dye concentration, contact time and temperature were investigated in detail by batch adsorption experiments. The kinetic and isotherm studies suggested that the adsorption followed the pseudo-second-order model and Langmuir isotherm. The maximum adsorption capacity on CMA and CPA were 370 mg g(-1) and 111 mg g(-1), respectively. Furthermore, the thermodynamics studies indicated the spontaneous nature of adsorption of malachite green on adsorbents. All the studied results showed that the modified cellulose could be used as effective adsorption material for the removal of malachite green from aqueous solutions. Copyright © 2014 Elsevier B.V. All rights reserved.

Colorimetric Detection of Multidrug-Resistant or Extensively Drug-Resistant Tuberculosis by Use of Malachite Green Indicator Dye▿

OpenAIRE

Farnia, Parissa; Masjedi, Mohammad Reza; Mohammadi, Foroozan; Tabarsei, Payam; Farnia, Poopak; Mohammadzadeh, Ali Reza; Baghei, Parvaneh; Varahram, Mohammad; Hoffner, Sven; Velayati, Ali Akbar

2007-01-01

The malachite green microtube (MGMT) susceptibility assay was performed directly on sputum specimens (n = 80) and indirectly on Mycobacterium tuberculosis clinical isolates (n = 60). The technique is based on the malachite green dye, which changes color in response to M. tuberculosis growth. The MGMT assay is simple and rapid and does not require expensive instruments.

Temperature sensitive molecularly imprinted microspheres for solid-phase dispersion extraction of malachite green, crystal violet and their leuko metabolites

International Nuclear Information System (INIS)

Tan, Lei; Chen, Kuncai; He, Rong; Peng, Rongfei; Huang, Cong

2016-01-01

This article demonstrates the feasibility of an alternative strategy for producing temperature sensitive molecularly imprinted microspheres (MIMs) for solid-phase dispersion extraction of malachite green, crystal violet and their leuko metabolites. Thermo-sensitive MIMs can change their structure following temperature stimulation. This allows capture and release of target molecules to be controlled by temperature. The fabrication technique provides surface molecular imprinting in acetonitrile using vinyl modified silica microspheres as solid supports, methacrylic acid and N-isopropyl acrylamide as the functional monomers, ethyleneglycol dimethacrylate as the cross-linker, and malachite green as the template. After elution of the template, the MIMs can be used for fairly group-selective solid phase dispersion extraction of malachite green, crystal violet, leucomalachite green, and leucocrystal violet from homogenized fish samples at a certain temperature. Following centrifugal separation of the microspheres, the analytes were eluted with a 95:5 mixture of acetonitrile and formic acid, and then quantified by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) with isotope internal calibration. The detection limits for malachite green, crystal violet and their metabolites typically are 30 ng·kg −1 . Positive samples were identified by UHPLC-MS/MS in the positive ionization mode with multiple reaction monitoring. The method was applied to the determination of the dyes and the respective leuko dyes in fish samples, and accuracy and precision were validated by comparative analysis of the samples by using aluminum neutral columns. (author)

Quantitative Detection of Trace Malachite Green in Aquiculture Water Samples by Extractive Electrospray Ionization Mass Spectrometry.

Science.gov (United States)

Fang, Xiaowei; Yang, Shuiping; Chingin, Konstantin; Zhu, Liang; Zhang, Xinglei; Zhou, Zhiquan; Zhao, Zhanfeng

2016-08-11

Exposure to malachite green (MG) may pose great health risks to humans; thus, it is of prime importance to develop fast and robust methods to quantitatively screen the presence of malachite green in water. Herein the application of extractive electrospray ionization mass spectrometry (EESI-MS) has been extended to the trace detection of MG within lake water and aquiculture water, due to the intensive use of MG as a biocide in fisheries. This method has the advantage of obviating offline liquid-liquid extraction or tedious matrix separation prior to the measurement of malachite green in native aqueous medium. The experimental results indicate that the extrapolated detection limit for MG was ~3.8 μg·L(-1) (S/N = 3) in lake water samples and ~0.5 μg·L(-1) in ultrapure water under optimized experimental conditions. The signal intensity of MG showed good linearity over the concentration range of 10-1000 μg·L(-1). Measurement of practical water samples fortified with MG at 0.01, 0.1 and 1.0 mg·L(-1) gave a good validation of the established calibration curve. The average recoveries and relative standard deviation (RSD) of malachite green in lake water and Carassius carassius fish farm effluent water were 115% (6.64% RSD), 85.4% (9.17% RSD) and 96.0% (7.44% RSD), respectively. Overall, the established EESI-MS/MS method has been demonstrated suitable for sensitive and rapid (malachite green in various aqueous media, indicating its potential for online real-time monitoring of real life samples.

Photodegradation of malachite green under simulated and natural irradiation: Kinetics, products, and pathways

International Nuclear Information System (INIS)

Yong, Li; Zhanqi, Gao; Yuefei, Ji; Xiaobin, Hu; Cheng, Sun; Shaogui, Yang; Lianhong, Wang; Qingeng, Wang; Die, Fang

2015-01-01

Highlights: • Photofate of malachite green was studied under simulated and natural irradiation. • Favorable conditions for degradation were optimized by the orthogonal array design. • Main ROS for the decomposition were determined by free radical quenchers. • Fifty-three products were determined by LC–MS and GC–MS. • Pathways were proposed with the aid of theoretical calculation. - Abstract: In this work photodegradation rates and pathways of malachite green were studied under simulated and solar irradiation with the goal of assessing the potential of photolysis as a removal mechanism in real aquatic environment. Factors influencing the photodegradation process were investigated, including pH, humic acid, Fe 2+ , Ca 2+ , HCO 3 − , and NO 3 − , of which favorable conditions were optimized by the orthogonal array design under simulated sunlight irradiation in the presence of dissolved oxygen. The degradation processes of malachite green conformed to pseudo first-order kinetics and their degradation rate constants were between 0.0062 and 0.4012 h −1 . Under solar irradiation, the decolorization efficiency of most tests can reach almost 100%, and relatively thorough mineralization could be observed. Forty degradation products were detected by liquid chromatography–mass spectrometry, and thirteen small molecular products were identified by gas chromatography–mass spectrometry. Based on the analyses of the degradation products and calculation of the frontier electron density, the pathways were proposed: decomposition of conjugated structure, N-demethylation reactions, hydroxyl addition reactions, the removal of benzene ring, and the ring-opening reaction. This study has provided a reference, both for photodegradation of malachite green and future safety applications and predictions of decontamination of related triphenylmethane dyes under real conditions

Fluorinated Analogs of Malachite Green: Synthesis and Toxicity

Directory of Open Access Journals (Sweden)

Bahram Parvin

2008-04-01

Full Text Available A series of fluorinated analogs of malachite green (MG have been synthesizedand their toxicity to Saccharomyces cerevisiae and a human ovarian epithelial cell lineexamined. The toxicity profiles were found to be different for these two species. Twoanalogs, one with 2,4-difluoro substitution and the other with 2-fluoro substitution seem tobe the most promising analogs because they showed the lowest toxicity to the human cells.

Fluorinated analogs of malachite green: synthesis and toxicity.

Science.gov (United States)

Kraus, George A; Jeon, Insik; Nilsen-Hamilton, Marit; Awad, Ahmed M; Banerjee, Jayeeta; Parvin, Bahram

2008-04-27

A series of fluorinated analogs of malachite green (MG) have been synthesized and their toxicity to Saccharomyces cerevisiae and a human ovarian epithelial cell line examined. The toxicity profiles were found to be different for these two species. Two analogs, one with 2,4-difluoro substitution and the other with 2-fluoro substitution seem to be the most promising analogs because they showed the lowest toxicity to the human cells.

Photodegradation of malachite green under simulated and natural irradiation: Kinetics, products, and pathways

Energy Technology Data Exchange (ETDEWEB)

Yong, Li [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Zhanqi, Gao [State Environmental Protection Key Laboratory of Monitoring and Analysis for Organic Pollutants in Surface Water, Jiangsu Provincial Environmental Monitoring Center, Nanjing 210036 (China); Yuefei, Ji [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Xiaobin, Hu [School of Life Science, Huzhou University, Huzhou 313000 (China); Cheng, Sun, E-mail: envidean@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Shaogui, Yang; Lianhong, Wang; Qingeng, Wang; Die, Fang [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China)

2015-03-21

Highlights: • Photofate of malachite green was studied under simulated and natural irradiation. • Favorable conditions for degradation were optimized by the orthogonal array design. • Main ROS for the decomposition were determined by free radical quenchers. • Fifty-three products were determined by LC–MS and GC–MS. • Pathways were proposed with the aid of theoretical calculation. - Abstract: In this work photodegradation rates and pathways of malachite green were studied under simulated and solar irradiation with the goal of assessing the potential of photolysis as a removal mechanism in real aquatic environment. Factors influencing the photodegradation process were investigated, including pH, humic acid, Fe{sup 2+}, Ca{sup 2+}, HCO{sub 3}{sup −}, and NO{sub 3}{sup −}, of which favorable conditions were optimized by the orthogonal array design under simulated sunlight irradiation in the presence of dissolved oxygen. The degradation processes of malachite green conformed to pseudo first-order kinetics and their degradation rate constants were between 0.0062 and 0.4012 h{sup −1}. Under solar irradiation, the decolorization efficiency of most tests can reach almost 100%, and relatively thorough mineralization could be observed. Forty degradation products were detected by liquid chromatography–mass spectrometry, and thirteen small molecular products were identified by gas chromatography–mass spectrometry. Based on the analyses of the degradation products and calculation of the frontier electron density, the pathways were proposed: decomposition of conjugated structure, N-demethylation reactions, hydroxyl addition reactions, the removal of benzene ring, and the ring-opening reaction. This study has provided a reference, both for photodegradation of malachite green and future safety applications and predictions of decontamination of related triphenylmethane dyes under real conditions.

Formation of an intermediate radical cation in the nanosecond pulse radiolysis of malachite green leucocyanide in organic solvents

International Nuclear Information System (INIS)

Grodkowski, J.; Bobrowski, K.; Mehnert, R.; Brede, O.

1989-01-01

The malachite green leucocyanide (MGCN) was irradiated in argon or oxygen saturated solutions of n-butyl chloride, 1.2-DCE, CCl 4 and acetone with 13 ns electron pulses. Two species with absorption maxima at 620 and 480 nm were observed. The latter was attributed to the malachite green leucocyanide radical cation (MGCN +radical ) and the former to the known carbonium ion of malachite green dye (MG + ). Observation of the consecutive charge transfer via the schemes: DCE +radical → BPh +radical → MGCN +radical and DCE +radical → MGCN +radical → TMPD +radical , allowed to estimate the ionization potential of MGCN molecule in the range 6.9 eV MGCN +radical radical cation is located in the ''aniline'' part of the molecule. (author)

Novel Castellaniella denitrificans SA13P as a Potent Malachite Green Decolorizing Strain

Directory of Open Access Journals (Sweden)

Ankita Chawla

2014-01-01

Full Text Available Triphenylmethane dyes represent a major group of dyes causing serious environmental hazards. Malachite Green is one of the commonly and extensively used triphenylmethane dyes although it is carcinogenic and mutagenic in nature. Various physicochemical methods have been employed for its elimination but are highly expensive, coupled with the formation of huge amount of sludge. Hence, biological methods being ecofriendly are good alternatives. In the present study, the novel bacterial isolate SA13P was isolated from UASB tank of tannery effluent treatment plant. Phylogenetic characterization of 1470 bp fragment of SA13P has revealed its similarity with Castellaniella denitrificans. This strain has been found to decolorize the dye (malachite green at a concentration of 100 mg L−1 (80.29%. Decolorization was done by living bacterial cells rather than adsorption. Growth conditions have also been optimized for the decolorization. Maximum decolorization was observed at a temperature of 37°C and pH 8.0. Also, it has been found that bacterization of seeds of Vigna radiata with Castellaniella denitrificans SA13P increases germination rate. We have reported for the first time that Castellaniella denitrificans SA13P may be used as a novel strain for dye decolorization (malachite green and biological treatment of tannery effluent.

Removal of Malachite Green Dye from Aqueous Solution Using Multi-Walled Carbon Nano tubes: An Application of Experimental Design

International Nuclear Information System (INIS)

Siti Aminah Zulkepli; Md Pauzi Abdullah; Md Pauzi Abdullah; Wan Mohd Afiq Wan Mohd Khalik

2016-01-01

An experimental design methodology was performed in the optimization of removal of malachite green dye by multi-walled carbon nano tubes. A Central Composite Design (25) was chosen to develop a mathematical model and determine the optimum condition for adsorption of malachite green by carbon nano tubes. Five experimental factors, namely initial dye concentration, mass of adsorbent, pH, contact time and agitation speed were studied. Maximum adsorption of malachite green was achieved at the suggested optimum conditions: initial dye concentration (20 ppm), weight of adsorbent (0.03 g), pH solution (7) contact time (17 min) and agitation speed (150 strokes per min). The experimental value of adsorption by multi-walled carbon nano tubes were found to be in good agreement with the predicted value (R"2 = 0.922).The experimental equilibrium data were best fitted to isotherm model (Langmuir) and kinetic model (pseudo second-order) respectively. Maximum adsorption by carbon nano tubes at monolayer for malachite green was obtained at 112.36 mg/ g while kinetic rate constant was calculated to be 0.0017 g mg"-"1 min"-"1. (author)

Isolation of nontuberculous mycobacteria from soil using Middlebrook 7H10 agar with increased malachite green concentration.

Science.gov (United States)

Hu, Yuli; Yu, Xinglong; Zhao, Dun; Li, Runcheng; Liu, Yang; Ge, Meng; Hu, Huican

2017-12-01

Environmental exposure is considered to be responsible for nontuberculous mycobacterial infections in humans. To facilitate the isolation of mycobacteria from soil, Middlebrook 7H10 agar was optimized as an enhanced selective medium by increasing the concentration of malachite green. A series of modified Middlebrook 7H10 agar media with malachite green concentrations ranging from 2.5 to 2500 mg/L was evaluated using 20 soil samples decontaminated with 3% sodium dodecyl sulfate plus 2% NaOH for 30 min. Among these modified Middlebrook 7H10 media, the medium with malachite green at a concentration of 250 mg/L, i.e., at the same concentration as in Löwenstein-Jensen medium, was the most effective in terms of the number of plates with mycobacterial growth. This medium was further evaluated with 116 soil samples. The results showed that 87.1% (101/116) of the samples produced mycobacterial growth, and 15 samples (12.9%) produced no mycobacterial growth. Of the plates inoculated with the soil samples, each in duplicate, 5.2% (12/232) showed late contamination. In total, 19 mycobacterial species were isolated, including seven (36.8%) rapidly growing mycobacteria and 12 (63.2%) slowly growing mycobacteria. Our results demonstrate that the modified Middlebrook 7H10 agar with 250 mg/L malachite green is useful for the primary isolation of nontuberculous mycobacteria from soil.

Photodegradation of malachite green under simulated and natural irradiation: kinetics, products, and pathways.

Science.gov (United States)

Yong, Li; Zhanqi, Gao; Yuefei, Ji; Xiaobin, Hu; Cheng, Sun; Shaogui, Yang; Lianhong, Wang; Qingeng, Wang; Die, Fang

2015-03-21

In this work photodegradation rates and pathways of malachite green were studied under simulated and solar irradiation with the goal of assessing the potential of photolysis as a removal mechanism in real aquatic environment. Factors influencing the photodegradation process were investigated, including pH, humic acid, Fe(2+), Ca(2+), HCO3(-), and NO3(-), of which favorable conditions were optimized by the orthogonal array design under simulated sunlight irradiation in the presence of dissolved oxygen. The degradation processes of malachite green conformed to pseudo first-order kinetics and their degradation rate constants were between 0.0062 and 0.4012 h(-1). Under solar irradiation, the decolorization efficiency of most tests can reach almost 100%, and relatively thorough mineralization could be observed. Forty degradation products were detected by liquid chromatography-mass spectrometry, and thirteen small molecular products were identified by gas chromatography-mass spectrometry. Based on the analyses of the degradation products and calculation of the frontier electron density, the pathways were proposed: decomposition of conjugated structure, N-demethylation reactions, hydroxyl addition reactions, the removal of benzene ring, and the ring-opening reaction. This study has provided a reference, both for photodegradation of malachite green and future safety applications and predictions of decontamination of related triphenylmethane dyes under real conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Lipoprotein Processing Is Essential for Resistance of Mycobacterium tuberculosis to Malachite Green▿

Science.gov (United States)

Banaei, Niaz; Kincaid, Eleanor Z.; Lin, S.-Y. Grace; Desmond, Edward; Jacobs, William R.; Ernst, Joel D.

2009-01-01

Malachite green, a synthetic antimicrobial dye, has been used for over 50 years in mycobacterial culture medium to inhibit the growth of contaminants. The molecular basis of mycobacterial resistance to malachite green is unknown, although the presence of malachite green-reducing enzymes in the cell envelope has been suggested. The objective of this study was to investigate the role of lipoproteins in resistance of Mycobacterium tuberculosis to malachite green. The replication of an M. tuberculosis lipoprotein signal peptidase II (lspA) mutant (ΔlspA::lspAmut) on Middlebrook agar with and without 1 mg/liter malachite green was investigated. The lspA mutant was also compared with wild-type M. tuberculosis in the decolorization rate of malachite green and sensitivity to sodium dodecyl sulfate (SDS) detergent and first-line antituberculosis drugs. The lspA mutant has a 104-fold reduction in CFU-forming efficiency on Middlebrook agar with malachite green. Malachite green is decolorized faster in the presence of the lspA mutant than wild-type bacteria. The lspA mutant is hypersensitive to SDS detergent and shows increased sensitivity to first-line antituberculosis drugs. In summary, lipoprotein processing by LspA is essential for resistance of M. tuberculosis to malachite green. A cell wall permeability defect is likely responsible for the hypersensitivity of lspA mutant to malachite green. PMID:19596883

Solvent extraction of W(VI) and Hg(II) with malachite green and rhodamine-B respectively into organic solvents

International Nuclear Information System (INIS)

Patil, V.B.; David, M.M.; Turel, Z.R.

1992-01-01

Aqueous malachite green and alcoholic rhodamine-B have been used for the extraction of tungsten( W(VI)) and mercury( Hg(II)) respectively into nitrobenzene. This paper deals with developing a rapid method and selective method for the extraction of tungsten(W(VI)) and mercury (Hg(II)) using malachite green and rhodamine-B respectively. 185 W and 203 Hg were used as tracers for studying the extraction process.(author). 2 refs., 2 tab

Photodynamic inactivation of Staphylococcus aureus and Escherichia coli biofilms by malachite green and phenothiazine dyes: an in vitro study.

Science.gov (United States)

Vilela, Simone Furgeri Godinho; Junqueira, Juliana Campos; Barbosa, Junia Oliveira; Majewski, Marta; Munin, Egberto; Jorge, Antonio Olavo Cardoso

2012-06-01

The organization of biofilms in the oral cavity gives them added resistance to antimicrobial agents. The action of phenothiazinic photosensitizers on oral biofilms has already been reported. However, the action of the malachite green photosensitizer upon biofilm-organized microorganisms has not been described. The objective of the present work was to compare the action of malachite green with the phenothiazinic photosensitizers (methylene blue and toluidine blue) on Staphylococcus aureus and Escherichia coli biofilms. The biofilms were grown on sample pieces of acrylic resin and subjected to photodynamic therapy using a 660-nm diode laser and photosensitizer concentrations ranging from 37.5 to 3000 μM. After photodynamic therapy, cells from the biofilms were dispersed in a homogenizer and cultured in Brain Heart Infusion broth for quantification of colony-forming units per experimental protocol. For each tested microorganism, two control groups were maintained: one exposed to the laser radiation without the photosensitizer (L+PS-) and other treated with the photosensitizer without exposure to the red laser light (L-PS+). The results were subjected to descriptive statistical analysis. The best results for S. aureus and E. coli biofilms were obtained with photosensitizer concentrations of approximately 300 μM methylene blue, with microbial reductions of 0.8-1.0 log(10); 150 μM toluidine blue, with microbial reductions of 0.9-1.0 log(10); and 3000 μM malachite green, with microbial reductions of 1.6-4.0 log(10). Greater microbial reduction was achieved with the malachite green photosensitizer when used at higher concentrations than those employed for the phenothiazinic dyes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Formation of an intermediate radical cation in the nanosecond pulse radiolysis of malachite green leucocyanide in organic solvents

Energy Technology Data Exchange (ETDEWEB)

Grodkowski, J; Bobrowski, K; Mehnert, R; Brede, O

1989-01-01

The malachite green leucocyanide (MGCN) was irradiated in argon or oxygen saturated solutions of n-butyl chloride, 1.2-DCE, CCl/sub 4/ and acetone with 13 ns electron pulses. Two species with absorption maxima at 620 and 480 nm were observed. The latter was attributed to the malachite green leucocyanide radical cation (MGCN/sup +radical/) and the former to the known carbonium ion of malachite green dye (MG/sup +/). Observation of the consecutive charge transfer via the schemes: DCE/sup +radical/ -> BPh/sup +radical/ -> MGCN/sup +radical/ and DCE/sup +radical/ -> MGCN/sup +radical/ -> TMPD/sup +radical/, allowed to estimate the ionization potential of MGCN molecule in the range 6.9 eV < Ip/sub MGCN/ < 8.27 eV. Presented results and literature data suggest that positive charge in MGCN/sup +radical/ radical cation is located in the ''aniline'' part of the molecule. (author).

Extraction-absorptiometric determination of copper by malachite green in natural and waste waters

International Nuclear Information System (INIS)

Arstamyan, Zh.M.; Mangasaryan, S.H.

2006-01-01

In interaction of Cu anionic complex with three phenylmethane basic dye-malachite green has been studied. The colored ionic associate could be extracted by benzene in 1.0 M hydrochloric acid solution. The method is based on the reduction of Cu(II) to Cu(I) with ascorbic acid.The calibration graph obeyed Beer's law over the range 0,125-10,0 m kg/ml copper. The apparent molar absorptivity of the extract was 8,7·10 4± 500 l mol - 1 c m 1 . The molar ratio between Cu(I) chloride complex and cation of malachite green in ionic associate has been determined by method Asmuse which is (1:1). The influence of foreign ions on the determination of copper has been studied. Methods was applied for determination of cooper in natural and waste waters

Determination of residues of three triphenylmethane dyes and their metabolites (malachite green, leuco malachite green, crystal violet, leuco crystal violet, and brilliant green) in aquaculture products by LC/MS/MS: first action 2012.25.

Science.gov (United States)

Hurtaud-Pessel, Dominique; Couëdor, Pierrick; Verdon, Eric; Dowell, Dawn

2013-01-01

During the AOAC Annual Meeting held from September 30 to October 3, 2012 in Las Vegas, NV, the Expert Review Panel (ERP) on Veterinary Drug Residues reviewed data for the method for determination of residues of three triphenylmethane dyes and their metabolites (malachite green, leuco malachite green, crystal violet, leuco crystal violet, and brilliant green) in aquaculture products by LC/MS/MS, previously published in the Journal of Chromatography A 1218, 1632-1645 (2006). The method data were reviewed and compared to the standard method performance requirements (SMPRs) found in SMPR 2009.001, published in AOAC's Official Methods of Analysis, 19th Ed. (2012). The ERP determined that the data were acceptable, and the method was approved AOAC Official First Action. The method uses acetonitrile to isolate the analyte from the matrix. Then determination is conducted by LCIMS/MS with positive electrospray ionization. Accuracy ranged from 100.1 to 109.8% for samples fortified at levels of 0.5, 0.75, 1.0, and 2.0 microg/kg. Precision ranged from 2.0 to 10.3% RSD for the intraday samples and 1.9 to 10.6% for the interday samples analyzed over 3 days. The described method is designed to accurately operate in the analytical range from 0.5 to 2 microg/kg, where the minimum required performance limit for laboratories has been fixed in the European Union at 2.0 microg/kg for these banned substances and their metabolites. Upper levels of concentrations (1-100 microg/kg) can be analyzed depending on the different optional calibrations used.

Removal of Pb(II ions and malachite green dye from wastewater by activated carbon produced from lemon peel

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Sayed Zia Mohammadi

2014-06-01

Full Text Available In the present study, a high-surface area activated carbon was prepared by chemical activation of lemon peel with H3PO4 as the active agent. Then, the adsorption behavior of Malachite green dye and Pb(II ions on the produced activated carbon was studied. Batch process was employed for sorption kinetics and equilibrium studies. Experimental data were �tted to various isotherm models. According to the Langmuir model, the maximum adsorption capacities of Malachite green dye and Pb(II ions were found to be 66.67 and 90.91 mg g-1, respectively, at room temperature. Kinetic studies showed the adsorption process followed a pseudo second-order rate model. The sorption kinetics were controlled by intra-particle diffusion. The results indicated that the produced activated carbon can be economically and effectively used as an adsorbent for the removal of Malachite green dye and Pb(II ions from wastewaters.

Fast and sensitive trace analysis of malachite green using a surface-enhanced Raman microfluidic sensor.

Science.gov (United States)

Lee, Sangyeop; Choi, Junghyun; Chen, Lingxin; Park, Byungchoon; Kyong, Jin Burm; Seong, Gi Hun; Choo, Jaebum; Lee, Yeonjung; Shin, Kyung-Hoon; Lee, Eun Kyu; Joo, Sang-Woo; Lee, Kyeong-Hee

2007-05-08

A rapid and highly sensitive trace analysis technique for determining malachite green (MG) in a polydimethylsiloxane (PDMS) microfluidic sensor was investigated using surface-enhanced Raman spectroscopy (SERS). A zigzag-shaped PDMS microfluidic channel was fabricated for efficient mixing between MG analytes and aggregated silver colloids. Under the optimal condition of flow velocity, MG molecules were effectively adsorbed onto silver nanoparticles while flowing along the upper and lower zigzag-shaped PDMS channel. A quantitative analysis of MG was performed based on the measured peak height at 1615 cm(-1) in its SERS spectrum. The limit of detection, using the SERS microfluidic sensor, was found to be below the 1-2 ppb level and this low detection limit is comparable to the result of the LC-Mass detection method. In the present study, we introduce a new conceptual detection technology, using a SERS microfluidic sensor, for the highly sensitive trace analysis of MG in water.

Lipoprotein Processing Is Essential for Resistance of Mycobacterium tuberculosis to Malachite Green▿

OpenAIRE

Banaei, Niaz; Kincaid, Eleanor Z.; Lin, S.-Y. Grace; Desmond, Edward; Jacobs, William R.; Ernst, Joel D.

2009-01-01

Malachite green, a synthetic antimicrobial dye, has been used for over 50 years in mycobacterial culture medium to inhibit the growth of contaminants. The molecular basis of mycobacterial resistance to malachite green is unknown, although the presence of malachite green-reducing enzymes in the cell envelope has been suggested. The objective of this study was to investigate the role of lipoproteins in resistance of Mycobacterium tuberculosis to malachite green. The replication of an M. tubercu...

Reduced toxicity of malachite green decolorized by laccase produced from Ganoderma sp. rckk-02 under solid-state fermentation.

Science.gov (United States)

Sharma, Abha; Shrivastava, Bhuvnesh; Kuhad, Ramesh Chander

2015-10-01

Statistical designs were applied for optimizing laccase production from a white-rot fungus, Ganoderma sp. rckk-02 under solid-state fermentation (SSF). Compared to unoptimized conditions [2,154 U/gds (Unit per gram of dry substrate)], the optimization process resulted in a 17.3-fold increase in laccase production (37,423 U/gds). The laccase produced was evaluated for its potential to decolorize a recalcitrant synthetic dye, malachite green. Laccase at dosage of 30 U/ml in presence of 1 mM of 1-hydroxybenzotriazole (HBT) almost completely decolorized 100 and 200 mg/l of malachite green in 16 and 20 h, respectively, at 30 °C, pH 5.5 and 150 rpm. While, higher dyes concentrations of 300, 400 and 500 mg/l were decolorized to 72, 62 and 55 % in 24, 28 and 32 h, respectively, under similar conditions. Furthermore, it was observed that the decolorized malachite green was less toxic towards the growth of five white-rot fungi tested viz. Crinipellis sp. RCK-1, Ganoderma sp. rckk-02, Coriolopsis Caperata RCK 2011, Phanerochaete chrysosporium K3 and Pycnoporous cinnabarinus PB. The present study demonstrates the potential of Ganoderma sp. rckk-02 to produce high titres of laccase under SSF, which can be exploited in conjunction with redox mediator for the decolorization of high concentrations of malachite green from water bodies.

Sensitive detection of malachite green and crystal violet by nonlinear laser wave mixing and capillary electrophoresis.

Science.gov (United States)

Maxwell, Eric J; Tong, William G

2016-05-01

An ultrasensitive label-free antibody-free detection method for malachite green and crystal violet is presented using nonlinear laser wave-mixing spectroscopy and capillary zone electrophoresis. Wave-mixing spectroscopy provides a sensitive absorption-based detection method for trace analytes. This is accomplished by forming dynamic gratings within a sample cell, which diffracts light to create a coherent laser-like signal beam with high optical efficiency and high signal-to-noise ratio. A cubic dependence on laser power and square dependence on analyte concentration make wave mixing sensitive enough to detect molecules in their native form without the use of fluorescent labels for signal enhancement. A 532 nm laser and a 635 nm laser were used for malachite green and crystal violet sample excitation. The use of two lasers of different wavelengths allows the method to simultaneously detect both analytes. Selectivity is obtained through the capillary zone electrophoresis separation, which results in characteristic migration times. Measurement in capillary zone electrophoresis resulted in a limit of detection of 6.9 × 10(-10)M (2.5 × 10(-19) mol) for crystal violet and 8.3 × 10(-11)M (3.0 × 10(-20) mol) for malachite green at S/N of 2. Copyright © 2016. Published by Elsevier B.V.

Optical properties of (nanometer MCM-41)-(malachite green) composite materials

International Nuclear Information System (INIS)

Li Xiaodong; Zhai Qingzhou; Zou Mingqiang

2010-01-01

Nanosized materials loaded with organic dyes are of interest with respect to novel optical applications. The optical properties of malachite green (MG) in MCM-41 are considerably influenced by the limited nanoporous channels of nanometer MCM-41. Nanometer MCM-41 was synthesized by tetraethyl orthosilicate (TEOS) as the source of silica and cetyltrimethylammonium bromide (CTMAB) as the template. The liquid-phase grafting method has been employed for incorporation of the malachite green molecules into the channels of nanometer MCM-41. A comparative study has been carried out on the adsorption of the malachite green into modified MCM-41 and unmodified MCM-41. The modified MCM-41 was synthesized using a silylation reagent, trimethychlorosilane (TMSCl), which functionalized the surface of nanometer MCM-41 for proper host-guest interaction. The prepared (nanometer MCM-41)-MG samples have been studied by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, low-temperature nitrogen adsorption-desorption technique at 77 K, Raman spectra and luminescence studies. In the prepared (nanometer MCM-41)-MG composite materials, the frameworks of the host molecular sieve were kept intact and the MG located inside the pores of MCM-41. Compared with the MG, it is found that the prepared composite materials perform a considerable luminescence. The excitation and emission spectra of MG in both modified MCM-41 and unmodified MCM-41 were examined to explore the structural effects on the optical properties of MG. The results of luminescence spectra indicated that the MG molecules existed in monomer form within MCM-41. However, the luminescent intensity of MG incorporated in the modified MCM-41 are higher than that of MG encapsulated in unmodified MCM-41, which may be due to the anchored methyl groups on the channels of the nanometer MCM-41 and the strong host-guest interactions. The steric effect from the pore size of the host materials is significant. Raman

Solvent extraction of Sb(III) with malachite green into chloroform

International Nuclear Information System (INIS)

Shanbhag, B.S.; Turel, Z.R.

2002-01-01

A rapid and selective method for the solvent extraction of Sb(III) using malachite green (C. I. Basic green 4) has been described. Effect of different parameters affecting the extraction coefficient value of Sb(III) such as acidity, time of equilibration, KI concentration, solvents, anions, etc. has been studied. For various elements the separation factor has been evaluated. The stoichiometry of the extracted species has been determined by the method of substoichiometric extraction. The decontamination factor for some elements using substoichiometric quantities of the extracting agent has been evaluated. Radiotracers were employed for the extraction studies. The method elaborated has been employed for the quantitative determination of antimony in normal, benign and cancerous tissues of the human brain. (author)

Spectrophotometric determination of boron by solvent extraction with 2-hydroxy-2-methylbutyric acid and malachite green

International Nuclear Information System (INIS)

Sato, Shigeya; Uchikawa, Sumio

1984-01-01

A very simple and sensitive method for the spectrophotometric determination of boron was developed. Boron was found to react with 2-hydroxy-2-methylbutyric acid in weak acidic aqueous solution at room temperature to form a complex anion which can be extracted into chlorobenzene with malachite green in a single extraction; boron is determined indirectly by measuring the absorbance of malachite green in the extract at 629 nm. The calibration graph is linear over the range (7.50 x 10 -7 - 2.00 x 10 -5 ) mol dm -3 boron; the apparent molar absorptivity is 6.50 x 10 4 dm 3 mol -1 cm -1 . The method is applied to the determination of micro amounts of boron in natural waters with satisfactory results. (author)

Function and dynamics of aptamers: A case study on the malachite green aptamer

Energy Technology Data Exchange (ETDEWEB)

Wang, Tianjiao [Iowa State Univ., Ames, IA (United States)

2008-01-01

Aptamers are short single-stranded nucleic acids that can bind to their targets with high specificity and high affinity. To study aptamer function and dynamics, the malachite green aptamer was chosen as a model. Malachite green (MG) bleaching, in which an OH- attacks the central carbon (C1) of MG, was inhibited in the presence of the malachite green aptamer (MGA). The inhibition of MG bleaching by MGA could be reversed by an antisense oligonucleotide (AS) complementary to the MGA binding pocket. Computational cavity analysis of the NMR structure of the MGA-MG complex predicted that the OH^- is sterically excluded from the C1 of MG. The prediction was confirmed experimentally using variants of the MGA with changes in the MG binding pocket. This work shows that molecular reactivity can be reversibly regulated by an aptamer-AS pair based on steric hindrance. In addition to demonstrate that aptamers could control molecular reactivity, aptamer dynamics was studied with a strategy combining molecular dynamics (MD) simulation and experimental verification. MD simulation predicted that the MG binding pocket of the MGA is largely pre-organized and that binding of MG involves reorganization of the pocket and a simultaneous twisting of the MGA terminal stems around the pocket. MD simulation also provided a 3D-structure model of unoccupied MGA that has not yet been obtained by biophysical measurements. These predictions were consistent with biochemical and biophysical measurements of the MGA-MG interaction including RNase I footprinting, melting curves, thermodynamic and kinetic constants measurement. This work shows that MD simulation can be used to extend our understanding of the dynamics of aptamer-target interaction which is not evident from static 3D-structures. To conclude, I have developed a novel concept to control molecular reactivity by an aptamer based on steric protection and a strategy to study the dynamics of aptamer-target interaction by combining MD

Solvent extraction of W(VI) with malachite green into nitrobenzene

International Nuclear Information System (INIS)

Patil, V.B.; Turel, Z.R.

1995-01-01

A rapid and selective method has been developed for the extraction of W(VI) with malachite green into nitrobenzene. The effect of various parameters on the extraction coefficient value such as effect of pH, time of equilibration, effect of various cations and anions have been evaluated. The stoichiometry of metal to reagent determined by the method of substoichiometric extraction was found to be 1:1. It was further supported by the slope ratio method. (author). 6 refs., 2 tabs., 2 figs

Solvent extraction of W(VI) with malachite green into nitrobenzene

Energy Technology Data Exchange (ETDEWEB)

Patil, V B; Turel, Z R [The Institute of Science, Bombay (India). Nuclear Chemistry Division

1995-04-01

A rapid and selective method has been developed for the extraction of W(VI) with malachite green into nitrobenzene. The effect of various parameters on the extraction coefficient value such as effect of pH, time of equilibration, effect of various cations and anions have been evaluated. The stoichiometry of metal to reagent determined by the method of substoichiometric extraction was found to be 1:1. It was further supported by the slope ratio method. (author). 6 refs., 2 tabs., 2 figs.

Biosorption Studies for the Removal of Malachite Green from its Aqueous Solution by Activated Carbon Prepared from Cassava Peel

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C. Parvathi

2011-01-01

Full Text Available The association of dyes with health related problems is not a new phenomenon. The effectiveness of carbon adsorption for dye removal from textile effluent has made it an ideal alternative to other expensive treatment methods. The preparation of activated carbon from agricultural waste could increase economic return and reduce pollution. Cassava peel has been used as a raw material to produce activated carbon. The study investigates the removal of malachite green dye from its aqueous solution. The effects of condition such as adsorbent dosage, initial dye concentration, pH and contact time were studied. The adsorption capacity was demonstrated as a function of time for malachite green from aqueous solution by the prepared activated carbon. The results showed that as the amount of the adsorbent was increased, the percentage of dye removal increased accordingly. Higher adsorption percentages were observed at lower concentrations of malachite green dye. Silver nitrate treated cassava peel showed a better performance compared to Sulphuric acid treated and raw carbons, thus making it an interesting option for dye removal textile effluent.

Utilization of unconventional lignocellulosic waste biomass for the biosorption of toxic triphenylmethane dye malachite green from aqueous solution.

Science.gov (United States)

Selvasembian, Rangabhashiyam; P, Balasubramanian

2018-05-12

Biosorption potential of novel lignocellulosic biosorbents Musa sp. peel (MSP) and Aegle marmelos shell (AMS) was investigated for the removal of toxic triphenylmethane dye malachite green (MG), from aqueous solution. Batch experiments were performed to study the biosorption characteristics of malachite green onto lignocellulosic biosorbents as a function of initial solution pH, initial malachite green concentration, biosorbents dosage, and temperature. Biosorption equilibrium data were fitted to two and three parameters isotherm models. Three-parameter isotherm models better described the equilibrium data. The maximum monolayer biosorption capacities obtained using the Langmuir model for MG removal using MSP and AMS was 47.61 and 18.86 mg/g, respectively. The biosorption kinetic data were analyzed using pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion models. The pseudo-second-order kinetic model best fitted the experimental data, indicated the MG biosorption using MSP and AMS as chemisorption process. The removal of MG using AMS was found as highly dependent on the process temperature. The removal efficiency of MG showed declined effect at the higher concentrations of NaCl and CaCl 2 . The regeneration test of the biosorbents toward MG removal was successful up to three cycles.

Spectrophotometric determination of boron by solvent extraction with 2-hydroxy-2-methylbutyric acid and malachite green

Energy Technology Data Exchange (ETDEWEB)

Sato, Shigeya; Uchikawa, Sumio [Kumamoto Univ. (Japan). Faculty of Education

1984-03-01

A very simple and sensitive method for the spectrophotometric determination of boron was developed. Boron was found to react with 2-hydroxy-2-methylbutyric acid in weak acidic aqueous solution at room temperature to form a complex anion which can be extracted into chlorobenzene with malachite green in a single extraction; boron is determined indirectly by measuring the absorbance of malachite green in the extract at 629 nm. The calibration graph is linear over the range (7.50 x 10/sup -7/ - 2.00 x 10/sup -5/) mol dm/sup -3/ boron; the apparent molar absorptivity is 6.50 x 10/sup 4/ dm/sup 3/ mol/sup -1/ cm/sup -1/. The method is applied to the determination of micro amounts of boron in natural waters with satisfactory results.

A Highly Sensitive and Selective Method for the Determination of an Iodate in Table-salt Samples Using Malachite Green-based Spectrophotometry.

Science.gov (United States)

Konkayan, Mongkol; Limchoowong, Nunticha; Sricharoen, Phitchan; Chanthai, Saksit

2016-01-01

A simple, rapid, and sensitive malachite green-based spectrophotometric method for the selective trace determination of an iodate has been developed and presented for the first time. The reaction mixture was specifically involved in the liberation of iodine in the presence of an excess of iodide in an acidic condition following an instantaneous reaction between the liberated iodine and malachite green dye. The optimum condition was obtained with a buffer solution pH of 5.2 in the presence of 40 mg L -1 potassium iodide and 1.5 × 10 -5 M malachite green for a 5-min incubation time. The iodate contents in some table-salt samples were in the range of 26 to 45 mg kg -1 , while those of drinking water, tap water, canal water, and seawater samples were not detectable (< 96 ng mL -1 of limits of detection, LOQ) with their satisfied method of recoveries of between 93 and 108%. The results agreed with those obtained using ICP-OES for comparison.

Factorial experimental design for the optimization of catalytic degradation of malachite green dye in aqueous solution by Fenton process

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A. Elhalil

2016-09-01

Full Text Available This work focuses on the optimization of the catalytic degradation of malachite green dye (MG by Fenton process “Fe2+/H2O2”. A 24 full factorial experimental design was used to evaluate the effects of four factors considered in the optimization of the oxidative process: concentration of MG (X1, concentration of Fe2+ (X2, concentration of H2O2 (X3 and temperature (X4. Individual and interaction effects of the factors that influenced the percentage of dye degradation were tested. The effect of interactions between the four parameters shows that there is a dependency between concentration of MG and concentration of Fe2+; concentration of Fe2+ and concentration of H2O2, expressed by the great values of the coefficient of interaction. The analysis of variance proved that, the concentration of MG, the concentration of Fe2+ and the concentration of H2O2 have an influence on the catalytic degradation while it is not the case for the temperature. In the optimization, the great dependence between observed and predicted degradation efficiency, the correlation coefficient for the model (R2=0.986 and the important value of F-ratio proved the validity of the model. The optimum degradation efficiency of malachite green was 93.83%, when the operational parameters were malachite green concentration of 10 mg/L, Fe2+ concentration of 10 mM, H2O2 concentration of 25.6 mM and temperature of 40 °C.

Polyvinyl butyral films containing leuco-malachite green as low-dose dosimeters

International Nuclear Information System (INIS)

Hoang Hoa Mai; Solomon, H.M.; Taguchi, M.; Kojima, T.

2008-01-01

Thin films containing leuco-malachite green (LMG) dye in polyvinyl butyral (PVB) have been developed for dose measurements of a few hundreds Gy level. The film shows significant color change in the visible range, and the sensitivity of the film to absorbed dose was enhanced by addition of chloride-containing compounds, such as chloral hydrate or 2,2,2-trichloroethanol. The film is suitable as dosimeters for dose measurements, e.g. in food irradiation and environmental protection

Home-Made Micro Valve for Determining Malachite Green Dye by Flow Injection Analysis

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Amal Saadoon Majeed

2017-07-01

Full Text Available The research is included studying and designing micro flow injection system which is characterized with rapidity, simplicity, and low cost for the determination of green malachite dye. The study of flow rate of carrier stream, repeatability, dispersion coefficient, and calibration graph are conducted. It is found that the optimum conditions for the determination of mentioned dye are flow rate 4.200 mL/min, sampling rate 102 sample/h, limit of detection 0.05 ppm, linear range (0.05-18.00 ppm with linearity (R2=0.9700, RSD is 0.355, the repeatability for seven successive injections is studied for the two concentrations 5 ppm and 12 ppm, and the dispersion coefficient values are 1.73 and 1.28 at the two concentrations 2 ppm and 9 ppm respectively.

Optical Properties of Malachite Green Dye Doped SiO2 Glasses: Effect of Transition Metal (Fe-I Used as a Codopant

Directory of Open Access Journals (Sweden)

Dulen Bora

2014-01-01

Full Text Available Enhanced luminescence properties of Malachite Green (MG (oxalate in Fe-MG codoped SiO2 glasses compared to its values in MG doped SiO2 glasses are reported here. The enhancement is chiefly attributed to a resonance nonradiative energy transfer between Fe and MG. The quantum yield of Malachite Green (MG, in presence of Iron, trapped in sol-gel derived SiO2 glass increases by an order of ~103 compared to that in low viscous solvent while a lifetime of 3.29 ns is reported.

Photocatalytic decouloration of malachite green dye by application of TiO2 nanotubes

International Nuclear Information System (INIS)

Prado, Alexandre G.S.; Costa, Leonardo L.

2009-01-01

The nanotubes of titania were synthesized in a hydrothermal system and characterized by scanning electronic microscopy (SEM), FT-IR, FT-Raman, and surface charge density by surface area analyzer. These nanomaterials were applied to photocatalyse malachite green dye degradation. Photodegradation capacity of TiO 2 nanotubes was compared to TiO 2 anatase photoactivity. Malachite dye was completely degraded in 75 and 105 min of reaction photocatalysed by TiO 2 nanotubes and TiO 2 anatase, respectively. Catalysts displayed high photodegradation activity at pH 4. TiO 2 nanotubes were easily recycled whereas the reuse of TiO 2 anatase was not effective. Nanotubes maintained 80% of their activity after 10 catalytic cycles and TiO 2 anatase presented only 8% of its activity after 10 cycles.

Investigation on removal of malachite green using EM based compost as adsorbent.

Science.gov (United States)

Bhagavathi Pushpa, T; Vijayaraghavan, J; Sardhar Basha, S J; Sekaran, V; Vijayaraghavan, K; Jegan, J

2015-08-01

The discarded materials from different sources can be utilized as effective materials in wastewater remediation. This proposed study was aimed mainly to investigate the possibility of Effective Microorganisms based compost (EMKC), which is derived from the kitchen solid waste, as a non-conventional low cost adsorbent for the removal of malachite green from aqueous solution. Batch experiments were carried out to evaluate the optimum operating parameters like pH (2-9), initial dye concentration (50-1000mg/L), adsorbent particle size (0.6-2.36mm) and adsorbent dosage (2-12g/L). EMKC recorded maximum uptake of 136.6mg/g of MG at pH 8, initial dye concentration 1000mg/L, adsorbent particle size 1.18mm and adsorbent dosage 4g/L. Two and three parameter adsorption models were employed to describe experimental biosorption isotherm data. The results revealed that the Sips model resulted in better fit than other models. The pseudo-first and -second order models were applied to describe kinetic data, of which the pseudo-second order described experimental data better with high correlation coefficient. This investigation suggested that EMKC could be an effective and low cost material for the removal of malachite green dye from aqueous solution. Copyright © 2015 Elsevier Inc. All rights reserved.

A high dose dosimeter based polyvinyl chloride dyed with malachite green

International Nuclear Information System (INIS)

Kattan, M.; Daher, Y.; Alkassiri, H.

2007-01-01

Polyvinyl chloride film (PVC) dyed with malachite green has been studied for high dose radiation dosimetry using visible spectrophotometry. A linear relationship between the relative absorbance and the absorbed dose at the wavelength 628 nm in the range of 0-125 kGy was found. The effect of dose rate, irradiation temperature, film thickness and dye intensity were found not to influence the response. The effects of shelf-life and the post-irradiation storage in darkness and indirect daylight conditions on dosimetry performance were discussed. (author)

Magnetic solid-phase extraction for determination of the total malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water by high-performance liquid chromatography with fluorescence detection.

Science.gov (United States)

Zhao, Jiao; Wei, Daqiao; Yang, Yaling

2016-06-01

In this study, magnetic multi-walled carbon nanotube nanoparticles were synthesized and used as the adsorbent for the sums of malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water samples followed by high performance liquid chromatography with fluorescence detection. This method was based on in situ reduction of chromic malachite green, gentian violet to colorless leucomalachite green, leucogentian violet with potassium borohydride, respectively. The obtained adsorbent combines the advantages of carbon nanotubes and Fe3 O4 nanoparticles in one material for separation and preconcentration of the reductive dyes in aqueous media. The structure and properties of the prepared nanoparticles were characterized by transmission and scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The main parameters affecting the adsorption recoveries were investigated and optimized, including reducing agent concentration, type and amount of sorbent, sample pH, and eluting conditions. Under the optimum conditions, the limits of detection in this method were 0.22 and 0.09 ng/mL for malachite green and gentian violet, respectively. Product recoveries ranged from 87.0 to 92.8% with relative standard deviations from 4.6 to 5.9%. The results indicate that the sorbent is a suitable material for the removal and concentration of triphenylmethane dyes from polluted environmental samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation of re-usable photocatalytic filter for degradation of Malachite Green dye under UV and vis-irradiation

International Nuclear Information System (INIS)

Sayilkan, F.; Asiltuerk, M.; Tatar, P.; Kiraz, N.; Arpac, E.; Sayilkan, H.

2007-01-01

Sn 4+ doped and undoped nano-TiO 2 particles easily dispersed in water were synthesized without using organic solvent by hydrothermal process. Nanostructure-TiO 2 based thin films were prepared on flyswatter substrate, made with stainless steel, by dip-coating technique. The structure, surface and optical properties of the particles and thin films were characterized by element analysis and XRD, BET, SEM and UV/vis/NIR techniques. The photocatalytic performance of the films were tested for degradation of Malachite Green dye in solution under UV and vis-lights. The results showed that the coated flyswatter has a very high photocatalytic performance for the photodegradation of Malachite Green irradiated with UV and vis-lights. The results also proved that the hydrothermally synthesized nano-TiO 2 particles are fully anatase crystalline form and are easily dispersed in water, the coated surfaces are hydrophilic, and the doping of transition metal ion efficiently improved the degradation performance of TiO 2 -coated flyswatter. The photocatalytic performances determined at both irradiation conditions were very good and were almost similar to each other for Sn 4+ doped TiO 2 -coated flyswatter and it can be repeatedly used with increasing photocatalytic activity compared to undoped TiO 2 -coated flyswatter

Mini-column assay for rapid detection of malachite green in fish.

Science.gov (United States)

Shalaby, Ali R; Emam, Wafaa H; Anwar, Mervat M

2017-07-01

A simple, rapid and economical mini-column method for detecting malachite green (MG) residue in fish was developed. The method used a column with 2mm ID that was tightly packed with silica gel followed by alumina. Detection of MG was performed by viewing the developed mini-column at visible light by naked eye; where MG was seen as compact green band at the confluence of the silica gel layer with alumina layer. The limit of detection of the assay was 2ng which conform the minimum required performance limit (MRPL). Evaluation utility of the method indicated that all blank and spiked samples at levels below MRPL were assessed as accepted. The intensity of the green band increased whenever MG level in the extract increased; indicated that suggested mini-column technique could be used for semi-quantitative determination of MG in fish samples. The method can be used to select the questionable samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Labeling RNAs in Live Cells Using Malachite Green Aptamer Scaffolds as Fluorescent Probes.

Science.gov (United States)

Yerramilli, V Siddartha; Kim, Kyung Hyuk

2018-03-16

RNAs mediate many different processes that are central to cellular function. The ability to quantify or image RNAs in live cells is very useful in elucidating such functions of RNA. RNA aptamer-fluorogen systems have been increasingly used in labeling RNAs in live cells. Here, we use the malachite green aptamer (MGA), an RNA aptamer that can specifically bind to malachite green (MG) dye and induces it to emit far-red fluorescence signals. Previous studies on MGA showed a potential for the use of MGA for genetically tagging other RNA molecules in live cells. However, these studies also exhibited low fluorescence signals and high background noise. Here we constructed and tested RNA scaffolds containing multiple tandem repeats of MGA as a strategy to increase the brightness of the MGA aptamer-fluorogen system as well as to make the system fluoresce when tagging various RNA molecules, in live cells. We demonstrate that our MGA scaffolds can induce fluorescence signals by up to ∼20-fold compared to the basal level as a genetic tag for other RNA molecules. We also show that our scaffolds function reliably as genetically encoded fluorescent tags for mRNAs of fluorescent proteins and other RNA aptamers.

Photocatalytic degradation of malachite green dye using Au/NaNbO_3 nanoparticles

International Nuclear Information System (INIS)

Baeissa, E.S.

2016-01-01

The morphology of sodium niobate, which was produced using a hydrothermal method, was studied by changing the hydrothermal temperature from 100 to 250 °C. Using 250 °C hydrothermal temperature resulted in sodium niobate with a nanocube structure. The sodium niobate nanocubes were doped with gold by impregnation with an aqueous solution of HAuCl_4. The band gap of sodium niobate is approximately 3.4 eV, and it was decreased to 2.45 eV by gold doping. The surface area of sodium niobate is higher than that of Au/NaNbO_3 due to blockage of some pores of sodium niobate by gold doping. The photocatalytic performance of gold-doped sodium niobate was studied by degradation of malachite green dye using visible light irradiation. The results demonstrate that the photocatalytic performance of gold-doped sodium niobate is higher than that of sodium niobate and TiO_2 Degussa under visible light irradiation. - Highlights: • Au/NaNbO_3 were used for photocatalytic degradation of malachite green dye. • Photocatalytic degradation was dependent on wt % of Au; reaction time, and weight of catalyst. • Catalyst re-use revealed the present photocatalyst remain effective and active after five cycles.

Malachite green adsorption onto natural zeolite and reuse by microwave irradiation

International Nuclear Information System (INIS)

Han Runping; Wang Yu; Sun Qing; Wang Lulu; Song Jiyun; He Xiaotian; Dou Chanchan

2010-01-01

Natural zeolite was used for the removal of malachite green (MG) from aqueous solution in batch mode and reused by microwave irradiation. The isotherm data were analyzed by the Langmuir, Freundlich, Redlich-Peterson, and Koble-Corrigan isotherm model. The better fit for the equilibrium process was Koble-Corrigan model. The kinetic studies indicated that the adsorption followed the pseudo-second-order kinetic. Thermodynamic calculations showed that the adsorption was spontaneous and endothermic process. Spent zeolite was treated by microwave irradiation and it was found that yield of regeneration was 85.8% in the case of microwave irradiated time 10 min at 160 W.

HPLC Determination and MS Confirmation of Malachite Green, Gentian Violet, and Their Leuco Metabolites in Catfish Muscle

Science.gov (United States)

Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in catfish muscle were individually determined by HPLC using visible and fluorescence detectors. This detection scheme obviated a PbO2 column that converts leuco forms to chromatic forms for visible detection, thus el...

Post-column reaction for simultaneous analysis of chromatic and leuco forms of malachite green and crystal violet by high-performance liquid chromatography with photometric detection

Science.gov (United States)

Allen, J.L.; Meinertz, J.R.

1991-01-01

The chromatic and leuco forms of malachite green and crystal violet were readily separated and detected by a sensitive and selective high-performance liquid chromatographic procedure. The chromatic and leuco forms of the dyes were separated within 11 min on a C18 column with a mobile phase of 0.05 M sodium acetate and 0.05 M acetic acid in water (19%) and methanol (81%). A reaction chamber, containing 10% PbO2 in Celite 545, was placed between the column and the spectrophotometric detector to oxidize the leuco forms of the dyes to their chromatic forms. Chromatic and leuco malachite green were quantified by their absorbance at 618 nm; and chromatic and leuco Crystal Violet by their absorbance at 588 nm. Detection limits for chromatic and leuco forms of both dyes ranged from 0.12 to 0.28 ng. A linear range of 1 to 100 ng was established for both forms of the dyes.

Degradation of malachite green in aqueous solution by Fenton process.

Science.gov (United States)

Hameed, B H; Lee, T W

2009-05-30

In this study, advanced oxidation process utilizing Fenton's reagent was investigated for degradation of malachite green (MG). The effects of different reaction parameters such as the initial MG concentration, initial pH, the initial hydrogen peroxide concentration, the initial ferrous concentration and the reaction temperature on the oxidative degradation of MG have been investigated. The optimal reacting conditions were experimentally found to be pH 3.40, initial hydrogen peroxide concentration=0.50mM and initial ferrous concentration=0.10mM for initial MG concentration of 20mg/L at 30 degrees C. Under optimal conditions, 99.25% degradation efficiency of dye in aqueous solution was achieved after 60 min of reaction.

