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Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

Rani,Babita; Kumar,Vivek; Singh,Jagvijay; Bisht,Sandeep; Teotia,Priyanku; Sharma,Shivesh; Kela,Ritu
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
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15.87%
Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination.

Biochemical evolution II: Origin of life in tubular microstructures on weathered feldspar surfaces

Parsons, Ian; Lee, Martin R.; Smith, Joseph V.
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: Artigo de Revista Científica
Publicado em 22/12/1998 EN
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Mineral surfaces were important during the emergence of life on Earth because the assembly of the necessary complex biomolecules by random collisions in dilute aqueous solutions is implausible. Most silicate mineral surfaces are hydrophilic and organophobic and unsuitable for catalytic reactions, but some silica-rich surfaces of partly dealuminated feldspars and zeolites are organophilic and potentially catalytic. Weathered alkali feldspar crystals from granitic rocks at Shap, north west England, contain abundant tubular etch pits, typically 0.4–0.6 μm wide, forming an orthogonal honeycomb network in a surface zone 50 μm thick, with 2–3 × 106 intersections per mm2 of crystal surface. Surviving metamorphic rocks demonstrate that granites and acidic surface water were present on the Earth’s surface by ∼3.8 Ga. By analogy with Shap granite, honeycombed feldspar has considerable potential as a natural catalytic surface for the start of biochemical evolution. Biomolecules should have become available by catalysis of amino acids, etc. The honeycomb would have provided access to various mineral inclusions in the feldspar, particularly apatite and oxides, which contain phosphorus and transition metals necessary for energetic life. The organized environment would have protected complex molecules from dispersion into dilute solutions...

Response of microbial adhesives and biofilm matrix polymers to chemical treatments as determined by interference reflection microscopy and light section microscopy.

Marshall, P A; Loeb, G I; Cowan, M M; Fletcher, M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1989 EN
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The polymers involved in the adhesion of Pseudomonas fluorescens H2S to solid surfaces were investigated to determine whether differences between cell surface adhesives and biofilm matrix polymers could be detected. Two optical techniques, i.e., interference reflection microscopy (IRM) and light section microscopy (LSM), were used to compare the responses of the two types of polymer to treatment with electrolytes, dimethyl sulfoxide (DMSO), and Tween 20. To evaluate initial adhesive polymers, P. fluorescens H2S cells were allowed to attach to glass cover slip surfaces and were immediately examined with IRM, and their response to chemical solutions was tested. With IRM, changes in cell-substratum separation distance between 0 and ca. 100 nm are detectable as changes in relative light intensity of the image; a contraction of the polymer would be detected as a darkening of the image, whereas expansion would appear as image brightening. To evaluate the intercellular polymer matrix in biofilms, 3-day-old biofilms were exposed to similar solutions, and the resultant change in biofilm thickness was measured with LSM, which measures film thicknesses between 10 and 1,000 microns. The initial adhesive and biofilm polymers were similar in that both appeared to contract when treated with electrolytes and to expand when treated with Tween 20. However...

Pronounced enhancement of .NO-dependent antimicrobial action by an .NO-oxidizing agent, imidazolineoxyl N-oxide.

Yoshida, K; Akaike, T; Doi, T; Sato, K; Ijiri, S; Suga, M; Ando, M; Maeda, H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1993 EN
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The antimicrobial action of .NO against Cryptococcus neoformans was investigated by using imidazolineoxyl N-oxide, which we recently reported removes .NO via oxidation (T. Akaike, M. Yoshida, Y. Miyamoto, K. Sato, M. Kohno, K. Sasamoto, K. Miyazaki, S. Ueda, and H. Maeda, Biochemistry 32:827-832, 1993). No appreciable fungicidal activity was observed in neutral .NO solutions. Imidazolineoxyl N-oxide induced or enhanced fungicidal action in neutral or acidic .NO solutions, respectively. Our results provide convincing evidence that .NO is not a microbicidal molecular species.

Conformational lability of poly(dG-m5dC):poly(dG-m5dC).