Pathway and Molecular Mechanisms for Malachite Green Biodegradation in Exiguobacterium sp. MG2

Science.gov (United States)

Wang, Ji’ai; Gao, Feng; Liu, Zhongzhong; Qiao, Min; Niu, Xuemei; Zhang, Ke-Qin; Huang, Xiaowei

2012-01-01

Malachite green (MG), N-methylated diaminotriphenylmethane, is one of the most common dyes in textile industry and has also been used as an effective antifungal agent. However, due to its negative impact on the environment and carcinogenic effects to mammalian cells, there is a significant interest in developing microbial agents to degrade this type of recalcitrant molecules. Here, an Exiguobacterium sp. MG2 was isolated from a river in Yunnan Province of China as one of the best malachite green degraders. This strain had a high decolorization capability even at the concentration of 2500 mg/l and maintained its stable activity within the pH range from 5.0 to 9.0. High-pressure liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography–mass spectrometry were employed to detect the catabolic pathway of MG. Six intermediate products were identified and a potential biodegradation pathway was proposed. This pathway involves a series of reactions of N-demethylation, reduction, benzene ring-removal, and oxidation, which eventually converted N-methylated diaminotriphenylmethane into N, N-dimethylaniline that is the key precursor to MG. Furthermore, our molecular biology experiments suggested that both triphenylmethane reductase gene tmr and cytochrome P450 participated in MG degradation, consistent with their roles in the proposed pathway. Collectively, our investigation is the first report on a biodegradation pathway of triphenylmethane dye MG in bacteria. PMID:23251629

Photocatalytic degradation of malachite green dye using Au/NaNbO{sub 3} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Baeissa, E.S., E-mail: elhambaeissa@gmail.com

2016-07-05

The morphology of sodium niobate, which was produced using a hydrothermal method, was studied by changing the hydrothermal temperature from 100 to 250 °C. Using 250 °C hydrothermal temperature resulted in sodium niobate with a nanocube structure. The sodium niobate nanocubes were doped with gold by impregnation with an aqueous solution of HAuCl{sub 4}. The band gap of sodium niobate is approximately 3.4 eV, and it was decreased to 2.45 eV by gold doping. The surface area of sodium niobate is higher than that of Au/NaNbO{sub 3} due to blockage of some pores of sodium niobate by gold doping. The photocatalytic performance of gold-doped sodium niobate was studied by degradation of malachite green dye using visible light irradiation. The results demonstrate that the photocatalytic performance of gold-doped sodium niobate is higher than that of sodium niobate and TiO{sub 2} Degussa under visible light irradiation. - Highlights: • Au/NaNbO{sub 3} were used for photocatalytic degradation of malachite green dye. • Photocatalytic degradation was dependent on wt % of Au; reaction time, and weight of catalyst. • Catalyst re-use revealed the present photocatalyst remain effective and active after five cycles.

Removal of malachite green dye from aqueous solution using mesoporous silica synthesized from 1-octyl-3-methylimidazolium chloride ionic liquid

International Nuclear Information System (INIS)

Ekka, Basanti; Nayak, Soumitra Ranjan; Dash, Priyabrat; Patel, Raj Kishore

2016-01-01

In this research, mesoporous silica was synthesized via a modified sol-gel route using 1-octyl-3-methylimidazolium chloride and was employed to remove malachite green (MG) dye from aqueous solution. Subsequently, this material was characterized and identified by different techniques such as Fourier transform infrared spectroscopy (FT-IR), N_2 adsorption-desorption method, scanning electron microscopy (SEM), and thermosgravimetric analysis (TGA). Unique properties such as high surface area and pore diameter, in addition to highly reactive atoms and presence of various functional groups make the mesoporous silica possible for efficient removal of malachite green (MG). In batch experimental set-up, optimum conditions for quantitative removal of MG by mesoporous silica was attained by varying different variables such as adsorbent dosage, initial dye concentration, contact time, and pH. Optimum values were set as pH of 8.0, 0.5 g of adsorbent at contact time of 120 min. The adsorption of MG follows the pseudo-second-order rate equation. Equilibrium data fitted well with the Freundlich model at all amount of adsorbent, while maximum adsorption capacity was 5.981 mg g"−1 for 0.5 g mesoporous silica synthesized in IL.

Application of Micro-cloud point extraction for spectrophotometric determination of Malachite green, Crystal violet and Rhodamine B in aqueous samples

Science.gov (United States)

Ghasemi, Elham; Kaykhaii, Massoud

2016-07-01

A novel, green, simple and fast method was developed for spectrophotometric determination of Malachite green, Crystal violet, and Rhodamine B in water samples based on Micro-cloud Point extraction (MCPE) at room temperature. This is the first report on the application of MCPE on dyes. In this method, to reach the cloud point at room temperature, the MCPE procedure was carried out in brine using Triton X-114 as a non-ionic surfactant. The factors influencing the extraction efficiency were investigated and optimized. Under the optimized condition, calibration curves were found to be linear in the concentration range of 0.06-0.60 mg/L, 0.10-0.80 mg/L, and 0.03-0.30 mg/L with the enrichment factors of 29.26, 85.47 and 28.36, respectively for Malachite green, Crystal violet, and Rhodamine B. Limit of detections were between 2.2 and 5.1 μg/L.

Cherenkov light as a source of photochemical reactions in irradiated solutions of nitrile of malachite green

Energy Technology Data Exchange (ETDEWEB)

Stuglik, Z; Grodkowski, J

1986-10-01

Experimental data on photochemical activity of Cherenkov light are presented. Malachite green leucocyanide was used to detect the photochemical effects. The G value of Cherenkov light from the region 200-330 nm (number of quanta formed per 100 eV absorbed energy of ionizing radiation) in ethanol was estimated to be in the range of 0.0027-0.049. 14 references.

Cherenkov light as a source of photochemical reactions in irradiated solutions of nitrile of malachite green

International Nuclear Information System (INIS)

Stuglik, Z.; Grodkowski, J.

1986-01-01

Experimental data on photochemical activity of Cherenkov light are presented. Malachite green leucocyanide was used to detect the photochemical effects. The G value of Cherenkov light from the region 200-330 nm (number of quanta formed per 100 eV absorbed energy of ionizing radiation) in ethanol was estimated to be in the range of 0.0027-0.049. (author)

Application of Taguchi L16 design method for comparative study of ability of 3A zeolite in removal of Rhodamine B and Malachite green from environmental water samples

Science.gov (United States)

Rahmani, Mashaallah; Kaykhaii, Massoud; Sasani, Mojtaba

2018-01-01

This study aimed to investigate the efficiency of 3A zeolite as a novel adsorbent for removal of Rhodamine B and Malachite green dyes from water samples. To increase the removal efficiency, effecting parameters on adsorption process were investigated and optimized by adopting Taguchi design of experiments approach. The percentage contribution of each parameter on the removal of Rhodamine B and Malachite green dyes determined using ANOVA and showed that the most effective parameters in removal of RhB and MG by 3A zeolite are initial concentration of dye and pH, respectively. Under optimized condition, the amount predicted by Taguchi design method and the value obtained experimentally, showed good closeness (more than 94.86%). Good adsorption efficiency obtained for proposed methods indicates that, the 3A zeolite is capable to remove the significant amounts of Rhodamine B and Malachite green from environmental water samples.

Photocatalytic performance of Sn-doped TiO2 nanostructured thin films for photocatalytic degradation of malachite green dye under UV and VIS-lights

International Nuclear Information System (INIS)

Sayilkan, F.; Asiltuerk, M.; Tatar, P.; Kiraz, N.; Sener, S.; Arpac, E.; Sayilkan, H.

2008-01-01

Sn-doped and undoped nano-TiO 2 particles have been synthesized by hydrotermal process without acid catalyst at 225 deg. C in 1 h. Nanostructure-TiO 2 based thin films, contain at different solid ratio of TiO 2 in coating, have been prepared on glass surfaces by spin-coating technique. The structure, surface morphology and optical properties of the thin films and the particles have been investigated by element analysis and XRD, BET and UV/VIS/NIR techniques. The photocatalytic performance of the films was tested for degradation of malachite green dye in solution under UV and VIS-lights. The results showed that the hydrothermally synthesized nano-TiO 2 particles are fully anatase crystalline form and are easily dispersed in water, the coated surfaces have nearly super-hydrophilic properties and, the doping of transition metal ion efficiently improved the photocatalytic performance of the TiO 2 thin film. The results also proved that malachite green is decomposed catalytically due to the pseudo first-order reaction kinetics

Photocatalytic Degradation of Malachite Green Using Nano-sized cerium-iron Oxide

Directory of Open Access Journals (Sweden)

K. L. Ameta

2014-05-01

Full Text Available Nano-sized cerium-iron oxide nanoparticles has been synthesized, characterized and explored as an efficient photocatalyst for the photocatalytic degradation of malachite green. The effects of different variables on degradation of dye were optimized such as the pH of the dye solution, dye concentration, amount of photocatalyst and light intensity. About 91% degradation of dye of 2×10-5 M concentration was observed after 2 hours at 8.5 pH and 600 Wm-2 light intensity. The reason for the high catalytic activity of the synthesized nanoparticles is ascribed to the high surface area which determines the active sites of the catalyst and accelerates the photocatalytic degradation.

DC conduction mechanism and dielectric properties of Poly (methyl methacrylate)/Poly (vinyl acetate) blends doped and undoped with malachite green

International Nuclear Information System (INIS)

Abd-El Kader, F.H.; Osman, W.H.; Hafez, R.S.

2013-01-01

Cast thin films of Poly (methyl methacrylate)/Poly (vinyl acetate) blends of different concentrations undoped and doped with malachite green have been prepared and subjected to both dc electrical conduction and dielectric spectroscopy measurements. The analysis of dc electrical conduction data showed that the space charge limited current mechanism has been dominant for Poly (vinyl acetate) while Schottky-Richardson conduction mechanism prevailed for the Poly (methyl methacrylate) and blended samples. The values of field lowering constant β and the thermal activation energy ΔE involved in the dc conduction were reported, which provide another support for the suggested Schottky-Richardson mechanism. The increase in current for the blend sample doped with malachite green has been attributed to the formation of charge transfer complexes inside the polyblend matrix. The dielectric constant as a function of temperature for all samples have been calculated which are affected by the composition ratio and the addition of dye. The relaxation peak that appeared in the dielectric loss curve at 347 K for the doped blend sample is related to local dipoles that are present in the dye material. The obtained relaxation process spectra present in the investigated samples were analyzed with the well-known model of Havriliak-Negami.

Adsorption kinetics of malachite green onto activated carbon prepared from Tuncbilek lignite

International Nuclear Information System (INIS)

Onal, Y.; Akmil-Basar, C.; Eren, Didem; Sarici-Ozdemir, Cigdem; Depci, Tolga

2006-01-01

Adsorbent (T 3 K618) has been prepared from Tuncbilek lignite by chemical activation with KOH. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by t-plot based on N 2 adsorption isotherm. The N 2 adsorption isotherm of malachite green on T 3 K618 is type I. The BET surface area of the adsorbent which was primarily contributed by micropores was determined 1000 m 2 /g. T 3 K618 was used to adsorb malachite green (MG) from an aqueous solution in a batch reactor. The effects of initial dye concentration, agitation time, initial pH and adsorption temperature have been studied. It was also found that the adsorption isotherm followed both Freundlich and Dubinin-Radushkevich models. However, the Freundlich gave a better fit to all adsorption isotherms than the Dubinin-Radushkevich. The kinetics of adsorption of MG has been tested using pseudo-first-order, pseudo-second-order and intraparticle diffusion models. Results show that the adsorption of MG from aqueous solution onto micropores T 3 K618 proceeds according to the pseudo-second-order model. The intraparticle diffusion of MG molecules within the carbon particles was identified to be the rate-limiting step. The adsorption of the MG was endothermic (ΔH o = 6.55-62.37 kJ/mol) and was accompanied by an increase in entropy (ΔS o = 74-223 J/mol K) and a decrease in mean value of Gibbs energy (ΔG o = -6.48 to -10.32 kJ/mol) in the temperature range of 20-50 deg. C

EFSA CONTAM Panel (EFSA Panel on Contaminants in the Food Chain), 2016. Scientific opinion on malachite green in food

DEFF Research Database (Denmark)

Petersen, Annette

Malachite green (MG) has been used globally in aquaculture but is not registered for use infood-producing animals in the European Union. The European Commission requested EFSA to evaluatewhether a reference point for action (RPA) of 2 lg/kg for the sum of MG and its major metaboliteleucomalachite...

Removal of Malachite Green from water using hydrothermally carbonized pine needles

KAUST Repository

Hammud, Hassan Hasan

2015-01-01

Hydrothermal carbonization of pine needles (HTC-PN) and their oxidized-activated form HTC-APN are prepared and applied for the adsorption of Malachite Green (MG) in aqueous solution. The HTC materials were characterized by thermal and TEM analysis. Adsorbent dose, initial concentration of MG, contact time, temperature and pH effect on MG adsorption onto the HTC materials were studied. The adsorption equilibrium data was best fitted by the Langmuir isotherm model and the adsorption kinetics followed pseudo-second-order models for both HTC-PN and HTC-APN. The maximum capacity predicted by the Langmuir nonlinear model is 52.91 and 97.08 mg g-1 for uptake of MG by HTC-PN and HTC-APN, respectively, at 30 °C. Thermodynamic investigations showed that the adsorption is spontaneous and endothermic in nature. Results suggest HTC-APN can be used as a low-cost adsorbent for MG removal from industrial wastewater. Yoon-Nelson is the best model with a column capacity of 38.3 mg g-1 for the adsorption of MG onto HTC-APN. This journal is

Synthesis of novel laccase-biotitania biocatalysts for malachite green decolorization.

Science.gov (United States)

Zhang, Xinying; Wang, Meiyin; Lin, Linlin; Xiao, Gao; Tang, Zhenping; Zhu, Xuefeng

2018-07-01

Biomimetic mineralization has emerged as a novel tool for generating excellent supports for enzyme stabilization. In this work, protamine was used to induce titanium (IV) bis(ammonium lactato) dihydroxide (Ti-BALDH) into titania nanoparticles. This biomimetic titanification process was adopted for laccase immobilization. Laccase-biotitania biocatalyst was prepared and the effect of different parameters (buffer solution, titania precursor concentration, protamine concentration, and enzyme loading) on the encapsulation efficiency and recovery of laccase were evaluated. Compared with free laccase, the thermal and pH stability of immobilized laccase were improved significantly. In addition, laccase loaded on titania was effective at enhancing its storage stability. After seven consecutive cycles, the immobilized laccase still retained 51% of its original activity. Finally, laccase-biotitania biocatalysts showed good performance on decolorization of malachite green (MG), which can be attributed to an adsorption and degradation effect. The intermediates of the MG degradation were identified by gas chromatography-mass spectrometry (GC-MS) analysis, and the most probable degradation pathway was proposed. This study provides deeper understanding of the laccase-biotitania particles as a fast biocatalyst for MG decolorization. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Removal of malachite green by adsorption and precipitation using aminopropyl functionalized magnesium phyllosilicate

International Nuclear Information System (INIS)

Lee, Young-Chul; Kim, Eui Jin; Yang, Ji-Won; Shin, Hyun-Jae

2011-01-01

Highlights: → Preparation of aminopropyl functionalized magnesium phyllosilicate (AMP clay). → Characterization of AMP clay and AMP clay-malachite green (MG) mixture. → Novel precipitation mechanism including MG fading plus collapsed AMP clay. → Adsorption kinetics and thermodynamics of MG using AMP clay. - Abstract: We report a method for the removal of malachite green (MG) by adsorption and precipitation using nano-sized aminopropyl functionalized magnesium phyllosilicate (AMP) clay. MG, which is used in aquaculture and fisheries, is a carcinogenic and mutagenic compound. In response to these health risks, many efforts have been focused on adsorption of MG onto various adsorbents, which is a versatile and widely used technique for removing MG from water. Herein, we describe the adsorption and precipitation of MG using AMP clay, as well as the alkaline fading phenomenon of MG. In this study, prepared AMP clay and the precipitate product after the reaction of MG-AMP clay mixture were characterized. In addition, adsorption isotherms and kinetics, as well as thermodynamic studies are presented. Based on the results, we suggest a macro- and microscopic removal mechanism for the adsorption and precipitation of MG using AMP clay. An AMP clay dosage of 0.1 mg mL -1 exhibited a maximum removal capacity of 334.80 mg g -1 and 81.72% MG removal efficiency. With further increases of the AMP clay dosage, removal capacity by AMP clay gradually decreased; at dosage above 0.2 mg mL -1 of AMP clay, the removal efficiency reached 100%.

Removal of malachite green by adsorption and precipitation using aminopropyl functionalized magnesium phyllosilicate

Energy Technology Data Exchange (ETDEWEB)

Lee, Young-Chul [Department of Chemical and Biomolecular Engineering (BK21 Program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Eui Jin [Department of Chemical and Biochemical Engineering, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Yang, Ji-Won [Department of Chemical and Biomolecular Engineering (BK21 Program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Shin, Hyun-Jae, E-mail: shinhj@chosun.ac.kr [Department of Chemical and Biochemical Engineering, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of)

2011-08-15

Highlights: {yields} Preparation of aminopropyl functionalized magnesium phyllosilicate (AMP clay). {yields} Characterization of AMP clay and AMP clay-malachite green (MG) mixture. {yields} Novel precipitation mechanism including MG fading plus collapsed AMP clay. {yields} Adsorption kinetics and thermodynamics of MG using AMP clay. - Abstract: We report a method for the removal of malachite green (MG) by adsorption and precipitation using nano-sized aminopropyl functionalized magnesium phyllosilicate (AMP) clay. MG, which is used in aquaculture and fisheries, is a carcinogenic and mutagenic compound. In response to these health risks, many efforts have been focused on adsorption of MG onto various adsorbents, which is a versatile and widely used technique for removing MG from water. Herein, we describe the adsorption and precipitation of MG using AMP clay, as well as the alkaline fading phenomenon of MG. In this study, prepared AMP clay and the precipitate product after the reaction of MG-AMP clay mixture were characterized. In addition, adsorption isotherms and kinetics, as well as thermodynamic studies are presented. Based on the results, we suggest a macro- and microscopic removal mechanism for the adsorption and precipitation of MG using AMP clay. An AMP clay dosage of 0.1 mg mL{sup -1} exhibited a maximum removal capacity of 334.80 mg g{sup -1} and 81.72% MG removal efficiency. With further increases of the AMP clay dosage, removal capacity by AMP clay gradually decreased; at dosage above 0.2 mg mL{sup -1} of AMP clay, the removal efficiency reached 100%.

Molecular cloning, characterization and expression of heat shock protein 70 gene from the oyster Crassostrea hongkongensis responding to thermal stress and exposure of Cu(2+) and malachite green.

Science.gov (United States)

Zhang, Zhanhui; Zhang, Qizhong

2012-04-15

Heat shock protein 70 (HSP70) acts mostly as a molecular chaperone and plays a key role in the process of protecting cells by facilitating the folding of nascent peptides and the cellular stress response. The cDNA of the oyster Crassostrea hongkongensis hsp70 (designated chhsp70) was cloned with the techniques of homological cloning and rapid amplification of cDNA ends (RACE). The full-length chhsp70 cDNA was 2251bp, consisting of a 130bp 5'-UTR, 216bp 3'-UTR with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 1905bp, which encoded a polypeptide of 634 amino acids. Three classical HSP signature motifs were detected in ChHSP70, i.e., DLGTT-S-V, IFDLGGGTFDVSIL and VVLVGGSTRIPKIQK. BLAST analysis revealed that the ChHSP70 shared high identity with other bivalve HSP70. The phylogenetic analysis indicated that the ChHSP70 was a member of the HSP70 family. The chhsp70 mRNA transcripts were quantified by fluorescent real time RT-PCR under both unstressed and stressed conditions, i. e., heat shock and exposure to Cu(2+) and malachite green. Basal expression level was similar in mantle, gill, digestive gland, and heart, but higher in muscle than that in the others. A similar trend showed that the chhsp70 mRNA expression significantly increased at 3-6h, then dropped and returned to control level at 24h in the five tissues and organs mentioned above after heat shock. A clearly time-dependent expression pattern of chhsp70 mRNA in digestive gland and gill of the oyster was observed after exposure of Cu(2+) and malachite green. In the two tissues, the chhsp70 mRNA level reached the maximum at 6h after malachite green exposure and on day 4 after Cu(2+) exposure, and then decreased progressively to the control level. The results indicated that ChHSP70 of the oyster is an inducible protein, and plays an important role in response to the Cu(2+) and malachite green polluted stress, so chhsp70 might be used as a potential molecular

Removal of Malachite Green Dye by Mangifera indica Seed Kernel Powder

Science.gov (United States)

Singh, Dilbagh; Sowmya, V.; Abinandan, S.; Shanthakumar, S.

2017-11-01

In this study, batch experiments were carried out to study the adsorption of Malachite green dye from aqueous solution by Mangifera indica (mango) seed kernel powder. The mango seed kernel powder was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Effect of various parameters including pH, contact time, adsorbent dosage, initial dye concentration and temperature on adsorption capacity of the adsorbent was observed and the optimized condition for maximum dye removal was identified. Maximum percentage removal of 96% was achieved with an adsorption capacity of 22.8 mg/g at pH 6 with an initial concentration of 100 mg/l. The equilibrium data were examined to fit the Langmuir and Freundlich isotherm models. Thermodynamic parameters for the adsorption process were also calculated.

Cationic dyes as extraction and spectrophotometric reagents: extraction of thiocyanate complex of mercury (II) in association with malachite green

Energy Technology Data Exchange (ETDEWEB)

Iyer, N V; Murthy, T K.S.

1975-01-01

An extraction spectrophotometric method for the determination of Hg(II) is described. This is based on the extraction of Hg(CNS)/sub 3//sup -/ complex in association with the cation of malachite green into benzene. The benzene extract has lambda max at 640 mm. Maximal extraction takes place from an aqueous solution of pH 4.5. Although four extractions are needed for quantitative recovery of Hg(II), a single extraction with aqueous organic = 2.5 : 1 is recommended for analysis and the apparent molar absorptivity is 65,000. The interference from a number of anions and cations has also been studied. (auth)

Green synthesized conditions impacting on the reactivity of Fe NPs for the degradation of malachite green.

Science.gov (United States)

Huang, Lanlan; Luo, Fang; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

2015-02-25

This study investigates green tea extract synthesized conditions impacting on the reactivity of iron nanoparticles (Fe NPs) used for the degradation of malachite green (MG), including the volume ratio of Fe(2+) and tea extract, the solution pH and temperature. Results indicated that the reactivity of Fe NPs increased with higher temperature, but fell with increasing pH and the volume ratio of Fe(2+) and tea extract. Scanning electron microscope (SEM), energy-dispersive spectrometer (EDS), Fourier transform infrared spectroscope (FTIR) and X-ray diffraction (XRD) indicated that Fe NPs were spherical in shape, their diameter was 70-80 nm and they were mainly composed of iron oxide nanoparticles. UV-visible (UV-vis) indicated that reactivity of Fe NPs used in degradation of MG significantly depended on the synthesized conditions of Fe NPs. This was due to their impact on the reactivity and morphology of Fe NPs. Finally, degradation of MG showed that 90.56% of MG was removed using Fe NPs. Copyright © 2014 Elsevier B.V. All rights reserved.

Rapid and sensitive detection of malachite green in aquaculture water by electrochemical preconcentration and surface-enhanced Raman scattering.

Science.gov (United States)

Xu, Kai-Xuan; Guo, Mei-Hong; Huang, Yu-Ping; Li, Xiao-Dong; Sun, Jian-Jun

2018-04-01

A highly sensitive and rapid method of in-situ surface-enhanced Raman spectroscopy (SERS) combining with electrochemical preconcentration (EP) in detecting malachite green (MG) in aquaculture water was established. Ag nanoparticles (AgNPs) were synthesized and spread onto the surface of gold electrodes after centrifuging to produce SERS-active substrates. After optimizing the pH values, preconcentration potentials and times, in-situ EP-SERS detection was carried out. A sensitive and rapid analysis of the low-concentration MG was accomplished within 200s and the limit of detection was 2.4 × 10 -16 M. Copyright © 2017 Elsevier B.V. All rights reserved.

Anatase/rutile TiO2 composites: Influence of the mixing ratio on the photocatalytic degradation of Malachite Green and Orange II in slurry

International Nuclear Information System (INIS)

Bojinova, A.; Kralchevska, R.; Poulios, I.; Dushkin, C.

2007-01-01

The present study is directed to clarify the influence of the ratio of anatase to rutile phase, containing in the TiO 2 samples, on their activity as photocatalysts in slurry. A series of samples corresponding to different percentages of anatase is prepared from commercial anatase and rutile TiO 2 brands (KRONOS). The crystalline phase composition of the samples is characterized by X-ray diffraction. The photocatalytic action of the mixtures is tested in photodegradation of the commercial organic dyes Malachite Green Hydrochloride and Orange II in aqueous solutions under UV irradiation. Comparative tests with Degussa P-25 are performed. The apparent rate constants of the process are determined from the kinetic curves using appropriate models. They generally increase with the anatase ratio, being always larger for Malachite Green than for Orange II

Synthesis and characterization of N-demethylated metabolites of malachite green and leucomalachite green.

Science.gov (United States)

Cho, Bongsup P; Yang, Tianle; Blankenship, Lonnie R; Moody, Joanna D; Churchwell, Mona; Beland, Frederick A; Culp, Sandra J

2003-03-01

Malachite green (MG), a triphenylmethane dye used to treat fungal and protozoan infections in fish, undergoes sequential oxidation to produce various N-demethylated derivatives (monodes-, dides(sym)-, dides(unsym)-, trides-, and tetrades-) both before and after reduction to leucomalachite green (LMG). The close structure resemblance of the metabolites with aromatic amine carcinogens implicates a potential genotoxicity from exposure to MG. The availability of the synthetic standards is important for metabolic and DNA adduct studies of MG. This paper describes a simple and versatile method for the synthesis of MG, LMG, and their N-demethylated metabolites. The synthesis involves a coupling of 4-(dimethylamino)benzophenone or 4-nitrobenzophenone with the aryllithium reagents derived from appropriately substituted 4-bromoaniline derivatives, followed by treatment with HCl in methanol. The resulting cationic MG and their leuco analogues showed systematic UV/vis spectral and tandem mass fragmentation patterns consistent with sequential N-demethylation. The extensive (1)H and (13)C spectral assignments of the metabolites were aided by the availability of (13)C(7)-labeled MG and LMG. The results indicate the existence of a resonance structure with the cationic charge located in the central methane carbon (C(7)). The synthetic procedure is general in scope so that it can be extended to the preparation of N-demethylated metabolites of other structurally related N-methylated triphenylmethane dyes.

Incorporation of flow injection analysis with dual-wavelength overlapping resonance Rayleigh scattering for rapid determination of malachite green and its metabolite in fish.

Science.gov (United States)

Zhu, Jinghui; Qin, Mingyou; Liu, Shaopu; Liu, Zhongfang; Yang, Jidong; Hu, Xiaoli

2014-09-15

A flow injection analysis (FIA) system combined with dual-wavelength overlapping resonance Rayleigh scattering (DWO-RRS) has been established and validated for rapid determination of malachite green (MG) and its metabolite in fish samples. Under experimental condition, MG would react with Erythrosin (Ery) to form ion-association complexes, resulting in the occurrence of two RRS peaks and a dramatic enhancement of RRS intensity. The maximum RRS peaks were located at 286 nm and 337 nm. It is noted that the increments of both of these two peaks were proportional to the concentration of MG. The detection limit of DWO-RRS was 1.5 ng/mL, which was comparable to several reported methods. Moreover, the results of real sample analysis exhibited an acceptable recovery between 97.5% and 103.6%, indicating that the method had good reproducibility. Copyright © 2014 Elsevier B.V. All rights reserved.

An enzyme-free strategy for ultrasensitive detection of adenosine using a multipurpose aptamer probe and malachite green.

Science.gov (United States)

Zhao, Hui; Wang, Yong-Sheng; Tang, Xian; Zhou, Bin; Xue, Jin-Hua; Liu, Hui; Liu, Shan-Du; Cao, Jin-Xiu; Li, Ming-Hui; Chen, Si-Han

2015-08-05

We report on an enzyme-free and label-free strategy for the ultrasensitive determination of adenosine. A novel multipurpose adenosine aptamer (MAAP) is designed, which serves as an effective target recognition probe and a capture probe for malachite green. In the presence of adenosine, the conformation of the MAAP is converted from a hairpin structure to a G-quadruplex. Upon addition of malachite green into this solution, a noticeable enhancement of resonance light scattering was observed. The signal response is directly proportional to the concentration of adenosine ranging from 75 pM to 2.2 nM with a detection limit of 23 pM, which was 100-10,000 folds lower than those obtained by previous reported methods. Moreover, this strategy has been applied successfully for detecting adenosine in human urine and blood samples, further proving its reliability. The mechanism of adenosine inducing MAAP to form a G-quadruplex was demonstrated by a series of control experiments. Such a MAAP probe can also be used to other strategies such as fluorescence or spectrophotometric ones. We suppose that this strategy can be expanded to develop a universal analytical platform for various target molecules in the biomedical field and clinical diagnosis. Copyright © 2015 Elsevier B.V. All rights reserved.

Laccase-Catalyzed Decolorization of Malachite Green: Performance Optimization and Degradation Mechanism

Science.gov (United States)

Yang, Jie; Yang, Xiaodan; Lin, Yonghui; Ng, Tzi Bun; Lin, Juan; Ye, Xiuyun

2015-01-01

Malachite green (MG) was decolorized by laccase (LacA) of white-rot fungus Cerrena sp. with strong decolorizing ability. Decolorization conditions were optimized with response surface methodology. A highly significant quadratic model was developed to investigate MG decolorization with LacA, and the maximum MG decolorization ratio of 91.6% was predicted under the conditions of 2.8 U mL-1 LacA, 109.9 mg L-1 MG and decolorization for 172.4 min. Kinetic studies revealed the Km and kcat values of LacA toward MG were 781.9 mM and 9.5 s-1, respectively. UV–visible spectra confirmed degradation of MG, and the degradation mechanism was explored with liquid chromatography–mass spectrometry (LC-MS) analysis. Based on the LC-MS spectra of degradation products, LacA catalyzed MG degradation via two simultaneous pathways. In addition, the phytotoxicity of MG, in terms of inhibition on seed germination and seedling root elongation of Nicotiana tabacum and Lactuca sativa, was reduced after laccase treatment. These results suggest that laccase of Cerrena was effective in decolorizing MG and promising in bioremediation of wastewater in food and aquaculture industries. PMID:26020270

Laccase-catalyzed decolorization of malachite green: performance optimization and degradation mechanism.

Directory of Open Access Journals (Sweden)

Jie Yang

Full Text Available Malachite green (MG was decolorized by laccase (LacA of white-rot fungus Cerrena sp. with strong decolorizing ability. Decolorization conditions were optimized with response surface methodology. A highly significant quadratic model was developed to investigate MG decolorization with LacA, and the maximum MG decolorization ratio of 91.6% was predicted under the conditions of 2.8 U mL(-1 LacA, 109.9 mg L(-1 MG and decolorization for 172.4 min. Kinetic studies revealed the Km and kcat values of LacA toward MG were 781.9 mM and 9.5 s(-1, respectively. UV-visible spectra confirmed degradation of MG, and the degradation mechanism was explored with liquid chromatography-mass spectrometry (LC-MS analysis. Based on the LC-MS spectra of degradation products, LacA catalyzed MG degradation via two simultaneous pathways. In addition, the phytotoxicity of MG, in terms of inhibition on seed germination and seedling root elongation of Nicotiana tabacum and Lactuca sativa, was reduced after laccase treatment. These results suggest that laccase of Cerrena was effective in decolorizing MG and promising in bioremediation of wastewater in food and aquaculture industries.

Adsorptive removal of malachite green from aqueous solutions by almond gum: Kinetic study and equilibrium isotherms.

Science.gov (United States)

Bouaziz, Fatma; Koubaa, Mohamed; Kallel, Fatma; Ghorbel, Rhoudha Ellouz; Chaabouni, Semia Ellouz

2017-12-01

This work aimed at investigating the potential of almond gum as low cost adsorbent for the removal of the cationic dye; malachite green from aqueous solutions. Almond gum was first analyzed by scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR), and then the adsorption behavior was studied in batch system. The effects of the adsorption parameters (adsorbent dose, pH, contact time, particle size, initial dye concentration, temperature and agitation) on the dye removal have been studied. Adsorption equilibrium and isotherms were evaluated depending on temperature using the isotherms of Freundlich, Langmuir, and Tempkin. The obtained result showed that both Langmuir and Freundlich models were adapted to study the dye sorption. The maximum adsorption capacities were equal to 172.41mg/g, 181.81mg/g, and 196.07mg/g at 303.16K, 313.16K, and 323.16K, respectively. The kinetics of sorption were following the pseudo-second order model. The thermodynamic changes in enthalpy (ΔH), entropy (ΔS), and free energy (ΔG) indicated that the adsorption of malachite green at the surface of almond gum is endothermic and occurs spontaneously. Desorption experiments were conducted to regenerate almond gum, showing great desorption capacity when using HCl at pH 2. Copyright © 2017 Elsevier B.V. All rights reserved.

Tetrazolium Reduction-Malachite Green Method for Assessing the Viability of Filamentous Bacteria in Activated Sludge

Science.gov (United States)

Bitton, Gabriel; Koopman, Ben

1982-01-01

A method was developed to assess the activity of filamentous bacteria in activated sludge. It involves the incubation of activated sludge with 2(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride followed by staining with malachite green. Both cells and 2(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride-formazan crystals can be observed in prepared specimens by using bright-field microscopy. This procedure allowed us to distinguish between inactive and actively metabolizing filaments after chlorine application to control the bulking of activated sludge. Images PMID:16345999

Removal of Malachite Green dye from aqueous solution using MnFe2O4/Al2O3 Nanophotocatalyst by UV/H2O2 process

Directory of Open Access Journals (Sweden)

Davood Kaviani

2016-04-01

Full Text Available Background & Aims of the Study: Malachite Green (MG is the most commonly used substance for dying cotton, food & pharmacy industries, paper, leather and silk. On inhalation it can cause difficult breathing, while on the direct contact it may cause permanent injury of the eyes of human and animals, burning sensations, nausea, vomiting, profuse sweating, mental confusion and methemoglobinemia; also it can causes cancer in livers. The aim of this study is  the removal of Malachite Green (MG dye from aqueous solutions, using MnFe2O4/Al2O3 nanophotocatalyst by UV/H2O2 process which was used as a low cost method. Materials & Methods: In this research, photocatalytic decomposition of malachite green in water was done by nanocatalyst MnFe2O4/Al2O3 in discontinuous photoreactor under UV light and the injection of H2O2. In order to identify and analyze the provided catalyst, SEM image and XRD diffraction pattern were used. The effect of operational factors in the photocatalytic decomposition of the desired pollutant such as pH, the initial thickness of the dye, the thickness of H2O2 and the quantity of the catalyst were investigated. Results: The finding showed that the right conditions for the elimination of the pollutant included pH equals 4, the initial thickness of the dye being 10 ppm, the thickness of H2O2 being 250ppm, the amount of catalyst being 50mg, the Correlation Coefficient being 0.998 and the dye removal was 94 percent at the end of the experiment. the reaction of Malachite green decomposition was in terms of kinetics investigated through integral method as well; also it showed the kinetic reaction is the first type and the constant speed rate is K=0.047 min-1 . Conclusions: According to the results, because of the complexity of dye structure, biological system was not able to remove the dye as efficient as hybrid system of advanced oxidation processes UV/H2O2 with nanophotocatalyst as an efficient way to remove the Malachite green dye

Determination of malachite green in aquatic products based on magnetic molecularly imprinted polymers.

Science.gov (United States)

Lin, Zheng-zhong; Zhang, Hong-yuan; Peng, Ai-hong; Lin, Yi-dong; Li, Lu; Huang, Zhi-yong

2016-06-01

Magnetic molecularly imprinted polymers (MMIPs) were synthesized through precipitation polymerization using malachite green (MG) as template, methacrylic acid as monomer, ethylene dimethacrylate as crosslinker, and Fe3O4 magnetite as magnetic component. MMIPs were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, and vibrating sample magnetometry. Under the optimum condition, the MMIPs obtained exhibited quick binding kinetics and high affinity to MG in the solution. Scatchard plot analysis revealed that the MMIPs contained only one type of binding site with dissociation constant of 24.0 μg mL(-1). The selectivity experiment confirmed that the MMIPs exhibited higher selective binding capacity for MG than its structurally related compound (e.g., crystal violet). As a sorbent for the extraction of MG in sample preparation, MMIPs together with the absorbed analytes could easily be separated from the sample matrix with an external magnet. After elution with methanol/acetic acid (9:1, v/v), MG in the eluent was determined by high-performance liquid chromatography coupled with UV detector with recoveries of 94.0-115%. Results indicated that the as-prepared MMIPs are promising materials for MG analysis in aquatic products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thermodynamics of Ligand Binding to a Heterogeneous RNA Population in the Malachite Green Aptamer

Science.gov (United States)

Sokoloski, Joshua E.; Dombrowski, Sarah E.; Bevilacqua, Philip C.

2011-01-01

The malachite green aptamer binds two closely related ligands, malachite green (MG) and tetramethylrosamine (TMR), with near equal affinity. The MG ligand consists of three phenyl rings emanating from a central carbon, while TMR has two of the three rings connected by an ether linkage. The binding pockets for MG and TMR in the aptamer, known from high-resolution structure, differ only in the conformation of a few nucleotides. Herein, we applied isothermal titration calorimetry (ITC) to compare the thermodynamics for binding of MG and TMR to the aptamer. Binding heat capacities were obtained from ITC titrations over the temperature range of 15 to 60 °C. Two temperature regimes were found for MG binding: one from 15 to 45 °C where MG bound with a large negative heat capacity and an apparent stoichiometry (n) of ~0.4, and another from 50 to 60 °C where MG bound with positive heat capacity and n~1.1. The binding of TMR, on the other hand, revealed only one temperature regime for binding, with a more modest negative heat capacity and n~1.2. The large difference in heat capacity between the two ligands suggests that significantly more conformational rearrangement occurs upon the binding of MG than TMR, which is consistent with differences in solvent accessible surface area calculated for available ligand-bound structures. Lastly, we note that binding stoichiometry of MG was improved not only by raising the temperature, but also by lowering the concentration of Mg2+ or increasing the time between ITC injections. These studies suggest that binding of a dynamical ligand to a functional RNA requires the RNA itself to have significant dynamics. PMID:22192051

Remarkable photo-catalytic degradation of malachite green by nickel doped bismuth selenide under visible light irradiation

International Nuclear Information System (INIS)

Kulsi, Chiranjit; Ghosh, Amrita; Mondal, Anup; Kargupta, Kajari; Ganguly, Saibal; Banerjee, Dipali

2017-01-01

Highlights: • Bi_2Se_3 and Ni doped Bi_2Se_3 were synthesized by solvothermal approach. • Presence of nickel was confirmed by X-ray photoelectron spectroscopy (XPS) measurement. • Complete degradation of malachite green (MG) dye was achieved by Ni doped Bi_2Se_3 with H_2O_2. • Remarkable photo-catalytic degradation by doped bismuth selenide has been explained. • Scavenger tests show degradation of MG is mainly dominated by ·OH oxidation process. - Abstract: Bismuth selenide (Bi_2Se_3) and nickel (Ni) doped Bi_2Se_3 were prepared by a solvothermal approach to explore the photo-catalytic performance of the materials in degradation of malachite green (MG). The presence of nickel was confirmed by X-ray photoelectron spectroscopy (XPS) measurement in doped Bi_2Se_3. The results showed that the nickel doping played an important role in microstructure and photo-catalytic activity of the samples. Nickel doped Bi_2Se_3 sample exhibited higher photo-catalytic activity than that of the pure Bi_2Se_3 sample under visible-light irradiation. The photo-catalytic degradation followed first-order reaction kinetics. Fast degradation kinetics and complete (100% in 5 min of visible light irradiation) removal of MG was achieved by nickel doped Bi_2Se_3 in presence of hydrogen peroxide (H_2O_2) due to modification of band gap energies leading to suppression of photo-generated electron-hole recombination.

Degradation of malachite green on Pd/WO3 photocatalysts under simulated solar light

International Nuclear Information System (INIS)

Liu Yonggang; Ohko, Yoshihisa; Zhang Ruiqin; YangYingnan; Zhang Zhenya

2010-01-01

The photocatalytic degradation of malachite green (MG) dye molecules in aqueous solution was investigated by using palladium (Pd) modified tungsten trioxide (WO 3 ) under simulated solar light. The optimum values for Pd content vs. WO 3 and catalyst concentration in solution for MG (5.0 μmol L -1 ) degradation were 0.5 wt.% and 150 mg L -1 , respectively. The MG concentration change followed the pseudo first order kinetics of the Langmuir-Hinshelwood model. Since MG was also degraded under visible light (λ > 470 nm), which was not absorbed by WO 3 , the mechanism involved both the photocatalytic degradation and self-sensitized degradation of MG. Pd modified WO 3 would be useful as an efficient tool for the decolorization of wastewater under solar light.

Pulse radiolysis of malachite green leucocyanide in alcoholic solvents, the influence of oxygen

International Nuclear Information System (INIS)

Grodkowski, J.; Stuglik, Z.; Wieczorek, G.

1992-01-01

The solutions of malachite green leucocyanide (MGCN) in methanol, n-propanol and 2-propanol were investigated using pulse radiolysis. In the presence of oxygen, MG + -carbonium ions were radiolytically formed in two different time steps. The yield of MG + in the slower process was dependent on oxygen concentration and was proportional to the yield of intermediate MG radicals. The yield of MG was about ten times higher in 2-propanol than in methanol and n-propanol solutions. The reactants responsible for MG oxidation to MG + were RO 2 , hydroxyalkylperoxyl radicals derived from alcohols. The rate constant for MG reaction with RO 2 were estimated as (6.5±1) x 10 8 M -1 s -1 . The molar extinction coefficient of MG was calculated. (author)

Use of Enzymatic Bio-Fenton as a New Approach in Decolorization of Malachite Green

Science.gov (United States)

Karimi, Afzal; Aghbolaghy, Mostafa; Khataee, Alireza; Shoa Bargh, Shabnam

2012-01-01

An enzymatic reaction using glucose oxidase was applied for in situ production of hydrogen peroxide for use in simultaneously Fenton's reaction in decolorization of malachite green. It was found that decolorization rate increased by increasing of glucose concentration from 0.2 g/L to 1.5 g/L. Decolorization rate showed different behaviors versus temperature changes. Initial rate of decolorization process was increased by increasing of temperature; after 30 minutes, especially at temperatures above 30°C, the decolorization rate was gradually reduced. The pH value in the reaction media was decreased from natural to about pH = 3 which had synergic effect on the Fenton process by stabilizing of Fe2+ ions. PMID:22649310

Removal of Malachite Green from aqueous solution using degreased coffee bean

International Nuclear Information System (INIS)

Baek, Mi-Hwa; Ijagbemi, Christianah Olakitan; O, Se-Jin; Kim, Dong-Su

2010-01-01

This study reports on the feasibility of employing degreased coffee beans (DCB) as adsorbent for Malachite Green (MG) removal in dyeing wastewater. The iodine value (IV), specific surface area (SSA) and porosity of the raw coffee beans (RCB) used in the study increased after the degreasing process, resulting in significant increase in the adsorption of MG onto DCB. Employing a batch experimental set-up, optimum conditions for complete color removal and adsorption of MG by DCB was studied considering parameters such as effect of degreasing process, adsorbent dosage, initial dye concentration, reaction temperature and pH. Adsorbed amount of MG by DCB increased with increasing DCB dosage and initial MG concentration. The rate of the adsorption reaction followed the pseudo second-order kinetics with the sorption isotherm well fitted to the Freundlich and the Langmuir isotherm models. Thermodynamic studies revealed that the adsorption processes is spontaneous and endothermic in nature. DCB has potentials for application as adsorbent for the removal of MG from dyeing process wastewater.

Removal of Malachite Green from aqueous solution using degreased coffee bean

Energy Technology Data Exchange (ETDEWEB)

Baek, Mi-Hwa; Ijagbemi, Christianah Olakitan; O, Se-Jin [Department of Environmental Science and Engineering, Ewha Womans University, Daehyundong 11-1, Seodaemungu, Seoul 120-750 (Korea, Republic of); Kim, Dong-Su, E-mail: dongsu@ewha.ac.kr [Department of Environmental Science and Engineering, Ewha Womans University, Daehyundong 11-1, Seodaemungu, Seoul 120-750 (Korea, Republic of)

2010-04-15

This study reports on the feasibility of employing degreased coffee beans (DCB) as adsorbent for Malachite Green (MG) removal in dyeing wastewater. The iodine value (IV), specific surface area (SSA) and porosity of the raw coffee beans (RCB) used in the study increased after the degreasing process, resulting in significant increase in the adsorption of MG onto DCB. Employing a batch experimental set-up, optimum conditions for complete color removal and adsorption of MG by DCB was studied considering parameters such as effect of degreasing process, adsorbent dosage, initial dye concentration, reaction temperature and pH. Adsorbed amount of MG by DCB increased with increasing DCB dosage and initial MG concentration. The rate of the adsorption reaction followed the pseudo second-order kinetics with the sorption isotherm well fitted to the Freundlich and the Langmuir isotherm models. Thermodynamic studies revealed that the adsorption processes is spontaneous and endothermic in nature. DCB has potentials for application as adsorbent for the removal of MG from dyeing process wastewater.

Efficient photo-catalytic degradation of malachite green using nickel tungstate material as photo-catalyst.

Science.gov (United States)

Helaïli, N; Boudjamaa, A; Kebir, M; Bachari, K

2017-03-01

The present study focused on the evaluation of photo-catalytic and photo-electrochemical properties of the photo-catalyst based on nickel tungstate material prepared by a nitrate method through the degradation of malachite green (MG) dye's. The effect of catalyst loading and dye concentration was examined. Physico-chemical, optical, electrical, electrochemical, and photo-electrochemical properties of the prepared material were analyzed by X-ray diffraction (XRD), fourier transform-infrared spectroscopy (FTIR), BET analysis, optical reflectance diffuse (DR), scanning electron microscopy (SEM/EDX), electrical conductivity, cyclic voltammetry (CV), current intensity, mott-shottky, and nyquist. XRD revealed the formation of monoclinic structure with a small particle size. BET surface area of the sample was around 10 m 2 /g. The results show that the degradation of MG was more than 80%, achieved after 3 h of irradiation at pH 4.6 and with a catalyst loading of 75 mg. Also, it was found that the dye photo-degradation obeyed the pseudo-first order kinetic via Langmuir Hinshelwood model.

Pulse radiolysis of malachite green leucocyanide in alcoholic solvents, the influence of oxygen

Energy Technology Data Exchange (ETDEWEB)

Grodkowski, J; Stuglik, Z; Wieczorek, G [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

1992-04-01

The solutions of malachite green leucocyanide (MGCN) in methanol, n-propanol and 2-propanol were investigated using pulse radiolysis. In the presence of oxygen, MG{sup +}-carbonium ions were radiolytically formed in two different time steps. The yield of MG{sup +} in the slower process was dependent on oxygen concentration and was proportional to the yield of intermediate MG radicals. The yield of MG was about ten times higher in 2-propanol than in methanol and n-propanol solutions. The reactants responsible for MG oxidation to MG{sup +} were RO{sub 2}, hydroxyalkylperoxyl radicals derived from alcohols. The rate constant for MG reaction with RO{sub 2} were estimated as (6.5{+-}1) x 10{sup 8}M{sup -1}s{sup -1}. The molar extinction coefficient of MG was calculated. (author).

Malachite green "a cationic dye" and its removal from aqueous solution by adsorption

Science.gov (United States)

Raval, Nirav P.; Shah, Prapti U.; Shah, Nisha K.

2017-11-01

Adsorption can be efficiently employed for the removal of various toxic dyes from water and wastewater. In this article, the authors reviewed variety of adsorbents used by various researchers for the removal of malachite green (MG) dye from an aqueous environment. The main motto of this review article was to assemble the scattered available information of adsorbents used for the removal of MG to enlighten their wide potential. In addition to this, various optimal experimental conditions (solution pH, equilibrium contact time, amount of adsorbent and temperature) as well as adsorption isotherms, kinetics and thermodynamics data of different adsorbents towards MG were also analyzed and tabulated. Finally, it was concluded that the agricultural solid wastes and biosorbents such as biopolymers and biomass adsorbents have demonstrated outstanding adsorption capabilities for removal of MG dye.

Decolorization of malachite green, decolorization kinetics and stoichiometry of ozone-malachite green and removal of antibacterial activity with ozonation processes

International Nuclear Information System (INIS)

Kusvuran, Erdal; Gulnaz, Osman; Samil, Ali; Yildirim, Ozlem

2011-01-01

This study aimed to identify degradation intermediates and to investigate the stoichiometry of decolorization and degradation, decolorization kinetics, and removal of antibacterial activity of malachite green (MG) using ozonization processes. The decolorization of MG was optimal at an acidic pH value of 3 based on molecular ozone attack on MG molecules. The stoichiometric ratio of decolorization between ozone and MG was calculated to be 7.0 with a regression coefficient of 0.995, whereas the ratio for degradation was calculated as 13.1 with a regression coefficient of 0.998. With MG concentrations in the range of 0.30-1.82 mM, the concentration of decolorized MG increased with higher initial concentrations of MG, whereas the ozonolytic decolorization rates of MG, decreased with increasing initial concentration. The pseudo-first-order degradation rate constants (k') decreased with the initial concentration and ranged from 0.769 to 0.223 min -1 . Twelve different intermediates were produced during the ozonation of MG with ozonation times between 5 min and 30 min and were identified by GC-MS. Although 86% of MG in the reaction mixture was removed by ozonation after 10 min, the decrease of antibacterial activity was very low (10%) for Bacillus subtilis and Staphylococcus epidermidis because the degradation intermediates, phenol and benzoic acid, also have antibacterial activity. The antibacterial activity of both MG and its intermediates were removed successfully with ozonation times above 26 min.

Decolorization of malachite green, decolorization kinetics and stoichiometry of ozone-malachite green and removal of antibacterial activity with ozonation processes

Energy Technology Data Exchange (ETDEWEB)

Kusvuran, Erdal, E-mail: erdalkusvuran@yahoo.com [Chemistry Department, Arts and Sciences Faculty, Cukurova University, 01330 Balcali, Adana (Turkey); Gulnaz, Osman [Biology Department, Arts and Sciences Faculty, Cukurova University, 01330 Balcali, Adana (Turkey); Samil, Ali [Chemistry Department, Arts and Sciences Faculty, Sutcu Imam University, 46100 Kahramanmaras (Turkey); Yildirim, Ozlem [Chemistry Department, Arts and Sciences Faculty, Cukurova University, 01330 Balcali, Adana (Turkey)

2011-02-15

This study aimed to identify degradation intermediates and to investigate the stoichiometry of decolorization and degradation, decolorization kinetics, and removal of antibacterial activity of malachite green (MG) using ozonization processes. The decolorization of MG was optimal at an acidic pH value of 3 based on molecular ozone attack on MG molecules. The stoichiometric ratio of decolorization between ozone and MG was calculated to be 7.0 with a regression coefficient of 0.995, whereas the ratio for degradation was calculated as 13.1 with a regression coefficient of 0.998. With MG concentrations in the range of 0.30-1.82 mM, the concentration of decolorized MG increased with higher initial concentrations of MG, whereas the ozonolytic decolorization rates of MG, decreased with increasing initial concentration. The pseudo-first-order degradation rate constants (k') decreased with the initial concentration and ranged from 0.769 to 0.223 min{sup -1}. Twelve different intermediates were produced during the ozonation of MG with ozonation times between 5 min and 30 min and were identified by GC-MS. Although 86% of MG in the reaction mixture was removed by ozonation after 10 min, the decrease of antibacterial activity was very low (10%) for Bacillus subtilis and Staphylococcus epidermidis because the degradation intermediates, phenol and benzoic acid, also have antibacterial activity. The antibacterial activity of both MG and its intermediates were removed successfully with ozonation times above 26 min.

Use of Enzymatic Bio-Fenton as a New Approach in Decolorization of Malachite Green

Directory of Open Access Journals (Sweden)

Afzal Karimi

2012-01-01

Full Text Available An enzymatic reaction using glucose oxidase was applied for in situ production of hydrogen peroxide for use in simultaneously Fenton's reaction in decolorization of malachite green. It was found that decolorization rate increased by increasing of glucose concentration from 0.2 g/L to 1.5 g/L. Decolorization rate showed different behaviors versus temperature changes. Initial rate of decolorization process was increased by increasing of temperature; after 30 minutes, especially at temperatures above 30°C, the decolorization rate was gradually reduced. The pH value in the reaction media was decreased from natural to about pH=3 which had synergic effect on the Fenton process by stabilizing of Fe2+ ions.

Diphenylmethyl selenocyanate attenuates malachite green induced oxidative injury through antioxidation & inhibition of DNA damage in mice

Science.gov (United States)

Das, Jayanta Kumar; Sarkar, Sibani; Hossain, Sk Ugir; Chakraborty, Pramita; Das, Rajat Kumar; Bhattacharya, Sudin

2013-01-01

Background & objectives: Malachite green (MG), an environmentally hazardous material, is used as a non permitted food colouring agent, especially in India. Selenium (Se) is an essential nutritional trace element required for animals and humans to guard against oxidative stress induced by xenobiotic compounds of diverse nature. In the present study, the role of the selenium compound diphenylmethyl selenocyanate (DMSE) was assessed on the oxidative stress (OS) induced by a food colouring agent, malachite green (MG) in vivo in mice. Methods: Swiss albino mice (Mus musculus) were intraperitoneally injected with MG at a standardized dose of 100 μg/ mouse for 30 days. DMSE was given orally at an optimum dose of 3 mg/kg b.w. in pre (15 days) and concomitant treatment schedule throughout the experimental period. The parameters viz. ALT, AST, LPO, GSH, GST, SOD, CAT, GPx, TrxR, CA, MN, MI and DNA damage have been evaluated. Results: The DMSE showed its potential to protect against MG induced hepatotoxicity by controlling the serum alanine aminotransferase and aspartate amino transferase (ALT and AST) levels and also ameliorated oxidative stress by modulating hepatic lipid peroxidation and different detoxifying and antioxidative enzymes such as glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), and also the selenoenzymes such as glutathione peroxidase (GPx) and thioredoxin reductase (TrxR) and reduced glutathione level which in turn reduced DNA damage. Interpretation & conclusions: The organo-selenium compound DMSE showed significant protection against MG induced heptotoxicity and DNA damage in murine model. Better protection was observed in pretreatment group than in the concomitant group. Further studies need to be done to understand the mechanism of action. PMID:23852297

Novel treatment using topical malachite green for nasal phaeohyphomycosis caused by a new Cladophialophora species in a cat.

Science.gov (United States)

Brooks, Ian J; Walton, Stuart A; Shmalberg, Justin; Harris, Autumn

2018-01-01

A 1.5-year-old castrated male domestic shorthair cat presented with a 2 month history of progressive nasal swelling and hyporexia. Minimal improvement prior to referral was achieved with a course of antibiotics and glucocorticoids. Cytology of an ulcerative lesion on the dorsal aspect of the nose was consistent with a diagnosis of phaeohyphomycosis. The cat achieved static disease for 6 weeks following initiation of itraconazole but developed epistaxis at 9 weeks. CT of the head demonstrated nasal and frontal sinus involvement. Nasal biopsy and culture identified infection with a Cladophialophora species not previously reported to cause disease. Initial response to a combination of itraconazole and terbinafine was noted, but owing to severe thrombocytopenia this combination was discontinued. Voriconazole was used but discontinued because of adverse side effects. Posaconazole treatment was offered throughout the clinical course but rejected owing to financial constraints and an uncertain response to medical therapy. Rhinotomy with debulking of diseased tissue and topical malachite green treatment was performed. Following the procedure itraconazole was continued and the cat has had no recurrence for over 1 year. Infections by Cladophialophora species have been reported in veterinary species, including cats. The specific fungal organism isolated from this cat has not been previously reported to cause disease in humans or animals and has only been described in the mangroves of Brazil. Furthermore, this is the first report to describe the use of topical malachite green as a treatment for refractory phaeohyphomycosis.

Determination of trace amount of formaldehyde base on a bromate-Malachite Green system.

Science.gov (United States)

Tang, Yufang; Chen, Hao; Weng, Chao; Tang, Xiaohui; Zhang, Miaoling; Hu, Tao

2015-01-25

A novel catalytic kinetic spectrophotometric method for determination of trace amount of formaldehyde (FA) has been established, based on catalytic effect of trace amount of FA on the oxidation of Malachite Green (MG) by potassium bromate in presence of sulfuric acid medium, and was reported for the first time. The method was monitored by measuring the decrease in absorbance of MG at 617 nm and allowed a precise determination of FA in the range of 0.003-0.08 μg mL(-1), with a limit of detection down to 1 ng mL(-1). The relative standard deviation of 10 replicate measurements was 1.63%. The method developed was approved to be sensitive, selective and accurate, and adopted to determinate free FA in samples directly with good accuracy and reproducibility. Copyright © 2014 Elsevier B.V. All rights reserved.

The effect of gamma irradiation on chitosan film dyed with malachite green

International Nuclear Information System (INIS)

Yeoh Siong Hu; Md Soot Ahmad

2009-01-01

In this research, chitosan is used as the base for a dye and the effects of γ-irradiation on the dye was researched. The dyed chitosan film of the thickness 70 μm was developed by dissolving chitosan powder in an acetic acid solution. Malachite Green dye was used as the dye and was prepared by using water as solvent. Dyed chitosan gel was the dried and small pieces of 1 x 1 cm 2 was cut out and the dyed film was analyzed using the UV-VIS spectrometer and achieved a maximum absorption at the wavelength of λ=615 nm. Using Gammacell, the film was irradiated by gamma ray with various doses ranging from 5-25 KGy. The effect of the irradiation on the dyed film was study for various factors. The effect of the dose, thickness and shelf life was studied and shows significant effect to the optical density. As the dose reaches 25 KGy, the destruction of the dye approaches 20%. (Author)

Biomimetic ELISA detection of malachite green based on molecularly imprinted polymer film.

Science.gov (United States)

Li, Lu; Peng, Ai-Hong; Lin, Zheng-Zhong; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

2017-08-15

A highly selective and sensitive enzyme-linked immunosorbent assay (ELISA) was developed for the detection of malachite green (MG) using a molecularly imprinted polymer (MIP) film as bionic antibody. The MIP film, based on the self-polymerization of dopamine, was fabricated on the surfaces of a 96-well microplate. It showed specific recognition for MG in aqueous solution. A direct competitive ELISA method was established with the sensitivity reaching 10.31μgL -1 and the detection limit being 0.3μgL -1 . The cross-reactivity of two structural analogues to MG was less than 10%. The average recovery tested by MG standard spiking was 88.8% for bass and 90.4% for water, and the relative standard deviations were less than 3.6%. All the above results indicated that the developed method could be used to detect MG in fish and water samples rapidly, specifically and accurately. Copyright © 2017 Elsevier Ltd. All rights reserved.

Removal of Malachite Green from aqueous solution using degreased coffee bean.

Science.gov (United States)

Baek, Mi-Hwa; Ijagbemi, Christianah Olakitan; O, Se-Jin; Kim, Dong-Su

2010-04-15

This study reports on the feasibility of employing degreased coffee beans (DCB) as adsorbent for Malachite Green (MG) removal in dyeing wastewater. The iodine value (IV), specific surface area (SSA) and porosity of the raw coffee beans (RCB) used in the study increased after the degreasing process, resulting in significant increase in the adsorption of MG onto DCB. Employing a batch experimental set-up, optimum conditions for complete color removal and adsorption of MG by DCB was studied considering parameters such as effect of degreasing process, adsorbent dosage, initial dye concentration, reaction temperature and pH. Adsorbed amount of MG by DCB increased with increasing DCB dosage and initial MG concentration. The rate of the adsorption reaction followed the pseudo second-order kinetics with the sorption isotherm well fitted to the Freundlich and the Langmuir isotherm models. Thermodynamic studies revealed that the adsorption processes is spontaneous and endothermic in nature. DCB has potentials for application as adsorbent for the removal of MG from dyeing process wastewater. 2009 Elsevier B.V. All rights reserved.

Removal of malachite green by using an invasive marine alga Caulerpa racemosa var. cylindracea

International Nuclear Information System (INIS)

Bekci, Zehra; Seki, Yoldas; Cavas, Levent

2009-01-01

The biosorption of a cationic dye, malachite green oxalate (MG) from aqueous solution onto an invasive marine alga Caulerpa racemosa var. cylindracea (CRC) was investigated at different temperatures (298, 308 and 318 K). The dye adsorption onto CRC was confirmed by FTIR analysis. Equilibrium data were analyzed using Freundlich, Langmuir and Dubinin-Radushkevich (DR) equations. All of the isotherm parameters were calculated. The Freundlich model gave a better conformity than Langmuir equation. The mean free energy values (E) from DR isotherm were also estimated. In order to clarify the sorption kinetic, the fit of pseudo-first-order kinetic model, second-order kinetic model and intraparticle diffusion model were investigated. It was obtained that the biosorption process followed the pseudo-second-order rate kinetics. From thermodynamic studies the free energy changes were found to be -7.078, -9.848 and -10.864 kJ mol -1 for 298, 308 and 318 K, respectively. This implied the spontaneous nature of biosorption and the type of adsorption as physisorption. Activation energy value for MG sorption (E a ) was found to be 37.14 kJ mol -1 . It could be also derived that this result supported physisorption as a type of adsorption

Malachite green and chloramphenicol in aquatic products from regions around Dongting Lake in Hunan, China.

Science.gov (United States)

He, Jiang; Cui, Jingzhen

2016-01-01

Aquatic products are important sources of animal proteins in human diet, especially in developing countries. As such, the safety of aquatic products is of primary concern. In this study, a standard method is used to detect malachite green (MG) and chloramphenicol (CAP) and to analyse the contents of these banned chemicals in turtle, mandarin fish and grass carp sampled from the region surrounding Dongting Lake area in Hunan, China. Results showed that 10.6% of the samples were MG-positive, most of them turtles. CAP was found in 8.3% of the samples, mostly in mandarin fish. These data indicated that these banned substances are still used in the surveyed area. Hence, adequate strategies must be implemented by the local government to control these banned substances.

Adsorption of malachite green by magnetic litchi pericarps: A response surface methodology investigation.

Science.gov (United States)

Zheng, Hao; Qi, Jinqiu; Jiang, Ruixue; Gao, Yan; Li, Xiaochen

2015-10-01

In this work, we synthesized a novel magnetic adsorbent containing litchi pericarps, denoted as MLP, for the removal of malachite green (MG) from solution. The factors influencing MG adsorption, such as contact time, adsorbent dosage, and initial dye concentration, were optimized using the Box-Behnken response surface methodology (RSM). The adsorption isotherms as well as the kinetics and thermodynamics of the adsorption of MG onto MLP are discussed. The results showed that MLP has a maximum adsorption efficiency of 99.5% when the temperature, pH, contact time, adsorbent dosage, and initial MG concentration were optimally set as 25 °C, 6.0, 66.69 min, 5.14 g/L, and 150 mg/L, respectively. The best model to describe this process is the Langmuir isotherm, with the maximum adsorption capacity being 70.42 mg/g. In addition, the kinetics of MG adsorption onto MLP followed a pseudo-second-order model; moreover, thermodynamic analysis suggested that MG adsorption onto MLP is spontaneous and endothermic. Finally, it was found that the new magnetic adsorbent can be separated easily and rapidly from mixed solutions in the presence of an external magnetic field. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enhanced sulfidation xanthate flotation of malachite using ammonium ions as activator.

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Wu, Dandan; Ma, Wenhui; Mao, Yingbo; Deng, Jiushuai; Wen, Shuming

2017-05-18

In this study, ammonium ion was used to enhance the sulfidation flotation of malachite. The effect of ammonium ion on the sulfidation flotation of malachite was investigated using microflotation test, inductively coupled plasma (ICP) analysis, zeta potential measurements, and scanning electron microscope analysis (SEM). The results of microflotation test show that the addition of sodium sulfide and ammonium sulfate resulted in better sulfidation than the addition of sodium sulfide alone. The results of ICP analysis indicate that the dissolution of enhanced sulfurized malachite surface is significantly decreased. Zeta potential measurements indicate that a smaller isoelectric point value and a large number of copper-sulfide films formed on the malachite surface by enhancing sulfidation resulted in a large amount of sodium butyl xanthate absorbed onto the enhanced sulfurized malachite surface. EDS semi-quantitative analysis and XPS analysis show that malachite was easily sulfurized by sodium sulfide with ammonium ion. These results show that the addition of ammonium ion plays a significant role in the sulfidation of malachite and results in improved flotation performance.

Comparative analysis and validation of the malachite green assay for the high throughput biochemical characterization of terpene synthases.

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Vardakou, Maria; Salmon, Melissa; Faraldos, Juan A; O'Maille, Paul E

2014-01-01

Terpenes are the largest group of natural products with important and diverse biological roles, while of tremendous economic value as fragrances, flavours and pharmaceutical agents. Class-I terpene synthases (TPSs), the dominant type of TPS enzymes, catalyze the conversion of prenyl diphosphates to often structurally diverse bioactive terpene hydrocarbons, and inorganic pyrophosphate (PPi). To measure their kinetic properties, current bio-analytical methods typically rely on the direct detection of hydrocarbon products by radioactivity measurements or gas chromatography-mass spectrometry (GC-MS). In this study we employed an established, rapid colorimetric assay, the pyrophosphate/malachite green assay (MG), as an alternative means for the biochemical characterization of class I TPSs activity.•We describe the adaptation of the MG assay for turnover and catalytic efficiency measurements of TPSs.•We validate the method by direct comparison with established assays. The agreement of k cat/K M among methods makes this adaptation optimal for rapid evaluation of TPSs.•We demonstrate the application of the MG assay for the high-throughput screening of TPS gene libraries.

Removal of malachite green from aqueous solution by activated carbon prepared from the Annona squmosa seed by adsorption

Directory of Open Access Journals (Sweden)

T. Santhi

2010-12-01

Full Text Available The use of low -cost, locally available, highly efficient and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbon prepared from the Annona squmosa seed for the removal of malachite green (MG dye from simulated wastewater. The effects of different system variables, adsorbent dosage, initial dye concentration, pH and contact time were investigated and optimal experimental conditions were ascertained. The results showed that as the amount of the adsorbent is increased, the percentage of dye removal increase accordingly. Optimum pH value for dye adsorption was 7.0. Maximum dye was sequestered within 50 min from the start of every experiment. The adsorption of malachite green followed the pseudo-second –order rate equation and fits the Langmuir, Freundlich, Dubinin-Radushekevich (D-R and Tempkin equations well. The maximum removal of MG was obtained at pH 7 as 86.11% for adsorbent dose of 0.2 g/ 50 mL and 25 mg L -1 initial dye concentration at room temperature. Furthermore, adsorption kinetics of MG was studied and the rate of adsorption was found to conform to pseudo-second –order kinetics with a good correlation (R2 > 0.99 with intraparticle diffusion as one of the rate determining steps. Activated carbon developed from the Annona squmosa seed can be an attractive option for dye removal from diluted industrial effluents since test reaction made on simulated dyeing wastewater showed better removal percentage of MG.

Acceleration effect of alcohols on ion association of molbdophosphate with malachite green and its use to the sensitive flow-injection determination of phosphate. Molybdo rinsan ion-malachite green ion kaigotai seisei ni oyobosu alcohol no hanno sokushinkoka to sore wo riyosuru rin no kokando flow injection bunseki

Energy Technology Data Exchange (ETDEWEB)

Motomizu, S; Yasuda, Y; Oshima, M [Okayama Univ., Okayama (Japan). Faculty of Science

1991-12-10

Molibdophosphoric acid (PMo) reacts with malachite green (MG{sup +}) to form a colored ion associate (MG{sup +}- PMo) in an acidic solution according to the formula : HMG{sup 2+}+H{sub 3}PMo{sub 12}O{sub 40}{yields}(MG{sup +})H{sub 2}PMo{sub 12}O{sub 40}+2H{sup +}. A protonated form HMG{sup 2+} is yellow (the absorption mximum at 446 nm), whereas the ion associate MG{sup +} is blue green (the absorption maximum at 650 nm). MG{sup +} is found to accelerate the formation of PMo. Water-miscible organic solvents such as methanol,ethanol and propanol also accelerate the formation of PMo as well as the formation of MG sup + - PMo. Some anionic surfactants decelerate the reaction, however, contribute to the suppression of the baseline drift in a flow injection analysis (FIA). By the use of the proposed reaction accelerator and surfactant. a highly sensitive FIA system is established for,orthophosphate up to the range of several ppb. 16 figs.. 11 refs.

Inorganic fullerene-type WS2 nanoparticles: processing, characterization and its photocatalytic performance on malachite green

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Hazarika, Saurabh Jyoti; Mohanta, Dambarudhar

2017-05-01

In this work, we have employed a hydrothermal route for the synthesis of fullerene-type tungsten disulfide (WS2) nanoparticles. X-ray diffraction analysis signifies a hexagonal crystal structure of WS2 with the crystallites experiencing preferred orientations along (002) and (103) planes. The agglomerated nanoparticles and inorganic fullerene (IF)-type structures are apparently observable from the high-resolution electron micrographs. Raman spectrum shows prominent E1_{{2{{g}}}} and A 1g modes emanating from the IF nano-WS2 system. The Tauc's plot obtained from the optical absorption data predicts a direct band gap of 1.91 eV for the nano-WS2 system; whereas, photoluminescence analysis reveals a broad emission peak located at 638 nm and is ascribed to the associated transition from the indirect to direct nature of the band gap. The photocatalytic decomposition of malachite green (MG) solution (30 mg/l) by WS2 (100 mg/l) under UV and visible light irradiation has been evaluated. The latter condition exhibited a better photocatalytic response with the MG degradation as high as 71.2%, revealed for 120 min. Photocatalytic and optoelectronic features of IF-type nano-WS2 would bring new insights not only to resolve issues related to environmental hazards, but also in functional devices of technological relevance.

Effective adsorption of malachite green using magnetic barium phosphate composite from aqueous solution

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Zhang, Fan; Wei, Zhong; Zhang, Wanning; Cui, Haiyan

2017-07-01

Magnetic Ba3(PO4)2/Fe3O4-nanoparticle (called BPFN) was prepared, characterized, and developed as a low-cost adsorbent for malachite green (MG) from aqueous solution. Factors such as adsorption temperature, pH of solution, dosage of adsorbent, adsorption kinetics and isotherms were investigated. The maximum adsorption capacity obtained in this work was 1639 mg g- 1 at 45 °C and pH 6. The adsorption process fitted the pseudo-first-order kinetic model and Langmuir isotherm model. Evidences from zeta potential, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) data revealed that the adsorption process was driven by electrostatic attraction, the interaction between Lewis base sbnd N(CH3)2 in MG and Lewis acid Ba sites of BPFN. In addition, the BPFN could be easily regenerated by a magnet and the adsorption capacity maintained at 70% after five cycles. The present study suggests that the BPFN had high potential of removing MG from wastewater.

Heterologous Expression of Phanerochaete chrysoporium Glyoxal Oxidase and its Application for the Coupled Reaction with Manganese Peroxidase to Decolorize Malachite Green

Science.gov (United States)

Son, Yu-Lim; Kim, Hyoun-Young; Thiyagarajan, Saravanakumar; Xu, Jing Jing

2012-01-01

cDNA of the glx1 gene encoding glyoxal oxidase (GLX) from Phanerochaete chrysosporium was isolated and expressed in Pichia pastoris. The recombinant GLX (rGLX) produces H2O2 over 7.0 nmol/min/mL using methyl glyoxal as a substrate. Use of rGLX as a generator of H2O2 improved the coupled reaction with recombinant manganese peroxidase resulting in decolorization of malachite green up to 150 µM within 90 min. PMID:23323052

Enhanced Sensitive Immunoassay: Noncompetitive Phage Anti-Immune Complex Assay for the Determination of Malachite Green and Leucomalachite Green

Science.gov (United States)

2015-01-01

To develop a more sensitive immunoassay for malachite green (MG) and leucomalachite green (LMG), we identified the immunocomplex binding phage-borne peptides for use in the noncompetitive phage anti-immunocomplex assay (PHAIA). An anti-LMG monoclonal antibody (mAb) was used to select immunocomplex binding peptides from a circular random eight-amino-acid phage-displayed library. After three rounds of panning-elution, five peptides that bound the LMG–mAb immunocomplex were obtained. One of the phage-borne peptide clones that resulted in an assay with the highest sensitivity was chosen for further research. The concentration of LMG producing 50% of the saturated signal and the limit of detection of the assay were 7.02 and 0.55 ng/mL, respectively, with a linear range of 1.35 to 21.56 ng/mL. The PHAIA based on the same antibody was 16 times more sensitive compared to the competitive immunoassay. PHAIA was used to analyze LMG, MG, and two mixtures of spiked fish samples, with validation by high-performance liquid chromatography (HPLC) with fluorescence detector. Results showed a good correlation (R2LMG = 0.9841; R2MG = 0.993; R2Mixture = 0.9903) between the data of PHAIA and HPLC, thus the assay was an efficient method for monitoring food safety. PMID:25077381

Fe3O4@mesoporous SBA-15: A magnetically recoverable catalyst for photodegradation of malachite green

International Nuclear Information System (INIS)

Aliyan, Hamid; Fazaeli, Razieh; Jalilian, Rahil

2013-01-01

Surface of mesostructured silica (SBA-15) was modified by immobilizing Fe 3 O 4 . This modified-nanosized mesoporous silica Fe 3 O 4 @SBA-15 was characterized by FTIR, XRD, BET and SEM. A comparison of the photoefficiency of Fe 3 O 4 @SBA-15 toward photodegradation of malachite green (MG) was investigated in a photocatalytic reactor using UV lamp as a light source. The effect of various experimental parameters on the degradation performance of the process was evaluated by examining catalyst dosage, initial dye concentration and pH of the dye solution in the presence of Fe 3 O 4 @SBA-15 as photocatalyst. It was found that the photocatalyst exhibited significantly high catalytic stability, and the activity loss is negligible after five MG degradation cycles.

Inorganic fullerene-type WS_2 nanoparticles: processing, characterization and its photocatalytic performance on malachite green

International Nuclear Information System (INIS)

Hazarika, Saurabh Jyoti; Mohanta, Dambarudhar

2017-01-01

In this work, we have employed a hydrothermal route for the synthesis of fullerene-type tungsten disulfide (WS_2) nanoparticles. X-ray diffraction analysis signifies a hexagonal crystal structure of WS_2 with the crystallites experiencing preferred orientations along (002) and (103) planes. The agglomerated nanoparticles and inorganic fullerene (IF)-type structures are apparently observable from the high-resolution electron micrographs. Raman spectrum shows prominent E"1_2_g and A_1_g modes emanating from the IF nano-WS_2 system. The Tauc's plot obtained from the optical absorption data predicts a direct band gap of ∝1.91 eV for the nano-WS_2 system; whereas, photoluminescence analysis reveals a broad emission peak located at ∝638 nm and is ascribed to the associated transition from the indirect to direct nature of the band gap. The photocatalytic decomposition of malachite green (MG) solution (30 mg/l) by WS_2 (100 mg/l) under UV and visible light irradiation has been evaluated. The latter condition exhibited a better photocatalytic response with the MG degradation as high as 71.2%, revealed for 120 min. Photocatalytic and optoelectronic features of IF-type nano-WS_2 would bring new insights not only to resolve issues related to environmental hazards, but also in functional devices of technological relevance. (orig.)

Optimization of Malachite Green Removal from Water by TiO₂ Nanoparticles under UV Irradiation.

Science.gov (United States)

Ma, Yongmei; Ni, Maofei; Li, Siyue

2018-06-13

TiO₂ nanoparticles with surface porosity were prepared by a simple and efficient method and presented for the removal of malachite green (MG), a representative organic pollutant, from aqueous solution. Photocatalytic degradation experiments were systematically conducted to investigate the influence of TiO₂ dosage, pH value, and initial concentrations of MG. The kinetics of the reaction were monitored via UV spectroscopy and the kinetic process can be well predicted by the pseudo first-order model. The rate constants of the reaction kinetics were found to decrease as the initial MG concentration increased; increased via elevated pH value at a certain amount of TiO₂ dosage. The maximum efficiency of photocatalytic degradation was obtained when the TiO₂ dosage, pH value and initial concentrations of MG were 0.6 g/L, 8 and 10 −5 mol/L (M), respectively. Results from this study provide a novel optimization and an efficient strategy for water pollutant treatment.

Malachite green decolorization by the filamentous fungus Myrothecium roridum--Mechanistic study and process optimization.

Science.gov (United States)

Jasińska, Anna; Paraszkiewicz, Katarzyna; Sip, Anna; Długoński, Jerzy

2015-10-01

The filamentous fungus Myrothecium roridum isolated from a dye-contaminated area was investigated in terms of its use for the treatment of Malachite green (MG). The mechanisms involved in this process were established. Peroxidases and cytochrome P-450 do not mediate MG elimination. The laccase of M. roridum IM 6482 was found to be responsible for the decolorization of 8-11% of MG. Thermostable low-molecular-weight factors (LMWF) resistant to sodium azide were found to be largely involved in dye decomposition. In addition, MG decolorization by M. roridum IM 6482 occurred in a non-toxic manner. Data from antimicrobial tests showed that MG toxicity decreased after decolorization. To optimize the MG decolorization process, the effects of operational parameters (such as the medium pH and composition, process temperature and culture agitation) were examined. The results demonstrate that M. roridum IM 6482 may be used effectively as an alternative to traditional decolorization agents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spent coffee grounds-based activated carbon preparation for sequestering of malachite green

Science.gov (United States)

Lim, Jun-Wei; Lam, Keat-Ying; Bashir, Mohammed J. K.; Yeong, Yin-Fong; Lam, Man-Kee; Ho, Yeek-Chia

2016-11-01

The key of reported work was to optimize the fabricating factors of spent coffee grounds-based activated carbon (SCG-bAC) used to sequester Malachite Green (MG) form aqueous solution via adsorption process. The fabricating factors of impregnation ratio with ortho-phosphoric acid, activation temperature and activation time were simultaneously optimized by central composite design (CCD) of response surface methodology (RSM) targeting on maximum removal of MG. At the optimum condition, 96.3% of MG was successfully removed by SCG-bAC at the impregnation ratio with ortho-phosphoric acid of 0.50, activation temperature of 554°C and activation time of 31.4 min. Statistical model that could predict the MG removal percentage was also derived and had been statistically confirmed to be significant. Subsequently, the MG adsorption equilibrium data was found well-fitted to Langmuir isotherm model, indicating the predominance of monolayer adsorption of MG on SCG-bAC surface. To conclude, the findings from the this study unveil the potential of spent coffee grounds as an alternative precursor in fabricating low-cost AC for the treatment of wastewater loaded with MG pollutant.

UV light induced photodegradation of malachite green on TiO2 nanoparticles

International Nuclear Information System (INIS)

Chen, C.C.; Lu, C.S.; Chung, Y.C.; Jan, J.L.

2007-01-01

The photodegradation of malachite green (MG), a cationic triphenylmethane dye, is examined both under different pH values and amounts of TiO 2 . After 15 W UV-365 nm irradiation for 4 h, ca. 99.9% of MG was degraded with addition of 0.5 g L -1 TiO 2 to solutions containing 50 mg L -1 of the MG dye. The HPLC-PDA-ESI-MS technique was used to obtain a better understanding on the mechanistic details of this TiO 2 -assisted photodegradation of the MG dye with UV irradiation. Five intermediates of the process were separated, identified, and characterized for the first time. The results indicated that the N-de-methylation degradation of MG dye took place in a stepwise manner to yield mono-, di-, tri-, and tetra-N-de-methylated MG species generated during the processes. Under acidic conditions, the results indicated that the photodegradation mechanism is favorable to cleavage of the whole conjugated chromophore structure of the MG dye. Under basic conditions, the results showed that the photodegradation mechanism is favorable to a formation of a series of N-de-methylated intermediates of the MG dye

Adsorption of malachite green and iodine on rice husk-based porous carbon

International Nuclear Information System (INIS)

Guo Yupeng; Zhang Hui; Tao Nannan; Liu Yanhua; Qi Juirui; Wang Zichen; Xu Hongding

2003-01-01

Adsorption isotherms of I 2 and malachite green (MG) by rice husk-based porous carbons (RHCs) from aqueous medium have been studied. Three samples of carbons prepared by NaOH-activation, three samples prepared by KOH-activation and two samples of commercial carbons have been studied. And the adsorption isotherms have been determined after modifying the carbon surfaces by oxidation with nitric acid and hydrogen peroxide and after degassing at 800 deg. C. The results have been found to follow the Freundlich adsorption isotherm. Three samples of N series have larger capacity for removing I 2 and MG from solution compared to that of the tested commercial carbons. The adsorption capacity of I 2 is similar for K series and commercial carbons. And the capacity of commercial carbons for MG is larger than K series. The adsorption capacity of I 2 on oxidation carbons has increased for hydrogen peroxide treatment and decreased for nitric acid, and that of MG is decreased. But the adsorption capacities of I 2 and MG increase on degassing. On the other hand, the adsorption of I 2 increases after modifying the carbon surfaces by HCl without oxidation. Suitable mechanisms have been proposed

Cathodic and anodic simultaneous electrolytic deposition to minimize copper and lead interferences on spectrophotometric determination of cadmium by the Malachite Green-iodide reaction

International Nuclear Information System (INIS)

Oliveira, Adriana Paiva de; Freschi, Gian Paulo Giovanni; Dakuzaku, Carolina Sinabucro; Moraes, Mercedes de; Crespi, Marisa Spirandeli; Gomes Neto, Jose de Anchieta

2001-01-01

Simultaneous electrolytic deposition is proposed for minimization of Cu 2+ and Pb 2+ interferences on automated determination of Cd 2+ by the Malachite Green-iodide reaction. During electrolysis of sample in a cell with two Pt electrodes and a medium adjusted to 5% (v/v) HNO 3 + 0.1% (v/v) H 2 SO 4 + 0.5 mol L -1 NaCl, Cu 2+ is deposited as Cu on the cathode, Pb 2+ is deposited as PbO 2 on the anode while Cd 2+ is kept in solution. With 60 s electrolysis time and 0.25 A current, Pb 2+ and Cu 2+ levels up to 50 and 250 mg L -1 respectively, can be tolerated without interference. With on-line extraction of Cd 2+ in anionic resin mini column, calibration graph in the 5.00 - 50.0 μg Cd L -1 range is obtained, corresponding to twenty measurements per hour, 0.7 mg Malachite Green and 500 mg Kl and 5 mL sample consumed per determination. Results of the determination of Cd in certified reference materials, vegetables and tap water were in agreement with certified values and with those obtained by GFAAS at 95% confidence level. The detection limit is 0.23 μg Cd L-1 and the RSD for typical samples containing 13.0 μg Cd L -1 was 3.85 % (n= 12). (author)

Isotherm and kinetics study of malachite green adsorption onto copper nanowires loaded on activated carbon: artificial neural network modeling and genetic algorithm optimization.

Science.gov (United States)

Ghaedi, M; Shojaeipour, E; Ghaedi, A M; Sahraei, Reza

2015-05-05

In this study, copper nanowires loaded on activated carbon (Cu-NWs-AC) was used as novel efficient adsorbent for the removal of malachite green (MG) from aqueous solution. This new material was synthesized through simple protocol and its surface properties such as surface area, pore volume and functional groups were characterized with different techniques such XRD, BET and FESEM analysis. The relation between removal percentages with variables such as solution pH, adsorbent dosage (0.005, 0.01, 0.015, 0.02 and 0.1g), contact time (1-40min) and initial MG concentration (5, 10, 20, 70 and 100mg/L) was investigated and optimized. A three-layer artificial neural network (ANN) model was utilized to predict the malachite green dye removal (%) by Cu-NWs-AC following conduction of 248 experiments. When the training of the ANN was performed, the parameters of ANN model were as follows: linear transfer function (purelin) at output layer, Levenberg-Marquardt algorithm (LMA), and a tangent sigmoid transfer function (tansig) at the hidden layer with 11 neurons. The minimum mean squared error (MSE) of 0.0017 and coefficient of determination (R(2)) of 0.9658 were found for prediction and modeling of dye removal using testing data set. A good agreement between experimental data and predicted data using the ANN model was obtained. Fitting the experimental data on previously optimized condition confirm the suitability of Langmuir isotherm models for their explanation with maximum adsorption capacity of 434.8mg/g at 25°C. Kinetic studies at various adsorbent mass and initial MG concentration show that the MG maximum removal percentage was achieved within 20min. The adsorption of MG follows the pseudo-second-order with a combination of intraparticle diffusion model. Copyright © 2015 Elsevier B.V. All rights reserved.

Photodegradation of malachite green dye catalyzed by Keggin-type polyoxometalates under visible-light irradiation: Transition metal substituted effects

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Liu, Chun-Guang; Zheng, Ting; Liu, Shuang; Zhang, Han-Yu

2016-04-01

In the present paper, Keggin-type polyoxometalates (POMs) (NH4)3[PW12O40] and its mono-transition-metal-substituted species (NH4)5[{PW11O39}MII(H2O)] (M = Mn, Fe, Co, Ni, Cu, Zn) have been synthesized and used as photocatalyst to activate O2 for the degradation of dye molecule under visible-light irradiation. Because of the strong adsorption on the surface of POM catalyst, malachite green (MG) molecule was employed as a molecular probe to test their photocatalytic activity. The photodegradation study shows that introduction of transition metal ion leads to an increase in the degradation of MG in the following order: Mn < Fe < Co < [PW12O40]3- < Ni < Cu < Zn, which indicates that the photocatalytic activity of these POMs is sensitive to the transition metal substituted effects. Electronic structure analysis based on the density functional theory calculations shows that a moderate decrease of oxidizing ability of POM catalyst may improve the photocatalytic activity in the degradation of dye molecule under visible-light irradiation. Meanwhile, intermediate products about the photocatalytic oxidation of MG molecule were proposed on the basis of gas chromatograph mass spectrometer analysis.

Application of Casuarina equisetifolia needle for the removal of methylene blue and malachite green dyes from aqueous solution

Directory of Open Access Journals (Sweden)

Muhammad Khairud Dahri

2015-12-01

Full Text Available This study investigated the potential of Casuarina equisetifolia needle (CEN on the removal of two important dyes, methylene blue (MB and malachite green (MG, by batch adsorption experiments. Characterisation of CEN’s functional groups was done using Fourier Transform infrared spectroscopy while elemental analysis was carried out using CHNS analysis and X-ray fluorescence. The experiments were carried out by varying the adsorbent dosage, pH, ionic strength, contact time and initial dye concentration. The pseudo-second-order kinetics model best represented the experimental data for both CEN-MB and CEN-MG systems. The Weber–Morris intraparticle diffusion model showed that intraparticle diffusion is not the rate-limited step for both adsorbates, while the Boyd model suggested both systems could be controlled by film diffusion. The Langmuir, Freundlich and Dubinin–Radushkevich isotherm models were used for describing the adsorption process. Of these, the Langmuir model best represented both adsorbents systems (CEN-MB and CEN-MG giving maximum adsorption capacity (qm of 110.8 and 77.6 mg g−1, respectively, at 25 °C. Thermodynamics studies showed that both adsorption systems are spontaneous and endothermic.

Use of Standing Gold Nanorods for Detection of Malachite Green and Crystal Violet in Fish by SERS.

Science.gov (United States)

Chen, Xiaowei; Nguyen, Trang H D; Gu, Liqun; Lin, Mengshi

2017-07-01

With growing consumption of aquaculture products, there is increasing demand on rapid and sensitive techniques that can detect prohibited substances in the seafood products. This study aimed to develop a novel surface-enhanced Raman spectroscopy (SERS) method coupled with simplified extraction protocol and novel gold nanorod (AuNR) substrates to detect banned aquaculture substances (malachite green [MG] and crystal violet [CV]) and their mixture (1:1) in aqueous solution and fish samples. Multivariate statistical tools such as principal component analysis (PCA) and partial least squares regression (PLSR) were used in data analysis. PCA results demonstrate that SERS can distinguish MG, CV and their mixture (1:1) in aqueous solution and in fish samples. The detection limit of SERS coupled with standing AuNR substrates is 1 ppb for both MG and CV in fish samples. A good linear relationship between the actual concentration and predicted concentration of analytes based on PLSR models with R 2 values from 0.87 to 0.99 were obtained, indicating satisfactory quantification results of this method. These results demonstrate that the SERS method coupled with AuNR substrates can be used for rapid and accurate detection of MG and CV in fish samples. © 2017 Institute of Food Technologists®.

Inorganic fullerene-type WS{sub 2} nanoparticles: processing, characterization and its photocatalytic performance on malachite green

Energy Technology Data Exchange (ETDEWEB)

Hazarika, Saurabh Jyoti; Mohanta, Dambarudhar [Tezpur University, Nanoscience and Soft Matter Laboratory, Department of Physics, Tezpur, Assam (India)

2017-05-15

In this work, we have employed a hydrothermal route for the synthesis of fullerene-type tungsten disulfide (WS{sub 2}) nanoparticles. X-ray diffraction analysis signifies a hexagonal crystal structure of WS{sub 2} with the crystallites experiencing preferred orientations along (002) and (103) planes. The agglomerated nanoparticles and inorganic fullerene (IF)-type structures are apparently observable from the high-resolution electron micrographs. Raman spectrum shows prominent E{sup 1}{sub 2g} and A{sub 1g} modes emanating from the IF nano-WS{sub 2} system. The Tauc's plot obtained from the optical absorption data predicts a direct band gap of ∝1.91 eV for the nano-WS{sub 2} system; whereas, photoluminescence analysis reveals a broad emission peak located at ∝638 nm and is ascribed to the associated transition from the indirect to direct nature of the band gap. The photocatalytic decomposition of malachite green (MG) solution (30 mg/l) by WS{sub 2} (100 mg/l) under UV and visible light irradiation has been evaluated. The latter condition exhibited a better photocatalytic response with the MG degradation as high as 71.2%, revealed for 120 min. Photocatalytic and optoelectronic features of IF-type nano-WS{sub 2} would bring new insights not only to resolve issues related to environmental hazards, but also in functional devices of technological relevance. (orig.)

Optimization of Malachite Green Removal from Water by TiO2 Nanoparticles under UV Irradiation

Directory of Open Access Journals (Sweden)

Yongmei Ma

2018-06-01

Full Text Available TiO2 nanoparticles with surface porosity were prepared by a simple and efficient method and presented for the removal of malachite green (MG, a representative organic pollutant, from aqueous solution. Photocatalytic degradation experiments were systematically conducted to investigate the influence of TiO2 dosage, pH value, and initial concentrations of MG. The kinetics of the reaction were monitored via UV spectroscopy and the kinetic process can be well predicted by the pseudo first-order model. The rate constants of the reaction kinetics were found to decrease as the initial MG concentration increased; increased via elevated pH value at a certain amount of TiO2 dosage. The maximum efficiency of photocatalytic degradation was obtained when the TiO2 dosage, pH value and initial concentrations of MG were 0.6 g/L, 8 and 10−5 mol/L (M, respectively. Results from this study provide a novel optimization and an efficient strategy for water pollutant treatment.

Using Ag/Ag2O/SnO2 Nanocomposites to Remove Malachite Green by a Photocatalytic Process

Science.gov (United States)

Taufik, A.; Paramarta, V.; Prakoso, S. P.; Saleh, R.

2017-03-01

Silver/silver oxide/tin oxide nanocomposites of various weight ratios were synthesized using a microwave-assisted method. The Ag/Ag2O:SnO2 nanoparticle weight ratios used were 25:75, 50:50, and 75:25. All samples were characterized using X-ray diffraction, UV-Vis spectroscopy, Differential Scanning Calorimetry and Thermogravimetric Analysis (TGA). The Ag/Ag2O/SnO2 nanocomposites contained cubic structures provided by the Ag and Ag2O and tetragonal structures provided by the SnO2. The silver resulted in surface plasmon resonance (SPR) at a wavelength of about 435 nm. The silver oxide material was transformed into pure Ag at a temperature of about 370 °C The photocatalytic activity was tested on the degradation of malachite green (MG) from an aqueous solution. The results showed that Ag/Ag2O/SnO2 at a ratio of 50:50 exhibited the best photocatalytic performance for degrading MG under visible-light irradiation. The degradation of MG using Ag/Ag2O/SnO2 nanocomposites followed pseudo first-order kinetic reactions, and electron holes were found to be the main species acting on the degradation process.

Adsorption of malachite green from aqueous solution by using novel chitosan ionic liquid beads.

Science.gov (United States)

Naseeruteen, Faizah; Hamid, Nur Shahirah Abdul; Suah, Faiz Bukhari Mohd; Ngah, Wan Saime Wan; Mehamod, Faizatul Shimal

2018-02-01

Chitosan ionic liquid beads were prepared from chitosan and 1-butyl-3-methylimidazolium based ionic liquids to remove Malachite Green (MG) from aqueous solutions. Batch adsorption experiments were carried out as a function of initial pH, adsorbent dosage, agitation time and initial MG concentration. The optimum conditions were obtained at pH 4.0, 0.008g of adsorbent dosage and 20min of agitation time were utilized in the kinetic and isotherm studies. Three kinetic models were applied to analyze the kinetic data and pseudo-second order was found to be the best fitted model with R 2 >0.999. In order to determine the adsorption capacity, the sorption data were analyzed using the linear form of Langmuir, Freundlich and Temkin equations. The isotherm was best fitted by Langmuir isotherm model. The maximum adsorption capacity (q max ) obtained from Langmuir isotherm for two chitosan beads 1-butyl-3-methylimidazolium acetate A and 1-butyl-3-methylimidazolium B are 8.07mgg -1 and 0.24mgg -1 respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

Photocatalytic degradation of Reactive Black 5 and Malachite Green with ZnO and lanthanum doped nanoparticles

International Nuclear Information System (INIS)

Kaneva, N; Bojinova, A; Papazova, K

2016-01-01

Here we report the preparation of ZnO particles with different concentrations of La 3 + doping (0, 0.5 and 1 wt%) via sol-gel method. The nanoparticles are synthesized directly from Zn(CH 3 COO) 2 .2H 2 O in the presence of 1-propanol and triethylamine at 80°C. The conditions are optimized to obtain particles of uniform size, easy to isolate and purify. The nanoparticles are characterized by SEM, XRD and UV-Vis analysis. The photocatalytic properties of pure and La-doped ZnO are studied in the photobleaching of Malachite Green (MG) and Reactive Black 5 (RB5) dyes in aqueous solutions upon UV illumination. It is observed that the rate constant increases with the La loading up to 1 wt%. The doping helps to achieve complete mineralization of MG within a short irradiation time. 1 wt% La-doped ZnO nanoparticles show highest photocatalytic activity. The La 3+ doped ZnO particles degrade faster RB5 than MG. The reason is weaker N=N bond in comparison with the C-C bond between the central carbon atom and N,N-dimethylaminobenzyl in MG. The as-prepared ZnO particles can find practical application in photocatalytic purification of textile wastewaters. (paper)

Determination of malachite green in fish based on magnetic molecularly imprinted polymer extraction followed by electrochemiluminescence.

Science.gov (United States)

Huang, Baomei; Zhou, Xibin; Chen, Jing; Wu, Guofan; Lu, Xiaoquan

2015-09-01

A novel procedure for selective extraction of malachite green (MG) from fish samples was set up by using magnetic molecularly imprinted polymers (MMIP) as the solid phase extraction material followed by electrochemiluminescence (ECL) determination. MMIP was prepared by using Fe3O4 magnetite as magnetic component, MG as template molecule, methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking agent. MMIP was characterized by SEM, TEM, FT-IR, VSM and XRD. Leucomalachite green (LMG) was oxidized in situ to MG by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). And then MMIP was successfully used to selectively enrich MG from fish samples. Adsorbed MG was desorbed and determined by ECL. Under the optimal conditions, calibration curve was good linear in the range of 0.29-290 μg/kg and the limit of detection (LOD) was 7.3 ng/kg (S/N=3). The recoveries of MMIP extraction were 77.1-101.2%. In addition, MMIP could be regenerated. To the best of our knowledge, MMIP coupling with ECL quenching of Ru(bpy)3(2+)/TPA for the determination of MG has not yet been developed. Copyright © 2015 Elsevier B.V. All rights reserved.

Accurate SERS detection of malachite green in aquatic products on basis of graphene wrapped flexible sensor.

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Ouyang, Lei; Yao, Ling; Zhou, Taohong; Zhu, Lihua

2018-10-16

Malachite Green (MG) is a banned pesticide for aquaculture products. As a required inspection item, its fast and accurate determination before the products' accessing market is very important. Surface enhanced Raman scattering (SERS) is a promising tool for MG sensing, but it requires the overcoming of several problems such as fairly poor sensitivity and reproducibility, especially laser induced chemical conversion and photo-bleaching during SERS observation. By using a graphene wrapped Ag array based flexible membrane sensor, a modified SERS strategy was proposed for the sensitive and accurate detection of MG. The graphene layer functioned as an inert protector for impeding chemical transferring of the bioproduct Leucomalachite Green (LMG) to MG during the SERS detection, and as a heat transmitter for preventing laser induced photo-bleaching, which enables the separate detection of MG and LMG in fish extracts. The combination of the Ag array and the graphene cover also produced plentiful densely and uniformly distributed hot spots, leading to analytical enhancement factor up to 3.9 × 10 8 and excellent reproducibility (relative standard deviation low to 5.8% for 70 runs). The proposed method was easily used for MG detection with limit of detection (LOD) as low as 2.7 × 10 -11  mol L -1 . The flexibility of the sensor enable it have a merit for in-field fast detection of MG residues on the scale of a living fish through a surface extraction and paste transferring manner. The developed strategy was successfully applied in the analysis of real samples, showing good prospects for both the fast inspection and quantitative detection of MG. Copyright © 2018 Elsevier B.V. All rights reserved.

Sorption of malachite green from aqueous solution by potato peel: Kinetics and equilibrium modeling using non-linear analysis method

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El-Khamsa Guechi

2016-09-01

Full Text Available Potato peel (PP was used as a biosorbent to remove malachite green (MG from aqueous solution under various operating conditions. The effect of the experimental parameters such as initial dye concentration, biosorbent dose, initial pH, stirring speed, temperature, ionic strength and biosorbent particle size was investigated through a number of batch sorption experiments. The sorption kinetic uptake for MG by PP at various initial dye concentrations was analyzed by non-linear method using pseudo-first, pseudo-second and pseudo-nth order models. It was found that the pseudo-nth order kinetic model was the best applicable model to describe the sorption kinetic data and the order n of sorption reaction was calculated in the range from 0.71 to 2.71. Three sorption isotherms namely the Langmuir, Freundlich and Redlich–Peterson isotherms in their non-linear forms were applied to the biosorption equilibrium data. Both the Langmuir and Redlich–Peterson models were found to fit the sorption isotherm data well, but the Redlich–Peterson model was better. Thermodynamic parameters show that the sorption process of MG is endothermic and more effective process at high temperatures. The results revealed that PP is very effective for the biosorption of MG from aqueous solutions.

Effect of malachite green toxicity on non target soil organisms.

Science.gov (United States)

Gopinathan, R; Kanhere, J; Banerjee, J

2015-02-01

Although malachite green (MG), is banned in Europe and US for its carcinogenic and teratogenic effect, the dye being cheap, is persistently used in various countries for fish farming, silk, dye, leather and textile industries. Current research, however, fails to elucidate adequate knowledge concerning the effects of MG in our ecosystem. In the present investigation, for the first time, an attempt has been made to study the effects of MG on soil biota by testing Bacillus subtilis, Azotobacter chroococcum, Saccharomyces cerevisiae, Penicillium roqueforti, Eisenia fetida and seeds of three crop plants of different families. Various tests were conducted for determining cytotoxicity, genotoxicity, acute toxicity, morphological and germination effect. Our data confirmed MG toxicity on fungi and bacteria (gram positive and gram negative organisms) showing elevated level of ROS. Genotoxicity caused in the microorganisms was detected by DNA polymorphism and fragmentation. Also, scanning electron microscopy data suggests that the inhibitory effect of MG to these beneficial microbes in the ecosystem might be due to pore formation in the cell and its eventual disruption. Filter paper and artificial soil test conducted on earthworms demonstrated a LC 50 of 2.6 mg cm(-2) and 1.45 mg kg(-1) respectively with severe morphological damage. However, seed germination of Mung bean, Wheat and Mustard was found to be unaffected in presence of MG up to 100 mL(-1) concentration. Thus, understanding MG toxicity in non target soil organisms and emphasis on its toxicological effects would potentially explicate its role as an environmental contaminant. Copyright © 2014 Elsevier Ltd. All rights reserved.

A rapid molecular diagnosis of cutaneous leishmaniasis bycolorimetric malachite green-loop-mediated isothermal amplification(LAMP) combined with an FTA card as a direct sampling tool

OpenAIRE

Nzelu, Chukwunonso O.; Cáceres, Abraham G.; Guerrero-Quincho, Silvia; Tineo-Villafuerte, Edwin; Rodriquez-Delfin, Luis; Mimori, Tatsuyuki; Uezato, Hiroshi; Katakura, Ken; Gomez, Eduardo A.; Guevara, Angel G.; Hashiguchi, Yoshihisa; Kato, Hirotomo

2015-01-01

Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64 degrees C for 60 mm using a heatin...

Graphene oxide membrane as an efficient extraction and ionization substrate for spray-mass spectrometric analysis of malachite green and its metabolite in fish samples.

Science.gov (United States)

Wei, Shih-Chun; Fan, Shen; Lien, Chia-Wen; Unnikrishnan, Binesh; Wang, Yi-Sheng; Chu, Han-Wei; Huang, Chih-Ching; Hsu, Pang-Hung; Chang, Huan-Tsung

2018-03-20

A graphene oxide (GO) nanosheet-modified N + -nylon membrane (GOM) has been prepared and used as an extraction and spray-ionization substrate for robust mass spectrometric detection of malachite green (MG), a highly toxic disinfectant in liquid samples and fish meat. The GOM is prepared by self-deposition of GO thin film onto an N + -nylon membrane, which has been used for efficient extraction of MG in aquaculture water samples or homogenized fish meat samples. Having a dissociation constant of 2.17 × 10 -9  M -1 , the GOM allows extraction of approximately 98% of 100 nM MG. Coupling of the GOM-spray with an ion-trap mass spectrometer allows quantitation of MG in aquaculture freshwater and seawater samples down to nanomolar levels. Furthermore, the system possesses high selectivity and sensitivity for the quantitation of MG and its metabolite (leucomalachite green) in fish meat samples. With easy extraction and efficient spray ionization properties of GOM, this membrane spray-mass spectrometry technique is relatively simple and fast in comparison to the traditional LC-MS/MS methods for the quantitation of MG and its metabolite in aquaculture products. Copyright © 2017 Elsevier B.V. All rights reserved.

Voltammetric determination of heparin based on its interaction with malachite green

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Xueliang Niu

2008-08-01

Full Text Available In this paper malachite green (MG was used as a bioprobe to determine heparin concentration by linear sweep voltammetry on the dropping mercury working electrode (DME. In Britton-Robinson (B-R buffer solution of pH 1.5, MG had a well-defined second order derivative linear sweep voltammetric reductive peak at –0.618 V (vs. SCE. After the addition of heparin into the MG solution, the reductive peak current decreased apparently without the movement of peak potential. Based on the difference of the peak current, a new voltammetric method for the determination of heparin was established. The conditions for the binding reaction and the electrochemical detection were optimized. Under the selected experimental conditions the difference of peak current was directly proportional to the concentration of heparin in the range from 0.3 to 10.0 mg/L with the linear regression equation as ∆ip″ (nA = 360.19 C (mg/L + 178.88 (n = 15, γ = 0.998 and the detection limit as 0.28 mg/L (3σ. The effects of coexisting substances such as metal ions, amino acids on the determination of heparin were investigated and the results showed that this method had good selectivity. This method was further applied to determine the heparin content in heparin sodium injection samples with satisfactory results and good recovery. The stoichiometry of the biocomplex was calculated by the electrochemical method and the binding mechanism was further discussed.

Studies on the Removal of Rhodamine B and Malachite Green from Aqueous Solutions by Activated Carbon

Directory of Open Access Journals (Sweden)

A. Edwin Vasu

2008-01-01

Full Text Available Activated carbon prepared from tamarind fruit shells by direct carbonization was used for the removal of rhodamine B and malachite green dyes from aqueous solutions. Adsorption studies were performed by varying such parameters as dye concentration, pH of the dye solution, time and temperature. The equilibrium adsorption data obtained were used to calculate the Freundlich, Langmuir and Redlich-Peterson isotherm parameters. Increase in pH of the solution pH resulted in increased adsorption of both the dyes. Kinetic studies indicate that the pseudo-second order model can be used for describing the dynamics of the sorption processes. Film diffusion of the dyes was the rate determining step at low dye concentrations while diffusion of dyes through the pores the carbon particles determined the overall uptake at high concentrations. Thermodynamic parameters of the endothermic sorptions were evaluated using van’t Hoff equation. Desorption studies with acids were also performed in order to regenerate the used carbons.

Remarkable photo-catalytic degradation of malachite green by nickel doped bismuth selenide under visible light irradiation

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Kulsi, Chiranjit; Ghosh, Amrita; Mondal, Anup; Kargupta, Kajari; Ganguly, Saibal; Banerjee, Dipali

2017-01-01

Bismuth selenide (Bi2Se3) and nickel (Ni) doped Bi2Se3 were prepared by a solvothermal approach to explore the photo-catalytic performance of the materials in degradation of malachite green (MG). The presence of nickel was confirmed by X-ray photoelectron spectroscopy (XPS) measurement in doped Bi2Se3. The results showed that the nickel doping played an important role in microstructure and photo-catalytic activity of the samples. Nickel doped Bi2Se3 sample exhibited higher photo-catalytic activity than that of the pure Bi2Se3 sample under visible-light irradiation. The photo-catalytic degradation followed first-order reaction kinetics. Fast degradation kinetics and complete (100% in 5 min of visible light irradiation) removal of MG was achieved by nickel doped Bi2Se3 in presence of hydrogen peroxide (H2O2) due to modification of band gap energies leading to suppression of photo-generated electron-hole recombination.

Sonocatalytic degradation of malachite green oxalate by a semiconductor metal oxide nanocatalyst.

Science.gov (United States)

Bhavani, R; Sivasamy, A

2016-12-01

Advanced Oxidation Process (AOP) technologies are considered to be better technique for the degradation or mineralization of many recalcitrant compounds and pollutants. In the present study heterogeneous sonocatalytic degradation of a model organic compound such as Malachite green oxalate (MGO) was carried out in the aqueous phase. Zinc oxide nanorods were prepared by precipitation method employing zinc acetates as precursors and were characterized by FT-IR, XRD, FE-SEM and EDAX analysis. Degradation of MGO in the aqueous phase was studied in detail under the sonocatalytic process. Effects of pH, dye concentration, oxidant concentration, kinetics and effect of electrolytes on dye degradation were carried out to check the efficiency of the sonocatalyst. Effect of energy input on the degradation processes was also investigated. The degradation of dye molecules were monitored by UV-visible spectrophotometer and Chemical Oxygen demand (COD). The dye molecules were readily degraded at above 90% in the pH range 5.0-7.0 under ultrasound with zinc oxide nanorods. The interference of electrolytes like NaCl, KCl, Na 2 CO 3 , NaHCO 3 and MgSO 4 on the degradation of dye molecules were also studied on the sonocatalytic degradation of MGO. From the kinetic studies it was observed that at lower initial concentration of dye molecules the degradation efficiency was above 90%. The rate of the reaction decreased on increasing the initial dye concentrations of the dye molecules. It was observed that the complete mineralization of dye molecules was achieved without the formation of toxic by-products. The reusability of the catalyst also showed the effective degradation of the dye molecules up to five cycles without loss of the catalytic activities. Copyright © 2015 Elsevier Inc. All rights reserved.

Structural characterization of mesoporous magnetite nanoparticles synthesized using the leaf extract of Calliandra haematocephala and their photocatalytic degradation of malachite green dye

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Sirdeshpande, Karthikey Devadatta; Sridhar, Anushka; Cholkar, Kedar Mohan; Selvaraj, Raja

2018-03-01

A simple method for the synthesis of magnetite nanoparticles using the leaf extract of Calliandra haematocephala has been developed. UV-Vis spectrum showed a characteristic strong absorption band. SEM image revealed the bead-like spherical nanoparticles. EDS showed the prominent peaks for elemental iron and oxygen. PXRD patterns confirmed the crystalline nature and the average crystallite size of 7.45 nm. In addition, the lattice parameter value was calculated to be 8.413 Å, close to Fe3O4 nanoparticles. BET analysis disclosed the total specific surface area of the nanoparticles as 63.89 m2/g and the mesoporous structure of the nanoparticles with a pore radius of 34.18 Å. FTIR studies showed the specific bands at 599.82 and 472.53 cm-1, typical for Fe3O4 nanoparticles. The photocatalytic efficacy of the nanoparticles was demonstrated against the degradation of malachite green dye under sunlight irradiation and the photocatalytic degradation constant was calculated as 0.0621 min-1.

Biomimetic ELISA detection of malachite green based on magnetic molecularly imprinted polymers.

Science.gov (United States)

Li, Lu; Lin, Zheng-Zhong; Peng, Ai-Hong; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

2016-11-01

A direct competitive enzyme-linked immunosorbent assay (ELISA) method was used for the detection of malachite green (MG) with a high sensitivity and selectivity using magnetic molecularly imprinted polymers (MMIPs) as a bionic antibody. MMIPs were prepared through emulsion polymerization using Fe 3 O 4 nanoparticles as magnetic nuclei, MG as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent and span-80/tween-80 as mixed emulsifiers. The MMIPs were characterized by scanning electron micrographs (SEM), thermal-gravimetric analyzer (TGA), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. A high magnetic saturation value of 54.1emug -1 was obtained, resulting in rapid magnetic separation of MMIPs with an external magnet. The IC 50 of the established ELISA method was 20.1μgL -1 and the detection limit (based on IC 85 ) was 0.1μgL -1 . The MMIPs exhibited high selective binding capacity for MG with cross-reactivities less than 3.9% for MG structural analogues. The MG spiking recoveries were 85.0%-106% with the relative standard deviations less than 4.7%. The results showed that the biomimetic ELISA method by using MMIPs as bionic antibody could be used to detect MG rapidly in fish samples with a high sensitivity and accuracy. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficient removal of malachite green dye using biodegradable graft copolymer derived from amylopectin and poly(acrylic acid).

Science.gov (United States)

Sarkar, Amit Kumar; Pal, Aniruddha; Ghorai, Soumitra; Mandre, N R; Pal, Sagar

2014-10-13

This article reports on the application of a high performance biodegradable adsorbent based on amylopectin and poly(acrylic acid) (AP-g-PAA) for removal of toxic malachite green dye (MG) from aqueous solution. The graft copolymer has been synthesized and characterized using various techniques including FTIR, GPC, SEM and XRD analyses. Biodegradation study suggests that the co-polymer is biodegradable in nature. The adsorbent shows excellent potential (Qmax, 352.11 mg g(-1); 99.05% of MG has been removed within 30 min) for removal of MG from aqueous solution. It has been observed that point to zero charge (pzc) of graft copolymer plays significant role in adsorption efficacy. The adsorption kinetics and isotherm follow pseudo-second order and Langmuir isotherm models, respectively. Thermodynamics parameters suggest that the process of dye uptake is spontaneous. Finally desorption study shows excellent regeneration efficiency of adsorbent. Copyright © 2014 Elsevier Ltd. All rights reserved.

Irradiation-induced fusion between giant vesicles and photoresponsive large unilamellar vesicles containing malachite green derivative.

Science.gov (United States)

Uda, Ryoko M; Yoshikawa, Yuki; Kitaba, Moe; Nishimoto, Noriko

2018-07-01

Light-initiated fusion between vesicles has attracted much attention in the research community. In particular, fusion between photoresponsive and non-photoresponsive vesicles has been of much interest in the development of systems for the delivery of therapeutic agents to cells. We have performed fusion between giant vesicles (GVs) and photoresponsive smaller vesicles containing malachite green (MG) derivative, which undergoes ionization to afford a positive charge on the molecule by irradiation. The fusion proceeds as the concentration of GV lipid increases toward equimolarity with the lipid of the smaller vesicle. It is also dependent on the molar percentage of photoionized MG in the lipid of the smaller vesicle. On the other hand, the fusion is hardly affected by the anionic component of the GV. The photoinduced fusion was characterized by two methods, involving the mixing of lipid membranes and of aqueous contents. Fluorescence microscopy revealed that irradiation triggered the fusion of a single GV with the smaller vesicles containing MG. Copyright © 2018 Elsevier B.V. All rights reserved.

Analysis of malachite green in aquatic products by carbon nanotube-based molecularly imprinted - matrix solid phase dispersion.

Science.gov (United States)

Wang, Yu; Chen, Ligang

2015-10-01

A simple method based on matrix solid phase dispersion (MSPD) using molecularly imprinted polymers (MIPs) as sorbents for selective extraction of malachite green (MG) from aquatic products was developed. The MIPs were prepared by using carbon nanotube as support, MG as template, methacrylic acid as functional monomer, ethyleneglycol dimethacrylate as crosslinker and methylene chloride as solvent. The MIPs were characterized by Fourier transform infrared spectrometry and transmission electron microscopy. The isothermal adsorption, kinetics absorption and selective adsorption experiments were carried out. We optimized the extraction conditions as follows: the ratio of MIPs to sample was 2:3, the dispersion time was 15min, washing solvent was 4mL 50% aqueous methanol and elution solvent was 3mL methanol-acetic acid (98: 2, v/v). Once the MSPD process was completed, the MG extracted from aquatic products was determined by high performance liquid chromatography. The detection limit of MG was 0.7μgkg(-1). The relative standard deviations of intra-day and inter-day were obtained in the range of 0.9%-4.7% and 3.4%-9.8%, respectively. In order to evaluate the applicability and reliability of the proposed method, it was applied to determine MG in different aquatic products samples including fish, shrimp, squid and crabs. The satisfied recoveries were in the range of 89.2%-104.6%. The results showed that this method is faster, simpler and makes extraction and purification in the same system. Copyright © 2015 Elsevier B.V. All rights reserved.

Multiscale Modeling of Plasmon-Exciton Dynamics of Malachite Green Monolayers on Gold Nanoparticles

Science.gov (United States)

Smith, Holden; Karam, Tony; Haber, Louis; Lopata, Kenneth

A multi-scale hybrid quantum/classical approach using classical electrodynamics and a collection of discrete two-level quantum system is used to investigate the coupling dynamics of malachite green monolayers adsorbed to the surface of a spherical gold nanoparticle (NP). This method utilizes finite difference time domain (FDTD) to describe the plasmonic response of the NP and a two-level quantum description for the molecule via the Maxwell/Liouville equation. The molecular parameters are parameterized using CASPT2 for the energies and transition dipole moments, with the dephasing lifetime fit to experiment. This approach is suited to simulating thousands of molecules on the surface of a plasmonic NP. There is good agreement with experimental extinction measurements, predicting the plasmon and molecule depletions. Additionally, this model captures the polariton peaks overlapped with a Fano-type resonance profile observed in the experimental extinction measurements. This technique shows promise for modeling plasmon/molecule interactions in chemical sensing and light harvesting in multi-chromophore systems. This material is based upon work supported by the National Science Foundation under the NSF EPSCoR Cooperative Agreement No. EPS-1003897 and by the Louisiana Board of Regents Research Competitiveness Subprogram under Contract Number LEQSF(2014-17)-RD-A-0.

Surfactant-free synthesis of octahedral ZnO/ZnFe2O4 heterostructure with ultrahigh and selective adsorption capacity of malachite green

Science.gov (United States)

Liu, Jue; Zeng, Min; Yu, Ronghai

2016-05-01

A new octahedral ZnO/ZnFe2O4 heterostructure has been fabricated through a facile surfactant-free solvothermal method followed by thermal treatment. It exhibits a record-high adsorption capacity (up to 4983.0 mg·g-1) of malachite green (MG), which is a potentially harmful dye in prevalence and should be removed from wastewater and other aqueous solutions before discharging into the environment. The octahedral ZnO/ZnFe2O4 heterostructure also demonstrates strong selective adsorption towards MG from two kinds of mixed solutions: MG/methyl orange (MO) and MG/rhodamine B (RhB) mixtures, indicating its promise in water treatment.

Reusable nanosilver-coated magnetic particles for ultrasensitive SERS-based detection of malachite green in water samples

Science.gov (United States)

Song, Dan; Yang, Rong; Wang, Chongwen; Xiao, Rui; Long, Feng

2016-01-01

A novel nanosilver-deposited silica-coated Fe3O4 magnetic particle (Fe3O4@SiO2@Ag) with uniform size, good SERS activity and magnetic responsiveness was synthesized using amination polymer. The Fe3O4@SiO2@Ag magnetic particles have been successfully applied for ultrasensitive SERS detection of malachite green (MG) in water samples. The mechanism is that MG can be adsorbed on the silver surface of nanosilver-coated magnetic particles via one nitrogen atom, and the Raman signal intensity of MG is significantly enhanced by the nanosilver layer formed on the magnetic particles. The developed sensing system exhibited a sensitive response to MG in the range of 10 fM to 100 μM with a low limit of detection (LOD) 2 fM under optimal conditions. The LOD was several orders of magnitude lower than those of other methods. This SERS-based sensor showed good reproducibility and stability for MG detection. The silver-coated magnetic particles could easily be regenerated as SERS substrates only using low pH solution for multiple sensing events. The recovery of MG added to several water samples at different concentrations ranged from 90% to 110%. The proposed method facilitates the ultrasensitive analysis of dyes to satisfy the high demand for ensuring the safety of water sources. PMID:26964502

Fe(III)-loaded collagen fiber as a heterogeneous catalyst for the photo-assisted decomposition of Malachite Green

International Nuclear Information System (INIS)

Liu Xiaohu; Tang Rui; He Qiang; Liao Xuepin; Shi Bi

2010-01-01

A heterogeneous catalyst for Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber and its catalytic activity for the photo-assisted decomposition of Malachite Green (MG) was investigated. The results indicated that this Fe(III)-immobilized collagen fiber (Fe-CF) can effectively catalyse the decoloration and decomposition/mineralization of MG in aqueous solution. Catalysed by Fe-CF, MG solution was completely decolorized in 30 min, while 55.0% of TOC was removed from the dye solution within 120 min in the presence of H 2 O 2 and UVA irradiation (365 nm, 10 W). Fe-CF was recycled for seven times with certain activity loss (32.6% in decoloration, 18.5% in TOC removal), and its catalytic activity can be easily recovered by re-immobilization of Fe(III). Therefore, Fe-CF could act as an efficient and cost-effective catalyst for the photo-assisted decomposition of MG, and shows potential applications in practice.

Molecularly imprinted polymers for extraction of malachite green from fish samples prior to its determination by HPLC

International Nuclear Information System (INIS)

Li, Lu; Chen, Xiao-mei; Zhang, Hong-yuan; Lin, Yi-dong; Lin, Zheng-zhong; Huang, Zhi-yong; Lai, Zhu-zhi

2015-01-01

Molecularly imprinted polymer (MIP) particles for malachite green (MG) were prepared by emulsion polymerization using methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, and a combination of Span-80 and Tween-80 as an emulsifier. The MIP particles were characterized by SEM micrographs and FT-IR spectra. Their binding capacity for MG was evaluated based on kinetic and isothermal adsorption experiments and compared to non-imprinted polymer particles. Analytical figures of merit include an adsorption equilibrium time of 15 min, an adsorption capacity of 1.9 mg∙g -1 in acetonitrile-water (20:80), and an imprinting factor of 1.85. The MIP particles were successfully applied to the extraction of MG from fish samples spiked with MG and the other interfering substances prior to its determination of MG by HPLC. Spiked samples gave recoveries of MG that ranged from 86 to 104 %, much higher than that of the other interfering substance. (author)

Antimicrobial photodynamic inactivation of Staphylococcus aureus biofilms in bone specimens using methylene blue, toluidine blue ortho and malachite green: An in vitro study.

Science.gov (United States)

Rosa, Luciano Pereira; da Silva, Francine Cristina; Nader, Sumaia Alves; Meira, Giselle Andrade; Viana, Magda Souza

2015-05-01

To evaluate the in vitro effectiveness of APDI with a 660 nm laser combined with methylene blue (MB), toluidine blue ortho (TBO) and malachite green (MG) dyes to inactivate Staphylococcus aureus (ATCC 25923) biofilms in compact and cancellous bone specimens. Eighty specimens of compact and 80 of cancellous bone were contaminated with a standard suspension of the microorganism and incubated for 14 days at 37°C to form biofilms. After this period, the specimens were divided into groups (n=10) according to established treatment: PS-L- (control - no treatment); PSmb+L-, PStbo+L-, PSmg+L- (only MB, TBO or MG for 5 min in the dark); PS-L+ (only laser irradiation for 180 s); and APDImb, APDItbo and APDImg (APDI with MB, TBO or MG for 180 s). The findings were statistically analyzed by ANOVA at 5% significance levels. All experimental treatments showed significant reduction of log CFU/mL S. aureus biofilms when compared with the control group for compact and cancellous bones specimens; the APDI group's treatment was more effective. The APDI carried out for the compact specimens showed better results when compared with cancellous specimens at all times of application. For the group of compact bone, APDImg showed greater reductions in CFU/mL (4.46 log 10). In the group of cancellous bone, the greatest reductions were found in the APDImb group (3.06 log 10). APDI with methylene blue, toluidine blue ortho and malachite green dyes and a 660 nm laser proved to be effective in the inactivation of S. aureus biofilms formed in compact and cancellous bone. Copyright © 2015 Elsevier Ltd. All rights reserved.

Investigation kinetics mechanisms of adsorption malachite green onto activated carbon

International Nuclear Information System (INIS)

Onal, Y.; Akmil-Basar, C.; Sarici-Ozdemir, C.

2007-01-01

Lignite was used to prepare activated carbon (T3K618) by chemical activation with KOH. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by t-plot based on N 2 adsorption isotherm. BET surface area of activated carbon is determined as 1000 m 2 /g. Adsorption capacity of malachite green (MG) onto T3K618 activated carbon was investigated in a batch system by considering the effects of various parameters like initial concentration (100, 150 and 200 mg/L) and temperature (25, 40 and 50 deg. C). The adsorption process was relatively fast and equilibrium was reached after about 20 min for 100, 150 mg/L at all adsorption temperature. Equilibrium time for 200 mg/L was determined as 20 min and 40 min at 298, 313 and 323 K, respectively. Simple mass and kinetic models were applied to the experimental data to examine the mechanisms of adsorption and potential rate controlling steps such as external mass transfer, intraparticle diffusion. Pseudo second-order model was found to explain the kinetics of MG adsorption most effectively. It was found that both mass transfer and pore diffusion are important in determining the adsorption rates. The intraparticle diffusion rate constant, external mass transfer coefficient, film and pore diffusion coefficient at various temperatures were evaluated. The activation energy (E a ) was determined as 48.56, 63.16, 67.93 kJ/mol for 100, 150, 200 mg/L, respectively. The Langmiur and Freundlich isotherm were used to describe the adsorption equilibrium studies at different temperatures. Langmiur isotherm shows better fit than Freundlich isotherm in the temperature range studied. The thermodynamic parameters, such as ΔG o , ΔS and ΔH o were calculated. The thermodynamics of dyes-T3K618 system indicates endothermic process

Adsorption and desorption of cationic malachite green dye on cellulose nanofibril aerogels.

Science.gov (United States)

Jiang, Feng; Dinh, Darren M; Hsieh, You-Lo

2017-10-01

Ultra-light aerogels have been assembled from cellulose nanofibrils into hierarchically macroporous (several hundred μm) honeycomb cellular structure surrounded with mesoporous (8-60nm) thin walls. The high specific surface (193m 2 /g) and surface carboxyl content (1.29mmol/g) of these aerogels were demonstrated to be highly capable of removing cationic malachite green (MG) dye from aqueous media. The rapid MG adsorption was driven by electrostatic interactions and followed a pseudo-second-order adsorption kinetic and monolayer Langmuir adsorption isotherm. At a low 1:5mg/mL aerogel/MG ratio, both initial MG adsorption rate (2.3-59.8mgg -1 min -1 ) and equilibrium adsorption capacity (53.0-203.7mgg -1 ) increased with increasing initial MG concentrations from 10 to 200mg/L, reaching a maximum adsorption of 212.7mgg -1 . The excellent dye removal efficiency was demonstrated by complete MG removal through four repetitive adsorptions at a low 1:5mg/mL aerogel/MG ratio and 10mg/L dye concentration as well as 92% MG adsorption in a single batch at one order of magnitude higher10:5mg/mL aerogel/MG ratio and 100mg/L dye concentration. The adsorbed MG in aerogels could be desorbed in aqueous media by increasing ionic strength, demonstrating facile recovery of both dye and aerogel as well as the robust capability of this aerogel for repetitive applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Adsorption of Methylene Blue Malachite Green from aqueous solution on the surface of Wool Carbonizing Waste

International Nuclear Information System (INIS)

Khan, A. R.; Tahir, H.; Fahimuddin; Waqar, S. S.

2005-01-01

With ever increasing environmental pollution problems, the present day study was related to the removal of colorants. Synthetic colorants represented a relatively large group of organic chemicals. Such chemicals have undesirable effects not only on the environment but also on human beings. Present study is related with the removal of basic dyes methylene blue and malachite green using wool carbonizing waste materials as adsorbent. Adsorption of dyes is carried out as a function of temperature, amount of adsorbent, pH and duration. Spectrophotomeric technique was adopted for measuring the extent of adsorption. The data are fitted in Langmuir and Freundlich isotherm equations and their corresponding constants are calculated. Thermodynamic study is also carried out by calculating the values of thermodynamic parameters such as, enthalpy change (delta H), free energy change (delta G) and entropy change (delta S). The values of percent removal and KD for each dye system is also calculated at the range of temperatures ranging from 293-323K with the intervals of 10C+-0.2C. (author)

Facile synthesis of three-dimensional diatomite/manganese silicate nanosheet composites for enhanced Fenton-like catalytic degradation of malachite green dye

Science.gov (United States)

Jiang, De Bin; Yuan, Yunsong; Zhao, Deqiang; Tao, Kaiming; Xu, Xuan; Zhang, Yu Xin

2018-05-01

In this work, we demonstrate a novel and simple approach for fabrication of the complex three-dimensional (3D) diatomite/manganese silicate nanosheet composite (DMSNs). The manganese silicate nanosheets are uniformly grown on the inner and outer surface of diatomite with controllable morphology using a hydrothermal method. Such structural features enlarged the specific surface area, resulting in more catalytic active sites. In the heterogeneous Fenton-like reaction, the DMSNs exhibited excellent catalytic capability for the degradation of malachite green (MG). Under optimum condition, 500 mg/L MG solution was nearly 93% decolorized at 70 min in the reaction. The presented results show an enhanced catalytic behavior of the DMSNs prepared by the low-cost natural diatomite material and simple controllable process, which indicates their potential for environmental remediation applications. [Figure not available: see fulltext.

Rapid detection of multidrug-resistant Mycobacterium tuberculosis using the malachite green decolourisation assay

Science.gov (United States)

Coban, Ahmet Yilmaz; Uzun, Meltem

2013-01-01

Early detection of drug resistance in Mycobacterium tuberculosis isolates allows for earlier and more effective treatment of patients. The aim of this study was to investigate the performance of the malachite green decolourisation assay (MGDA) in detecting isoniazid (INH) and rifampicin (RIF) resistance in M. tuberculosis clinical isolates. Fifty M. tuberculosis isolates, including 19 multidrug-resistant, eight INH-resistant and 23 INH and RIF-susceptible samples, were tested. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and agreement of the assay for INH were 92.5%, 91.3%, 92.5%, 91.3% and 92%, respectively. Similarly, the sensitivity, specificity, PPV, NPV and agreement of the assay for RIF were 94.7%, 100%, 100%, 96.8% and 98%, respectively. There was a major discrepancy in the tests of two isolates, as they were sensitive to INH by the MGDA test, but resistant by the reference method. There was a minor discrepancy in the tests of two additional isolates, as they were sensitive to INH by the reference method, but resistant by the MGDA test. The drug susceptibility test results were obtained within eight-nine days. In conclusion, the MGDA test is a reliable and accurate method for the rapid detection of INH and RIF resistance compared with the reference method and the MGDA test additionally requires less time to obtain results. PMID:24402143

Biosorption of malachite green from aqueous solutions by Pleurotus ostreatus using Taguchi method

Science.gov (United States)

2014-01-01

Dyes released into the environment have been posing a serious threat to natural ecosystems and aquatic life due to presence of heat, light, chemical and other exposures stable. In this study, the Pleurotus ostreatus (a macro-fungus) was used as a new biosorbent to study the biosorption of hazardous malachite green (MG) from aqueous solutions. The effective disposal of P. ostreatus is a meaningful work for environmental protection and maximum utilization of agricultural residues. The operational parameters such as biosorbent dose, pH, and ionic strength were investigated in a series of batch studies at 25°C. Freundlich isotherm model was described well for the biosorption equilibrium data. The biosorption process followed the pseudo-second-order kinetic model. Taguchi method was used to simplify the experimental number for determining the significance of factors and the optimum levels of experimental factors for MG biosorption. Biosorbent dose and initial MG concentration had significant influences on the percent removal and biosorption capacity. The highest percent removal reached 89.58% and the largest biosorption capacity reached 32.33 mg/g. The Fourier transform infrared spectroscopy (FTIR) showed that the functional groups such as, carboxyl, hydroxyl, amino and phosphonate groups on the biosorbent surface could be the potential adsorption sites for MG biosorption. P. ostreatus can be considered as an alternative biosorbent for the removal of dyes from aqueous solutions. PMID:24620852

Rapid detection of multidrug-resistant Mycobacterium tuberculosis using the malachite green decolourisation assay

Directory of Open Access Journals (Sweden)

Ahmet Yilmaz Coban

2013-12-01

Full Text Available Early detection of drug resistance in Mycobacterium tuberculosis isolates allows for earlier and more effective treatment of patients. The aim of this study was to investigate the performance of the malachite green decolourisation assay (MGDA in detecting isoniazid (INH and rifampicin (RIF resistance in M. tuberculosis clinical isolates. Fifty M. tuberculosis isolates, including 19 multidrug-resistant, eight INH-resistant and 23 INH and RIF-susceptible samples, were tested. The sensitivity, specificity, positive predictive value (PPV, negative predictive value (NPV and agreement of the assay for INH were 92.5%, 91.3%, 92.5%, 91.3% and 92%, respectively. Similarly, the sensitivity, specificity, PPV, NPV and agreement of the assay for RIF were 94.7%, 100%, 100%, 96.8% and 98%, respectively. There was a major discrepancy in the tests of two isolates, as they were sensitive to INH by the MGDA test, but resistant by the reference method. There was a minor discrepancy in the tests of two additional isolates, as they were sensitive to INH by the reference method, but resistant by the MGDA test. The drug susceptibility test results were obtained within eight-nine days. In conclusion, the MGDA test is a reliable and accurate method for the rapid detection of INH and RIF resistance compared with the reference method and the MGDA test additionally requires less time to obtain results.

Enhanced sulfidation xanthate flotation of malachite using ammonium ions as activator

OpenAIRE

Dandan Wu; Wenhui Ma; Yingbo Mao; Jiushuai Deng; Shuming Wen

2017-01-01

In this study, ammonium ion was used to enhance the sulfidation flotation of malachite. The effect of ammonium ion on the sulfidation flotation of malachite was investigated using microflotation test, inductively coupled plasma (ICP) analysis, zeta potential measurements, and scanning electron microscope analysis (SEM). The results of microflotation test show that the addition of sodium sulfide and ammonium sulfate resulted in better sulfidation than the addition of sodium sulfide alone. The ...

Adsorption of malachite green from aqueous solution onto carbon prepared from Arundo donax root

International Nuclear Information System (INIS)

Zhang Jian; Li Yan; Zhang Chenglu; Jing Yuming

2008-01-01

Arundo donax root carbon (ADRC), a new adsorbent, was prepared from Arundo donax root by carbonization. The surface area of the adsorbent was determined 158 m 2 /g by N 2 adsorption isotherm. Batch adsorption experiments were carried out for the removal of malachite green (MG) from aqueous solution using ADRC as adsorbent. The effects of various parameters such as solution pH (3-10), carbon dose (0.15-1.0 g/100 ml) and initial MG concentration (10-100 mg/l) on the adsorption system were investigated. The effective pH was 5-7 and the optimum adsorbent dose was found to be 0.6 g/100 ml. Equilibrium experimental data at 293, 303 and 313 K were better represented by Langmuir isotherm than Freundlich isotherm using linear and non-linear methods. Thermodynamic parameters such as ΔG, ΔH and ΔS were also calculated. The negative Gibbs free energy change and the positive enthalpy change indicated the spontaneous and endothermic nature of the adsorption. The adsorption equilibrium time was 180 min. Adsorption kinetics was determined using pseudo-first-order model, pseudo-second-order model and intraparticle diffusion model. The results showed that the adsorption of MG onto ADRC followed pseudo-second-order model

Preparation of novel oxidized mesoporous carbon with excellent adsorption performance for removal of malachite green and lead ion

Science.gov (United States)

Zhang, Xialan; Lin, Qilang; Luo, Shiyuan; Ruan, Kezhao; Peng, Kaiping

2018-06-01

An oxidized mesoporous carbon (OMC) with fluffy structure was fabricated from the mixture of petroleum asphalt and aluminum isopropoxide, and its structures were characterized by FESEM, TEM, BET, TG, XPS and FT-IR. In addition, bath absorption experiments for malachite green (MG) and lead ion (Pb2+) were carried out to explore the effects of pH, initial concentration, contact time and temperature on its absorption process. Results show that the OMC prepared has a fluffy ultrathin-wall structure with narrow pore size distribution and rich oxygen-containing groups. It exhibits excellent absorption performance for the removal of MG as well as Pb2+, as indicated by that its maximum adsorption capacity is 963.1 mg g-1 for MG and 198.6 mg g-1 for Pb2+. The absorption experimental data are all fitted well with pseudo-second-order model and Frendlich isotherm, respectively. More importantly, the OMC still maintains relatively high adsorption capacity after five cycles.

Use of kaolin as a potential low-cost adsorbent for the removal of malachite green from colored effluents

Energy Technology Data Exchange (ETDEWEB)

Foletto, E.L.; Caponi, N.; Collazzo, G.C.; Jahn, S.L.; Dotto, G.L.; Mazutti, M.A. [Universidade Federal de Santa Maria (UFSM), RS (Brazil)

2016-07-01

Full text: This study investigated the potential of raw kaolin as a low-cost adsorbent for the removal Malachite Green (MG) from colored effluents. The morphology, chemical structure and the surface properties of the adsorbent were investigated by characterization techniques such as X-ray diffraction, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, X-ray fluorescence spectroscopy and scanning electron microscopy. A possible technological application of kaolin is the MG removal from aqueous media, which was investigated by batch adsorption experiments. The adsorption kinetics was studied using the pseudo-first order, pseudo-second order and Elovich models. The adsorption isotherms were studied using Langmuir, Freundlich and Sips models. Maximum adsorption capacity was found to be 128 mg g-1, and this satisfactory result may be associated to some properties of adsorbent. Therefore, the results of this investigation revealed that kaolin can be utilized as a promising low-cost adsorbent to remove MG from colored effluents. (author)

Fast removal of malachite green dye using novel superparamagnetic sodium alginate-coated Fe3O4 nanoparticles.

Science.gov (United States)

Mohammadi, Abbas; Daemi, Hamed; Barikani, Mehdi

2014-08-01

In this study, superparamagnetic sodium alginate-coated Fe3O4 nanoparticles (Alg-Fe3O4) as a novel magnetic adsorbent were prepared by in situ coprecipitation method, in which Fe3O4 nanoparticles were precipitated from FeCl3 and FeCl2 under alkaline medium in the presence of sodium alginate. The Alg-Fe3O4 nanoparticles were used for removal of malachite green (MG) from aqueous solutions using batch adsorption technique. The characterization of synthesized nanoparticles was performed using XRD, FTIR, TEM, TGA and vibrating sample magnetometer (VSM) techniques. FTIR analysis of synthesized nanoparticles provided the evidence that sodium alginate was successfully coated on the surface of Fe3O4 nanoparticles. The FT-IR and TGA characterization showed that the Alg-Fe3O4 nanoparticles contained about 14% (w/w) of sodium alginate. Moreover, TEM analysis indicated that the average diameter of the Alg-Fe3O4 nanoparticles was about 12nm. The effects of adsorbent dosage, pH and temperature were investigated on the adsorption properties of MG onto Alg-Fe3O4 nanoparticles. The equilibrium adsorption data were modeled using the Langmuir and Freundlich isotherms. The maximum adsorption capacity obtained from Langmuir isotherm equation was 47.84mg/g. The kinetics of adsorption of MG onto Alg-Fe3O4 nanoparticles were investigated using the pseudo-first-order and pseudo-second-order kinetic models. The results showed that the adsorption of MG onto nanoparticles followed pseudo-second-order kinetic model. Copyright © 2014 Elsevier B.V. All rights reserved.

Curly malachite on archaeological bronze : A systematic study of the shape and phenomenological approach of its formation mechanism

NARCIS (Netherlands)

Nienhuis, J.; Robbiola, Luc; Giuliani, Roberta; Joosten, Ineke; Huisman, Hans; van Os, Bertil; Sietsma, J.

2016-01-01

Curly malachite (CM) is found as a green cupric carbonate hydroxide corrosion product on archaeological bronze, mostly on artefacts retrieved from graves. In this paper, a morphological characterization approach is proposed, enabling the investigation of the formation process of CM. It is suggested

Efficient removal of chromate and arsenate from individual and mixed system by malachite nanoparticles

International Nuclear Information System (INIS)

Saikia, Jiban; Saha, Bedabrata; Das, Gopal

2011-01-01

Graphical abstract: Malachite nanoparticles of 100-150 nm, have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate in pH range 4-5. - Abstract: Malachite nanoparticles of 100-150 nm have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate. We report a high adsorption capacity for chromate and arsenate on malachite nanoparticle from both individual and mixed solution in pH ∼4-5. However, the adsorption efficiency decreases with the increase of solution pH. Batch studies revealed that initial pH, temperature, malachite nanoparticles dose and initial concentration of chromate and arsenate were important parameters for the adsorption process. Thermodynamic analysis showed that adsorption of chromate and arsenate on malachite nanoparticles is endothermic and spontaneous. The adsorption of these anions has also been investigated quantitatively with the help of adsorption kinetics, isotherm, and selectivity coefficient (K) analysis. The adsorption data for both chromate and arsenate were fitted well in Langmuir isotherm and preferentially followed the second order kinetics. The binding affinity of chromate is found to be slightly higher than arsenate in a competitive adsorption process which leads to the comparatively higher adsorption of chromate on malachite nanoparticles surface.

A novel biochar from Manihot esculenta Crantz waste: application for the removal of Malachite Green from wastewater and optimization of the adsorption process.

Science.gov (United States)

Beakou, Buscotin Horax; El Hassani, Kaoutar; Houssaini, Mohammed Amine; Belbahloul, Mounir; Oukani, Elhassan; Anouar, Abdellah

2017-09-01

The adsorptive removal of Malachite Green (MG) by a novel biochar namely Cassava Rind Carbon (CRC) was studied in a batch system. Moreover, Box-Behnken Response Surface Methodology was used to optimize operating conditions of the adsorption process. Characterization was done by Thermo Gravimetric Analysis (TGA), Attenuated Total Reflectance Fourier Transform Infra-Red Spectroscopy (ATR/FTIR), Brunauer-Emmett-Teller (BET) surface area, Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and pH zero charge point (pH ZCP ). The pseudo-second-order model and Langmuir model provided the best fit for kinetic and isotherm, respectively. The maximum capacity of dye adsorbed was 932.98 mg/g at 25 °C. The influence of temperature, the mass of adsorbent and the concentration of dye was studied. The optimal amount of adsorbed MG was 1,363.58 mg/g corresponding to 50 °C, 5 mg of CRC and 150 mg/L of dye. According to the high performance exhibited by CRC in this study, Manihot esculenta Crantz waste can be used as a better and low-cost biomass for wastewater decolourization.

Highly efficient decolorization of Malachite Green by a novel Micrococcus sp. strain BD15.

Science.gov (United States)

Du, Lin-Na; Zhao, Ming; Li, Gang; Zhao, Xiao-Ping; Zhao, Yu-Hua

2011-08-01

Malachite Green (MG) is used for a variety of applications but is also known to be carcinogenic and mutagenic. In this study, a novel Micrococcus sp. (strain BD15) was observed to efficiently decolorize MG. The purposes of this study were to explore the optimal conditions for decolorization and to evaluate the potential use of this strain for MG decolorization. Optical microscope and UV-visible analyses were carried out to determine whether the decolorization was due to biosorption or biodegradation. A Plackett-Burman design was employed to investigate the effect of various parameters on decolorization, and response surface methodology was then used to explore the optimal decolorization conditions. Kinetics analysis and antimicrobial activity tests were also performed. The results indicated that the decolorization by the strain was mainly due to biodegradation. Concentrations of MG, urea, and yeast extract and inoculum size had significantly positive effects on MG decolorization, while concentrations of CuCl(2) and MgCl(2), and temperature had significantly negative effects. The interaction between different parameters could significantly affect decolorization, and the optimal conditions for decolorization were 1.0 g/L urea, 0.9 g/L yeast extract, 100 mg/L MG, 0.1 g/L inoculums (dry weight), and incubation at 25.2°C. Under the optimal conditions, 96.9% of MG was removed by the strain within 1 h, which represents highly efficient microbial decolorization. Moreover, the kinetic data for decolorization fit a second-order model well, and the strain showed a good MG detoxification capability. Based on the results of this study, we propose Micrococcus sp. strain BD15 as an excellent candidate strain for MG removal from wastewater.

Synthesis, Characterization, and Use of Novel Bimetal Oxide Catalyst for Photoassisted Degradation of Malachite Green Dye

Directory of Open Access Journals (Sweden)

K. L. Ameta

2014-01-01

Full Text Available This work reports a simple, novel, and cost effective synthesis of nanobimetal oxide catalyst using cerium and cadmium nitrates as metal precursors. The cerium-cadmium oxide nanophotocatalyst was synthesized by coprecipitation method and characterized by X-ray powder diffraction method to analyze the particle size. XRD study reveals a high degree of crystallinity and 28.43 nm particle size. The photocatalytic efficiency of the synthesized nanobimetal catalyst was examined by using it for the photocatalytic degradation of malachite green dye. Experiments were conducted to study the effect of various parameters, such as the pH of the dye solution, concentration of dye, amount of catalyst, and light intensity on the rate of dye degradation. The progress of the dye degradation was monitored spectrophotometrically by taking the optical density of the dye solution at regular intervals. Experimental results indicate that the dye degrades best at pH 8.0 with light intensity 600 Wm−2 and catalyst loading 0.03 g/50 mL of dye solution. The rate constant for the reaction was 7.67 × 10−4 s−1.

Efficient removal of chromate and arsenate from individual and mixed system by malachite nanoparticles.

Science.gov (United States)

Saikia, Jiban; Saha, Bedabrata; Das, Gopal

2011-02-15

Malachite nanoparticles of 100-150 nm have been efficiently and for the first time used as an adsorbent for the removal of toxic arsenate and chromate. We report a high adsorption capacity for chromate and arsenate on malachite nanoparticle from both individual and mixed solution in pH ∼4-5. However, the adsorption efficiency decreases with the increase of solution pH. Batch studies revealed that initial pH, temperature, malachite nanoparticles dose and initial concentration of chromate and arsenate were important parameters for the adsorption process. Thermodynamic analysis showed that adsorption of chromate and arsenate on malachite nanoparticles is endothermic and spontaneous. The adsorption of these anions has also been investigated quantitatively with the help of adsorption kinetics, isotherm, and selectivity coefficient (K) analysis. The adsorption data for both chromate and arsenate were fitted well in Langmuir isotherm and preferentially followed the second order kinetics. The binding affinity of chromate is found to be slightly higher than arsenate in a competitive adsorption process which leads to the comparatively higher adsorption of chromate on malachite nanoparticles surface. Copyright © 2010 Elsevier B.V. All rights reserved.

In vitro interactions of malachite green and leucomalachite green with hepatic drug-metabolizing enzyme systems in the rainbow trout (Onchorhyncus mykiss).

Science.gov (United States)

Nebbia, Carlo; Girolami, Flavia; Carletti, Monica; Gasco, Laura; Zoccarato, Ivo; Giuliano Albo, Alessandra

2017-10-05

Malachite green (MG) has been widely used in aquaculture to treat a number of microbial and parasitic diseases. It is currently banned in the EU because of the high cytotoxicity and carcinogenic activity, which is also shared by leucomalachite green (LMG), a reduced MG metabolite that can persist in fish tissues for months. There is scant information about the ability of either compound to interact with drug metabolizing enzymes in fish. Therefore we evaluated the in vitro effects of MG and LMG (25, 50 and 100μM) on some DMEs and glutathione (GSH) content in rainbow trout liver subfractions. LMG did not affect any of the examined parameters. In contrast, MG proved to deplete GSH and to depress to a various extent the activities of NAD(P)H cytochrome c reductase, 7-ethoxycoumarin O-deethylase, 1-naphthol uridindiphosphoglucuronyl-transferase and maximally those of 7-ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) accepting 1-chloro2,4-dinitrobenzene (CDNB) as substrate. The inhibition mechanisms of EROD and GST were investigated by means of non-linear Michaelis-Menten kinetics and Lineweaver-Burk plots using 0.175-8μM MG. The calculated IC 50 for EROD was 7.1μM, and the inhibition appeared to be competitive (K i 2.78±0.24μM). In the case of GST, the calculated IC 50 was 0.53μM. The inhibition was best described as competitive toward GSH (Ki 0.39±0.02μM) and of mixed-type toward CDNB (Ki 0.64±0.06μM). Our findings indicate that, contrary to LMG, MG behaves as a relatively strong inhibitor of certain liver DMEs and can reversibly bind GSH. Copyright © 2017 Elsevier B.V. All rights reserved.

Rapid detection of malachite green in fish based on CdTe quantum dots coated with molecularly imprinted silica.

Science.gov (United States)

Wu, Le; Lin, Zheng-Zhong; Zhong, Hui-Ping; Peng, Ai-Hong; Chen, Xiao-Mei; Huang, Zhi-Yong

2017-08-15

A sensitive fluorescence sensor for the detection of malachite green (MG) was fabricated by grafting molecularly imprinted polymers (MIPs) onto the surface of CdTe quantum dots (QDs). The MIP-coated QDs were synthesized via a reverse microemulsion method using (3-aminopropyl)triethoxysilane (APTES) and tetraethyl orthosilicate (TEOS) as functional monomer and cross-linker, respectively. The optimum molar ratio of MG, functional monomer and cross-linker was 1:3:10. The MIP-coated QDs exhibited uniform spheres with diameter around 49nm and excellent fluorescence emission at λ ex 370nm. A linear relationship with two segments between the relative fluorescence intensities and the MG concentrations ranging from 0.08 to 20μmol·L -1 could be obtained with a detection limit of 12μg·kg -1 . The fluorescent probe was successfully applied to the determination of MG in fish samples with the spiked recoveries ranging from 94.3% to 109.5% which were in accordance with those of the measurement by HPLC-UV. Copyright © 2017 Elsevier Ltd. All rights reserved.

RNA Seq analysis of the role of calcium chloride stress and electron transport in mitochondria for malachite green decolorization by Aspergillus niger.

Science.gov (United States)

Gomaa, Ola M; Selim, Nabila S; Wee, Josephine; Linz, John E

2017-08-01

Aspergillus niger was previously demonstrated to decolorize the commercial dye malachite green (MG) and this process was enhanced under calcium chloride (CaCl 2 ) treatment. Previous data also suggested that the decolorization process is related to mitochondrial cytochrome c. In the current work, we analyzed in depth the specific relationship between CaCl 2 treatment and MG decolorization. Gene expression analysis (RNA Seq) using Next Generation Sequencing (NGS) revealed up-regulation of 28 genes that are directly or indirectly associated with stress response functions as early as 30min of CaCl 2 treatment; these data further strengthen our previous findings that CaCl 2 treatment induces a stress response in A. niger which enhances the ability to decolorize MG. A significant increase in fluorescence observed by MitoTracker dye suggests that CaCl 2 treatment also increased mitochondrial membrane potential. Isolated mitochondrial membrane protein fractions obtained from A. niger grown under standard growth conditions decolorized MG in the presence of NADH and decolorization was enhanced in samples isolated from CaCl 2 -treated A. niger cultures. Treatment of whole mitochondrial fraction with KCN which inhibits electron transport by cytochrome c oxidase and Triton-X 100 which disrupts mitochondrial membrane integrity suggests that cyanide sensitive cytochrome c oxidase activity is a key biochemical step in MG decolorization. This suggestion was confirmed by the addition of palladium α-lipoic acid complex (PLAC) which resulted in an initial increase in decolorization. Although the role of cytochrome c and cytochrome c oxidase was confirmed at the biochemical level, changes in levels of transcripts encoding these enzymes after CaCl 2 treatment were not found to be statistically significant in RNA Seq analysis. These data suggest that the regulation of cytochrome c enzymes occur predominantly at the post-transcriptional level under CaCl 2 stress. Thus, using global

Malachite green mediates homodimerization of antibody VL domains to form a fluorescent ternary complex with singular symmetric interfaces

Science.gov (United States)

Szent-Gyorgyi, Chris; Stanfield, Robyn L.; Andreko, Susan; Dempsey, Alison; Ahmed, Mushtaq; Capek, Sara; Waggoner, Alan; Wilson, Ian A.; Bruchez, Marcel P.

2013-01-01

We report that a symmetric small molecule ligand mediates the assembly of antibody light chain variable domains (VLs) into a correspondent symmetric ternary complex with novel interfaces. The L5* Fluorogen Activating Protein (FAP) is a VL domain that binds malachite green dye (MG) to activate intense fluorescence. Crystallography of liganded L5* reveals a 2:1 protein:ligand complex with inclusive C2 symmetry, where MG is almost entirely encapsulated between an antiparallel arrangement of the two VL domains. Unliganded L5* VL domains crystallize as a similar antiparallel VL/VL homodimer. The complementarity determining regions (CDRs) are spatially oriented to form novel VL/VL and VL/ligand interfaces that tightly constrain a propeller conformer of MG. Binding equilibrium analysis suggests highly cooperative assembly to form a very stable VL/MG/VL complex, such that MG behaves as a strong chemical inducer of dimerization. Fusion of two VL domains into a single protein tightens MG binding over 1,000-fold to low picomolar affinity without altering the large binding enthalpy, suggesting that bonding interactions with ligand and restriction of domain movements make independent contributions to binding. Fluorescence activation of a symmetrical fluorogen provides a selection mechanism for the isolation and directed evolution of ternary complexes where unnatural symmetric binding interfaces are favored over canonical antibody interfaces. As exemplified by L5*, these self-reporting complexes may be useful as modulators of protein association or as high affinity protein tags and capture reagents. PMID:23978698

Photo-triggered release from liposomes without membrane solubilization, based on binding to poly(vinyl alcohol) carrying a malachite green moiety.

Science.gov (United States)

Uda, Ryoko M; Kato, Yutaka; Takei, Michiko

2016-10-01

When working with liposomes analogous to cell membranes, it is important to develop substrates that can regulate interactions with the liposome surface in response to light. We achieved a photo-triggered release from liposomes by using a copolymer of poly(vinyl alcohol) carrying a malachite green moiety (PVAMG). Although PVAMG is a neutral polymer under dark conditions, it is photoionized upon exposure to UV light, resulting in the formation of a cationic site for binding to liposomes with a negatively charged surface. Under UV irradiation, PVAMG showed effective interaction with liposomes, releasing the encapsulated compound; however, this release was negligible under dark conditions. The poly(vinyl alcohol) moiety of PVAMG played an important role in the photo-triggered release. This release was caused by membrane destabilization without lipid solubilization. We also investigated different aspects of liposome/PVAMG interactions, including PVAMG-induced fusion between the liposomes and the change in the liposome morphologies. Copyright © 2016 Elsevier B.V. All rights reserved.

Cr(OH)3-NPs-CNC hybrid nanocomposite: a sorbent for adsorptive removal of methylene blue and malachite green from solutions.

Science.gov (United States)

Nekouei, Farzin; Nekouei, Shahram; Keshtpour, Farzaneh; Noorizadeh, Hossein; Wang, Shaobin

2017-11-01

In this article, Cr(OH) 3 nanoparticle-modified cellulose nanocrystal (CNC) as a novel hybrid nanocomposite (Cr(OH) 3 -NPs-CNC) was prepared by a simple procedure and used as a sorbent for adsorptive removal of methylene blue (MB) and malachite green (MG) from aqueous solution. Different kinetic models were tested, and the pseudo-second-order kinetic model was found more suitable for the MB and MG adsorption processes. The BET and Langmuir models were more suitable for the adsorption processes of MB and MG. Thermodynamic studies suggested that the adsorption of MB and MG onto Cr(OH) 3 -NPs-CNC nanocomposite was a spontaneous and endothermic process. The maximum adsorption capacities for MB and MG were reached 106 and 104 mg/g, respectively, which were almost two times higher than unmodified CNC. The chemical stability and leaching tests of the Cr(OH) 3 -NPs-CNC hybrid nanocomposite showed that only small amounts of chromium were leached into the solution.

Application of Response Surface Methodology to Optimize Malachite Green Removal by Cl-nZVI Nanocomposites

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Farshid Ghorbani

2017-09-01

Full Text Available Disposal of effluents containing dyes into natural ecosystems pose serious threats to both the environment and its aquatic life. Malachite green (MG is a basic dye that has extensive industrial applications, especially in aquaculture, throughout the world. This study reports on the application of the central composite design (CCD under the response surface methodology (RSM for the optimization of MG adsorption from aqueous solutions using the clinoptilolite nano-zerovalence iron (Cl-nZVI nanocomposites. The sorbent structures produced are characterized by means of scanning electron micrograph (SEM, energy-dispersive X-ray spectroscopy (EDS, and vibrating sample magnetometer (VSM. The effects of different parameters including pH, initial MG concentration, and sorbent dosage on the removal efficiency (R of MG were studied to find the optimum operating conditions. For this purpose, a total of 20 sets of experiments were designed by the Design Expert.7.0 software and the values of removal efficiency were used as input response to the software. The optimum pH, initial MG concentration, and sorbent dosage were found to be 5.6, 49.21 mg.L-1, and 1.43 g.L-1, respectively. A high MG removal efficiency (57.90% was obtained with optimal process parameters. Moreover, a desirability value of 0.963 was obtained for the optimization process.

Optimization of the Adsorption of Malachite Green on the NH2-SBA-15 Nano-adsorbent Using the Taguchi Method by Qualitek-4 Software An Isotherm, Kinetic, and Thermodynamic Study

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Arghavan Mirahsani

2015-01-01

Full Text Available SBA-15 nanoporous silica was prepared and functionalized with propylamine groups via post-synthesis grafting to develop efficient adsorbents of dyes in wastewater. The materials thus prepared were then characterized by XRD, N2 adsorption-desorption, and FTIR. Adsorption of a cationic dye, malachite green, on functionalized SBA-15 was investigated under various conditions of pH (5, 6, and 7, temperature (10, 20, and 30 °C, adsorbent dosage (0.1, 0.3, and 0.5 g/L, and dye concentration (50, 100, 150, 200, 250, 300 mg/L. Maximum equilibrium adsorption capacity to achieve maximum removal percentage (R%=100% in optimum conditions (dye concentration=100 mg/L, pH=7, adsorbent dosage= 0.3 g/L was estimated at 333 mg/g. The Taguchi method was used to optimize the adsorption performances of the materials , and then the isotherm, kinetic, and thermodynamic properties were analyzed under the optimum conditions. The results showed that the overall process was fast and its kinetics was well-fitted by pseudo-second-order kinetic model. The experimental data agreed well with Freundlich model. Therefore, the maximum amount of multilayer dye adsorbed was estimated as 500 mg/g. Based on the results obtained, this process may be regarded as an endothermic one with a negative ∆G, which shows the process is also spontaneous. Finally, the results indicate that the silica‐based nanoporous organic–inorganic hybrid material can be a promising sorbent for the removal of malachite green from aquatic solutions

Adsorption of malachite green on groundnut shell waste based powdered activated carbon

International Nuclear Information System (INIS)

Malik, R.; Ramteke, D.S.; Wate, S.R.

2007-01-01

In the present technologically fast changing situation related to waste management practices, it is desirable that disposal of plant waste should be done in a scientific manner by keeping in view economic and pollution considerations. This is only possible when the plant waste has the potential to be used as raw material for some useful product. In the present study, groundnut shell, an agricultural waste, was used for the preparation of an adsorbent by chemical activation using ZnCl 2 under optimized conditions and its comparative characterisation was conducted with commercially available powdered activated carbon (CPAC) for its physical, chemical and adsorption properties. The groundnut shell based powdered activated carbon (GSPAC) has a higher surface area, iodine and methylene blue number compared to CPAC. Both of the carbons were used for the removal of malachite green dye from aqueous solution and the effect of various operating variables, viz. adsorbent dose (0.1-1 g l -1 ), contact time (5-120 min) and adsorbate concentrations (100-200 mg l -1 ) on the removal of dye, has been studied. The experimental results indicate that at a dose of 0.5 g l -1 and initial concentration of 100 mg l -1 , GSPAC showed 94.5% removal of the dye in 30 min equilibrium time, while CPAC removed 96% of the dye in 15 min. The experimental isotherm data were analyzed using the linearized forms of Freundlich, Langmuir and BET equations to determine maximum adsorptive capacities. The equilibrium data fit well to the Freundlich isotherm, although the BET isotherm also showed higher correlation for both of the carbons. The results of comparative adsorption capacity of both carbons indicate that groundnut shell can be used as a low-cost alternative to commercial powdered activated carbon in aqueous solution for dye removal

Efficient photocatalytic degradation of malachite green dye under visible irradiation by water soluble ZnS:Mn/ZnS core/shell nanoparticles

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Khaparde, Rohini A.; Acharya, Smita A.

2018-05-01

ZnS:Mn/ ZnS core/shell nanoparticles was prepared by two step synthesis method. In first step, oleic acid - coated Mn doped ZnS core nanoparticles were prepared which were charged through ligand exchange. Shell of ZnS NPs was finally deposited upon the surface of charged Mn doped ZnS core. Scanning electron microscopy (SEM) image exhibit morphological confirmation of ZnS:Mn/ZnS core/shell. As Nano ZnS are the most suitable candidates for photocatalyst that extensively involved in degradation and complete mineralization of various toxic organic pollutants owing to its high efficiency, strong oxidizing power, non-toxicity, high photochemical and biological stability, corrosive resistance and low cost. Photodegradation of malachite green is systematically investigated by adding different molar proportional of ZnS:Mn/ZnS core/shell in the dye. The rate of de-coloration of dye is detected by UV-VIS absorption spectroscopy. Efficient detoriation in the colour of dye is attributed to the core /shell morphology of the particles.

Modeling of Malachite Green Removal from Aqueous Solutions by Nanoscale Zerovalent Zinc Using Artificial Neural Network

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Wenqian Ruan

2017-12-01

Full Text Available The commercially available nanoscale zerovalent zinc (nZVZ was used as an adsorbent for the removal of malachite green (MG from aqueous solutions. This material was characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The advanced experimental design tools were adopted to study the effect of process parameters (viz. initial pH, temperature, contact time and initial concentration and to reduce number of trials and cost. Response surface methodology and rapidly developing artificial intelligence technologies, i.e., artificial neural network coupled with particle swarm optimization (ANN-PSO and artificial neural network coupled with genetic algorithm (ANN-GA were employed for predicting the optimum process variables and obtaining the maximum removal efficiency of MG. The results showed that the removal efficiency predicted by ANN-GA (94.12% was compatible with the experimental value (90.72%. Furthermore, the Langmuir isotherm was found to be the best model to describe the adsorption of MG onto nZVZ, while the maximum adsorption capacity was calculated to be 1000.00 mg/g. The kinetics for adsorption of MG onto nZVZ was found to follow the pseudo-second-order kinetic model. Thermodynamic parameters (ΔG0, ΔH0 and ΔS0 were calculated from the Van’t Hoff plot of lnKc vs. 1/T in order to discuss the removal mechanism of MG.

Application of potato (Solanum tuberosum plant wastes for the removal of methylene blue and malachite green dye from aqueous solution

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Neha Gupta

2016-09-01

Full Text Available Dye pollutants from the textile, paper, and leather industries are important sources of environmental contamination. In the present study an agricultural waste from potato plant (potato stem powder, PSP and potato leaves powder, PLP was used as an adsorbent for removal of the methylene blue (MB and malachite green (MG dyes from aqueous solution. The adsorbent materials were characterized by scanning electron microscope (SEM and Fourier transform infrared (FTIR spectroscopy. Batch experiments were performed to investigate the effect of physico-chemical parameters, such as pHpzc, ionic strength, adsorbent dose, contact time, initial dyes concentration and temperature. The kinetics of adsorption was studied by applying the pseudo-first order, pseudo-second order and intraparticle diffusion models. The pseudo-second order model better represented the adsorption kinetics and the mechanism was controlled by surface adsorption and intraparticle diffusion. Equilibrium data were analyzed using Langmuir and Freundlich isotherm models. The thermodynamic parameters such as change in enthalpy (ΔH°, entropy (ΔS° and Gibb’s free energy (ΔG° of adsorption systems were also determined and evaluated.

CNT supported Mn-doped ZnO nanoparticles: simple synthesis and improved photocatalytic activity for degradation of malachite green dye under visible light

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Mohamed, R. M.; Shawky, Ahmed

2018-03-01

Hexagonal ZnO nanoparticles doped with Mn and supported with a minor amount of carbon nanotubes (CNTs) were synthesized through a simple coprecipitation-ultrasonication process with high yield. The effect of Mn doping, as well as CNTs addition on structure, surface morphology and texture, optical and electronic properties, was studied. We found that just 1% Mn doping and 1% CNT addition on ZnO showed the best crystallinity, highest surface area, improved visible light absorption, and a lowest estimated band gap of 2.6 eV with minimum charge recombination as revealed from photoluminescence spectra. The application of the optimum composition of the synthesized sample for the photodegradation of malachite green dye showed enhanced photocatalytic activity > 95% under visible light irradiation within 120 min at a minimum dosage of 0.1 g L-1 without any using of hole scavenger or changing the pH. This work highlighting the humble preparation procedure and develops photocatalysis research for real industrial applications.

A chemometric-assisted method for the simultaneous determination of malachite green and crystal violet in water based on absorbance-pH data generated by a homemade pH gradient apparatus.

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Yu, Shuling; Yuan, Xuejie; Yang, Jing; Yuan, Jintao; Shi, Jiahua; Wang, Yali; Chen, Yuewen; Gao, Shufang

2015-01-01

An attractive method of generating second-order data was developed by a dropping technique to generate pH gradient simultaneously coupled with diode-array spectrophotometer scanning. A homemade apparatus designed for the pH gradient. The method and the homemade apparatus were used to simultaneously determine malachite green (MG) and crystal violet (CV) in water samples. The absorbance-pH second-order data of MG or CV were obtained from the spectra of MG or CV in a series of pH values of HCl-KCl solution. The second-order data of mixtures containing MG and CV that coexisted with interferents were analyzed using multidimensional partial least-squares with residual bilinearization. The method and homemade apparatus were used to simultaneously determine MG and CV in fish farming water samples and in river ones with satisfactory results. The presented method and the homemade apparatus could serve as an alternative tool to handle some analysis problems. Copyright © 2015 Elsevier B.V. All rights reserved.

Simultaneous Adsorption and Photocatalytic Degradation of Malachite Green Using Electrospun P(3HB-TiO2 Nanocomposite Fibers and Films

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Nanthini Sridewi

2011-01-01

Full Text Available This paper demonstrated the applicability of electrospun P(3HB film as a dye adsorbent agent. Malachite green (MG was used as the model dye in this study. Interestingly, the electrospun P(3HB film exhibited excellent dye adsorption capacity whereby 78% of dye was adsorbed from a 30 μM solution of MG. The film was further improvised by incorporating titanium dioxide photocatalysts to form a dual dye treatment system employing adsorption and photocatalytic degradation techniques. The resultant electrospun P(3HB-50 wt%   TiO2 was capable of completely decolorizing MG in 45 min under solar irradiation, which corresponded to 58.7%  COD removal. The fully decolorized MG solution also proved to be nontoxic against A. aegypti mosquito larvae. The reapplicability of this film was possible as it induced a decolorization rate of 98% or more at every usage for ten consequent usages. EDX analysis suggested that there were no significant changes in the concentration of titanium (Ti in the film before and after ten times of usage. The concentration of Ti in cast P(3HB-50 wt%  TiO2 film was found to decrease significantly during the repeated usage. The electrospun P(3HB-50 wt%  TiO2 film has high potency as an efficient and inexpensive yet simple method for the dye effluent decolorization, degradation, and detoxification.

Degradation and detoxification of the triphenylmethane dye malachite green catalyzed by crude manganese peroxidase from Irpex lacteus F17.

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Yang, Xueting; Zheng, Jinzhao; Lu, Yongming; Jia, Rong

2016-05-01

Malachite green (MG), a recalcitrant, carcinogenic, and mutagenic triphenylmethane dye, was decolorized and detoxified using crude manganese peroxidase (MnP) prepared from the white rot fungus Irpex lacteus F17. In this study, the key factors (pH, temperature, MG, Mn(2+), H2O2, MnP) in these processes were investigated. Under optimal conditions, 96 % of 200 mg L(-1) of MG was decolorized when 66.32 U L(-1) of MnP was added for 1 h. The K m, V max, and k cat values were 109.9 μmol L(-1), 152.8 μmol L(-1) min(-1), and 44.5 s(-1), respectively. The decolorization of MG by MnP followed first-order reaction kinetics with a kinetic rate constant of 0.0129 h(-1). UV-vis and UPLC analysis revealed degradation of MG. Furthermore, seven different intermediates formed during the MnP treatment of 0.5 h were identified by LC-TOF-MS. These degradation products were generated via two different routes by either N-demethylation of MG or the oxidative cleavage of the C-C double bond in MG. Based on ecotoxicity analyses performed on bacteria and algae, it was confirmed that MG metabolites produced by the MnP-catalyzed system were appreciably less toxic than the parent compound. These studies indicate the potential use of this enzyme system in the clean-up of aquatic and terrestrial environments.

Structure defects in malachite revealed by positron annihilation

International Nuclear Information System (INIS)

Geffroy, B.; Diallo, I.; Paulin, R.

1984-01-01

Positron lifetime is measured between 77 and 400 K in two malachite samples with different mineralogical structures. The complex spectrum found in zoned malachite reveals a microporosity which remains stable in this range of temperature. Besides, above 200 K, equilibrium defects appear. Their formation energy is estimated to be Esub(f) = 0.27 +- 0.02 eV [fr

Structure defects in malachite revealed by positron annihilation

Energy Technology Data Exchange (ETDEWEB)

Geffroy, B; Diallo, I; Paulin, R [Institut National des Sciences et Techniques Nucleaires, CEN/Saclay, 91 - Gif-sur-Yvette (France)

1984-01-01

Positron lifetime is measured between 77 and 400 K in two malachite samples with different mineralogical structures. The complex spectrum found in zoned malachite reveals a microporosity which remains stable in this range of temperature. Besides, above 200 K, equilibrium defects appear. Their formation energy is estimated to be Esub(f) = 0.27 +- 0.02 eV.

Surface modification of malachite with ethanediamine and its effect on sulfidization flotation

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Feng, Qicheng; Zhao, Wenjuan; Wen, Shuming

2018-04-01

Ethanediamine was used to modify the mineral surface of malachite to improve its sulfidization and flotation behavior. The activation mechanism was investigated by adsorption experiments, X-ray photoelectron spectroscopy (XPS) analysis, and zeta potential measurements. Microflotation experiments showed that the flotation recovery of malachite was enhanced after the pretreatment of the mineral particles with ethanediamine prior to the addition of Na2S. Adsorption tests revealed that numerous sulfide ion species in the pulp solution were transferred onto the mineral surface through the formation of more copper sulfide species. This finding was confirmed by the results of the XPS measurements. Ethanediamine modification not only increased the contents of copper sulfide species on the malachite surface but also enhanced the reactivity of the sulfidization products. During sulfidization, Cu(II) species on the mineral surface were reduced into Cu(I) species, and the percentages of S22- and Sn2- relative to the total S increased after modification, resulting in increased surface hydrophobicity. The results of zeta potential measurements showed that the ethanediamine-modified mineral surface adsorbed with more sulfide ion species was advantageous to the attachment of xanthate species, thereby improving malachite floatability. The proposed ethanediamine modification followed by sulfidization xanthate flotation exhibits potential for industrial application.

Central composite design and genetic algorithm applied for the optimization of ultrasonic-assisted removal of malachite green by ZnO Nanorod-loaded activated carbon

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Ghaedi, M.; Azad, F. Nasiri; Dashtian, K.; Hajati, S.; Goudarzi, A.; Soylak, M.

2016-10-01

Maximum malachite green (MG) adsorption onto ZnO Nanorod-loaded activated carbon (ZnO-NR-AC) was achieved following the optimization of conditions, while the mass transfer was accelerated by ultrasonic. The central composite design (CCD) and genetic algorithm (GA) were used to estimate the effect of individual variables and their mutual interactions on the MG adsorption as response and to optimize the adsorption process. The ZnO-NR-AC surface morphology and its properties were identified via FESEM, XRD and FTIR. The adsorption equilibrium isotherm and kinetic models investigation revealed the well fit of the experimental data to Langmuir isotherm and pseudo-second-order kinetic model, respectively. It was shown that a small amount of ZnO-NR-AC (with adsorption capacity of 20 mg g- 1) is sufficient for the rapid removal of high amount of MG dye in short time (3.99 min).

Use of Malachite Green-Loop Mediated Isothermal Amplification for Detection of Plasmodium spp. Parasites

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Lucchi, Naomi W.; Ljolje, Dragan; Silva-Flannery, Luciana; Udhayakumar, Venkatachalam

2016-01-01

Malaria elimination efforts are hampered by the lack of sensitive tools to detect infections with low-level parasitemia, usually below the threshold of standard diagnostic methods, microscopy and rapid diagnostic tests. Isothermal nucleic acid amplification assays such as the loop-mediated isothermal amplification (LAMP), are well suited for field use as they do not require thermal cyclers to run the test. However, the use of specialized equipment, as described by many groups, reduces the versatility of the LAMP technique as a simple tool for use in endemic countries. In this study, the use of the malachite green (MG) dye, as a visual endpoint readout, together with a simple mini heat block was evaluated for the detection of malaria parasites. The assay was performed for 1 hour at 63°C and the results scored by 3 independent human readers. The limit of detection of the assay was determined using well-quantified Plasmodium spp. infected reference samples and its utility in testing clinical samples was determined using 190 pre-treatment specimens submitted for reference diagnosis of imported malaria in the United States. Use of a simplified boil and spin methods of DNA extraction from whole blood and filter paper was also investigated. We demonstrate the accurate and sensitive detection of malaria parasites using this assay with a detection limit ranging between 1–8 parasites/μL, supporting its applicability for the detection of infections with low parasite burden. This assay is compatible with the use of a simple boil and spin sample preparation method from both whole blood and filter papers without a loss of sensitivity. The MG-LAMP assay described here has great potential to extend the reach of molecular tools to settings where they are needed. PMID:26967908

Use of Malachite Green-Loop Mediated Isothermal Amplification for Detection of Plasmodium spp. Parasites.

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Naomi W Lucchi

Full Text Available Malaria elimination efforts are hampered by the lack of sensitive tools to detect infections with low-level parasitemia, usually below the threshold of standard diagnostic methods, microscopy and rapid diagnostic tests. Isothermal nucleic acid amplification assays such as the loop-mediated isothermal amplification (LAMP, are well suited for field use as they do not require thermal cyclers to run the test. However, the use of specialized equipment, as described by many groups, reduces the versatility of the LAMP technique as a simple tool for use in endemic countries. In this study, the use of the malachite green (MG dye, as a visual endpoint readout, together with a simple mini heat block was evaluated for the detection of malaria parasites. The assay was performed for 1 hour at 63°C and the results scored by 3 independent human readers. The limit of detection of the assay was determined using well-quantified Plasmodium spp. infected reference samples and its utility in testing clinical samples was determined using 190 pre-treatment specimens submitted for reference diagnosis of imported malaria in the United States. Use of a simplified boil and spin methods of DNA extraction from whole blood and filter paper was also investigated. We demonstrate the accurate and sensitive detection of malaria parasites using this assay with a detection limit ranging between 1-8 parasites/μL, supporting its applicability for the detection of infections with low parasite burden. This assay is compatible with the use of a simple boil and spin sample preparation method from both whole blood and filter papers without a loss of sensitivity. The MG-LAMP assay described here has great potential to extend the reach of molecular tools to settings where they are needed.

Comparative use of anodic oxidation, electro-Fenton and photoelectro-Fenton with Pt or boron-doped diamond anode to decolorize and mineralize Malachite Green oxalate dye

International Nuclear Information System (INIS)

El-Ghenymy, Abdellatif; Centellas, Francesc; Rodríguez, Rosa María; Cabot, Pere Lluís; Garrido, José Antonio; Sirés, Ignasi; Brillas, Enric

2015-01-01

Highlights: • Degradation of Malachite Green oxalate solutions at pH 3.0 by AO, AO-H 2 O 2 , EF and PEF. • A Pt anode leads to slower decolorization and mineralization than BDD. • Up to 97% mineralization by the most powerful PEF process with BDD at 100 mA cm −2 . • Study of the evolution of seven final short-chain aliphatic carboxylic acids. • Conversion of the initial N atoms of the dye mainly into NH 4 + , along with small amounts of NO 3 − . - Abstract: The degradation of 100 cm 3 of 177 mg dm −3 of the triphenylmethane dye Malachite Green oxalate at pH 3.0 was studied by anodic oxidation with stainless steel cathode (AO-SS), AO with air-diffusion cathode (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF) with UVA light. The main oxidizing species were hydroxyl radicals formed from either water oxidation at the anode surface or in the bulk between added Fe 2+ and H 2 O 2 generated at the air-diffusion cathode. The use of a Pt anode led to slower decolorization and mineralization than BDD in all treatments because of the higher oxidation power of the latter. The decolorization was much faster for EF and PEF compared to AO-SS and AO-H 2 O 2 due to the contribution of hydroxyl radicals in the bulk. PEF allowed the quickest color removal by the rapid Fe 2+ regeneration from the photolysis of Fe(III) complexes with oxalate. The most powerful process was PEF with BDD, which yielded total decolorization in 6 min and 97% mineralization at 240 min operating at 100 mA cm −2 , thanks to hydroxyl radicals formed at the anode surface and in the bulk along with the photolytic action of UVA radiation. The evolution of final carboxylic acids like maleic, fumaric, succinic, acetic, oxalic, formic and oxamic was followed by ion-exclusion HPLC. All these acids and their Fe(III) complexes were removed more slowly with Pt anode. The initial N atoms of the dye were pre-eminently accumulated as NH 4 + ion, along with small amounts of NO 3 − ion.

Double-shell Fe2O3 hollow box-like structure for enhanced photo-Fenton degradation of malachite green dye

Science.gov (United States)

Jiang, De Bin; Liu, Xiaoying; Xu, Xuan; Zhang, Yu Xin

2018-01-01

In this work we demonstrate the synthesis of novel Fe2O3 nanosheets with double-shell hollow morphology by replica molding from diatomite framework. The nanostructures of Fe2O3 nanosheets were examined by focused-ion-beam scanning electron microscopy (FIB/SEM), X-ray diffraction spectroscopy (XRD), Brunauer-Emmett-Teller (BET) specific surface area measurements and Fourier transform infrared (FT-IR) spectroscopy. The results reveal that (1) Pure Fe2O3 nanosheets were successfully obtained; (2) The double-shell Fe2O3 hollow structure achieved via the NaOH etching silica method was observed; (3) Fe2O3 nanosheets possessed uniformly distributed porous nanosheets. Such structural features enlarged the specific surface area of Fe2O3 nanosheets and led to more catalytic active sites. In the heterogeneous photo-Fenton reaction, the double-shell Fe2O3 hollow morphology exhibited excellent catalytic capability for the degradation of malachite green (MG) at circumneutral pH condition. Under optimum condition, MG solution was almost completely decolorized in 60 min (99.9%). The Fe2O3 nanosheets also showed good stability and recyclability, demonstrating great potential as a promising photo-Fenton catalyst for the effective degradation of MG dye in wastewater.

Enhancing adsorption capacity of toxic malachite green dye through chemically modified breadnut peel: equilibrium, thermodynamics, kinetics and regeneration studies.

Science.gov (United States)

Chieng, Hei Ing; Lim, Linda B L; Priyantha, Namal

2015-01-01

Breadnut skin, in both its unmodified (KS) and base-modified (BM-KS) forms, was investigated for its potential use as a low-cost adsorbent for the removal of toxic dye, malachite green (MG). Characterization of the adsorbents was carried out using scanning electron microscope, X-ray fluorescence and Fourier transform infra-red spectroscopy. Batch adsorption experiments, carried out under optimized conditions, for the adsorption of MG were fitted using five isotherm models (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin and Sips) and six error functions to determine the best-fit model. The adsorption capacity was greatly enhanced when breadnut skin was chemically modified with NaOH, leading to an adsorption capacity of 353.0 mg g(-1), that was far superior to most reported adsorbents for the removal of MG. Thermodynamics studies indicated that the adsorption of MG was spontaneous on KS and BM-KS, and the reactions were endothermic and exothermic, respectively. Kinetics studies showed that both followed the pseudo-second order. Regeneration experiments on BM-KS indicated that its adsorption capacity was still maintained at>90% even after five cycles. It can be concluded that NaOH-modified breadfruit skin has great potential to be utilized in real-life application as a low-cost adsorbent for the removal of MG in wastewater treatment.

Fabrication of Ag-decorated BiOBr-mBiVO4 dual heterojunction composite with enhanced visible light photocatalytic performance for degradation of malachite green

Science.gov (United States)

Regmi, Chhabilal; Dhakal, Dipesh; Kim, Tae-Ho; Yamaguchi, Takutaro; Wohn Lee, Soo

2018-04-01

A visible light active Ag-decorated BiVO4-BiOBr dual heterojunction photocatalyst was prepared using a facile hydrothermal method, followed by the photodeposition of Ag. The photocatalytic activity of the synthesized samples was investigated by monitoring the change in malachite green (MG) concentration upon visible light irradiation. The synthesized sample was highly effective for the degradation of non-biodegradable MG. The enhanced activity observed was ascribed to the efficient separation and transfer of charge carriers across the dual heterojunction structure as verified by photoluminescence measurements. The removal of MG was primarily initiated by hydroxyl radicals and holes based on scavenger’s effect. To gain insight into the degradation mechanism, both high performance liquid chromatography and high resolution-quantitative time of flight, electrospray ionization mass spectrometry measurements during the degradation process were carried out. The degradation primarily followed the hydroxylation and N-demethylation process. A possible reaction pathway is proposed on the basis of all the information obtained under various experimental conditions.

Ultra-high adsorption capacity of zeolitic imidazole framework-67 (ZIF-67) for removal of malachite green from water.

Science.gov (United States)

Lin, Kun-Yi Andrew; Chang, Hsuan-Ang

2015-11-01

Zeolitic imidazole frameworks (ZIFs), a new class of adsorbents, are proposed to adsorb Malachite Green (MG) in water. Particularly, ZIF-67 was selected owing to its stability in water and straightforward synthesis. The as-synthesized ZIF-67 was characterized and used to adsorb MG from water. Factors affecting the adsorption capacity were investigated including mixing time, temperature, the presence of salts and pH. The kinetics, adsorption isotherm and thermodynamics of the MG adsorption to ZIF-67 were also studied. The adsorption capacity of ZIF-67 for MG could be as high as 2430mgg(-1) at 20°C, which could be improved at the higher temperatures. Such an ultra-high adsorption capacity of ZIF-67 was almost 10-times of those of conventional adsorbents, including activated carbons and biopolymers. A mechanism for the high adsorption capacity was proposed and possibly attributed to the π-π stacking interaction between MG and ZIF-67. ZIF-67 also could be conveniently regenerated by washing with ethanol and the regeneration efficiency could remain 95% up to 4 cycles of the regeneration. ZIF-67 was also able to remove MG from the aquaculture wastewater, in which MG can be typically found. These features enable ZIF-67 to be one of the most effective and promising adsorbent to remove MG from water. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design of binary SnO_2-CuO nanocomposite for efficient photocatalytic degradation of malachite green dye

International Nuclear Information System (INIS)

Kumar, Aniket; Rout, Lipeeka; Achary, L. Satish Kumar; Mohanty, Anurag; Marpally, Jyoshna; Chand, Pradyumna Kumar; Dash, Priyabrat

2016-01-01

Semiconductor mediated photocatalysis has got enormous consideration as it has shown immense potential in addressing the overall energy and environmental issues. To overcome the earlier drawbacks concerning quick charge recombination and limited visible-light absorption of semiconductor photocatalysts, numerous methods have been produced in the past couple of decades and the most broadly utilized one is to develop the photocatalytic heterojunctions. In our work, a series of SnO_2-CuO nanocomposites of different compositions were synthesized by a combustion method and have been investigated in detail by various characterization techniques, such as wide angle X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The results revealed that the crystal structure and optical properties of the nanocomposites were almost same for all the compositions. FE-SEM images showed that the shape of SnO_2-CuO was spherical in nature and the 1: 1 Sn/Cu sample had a well-proportioned morphology. The malachite green dye was used for the photocatalytic studies in a photoreactor and monitored with a UV-visible spectrometer for different composition ratio of metal (Sn: Cu) such as 1:1, 1:2, 2:1, 1:0.5 and 0.5:1. The 1:1 ratio nanocomposite showed excellent photocatalytic degradation of 96 % compared to pure SnO_2 and CuO. The mechanism of degradation and charge separation ability of the nanocomposite are also explored using photocurrent measurement study.

Removal of malachite green dye from aqueous solution with adsorption technique using Limonia acidissima (wood apple shell as low cost adsorbent

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Ashish S. Sartape

2017-05-01

Full Text Available In the present study, the use of low-cost, abundantly available, highly efficient and eco-friendly adsorbent wood apple shell (WAS has been reported as an alternative to the current expensive methods of removing of malachite green (MG dye from aqueous solution. The effects of different variables, adsorbent dosage, initial dye concentration, pH, contact time, temperature etc. were investigated and optimal experimental conditions were ascertained. The Langmuir isotherm model has given a better conformity than the Freundlich model with 80.645 mg/g as maximum adsorption capacity at 299 K. The adsorption of MG on WAS was confirmed by FTIR, SEM study, as it showed the change in characterization before and after adsorption. It was found that the Lagergren’s model could be used for the prediction of the system’s kinetics, while intraparticle diffusion study and Boyd plot were used to furnish the mechanistic study. Thermodynamic study concluded the spontaneous and endothermic nature of the adsorption. Present investigation and comparison with other reported adsorbents concluded that, WAS may be applied as a low-cost attractive option for removal of MG from aqueous solution.

Detection of malachite green in fish based on magnetic fluorescent probe of CdTe QDs/nano-Fe3O4@MIPs

Science.gov (United States)

Wu, Le; Lin, Zheng-Zhong; Zeng, Jun; Zhong, Hui-Ping; Chen, Xiao-Mei; Huang, Zhi-Yong

2018-05-01

A magnetic fluorescent probe of CdTe QDs/nano-Fe3O4@MIPs was prepared using CdTe QDs and Fe3O4 nanoparticles as co-nucleus and molecularly imprinted polymers (MIPs) as specific recognition sites based on a reverse microemulsion method. With the specific enrichment and magnetic separation properties, the probe of CdTe QDs/nano-Fe3O4@MIPs was used to detect malachite green (MG) in fish samples. The TEM analysis showed that the particles of CdTe QDs/nano-Fe3O4@MIPs were spherical with average diameter around 53 nm, and a core-shell structure was well-shaped with several Fe3O4 nanoparticles and CdTe QDs embedded in each of the microsphere. Quick separation of the probes from solutions could be realized with a magnet, indicating the excellent magnetic property of CdTe QDs/nano-Fe3O4@MIPs. The probe exhibited high specific adsorption towards MG and excellent fluorescence emission at λem 598 nm. The fluorescence of CdTe QDs/nano-Fe3O4@MIPs could be linearly quenched by MG at the concentrations from 0.025 to 1.5 μmol L-1. The detection limit was 0.014 μmol L-1. The average recovery of spiked MG in fish samples was 105.2%. The result demonstrated that the as-prepared CdTe QDs/nano-Fe3O4@MIPs could be used as a probe to the detection of trace MG in fish samples.

Synthesis of magnetic mesoporous metal-organic framework-5 for the effective enrichment of malachite green and crystal violet in fish samples.

Science.gov (United States)

Zhou, Zhihui; Fu, Yanqing; Qin, Qian; Lu, Xin; Shi, Xianzhe; Zhao, Chunxia; Xu, Guowang

2018-07-27

A novel, magnetic and mesoporous Fe 3 O 4 @PEI-MOF-5 material was synthesized for the effective enrichment of malachite green (MG) and crystal violet (CV) in fish samples. The Fe 3 O 4 @PEI-MOF-5 material was prepared by a facile two-step solvothermal approach in which Fe 3 O 4 @PEI and MOF-5 were connected through chemical bonds. Characterization of the newly synthesized Fe 3 O 4 @PEI-MOF-5 material was performed by Fourier transform infrared spectroscopy, X-ray diffractometry, vibrating sample magnetometry, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis and X-ray photoelectron spectroscopy. This new material was determined to have high magnetization and chemical stability, a large surface area and a distinctive morphology. An effective enrichment and detection method for MG and CV was subsequently developed by combining the Fe 3 O 4 @PEI-MOF-5 material with ultra-high-performance liquid chromatography-tandem mass spectrometry. The linearity ranges of this approach for MG and CV were 1-500ng/mL and 0.25-500ng/mL, respectively, with correlation coefficients (R 2 ) of 0.999. The limits of detection (LODs) of the method for MG and CV were 0.30ng/mL and 0.08ng/mL, respectively, indicating that the Fe 3 O 4 @PEI-MOF-5 material had good adsorption properties for MG and CV. Fe 3 O 4 @PEI-MOF-5 can be expected to also provide efficient enrichment of MG and CV in other complex matrices. Copyright © 2018 Elsevier B.V. All rights reserved.

Batch adsorption technique for the removal of malachite green and ...

African Journals Online (AJOL)

hope&shola

2010-11-29

Nov 29, 2010 ... 2001), used tea leaves. (Tahir et al., 2009), montmorillonite clay powder (Tahir et al., 2008), algea (Tahir et al., 2008) which can be utili- zed to remove dyes and colorants from waste water. Fast green FCF is a sea green triarylmethane food color dye, which is also known as food green with maxi- ...

Synthesis of Copper Pigments, Malachite and Verdigris: Making Tempera Paint

Science.gov (United States)

Solomon, Sally D.; Rutkowsky, Susan A.; Mahon, Megan L.; Halpern, Erica M.

2011-01-01

Malachite and verdigris, two copper-based pigments, are synthesized in this experiment intended for use in a general chemistry laboratory. The preparation of egg tempera paint from malachite is also described. All procedures can be done with a magnetic stir plate, standard glassware present in any first-year laboratory, and household chemicals.…

A versatile SERS-based immunoassay for immunoglobulin detection using antigen-coated gold nanoparticles and malachite green-conjugated protein A/G

Science.gov (United States)

A surface enhanced Raman scattering (SERS) immunoassay for antibody detection in serum is described in the present work. The developed assay is conducted in solution and utilizes Au nanoparticles coated with the envelope (E) protein of West Nile Virus (WNV) as the SERS-active substrate and malachite...

Effect of COOH-functionalized SWCNT addition on the electrical and photovoltaic characteristics of Malachite Green dye based photovoltaic cells

International Nuclear Information System (INIS)

Chakraborty, S.; Manik, N. B.

2014-01-01

We report the effect of COOH-functionalized single walled carbon nanotubes (COOH-SWCNT) on the electrical and photovoltaic characteristics of Malachite Green (MG) dye based photovoltaic cells. Two different types of photovoltaic cells were prepared, one with MG dye and another by incorporating COOH-SWCNT with this dye. Cells were characterized through different electrical and photovoltaic measurements including photocurrent measurements with pulsed radiation. From the dark current—voltage (I–V) characteristic results, we observed a certain transition voltage (V th ) for both the cells beyond which the conduction mechanism of the cells change sharply. For the MG dye, V th is 3.9 V whereas for COOH-SWCNT mixed with this dye, V th drops to 2.7 V. The device performance improves due to the incorporation of COOH-SWCNT. The open circuit voltage and short circuit current density change from 4.2 to 97 mV and from 108 to 965 μA/cm 2 respectively. Observations from photocurrent measurements show that the rate of growth and decay of the photocurrent are quite faster in the presence of COOH-SWCNT. This observation indicates a faster charge separation processes due to the incorporation of COOH-SWCNT in the MG dye cells. The high aspect ratio of COOH-SWCNT allows efficient conduction pathways for the generated charge carriers. (semiconductor devices)

Extraction/spectrophotometric determination of molybdenum(VI) with 4,6-di-t-butyl-3-methoxycatechol and Malachite Green

Energy Technology Data Exchange (ETDEWEB)

Oshima, Mitsuko; Nishizaki, Youko; Motomizu, Shoji

1988-10-01

Mo(VI) forms an chelate anion with 4,6-di-t-butyl-3-methoxycatechol (DBMC) and the ion asscoiate between the chelate anion and Malachite Green (MG) is extracted into toluene in the pH range from 1.8 to 3.5. DBMC was synthesized according to our previous work. The standard procedure was as follows: transfer a sample solution /Mo (VI) < 4.8 /mu/g/ into a 25 ml test tube with stopper, and add 0.5 ml each of 5 x 10/sup -2/ M sulfuric acid and 1.0 x 10/sup -3/ M MG solution. If necessary, add masking agent solution (ascorbic acid and tartaric acid). After adding water to make up to 10 ml, add 5 ml of 1.5 x 10/sup -2/ M DBMC toluene solution, then shake for 30 min. Measure the absorbance of the organic phase at 635 nm. Apparent molar absorptivity was 8.0 x 10/sup 4/ l mol/sup -1/ cm/sup -1/ and the absorbance of the reagent blank was 0.01. The relative standard deviation of 10 measurements of 1.92 ..mu..g of Mo(VI) was 0.52 %. The present method was applied to steel samples with satisfactory results. The effect of W(VI) coexisting at concentrations over 1 x 10/sup -6/ M was corrected by the equations using apparent molar absorptivities of Mo(VI) and W(VI) obtained with or without the masking agent (2.5 x 10/sup -3/ M tartaric acid).

Poly(malachite green) at nafion doped multi-walled carbon nanotube composite film for simple aliphatic alcohols sensor.

Science.gov (United States)

Umasankar, Yogeswaran; Periasamy, Arun Prakash; Chen, Shen-Ming

2010-01-15

Conductive composite film which contains nafion (NF) doped multi-walled carbon nanotubes (MWCNTs) along with the incorporation of poly(malachite green) (PMG) has been synthesized on glassy carbon electrode (GCE), gold and indium tin oxide (ITO) electrodes by potentiostatic methods. The presence of MWCNTs in the composite film (MWCNTs-NF-PMG) enhances surface coverage concentration (Gamma) of PMG to approximately 396%, and increases the electron transfer rate constant (k(s)) to approximately 305%. Similarly, electrochemical quartz crystal microbalance study reveals the enhancement in the deposition of PMG at MWCNTs-NF film. The surface morphology of the composite film deposited on ITO electrode has been studied using scanning electron microscopy (SEM) and scanning tunneling microscopy (STM). These two techniques reveal that the PMG incorporated on MWCNTs-NF film. The MWCNTs-NF-PMG composite film also exhibits promising enhanced electrocatalytic activity towards the simple aliphatic alcohols such as methanol, ethanol and propanol. The electroanalytical responses of analytes at NF-PMG and MWCNTs-NF-PMG films were measured using both cyclic voltammetry (CV) and differential pulse voltammetry (DPV). From electroanalytical studies, well defined voltammetric peaks have been obtained at MWCNTs-NF-PMG composite film for methanol, ethanol and propanol at Epa=609, 614 and 602mV respectively. The sensitivity of MWCNTs-NF-PMG composite film towards methanol, ethanol and propanol in CV technique are 0.59, 0.36 and 0.92microAmM(-1)cm(-2) respectively, which are higher than NF-PMG film. Further, the sensitivity values obtained using DPV are higher than the values obtained using CV technique.

Activation mechanism of ammonium ions on sulfidation of malachite (-201) surface by DFT study

Science.gov (United States)

Wu, Dandan; Mao, Yingbo; Deng, Jiushuai; Wen, Shuming

2017-07-01

The activation mechanism of ammonium ions on the sulfidation of malachite (-201) was determined by density functional theory (DFT) calculations. Results of DFT calculations indicated that interlayer sulfidation occurs during the sulfidation process of malachite (-201). The absorption of both the ammonium ion and sulfide ion on the malachite (-201) surface is stronger than that of sulfur ion. After sulfidation was activated with ammonium ion, the Cu 3d orbital peak is closer to the Fermi level and characterized by a stronger peak value. Therefore, the addition of ammonium ions activated the sulfidation of malachite (-201), thereby improving the flotation performance.

Efficient Photocatalytic Degradation of Malachite Green in Seawater by the Hybrid of Zinc-Oxide Nanorods Grown on Three-Dimensional (3D Reduced Graphene Oxide(RGO/Ni Foam

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Qing Wang

2018-06-01

Full Text Available A hybrid of ZnO nanorods grown onto three-dimensional (3D reduced graphene oxide (RGO@Ni foam (ZnO/RGO@NF is synthesized by a facile hydrothermal method. The as-prepared hybrid material is physically characterized by SEM, XRD, Raman, and X-ray photoelectron spectroscopy (XPS. When the as-prepared 3D hybrid is investigated as a photocatalyst, it demonstrates significant high photocatalytic activity for the degradation of methylene blue (MB, rhodamine (RhB, and mixed MB/RhB as organic dye pollutants. In addition, the practical application and the durability of the as-prepared catalyst to degradation of malachite green (MG in seawater are firstly assessed in a continuous flow system. The catalyst shows a high degradation efficiency and stable photocatalytic activity for 5 h continuous operation, which should be a promising catalyst for the degradation of organic dyes in seawater.

Interaction of malachite green with bovine serum albumin: Determination of the binding mechanism and binding site by spectroscopic methods

International Nuclear Information System (INIS)

Zhang Yezhong; Zhou Bo; Zhang Xiaoping; Huang Ping; Li Chaohong; Liu Yi

2009-01-01

The interaction between malachite green (MG) and bovine serum albumin (BSA) under simulative physiological conditions was investigated by the methods of fluorescence spectroscopy, UV-vis absorption and circular dichroism (CD) spectroscopy. Fluorescence data showed that the fluorescence quenching of BSA by MG was the result of the formation of the MG-BSA complex. According to the modified Stern-Volmer equation, the effective quenching constants (K a ) between MG and BSA at four different temperatures were obtained to be 3.734 x 10 4 , 3.264 x 10 4 , 2.718 x 10 4 , and 2.164 x 10 4 L mol -1 , respectively. The enthalpy change (ΔH) and entropy change (ΔS) were calculated to be -27.25 kJ mol -1 and -11.23 J mol -1 K -1 , indicating that van der Waals force and hydrogen bonds were the dominant intermolecular force in stabilizing the complex. Site marker competitive experiments indicated that the binding of MG to BSA primarily took place in sub-domain IIA. The binding distance (r) between MG and the tryptophan residue of BSA was obtained to be 4.79 nm according to Foerster theory of non-radioactive energy transfer. The conformational investigation showed that the presence of MG decreased the α-helical content of BSA (from 62.6% to 55.6%) and induced the slight unfolding of the polypeptides of protein, which confirmed some micro-environmental and conformational changes of BSA molecules

Photocatalytic performance of Sn-doped TiO2 nanostructured mono and double layer thin films for Malachite Green dye degradation under UV and vis-lights

International Nuclear Information System (INIS)

Sayilkan, F.; Asiltuerk, M.; Tatar, P.; Kiraz, N.; Arpac, E.; Sayilkan, H.

2007-01-01

Nanostructure Sn 4+ -doped TiO 2 based mono and double layer thin films, contain 50% solid ratio of TiO 2 in coating have been prepared on glass surfaces by spin-coating technique. Their photocatalytic performances were tested for degradation of Malachite Green dye in solution under UV and vis irradiation. Sn 4+ -doped nano-TiO 2 particle a doping ratio of about 5[Sn 4+ /Ti(OBu n ) 4 ; mol/mol%] has been synthesized by hydrotermal process at 225 deg. C. The structure, surface and optical properties of the thin films and/or the particles have been investigated by XRD, BET and UV/vis/NIR techniques. The results showed that the double layer coated glass surfaces have a very high photocatalytic performance than the other one under UV and vis lights. The results also proved that the hydrothermally synthesized nano-TiO 2 particles are fully anatase crystalline form and are easily dispersed in water. The results also reveal that the coated surfaces have hydrophilic property

Decolorization and degradation of malachite green by Aspergillus ...

African Journals Online (AJOL)

Bioremediation using a variety of microbes for the degradation of xenobiotics seems a green solution to the problem of environmental pollution. Microbes have been gifted by nature with the ability of degrading a wide spectrum of environmental pollutants. Different fungi have the potentials to degrade complex and ...

Combining Pickering Emulsion Polymerization with Molecular Imprinting to Prepare Polymer Microspheres for Selective Solid-Phase Extraction of Malachite Green

Directory of Open Access Journals (Sweden)

Weixin Liang

2017-08-01

Full Text Available Malachite green (MG is currently posing a carcinogenic threat to the safety of human lives; therefore, it is highly desirable to develop an effective method for fast trace detection of MG. Herein, for the first time, this paper presents a systematic study on polymer microspheres, being prepared by combined Pickering emulsion polymerization and molecular imprinting, to detect and purify MG. The microspheres, molecularly imprinted with MG, show enhanced adsorption selectivity to MG, despite a somewhat lowered adsorption capacity, as compared to the counterpart without molecular imprinting. Structural features and adsorption performance of these microspheres are elucidated by different characterizations and kinetic and thermodynamic analyses. The surface of the molecularly imprinted polymer microspheres (M-PMs exhibits regular pores of uniform pore size distribution, endowing M-PMs with impressive adsorption selectivity to MG. In contrast, the microspheres without molecular imprinting show a larger average particle diameter and an uneven porous surface (with roughness and a large pore size, causing a lower adsorption selectivity to MG despite a higher adsorption capacity. Various adsorption conditions are investigated, such as pH and initial concentration of the solution with MG, for optimizing the adsorption performance of M-PMs in selectively tackling MG. The adsorption kinetics and thermodynamics are deeply discussed and analyzed, so as to provide a full picture of the adsorption behaviors of the polymer microspheres with and without the molecular imprinting. Significantly, M-PMs show promising solid-phase extraction column applications for recovering MG in a continuous extraction manner.

Interaction of malachite green with bovine serum albumin: Determination of the binding mechanism and binding site by spectroscopic methods

Energy Technology Data Exchange (ETDEWEB)

Zhang Yezhong [Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei 434023 (China); College of Chemistry and Molecular Sciences and State Key Laboratory of Virology, Wuhan University, Wuhan 430072 (China); Zhou Bo [College of Chemistry and Molecular Sciences and State Key Laboratory of Virology, Wuhan University, Wuhan 430072 (China); Zhang Xiaoping; Huang Ping [Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei 434023 (China); Li Chaohong [Education Ministry Key Laboratory for Oral Biomedical Engineering, School of Stomatology, Wuhan University, Wuhan 430072 (China); Liu Yi [Department of Chemistry, College of Chemistry and Environmental Engineering, Yangtze University, Jingzhou, Hubei 434023 (China) and College of Chemistry and Molecular Sciences and State Key Laboratory of Virology, Wuhan University, Wuhan 430072 (China)], E-mail: prof.liuyi@263.net

2009-04-30

The interaction between malachite green (MG) and bovine serum albumin (BSA) under simulative physiological conditions was investigated by the methods of fluorescence spectroscopy, UV-vis absorption and circular dichroism (CD) spectroscopy. Fluorescence data showed that the fluorescence quenching of BSA by MG was the result of the formation of the MG-BSA complex. According to the modified Stern-Volmer equation, the effective quenching constants (K{sub a}) between MG and BSA at four different temperatures were obtained to be 3.734 x 10{sup 4}, 3.264 x 10{sup 4}, 2.718 x 10{sup 4}, and 2.164 x 10{sup 4} L mol{sup -1}, respectively. The enthalpy change ({delta}H) and entropy change ({delta}S) were calculated to be -27.25 kJ mol{sup -1} and -11.23 J mol{sup -1} K{sup -1}, indicating that van der Waals force and hydrogen bonds were the dominant intermolecular force in stabilizing the complex. Site marker competitive experiments indicated that the binding of MG to BSA primarily took place in sub-domain IIA. The binding distance (r) between MG and the tryptophan residue of BSA was obtained to be 4.79 nm according to Foerster theory of non-radioactive energy transfer. The conformational investigation showed that the presence of MG decreased the {alpha}-helical content of BSA (from 62.6% to 55.6%) and induced the slight unfolding of the polypeptides of protein, which confirmed some micro-environmental and conformational changes of BSA molecules.

Cytotoxicity, genotoxicity and oxidative stress of malachite green on the kidney and gill cell lines of freshwater air breathing fish Channa striata.

Science.gov (United States)

Majeed, S Abdul; Nambi, K S N; Taju, G; Vimal, S; Venkatesan, C; Hameed, A S Sahul

2014-12-01

The cytotoxicity, genotoxicity and oxidative stress of malachite green (MG) was investigated using the fish Channa striata kidney (CSK) and Channa striata gill (CSG) cell lines. Five concentrations ranging from 0.001 to 10 μg mL(-1) were tested in three independent experiments. Cytotoxicity was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Rhodamine 123 and Alamar Blue. The mitochondrial changes and apoptosis of MG-exposed cells were observed by Rhodamine 123 and acridine orange/ethidium bromide (AO/EB) staining, respectively. In vitro potential DNA damaging effect of MG was tested using comet assay. Mitochondrial damage, apoptosis and DNA fragmentation increased in a concentration-dependent manner. Additionally, DNA electrophoretic mobility experiments were carried out to study the binding effect of MG to double-stranded DNA (dsDNA) of cells. DNA shift mobility experiments showed that MG is capable of strongly binding to linear dsDNA causing its degradation. Biochemical parameters such as lipid peroxidation (MDA), catalase (CAT) activity and reduced glutathione (GSH) levels were evaluated after exposure to MG. In CSK and CSG cell lines exposed to MG for 48 h, a significant increase in lipid peroxidation, which might be associated with decreased levels of reduced glutathione and catalase activity in these cell lines (p < 0.001), was observed.

Preparation of nanomaterials for the ultrasound-enhanced removal of Pb2+ ions and malachite green dye: Chemometric optimization and modeling.

Science.gov (United States)

Dil, Ebrahim Alipanahpour; Ghaedi, Mehrorang; Asfaram, Arash; Hajati, Shaaker; Mehrabi, Fatemeh; Goudarzi, Alireza

2017-01-01

Copper oxide nanoparticle-loaded activated carbon (CuO-NP-AC) was synthesized and characterized using different techniques such as FE-SEM, XRD and FT-IR. It was successfully applied for the ultrasound-assisted simultaneous removal of Pb 2+ ions and malachite green (MG) dye in binary system from aqueous solution. The effect of important parameters was modeled and optimized by artificial neural network (ANN) and response surface methodology (RSM). Maximum simultaneous removal percentages (>99.0%) were found at 25mgL -1 , 20mgL -1 , 0.02g, 5min and 6.0 corresponding to initial Pb 2+ concentration, initial MG concentration, CuO-NP-AC amount, ultrasonication time and pH, respectively. The precision of the equation obtained by RSM was confirmed by the analysis of variance and calculation of correlation coefficient relating the predicted and the experimental values of ultrasound-assisted simultaneous removal of the analytes. A good agreement between experimental and predicted values was observed. A feed-forward neural network with a topology optimized by response surface methodology was successfully applied for the prediction of ultrasound-assisted simultaneous removal of Pb 2+ ions and MG dye in binary system by CuO-NPs-AC. The number of hidden neurons, MSE, R 2 , number of epochs and error histogram were chosen for ANN modeling. Then, Langmuir, Freundlich, Temkin and D-R isothermal models were applied for fitting the experimental data. It was found that the Langmuir model well describes the isotherm data with a maximum adsorption capacity of 98.328 and 87.719mgg -1 for Pb 2+ and MG, respectively. Kinetic studies at optimum condition showed that maximum Pb 2+ and MG adsorption is achieved within 5min of the start of most experiments. The combination of pseudo-second-order rate equation and intraparticle diffusion model was applicable to explain the experimental data of ultrasound-assisted simultaneous removal of Pb 2+ and MG at optimum condition obtained from RSM

In Vitro Effect of Malachite Green on Candida albicans Involves Multiple Pathways and Transcriptional Regulators UPC2 and STP2

Science.gov (United States)

Dhamgaye, Sanjiveeni; Devaux, Frederic; Manoharlal, Raman; Vandeputte, Patrick; Shah, Abdul Haseeb; Singh, Ashutosh; Blugeon, Corinne; Sanglard, Dominique

2012-01-01

In this study, we show that a chemical dye, malachite green (MG), which is commonly used in the fish industry as an antifungal, antiparasitic, and antibacterial agent, could effectively kill Candida albicans and non-C. albicans species. We have demonstrated that Candida cells are susceptible to MG at a very low concentration (MIC that reduces growth by 50% [MIC50], 100 ng ml−1) and that the effect of MG is independent of known antifungal targets, such as ergosterol metabolism and major drug efflux pump proteins. Transcriptional profiling in response to MG treatment of C. albicans cells revealed that of a total of 207 responsive genes, 167 genes involved in oxidative stress, virulence, carbohydrate metabolism, heat shock, amino acid metabolism, etc., were upregulated, while 37 genes involved in iron acquisition, filamentous growth, mitochondrial respiration, etc., were downregulated. We confirmed experimentally that Candida cells exposed to MG resort to a fermentative mode of metabolism, perhaps due to defective respiration. In addition, we showed that MG triggers depletion of intracellular iron pools and enhances reactive oxygen species (ROS) levels. These effects could be reversed by the addition of iron or antioxidants, respectively. We provided evidence that the antifungal effect of MG is exerted through the transcription regulators UPC2 (regulating ergosterol biosynthesis and azole resistance) and STP2 (regulating amino acid permease genes). Taken together, our transcriptome, genetic, and biochemical results allowed us to decipher the multiple mechanisms by which MG exerts its anti-Candida effects, leading to a metabolic shift toward fermentation, increased generation of ROS, labile iron deprivation, and cell necrosis. PMID:22006003

A rapid molecular diagnosis of cutaneous leishmaniasis by colorimetric malachite green-loop-mediated isothermal amplification (LAMP) combined with an FTA card as a direct sampling tool.

Science.gov (United States)

Nzelu, Chukwunonso O; Cáceres, Abraham G; Guerrero-Quincho, Silvia; Tineo-Villafuerte, Edwin; Rodriquez-Delfin, Luis; Mimori, Tatsuyuki; Uezato, Hiroshi; Katakura, Ken; Gomez, Eduardo A; Guevara, Angel G; Hashiguchi, Yoshihisa; Kato, Hirotomo

2016-01-01

Leishmaniasis remains one of the world's most neglected diseases, and early detection of the infectious agent, especially in developing countries, will require a simple and rapid test. In this study, we established a quick, one-step, single-tube, highly sensitive loop-mediated isothermal amplification (LAMP) assay for rapid detection of Leishmania DNA from tissue materials spotted on an FTA card. An FTA-LAMP with pre-added malachite green was performed at 64°C for 60min using a heating block and/or water bath and DNA amplification was detected immediately after incubation. The LAMP assay had high detection sensitivity down to a level of 0.01 parasites per μl. The field- and clinic-applicability of the colorimetric FTA-LAMP assay was demonstrated with 122 clinical samples collected from patients suspected of having cutaneous leishmaniasis in Peru, from which 71 positives were detected. The LAMP assay in combination with an FTA card described here is rapid and sensitive, as well as simple to perform, and has great potential usefulness for diagnosis and surveillance of leishmaniasis in endemic areas. Copyright © 2015 Elsevier B.V. All rights reserved.

Hydrophobization og the surface fo malachite with some fluorosurfactants. 2,3 no fussokei kaimen kasseizai ni yoru malachite hyomen no sosuika

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, M [National Reserach Institute for Pollution and Resources, Tsukuba (Japan); Wakamatsu, T [Kyoto University, Kyoko (Japan). Faculty of Engineering

1991-10-18

The depleting trends of high-grade ores in recent years make it unavoidable to float ores in fine powder forms. To achieve this, research and development is important on such a recovering agent that can hydrophobize the surfaces of useful ores selectively and powerfully. This paper describes the discussion on three kinds of fluorosurfactant, namely perfluorooctanoic acid, Ftergent-100 and Ftergent-150, whic were used to hydrophobize the surface of malachite, and compared of its utilization possibility as a recovery agent with other surfactants. As a result, it was found that the Ftergent-100, which contains five CF{sub 3}{sup {minus}} in one molecule having extremely low critical surface tension, and the Ftergent-150 can hydrophobize sufficiently the malachite surface and provide good deposition. The region providing good deposition was at a weak-acidic to weak-alkali region in the case of the Ftergent-150. Therefore, both materials are thought they could be used as a recovering agent. 8 refs., 10 figs., 3 tabs.

Environmentally stable adsorbent of tetrahedral silica and non-tetrahedral alumina for removal and recovery of malachite green dye from aqueous solution

International Nuclear Information System (INIS)

Kannan, Chellapandian; Sundaram, Thiravium; Palvannan, Thayumanavan

2008-01-01

The conventional adsorbents like activated carbon, agricultural wastes, molecular sieves, etc., used for dye adsorption are unstable in the environment for long time, and hence the adsorbed dyes again gets liberated and pollute the environment. To avoid this problem, environmentally stable adsorbent of silica and alumina should be employed for malachite green adsorption. The adsorbents were characterized by Fourier transformed infrared spectroscopy (FT-IR) to confirm the tetrahedral framework of silica and non-tetrahedral framework of alumina. The adsorption equilibrium of dye on alumina and silica were 4 and 5 h, respectively, this less adsorption time on alumina might be due to the less activation energy on alumina (63.46 kJ mol -1 ) than silica (69.93 kJ mol -1 ). Adsorption increased with increase of temperature on silica, in alumina, adsorption increased up to 60 deg. C, and further increase of temperature decreased the adsorption due to the structural change of non-tetrahedral alumina in water. The optimum pH for dye adsorption on alumina was 5 and silica was 6. The dye adsorptions on both adsorbents followed pseudo-second-order kinetics. The adsorption well matched with Langmuir and Freundlich adsorption isotherms and found that adsorption capacity on alumina was more than silica. The thermodynamic studies proved that the adsorption was endothermic and chemisorptions (ΔH o > 40 kJ mol -1 ) on alumina and silica. Recovery of dye on alumina and silica were studied from 30 to 90 deg. C and observed that 52% of dye was recovered from alumina and only 3.5% from silica. The less recovery on silica proved the strong adsorption of dye on silica than alumina

Environmentally stable adsorbent of tetrahedral silica and non-tetrahedral alumina for removal and recovery of malachite green dye from aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Kannan, Chellapandian [Department of Chemistry, Periyar University, Salem 636011, Tamilnadu (India)], E-mail: chellapandiankannan@gmail.com; Sundaram, Thiravium [Department of Chemistry, Periyar University, Salem 636011, Tamilnadu (India); Palvannan, Thayumanavan [Department of Biochemistry, Periyar University, Salem 636011, Tamilnadu (India)

2008-08-30

The conventional adsorbents like activated carbon, agricultural wastes, molecular sieves, etc., used for dye adsorption are unstable in the environment for long time, and hence the adsorbed dyes again gets liberated and pollute the environment. To avoid this problem, environmentally stable adsorbent of silica and alumina should be employed for malachite green adsorption. The adsorbents were characterized by Fourier transformed infrared spectroscopy (FT-IR) to confirm the tetrahedral framework of silica and non-tetrahedral framework of alumina. The adsorption equilibrium of dye on alumina and silica were 4 and 5 h, respectively, this less adsorption time on alumina might be due to the less activation energy on alumina (63.46 kJ mol{sup -1}) than silica (69.93 kJ mol{sup -1}). Adsorption increased with increase of temperature on silica, in alumina, adsorption increased up to 60 deg. C, and further increase of temperature decreased the adsorption due to the structural change of non-tetrahedral alumina in water. The optimum pH for dye adsorption on alumina was 5 and silica was 6. The dye adsorptions on both adsorbents followed pseudo-second-order kinetics. The adsorption well matched with Langmuir and Freundlich adsorption isotherms and found that adsorption capacity on alumina was more than silica. The thermodynamic studies proved that the adsorption was endothermic and chemisorptions ({delta}H{sup o} > 40 kJ mol{sup -1}) on alumina and silica. Recovery of dye on alumina and silica were studied from 30 to 90 deg. C and observed that 52% of dye was recovered from alumina and only 3.5% from silica. The less recovery on silica proved the strong adsorption of dye on silica than alumina.

Highly efficient removal of Malachite green from water by a magnetic reduced graphene oxide/zeolitic imidazolate framework self-assembled nanocomposite

International Nuclear Information System (INIS)

Lin, Kun-Yi Andrew; Lee, Wei-Der

2016-01-01

Graphical abstract: - Highlights: • MRGO/ZIF nanocomposite was prepared via self-assembly and used for MG adsorption. • MRGO/ZIF can exhibit an ultra-high adsorption capacity for MG of ∼3000 mg g −1 . • Adsorption isotherm was properly fitted to the Langmuir–Freundlich isotherm model. • Effects of temperature, pH and co-existing compounds were investigated. • Recyclability of MRGO/ZIF for MG adsorption was highly efficient and stable. - Abstract: Compared to the relatively low adsorption capacities of conventional adsorbents for Malachite Green (MG) (i.e., ∼500 mg g −1 ), zeolitic imidazolate framework (ZIF) appears to be a promising adsorbent considering its significantly high adsorption capacity (i.e., >2000 mg g −1 ). Nevertheless, using such a nano-scale ZIF material for adsorption may lead to secondary contamination from the release of nanomaterials to the environment. Thus, ZIF has to be recovered conveniently to prevent the secondary contamination and facilitate the separation of adsorbent from water after adsorption. To this end, in this study ZIF nanocrystals were loaded on the sheet-like magnetic reduced graphene oxide (MRGO) to form a self-assembled MRGO/ZIF. The self-assembly of MRGO/ZIF was achieved possibly via the electrostatic attraction and the π–π stacking interaction between MRGO and ZIF. The resultant MRGO/ZIF exhibited an ultra-high adsorption capacity for MG (∼3000 mg g −1 ). The adsorption kinetics, isotherm, activation and thermodynamics were also determined. Other factors affecting the adsorption were examined including temperature, pH and co-existing ions/compound. To demonstrate that MRGO/ZIF can be recovered and reused, a multiple-cycle of MG adsorption using the regenerated MRGO/ZIF was revealed and the recyclability remained highly efficient and stable. The highly-effective, recoverable and re-usable features enable MRGO/ZIF a promising adsorbent to remove MG from water.

A novel "dual-potential" electrochemiluminescence aptasensor array using CdS quantum dots and luminol-gold nanoparticles as labels for simultaneous detection of malachite green and chloramphenicol.

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Feng, Xiaobin; Gan, Ning; Zhang, Huairong; Yan, Qing; Li, Tianhua; Cao, Yuting; Hu, Futao; Yu, Hongwei; Jiang, Qianli

2015-12-15

A novel type of "dual-potential" electrochemiluminescence (ECL) aptasensor array was fabricated on a homemade screen-printed carbon electrode (SPCE) for simultaneous detection of malachite green (MG) and chloramphenicol (CAP) in one single assay. The SPCE substrate consisted of a common Ag/AgCl reference electrode, carbon counter electrode and two carbon working electrodes (WE1 and WE2). In the system, CdS quantum dots (QDs) were modified on WE1 as cathode ECL emitters and luminol-gold nanoparticles (L-Au NPs) were modified on WE2 as anode ECL emitters. Then the MG aptamer complementary strand (MG cDNA) and CAP aptamer complementary strand (CAP cDNA) were attached on CdS QDs and L-Au NPs, respectively. The cDNA would hybridize with corresponding aptamer that was respectively tagged with cyanine dye (Cy5) (as quenchers of CdS QDs) and chlorogenic acid (CA) (as quenchers of l-Au NPs) using poly(ethylenimine) (PEI) as a bridging agent. PEI could lead to a large number of quenchers on the aptamer, which increased the quenching efficiency. Upon MG and CAP adding, the targets could induce strand release due to the highly affinity of analytes toward aptamers. Meanwhile, it could release the Cy5 and CA, which recovered cathode ECL of CdS QDs and anode ECL of L-Au NPs simultaneously. This "dual-potential" ECL strategy could be used to detect MG and CAP with the linear ranges of 0.1-100 nM and 0.2-150 nM, with detection limits of 0.03 nM and 0.07 nM (at 3sB), respectively. More importantly, this designed method was successfully applied to determine MG and CAP in real fish samples and held great potential in the food analysis. Copyright © 2015 Elsevier B.V. All rights reserved.

Removal of Triphenylmethane Dyes by Bacterial Consortium

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Jihane Cheriaa

2012-01-01

Full Text Available A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila-(CM-4 was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L and malachite green (50 mg/L dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes.

Cu(I)/Cu(II) mixed-valence surface complexes of S-[(2-hydroxyamino)-2-oxoethyl]-N,N-dibutyldithiocarbamate: Hydrophobic mechanism to malachite flotation.

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Liu, Sheng; Zhong, Hong; Liu, Guangyi; Xu, Zhenghe

2018-02-15

Hydroxamate and sulfhydryl surfactants are effective collectors for flotation of copper minerals. The combination application of hydroxamate and sulfhydryl collectors has been proved to be an effective approach for improving the flotation recovery of non-sulfide copper minerals. A surfactant owing both hydroxamate and dithiocarbamate groups might exhibit strong affinity to non-sulfide copper minerals through double sites adsorption, rendering an enhanced hydrophobization to non-sulfide copper minerals flotation. The flotation performance of S-[(2-hydroxyamino)-2-oxoethyl]- N,N-dibutyldithiocarbamate (HABTC) to malachite, calcite and quartz were first evaluated through systematic micro-flotation experiments. HABTC's hydrophobic mechanism to malachite was further investigated and analyzed by zeta potential, Fourier transform infrared spectroscopy (FTIR), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). The micro-flotation results demonstrated HABTC was an excellent collector for malachite flotation and exhibited favorable selectivity for flotation separation of malachite from quartz or calcite under pH 8.5-10.3. Zeta potential and FTIR implied that HABTC might bond with the surface copper atoms of malachite, with releasing the H + ions of its hydroxamate group into pulp. ToF-SIMS provided clear evidences that the Cu-hydroxamate and Cu-dithiocarbamate groups were formed on malachite surfaces after HABTC adsorption. XPS revealed that Cu(I)/Cu(II) mixed-valence surface complexes of HABTC anchored on malachite through formation of Cu(I)S and Cu(II)O bonds, accompanying with reduction of partial surface Cu(II) to Cu(I). The Cu(I)/Cu(II) mixed-valence double chelating character and "chair"-shape N,N-dibutyldithiocarbamate hydrophobic group, resulting in an enhanced affinity and hydrophobization of HABTC to malachite flotation. Copyright © 2017 Elsevier Inc. All rights reserved.

Malachite Green and Crystal Violet Decolorization by Ganoderma lucidum and Pleurotus ostreatus Supernatant and by rGlLCC1 and rPOXA 1B Concentrates: Molecular Docking Analysis.

Science.gov (United States)

Morales-Álvarez, Edwin D; Rivera-Hoyos, Claudia M; Poveda-Cuevas, Sergio A; Reyes-Guzmán, Edwin A; Pedroza-Rodríguez, Aura M; Reyes-Montaño, Edgar A; Poutou-Piñales, Raúl A

2018-03-01

Laccases catalyze the oxidation of various aromatic organic compounds concomitantly with molecular oxygen reduction to water. Triphenylmethane dyes are synthetic compounds widely used in diverse industries. Their removal from effluents is difficult, due to their high degree of structural complexity; hence, their high concentration in effluents cause a negative impact on the environment. In the present work, molecular docking was used to evaluate interactions between rGlLCC1 or rPOXA 1B enzymes with Crystal Violet (CV) or Malachite Green (MG) dyes. In addition, removal tests of the two dyes were performed. Van der Waals interactions were obtained for only the CV dye for both GlLCC1 and POXA 1B enzymes. Nevertheless, in the GlLCC1 model, two π-π interactions were observed. For the MG dye only, Van der Waals interactions were obtained. Moreover, amino acid composition interacting in each model with each dye was similar. It is important to highlight that by molecular docking, none of the estimated ligand configurations generated hydrogen bonds. Thus, explaining the difficulty to degrade CV and MG. Regarding CV, maximum decolorization percentage was 23.6 ± 1.0% using Ganoderma lucidum supernatant and 5.0 ± 0.5% with Pleurotus ostreatus supernatant. When using recombinant laccase enzyme concentrates, decolorization percentages were 9.9 ± 0.1 and 7.5 ± 1.0% for rGlLCC1 and rPOXA 1B, respectively. On the other hand, for the MG dye, maximum decolorization percentages were 52.1 ± 5.1 and 2.3 ± 0.2% using G. lucidum and P. ostreatus concentrates, respectively. Whereas with recombinant laccase enzymatic concentrates, values of 9.4 ± 0.8% were obtained, with rGlLCC1, and 2.1 ± 0.1% when using rPOXA 1B. These findings represent an important step in bioremediation processes improvement and efficiency of industry-generated products, using environmentally friendly alternatives.

A natural sorbent, Luffa cylindrica for the removal of a model basic dye

International Nuclear Information System (INIS)

Altinisik, Aylin; Guer, Emel; Seki, Yoldas

2010-01-01

In this work, application of Luffa cylindrica in malachite green (MG) removal from aqueous solution was studied in a batch system. The effect of contact time, pH and temperature on removal of malachite green was also investigated. By the time pH was increased from 3 to 5, the amount of sorbed malachite green also increased. Beyond the pH value of 5, the amount of sorbed malachite green remains constant. The fits of equilibrium sorption data to Langmuir, Freundlich and Dubinin-Radushkevich equations were investigated. Langmuir isotherm exhibited best fit with the experimental data. Monolayer sorption capacity increased with the increasing of temperature. Sorption kinetic was evaluated by pseudo-first-order, pseudo-second-order, Elovich rate equations and intraparticle diffusion models. It was inferred that sorption follows pseudo-second-order kinetic model. Thermodynamic parameters for sorption process were also found out. Spontaneous and endothermic nature of sorption was obtained due to negative value of free energy (ΔG o ) and positive value of enthalpy (ΔH o ) changes. FTIR analyses were also conducted to confirm the sorption of malachite green onto L. cylindrica.

[Spectral analysis of green pigments of painting and colored drawing in northern Chinese ancient architectures].

Science.gov (United States)

Wang, Li-Qin; Yan, Jing; Fan, Xiao-Lei; Ma, Tao

2010-02-01

It is important to identify pigments of painting and colored drawing in ancient architectures in order to restore and conserve them. The components of green pigments were detected with X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy-energy dispersive X-ray (SEM-EDX). Twenty-seven samples were collected from painting and colored drawing in northern Chinese ancient architectures in Beijing, Shanxi province and Gansu province. The experiment results showed that emerald green [CuCH3COO]2 x Cu(AsO2)2], a complex of copper aceto-arsenite pigment, had been used as the colored component in fifteen samples, whereas organic materials synthesized in the rest. However, in all samples there were no malachite and atacamite, green pigments commonly used in ancient time a long time ago. These two pigments have been found in Qin Shihuang's Terracotta Army and the wall paintings at Mogao Grettoes, Dunhuang, and some other famous wall paintings and color pottery figurines. However, emerald green was used many years later. It was reported that emerald green was synthesized by Germany in 1814 and had been widely used in China as watercolor on pith paper works and on scroll paintings since the 1850s. Because painting and colored drawing in ancient architectures stands outside, under sunlight and rain, it must be repaired and repainted in less than fifty years. Therefore, it is not surprising that emerald green was used in them. In recent years, artificial organic materials are increasingly used in painting and colored drawing in ancient architectures. From experiments it was also showed that in the same recolored painting and colored drawing, organic materials are usually in the later layers, but emerald green is in the earlier layers. This work supplies a lot of data for the purpose of selecting restoration materials and identifying painting and colored drawing in ancient architectures with a new method.

Comparison between dispersive solid-phase and dispersive liquid-liquid microextraction combined with spectrophotometric determination of malachite green in water samples based on ultrasound-assisted and preconcentration under multi-variable experimental design optimization.

Science.gov (United States)

Alipanahpour Dil, Ebrahim; Ghaedi, Mehrorang; Asfaram, Arash; Zare, Fahimeh; Mehrabi, Fatemeh; Sadeghfar, Fardin

2017-11-01

The ultrasound-assisted dispersive solid-phase microextraction (USA-DSPME) and the ultrasound-assisted dispersive liquid-liquid microextraction (USA-DLLME) developed for as an ultra preconcentration and/or technique for the determination of malachite green (MG) in water samples. Central composite design based on analysis of variance and desirability function guide finding best operational conditions and represent dependency of response to variables viz. volume of extraction, eluent and disperser solvent, pH, adsorbent mass and ultrasonication time has significant influence on methods efficiency. Optimum conditions was set for USA-DSPME as: 1mg CNTs/Zn:ZnO@Ni 2 P-NCs; 4min sonication time and 130μL eluent at pH 6.0. Meanwhile optimum point for USA-DLLME conditions were fixed at pH 6.0; 4min sonication time and 130, 650μL and 10mL of extraction solvent (CHCl 3 ), disperser solvent (ethanol) and sample volume, respectively. Under the above specified best operational conditions, the enrichment factors for the USA-DSPME and USA-DLLME were 88.89 and 147.30, respectively. The methods has linear response in the range of 20.0 to 4000.0ngmL -1 with the correlation coefficients (r) between 0.9980 to 0.9995, while its reasonable detection limits viz. 1.386 to 2.348ngmL -1 and good relative standard deviations varied from 1.1% to 2.8% (n=10) candidate this method for successful monitoring of analyte from various media. The relative recoveries of the MG dye from water samples at spiking level of 500ngmL -1 were in the range between 94.50% and 98.86%. The proposed methods has been successfully applied to the analysis of the MG dye in water samples, and a satisfactory result was obtained. Copyright © 2017. Published by Elsevier B.V.

Formation of gold nanorods and gold nanorod films for surface-enhanced Raman scattering spectroscopy

International Nuclear Information System (INIS)

Trotsyuk, L.L.; Kulakovich, O.S.; Shabunya-Klyachkovskaya, E.V.; Gaponenko, S.V.; Vashchenko, S.V.

2016-01-01

The formation of gold nanorods as well as thin films prepared via electrostatic deposition of gold nanorods has been investigated. The obtained gold nanorods films have been used as substrates for the surface-enhanced Raman scattering analysis of sulfur-free organic molecules mitoxantrone and malachite green as well as inorganic malachite microcrystals for the first time. The additional modification of films with L-cysteine allows one to significantly extend the use of gold nanorods for the surface-enhanced Raman scattering analysis. (authors)

On-line Raman spectroscopy of calcite and malachite during irradiation with swift heavy ions

International Nuclear Information System (INIS)

Dedera, Sebastian; Burchard, Michael; Glasmacher, Ulrich A.; Schöppner, Nicole; Trautmann, Christina; Severin, Daniel; Romanenko, Anton; Hubert, Christian

2015-01-01

A new on-line Raman System, which was installed at the M3-beamline at the UNILAC, GSI Helmholtzzentrum für Schwerionenforschung Darmstadt was used for first “in situ” spectroscopic measurements. Calcite and malachite samples were irradiated in steps between 1 × 10"9 and 1 × 10"1"2 ions/cm"2 with Au ions (calcite) and Xe ions (malachite) at an energy of 4.8 MeV/u. After irradiation, calcite revealed a new Raman band at 437 cm"−"1 and change of the full width at half maximum for the 1087 cm"−"1 Raman band. The Raman bands of malachite change significantly with increasing fluence. Up to a fluence of 7 × 10"1"0 ions/cm"2, all existing bands decrease in intensity. Between 8 × 10"1"0 and 1 × 10"1"1 ions/cm"2 a broad Cu_2O band between 110 and 220 cm"−"1 occurs, which superimposes the pre-existing Raman bands. Additionally, a new broad band between 1000 and 1750 cm"−"1 is formed, which is interpreted as a carbon coating. In contrast to the Cu_2O band, the carbon band vanished when further irradiating the sample. The installations as well as first in situ measurements at room temperature are presented.

Comparison of Adsorption of Phenol O-O and N-O Chelating Collectors at the Malachite/Water Interface in Flotation

Directory of Open Access Journals (Sweden)

Zhili Li

2017-02-01

Full Text Available To separate one base metal mineral from another by flotation, it is indispensable to identify chemical reagents that specifically interact with the surface metal sites of one mineral or a group of minerals. This work studies the interactions of chelating collectors which offer the best potential for collecting abilities and mineral specificity with a typical refractory oxide mineral (malachite. Zeta potential, adsorption and Fourier transform infrared (FTIR measurements are applied to differentiate the interactions of salicylaldoxime and salicyl hydroxamate on the malachite surface. Salicylaldoxime and salicyl hydroxamate are of molecular structures that resemble each other, but with different bond distances in the ligand atoms which result in their unusual adsorption behavior and collecting ability. Thus, the flotation of malachite behaves differently with the two chelating collectors. This study might provide useful clues for designing novel collectors in base metal oxide flotations.

Depletion layer characteristics and photovoltaic energy conversion in organic P-N heterojunctions

Energy Technology Data Exchange (ETDEWEB)

Chamberlain, G A

1983-11-01

The depletion layer characteristics of an organic p-n heterojunction were investigated by measuring the temperature variation of the capacitance, rectification and photovoltaic short-circuit current and open-circuit voltage. The cell consisted of indium-tin-oxide-coated glass/n-type malachite green/p-type merocyanine/Au exposed to chlorine vapour, in the absence of air, to effect the marked rectification and photovoltaic properties observed. Capacitance measurements indicate that a depletion layer of about 65 nm and a barrier height of about 0.8 eV are formed between the two dyes. The forward dark current is dominated by electron tunnelling from the malachite green to the merocyanine. Using an asymmetric trapping model, the reverse saturation current was explained as the thermally activated emission of electrons from filled traps at the Fermi energy of the merocyanine to empty traps in the malachite green over a barrier of 0.72+-0.1 eV. When the cell is working in the photovoltaic mode, the photocurrent is limited by the poor carrier photogeneration efficiency in the malachite green.

Quantum chemical and thermodynamic calculations of fulvic and humic copper complexes in reactions of malachite and azurite formation

International Nuclear Information System (INIS)

Fomin, Vitaliy N.; Gogol, Daniil B.; Rozhkovoy, Ivan E.; Ponomarev, Dmitriy L.

2017-01-01

This article provides a thermodynamic evaluation of the reactions of humic and fulvic acids in the process of malachite and azurite mineralogenesis. Semi-empirical methods AM/1, MNDO, PM3, PM5, PM6 and PM7 were used to compute the heat of formation, enthalpy and entropy for thermodynamic calculations of the reactions performed on the basis of Hess's law. It is shown that methods PM6 and PM7 in the MOPAC software package provide good compliance with experimental and calculated heats of formation for copper complexes and alkaline earth metal complexes with organic acids. It is found that the malachite and azurite formation processes involving humus complexing substances are thermodynamically possible. - Highlights: • Copper and alkali-earth metal complexes with humic and fulvic acids are considered. • Quantum chemical calculation of thermodynamics for the structures was performed. • Semi-empirical methods PM6 and PM7 provide best correlation for the properties. • Parameters of basic copper carbonate formation reactions were obtained by Hess's law. • Processes of malachite and azurite formation from humus complexes are possible.

Synthesis of malachite@clay nanocomposite for rapid scavenging of cationic and anionic dyes from synthetic wastewater.

Science.gov (United States)

Srivastava, Varsha; Sillanpää, Mika

2017-01-01

Synthesis of malachite@clay nanocomposite was successfully carried out for the removal of cationic (Methylene Blue, MB) and anionic dyes (Congo Red, CR) from synthetic wastewater. Nanocomposite was characterized by TEM, SEM, FT-IR, EDS analysis and zeta potential. TEM analysis indicated that the particle diameter of nanocomposite was in the range of 14 to 23nm. Various important parameters viz. contact time, concentration of dyes, nanocomposite dosage, temperature and solution pH were optimized to achieve maximum adsorption capacity. In the case of MB, removal decreased from 99.82% to 93.67% while for CR, removal decreased from 88.55% to 75.69% on increasing dye concentration from 100 to 450mg/L. pH study confirmed the higher removal of CR in acidic range while MB removal was higher in alkaline range. Kinetic study revealed the applicability of pseudo-second-order model for the adsorption of both dyes. Negative values of ΔG 0 for both systems suggested the feasibility of dye removal and support for spontaneous adsorption of CR and MB on nanocomposite. Nanocomposite showed 277.77 and 238.09mg/g Langmuir adsorption capacity for MB and CR respectively. Desorption of dyes from the dye loaded nanocomposite was easily carried out with acetone. The results indicate that the prepared malachite@clay nanocomposite is an efficient adsorbent with high adsorption capacity for the aforementioned dyes. Copyright © 2016. Published by Elsevier B.V.

Game Analysis and Countermeasures Discussion on Green Marketing

Institute of Scientific and Technical Information of China (English)

2011-01-01

On the basis of making certain assumption on the game situation of carrying out green marketing, this paper conducts game analysis on the green marketing choice among enterprises, the green marketing choice between enterprises and consumers, and the green marketing choice of consumers. Then this paper expounds the necessity of implementing green marketing as follows: the green marketing is the inevitable requirements of sustainable development of economy; the green marketing is the inevitable choice of green consumption mode; the green marketing is the inevitable results of legalization of environmental problems. The problems faced by the implementation of green marketing are analyzed as follows: first, the concept of green marketing has not yet been established; second, the sociality of green demand has not yet taken shape; third, production characteristic of green products has not yet formed. The countermeasures of implementing green marketing as follows: pay attention to the propaganda and education of modern marketing concept; regulate the competition in the market of green products; strengthen transparency of green market information; reinforce the legislation work of food safety.

Preparation, characterization and application of nanosized copper ferrite photocatalysts for dye degradation under UV irradiation

Energy Technology Data Exchange (ETDEWEB)

Zaharieva, Katerina, E-mail: zaharieva@ic.bas.bg [Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Block 11, 1113 Sofia (Bulgaria); Rives, Vicente, E-mail: vrives@usal.es [GIR-QUESCAT, Dpto. Química Inorgánica, Universidad de Salamanca, 37008 Salamanca (Spain); Tsvetkov, Martin, E-mail: mptsvetkov@gmail.com [Faculty of Chemistry and Pharmacy, St. Kliment Ohridski University of Sofia, 1 J. Bourchier Blvd., 1164 Sofia (Bulgaria); Cherkezova-Zheleva, Zara, E-mail: zzhel@ic.bas.bg [Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Block 11, 1113 Sofia (Bulgaria); Kunev, Boris, E-mail: bkunev@ic.bas.bg [Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Block 11, 1113 Sofia (Bulgaria); Trujillano, Raquel, E-mail: rakel@usal.es [GIR-QUESCAT, Dpto. Química Inorgánica, Universidad de Salamanca, 37008 Salamanca (Spain); Mitov, Ivan, E-mail: mitov@ic.bas.bg [Institute of Catalysis, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Block 11, 1113 Sofia (Bulgaria); Milanova, Maria, E-mail: nhmm@wmail.chem.uni-sofia.bg [Faculty of Chemistry and Pharmacy, St. Kliment Ohridski University of Sofia, 1 J. Bourchier Blvd., 1164 Sofia (Bulgaria)

2015-06-15

Nanosized copper ferrite-type materials (Cu{sub x}Fe{sub 3–x}O{sub 4}, 0 ≤ x ≤ 1) have been prepared by combination of co-precipitation and mechanochemical activation and/or thermal treatment. The crystalline structure and morphology of the obtained ferrite nanopowders have been characterized by different instrumental methods, such as Powder X-ray diffraction (PXRD), Mössbauer and FT-IR spectroscopies, specific surface area and porosity measurements, thermal analyses (Differential Thermal Analysis and Thermogravimetric Analysis) and Temperature-Programmed Reduction. The average crystallite size of copper ferrites ranged between 7.8 and 14.7 nm and show a superparamagnetic and collective magnetic excitations nature. The photocatalytic decolorization of Malachite green oxalate under different UV illumination intervals was examined using these copper ferrites as photocatalysts. The results indicate that the prepared nanostructured copper ferrites showed enhanced photocatalytic activity and amount adsorbed Malachite Green dye. The co-precipitated nanosized copper ferrite powder with a low content of copper metal ions in a magnetite host structure (Cu{sub 0.25}Fe{sub 2.75}O{sub 4}) showed an apparent pseudo-first-order rate constant 15.4 × 10{sup −3} min{sup −1} and an amount adsorbed Malachite Green as model organic dye pollutant per 1 g catalyst of 33.4 ppm/g after the dark period. The results confirm that the copper ferrites can be suitable for photocatalytic treatment of wastewaters containing organic dyes. The new aspect of presented investigations is to study the influence of different degree of incorporation of copper ions into the magnetite host structure and preparation methods on the photocatalytic properties of nanosized copper ferrite materials and obtaining of potential photocatalyst (Cu{sub 0.25}Fe{sub 2.75}O{sub 4}) with higher photocatalytic activity (15.4 × 10{sup −3} min{sup −1}) than that of the standard referent Degussa P25 (12 × 10

Preparation, characterization and application of nanosized copper ferrite photocatalysts for dye degradation under UV irradiation

International Nuclear Information System (INIS)

Zaharieva, Katerina; Rives, Vicente; Tsvetkov, Martin; Cherkezova-Zheleva, Zara; Kunev, Boris; Trujillano, Raquel; Mitov, Ivan; Milanova, Maria

2015-01-01

Nanosized copper ferrite-type materials (Cu x Fe 3–x O 4 , 0 ≤ x ≤ 1) have been prepared by combination of co-precipitation and mechanochemical activation and/or thermal treatment. The crystalline structure and morphology of the obtained ferrite nanopowders have been characterized by different instrumental methods, such as Powder X-ray diffraction (PXRD), Mössbauer and FT-IR spectroscopies, specific surface area and porosity measurements, thermal analyses (Differential Thermal Analysis and Thermogravimetric Analysis) and Temperature-Programmed Reduction. The average crystallite size of copper ferrites ranged between 7.8 and 14.7 nm and show a superparamagnetic and collective magnetic excitations nature. The photocatalytic decolorization of Malachite green oxalate under different UV illumination intervals was examined using these copper ferrites as photocatalysts. The results indicate that the prepared nanostructured copper ferrites showed enhanced photocatalytic activity and amount adsorbed Malachite Green dye. The co-precipitated nanosized copper ferrite powder with a low content of copper metal ions in a magnetite host structure (Cu 0.25 Fe 2.75 O 4 ) showed an apparent pseudo-first-order rate constant 15.4 × 10 −3 min −1 and an amount adsorbed Malachite Green as model organic dye pollutant per 1 g catalyst of 33.4 ppm/g after the dark period. The results confirm that the copper ferrites can be suitable for photocatalytic treatment of wastewaters containing organic dyes. The new aspect of presented investigations is to study the influence of different degree of incorporation of copper ions into the magnetite host structure and preparation methods on the photocatalytic properties of nanosized copper ferrite materials and obtaining of potential photocatalyst (Cu 0.25 Fe 2.75 O 4 ) with higher photocatalytic activity (15.4 × 10 −3 min −1 ) than that of the standard referent Degussa P25 (12 × 10 −3 min −1 ) for degradation of organic dye

Simultaneous spectrophotometric determination of crystal violet and malachite green in water samples using partial least squares regression and central composite design after preconcentration by dispersive solid-phase extraction.

Science.gov (United States)

Razi-Asrami, Mahboobeh; Ghasemi, Jahan B; Amiri, Nayereh; Sadeghi, Seyed Jamal

2017-04-01

In this paper, a simple, fast, and inexpensive method is introduced for the simultaneous spectrophotometric determination of crystal violet (CV) and malachite green (MG) contents in aquatic samples using partial least squares regression (PLS) as a multivariate calibration technique after preconcentration by graphene oxide (GO). The method was based on the sorption and desorption of analytes onto GO and direct determination by ultraviolet-visible spectrophotometric techniques. GO was synthesized according to Hummers method. To characterize the shape and structure of GO, FT-IR, SEM, and XRD were used. The effective factors on the extraction efficiency such as pH, extraction time, and the amount of adsorbent were optimized using central composite design. The optimum values of these factors were 6, 15 min, and 12 mg, respectively. The maximum capacity of GO for the adsorption of CV and MG was 63.17 and 77.02 mg g -1 , respectively. Preconcentration factors and extraction recoveries were obtained and were 19.6, 98% for CV and 20, 100% for MG, respectively. LOD and linear dynamic ranges for CV and MG were 0.009, 0.03-0.3, 0.015, and 0.05-0.5 (μg mL -1 ), respectively. The intra-day and inter-day relative standard deviations were 1.99 and 0.58 for CV and 1.69 and 3.13 for MG at the concentration level of 50 ng mL -1 , respectively. Finally, the proposed DSPE/PLS method was successfully applied for the simultaneous determination of the trace amount of CV and MG in the real water samples.

GREEN PACKAGING, GREEN PRODUCT, GREEN ADVERTISING, PERSEPSI, DAN MINAT BELI KONSUMEN

Directory of Open Access Journals (Sweden)

Imam Santoso

2016-12-01

Full Text Available Environmental problems become one of the strategic issues in achieving global competitiveness. One of the issues is products that are made from environmental friendly materials or known as green product. Furthermore, in green products marketing, the company also uses green packaging and green advertising concept. This study aimed to analyze the effect of green packaging, green products, and green advertising on consumer perception and purchasing intention. The study was conducted in Ketawanggede Village, Lowokwaru Sub-district, Malang City. The sampling method used nonprobability accidential sampling techniques. The numbers of respondents were 113 consumers in study site. Data were collected by interview using questionnaires. The method of analysis used Generalized Structured Component Analysis (GSCA. The analysis showed that the green packaging, green products, and green advertising had positive significant influence on consumer perceptions. Meanwhile, green product and consumer perception had positive significant influence on purchasing interest, but the green packaging and green advertising has not found sufficient evidence in influencing purchasing intention.

Isotherms and kinetic study of ultrasound-assisted adsorption of malachite green and Pb2+ ions from aqueous samples by copper sulfide nanorods loaded on activated carbon: Experimental design optimization.

Science.gov (United States)

Sharifpour, Ebrahim; Khafri, Hossein Zare; Ghaedi, Mehrorang; Asfaram, Arash; Jannesar, Ramin

2018-01-01

Copper sulfide nanorods loaded on activated carbon (CuS-NRs-AC) was synthesized and used for simultaneous ultrasound-assisted adsorption of malachite green (MG) and Pb 2+ ions from aqueous solution. Following characterization of CuS-NRs-AC were investigated by SEM, EDX, TEM and XRD, the effects of pH (2.0-10), amount of adsorbent (0.003-0.011g), MG concentration (5-25mgL -1 ), Pb 2+ concentration (3-15mgL -1 ) and sonication time (1.5-7.5min) and their interactions on responses were investigated by central composite design (CCD) and response surface methodology. According to desirability function on the Design Expert optimum removal (99.4%±1.0 for MG and 68.3±1.8 for Pb 2+ ions) was obtained at pH 6.0, 0.009g CuS-NRs-AC, 6.0min mixing by sonication and 15 and 6mgL -1 for MG and Pb 2+ ions, respectively. High determination coefficient (R 2 >0.995), Pred-R 2 -value (>0.920) and Adju-R 2 -value (>0.985) all are good indication of best agreement between the experimental and design modelling. The adsorption kinetics follows the pseudo-second order model and adsorption isotherm follows the Langmuir model with maximum adsorption capacity of 145.98 and 47.892mgg -1 for MG and Pb 2+ ions, respectively. This adsorbent over short contact time is good choice for simultaneous removal of large content of both MG and Pb 2+ ions from wastewater sample. Copyright © 2017 Elsevier B.V. All rights reserved.

PLACE-BASED GREEN BUILDING: INTEGRATING LOCAL ENVIRONMENTAL AND PLANNING ANALYSIS INTO GREEN BUILDING GUIDELINES

Science.gov (United States)

This project will develop a model for place-based green building guidelines based on an analysis of local environmental, social, and land use conditions. The ultimate goal of this project is to develop a methodology and model for placing green buildings within their local cont...

Probabilistic economic analysis of green roof benefits for policy design

International Nuclear Information System (INIS)

Clark, C.; Adriaens, P.; Talbot, B.

2006-01-01

The installation costs of green roofs continue to deter widespread use of green roof technology. Analyses of the boundary conditions for the cost differential between a green roof and a conventional roof are usually compared to environmental benefits such as storm water reduction and building energy savings. However, evidence is emerging that green roofs may play a role in urban air quality improvement. This paper discussed a methodology for developing probabilistic ranges of benefits and cost analyses. A probabilistic analysis was conducted to prepare a generalized cost-benefit analysis for application to a range of green roof projects. Environmental benefits of roof greening were quantified on a per unit surface area to assess environmental impact at the building scale. Parameters included conventional and green roof installation costs; storm water fees and fee reductions for green roofs; energy costs due to heat flux and the resultant savings through the installation of a green roof and the additional economic valuation of the public health benefits due to air pollution mitigation. Results were then integrated into an economic model to determine the length of time required for a return on investment in a green roof, assuming that a traditional roof would require replacement after 20 years. A net present value analysis was performed for an average-sized university roof. Results of the study showed that a valuation of environmental benefits can reduce the time required for a return on investment in a moderately priced green roof. While reduced installation costs reduced the time required for a return on investment, optimizing the green roof system for maximum environmental benefit had a greater potential to provide a higher return. It was concluded that the benefit of improved air quality should not be ignored by green roof policy-makers as a valuation tool. 10 refs., 3 tabs., 1 fig

Green Purchasing Behavior Analysis of Government Policy About Paid Plastic Bags

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Muhammad Khoiruman

2017-06-01

Full Text Available This research will be conducted to know: 1 The influence of green perceived value to consumer green trust to use plastic bag after the policy of using plastic bag paid at modern retail store in Surakarta. 2 The influence of green perceived risk to consumer green trust to use plastic bag after the policy of using plastic bag paid at modern retail store in Surakarta. 3 The effect of green trust on green purchase behavior of consumers to use plastic bags after the policy of using plastic bag paid at modern retail store in Surakarta. The study was conducted in modern retail stores (Alfamart, Indomart and Superindo in Surakarta using 200 respondents who shop at the modern retail store. A model that can be used to measure green purchasing behavior in the use of paid plastic bags using four interrelated variables: green perceived value, green perceived risk, green trust and green purchasing. Data analysis using Structural Equation Model (SEM. The result of analysis and discussion showed that green perceived value have positive and significant effect to green trust, green trust has positive effect on green purchasing, but green perceived risk has no significant effect to green trust.

Determination of tantalum in standard steels by INAA and absorption spectrophotometry

Energy Technology Data Exchange (ETDEWEB)

Obrusnik, I; Posta, S [Ustav Jaderneho Vyzkumu, Rez (Czechoslovakia)

1978-02-14

Two analytical methods, instrumental neutron activation analysis (INAA) and absorption spectrophotometry with malachite green, have been used for the determination of tantalum in standard steels produced by the Research Institute of CKD Prague - steels No. 167 and No. 169 with expected concentrations of Ta 0.01% and 0.03%, respectively. INAA method consisted of irradiation of steel samples (chips) in a nuclear reactor and Ge(Li) ..gamma..-ray spectrometry after a cooling period of one month. A spectrophotometric determination is based on the extraction of ionic associate of TaF/sub 6//sup -/ with malachite green into Oenzene from a solution of diluted sulphuric acid and hydrofluoric acid. The results obtained by the two methods are in a good agreement. However, INAA method is more sensitive and precise then spectrophotometry for the determination of tantalum in steels in the above-mentioned concentration ranges.

Determination of tantalum in standard steels by INAA and absorption spectrophotometry

International Nuclear Information System (INIS)

Obrusnik, I.; Posta, S.

1978-01-01

Two analytical methods, instrumental neutron activation analysis (INAA) and absorption spectrophotometry with malachite green, have been used for the determination of tantalum in standard steels produced by the Research Institute of CKD Prague - steels No. 167 and No. 169 with expected concentrations of Ta 0.01% and 0.03%, respectively. INAA method consisted of irradiation of steel samples (chips) in a nuclear reactor and Ge(Li) γ-ray spectrometry after a cooling period of one month. A spectrophotometric determination is based on the extraction of ionic associate of TaF 6 - with malachite green into Oenzene from a solution of diluted sulphuric acid and hydrofluoric acid. The results obtained by the two methods are in a good agreement. However, INAA method is more sensitive and precise then spectrophotometry for the determination of tantalum in steels in the above-mentioned concentration ranges. (author)

Active Greens : An Analysis of the Determinants of Green Party Members' Activism in Environmental Movements

NARCIS (Netherlands)

Botetzagias, Iosif; van Schuur, Wijbrandt

This article investigates green party members' activism in the environmental movement and tests how a number of predictors, theoretically suggested in the past yet rarely empirically tested, can account for it. The authors' analysis is based on an extensive data set of members of 15 green parties in

Identification of green pigments from fragments of Roman mural paintings of three Roman sites from north of Germania Superior

Science.gov (United States)

Debastiani, Rafaela; Simon, Rolf; Goettlicher, Joerg; Heissler, Stefan; Steininger, Ralph; Batchelor, David; Fiederle, Michael; Baumbach, Tilo

2016-10-01

Roman mural green pigment painting fragments from three Roman sites in the north of the Roman province Germania Superior: Koblenz Stadtwald Remstecken (KOSR), Weißenthurm " Am guten Mann" (WEIS) and Mendig Lungenkärchen (MELU), dating from second and third centuries AD were analyzed. The experiments were performed nondestructively using synchrotron-based scanning macro-X-ray fluorescence (SR-MA-XRF), synchrotron-based scanning micro-X-ray fluorescence (SR-μ-XRF), synchrotron-based X-ray diffraction (SR-XRD) and Raman spectroscopy. Correlation between SR-MA-XRF, SR-μ-XRF elemental map distributions and optical images of scanned areas was mainly found for the elements Ca, Fe and K. With XRF, Fe and K were identified correlated with green pigment, but in samples from two sites, Mendig Lungenkärchen and Weißenthurm " Am guten Mann", also Cu was detected in minor concentration. The results of SR-XRD and Raman spectroscopy were limited to one sample from Weißenthurm " Am guten Mann". In this sample, green earth and calcium carbonate were identified by SR-XRD and, additionally, malachite by Raman spectroscopy.

Monitoring urban greenness dynamics using multiple endmember spectral mixture analysis.

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Muye Gan

Full Text Available Urban greenness is increasingly recognized as an essential constituent of the urban environment and can provide a range of services and enhance residents' quality of life. Understanding the pattern of urban greenness and exploring its spatiotemporal dynamics would contribute valuable information for urban planning. In this paper, we investigated the pattern of urban greenness in Hangzhou, China, over the past two decades using time series Landsat-5 TM data obtained in 1990, 2002, and 2010. Multiple endmember spectral mixture analysis was used to derive vegetation cover fractions at the subpixel level. An RGB-vegetation fraction model, change intensity analysis and the concentric technique were integrated to reveal the detailed, spatial characteristics and the overall pattern of change in the vegetation cover fraction. Our results demonstrated the ability of multiple endmember spectral mixture analysis to accurately model the vegetation cover fraction in pixels despite the complex spectral confusion of different land cover types. The integration of multiple techniques revealed various changing patterns in urban greenness in this region. The overall vegetation cover has exhibited a drastic decrease over the past two decades, while no significant change occurred in the scenic spots that were studied. Meanwhile, a remarkable recovery of greenness was observed in the existing urban area. The increasing coverage of small green patches has played a vital role in the recovery of urban greenness. These changing patterns were more obvious during the period from 2002 to 2010 than from 1990 to 2002, and they revealed the combined effects of rapid urbanization and greening policies. This work demonstrates the usefulness of time series of vegetation cover fractions for conducting accurate and in-depth studies of the long-term trajectories of urban greenness to obtain meaningful information for sustainable urban development.

Assessing green waste route by using Network Analysis

Science.gov (United States)

Hasmantika, I. H.; Maryono, M.

2018-02-01

Green waste, such as waste from park need treat proper. One of the main problems of green waste management is how to design optimum collection. This research aims to determine the optimum green waste collection by determining optimum route among park. The route optimum was assessed by using network analysis method. And the region five of Semarang city’s park within 20 parks in chose as case study. To enhancing recycle of green waste, three scenarios of treatment are proposed. Scenario 1 used one integrated treatment facility as terminal for enhancing recycle of green waste, Scenario 2 used two sites and scenario 3 used three sites. According to the assessment, the length of route of scenario 1 is 36.126 km and the time for collection estimated is 46 minutes. In scenario 2, the length of route is 36.471 km with a travel time is 47 minutes. The length of scenario three is 46.934 km and the time of collection is 60 minutes.

Development of an LC-MS based enzyme activity assay for MurC: application to evaluation of inhibitors and kinetic analysis.

Science.gov (United States)

Deng, Gejing; Gu, Rong-Fang; Marmor, Stephen; Fisher, Stewart L; Jahic, Haris; Sanyal, Gautam

2004-06-29

An enzyme activity assay, based on mass spectrometric (MS) detection of specific reaction product following HPLC separation, has been developed to evaluate pharmaceutical hits identified from primary high throughput screening (HTS) against target enzyme Escherichia coli UDP-N-acetyl-muramyl-L-alanine ligase (MurC), an essential enzyme in the bacterial peptidoglycan biosynthetic pathway, and to study the kinetics of the enzyme. A comparative analysis of this new liquid chromatographic-MS (LC-MS) based assay with a conventional spectrophotometric Malachite Green (MG) assay, which detects phosphate produced in the reaction, was performed. The results demonstrated that the LC-MS assay, which determines specific ligase activity of MurC, offers several advantages including a lower background (0.2% versus 26%), higher sensitivity (> or = 10 fold), lower limit of quantitation (LOQ) (0.02 microM versus 1 microM) and wider linear dynamic range (> or = 4 fold) than the MG assay. Good precision for the LC-MS assay was demonstrated by the low intraday and interday coefficient of variation (CV) values (3 and 6%, respectively). The LC-MS assay, free of the artifacts often seen in the Malachite Green assay, offers a valuable secondary assay for hit evaluation in which the false positives from the primary high throughput screening can be eliminated. In addition, the applicability of this assay to the study of enzyme kinetics has also been demonstrated. Copyright 2004 Elsevier B.V.

Green Infrastructure Siting and Cost Effectiveness Analysis

Data.gov (United States)

Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Parcel scale green infrastructure siting and cost effectiveness analysis. You can find more details at the project's website.

Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

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Paul S Bergman

Full Text Available Environmental DNA (eDNA is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods.

Role of P27 -P55 operon from Mycobacterium tuberculosis in the resistance to toxic compounds

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Cataldi Angel A

2011-07-01

Full Text Available Abstract Background The P27-P55 (lprG-Rv1410c operon is crucial for the survival of Mycobacterium tuberculosis, the causative agent of human tuberculosis, during infection in mice. P55 encodes an efflux pump that has been shown to provide Mycobacterium smegmatis and Mycobacterium bovis BCG with resistance to several drugs, while P27 encodes a mannosylated glycoprotein previously described as an antigen that modulates the immune response against mycobacteria. The objective of this study was to determine the individual contribution of the proteins encoded in the P27-P55 operon to the resistance to toxic compounds and to the cell wall integrity of M. tuberculosis. Method In order to test the susceptibility of a mutant of M. tuberculosis H37Rv in the P27-P55 operon to malachite green, sodium dodecyl sulfate, ethidium bromide, and first-line antituberculosis drugs, this strain together with the wild type strain and a set of complemented strains were cultivated in the presence and in the absence of these drugs. In addition, the malachite green decolorization rate of each strain was obtained from decolorization curves of malachite green in PBS containing bacterial suspensions. Results The mutant strain decolorized malachite green faster than the wild type strain and was hypersensitive to both malachite green and ethidium bromide, and more susceptible to the first-line antituberculosis drugs: isoniazid and ethambutol. The pump inhibitor reserpine reversed M. tuberculosis resistance to ethidium bromide. These results suggest that P27-P55 functions through an efflux-pump like mechanism. In addition, deletion of the P27-P55 operon made M. tuberculosis susceptible to sodium dodecyl sulfate, suggesting that the lack of both proteins causes alterations in the cell wall permeability of the bacterium. Importantly, both P27 and P55 are required to restore the wild type phenotypes in the mutant. Conclusions The results clearly indicate that P27 and P55 are

SWOT Analysis of Urban Greening Maintenance and Management in the Central Pearl River Delta

Institute of Scientific and Technical Information of China (English)

Yanning; ZHENG; Fang; JIANG

2013-01-01

We take Shunde District,Foshan City in Guangdong Province for example,to carry out SWOT analysis of urban greening maintenance and management.The strengths of greening management and maintenance in Shunde District are as follows:(i)The greening area and quality are continuously improved in the downtown of Shunde District;(ii)The management and maintenance work is carried out well;(iii)The management and maintenance level tends to be increasingly perfected.The weaknesses of greening management and maintenance are as follows:(i)The fees for greening management and maintenance are very low;(ii)There is corner as yet untouched in the junction of some town streets;(iii)The greening management and maintenance technicians are unprofessional;(iv)The greening management is not in place;(v)There is management vacancy phenomenon in the management and maintenance of regional green space;(vi)The design and construction phase is flawed.Finally,based on the analysis of strengths and weaknesses of greening,we put forth the recommendations for the development of management and maintenance in urban green space.

One electron reduction of triphenyl methane dyes by hydrated electrons

Energy Technology Data Exchange (ETDEWEB)

Bhasikuttan, A C; Shastri, L V; Sapre, A V; Rama Rao, K V.S. [Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.

1994-12-31

Electron reaction rates for the triphenylmethane (TPM) dyes have been evaluated. Spectral characteristics of the resulting dye radicals have been determined. Evolution of the transient spectra shows intramolecular rearrangement in the radical from brilliant green and malachite green. (author). 3 refs., 1 fig., 1 tab.

One electron reduction of triphenyl methane dyes by hydrated electrons

International Nuclear Information System (INIS)

Bhasikuttan, A.C.; Shastri, L.V.; Sapre, A.V.; Rama Rao, K.V.S.

1994-01-01

Electron reaction rates for the triphenylmethane (TPM) dyes have been evaluated. Spectral characteristics of the resulting dye radicals have been determined. Evolution of the transient spectra shows intramolecular rearrangement in the radical from brilliant green and malachite green. (author). 3 refs., 1 fig., 1 tab

Customers’ Intention to Use Green Products: the Impact of Green Brand Dimensions and Green Perceived Value

Directory of Open Access Journals (Sweden)

Doszhanov Aibek

2015-01-01

Full Text Available This study aimed to identify the relationships between green brand dimension (green brand awareness, green brand image, and green brand trust, green perceived value and customer’s intention to use green products. Data was collected through structured survey questionnaire from 384 customers of three hypermarkets in Kuala-Lumpur. Data was analyzed based on multiple regression analysis. The results indicate that there are significant relationships between green brand awareness, green brand trust, green perceived value, and customer’s intention to use green products. However, green brand image was not found to have significant relationship with customer’s intention to use green products. The discussion presented suggestions for marketers and researchers interested in green branding.

Is Green Regulation Effective or a Failure: Comparative Analysis between Bangladesh Bank (BB Green Guidelines and Global Reporting Initiative Guidelines

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Md. Abdul Kaium Masud

2018-04-01

Full Text Available Green reporting and green regulation have been commonly used in the sustainability movement. This study evaluates Bangladesh Bank’s (BB’s green regulation by considering the global reporting initiative (GRI of environmental regulation along with self-determined content to justify BB’s institutional effort in the banking sector. The analytical study has considered secondary data of all listed banks on the Dhaka Stock Exchange between 2013 to 2016. A multi-theoretical framework has been adopted in which the research is comprised of institutional, stakeholder, and legitimacy theories. Considering the analytical research, we have drawn-up a green reporting score and undertaken SWOT analysis. The results of the study have identified the narrow coverage of BB’s regulation and strategic limitations. Moreover, the findings of the study show that banking companies disclosed more green information in line with BB’s regulation. Furthermore, our analysis has found the lack of transparency of green reporting in terms of absent global reporting as well as external verification. Additionally, we have documented that BB’s regulation falls into a legitimacy threat owing to political, corporate, and social responsibility. Therefore, we concluded that for BB to overcome all possible weaknesses and threats, it should consider all possible opportunities for a holistic international reporting framework while taking into account a transparent financial sector.

Multivariate qualitative analysis of banned additives in food safety using surface enhanced Raman scattering spectroscopy

Science.gov (United States)

He, Shixuan; Xie, Wanyi; Zhang, Wei; Zhang, Liqun; Wang, Yunxia; Liu, Xiaoling; Liu, Yulong; Du, Chunlei

2015-02-01

A novel strategy which combines iteratively cubic spline fitting baseline correction method with discriminant partial least squares qualitative analysis is employed to analyze the surface enhanced Raman scattering (SERS) spectroscopy of banned food additives, such as Sudan I dye and Rhodamine B in food, Malachite green residues in aquaculture fish. Multivariate qualitative analysis methods, using the combination of spectra preprocessing iteratively cubic spline fitting (ICSF) baseline correction with principal component analysis (PCA) and discriminant partial least squares (DPLS) classification respectively, are applied to investigate the effectiveness of SERS spectroscopy for predicting the class assignments of unknown banned food additives. PCA cannot be used to predict the class assignments of unknown samples. However, the DPLS classification can discriminate the class assignment of unknown banned additives using the information of differences in relative intensities. The results demonstrate that SERS spectroscopy combined with ICSF baseline correction method and exploratory analysis methodology DPLS classification can be potentially used for distinguishing the banned food additives in field of food safety.

Analysis and prospects of the green certificates market

International Nuclear Information System (INIS)

Allegri, S.; Zorzoli, G.B.

2000-01-01

This paper presents an analysis on the possible development of electric energy production from renewable sources in Italy, in relation to financial incentives provided by Bersani Decree. The value of green certificates has been analysed and determined [it

Metaphysical green

DEFF Research Database (Denmark)

Earon, Ofri

2011-01-01

example is a tiny Danish summer house from 1918 . The second example is ‘House before House’ , in Tokyo. The third example is a prefabricated house ‘CHU’ . The analysis evaluates the characteristics of diverse tones of green – from green image to green sensation. The analysis is based on the original...... of Sensation of Green is created by a physical interaction between the language of space and the language of nature” The notion of Sensation of Green was developed through a previous study ‘Learning from the Summer House’ investigating the unique architectural characteristics of the Danish summer houses...... the Sensation of Green? Three existing examples are agents to this discussion. The first example is a Danish summer house. The other two are international urban examples. While the summer house articulates the original meaning of Sensation of Green, the urban examples illustrate its urban context. The first...

Quantitative analysis on the urban flood mitigation effect by the extensive green roof system.

Science.gov (United States)

Lee, J Y; Moon, H J; Kim, T I; Kim, H W; Han, M Y

2013-10-01

Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. © 2013 Elsevier Ltd. All rights reserved.

Green roof valuation: a probabilistic economic analysis of environmental benefits.

Science.gov (United States)

Clark, Corrie; Adriaens, Peter; Talbot, F Brian

2008-03-15

Green (vegetated) roofs have gained global acceptance as a technologythat has the potential to help mitigate the multifaceted, complex environmental problems of urban centers. While policies that encourage green roofs exist atthe local and regional level, installation costs remain at a premium and deter investment in this technology. The objective of this paper is to quantitatively integrate the range of stormwater, energy, and air pollution benefits of green roofs into an economic model that captures the building-specific scale. Currently, green roofs are primarily valued on increased roof longevity, reduced stormwater runoff, and decreased building energy consumption. Proper valuation of these benefits can reduce the present value of a green roof if investors look beyond the upfront capital costs. Net present value (NPV) analysis comparing a conventional roof system to an extensive green roof system demonstrates that at the end of the green roof lifetime the NPV for the green roof is between 20.3 and 25.2% less than the NPV for the conventional roof over 40 years. The additional upfront investment is recovered at the time when a conventional roof would be replaced. Increasing evidence suggests that green roofs may play a significant role in urban air quality improvement For example, uptake of N0x is estimated to range from $1683 to $6383 per metric ton of NOx reduction. These benefits were included in this study, and results translate to an annual benefit of $895-3392 for a 2000 square meter vegetated roof. Improved air quality leads to a mean NPV for the green roof that is 24.5-40.2% less than the mean conventional roof NPV. Through innovative policies, the inclusion of air pollution mitigation and the reduction of municipal stormwater infrastructure costs in economic valuation of environmental benefits of green roofs can reduce the cost gap that currently hinders U.S. investment in green roof technology.

A new alternative adsorbent for the removal of cationic dyes from aqueous solution

Directory of Open Access Journals (Sweden)

T. Santhi

2016-09-01

Full Text Available Adsorption of Malachite green (MG and Methylene blue (MB from aqueous solutions on low cost adsorbent prepared from Annona squmosa seed (CAS is studied experimentally. Results obtained indicate that the removal efficiency of Malachite green and Methylene blue at 27 ± 2 °C exceeds 75.66% and 24.33% respectively, and that the adsorption process is highly pH-dependent. Results showed that the optimum pH for dye removal is 6.0. The amount of dye adsorbed from aqueous solution increases with the increase of the initial dye concentration. Smaller adsorbent particle adds to increase the percentage removal of Malachite green and Methylene blue. The equilibrium data fitted well to the Langmuir model (R2 > 0.97 and the adsorption kinetic followed the pseudo-second-order equation (R2 > 0.99. The maximum adsorption capacities of MG, MB on CAS are 25.91 mg g−1 and 08.52 mg g−1 respectively. These results suggest that A. squmosa seed is a potential low-cost adsorbent for the dye removal from industrial wastewater. The adsorption capacity of CAS on MG is greater than MB.

Aegle marmelos Mediated Green Synthesis of Different Nanostructured Metal Hexacyanoferrates: Activity against Photodegradation of Harmful Organic Dyes

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Vidhisha Jassal

2016-01-01

Full Text Available Prussian blue analogue potassium metal hexacyanoferrate (KMHCF nanoparticles Fe4[Fe(CN6]3 (FeHCF, K2Cu3[Fe(CN6]2 (KCuHCF, K2Ni[Fe(CN6]·3H2O (KNiHCF, and K2Co[Fe(CN6] (KCoHCF have been synthesized using plant based biosurfactant Aegle marmelos (Bael and water as a green solvent. It must be emphasized here that no harmful reagent or solvent was used throughout the study. Plant extracts are easily biodegradable and therefore do not cause any harm to the environment. Hence, the proposed method of synthesis of various KMHCF nanoparticles followed a green path. The synthesized nanoparticles were characterized by powder X-ray diffraction (PXRD, Field-Emission Scanning Electron Microscopy (FE-SEM, Transmission Electron Microscopy (TEM, and Fourier Transform Infrared Spectroscopy (FT-IR. MHCF nanoparticles were used for the photocatalytic degradation of toxic dyes like Malachite Green (MG, Eriochrome Black T (EBT, Methyl Orange (MO, and Methylene Blue (MB. Under optimized reaction conditions, maximum photocatalytic degradation was achieved in case of KCuHCF nanoparticles mediated degradation process (MG: 96.06%, EBT: 83.03%, MB: 94.72%, and MO: 63.71% followed by KNiHCF (MG: 95%, EBT: 80.32%, MB: 91.35%, and MO: 59.42%, KCoHCF (MG: 91.45%, EBT: 78.84%, MB: 89.28%, and MO: 58.20%.

Influence of donor-donor transport on excitation energy transfer

Energy Technology Data Exchange (ETDEWEB)

Pandey, K K; Joshi, H C; Pant, T C [Kumaun University, Nainital (India). Department of Physics

1989-01-01

Energy migration and transfer from acriflavine to rhodamine B and malachite green in poly (methylmethacrylate) have been investigated using the decay function analysis. It is found that the influence of energy migration in energy transfer can be described quite convincingly by making use of the theories of Loring, Andersen and Fayer (LAF) and Huber. At high acceptor concentration direct donor-acceptor transfer occurs through Forster mechanism. (author). 17 refs., 5 figs.

GREEN MARKETING AND REPRESENTATION OF THE OTHER (An Analysis of Green Image Ad Represented by Teh Kotak Ad, ‘Persembahan dari Alam’ Version

Directory of Open Access Journals (Sweden)

Tangguh Okta Wibowo

2017-12-01

Full Text Available This paper presents a theoretical link among green marketing of Teh Kotak ad, “Persembahan dari Alam” version. This is an ad telling as if the product of Teh Kotak is truly from nature. In addition, this research explored the portrayal of how this ad contains metaphorical element to juxtapose nature and technology as the same level. In the analysis, this study attempts to use Green marketing theory as a tool for analysis to explore what is the message behind the ad. Moreover, exploring the representation of the portion of the position of gender where the ad uses a woman as the main actor picking tea leaf, as if this ad looks natural. The result of the study revealed that Green marketing showed it competences to cover with political agenda. It is reflected in green image which told that The Kotak is a gift from nature. Overall, this study concludes that green image of this ad relays the hidden meaning, where the main aim is inviting people to buy its product as political agendas. Keywords: Green marketing; gift; Nature; Teh Kotak

Text mining factor analysis (TFA) in green tea patent data

Science.gov (United States)

Rahmawati, Sela; Suprijadi, Jadi; Zulhanif

2017-03-01

Factor analysis has become one of the most widely used multivariate statistical procedures in applied research endeavors across a multitude of domains. There are two main types of analyses based on factor analysis: Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Both EFA and CFA aim to observed relationships among a group of indicators with a latent variable, but they differ fundamentally, a priori and restrictions made to the factor model. This method will be applied to patent data technology sector green tea to determine the development technology of green tea in the world. Patent analysis is useful in identifying the future technological trends in a specific field of technology. Database patent are obtained from agency European Patent Organization (EPO). In this paper, CFA model will be applied to the nominal data, which obtain from the presence absence matrix. While doing processing, analysis CFA for nominal data analysis was based on Tetrachoric matrix. Meanwhile, EFA model will be applied on a title from sector technology dominant. Title will be pre-processing first using text mining analysis.

The Study of Critical Eco-Linguistic in Green Discourse: Prospective Eco-Linguistic Analysis

Directory of Open Access Journals (Sweden)

Tommi Yuniawan

2017-10-01

Full Text Available Eco-linguistic studies are influenced by one of the other interdisciplinary sciences, namely critical discourse analysis. The combination of these two sciences is called critical eco-linguistic studies. Critical eco-linguistic examines the discourse about the environment and various forms of discourse and their ideology which concerns people and the environment. The environmental discourse with all its manifestations (oral text, written text is called green discourse. To that end, critical eco-linguistic dictates the linguistic aspects contained in the green discourse. Utilization of lingual units in green discourse will affect the sense and logic of people involved in the discourse, ie the writers and readers or the speakers and the speakers. What is recorded in their cognition, will affect their attitudes and actions to the environment. If green discourse is constructive, then their attitude and actions to the environment are constructive. Conversely, if green discourse is more destructive and exploitative, then their attitudes and actions towards the environment will also be affected towards destruction and exploitation. For this reason, critical eco-linguistic studies in green discourse deserve to be given space as a form of prospective eco-linguistic analysis.

Quantitative analysis on the urban flood mitigation effect by the extensive green roof system

International Nuclear Information System (INIS)

Lee, J.Y.; Moon, H.J.; Kim, T.I.; Kim, H.W.; Han, M.Y.

2013-01-01

Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. -- Highlights: •Urban extensive green roof systems have a synergetic effect in mitigating urban runoff. •These systems are improve runoff mitigation and decentralized urban water management. •These systems have a high water-retaining capacity response to rainfall of less than 20 mm/h. •The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52. -- Extensive green-roofs are an effective storm water best-management practice and the proposed parameters can be applied to mitigate urban runoff

Low temperature measurements of the heat capacity and thermodynamic functions of pseudo-malachite Cu5(PO4)2(OH)4

International Nuclear Information System (INIS)

Bissengaliyeva, M.R.; Gogol, D.B.; Bekturganov, N.S.

2012-01-01

The investigation of the heat capacity of a natural specimen of copper phosphate—pseudo-malachite Cu 5 (PO 4 ) 2 (OH) 4 in the temperature range between 4.2 K and 320 K has been carried out by the method of low-temperature adiabatic calorimetry. Tabulated values of the heat capacity and thermodynamic functions of the mineral including the changes of entropy and enthalpy and the Gibbs function of free energy have been calculated. The standard values of thermodynamic functions of pseudo-malachite at T = 298.15 K are C p,m ° =(385.43±0.41)J mole −1  K −1 , Δ 0 T S m ° =(412.16±0.61)J mole −1  K −1 , Δ 0 T H m ° =(63681.5±57.0)J mole −1 , F m ° =(198.57±0.47)J mole −1  K −1 . In the low-temperature area 0 tr = (5.772 ± 0.081) J mole −1 K −1 , ΔH tr = (29.94 ± 0.42) J mole −1 .

Heavy metals and color retention by a synthesized inorganic membrane

Directory of Open Access Journals (Sweden)

A. Chougui

2014-11-01

The ceramic membranes were tested for the removal of cadmium, zinc, Methylene Blue and Malachite Green from water under a pressure of 5 bar and a treatment time of 2 h. Liquid filtration and flow tests through these membranes resulted in a rejection rate of 100% for Methylene Blue and Malachite Green. This paper also presents the ability of the tubular membrane prepared to separate heavy metals (cadmium and zinc from their synthetic aqueous solutions. The influence of the applied pressure, feed solute concentration, feed pH on the rejection of cadmium and zinc ions was studied. Retention rates of cadmium and zinc ions of 100% were observed for an initial feed concentration of 10−4 mol/L.

Au-coated ZnO nanorods on stainless steel fiber for self-cleaning solid phase microextraction-surface enhanced Raman spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Li, Bo; Shi, Yu-e; Cui, Jingcheng; Liu, Zhen; Zhang, Xiaoli; Zhan, Jinhua, E-mail: jhzhan@sdu.edu.cn

2016-06-07

Solid phase microextraction-surface enhanced Raman spectroscopy (SPME–SERS), combining the pretreatment and determination functions, has been successfully used in environmental analysis. In this work, Au-coated ZnO nanorods were fabricated on stainless steel fiber as a self-cleaning SERS-active SPME fiber. The ZnO nanorods grown on stainless steel fiber were prepared via a simple hydrothermal approach. Then the obtained nanostructures were decorated with Au nanoparticles through ion-sputtering at room temperature. The obtained SERS-active SPME fiber is a reproducible sensitivity sensor. Taking p-aminothiophenol as the probe molecule, the RSD value of the SERS-active SPME fiber was 8.9%, indicating the fiber owned good uniformity. The qualitative and quantitative detection of crystal violet and malachite green was also achieved. The log–log plot of SERS intensity to crystal violet and malachite green concentration showed a good linear relationship. Meanwhile, this SERS-active SPME fiber can achieve self-cleaning owning to the excellent photocatalytic performance of ZnO nanorods. Crystal violet was still successfully detected even after five cycles, which indicated the high reproducibility of this SERS-active SPME fiber. - Graphical abstract: Au-coated ZnO NRs on stainless steel fiber were used as SERS-active SPME fiber with good extraction effect, high SERS sensitivity. Self-cleaning function of the fiber was achieved based on the photocatalytic degradation property of ZnO nanorods by UV irradiation. - Highlights: • Au-coated ZnO nanorods on stainless steel fiber as a SERS-active SPME fiber was fabricated. • The SERS-active SPME fiber can directly extract and detect the crystal violet and malachite green. • The SERS-active SPME fiber owns good extraction effect, and high SERS sensitivity. • Self-cleaning property of the fiber were achieved based on the photocatalytic degradation property of ZnO.

Au-coated ZnO nanorods on stainless steel fiber for self-cleaning solid phase microextraction-surface enhanced Raman spectroscopy

International Nuclear Information System (INIS)

Li, Bo; Shi, Yu-e; Cui, Jingcheng; Liu, Zhen; Zhang, Xiaoli; Zhan, Jinhua

2016-01-01

Solid phase microextraction-surface enhanced Raman spectroscopy (SPME–SERS), combining the pretreatment and determination functions, has been successfully used in environmental analysis. In this work, Au-coated ZnO nanorods were fabricated on stainless steel fiber as a self-cleaning SERS-active SPME fiber. The ZnO nanorods grown on stainless steel fiber were prepared via a simple hydrothermal approach. Then the obtained nanostructures were decorated with Au nanoparticles through ion-sputtering at room temperature. The obtained SERS-active SPME fiber is a reproducible sensitivity sensor. Taking p-aminothiophenol as the probe molecule, the RSD value of the SERS-active SPME fiber was 8.9%, indicating the fiber owned good uniformity. The qualitative and quantitative detection of crystal violet and malachite green was also achieved. The log–log plot of SERS intensity to crystal violet and malachite green concentration showed a good linear relationship. Meanwhile, this SERS-active SPME fiber can achieve self-cleaning owning to the excellent photocatalytic performance of ZnO nanorods. Crystal violet was still successfully detected even after five cycles, which indicated the high reproducibility of this SERS-active SPME fiber. - Graphical abstract: Au-coated ZnO NRs on stainless steel fiber were used as SERS-active SPME fiber with good extraction effect, high SERS sensitivity. Self-cleaning function of the fiber was achieved based on the photocatalytic degradation property of ZnO nanorods by UV irradiation. - Highlights: • Au-coated ZnO nanorods on stainless steel fiber as a SERS-active SPME fiber was fabricated. • The SERS-active SPME fiber can directly extract and detect the crystal violet and malachite green. • The SERS-active SPME fiber owns good extraction effect, and high SERS sensitivity. • Self-cleaning property of the fiber were achieved based on the photocatalytic degradation property of ZnO.

Systematic Analysis of the Multiple Bioactivities of Green Tea through a Network Pharmacology Approach

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Shoude Zhang

2014-01-01

Full Text Available During the past decades, a number of studies have demonstrated multiple beneficial health effects of green tea. Polyphenolics are the most biologically active components of green tea. Many targets can be targeted or affected by polyphenolics. In this study, we excavated all of the targets of green tea polyphenolics (GTPs though literature mining and target calculation and analyzed the multiple pharmacology actions of green tea comprehensively through a network pharmacology approach. In the end, a total of 200 Homo sapiens targets were identified for fifteen GTPs. These targets were classified into six groups according to their related disease, which included cancer, diabetes, neurodegenerative disease, cardiovascular disease, muscular disease, and inflammation. Moreover, these targets mapped into 143 KEGG pathways, 26 of which were more enriched, as determined though pathway enrichment analysis and target-pathway network analysis. Among the identified pathways, 20 pathways were selected for analyzing the mechanisms of green tea in these diseases. Overall, this study systematically illustrated the mechanisms of the pleiotropic activity of green tea by analyzing the corresponding “drug-target-pathway-disease” interaction network.

Green Tea Consumption and Risk of Pancreatic Cancer: A Meta-analysis

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Jin-Long Zeng

2014-10-01

Full Text Available Emerging laboratory and animal studies indicate that green tea inhibits development and progression of pancreatic cancer, but evidence from epidemiologic studies appears inconsistent and inconclusive. A meta-analysis summarizing published case-control and cohort studies was performed to evaluate the association of green tea consumption with risk of pancreatic cancer. Pertinent studies were identified by a search of PubMed and EMBASE up to April 2014. A random-effects model was assigned to compute summary risk estimates. A total of three case-control studies and five prospective studies were included, comprising 2317 incident cases and 288209 subjects. Of them, three studies were from China and the reminders were conducted in Japan. Overall, neither high vs. low green consumption (odds ratio (OR = 0.99, 95% confidence interval [CI] = 0.78–1.25, nor an increase in green tea consumption of two cups/day (OR = 0.95, 95% CI = 0.85–1.06 was associated with risk of pancreatic cancer. The null association persisted when the analysis was stratified by sex or restricted to non-smokers. In the stratification by study location, the summary OR for the studies from China and for those from Japan was 0.77 (95% CI = 0.60–0.99 and 1.21 (95% CI = 0.94–1.54, respectively (P for differences = 0.04. Cumulative epidemiologic evidence suggests that green tea consumption is not associated with pancreatic cancer.

Dissolution of copper and iron from malachite ore and precipitation of copper sulfate pentahydrate by chemical process

OpenAIRE

H. Kokes; M.H. Morcali; E. Acma

2014-01-01

The present work describes an investigation of a chemical process for the recovery of copper and iron from malachite ore. For the dissolution of copper and iron, H2SO4 was employed as well as H2O2 as an oxidizing agent. The effects of reaction temperature and time, acid concentration, liquid-to-solid ratio and agitation rate on the copper and iron percentage were investigated. Following the steps of dissolving the copper and iron sulfate and filtering, iron (III) hydroxide was precipitated by...

Egg detection and control of tribolium castaneum (Herbst) (Coleoptera : Tenebrionidae) in powdered stored food products

International Nuclear Information System (INIS)

Dotse, Raphael Djoe Nuseli

2017-07-01

For safety and shelf-stability of powdered food products, it is important to detect and deal with any infestation during processing. The focus of this study was to detect the presence of Tribolium castaneum (Herbst) (Coleopera: Tenebionidae) eggs in powdered food products, and where present, kill them using gamma irradiation. The study was carried out at the Radiation Entomology and Pest management Centre (REPMC), Ghana Atomic Energy Commission. Basic reproductive biology of T. castaneum in four different powdered food media (Wheat flour, Roasted corn powder, also known as ‘Tombrown’ powder, Cocoa powder and Fish powder) was studied. Seven (7) different stains (Bromocresol green, Malachite green, Carbol fuchsin, Basic fuchsin, Orange ‘G”, Gentian Violet and Crystal Violet) were evaluated for their ability to differentially stain T. castaneum eggs and background food particles using the American Association of Cereal Chemist, AACC (2000) staining technique. To control any egg infestation, the effect of gamma irradiation at 200Gy on egg hatchability was evaluated. Results indicate that egg production by T. casteneum within a three day period on Wheat flour, Cocoa powder and Tombrown was not significantly different but was significantly lower on fish powder (P = 0.255). Hatchability of T. castaneum eggs in the four food media was not significantly different (P = 0.046). Gamma irradiation at 200Gy was effective in controlling egg infestation by inhibiting hatchability. Bromocresol green and Malachite green differentially stained the eggs in all the four food products. The protocols for Bromocresol green and Malachite green are effective for detection of T. castaneum eggs in powdered foods and can be incorporated into production processes. Where insect eggs are detected and none of the processing steps can eliminate them, irradiation of the packaged products at 200Gy will kill any eggs and maintain the wholesomeness and safety of the product on the shelf

Green Consumerism : an Eco-Friendly Behaviour Form Through The Green Product Consumption and Green Marketing

Directory of Open Access Journals (Sweden)

Wiwik Handayani

2017-09-01

Full Text Available This research is referred to analyse the influence of consumer attitude of green product towards purchase intention. The consumer attitude of green product is a psychological tendencies that is expressed by evaluating a certain entity with some advantage or disadvantage considerations. The problem of this research is the low of cunsumer awareness to consume green product, because the lack to comprehend the importance of green product usage for health and eco-friendly. The purpose of this research is to test the influence of consumer attitude of green products towards purchase intention. Hypothesis testing using Partial Least Square (PLS. The result of analysis show that there is influence among consumer attitude of green product towards consumer purchase intention significantly.

Green Roofs: Standardization and Quality Control of Processes in Green Construction

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Korol Elena

2017-01-01

Full Text Available The article considers the problems of standardization and quality control of processes in the construction, improvement of integrated safety of buildings and the implementation of innovative green building technologies, the use of national standards as well as international rating systems for green buildings evaluation. This is one of the priority directions in development of the modern construction. The aim of this study is the analysis of the green roof systems and international standards, which were carried out in the green building industry. The authors have studied traditional and innovative solutions of rational using natural resources and energy, the green roof system with integration of supported solar and wind energy collecting and converting devices and of irrigation system. Some studies provide evidence for the benefits of the modular green roof system in urban green space with microclimate differences. This article presents a new research which advances our knowledge of the economic and environmental services provided by the green roof system. Research reported here also considers the analysis of the Russian and international legislation of the quality control of processes in green construction.

Stable carbon and oxygen isotope ratios of malachite from the patinas of ancient bronze objects

International Nuclear Information System (INIS)

Smith, A.W.

1978-01-01

13 C/ 12 C and 18 O/ 16 O ratios have been measured for 62 samples of the mineral malachite, taken from the patinas of ancient bronze objects (from Britain, Italy, Libya and China), in order to investigate any possible relationship which may exist between the isotope ratios and the burial conditions of the objects. The results indicate that the isotope ratios are controlled by complex factors related to the climate, vegetation and soil type at the burial site. It is suggested that the technique might be used, given favourable circumstances, in the characterization of patinas and as a possible aid in the detection of synthetic patination. (author)

Towards green loyalty: the influences of green perceived risk, green image, green trust and green satisfaction

Science.gov (United States)

Chrisjatmiko, K.

2018-01-01

The paper aims to present a comprehensive framework for the influences of green perceived risk, green image, green trust and green satisfaction to green loyalty. The paper also seeks to account explicitly for the differences in green perceived risk, green image, green trust, green satisfaction and green loyalty found among green products customers. Data were obtained from 155 green products customers. Structural equation modeling was used in order to test the proposed hypotheses. The findings show that green image, green trust and green satisfaction has positive effects to green loyalty. But green perceived risk has negative effects to green image, green trust and green satisfaction. However, green perceived risk, green image, green trust and green satisfaction also seems to be a good device to gain green products customers from competitors. The contributions of the paper are, firstly, a more complete framework of the influences of green perceived risk, green image, green trust and green satisfaction to green loyalty analyses simultaneously. Secondly, the study allows a direct comparison of the difference in green perceived risk, green image, green trust, green satisfaction and green loyalty between green products customers.

Multivariate qualitative analysis of banned additives in food safety using surface enhanced Raman scattering spectroscopy.

Science.gov (United States)

He, Shixuan; Xie, Wanyi; Zhang, Wei; Zhang, Liqun; Wang, Yunxia; Liu, Xiaoling; Liu, Yulong; Du, Chunlei

2015-02-25

A novel strategy which combines iteratively cubic spline fitting baseline correction method with discriminant partial least squares qualitative analysis is employed to analyze the surface enhanced Raman scattering (SERS) spectroscopy of banned food additives, such as Sudan I dye and Rhodamine B in food, Malachite green residues in aquaculture fish. Multivariate qualitative analysis methods, using the combination of spectra preprocessing iteratively cubic spline fitting (ICSF) baseline correction with principal component analysis (PCA) and discriminant partial least squares (DPLS) classification respectively, are applied to investigate the effectiveness of SERS spectroscopy for predicting the class assignments of unknown banned food additives. PCA cannot be used to predict the class assignments of unknown samples. However, the DPLS classification can discriminate the class assignment of unknown banned additives using the information of differences in relative intensities. The results demonstrate that SERS spectroscopy combined with ICSF baseline correction method and exploratory analysis methodology DPLS classification can be potentially used for distinguishing the banned food additives in field of food safety. Copyright © 2014 Elsevier B.V. All rights reserved.

(Hevea brasiliensis) SEED PERICARP-ACTIVATED CARBON

African Journals Online (AJOL)

2012-11-03

Nov 3, 2012 ... The continuous drive to increase meat production for the protein needs of the ...... Removal of malachite green from aqueous solution using degreased ... and copper onto treated alga (Undariapinnarlifida):. Application of ...

Binding affinities of cationic dyes in the presence of activated charcoal and anionic surfactant in the premicellar region

Science.gov (United States)

Ali, Farman; Ibrahim, Muhammad; Khan, Fawad; Bibi, Iram; Shah, Syed W. H.

2018-03-01

Binding preferences of cationic dyes malachite green and methylene blue in a mixed charcoal-sodium dodecyl sulfate system have been investigated using UV-visible absorption spectroscopy. The dye adsorption shows surfactant-dependent patterns, indicating diverse modes of interactions. At low surfactant concentration, a direct binding to charcoal is preferred. Comparatively greater quantities of surfactant lead to attachment of dye-surfactant complex to charcoal through hydrophobic interactions. A simple model was employed for determination of equilibrium constant K eq and concentration of dye-surfactant ion pair N DS for both dyes. The values of binding parameters revealed that malachite green was directly adsorbed onto charcoal, whereas methylene blue was bound through surfactant monomers. The model is valid for low surfactant concentrations in the premicellar region. These findings have significance for material and environmental sciences.

Market analysis green electricity. Final report

International Nuclear Information System (INIS)

Reichmuth, Matthias

2014-01-01

In the present study the volume of the German market for green energy will be analyzed for its functionality, barriers and also its development perspectives. Besides an evaluation of actual literature sources, elaborate interviews of electricity suppliers (green energy suppliers) were realized.

CHROMATOGRAPHIC SEPARATION AND SPECTRO ...

African Journals Online (AJOL)

Four different fractions having colours yellow, grey, orange and ... Two different dyes vis a vis: methylene blue and malachite green dyes have been separated .... hydrogen carbonate of alkaline and alkaline earth metals in the samples.

Analysis on the Relationship between Green Accounting and Green Design for Enterprises

Directory of Open Access Journals (Sweden)

Jui-Che Tu

2015-05-01

Full Text Available Green design is advocated and developed in response to the increasingly deteriorating global environment, but its implementation is only based on the morality of the entrepreneurs, without economic incentive and legal restraint. As a result, green design has not been widely adopted. In recent years, the European countries, the U.S., Japan, the UN and Taiwan have successively promoted environmental accounting guidelines and required enterprises to disclose environmental improvement information, so as to improve the environment through production that will unavoidably impact product manufacturing. How product design should respond to this trend is a concern of this study. This study adopted the KJ (Kawakita Jiro method and the meta-research method to analyze the influence factors. Then, it was discussed whether green design is feasible. The results showed that the requirements of green accounting include: expanding corporate social responsibility, production cannot be exempted from environmental protection, the manufacturing of clean products can generate pollution, the external production cost should be internalized, the redesign to improve the product production process and packaging, reducing resource waste and implementing the (Reduce, Recycle, Reuse 3R policy, lifecycle assessment for all assessments and developing environmentally-friendly products, which can be solved with green design.

Investigation of structural responses of breakwaters for green water based on fluid-structure interaction analysis

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Chi-Seung Lee

2012-06-01

Full Text Available In the present study, the structural response of breakwaters installed on container carriers against green water impact loads was numerically investigated on the basis of the fluid-structure interaction analysis. A series of numerical studies is carried out to induce breakwater collapse under such conditions, whereby a widely accepted fluid-structure interaction analysis technique is adopted to realistically consider the phenomenon of green water impact loads. In addition, the structural behaviour of these breakwaters under green water impact loads is investigated simultaneously throughout the transient analysis. A verification study of the numerical results is performed using data from actual collapse incidents of breakwaters on container carriers. On the basis of the results of a series of numerical analyses, the pressure distribution of green water was accurately predicted with respect to wave mass and velocity. It is expected that the proposed analytical methodology and predicted pressure distribution could be used as a practical guideline for the design of breakwaters on container carriers.

Guest–host interactions in the alkaline bleaching of ...

Indian Academy of Sciences (India)

Administrator

cyclodextrin on the bleaching rates of triphenylmethane dyes crystal violet (CV), malachite green (MG) and rosaniline. (RA) have been investigated in alkaline medium with a view to understand the guest–host interaction in these system. 2.

Phytolith analysis for differentiating between foxtail millet (Setaria italica) and green foxtail (Setaria viridis).

Science.gov (United States)

Zhang, Jianping; Lu, Houyuan; Wu, Naiqin; Yang, Xiaoyan; Diao, Xianmin

2011-05-06

Foxtail millet (Setaria italica) is one of the oldest domesticated cereal crops in Eurasia, but identifying foxtail millets, especially in charred grains, and differentiating it from its wild ancestor, green foxtail (Setaria viridis), in the archaeobotanical remains, is still problematic. Phytolithic analysis provides a meaningful method for identifying this important crop. In this paper, the silicon structure patterns in the glumes, lemmas, and paleas from inflorescence bracts in 16 modern plants of foxtail millet and green foxtail from China and Europe are examined using light microscopy with phase-contrast and a microscopic interferometer. Our research shows that the silicon structure of ΩIII from upper lemmas and paleas in foxtail millet and green foxtail can be correspondingly divided into two groups. The size of ΩIII type phytolith of foxtail millet is bigger than that from green foxtail. Discriminant function analysis reveals that 78.4% of data on foxtail millet and 76.9% of data on green foxtail are correctly classified. This means certain morphotypes of phytoliths are relatively reliable tools for distinguishing foxtail millet from green foxtail. Our results also revealed that the husk phytolith morphologies of foxtail millets from China and Eastern Europe are markedly different from those from Western Europe. Our research gives a meaningful method of separating foxtail millet and green foxtail. The implications of these findings for understanding the history of foxtail millet domestication and cultivation in ancient civilizations are significant.

Phytolith analysis for differentiating between foxtail millet (Setaria italica and green foxtail (Setaria viridis.

Directory of Open Access Journals (Sweden)

Jianping Zhang

2011-05-01

Full Text Available Foxtail millet (Setaria italica is one of the oldest domesticated cereal crops in Eurasia, but identifying foxtail millets, especially in charred grains, and differentiating it from its wild ancestor, green foxtail (Setaria viridis, in the archaeobotanical remains, is still problematic. Phytolithic analysis provides a meaningful method for identifying this important crop. In this paper, the silicon structure patterns in the glumes, lemmas, and paleas from inflorescence bracts in 16 modern plants of foxtail millet and green foxtail from China and Europe are examined using light microscopy with phase-contrast and a microscopic interferometer. Our research shows that the silicon structure of ΩIII from upper lemmas and paleas in foxtail millet and green foxtail can be correspondingly divided into two groups. The size of ΩIII type phytolith of foxtail millet is bigger than that from green foxtail. Discriminant function analysis reveals that 78.4% of data on foxtail millet and 76.9% of data on green foxtail are correctly classified. This means certain morphotypes of phytoliths are relatively reliable tools for distinguishing foxtail millet from green foxtail. Our results also revealed that the husk phytolith morphologies of foxtail millets from China and Eastern Europe are markedly different from those from Western Europe. Our research gives a meaningful method of separating foxtail millet and green foxtail. The implications of these findings for understanding the history of foxtail millet domestication and cultivation in ancient civilizations are significant.

Purchasing green to become greener: Factors influence consumers’ green purchasing behavior

Directory of Open Access Journals (Sweden)

Hosein Vazifehdoust

2013-09-01

Full Text Available This study proposes an integrated model that combines the Theory of Reasoned Action (TRA and two categories of variables, personal and marketing, to investigate the attitudinal and behavioral decision factors to purchase green products. The model derived and tested via structural equation modeling on a sample of 374 consumers from the Guilan province in Iran. The results show that attitude is explained by consumers’ environmental concern, quality of green products, green advertising and green labeling. The results of the structural equation analysis indicate that attitude positively influences intention to purchase green products. Green purchasing intention also influences on green purchasing behavior. This paper also discusses the implications of the results for marketers and researchers.

UMTRA water sampling and analysis plan, Green River, Utah

International Nuclear Information System (INIS)

Papusch, R.

1993-12-01

The purpose of this water sampling and analysis plan (WSAP) is to provide a basis for groundwater and surface water sampling at the Green River Uranium Mill Tailing Remedial Action (UMTRA) Project site. This WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the monitoring locations

To Green or Not to Green: A Political, Economic and Social Analysis for the Past Failure of Green Logistics

Directory of Open Access Journals (Sweden)

Matthias Klumpp

2016-05-01

Full Text Available The objective of green logistics has thus far failed. For example, the share of greenhouse gas emissions by the transportation and logistics sector in Europe rose from 16.6% in 1990 to 24.3% in 2012. This article analyzes the reasons behind this failure by drawing on political, economic and business as well as social motivations and examples. At the core of this analysis are the established theorems of the Jevons paradox and the median voter (Black, Downs in combination with time-distorted preferences of voters and consumers. Adding to the hurdles of green logistics are the problems of short-term political programs and decisions versus long-term business investments in transportation and logistics. Two cases from Germany are outlined regarding this political “meddling through” with a recent 2015 truck toll decision and the support for electric trucks and vehicles. Finally, the article proposes two ways forward: public control and restriction of carbon raw materials (coal, oil, as well as public investment in low-emission transport infrastructure or biofuels as the more feasible and likely alternative.

A game theory analysis of green infrastructure stormwater management policies

Science.gov (United States)

William, Reshmina; Garg, Jugal; Stillwell, Ashlynn S.

2017-09-01

Green stormwater infrastructure has been demonstrated as an innovative water resources management approach that addresses multiple challenges facing urban environments. However, there is little consensus on what policy strategies can be used to best incentivize green infrastructure adoption by private landowners. Game theory, an analysis framework that has historically been under-utilized within the context of stormwater management, is uniquely suited to address this policy question. We used a cooperative game theory framework to investigate the potential impacts of different policy strategies used to incentivize green infrastructure installation. The results indicate that municipal regulation leads to the greatest reduction in pollutant loading. However, the choice of the "best" regulatory approach will depend on a variety of different factors including politics and financial considerations. Large, downstream agents have a disproportionate share of bargaining power. Results also reveal that policy impacts are highly dependent on agents' spatial position within the stormwater network, leading to important questions of social equity and environmental justice.

Semiconductor thin films directly from minerals—study of structural, optical, and transport characteristics of Cu2O thin films from malachite mineral and synthetic CuO

International Nuclear Information System (INIS)

Balasubramaniam, K.R.; Kao, V.M.; Ravichandran, J.; Rossen, P.B.; Siemons, W.; Ager, J.W.

2012-01-01

We demonstrate the proof-of-concept of using an abundantly occurring natural ore, malachite (Cu 2 CO 3 (OH) 2 ) to directly yield the semiconductor Cu 2 O to be used as an active component of a functional thin film based device. Cu 2 O is an archetype hole-conducting semiconductor that possesses several interesting characteristics particularly useful for solar cell applications, including low cost, non-toxicity, good hole mobility, large minority carrier diffusion length, and a direct energy gap ideal for efficient absorption. In this article, we compare the structural, optical, and electrical transport characteristics of Cu 2 O thin films grown from the natural mineral malachite and synthetic CuO targets. Growth from either source material results in single-phase, fully epitaxial cuprous oxide thin films as determined by x-ray diffraction. The films grown from malachite have strong absorption coefficients ( 10 4 cm −1 ), a direct allowed optical bandgap ( 2.4 eV), and majority carrier hole mobilities ( 35 cm 2 V −1 s −1 at room temperature) that compare well with films grown from the synthetic target as well as with previously reported values. Our work demonstrates that minerals could be useful to directly yield the active components in functional devices and suggests a route for the exploration of low cost energy conversion and storage technologies. - Highlights: ► Semiconductor thin films directly from minerals ► Chemistry and structure evolution of the films obtained from mineral target is very similar to that films obtained from high-purity synthetic targets. ► Quite interestingly, transport and optical characteristics are also found to be similar.

The SERS and TERS effects obtained by gold droplets on top of Si nanowires.

Science.gov (United States)

Becker, M; Sivakov, V; Andrä, G; Geiger, R; Schreiber, J; Hoffmann, S; Michler, J; Milenin, A P; Werner, P; Christiansen, S H

2007-01-01

We show that hemispherical gold droplets on top of silicon nanowires when grown by the vapor-liquid-solid (VLS) mechanism, can produce a significant enhancement of Raman scattered signals. Signal enhancement for a few or even just single gold droplets is demonstrated by analyzing the enhanced Raman signature of malachite green molecules. For this experiment, trenches (approximately 800 nm wide) were etched in a silicon-on-insulator (SOI) wafer along crystallographic directions that constitute sidewalls ({110} surfaces) suitable for the growth of silicon nanowires in directions with the intention that the gold droplets on the silicon nanowires can meet somewhere in the trench when growth time is carefully selected. Another way to realize gold nanostructures in close vicinity is to attach a silicon nanowire with a gold droplet onto an atomic force microscopy (AFM) tip and to bring this tip toward another gold-coated AFM tip where malachite green molecules were deposited prior to the measurements. In both experiments, signal enhancement of characteristic Raman bands of malachite green molecules was observed. This indicates that silicon nanowires with gold droplets atop can act as efficient probes for tip-enhanced Raman spectroscopy (TERS). In our article, we show that a nanowire TERS probe can be fabricated by welding nanowires with gold droplets to AFM tips in a scanning electron microscope (SEM). TERS tips made from nanowires could improve the spatial resolution of Raman spectroscopy so that measurements on the nanometer scale are possible.

Sensitivity of juvenile striped bass to chemicals used in aquaculture

Science.gov (United States)

Bills, Terry D.; Marking, Leif L.; Howe, George E.

1993-01-01

Efforts to restore anadromous striped bass (Morone saxatilis) populations by the U.S. Fish and Wildlife Service and other agencies over the past 20 years have concentrated on hatchery culture to supplement dwindling natural reproduction. Adult fish captured for artificial spawning are stressed by handling and crowding in rearing ponds and are often exposed to therapeutants, anesthetics, disinfectants, and herbicides used in fish culture. We determined the toxicity of 17 fishery chemicals (chloramine-T, erythromycin, formalin, Hyamine 3500, Roccal, malachite green, sulfamerazine, benzocaine, etomidate, Finquel (MS-222) , metomidate, quinaldine sulfate, chlorine, potassium permanganate, Aquazine, copper sulfate, and Rodeo) to striped bass fry (average weight = 1 g) in reconstituted water (total hardness 40 mg/L) at 12 degree C. The 96-h LC50's (concentration calculated to produce 50% mortality in a population) ranged from 0.129 mg/L for malachite green to 340 mg/L for erythromycin. We also determined the effects of selected levels of water temperature, hardness, and pH on the toxicity of chloramine-T, formalin, malachite green, and Roccal. There were no differences in toxicity for any of the chemicals at any water quality variable tested except for chloramine-T, which was about 25 times more toxic in soft, acid water than in soft, alkaline water. Our data show that the striped bass is as sensitive to fishery chemicals as rainbow trout (Oncorhynchus mykiss), but is generally less resistant than bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus).

Analysis of green luminescent Tb3+:Ca4GdO(BO3)3 powder phosphor

International Nuclear Information System (INIS)

Vengala Rao, B.; Rambabu, U.; Buddhudu, S.

2007-01-01

This paper reports on the emission analysis of a green luminescent Tb 3+ :Ca 4 GdO(BO 3 ) 3 powder phosphor based on the measurements of excitation, emission and lifetimes. Besides this, we have also observed an intense green emission from this powder phosphor under an UV source. The emission transitions of ( 5 D 4 →7 F 3,4,5,6 ) with λ exci =257 nm have been measured. Particularly, the green emission transition ( 5 D 4 →7 F 5 ) at 553 nm has been found to be more prominent and intense. Such green strong emission displaying powder phosphor will find applications in the development of coated screens in certain electronic systems. Apart from the emission analysis of this phosphor, XRD, SEM and FTIR studies have also been carried out in order to understand the structural details of it

Multi-Hierarchical Gray Correlation Analysis Applied in the Selection of Green Building Design Scheme

Science.gov (United States)

Wang, Li; Li, Chuanghong

2018-02-01

As a sustainable form of ecological structure, green building is widespread concerned and advocated in society increasingly nowadays. In the survey and design phase of preliminary project construction, carrying out the evaluation and selection of green building design scheme, which is in accordance with the scientific and reasonable evaluation index system, can improve the ecological benefits of green building projects largely and effectively. Based on the new Green Building Evaluation Standard which came into effect on January 1, 2015, the evaluation index system of green building design scheme is constructed taking into account the evaluation contents related to the green building design scheme. We organized experts who are experienced in construction scheme optimization to mark and determine the weight of each evaluation index through the AHP method. The correlation degree was calculated between each evaluation scheme and ideal scheme by using multilevel gray relational analysis model and then the optimal scheme was determined. The feasibility and practicability of the evaluation method are verified by introducing examples.

Web-based automation of green building rating index and life cycle cost analysis

Science.gov (United States)

Shahzaib Khan, Jam; Zakaria, Rozana; Aminuddin, Eeydzah; IzieAdiana Abidin, Nur; Sahamir, Shaza Rina; Ahmad, Rosli; Nafis Abas, Darul

2018-04-01

Sudden decline in financial markets and economic meltdown has slow down adaptation and lowered interest of investors towards green certified buildings due to their higher initial costs. Similarly, it is essential to fetch investor’s attention towards more development of green buildings through automated tools for the construction projects. Though, historical dearth is found on the automation of green building rating tools that brings up an essential gap to develop an automated analog computerized programming tool. This paper present a proposed research aim to develop an integrated web-based automated analog computerized programming that applies green building rating assessment tool, green technology and life cycle cost analysis. It also emphasizes to identify variables of MyCrest and LCC to be integrated and developed in a framework then transformed into automated analog computerized programming. A mix methodology of qualitative and quantitative survey and its development portray the planned to carry MyCrest-LCC integration to an automated level. In this study, the preliminary literature review enriches better understanding of Green Building Rating Tools (GBRT) integration to LCC. The outcome of this research is a pave way for future researchers to integrate other efficient tool and parameters that contributes towards green buildings and future agendas.

Chemical and colour quenching in liquid scintillation counting; Estudio de la extincion quimica y por color en centelleo liquido

Energy Technology Data Exchange (ETDEWEB)

Scott, P E; Grau, A

1987-07-01

Chemical and colour quenching for H-3 and C-14 was studied. The method includes spectral analysis of colouring agents; methyl red, (4'-dimethylamine-azobenzene 2-carboxylic acid) dimethyl yellow (4'-dimethylamine-azobenzene) and malachite green (methane, bis .(4-dimethyl aminophenyl) - (phenyl)). External standard channels ratio was applied for the liquid scintillation counting of samples. The introduction of an isolated external standard seems to be a strong tool for the correction of chemical and colour quenching curves. (Author) 12 refs.

Chemical and colour quenching in liquid scintillation counting; Estudio de la extincion quimica y por color en centelleo liquido

Energy Technology Data Exchange (ETDEWEB)

Scott, P. E.; Grau, A.

1987-07-01

Chemical and colour quenching for H-3 and C-14 was studied. The method includes spectral analysis of colouring agents; methyl red, (4'-dimethylamine-azobenzene 2-carboxylic acid) dimethyl yellow (4'-dimethylamine-azobenzene) and malachite green (methane, bis .(4-dimethyl aminophenyl) - (phenyl)). External standard channels ratio was applied for the liquid scintillation counting of samples. The introduction of an isolated external standard seems to be a strong tool for the correction of chemical and colour quenching curves. (Author) 12 refs.

Chemical and colour quenching in liquid scintillation counting

International Nuclear Information System (INIS)

Scott G, P. E.; Grau M, A.

1987-01-01

Chemical and colour quenching for H-3 and C-14 was studied. The method includes spectral analysis of colouring agents; methyl red, (4'-dimethylamine-azobenzene 2-carboxylic acid) dimethyl yellow (4'-dimethylamine-azobenzene) and malachite green (methane, bis .(4-dimethyl aminophenyl) - (phenyl)). External standard channels ratio was applied for the liquid scintillation counting of samples. The introduction of an isolated external standard seems to be a strong tool for the correction of chemical and colour quenching curves. (Author) 12 refs

Validation of a new technique to detect Cryptosporidium spp. oocysts in bovine feces.

Science.gov (United States)

Inácio, Sandra Valéria; Gomes, Jancarlo Ferreira; Oliveira, Bruno César Miranda; Falcão, Alexandre Xavier; Suzuki, Celso Tetsuo Nagase; Dos Santos, Bianca Martins; de Aquino, Monally Conceição Costa; de Paula Ribeiro, Rafaela Silva; de Assunção, Danilla Mendes; Casemiro, Pamella Almeida Freire; Meireles, Marcelo Vasconcelos; Bresciani, Katia Denise Saraiva

2016-11-01

Due to its important zoonotic potential, cryptosporidiosis arouses strong interest in the scientific community, because, it was initially considered a rare and opportunistic disease. The parasitological diagnosis of the causative agent of this disease, the protozoan Cryptosporidium spp., requires the use of specific techniques of concentration and permanent staining, which are laborious and costly, and are difficult to use in routine laboratory tests. In view of the above, we conducted the feasibility, development, evaluation and intralaboratory validation of a new parasitological technique for analysis in optical microscopy of Cryptosporidium spp. oocysts, called TF-Test Coccidia, using fecal samples from calves from the city of Araçatuba, São Paulo. To confirm the aforementioned parasite and prove the diagnostic efficiency of the new technique, we used two established methodologies in the scientific literature: parasite concentration by centrifugal sedimentation and negative staining with malachite green (CSN-Malachite) and Nested-PCR. We observed good effectiveness of the TF-Test Coccidia technique, being statistically equivalent to CSN-Malachite. Thus, we verified the effectiveness of the TF-Test Coccidia parasitological technique for the detection of Cryptosporidium spp. oocysts and observed good concentration and morphology of the parasite, with a low amount of debris in the fecal smear. Copyright © 2016 Elsevier B.V. All rights reserved.

Use practices of antimicrobials and other compounds by shrimp and fish farmers in Northern Vietnam

DEFF Research Database (Denmark)

Thi Kim Chi, Tran; Clausen, Jesper H.; Van, Phan Thi

2017-01-01

that 20 different antimicrobial products were used for disease prevention and treatment in shrimp and marine fish culture. Banned products used included chloramphenicol, enrofloxacin and malachite green. Cage fish farmers said they purchased antimicrobial tablets readily available at a local pharmacy...

Femtosecond pump probe spectroscopy for the study of energy transfer of light-harvesting complexes from extractions of spinach leaves

CSIR Research Space (South Africa)

Ombinda-Lemboumba, Saturnin

2009-09-01

Full Text Available been implemented at the CSIR National Laser Centre and has been applied to investigate energy transfer processes in different parts of photosynthetic systems. In this paper, researchers report on the first results obtained with Malachite green as a...

Greening Reversed-Phase Liquid Chromatography Methods Using Alternative Solvents for Pharmaceutical Analysis

Directory of Open Access Journals (Sweden)

Moussa Yabré

2018-05-01

Full Text Available The greening of analytical methods has gained increasing interest in the field of pharmaceutical analysis to reduce environmental impacts and improve the health safety of analysts. Reversed-phase high-performance liquid chromatography (RP-HPLC is the most widely used analytical technique involved in pharmaceutical drug development and manufacturing, such as the quality control of bulk drugs and pharmaceutical formulations, as well as the analysis of drugs in biological samples. However, RP-HPLC methods commonly use large amounts of organic solvents and generate high quantities of waste to be disposed, leading to some issues in terms of ecological impact and operator safety. In this context, greening HPLC methods is becoming highly desirable. One strategy to reduce the impact of hazardous solvents is to replace classically used organic solvents (i.e., acetonitrile and methanol with greener ones. So far, ethanol has been the most often used alternative organic solvent. Others strategies have followed, such as the use of totally aqueous mobile phases, micellar liquid chromatography, and ionic liquids. These approaches have been well developed, as they do not require equipment investments and are rather economical. This review describes and critically discusses the recent advances in greening RP-HPLC methods dedicated to pharmaceutical analysis based on the use of alternative solvents.

Green Power voluntary purchases: Price elasticity and policy analysis

International Nuclear Information System (INIS)

Mewton, Ross T.; Cacho, Oscar J.

2011-01-01

Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of ±68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales.

Green Power voluntary purchases: Price elasticity and policy analysis

Energy Technology Data Exchange (ETDEWEB)

Mewton, Ross T., E-mail: rtmewton@hotmail.co [University of New England (Australia); Cacho, Oscar J. [School of Business Economics and Public Policy, School of Economics, University of New England, Armidale, NSW 2351 (Australia)

2011-01-15

Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of {+-}68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales.

Green Power voluntary purchases. Price elasticity and policy analysis

Energy Technology Data Exchange (ETDEWEB)

Mewton, Ross T. [University of New England (Australia); Cacho, Oscar J. [School of Business Economics and Public Policy, School of Economics, University of New England, Armidale, NSW 2351 (Australia)

2011-01-15

Green Power schemes offer electricity from renewable energy sources to customers for a higher price than ordinary electricity. This study examines the demand characteristics of Green Power in Australia and policies which could increase its sales. A sample of 250 pooled time series and cross sectional observations was used to estimate a statistically significant elasticity of demand for Green Power with respect to price of -0.96 with a 95% confidence interval of {+-}68%. The wide variation in market penetration between jurisdictions and between countries for Green Power, and the low awareness of Green Power found by surveys indicate that Green Power sales could be increased by appropriate marketing and government policies. The most cost effective means to increase sales was found to be advertising campaigns although only one Australian example was found, in the state of Victoria in 2005. It was also found that full tax deductibility of the Green Power premium to residential customers, exemption from the Goods and Services Tax and a tax rebate for Green Power are all probably less cost effective for promoting sales than direct government purchase of Green Power, in terms of cost per unit of increased sales. (author)

Green lights

DEFF Research Database (Denmark)

Fisker, Peter Kielberg

This study investigates the effect of drought on economic activity globally using remote sensing data. In particular, predicted variation in greenness is correlated with changes in the density of artificial light observed at night on a grid of 0.25 degree latitude-longitude pixels. I define drought...... as greenness estimated by lagged variation in monthly rainfall and temperature. This definition of drought performs well in identifying self-reported drought events since 2000 compared with measures of drought that do not take greenness into account, and the subsequent analysis indicates that predicted...... variation in greenness is positively associated with year-on-year changes in luminosity: If a unit of observation experiences a predicted variation in greenness that lies 1 standard deviation below the global mean, on average 1.5 - 2.5 light pixels out of 900 are extinguished that year. Finally, an attempt...

Mapping the Field: A Bibliometric Analysis of Green Innovation

Directory of Open Access Journals (Sweden)

Gema Albort-Morant

2017-06-01

Full Text Available The topic of green innovation (GI has increasingly attained organizational relevance due to its contribution to the satisfaction of environmental needs while concurrently enabling companies to differentiate themselves from their competitors, and hence attain sustainable competitive advantages. In this context, we conducted a detailed analysis of 618 papers on green innovation from the Web of Science (WoS database for the 1971–2015 period. This paper develops a bibliometric analysis with the aim of assessing the key papers in the field and identifying the most substantive contributions to the literature. This study presents the following findings: (i the chronological development of the discipline; (ii the research trends and popular issues in this field; (iii the antecedent variables acting as key drivers of GI in these studies; and (iv the main outcomes of GI. Therefore, this paper provides the past, the present and the potential future of this specific topic and serves as an orientation and guide for researchers who are new to the topic of GI; it also enhances their knowledge concerning which journals, authors and articles they may consult while creating their theoretical framework or designing future research models.

Current trends in green liquid chromatography for the analysis of pharmaceutically active compounds in the environmental water compartments.

Science.gov (United States)

Shaaban, Heba; Górecki, Tadeusz

2015-01-01

Green analytical chemistry is an aspect of green chemistry which introduced in the late nineties. The main objectives of green analytical chemistry are to obtain new analytical technologies or to modify an old method to incorporate procedures that use less hazardous chemicals. There are several approaches to achieve this goal such as using environmentally benign solvents and reagents, reducing the chromatographic separation times and miniaturization of analytical devices. Traditional methods used for the analysis of pharmaceutically active compounds require large volumes of organic solvents and generate large amounts of waste. Most of them are volatile and harmful to the environment. With the awareness about the environment, the development of green technologies has been receiving increasing attention aiming at eliminating or reducing the amount of organic solvents consumed everyday worldwide without loss in chromatographic performance. This review provides the state of the art of green analytical methodologies for environmental analysis of pharmaceutically active compounds in the aquatic environment with special emphasis on strategies for greening liquid chromatography (LC). The current trends of fast LC applied to environmental analysis, including elevated mobile phase temperature, as well as different column technologies such as monolithic columns, fully porous sub-2 μm and superficially porous particles are presented. In addition, green aspects of gas chromatography (GC) and supercritical fluid chromatography (SFC) will be discussed. We pay special attention to new green approaches such as automation, miniaturization, direct analysis and the possibility of locating the chromatograph on-line or at-line as a step forward in reducing the environmental impact of chromatographic analyses. Copyright © 2014 Elsevier B.V. All rights reserved.

Central Region Green Infrastructure

Data.gov (United States)

Minnesota Department of Natural Resources — This Green Infrastructure data is comprised of 3 similar ecological corridor data layers ? Metro Conservation Corridors, green infrastructure analysis in counties...

Browse Title Index

African Journals Online (AJOL)

Items 901 - 950 of 1255 ... Vol 10, No 1 (2004), PRODUCTION OF MALACHITE GREEN BY OXIDATION OF ITS ... Prospects of chemically deposited CoS-CU2S coatings for solar ... Vol 11, No 2 (2005), Protective effects of Dried Flower Extract of ...

Green Power Procurement Library | Energy Analysis | NREL

Science.gov (United States)

., and E.S. Brown. 2006. Utility-Marketer Partnerships: An Effective Strategy for Marketing Green Power Reduction Programs. Local Government Climate and Energy Strategy Series. EPA 430-R-09-045. Green Power Developing New Renewable Energy Projects. NREL/TP-6A20-51904. July. Natural Marketing Institute. 2011

Green Campus Study by using 10 UNEP’s Green University Toolkit Criteria in IPB Dramaga Campus

Science.gov (United States)

Sisriany, Saraswati; Sitti Fatimah, Indung

2017-10-01

Campus landscape is an important part of campus life, because it is regarded as a physical manifestation of the value of a college. Green campus is a concept to build sustainable living practices that are environmentally friendly in educational institutions around the world, including in IPB Dramaga Campus. The main objective of this study is to identified and analyze IPB Dramaga Campus sustainability used green campus criteria from UNEP (United Nations Environment Programme). The methods stages are data collection, analysis and assessment, and recommendation as the synthesis. All the data analyzed with gap analysis, then it assess with Likert Scale scoring. The results showed that green level of IPB Dramaga Campus is classified as Moderate, with total score 32. The result from each criterias are, Energy, Carbon and Climate Change is Moderate; Water is Not Good; Waste is Moderate; Biodiversity and Ecosystem Services is Very Good; Planning Design & Development is Good; Procurement is Moderate; Green Office is Very Not Good; Green Lab is Moderate; Green IT is Good; and Transport is Good. The Green Level of IPB Dramaga Campus will reach Very Good if these recommendation of strategies applied. The strategies are Green Office, Green Campus Audit, Green Champion, Green Financial Strategies, Water Treatment, Green Lab dan Off Campus Transportation.

Green Transformational Leadership and Green Performance: The Mediation Effects of Green Mindfulness and Green Self-Efficacy

Directory of Open Access Journals (Sweden)

Yu-Shan Chen

2014-09-01

Full Text Available No prior literature explores the influence of green transformational leadership on green performance, thus, this study develops a novel research framework to fill the research gap. This study investigates the influence of green transformational leadership on green performance and discusses the mediation effects of green mindfulness and green self-efficacy by means of structural equation modeling (SEM. The results indicate that green transformational leadership positively influences green mindfulness, green self-efficacy, and green performance. Moreover, this study demonstrates that the positive relationship between green transformational leadership and green performance is partially mediated by the two mediators: green mindfulness and green self-efficacy. It means that green transformational leadership can not only directly affect green performance positively but also indirectly affect it positively through green mindfulness and green self-efficacy. Therefore, firms need to raise their green transformational leadership, green mindfulness, and green self-efficacy to increase their green performance.

Refinement of the crystal structure of malachite, Cu2(OH)2CO3, by neutron diffraction

International Nuclear Information System (INIS)

Zigan, F.; Joswig, W.; Schuster, H.D.; Mason, S.A.

1977-01-01

The crystal structure of malachite is refined (R = 0,021) with the intensity values of 635 independent neutron reflexions from a single crystal, rather free from absorption and extinction. Concerning the structural geometry, no essential deviations occur from the known results of x-ray diffraction. The thermal elongations are generally largest about the normal to the (201) layers, between which the bonding is relatively weak. In both of the (medium, bent) OH...O hydrogen bonds, the anisotropic thermal parameters, converted according to the riding model, are - with certain restrictions - in agreement with the measured infrared spectrum as well as with frequencies and directions of the proton vibration calculated from the bonding geometry on the basis of a theoretical model. (orig.) [de

Gum ghatti and poly(acrylamide-co-acrylic acid) based biodegradable hydrogel-evaluation of the flocculation and adsorption properties

CSIR Research Space (South Africa)

Mittal, H

2015-10-01

Full Text Available removal of cationic dyes from the aqueous solutions and it was found to adsorb 96% of malachite green and 99% of methyl violet. Finally, the hydrogel polymer was subjected to biodegradation using the composting method and 91.77% degradation was achieved...

Optical Determination of Lead Chrome Green in Green Tea by Fourier Transform Infrared (FT-IR Transmission Spectroscopy.

Directory of Open Access Journals (Sweden)

Xiaoli Li

Full Text Available The potential of Fourier transform infrared (FT-IR transmission spectroscopy for determination of lead chrome green in green tea was investigated based on chemometric methods. Firstly, the qualitative analysis of lead chrome green in tea was performed based on partial least squares discriminant analysis (PLS-DA, and the correct rate of classification was 100%. And then, a hybrid method of interval partial least squares (iPLS regression and successive projections algorithm (SPA was proposed to select characteristic wavenumbers for the quantitative analysis of lead chrome green in green tea, and 19 wavenumbers were obtained finally. Among these wavenumbers, 1384 (C = C, 1456, 1438, 1419(C = N, and 1506 (CNH cm-1 were the characteristic wavenumbers of lead chrome green. Then, these 19 wavenumbers were used to build determination models. The best model was achieved by least squares support vector machine (LS-SVMalgorithm with high coefficient of determination and low root-mean square error of prediction set (R2p = 0.864 and RMSEP = 0.291. All these results indicated the feasibility of IR spectra for detecting lead chrome green in green tea.

Molecular diversity and population structure of Chinese green foxtail [Setaria viridis (L.) Beauv.] revealed by microsatellite analysis.

Science.gov (United States)

Jia, Guanqing; Shi, Shenkui; Wang, Chunfang; Niu, Zhengang; Chai, Yang; Zhi, Hui; Diao, Xianmin

2013-09-01

Green foxtail (Setaria viridis) is a new model plant for the genomic investigation of C4 photosynthesis biology. As the ancestor of foxtail millet (Setaria italica), an ancient cereal of great importance in arid regions of the world, green foxtail is crucial for the study of domestication and evolution of this ancient crop. In the present study, 288 green foxtail accessions, which were collected from all geographical regions of China, were analysed using 77 simple sequence repeats (SSRs) that cover the whole genome. A high degree of molecular diversity was detected in these accessions, with an average of 33.5 alleles per locus. Two clusters, which were inconsistent with the distribution of eco-geographical regions in China, were inferred from STRUCTURE, Neighbor-Joining, and principal component analysis, indicating a partially mixed distribution of Chinese green foxtails. The higher subpopulation diversity was from accessions mainly collected from North China. A low level of linkage disequilibrium was observed in the green foxtail genome. Furthermore, a combined analysis of green foxtail and foxtail millet landraces was conducted, and the origin and domestication of foxtail millet was inferred in North China.

Dissolution of copper and iron from malachite ore and precipitation of copper sulfate pentahydrate by chemical process

Directory of Open Access Journals (Sweden)

H. Kokes

2014-03-01

Full Text Available The present work describes an investigation of a chemical process for the recovery of copper and iron from malachite ore. For the dissolution of copper and iron, H2SO4 was employed as well as H2O2 as an oxidizing agent. The effects of reaction temperature and time, acid concentration, liquid-to-solid ratio and agitation rate on the copper and iron percentage were investigated. Following the steps of dissolving the copper and iron sulfate and filtering, iron (III hydroxide was precipitated by adjusting the pH level of the solution. Subsequently, copper sulfate pentahydrate was obtained by using various precipitants (i.e. ethanol, methanol and sulfuric acid.

Screen-Printed Electrodes Modified with "Green" Metals for Electrochemical Stripping Analysis of Toxic Elements.

Science.gov (United States)

Economou, Anastasios

2018-03-29

This work reviews the field of screen-printed electrodes (SPEs) modified with "green" metals for electrochemical stripping analysis of toxic elements. Electrochemical stripping analysis has been established as a useful trace analysis technique offering many advantages compared to competing optical techniques. Although mercury has been the preferred electrode material for stripping analysis, the toxicity of mercury and the associated legal requirements in its use and disposal have prompted research towards the development of "green" metals as alternative electrode materials. When combined with the screen-printing technology, such environment-friendly metals can lead to disposable sensors for trace metal analysis with excellent operational characteristics. This review focuses on SPEs modified with Au, Bi, Sb, and Sn for stripping analysis of toxic elements. Different modification approaches (electroplating, bulk modification, use of metal precursors, microengineering techniques) are considered and representative applications are described. A developing related field, namely biosensing based on stripping analysis of metallic nanoprobe labels, is also briefly mentioned.

The Influence of Green Marketing on Green Satisfaction Mediated By Perceived Quality and Its Impact to Green Trust in Injection Motorcycle

Directory of Open Access Journals (Sweden)

Shelvy Kurniawan

2014-09-01

Full Text Available Currently, motorcycle manufacturers are increasingly motivated to replace their motorcycle into fuel injection products. The growing concern from the consumers to the environment and the regulations of emission standards, that is Euro 3, for motorcycle industry is being finalized in the Ministry of Environment in order to be implemented in Indonesia. Through this research, the writer will examine the effect of green marketing on perceived quality, green satisfaction, and green trust, the effect of perceived quality on green satisfaction, and the effect of green satisfaction on green trust. Those effects needs to be investigated in order to know how far the effects of green marketing and to ensure whether green marketing is well accepted or not by the market in motorcycle industry. Scope of this research is also limited to the user of fuel injection motorcycle in Jakarta for Honda and Yamaha who involved as decision maker when the motorcycle is purchased. Sampling technique used in this research is quota sampling and the analysis method is structural equation modeling (SEM. The findings of this research are: green marketing has a significant direct effect on perceived quality, perceived quality has a significant direct effect on green satisfaction, green satisfaction has a significant direct effect on green trust, green marketing has a significant direct and indirect effect on green satisfaction, and green marketing has a significant direct and indirect effect on green trust. All of those effects are found to be positive effects.

Evaluation of sample extraction methods for proteomics analysis of green algae Chlorella vulgaris.

Science.gov (United States)

Gao, Yan; Lim, Teck Kwang; Lin, Qingsong; Li, Sam Fong Yau

2016-05-01

Many protein extraction methods have been developed for plant proteome analysis but information is limited on the optimal protein extraction method from algae species. This study evaluated four protein extraction methods, i.e. direct lysis buffer method, TCA-acetone method, phenol method, and phenol/TCA-acetone method, using green algae Chlorella vulgaris for proteome analysis. The data presented showed that phenol/TCA-acetone method was superior to the other three tested methods with regards to shotgun proteomics. Proteins identified using shotgun proteomics were validated using sequential window acquisition of all theoretical fragment-ion spectra (SWATH) technique. Additionally, SWATH provides protein quantitation information from different methods and protein abundance using different protein extraction methods was evaluated. These results highlight the importance of green algae protein extraction method for subsequent MS analysis and identification. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Promotion Strategy of Green Construction Materials: A Path Analysis Approach

Directory of Open Access Journals (Sweden)

Chung-Fah Huang

2015-10-01

Full Text Available As one of the major materials used in construction, cement can be very resource-consuming and polluting to produce and use. Compared with traditional cement processing methods, dry-mix mortar is more environmentally friendly by reducing waste production or carbon emissions. Despite the continuous development and promotion of green construction materials, only a few of them are accepted or widely used in the market. In addition, the majority of existing research on green construction materials focuses more on their physical or chemical characteristics than on their promotion. Without effective promotion, their benefits cannot be fully appreciated and realized. Therefore, this study is conducted to explore the promotion of dry-mix mortars, one of the green materials. This study uses both qualitative and quantitative methods. First, through a case study, the potential of reducing carbon emission is verified. Then a path analysis is conducted to verify the validity and predictability of the samples based on the technology acceptance model (TAM in this study. According to the findings of this research, to ensure better promotion results and wider application of dry-mix mortar, it is suggested that more systematic efforts be invested in promoting the usefulness and benefits of dry-mix mortar. The model developed in this study can provide helpful references for future research and promotion of other green materials.

The Promotion Strategy of Green Construction Materials: A Path Analysis Approach.

Science.gov (United States)

Huang, Chung-Fah; Chen, Jung-Lu

2015-10-14

As one of the major materials used in construction, cement can be very resource-consuming and polluting to produce and use. Compared with traditional cement processing methods, dry-mix mortar is more environmentally friendly by reducing waste production or carbon emissions. Despite the continuous development and promotion of green construction materials, only a few of them are accepted or widely used in the market. In addition, the majority of existing research on green construction materials focuses more on their physical or chemical characteristics than on their promotion. Without effective promotion, their benefits cannot be fully appreciated and realized. Therefore, this study is conducted to explore the promotion of dry-mix mortars, one of the green materials. This study uses both qualitative and quantitative methods. First, through a case study, the potential of reducing carbon emission is verified. Then a path analysis is conducted to verify the validity and predictability of the samples based on the technology acceptance model (TAM) in this study. According to the findings of this research, to ensure better promotion results and wider application of dry-mix mortar, it is suggested that more systematic efforts be invested in promoting the usefulness and benefits of dry-mix mortar. The model developed in this study can provide helpful references for future research and promotion of other green materials.

Determination of rhenium in ores of complex composition by the kinetic method

Energy Technology Data Exchange (ETDEWEB)

Pavlova, L G; Gurkina, T V [Kazakhskij Gosudarstvennyj Univ., Alma-Ata (USSR); Tsentral' naya Lab. Yuzhno-Kazakhstanskogo Geologicheskogo Upravleniya, Alma-Ata (USSR))

1979-09-01

The kinetic rhenium determination method is proposed based on rhenium catalytic effect in the reaction of malachite green with thiourea. The accompanying elements, excluding molybdenum, do not interfere with the rhenium determination at their concentration of up to 0.1 M. The interfering influence of molybdenum can be eliminated by addition of tartaric acid to the solution up to the concentration of 0.1 M. This enables to determine rhenium in presence of 1000-fold quantity of molybdenum. The method is applicable for the analysis of complex copper-zinc sulphide ores.

Acoustic analysis of warp potential of green ponderosa pine lumber

Science.gov (United States)

Xiping Wang; William T. Simpson

2005-01-01

This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 ft) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of...

Investigation of nanoscale structures by small-angle X-ray scattering in a radiochromic dosimeter

DEFF Research Database (Denmark)

Skyt, Peter Sandegaard; Jensen, Grethe Vestergaard; Wahlstedt, Isak Hannes

2014-01-01

This study examines the nanoscale structures in a radiochromic dosimeter that was based on leuco-malachite-green dye and the surfactant sodium dodecyl sulfate (SDS) suspended in a gelatin matrix. Small-angle X-ray scattering was used to investigate the structures of a range of compositions...

Treatment of trichodiniasis in eel ( Anguilla anguilla ) reared in recirculation systems in Denmark : alternatives to formaldehyde

DEFF Research Database (Denmark)

Madsen, H.C.K.; Buchmann, Kurt; Mellergaard, Stig

2000-01-01

parasiticidal effect: acriflavin (25 ppm), bithionol (0.1 ppm), chloramine T (50 ppm), Detarox AP(R) (45 ppm), malachite green (1 ppm), raw garlic (200 ppm), potassium permanganate (20 ppm) and Virkon PF(R) vet. (20 ppm). Preliminary screening revealed that the anthelmintic, bithionol, and the decomposable...

Evaluation of medicated feeds with antiparasitical and immune-enhanced Chinese herbal medicines against Ichthyophthirius multifiliis in grass carp (Ctenopharyngodon idellus)

Science.gov (United States)

Ichthyophthirius multifiliis (Ich) is a widespread ciliated ectoparasite and results in severe economic loss in the aquaculture industry. Since malachite green was banned for using in food fish due to its carcinogenic and teratogenic effects on human, the search of alternative drug to treat I. multi...

Laboratory Evaluation of the Clean Earth Technologies Decontamination Solutions for Chemical and Biological Agents

Science.gov (United States)

2008-01-01

TA. The DAAMs tubes are analyzed using a Marks UNITY/ULTRA thermal desorption system coupled to an Agilent 6890N gas chromatography -mass selective...tryptic- soy broth (TSB) or tryptic- soy agar (TSA). Frozen stock of bacterial cells, stored at -80 ’C in TSB supplemented with glycerol to a final...NNRidl) were prepared, heat-treated and ethanol-treated before staining with Malachite Green and viewed under oil immersion lens. The green to dark blue

Preparation and Photocatalytic Property of TiO2/Diatomite-Based Porous Ceramics Composite Materials

Directory of Open Access Journals (Sweden)

Shuilin Zheng

2012-01-01

Full Text Available The diatomite-based porous ceramics was made by low-temperature sintering. Then the nano-TiO2/diatomite-based porous ceramics composite materials were prepared by hydrolysis deposition method with titanium tetrachloride as the precursor of TiO2 and diatomite-based porous as the supporting body of the nano-TiO2. The structure and microscopic appearance of nano-TiO2/diatomite-based porous ceramics composite materials was characterized by XRD and SEM. The photocatalytic property of the composite was investigated by the degradation of malachite green. Results showed that, after calcination at 550°C, TiO2 thin film loaded on the diatomite-based porous ceramics is anatase TiO2 and average grain size of TiO2 is about 10 nm. The degradation ratio of the composite for 5 mg/L malachite green solution reached 86.2% after irradiation for 6 h under ultraviolet.

Femtosecond pump probe spectroscopy for the study of energy transfer of light-harvesting complexes from extractions of spinach leaves

Directory of Open Access Journals (Sweden)

L. van Rensburg

2010-01-01

Full Text Available Measurements of ultrafast transient processes, of temporal durations in the picosecond and femtosecond regime, are made possible by femtosecond pump probe transient absorption spectroscopy. Such an ultrafast pump probe transient absorption setup has been implemented at the CSIR National Laser Centre and has been applied to investigate energy transfer processes in different parts of photosynthetic systems. In this paper we report on our first results obtained with Malachite green as a benchmark. Malachite green was chosen because the lifetime of its excited state is well known. We also present experimental results of the ultrafast energy transfer of light-harvesting complexes in samples prepared from spinach leaves. Various pump wavelengths in the range 600–680 nm were used; the probe was a white light continuum spanning 420–700 nm. The experimental setup is described in detail in this paper. Results obtained with these samples are consistent with those expected and achieved by other researchers in this field.

Synthesis of Bismuth Stannate Nanoparticles with High Photocatalytic Activity under the Visible Light Irradiation

Directory of Open Access Journals (Sweden)

G. Gnanamoorthy

2017-06-01

Full Text Available Malachite Green is one of the most important organic dye, it contains triphenylmethane groups and it has been widely used for many industries. The hazardous dyes were rapidly act on immune and reproductive systems with carcinogenic effect of human health. Different methods were used for the hazardous removal in various industries, such as photocatalysis, biological treatment and adsorption process. The bismuth stannate nanoparticles have special properties of the hydrogen storage, biomolecule detection, gas sensors and catalysis. The bismuth stannate nanoparticles can be used for the degradation of organic pollutants and bismuth stannate is an important ternary oxide semiconductor with a wide band gap material. The composites were synthesized by a hydrothermal method, the obtained product was characterized by XRD, Raman, the morphology structure was confirmed by scanning electron microscopy and optical properties were carried out by DRS-UV-Vis spectroscopy. The excellent photocatalytic performance of the catalyst was evaluated by malachite green under the visible light.

Valuation of Green Walls and Green Roofs as Soundscape Measures: Including Monetised Amenity Values Together with Noise-attenuation Values in a Cost-benefit Analysis of a Green Wall Affecting Courtyards

Science.gov (United States)

Veisten, Knut; Smyrnova, Yuliya; Klæboe, Ronny; Hornikx, Maarten; Mosslemi, Marjan; Kang, Jian

2012-01-01

Economic unit values of soundscape/acoustic effects have been based on changes in the number of annoyed persons or on decibel changes. The normal procedure has been the application of these unit values to noise-attenuation measures affecting the noisier façade of a dwelling. Novel modular vegetation-based soundscape measures, so-called green walls, might be relevant for both noisy and quieter areas. Moreover, their benefits will comprise noise attenuation as well as non-acoustic amenity effects. One challenge is to integrate the results of some decades of non-acoustic research on the amenity value of urban greenery into design of the urban sound environment, and incorporate these non-acoustic properties in the overall economic assessment of noise control and overall sound environment improvement measures. Monetised unit values for green walls have been included in two alternative cases, or demonstration projects, of covering the entrances to blocks of flats with a green wall. Since these measures improve the noise environment on the quiet side of the dwellings and courtyards, not the most exposed façade, adjustment factors to the nominal quiet side decibel reductions to arrive at an estimate of the equivalent overall acoustic improvement have been applied. A cost-benefit analysis of the green wall case indicates that this measure is economically promising, when valuing the noise attenuation in the quieter area and adding the amenity/aesthetic value of the green wall. PMID:23202816

Valuation of Green Walls and Green Roofs as Soundscape Measures: Including Monetised Amenity Values Together with Noise-attenuation Values in a Cost-benefit Analysis of a Green Wall Affecting Courtyards

Directory of Open Access Journals (Sweden)

Jian Kang

2012-10-01

Full Text Available Economic unit values of soundscape/acoustic effects have been based on changes in the number of annoyed persons or on decibel changes. The normal procedure has been the application of these unit values to noise-attenuation measures affecting the noisier façade of a dwelling. Novel modular vegetation-based soundscape measures, so-called green walls, might be relevant for both noisy and quieter areas. Moreover, their benefits will comprise noise attenuation as well as non-acoustic amenity effects. One challenge is to integrate the results of some decades of non-acoustic research on the amenity value of urban greenery into design of the urban sound environment, and incorporate these non-acoustic properties in the overall economic assessment of noise control and overall sound environment improvement measures. Monetised unit values for green walls have been included in two alternative cases, or demonstration projects, of covering the entrances to blocks of flats with a green wall. Since these measures improve the noise environment on the quiet side of the dwellings and courtyards, not the most exposed façade, adjustment factors to the nominal quiet side decibel reductions to arrive at an estimate of the equivalent overall acoustic improvement have been applied. A cost-benefit analysis of the green wall case indicates that this measure is economically promising, when valuing the noise attenuation in the quieter area and adding the amenity/aesthetic value of the green wall.

Individual preferences revelation mechanism and incentive to choose green electricity: an analysis of the consumer decision process

International Nuclear Information System (INIS)

Litvine, D.

2008-01-01

Marketing opening in the electric sector and green electricity products supply increase opportunity for households to voluntarily support renewable energy production. Despite the general development of committed actions, and in the lack of public intervention on prices, subscription rates are strongly below consumers' interest announcements and stated willingness to pay. This thesis analyses green electricity subscription factors: how to promote subscription in the case of individual sensitive and rather favourable attitude toward green electricity? Is it possible to encourage preference revelation? Answering these questions requires combining economics analysis and psychological concepts. In that aim, we employ the Theory of Planned Behavior, a social psychology model able to articulate theoretical analysis, psychological concepts and an empirical survey carried out in St Gallen (Switzerland). This survey is based on experimental method and commits, firstly, in testing our hypothesis, secondly in providing a method to influence individual beliefs in order to reinforce subscription intention. Finally, the survey is employed as an incentive tool for concretizing the intention and then promoting individual subscription. We determine that even though the premium to be paid may be an obstacle to subscription, other behavioral and attitudinal factors can explain the construction of individual preferences, intention and action. Analysing the various green electricity demand motivations as well as supply determinants enables to introduce the concept of 'certainty of subscription benefit'. The more the consciousness of personal benefit, the less price an obstacle to subscribe. As a result, our work aims firstly at providing analytical explanations to decision makers concerning the origin of the voluntary individual contribution to public goods as the environment, secondly, at developing green electricity preferences revelation mechanism. This kind of analysis is

Comparison of different diagnostic techniques for the detection of cryptosporidiosis in bovines

Directory of Open Access Journals (Sweden)

H. K. M. Rekha

2016-02-01

Full Text Available Aim: Aim of the present study was to compare different methods, viz., Sheather’s sugar flotation (SSF, Ziehl-Neelsen (ZN, Kinyoun’s acid-fast method (KAF, safranin-methylene blue staining (SMB, and negative staining techniques such as nigrosin staining, light green staining, and malachite green staining for the detection of Cryptosporidium spp. oocysts in bovines. Materials and Methods: A total of 455 fecal samples from bovines were collected from private, government farms and from the clinical cases presented to Department of Medicine, Veterinary College, Bengaluru. They were subjected for SSF, ZN, KAF, SMB and negative staining methods. Results: Out of 455 animal fecal samples screened 5.71% were found positive for Cryptosporidium spp. oocysts. The species were identified as Cryptosporidium parvum in calves and Cryptosporidium andersoni in adults based on the morphological characterization and micrometry of the oocysts. Conclusions: Of all the techniques, fecal flotation with sheather’s was found to be more specific and sensitive method for the detection of Cryptosporidium spp. oocysts. Among the conventional staining methods, the SMB gives better differentiation between oocysts and yeast. Among the three negative staining methods, malachite green was found sensitive over the other methods.

Green Transformational Leadership and Green Performance: The Mediation Effects of Green Mindfulness and Green Self-Efficacy

OpenAIRE

Yu-Shan Chen; Ching-Hsun Chang; Yu-Hsien Lin

2014-01-01

No prior literature explores the influence of green transformational leadership on green performance, thus, this study develops a novel research framework to fill the research gap. This study investigates the influence of green transformational leadership on green performance and discusses the mediation effects of green mindfulness and green self-efficacy by means of structural equation modeling (SEM). The results indicate that green transformational leadership positively influences green min...

Green competitiveness research on Chinese automotive enterprises

Directory of Open Access Journals (Sweden)

Yuanhui Li

2014-05-01

Full Text Available Purpose: More and more executives of automobileindustry in China start to recognize the concept of green competitiveness recently. However, relatively less research attention has been devoted to the consideration of measurement. This paper aims to find empirical approach to quantify green competitiveness for automotive enterprises. The connotation of green competitiveness is explored and one suite of evaluation index system has been proposed with four dimensions including environmental, resource, capability and knowledge.Design/methodology/approach: By introducing the factor analysis method, green competitiveness has been measured through an empirical analysis of 24 automotive enterprises within China.Findings: The results indicate that those elements, such as enterprise resource possession and utilization; environment, responsibility and knowledge; profitability; management efficiency, have significant effect on the green competitiveness for automotive enterprises. The further analysis also unveils the advantages and disadvantages of green competitiveness for each company and the direction for improvement.Research limitations/implications: Guide regulators and managers of automobile industry to take some measures to enhance their green competitive advantage.Practical implications: Provide practical methods to measure green competitiveness for automotive enterprises.Originality/value: This paper proposes an evaluation index system of green competitiveness for automotive enterprises. The suggestions of our research will be beneficial to enterprise executives and industry regulators.

Author Details

African Journals Online (AJOL)

Immobilization of lead in shooting range soil using biochar from spent mushroomsubstrateImmobilization of lead in shooting range soil using biochar from spent mushroomsubstrate. Abstract PDF · Vol 9, No 6S (2017) - Articles Sorption of malachite green (MG) by cassava stem biochar (CSB) kinetic and isotherm studies

Evaluation of four novel isothermal amplification assays towards simple and rapid genotyping of chloroquine resistant Plasmodium falciparum.

Science.gov (United States)

Chahar, Madhvi; Anvikar, Anup; Dixit, Rajnikant; Valecha, Neena

2018-07-01

Loop mediated isothermal amplification (LAMP) assay is sensitive, prompt, high throughput and field deployable technique for nucleic acid amplification under isothermal conditions. In this study, we have developed and optimized four different visualization methods of loop-mediated isothermal amplification (LAMP) assay to detect Pfcrt K76T mutants of P. falciparum and compared their important features for one-pot in-field applications. Even though all the four tested LAMP methods could successfully detect K76T mutants of P. falciparum, however considering the time, safety, sensitivity, cost and simplicity, the malachite green and HNB based methods were found more efficient. Among four different visual dyes uses to detect LAMP products accurately, hydroxynaphthol blue and malachite green could produce long stable color change and brightness in a close tube-based approach to prevent cross-contamination risk. Our results indicated that the LAMP offers an interesting novel and convenient best method for the rapid, sensitive, cost-effective, and fairly user friendly tool for detection of K76T mutants of P. falciparum and therefore presents an alternative to PCR-based assays. Based on our comparative analysis, better field based LAMP visualization method can be chosen easily for the monitoring of other important drug targets (Kelch13 propeller region). Copyright © 2018 Elsevier Inc. All rights reserved.

Analysis of the green certificate market

International Nuclear Information System (INIS)

Storeboe, Inger Oeydis

2001-04-01

This report studies the advantages and disadvantages of a separate financial market for the environmental advantages in the production of electricity from renewable energy sources. This market solution is evaluated against other financial systems used to promote the production of green electricity. By starting from a general equilibrium model for the green certificate market, the report discusses how the adaptation in the certificate market is influenced by changes in the market conditions. The certificate market is combined with a quota market for carbon dioxide, with and without international trade with electricity and certificate and market power in the production of electricity from renewable energy sources

LANL/Green Star spectrometer tests

International Nuclear Information System (INIS)

Sampson, T.E.; Cremers, T.L.; Vo, D.T.; Seldiakov, Y.P.; Dorin, A.B.; Kondrashov, M.V.; Timoshin, V.I.

1997-12-01

The US and Russia have agreed to the joint development of a nondestructive assay system for use to support the dismantlement of nuclear weapons in Russia. This nondestructive assay system will be used to measure plutonium produced by the conversion of Russian nuclear weapons. The NDA system for Russia will be patterned after the ARIES NDA system being constructed at Los Alamos. One goal of the program is to produce an NDA system for use in Russia that maximizes the use of Russian resources to facilitate maintenance and future upgrades. The Green Star SBS50 Single Board Spectrometer system (Green Star Ltd., Moscow, Russia) has been suggested for use as the data acquisition component for gamma ray instruments in the system. Possible uses are for plutonium isotopic analysis and also segmented gamma scanning. Green Star has also developed analysis software for the SBS50. This software, both plutonium isotopic analysis and uranium enrichment analysis, was developed specifically for customs/border inspection applications (low counting rate applications and identification as opposed to quantification) and was not intended for MC and A applications. Because of the relative immaturity of the Green Star plutonium isotopic analysis software (it has been under development for only one year and is patterned after US development circa 1980), it was tentatively agreed, before the tests, that the Russian NDA system would use the Los Alamos PC/FRAM software for plutonium isotopic analysis. However, it was also decided to include the Green Star plutonium isotopic software in the testing, both to quantify its performance for MC and A applications and also to provide additional data to Green Star for further development of their software. The main purpose of the testing was to evaluate the SBS-50 spectrometer as a data acquisition device for use with LANL software

Online marketing of green electricity in Germany—A content analysis of providers’ websites

International Nuclear Information System (INIS)

Herbes, Carsten; Ramme, Iris

2014-01-01

There is an increasing body of research on consumer preferences concerning electricity from renewable resources. The purpose of this study is to analyze how providers’ online marketing in one of the most developed markets for green energy can be improved. We conducted a content analysis of nearly 480 providers’ websites, examining as many as 620 products. We found that energy providers’ communication seems to be in line with academic research on potential customer benefits (utilitarian benefits, “warm glow”, nature experience). However, communication could be improved by giving more detailed information on the impact of the consumer's decision, e.g. by giving numbers on CO 2 -emissions saved. Moreover, providers could improve the effectiveness of their visual messages by using more pictures related to renewable energy. Further, self-expressive benefits of buying green energy could be created by offering merchandise articles symbolizing the contribution a consumer makes by choosing a green tariff. When comparing purely green energy providers to other providers, we found that the former offer a wider choice as well as more products supporting new renewable installations. Important implications for policy makers aiming to phase out alternative energy subsidies emerge from our findings. - Highlights: • We examine more than 600 product pages of green electricity providers in Germany. • We analyze providers’ product and communication policy. • Providers aptly address utilitarian and some psychological customer benefits. • Self-expressive benefits of buying green energy are not yet addressed. • Visual language and level of detail of information can be improved

Experimental analysis of green roof substrate detention characteristics.

Science.gov (United States)

Yio, Marcus H N; Stovin, Virginia; Werdin, Jörg; Vesuviano, Gianni

2013-01-01

Green roofs may make an important contribution to urban stormwater management. Rainfall-runoff models are required to evaluate green roof responses to specific rainfall inputs. The roof's hydrological response is a function of its configuration, with the substrate - or growing media - providing both retention and detention of rainfall. The objective of the research described here is to quantify the detention effects due to green roof substrates, and to propose a suitable hydrological modelling approach. Laboratory results from experimental detention tests on green roof substrates are presented. It is shown that detention increases with substrate depth and as a result of increasing substrate organic content. Model structures based on reservoir routing are evaluated, and it is found that a one-parameter reservoir routing model coupled with a parameter that describes the delay to start of runoff best fits the observed data. Preliminary findings support the hypothesis that the reservoir routing parameter values can be defined from the substrate's physical characteristics.

Factors Affecting Green Residential Building Development: Social Network Analysis

Directory of Open Access Journals (Sweden)

Xiaodong Yang

2018-05-01

Full Text Available Green residential buildings (GRBs are one of the effective practices of energy saving and emission reduction in the construction industry. However, many real estate developers in China are less willing to develop GRBs, because of the factors affecting green residential building development (GRBD. In order to promote the sustainable development of GRBs in China, this paper, based on the perspective of real estate developers, identifies the influential and critical factors affecting GRBD, using the method of social network analysis (SNA. Firstly, 14 factors affecting GRBD are determined from 64 preliminary factors of three main elements, and the framework is established. Secondly, the relationships between the 14 factors are analyzed by SNA. Finally, four critical factors for GRBD, which are on the local economy development level, development strategy and innovation orientation, developer’s acknowledgement and positioning for GRBD, and experience and ability for GRBD, are identified by the social network centrality test. The findings illustrate the key issues that affect the development of GRBs, and provide references for policy making by the government and strategy formulation by real estate developers.

Comparison of indocyanine green clearance with Child's-Pugh score and hepatic histology: a multivariate analysis.

Science.gov (United States)

Mukherjee, Sandeep; Rogers, Mary A M; Buniak, Borys

2006-01-01

Indocyanine green clearance, measured by percentage disappearance rate, detects alterations in liver function and may be used as a non-invasive determinant of hepatic reserve. The aims of this study were to compare liver histology and Child's-Pugh score with percentage disappearance rate and determine which variables correlated with PDR. Child's-Pugh score, liver function tests, liver biopsies and indocyanine green testing (0.5mg/kg) were performed in 102 consecutive patients with cirrhosis of diverse etiologies. Indocyanine green concentration was determined using spectrophotometric analysis (806nm) and plotted logarithmically with Michaelis-Menten kinetics to calculate the percentage disappearance rate. Liver biopsies were graded using the modified Knodell score to obtain a histological activity index. In bivariable analysis, percentage disappearance rate significantly correlated with Child's-Pugh score, albumin, bilirubin, prothrombin time and histological activity index. Albumin, prothrombin time and histological activity index were independent predictors of percentage disappearance rate in the final model (albumin ptime ptime and histological activity index.

Transcriptome analysis and metabolic profiling of green and red kale (Brassica oleracea var. acephala) seedlings.

Science.gov (United States)

Jeon, Jin; Kim, Jae Kwang; Kim, HyeRan; Kim, Yeon Jeong; Park, Yun Ji; Kim, Sun Ju; Kim, Changsoo; Park, Sang Un

2018-02-15

Kale (Brassica oleracea var. acephala) is a rich source of numerous health-benefiting compounds, including vitamins, glucosinolates, phenolic compounds, and carotenoids. However, the genetic resources for exploiting the phyto-nutritional traits of kales are limited. To acquire precise information on secondary metabolites in kales, we performed a comprehensive analysis of the transcriptome and metabolome of green and red kale seedlings. Kale transcriptome datasets revealed 37,149 annotated genes and several secondary metabolite biosynthetic genes. HPLC analysis revealed 14 glucosinolates, 20 anthocyanins, 3 phenylpropanoids, and 6 carotenoids in the kale seedlings that were examined. Red kale contained more glucosinolates, anthocyanins, and phenylpropanoids than green kale, whereas the carotenoid contents were much higher in green kale than in red kale. Ultimately, our data will be a valuable resource for future research on kale bio-engineering and will provide basic information to define gene-to-metabolite networks in kale. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genomic analysis of organismal complexity in the multicellular green alga Volvox carteri

Energy Technology Data Exchange (ETDEWEB)

Prochnik, Simon E.; Umen, James; Nedelcu, Aurora; Hallmann, Armin; Miller, Stephen M.; Nishii, Ichiro; Ferris, Patrick; Kuo, Alan; Mitros, Therese; Fritz-Laylin, Lillian K.; Hellsten, Uffe; Chapman, Jarrod; Simakov, Oleg; Rensing, Stefan A.; Terry, Astrid; Pangilinan, Jasmyn; Kapitonov, Vladimir; Jurka, Jerzy; Salamov, Asaf; Shapiro, Harris; Schmutz, Jeremy; Grimwood, Jane; Lindquist, Erika; Lucas, Susan; Grigoriev, Igor V.; Schmitt, Rudiger; Kirk, David; Rokhsar, Daniel S.

2010-07-01

Analysis of the Volvox carteri genome reveals that this green alga's increased organismal complexity and multicellularity are associated with modifications in protein families shared with its unicellular ancestor, and not with large-scale innovations in protein coding capacity. The multicellular green alga Volvox carteri and its morphologically diverse close relatives (the volvocine algae) are uniquely suited for investigating the evolution of multicellularity and development. We sequenced the 138 Mb genome of V. carteri and compared its {approx}14,500 predicted proteins to those of its unicellular relative, Chlamydomonas reinhardtii. Despite fundamental differences in organismal complexity and life history, the two species have similar protein-coding potentials, and few species-specific protein-coding gene predictions. Interestingly, volvocine algal-specific proteins are enriched in Volvox, including those associated with an expanded and highly compartmentalized extracellular matrix. Our analysis shows that increases in organismal complexity can be associated with modifications of lineage-specific proteins rather than large-scale invention of protein-coding capacity.

Adsorptive Removal of Malachite Green with Activated Carbon ...

African Journals Online (AJOL)

NICO

2012-11-22

Nov 22, 2012 ... The kinetics of the adsorption process was tested by means of pseudo-first-order, pseudo-second-order and ... the production of activated carbon by using agricultural ... tion Number 42 000, with the chemical formula C52H54N4O12, and ...... 40 S. Lagergren and B. K. Svenska, Band., 1893, 24, 1–13.

Adsorptive Removal of Malachite Green with Activated Carbon ...

African Journals Online (AJOL)

NICO

2012-11-22

Nov 22, 2012 ... pyrolyzed in a stainless steel vertical tubular reactor placed in a tube furnace under ... the gas flow was switched to CO2 and activation was continued for 2 h. ... where Co and Ce (mg L–1) are the initial and equilibrium liquid- .... increase in contact time did not enhance the MG dye adsorption process.

GREEN PACKAGING, GREEN PRODUCT, GREEN ADVERTISING, PERSEPSI, DAN MINAT BELI KONSUMEN

OpenAIRE

Imam Santoso; Rengganis Fitriani

2016-01-01

Environmental problems become one of the strategic issues in achieving global competitiveness. One of the issues is products that are made from environmental friendly materials or known as green product. Furthermore, in green products marketing, the company also uses green packaging and green advertising concept. This study aimed to analyze the effect of green packaging, green products, and green advertising on consumer perception and purchasing intention. The study was conducted in Ketawangg...

WHERE IS THE VALUE IN GREENING YOUR BRAND? AN ANALYSIS OF THE CANADIAN HOTEL INDUSTRY

OpenAIRE

Bedlington, Emma

2009-01-01

This paper assesses the potential for a green hotel brand in the Canadian market, given the current industry trend towards environmentally friendly operations. To begin, an industry analysis of the competitive landscape is performed with a focus on the luxury hotel segment. A discussion of the key players in the Canadian market provides further context. The paper continues by analyzing the consumer decision process within the hotel industry, in conjunction with green consumer behaviour. Final...

Influence of the preparation method on the structure, optical and photocatalytic properties of nanosized ZnO

Energy Technology Data Exchange (ETDEWEB)

Gancheva, M., E-mail: mancheva@svr.igic.bas.bg [Institute of General and Inorganic Chemistry, Bulgarian Academy of Science, Acad. G. Bonchev Str., bl.11, 1113, Sofia (Bulgaria); Uzunov, I.; Iordanova, R. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Science, Acad. G. Bonchev Str., bl.11, 1113, Sofia (Bulgaria); Papazova, K. [University of Sofia, Faculty of Chemistry and Pharmacy, James Bourchier 1 Blvd., 1164, Sofia (Bulgaria)

2015-08-15

Mechanochemical activation is the most commonly applied approach for improving the photocatalytic properties of commercial zinc oxide. Here we show that ZnO obtained by two-pathway decomposition of basic zinc carbonate also possesses a very good photocatalytic activity. Nanosized ZnO powders were successfully prepared by thermal and mechanochemical decomposition of Zn{sub 5}(CO{sub 3}){sub 2}(OH){sub 6}, precipitated under soft conditions. The precursor and final products were characterized by X-ray diffraction (XRD), thermal analysis (TG/DTA), infrared spectroscopy (IR) and B.E.T method. The morphology of the ZnO was observed by SEM analysis. The optical and photocatalytic properties of the prepared zinc oxides were also investigated and compared with commercial ZnO. The band gaps of the thermal and mechanochemical obtained ZnO nanopowders are 3.22 and 3.04 eV, respectively. The degree of decomposition of Malachite Green under UV and visible irradiations in the presence of ZnO prepared by both methods reached levels above 90%. Better catalytic activity was found for the visible region. It was established that the process follows second order kinetics. - Graphical abstract: Display Omitted - Highlights: • Synthesis of nanosized ZnO from hydrozincite by thermal and mechanochemical route. • ZnO powders possess high photocatalytic activity under UV and visible irradiation. • The degree of decomposition of Malachite Green is more than 90% for the both ZnO's. • The photodecomposition of MG under UV/Vis irradiation follows second order kinetics.

Greens of the European Green Capitals

Science.gov (United States)

Cömertler, Seval

2017-10-01

Well established and maintained green areas have a key role on reaching the high quality of life and sustainability in urban environments. Therefore, green areas must be carefully accounted and evaluated in the urban planning affairs. In this context, the European Green Capitals, which attach a great importance to the green areas, have a great potential to act as a role model for both small and big cities in all around the world. These leading cities (chronologically, Stockholm, Hamburg, Vitoria-Gasteiz, Nantes, Copenhagen, Bristol, Ljubljana, Essen and Nijmegen) are inspiring for the other cities which seek to achieve more sustainable and environmentally friendly places through green areas. From this point of view, the aim of this paper was to investigate the green areas of the European Green Capitals. The paper covered whole European Green Capitals, and the application form of each Green Capital was used as a primary data source. Consequently, the paper put forwarded that the European Green Capitals have considerably large amount and high proportion of green areas. Further, these cities provide an excellent access to the public green areas. As a result of abundant provision and proper distribution, the almost all citizens in most of the Green Capitals live within a distance of 300 meters to a green area. For further researches, the paper suggested that these green capitals should be investigated in terms of their efforts, measures, goals and plans, policies and implications to administer, to protect, to enhance and to expand the green areas.

Refinement of the crystal structure of malachite, Cu/sub 2/(OH)/sub 2/CO/sub 3/, by neutron diffraction

Energy Technology Data Exchange (ETDEWEB)

Zigan, F; Joswig, W; Schuster, H D [Frankfurt Univ. (Germany, F.R.); Mason, S A [Institut Max von Laue - Paul Langevin, 38 - Grenoble (France)

1977-01-01

The crystal structure of malachite is refined (R = 0,021) with the intensity values of 635 independent neutron reflexions from a single crystal, rather free from absorption and extinction. Concerning the structural geometry, no essential deviations occur from the known results of x-ray diffraction. The thermal elongations are generally largest about the normal to the (201) layers, between which the bonding is relatively weak. In both of the (medium, bent) OH...O hydrogen bonds, the anisotropic thermal parameters, converted according to the riding model, are - with certain restrictions - in agreement with the measured infrared spectrum as well as with frequencies and directions of the proton vibration calculated from the bonding geometry on the basis of a theoretical model.

Energy prices, technological knowledge and green energy innovation. A dynamic panel analysis of patent counts

International Nuclear Information System (INIS)

Kruse, Juergen; Wetzel, Heike; Koeln Univ.

2014-01-01

We examine the effect of energy prices and technological knowledge on innovation in green energy technologies. In doing so, we consider both demand-pull effects, which induce innovative activity by increasing the expected value of innovations, and technology-push effects, which drive innovative activity by extending the technological capability of an economy. Our analysis is conducted using patent data from the European Patent Office on a panel of 26 OECD countries over the period 1978-2009. Utilizing a dynamic count data model for panel data, we analyze 11 distinct green energy technologies. Our results indicate that the existing knowledge stock is a significant driver of green energy innovation for all technologies. Furthermore, the results suggest that energy prices have a positive impact on innovation for some but not all technologies and that the e.ect of energy prices and technological knowledge on green energy innovation becomes more pronounced after the Kyoto protocol agreement in 1997.

Gum karaya based hydrogel nanocomposites for the effective removal of cationic dyes from aqueous solutions

CSIR Research Space (South Africa)

Mittala, H

2016-02-01

Full Text Available after nanocomposite formation with SiC NPs. The HNC was employed for the removal of cationic dyes, i.e., malachite green (MG) and rhodamine B (RhB) from the aqueous solution. The HNC was found to remove 91% (MG) and 86% (RhB) of dyes with a polymer dose...

Ultra-fast science at the CSIR:NLC

CSIR Research Space (South Africa)

Botha, L

2008-05-01

Full Text Available by focussing femtosecond pulse onto sapphire plate acts as a probe • Measured on spectrometer • Example: Malachite green 0 2000 4000 6000 8000 550 600 650 700 Delay [fs] W a v e l e n g t h [ n m ] 0 2000 4000 6000 8000 -0.05 -0...

Bulletin of Materials Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The refinement of 28 instrumental and structural parameters led to R p = 8.1 %, R ... Optimization of CVD parameters for long ZnO NWs grown on ITO/glass substrate ..... Photocatalytic degradation of Malachite Green dye by modified ZnO nanomaterial ...... Loss of outer membrane integrity in Gram-negative bacteria by silver ...

Remediation of azo dyes by using household used black tea as an ...

African Journals Online (AJOL)

In the present study used black tea and its impregnates were used as an adsorbents for the removal of textile dyes such as methylene blue and malachite green. The impregnation technique was adopted for the preparation of metal impregnates. The present study shows that used black tea and its impregnate exhibit ...

Browse Title Index

African Journals Online (AJOL)

Issue, Title. Vol 22, No 2 (2008), Voltammetric determination of heparin based on its interaction with malachite green, Abstract PDF. Xueliang Niu, Weili Zhang, Na Zhao, Wei Sun. Vol 22, No 2 (2008), Voltammetric determination of l-cysteic acid on a 1-[4-(ferrocenyl-ethynyl)phenyl]-1-ethanone modified carbon paste ...

Mapping Green Spaces in Bishkek—How Reliable can Spatial Analysis Be?

Directory of Open Access Journals (Sweden)

Peter Hofmann

2011-05-01

Full Text Available Within urban areas, green spaces play a critically important role in the quality of life. They have remarkable impact on the local microclimate and the regional climate of the city. Quantifying the ‘greenness’ of urban areas allows comparing urban areas at several levels, as well as monitoring the evolution of green spaces in urban areas, thus serving as a tool for urban and developmental planning. Different categories of vegetation have different impacts on recreation potential and microclimate, as well as on the individual perception of green spaces. However, when quantifying the ‘greenness’ of urban areas the reliability of the underlying information is important in order to qualify analysis results. The reliability of geo-information derived from remote sensing data is usually assessed by ground truth validation or by comparison with other reference data. When applying methods of object based image analysis (OBIA and fuzzy classification, the degrees of fuzzy membership per object in general describe to what degree an object fits (prototypical class descriptions. Thus, analyzing the fuzzy membership degrees can contribute to the estimation of reliability and stability of classification results, even when no reference data are available. This paper presents an object based method using fuzzy class assignments to outline and classify three different classes of vegetation from GeoEye imagery. The classification result, its reliability and stability are evaluated using the reference-free parameters Best Classification Result and Classification Stability as introduced by Benz et al. in 2004 and implemented in the software package eCognition (www.ecognition.com. To demonstrate the application potentials of results a scenario for quantifying urban ‘greenness’ is presented.

Green Building Implementation at Schools in North Sulawesi, Indonesia

Science.gov (United States)

Harimu, D. A. J.; Tumanduk, M. S. S. S.

2018-02-01

This research aims at investigating the green building implementation at schools in North Sulawesi, Indonesia; and to analysis the relationship between implementation of green building concept at school with students’ green behaviour. This research is Survey Research with quantitative descriptive method. The analysis unit is taken purposively, that is school that had been implemented the green building concept, Manado’s 3rd Public Vocational High School, Lokon High School at Tomohon, Manado Independent School at North Minahasa, and Tondano’s 3rd Public Vocational High School. Data collecting is acquired by observation and questionnaire. The Assessment Criteria of green building on Analysis Unit, is taken from Greenship Existing Building ver 1. There are 4 main points that being assessed, which are Energy Conservation and Efficiency; Water Conservation; Indoor Health and Comfort; Waste Managerial. The Analysis technique used in this research is the simple regression analysis. The result of the research shows that there is a significant relation between green building implementation at school and students’ green behavior. The result is accordance with the Gesalts Psychologist theories, that architecture can change the user’s behaviour.

From green architecture to architectural green

DEFF Research Database (Denmark)

Earon, Ofri

2011-01-01

that describes the architectural exclusivity of this particular architecture genre. The adjective green expresses architectural qualities differentiating green architecture from none-green architecture. Currently, adding trees and vegetation to the building’s facade is the main architectural characteristics...... they have overshadowed the architectural potential of green architecture. The paper questions how a green space should perform, look like and function. Two examples are chosen to demonstrate thorough integrations between green and space. The examples are public buildings categorized as pavilions. One......The paper investigates the topic of green architecture from an architectural point of view and not an energy point of view. The purpose of the paper is to establish a debate about the architectural language and spatial characteristics of green architecture. In this light, green becomes an adjective...

Green businesses in a clean energy economy: Analyzing drivers of green business growth in U.S. states

International Nuclear Information System (INIS)

Yi, Hongtao

2014-01-01

In a clean energy economy, green businesses play a central role by utilizing renewable energy technologies and employing green labor forces to provide clean energy services and goods. This paper aims at analyzing factors driving the growth and survival of green businesses in the U.S. states, with hypotheses proposed on the impacts from clean energy policies and tax incentives, labor market conditions, and economic and political environments. A fixed effect regression analysis is applied with a panel data set of 48 continental states from 1998 to 2007 in the United States. The statistical analysis with a longitudinal data set reveals that the adoption of renewable energy policies, the permission of renewable energy credits imports, the stringency of minimum wage legislations, and presence of clean energy business associations are the major driving forces of the green business development in the U.S. states. - Highlights: • This paper studies the growth of green businesses in the U.S. states. • The adoption of RPS (Renewable Portfolio Standard) is positively associated with number of green businesses. • Clean energy NGOs are positively associated with green business growth

Analysis The Effect Of Enviromental Concern And Green Advertising To Green Purchasing In Palembang City

Directory of Open Access Journals (Sweden)

Zakaria Wahab

2017-12-01

Full Text Available This study aims to determine the effect of environmental concern and green advertising to consumer behavior in purchasing green products (environmentally friendly bag. The study was conducted by distributing questionnaires to 200 respondents which already have purchase and know about new government regulations that require to buy a plastic bag that used in large retail. This study conducted in some major retail in Palembang (Hypermart, Diamond, and Carrefour. This study uses Structural Equation Modeling (SEM with AMOS program to analyze the data. The results showed that green advertising significantly influence behavior change and environmental concerns significantly influence purchase decisions with the effect of changes in consumer behavior on purchasing decisions by 74.0 % and the balance of 26.0 % is the influence of other factors not examined in this research.

The Influence of Proactive Green Innovation and Reactive Green Innovation on Green Product Development Performance: The Mediation Role of Green Creativity

Directory of Open Access Journals (Sweden)

Yu-Shan Chen

2016-09-01

Full Text Available This study fills the research gap in the exploration of the relationships between both proactive and reactive green innovations and green product development performance, and examines the mediating effect of green creativity. Structural equation modeling (SEM is utilized to test the hypotheses. From the sample of 146 valid respondents, the results show that proactive green innovation positively affects green creativity and green product development performance, and green creativity positively affects green product development performance. In addition, our findings also indicate that the relationship between proactive green innovation and green product development performance is partially mediated by green creativity. Accordingly, green creativity plays a critical role for companies to achieve a great green product development performance. However, reactive green innovation does not significantly influence green creativity and green product development performance. Companies should develop proactive green innovation rather than reactive green innovation in order to enhance their green creativity and increase their product development performance.

[Optimization of urban green space spatial arrangement based on supply-demand analysis: a case study in Nanjing City, China].

Science.gov (United States)

Gui, Kun-Peng; Xu, Jian-Gang; Zhang, Xiang

2013-05-01

Urban green space has the functions of ecological and social services, and the two services levels are decided by the supply-demand relationship. However, the supply-demand of green space not only involves in quantity, but also refers to spatial distribution. Therefore, only greening indicators can not wholly reflect the true levels of green space services. Based on the supply-demand analysis and supported by the ArcGIS, this paper examined the ecological and social services levels of the urban green spaces in Nanjing City by using the evenness indicator and the rate the people could enjoy the public green space in their accessible area. Accordingly, the ecological and social services levels of the green space in the City were investigated. The results showed that in the east of Nanjing City, green spaces were rich, but high accessible ones were lack, which resulted in a moderate social service level. In the center of the City, green spaces were lack and distributed unevenly, resulting in the low levels of ecological and social services. In Hexi area, due to the shortage in ecological green space and its uneven distribution, the green spaces had a high level social service but a low level ecological service. In the southern and northern areas of the City, green spaces were in deficiency, uneven distribution, and lack in high accessible.

Market analysis green electricity. Final report; Marktanalyse Oekostrom. Endbericht

Energy Technology Data Exchange (ETDEWEB)

Reichmuth, Matthias [Leipziger Institut fuer Energie GmbH, Leipzig (Germany)

2014-03-15

In the present study the volume of the German market for green energy will be analyzed for its functionality, barriers and also its development perspectives. Besides an evaluation of actual literature sources, elaborate interviews of electricity suppliers (green energy suppliers) were realized.

Empirical Analysis of Green Supply Chain Management Practices in Indian Automobile Industry

Science.gov (United States)

Luthra, S.; Garg, D.; Haleem, A.

2014-04-01

Environmental sustainability and green environmental issues have an increasing popularity among researchers and supply chain practitioners. An attempt has been made to identify and empirically analyze green supply chain management (GSCM) practices in Indian automobile industry. Six main GSCM practices (having 37 sub practices) and four expected performance outcomes (having 16 performances) have been identified by implementing GSCM practices from literature review. Questionnaire based survey has been made to validate these practices and performance outcomes. 123 complete questionnaires were collected from Indian automobile organizations and used for empirical analysis of GSCM practices in Indian automobile industry. Descriptive statistics have been used to know current implementation status of GSCM practices in Indian automobile industry and multiple regression analysis has been carried out to know the impact on expected organizational performance outcomes by current GSCM practices adopted by Indian automobile industry. The results of study suggested that environmental, economic, social and operational performances improve with the implementation of GSCM practices. This paper may play an important role to understand various GSCM implementation issues and help practicing managers to improve their performances in the supply chain.

Pengaruh Green Marketing Hotel Terhadap Green Consumer Behavior

OpenAIRE

Yo Fernandez, Eunike Christe; Tjoanda, Evelyn

2017-01-01

Penelitian ini dilakukan untuk mengetahui pengaruh dari green marketing hotel terhadap green consumer behavior. Green marketing memiliki 3 dimensi, yaitu green product, green price, dan green promotion. Penelitian ini melibatkan 272 responden masyarakat Surabaya dan menggunakan metode regresi linear berganda. Hasil penelitian menunjukkan bahwa green product dan green price berpengaruh secara positif dan signifikan sedangkan green promotion berpengaruh namun tidak signifikan terhadap green con...

Extraction-spectrophotometric method for silicon determination in high-purity substances. 1. Silicon determination in tellurium

Energy Technology Data Exchange (ETDEWEB)

Shaburova, V P; Yudelevich, I G [AN SSSR, Novosibirsk (USSR). Inst. Neorganicheskoj Khimii

1989-01-01

The extraction-spectrophotometric method for silicon determination in tellurium based on extraction isolation of the base by tributyl phosphate from hydrochloride solutions and with addition of HNO/sub 3/ and spectrophotometric silicon determination using malachite green is developed. The method permits to determine 2x10/sup -1/-3x10/sup -4/ % Si.

E S Kunarti

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. E S Kunarti. Articles written in Bulletin of Materials Science. Volume 37 Issue 6 October 2014 pp 1419-1426. Wash fastness improvement of malachite green-dyed cotton fabrics coated with nanosol composites of silica–titania · I Kartini I Ilmi E S Kunarti Kamariah · More Details ...

Analysis the Effect of Enviromental Concern and Green Advertising to Green Purchasing in Palembang City

OpenAIRE

Wahab, Zakaria; Tama, Rio Adistia; Shihab, Muchsin Saggaf; Widad, Achmad; Nofiawaty, Nofiawaty; Diah, Yuliansyah M

2017-01-01

This study aims to determine the effect of environmental concern and green advertising to consumer behavior in purchasing green products (environmentally friendly bag). The study was conducted by distributing questionnaires to 200 respondents which already have purchase and know about new government regulations that require to buy a plastic bag that used in large retail. This study conducted in some major retail in Palembang (Hypermart, Diamond, and Carrefour). This study uses Structural Equa...

(TECTONA GRANDIS LEAF POWDER

Directory of Open Access Journals (Sweden)

Yash Mishra

2015-01-01

Full Text Available In this study, the adsorption potential of Teak (Tectona grandis leaf powder (TLP toremove Methylene blue (MB and Malachite Green (MG dye molecules from aqueoussolution was investigated. Batch experiments were conducted to evaluate the influenceof operational parameters such as, pH (2−9, adsorbent dosage (1−7 g/L, contact time(15−150 minutes and initial dye concentration (20−120 mg/L at stirring speed of 150rpm for the adsorption of MB and MG on TLP. Maximum removal efficiency of 98.4%and 95.1% was achieved for MB and MG dye, respectively. The experimentalequilibrium data were analysed using Langmuir, Freundlich and Temkin isothermmodels and it was found that, it fitted well to the Freundlich isotherm model. Thesurface structure and morphology of the adsorbent was characterized using scanningelectron microscopy (SEM and the presence of functional groups and its interactionwith the dye molecules were analysed using Fourier transform infrared spectroscopy(FTIR. Based on the investigation, it has been demonstrated that the teak leaf powderhas good potential for effective adsorption of methylene blue and malachite green dye.

Adsorption of hazardous cationic dye onto the combustion derived SrTiO3 nanoparticles: Kinetic and isotherm studies

Directory of Open Access Journals (Sweden)

N.P. Bhagya

2016-03-01

Full Text Available In this article we report on solution combustion method to synthesize SrTiO3 nanoparticles (ST-NPs and the removal of malachite green (MG azo dye from the aqueous solution. The synthesized ST-NPs were calcined at 600 °C for 2 h. Powder X-ray diffraction (PXRD, field emission scanning electron microscopy (FE-SEM, transmission electron microscopy (TEM, Fourier transform infrared spectroscopy (FT-IR, and Brunauer–Emmett–Teller (BET were used to characterize the product. Adsorption experiments were performed with cationic malachite green (MG dye. ∼98% dye was adsorbed onto the ST-NPs at pH 10 for 30 min of the contact time. The optimum adsorbent dose was found to be 0.015 g/L of the dye. To study the adsorption kinetics Langmuir Hinshelwood model was used and the first order kinetic best describes the MG adsorption onto the ST-NPs. The adsorption isotherms data of MG onto ST-NPs obtained were analyzed by Langmuir and Freundlich isotherm models and the results describe the best representation of the Langmuir isotherm model.

Utilization of a new optical sensor unit to monitor the electrochemical elimination of selected dyes in water

Science.gov (United States)

Valica, M.; Černá, T.; Hostin, S.

2017-10-01

This paper presents results obtained by developed optical sensor, which consist from multi-wavelength LED light source and two photodetectors capable of measuring the change in optical signal along two different optical paths (absorbance and reflectance measurements). Arduino microcomputer was used for light source management and optical signal data measuring and recording. Analytical validation of developed optical sensor is presented in this paper. The performance of the system has been tested with varying water solution of dyes (malachite green, methyl orange, trypan red). These results show strong correlations between the optical signal response and colour change from the dyes. Sensor was used for continual in-situ monitoring of electrochemical elimination of selected dyes (current density 15.7 mA cm-2, electrolyte volume 4 L and NaCl concentration 2 g L-1). Maximum decolorization level varies with each dye. For malachite green was obtain 92,7 % decolorization (25 min); methyl orange 90,8% (8,5 min) and trypan red 84,7% decolorization after 33 min of electrochemical treatment.

A Comparative Analysis of Policy Instruments Promoting Green Electricity under Uncertainty

International Nuclear Information System (INIS)

Carlen, Bjoern

2006-07-01

The paper presented here studies, in a more systematic way than previous literature, the implications uncertainty regarding i.a. future production costs of green as well as conventional electricity has on the optimal choice of instrument to promote production of green electricity. The objective is to identify relevant effects the regulator need to assess before being able to make an informed choice. The instruments studied are (i) a feed-in tariff, i.e., an obligation for retailers of electricity to buy whatever quantity of green electricity that is supplied at a price determined by the regulator, (ii) a so-called environmebonus; , i.e., a fixed premium to producers of green electricity over and above the market price on electricity, (iii) an obligation for the retailers to procure a certain quantity of green electricity, and (iv) green electricity certificates, i.e., an obligation for retailers to purchase green electricity in an amount equal to a given share of their total electricity sale. It has been suggested, in the literature on instruments to promote production of green electricity, that price-based policies (e.g., fixed-in tariffs) would be superior to quantity-based policies (e.g., an obligation on retailers of electricity to procure a given amount of green electricity). The stated reason is that quantity-based policies tend to induce too much (little) green electricity whenever production costs turn out to be higher (lower) than expected. However, price-based policies, on the other hand, induces too little (much) green electricity, and, as shown here quantity-based policies can be designed in ways making them superior to a fixed feed-in tariff in the sense of yielding a smaller expected efficiency loss. It is also shown here that green electricity certificate system and systems with so-called environmental bonuses are more complicated policy instruments than so far has been recognized. If future electricity prices are highly uncertain, an environmental

An environmental cost-benefit analysis of alternative green roofing strategies

Science.gov (United States)

Richardson, M.; William, R. K.; Goodwell, A. E.; Le, P. V.; Kumar, P.; Stillwell, A. S.

2016-12-01

Green roofs and cool roofs are alternative roofing strategies that mitigate urban heat island effects and improve building energy performance. Green roofs consist of soil and vegetation layers that provide runoff reduction, thermal insulation, and potential natural habitat, but can require regular maintenance. Cool roofs involve a reflective layer that reflects more sunlight than traditional roofing materials, but require additional insulation during winter months. This study evaluates several roofing strategies in terms of energy performance, urban heat island mitigation, water consumption, and economic cost. We use MLCan, a multi-layer canopy model, to simulate irrigated and non-irrigated green roof cases with shallow and deep soil depths during the spring and early summer of 2012, a drought period in central Illinois. Due to the dry conditions studied, periodic irrigation is implemented in the model to evaluate its effect on evapotranspiration. We simulate traditional and cool roof scenarios by altering surface albedo and omitting vegetation and soil layers. We find that both green roofs and cool roofs significantly reduce surface temperature compared to the traditional roof simulation. Cool roof temperatures always remain below air temperature and, similar to traditional roofs, require low maintenance. Green roofs remain close to air temperature and also provide thermal insulation, runoff reduction, and carbon uptake, but might require irrigation during dry periods. Due to the longer lifetime of a green roof compared to cool and traditional roofs, we find that green roofs realize the highest long term cost savings under simulated conditions. However, using longer-life traditional roof materials (which have a higher upfront cost) can help decrease this price differential, making cool roofs the most affordable option due to the higher maintenance costs associated with green roofs

Green(ing) infrastructure

CSIR Research Space (South Africa)

Van Wyk, Llewellyn V

2014-03-01

Full Text Available the generation of electricity from renewable sources such as wind, water and solar. Grey infrastructure – In the context of storm water management, grey infrastructure can be thought of as the hard, engineered systems to capture and convey runoff..., pumps, and treatment plants.  Green infrastructure reduces energy demand by reducing the need to collect and transport storm water to a suitable discharge location. In addition, green infrastructure such as green roofs, street trees and increased...

Cost-Benefit Analysis of Green Infrastructures on Community Stormwater Reduction and Utilization: A Case of Beijing, China.

Science.gov (United States)

Liu, Wen; Chen, Weiping; Feng, Qi; Peng, Chi; Kang, Peng

2016-12-01

Cost-benefit analysis is demanded for guiding the plan, design and construction of green infrastructure practices in rapidly urbanized regions. We developed a framework to calculate the costs and benefits of different green infrastructures on stormwater reduction and utilization. A typical community of 54,783 m 2 in Beijing was selected for case study. For the four designed green infrastructure scenarios (green space depression, porous brick pavement, storage pond, and their combination), the average annual costs of green infrastructure facilities are ranged from 40.54 to 110.31 thousand yuan, and the average of the cost per m 3 stormwater reduction and utilization is 4.61 yuan. The total average annual benefits of stormwater reduction and utilization by green infrastructures of the community are ranged from 63.24 to 250.15 thousand yuan, and the benefit per m 3 stormwater reduction and utilization is ranged from 5.78 to 11.14 yuan. The average ratio of average annual benefit to cost of four green infrastructure facilities is 1.91. The integrated facilities had the highest economic feasibility with a benefit to cost ratio of 2.27, and followed by the storage pond construction with a benefit to cost ratio of 2.14. The results suggested that while the stormwater reduction and utilization by green infrastructures had higher construction and maintenance costs, their comprehensive benefits including source water replacements benefits, environmental benefits and avoided cost benefits are potentially interesting. The green infrastructure practices should be promoted for sustainable management of urban stormwater.

Analisis Pengaruh Green Product dan Green Advertising terhadap Keterlibatan Konsumen dan Dampaknya pada Keputusan Pembelian Konsumen Laksmie Florist

Directory of Open Access Journals (Sweden)

Tinjung Desy Nursanti

2011-11-01

Full Text Available Marketing-oriented concept of community not only relies on community needs, but also can bring prosperity through environmental responsibility around; in this case the product and the marketing are more environmentally friendly. Application of green products and green advertising might attract widespread public sympathy, and even requirements for operational permits, production and ease of obtaining bank credit facility or tax relief may be considered by the government that is now more incentive to campaign for the concept and implementation of policies and regulations of corporate social responsibility. The objectives of this study was to determine whether there is influence of green product and green advertising toward consumer involvement and also its impact on consumer purchasing decisions Laksmi florist company. A survey with analysis of individual consumer of Lakmi florist is conducted, while path analysis is used to determine the effect among variables. The results showed that green advertising as well as green product provide a positive and significant influence on consumer involvement that have an impact on consumer purchasing decisions of Laksmi Florist company. 

[Scale effect of Nanjing urban green infrastructure network pattern and connectivity analysis.

Science.gov (United States)

Yu, Ya Ping; Yin, Hai Wei; Kong, Fan Hua; Wang, Jing Jing; Xu, Wen Bin

2016-07-01

Based on ArcGIS, Erdas, GuidosToolbox, Conefor and other software platforms, using morphological spatial pattern analysis (MSPA) and landscape connectivity analysis methods, this paper quantitatively analysed the scale effect, edge effect and distance effect of the Nanjing urban green infrastructure network pattern in 2013 by setting different pixel sizes (P) and edge widths in MSPA analysis, and setting different dispersal distance thresholds in landscape connectivity analysis. The results showed that the type of landscape acquired based on the MSPA had a clear scale effect and edge effect, and scale effects only slightly affected landscape types, whereas edge effects were more obvious. Different dispersal distances had a great impact on the landscape connectivity, 2 km or 2.5 km dispersal distance was a critical threshold for Nanjing. When selecting the pixel size 30 m of the input data and the edge wide 30 m used in the morphological model, we could get more detailed landscape information of Nanjing UGI network. Based on MSPA and landscape connectivity, analysis of the scale effect, edge effect, and distance effect on the landscape types of the urban green infrastructure (UGI) network was helpful for selecting the appropriate size, edge width, and dispersal distance when developing these networks, and for better understanding the spatial pattern of UGI networks and the effects of scale and distance on the ecology of a UGI network. This would facilitate a more scientifically valid set of design parameters for UGI network spatiotemporal pattern analysis. The results of this study provided an important reference for Nanjing UGI networks and a basis for the analysis of the spatial and temporal patterns of medium-scale UGI landscape networks in other regions.

A Fuzzy MCDM Approach to Evaluate Green Suppliers

Directory of Open Access Journals (Sweden)

Gizem Cifci

2011-10-01

Full Text Available Nowadays the effect of industrial production on the environment brought out the importance of the green concept in supply chains. Particularly for supplier firms, greening is essential in a supply chain because with growing worldwide awareness of environmental protection, green production has become an important theme for almost every manufacturer. While literature related to supplier evaluation is plentiful, the works on green supplier evaluation are rather limited. Therefore, a green supplier evaluation model is proposed in this study. Due to its multi-criteria nature, the green supplier evaluation process requires an appropriate multi criteria analysis and solution approach. Selecting a proper method involves an insight analysis among available multi-criteria decision making (MCDM techniques. Among numerous methods of MCDM, this paper presents a decision framework based on group decision making (GDM and fuzzy analytic hierarchy process (FAHP for evaluating and selecting green suppliers. The applicability of the proposed approach is verified through a case study.

Perspectives of development of green jobs in Bulgaria

Directory of Open Access Journals (Sweden)

Stoyanova Zornitsa

2015-01-01

Full Text Available The transformation to green sectors of the economy in Bulgaria leads after it the need of new type of professions, which would be capable to cope with the new conditions and requirements which different businesses are facing. The knowledge of creation of green jobs in Bulgaria is insufficient, which makes this paper state of art. Green jobs in Bulgaria are connected with transfer of business activities to green ones. The paper analyzes and evaluates the current conditions of creation of green jobs in Bulgaria. It is proposed analysis of the requirements in Bulgaria about the eligible criteria to apply for funding under the measurement of green jobs; based on research SWOT analysis of creation of green jobs. The results are systematized in findings, conclusions and policy recommendations, as changing conditions of applying to measurement, payment connected to employees, and etc. As well is proposed cooperation between other existing measurements for reaching sustainable employment in Bulgaria.

Toronto green roof construction standard

International Nuclear Information System (INIS)

Aster, D.

2007-01-01

Toronto City Council adopted a green roof strategy in February 2006. This paper reviewed the by-law governing the strategy as well as the work in progress to develop minimum standards for the design and construction of green roofs in Toronto. The strategy included a series of recommendations regarding the installation of green roofs on city buildings; a pilot grant program; using the development process to encourage green roofs; and, public education and promotion. It was noted that compared to Europe, the development of standards for green roofs in North America is in its early stages. As an emerging sustainable technology, there currently are no standards incorporated into Ontario's Building Code against which Toronto can measure the design and construction of green roofs. Therefore this paper included an analysis detailing how the recommended design requirements were able to support the City's green roof policy objectives and integrate the performance criteria for green roofs previously established and supported by Toronto City Council. The key policy objectives of the City's green roof strategy were to reduce the urban heat island effect; to address stormwater management implications in terms of quality and quantity; to improve the energy budgets of individual buildings; and, to improve air quality

Financial analysis of community-based forest enterprises with the Green Value tool

Science.gov (United States)

S. Humphries; Tom Holmes

2016-01-01

The Green Value tool was developed in response to the need for simplified procedures that could be used in the field to conduct financial analysis for community-based forest enterprises (CFEs). Initially our efforts focused on a set of worksheets that could be used by both researchers and CFEs to monitor and analyze costs and income for one production period. The...

Certification Systems of Green Schools: A Comparative Analysis

Directory of Open Access Journals (Sweden)

Ibrahim Kocabas

2017-12-01

Full Text Available Sustainability is an approach that should not merely be limited to the design of buildings, but be a lifestyle adopted by posterity. Individuals ought to have the consciousness to protect and preserve the natural resources of future generations. After all, this is what will probably make studies on sustainability reach their targets. School buildings are critically important in achieving this goal in that they can enable future generations to be raised with an awareness of sustainability. This explains the reason why, in this study, the following leading green school certification systems and their criteria have been compared and examined: Leadership in Energy and Environmental Design; Collaborative for High Performance Schools; and, Building Research Establishment Environmental Assessment Method. Five schools with these certificates were taken as examples, evaluated and compared. This study, in which descriptive survey model was employed, made it clear that the standards set for green schools serve similar purposes no matter when a green school certification system originated or which countries have adopted it. However, the following variables play an important role in the success of the green school approach: attitudes of administrators; training pattern; location of the school; materials selection; and the responsibilities of educators and learners. School buildings in Turkey should further be discussed in detail with these points in mind.

Dynamics of Hierarchical Urban Green Space Patches and Implications for Management Policy.