Chen, F M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 25/06/1986 EN
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The remarkable conformational lability of poly(dG-m5dC):poly(dG-m5dC) is demonstrated by the observation of an acid-mediated conformational hysteresis. An acid-mediated Z conformation that exists in solutions containing low sodium concentrations that would normally favor the B conformation is described in this report. This Z conformation is reached by an acid-base titration of a B-poly(dG-m5dC):poly(dG-m5dC) solution which is not far from the B-Z transition midpoint. The resulting Z conformation is thermally very stable, with direct melting into single strands at approximately 100 degrees C. In contrast, the B form DNA, initially in solutions of the same ionic strength but without exposure to acidic pH, exhibits a biphasic melting profile, with conversion into the Z form (with high cooperativity) prior to an eventual denaturation into single strands at around 100 degrees C. Cooling experiments reveal that such biphasic transitions are quite reversible. The transition midpoint for the thermally poised B to Z transformation depends strongly on the NaCl concentration and varies with sample batch. The acid-mediated Z form binds ethidium more weakly than its B counterpart, and the ethidium induced Z to B conversion occurs in a step-wise (non-allosteric) fashion without the requirement of a threshold concentration. The acid-mediated as well as the thermally poised Z conformations are reversed by the addition of EDTA...

High-efficiency liquid-scintillation counting of 14C-labelled material in aqueous solution and determination of specific activity of labelled proteins

Hall, T. C.; Cocking, E. C.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1965 EN
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1. Inexpensive scintillation mixtures are described which enable the detection of as little as 40μμc of 14C in aqueous solution with an efficiency of counting of over 80%. 2. A rapid method for the counting of alkaline, acidic and neutral aqueous solutions of up to 1ml. volume is described. Ethanol or 2-ethoxyethanol is used as blending agent. 3. The scintillation counting of alkaline solutions is applied to the accurate determination of the specific activity of 14C-labelled proteins from plant tissues. 4. Attention has been paid to the importance of a standardized washing procedure for the removal of all traces of radioactive material from glassware.

Optical determination of Cr(VI) using regenerable, functionalized sol-gel monoliths

Carrington, Nathan A.; Thomas, George H.; Rodman, D. Lynn; Beach, David B.; Xue, Zi-Ling
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Transparent, pyridine-functionalized sol-gel monoliths have been formed and their use in Cr(VI) sensing applications demonstrated. The monoliths were immersed in acidic Cr(VI)-containing solutions, and the Cr(VI) uptake was monitored using UV-visible and atomic absorption spectroscopies. At concentrations at the ppm level, the monoliths exhibit a yellow color change characteristic of Cr(VI) uptake, and this can be measured by monitoring the absorption change at about 350 nm using UV-vis spectroscopy. Concentrations at the ppb level are below the limit of detection using this wavelength of 350 nm for measurement. However, by adding a diphenylcarbazide solution to monoliths that have been previously immersed in ppb-level Cr(VI) solutions, a distinct color change takes place within the gels that can be measured at about 540 nm using UV-vis spectroscopy. Concentrations as low as 10 ppb Cr(VI) can be measured using this method. The monoliths can then be regenerated for subsequent sensing cycles by thorough washing with 6.0 M HCl. The factors affecting monolith uptake of Cr(VI) have been explored. In addition, the gels have been characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) measurements.

Homogenous Water Oxidation by a Di-μ-Oxo Dimanganese Complex in the Presence of Ce4+

Tagore, Ranitendranath; Chen, Hongyu; Zhang, Hong; Crabtree, Robert H.; Brudvig, Gary W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 10/06/2007 EN
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O2 evolution was observed upon mixing aqueous [(terpy)(H2O)Mn(O)2Mn(H2O)(terpy)](NO3)3 (1, terpy = 2,2′:6′,6″-terpyridine) with aqueous solutions of Ce4+. However, when the solution of 1 was incubated at pH = 1 (by dissolving in dilute HNO3) before mixing with Ce4+, very small amounts of O2 were observed. This observation of acid-induced deactivation suggests an explanation, both for the previously reported lack of O2 evolution from aqueous solutions of 1 with Ce4+ as oxidant, and the present observation of low amounts of O2 production with the very acidic Ce4+ reagent. Evidence is provided for water being the source of evolved O2, and for the requirement of a high valent multinuclear Mn species for O2 evolution. We test the possibility of complications in the use of cerium ammonium nitrate (CAN) in oxidation chemistry due to the presence of the oxidizable NH4+ ion.

Basal body reorientation mediated by a Ca2+-modulated contractile protein

Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/08/1987 EN
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A rapid, Ca2+-dependent change in the angle between basal bodies (up to 180 degrees) is associated with light-induced reversal of swimming direction (the "photophobic" response) in a number of flagellated green algae. In isolated, detergent-extracted, reactivated flagellar apparatus complexes of Spermatozopsis similis, axonemal beat form conversion to the symmetrical/undulating flagellar pattern and basal body reorientation (from the antiparallel to the parallel configuration) are simultaneously induced at greater than or equal to 10(-7) M Ca2+. Basal body reorientation, however, is independent of flagellar beating since it is induced at greater than or equal to 10(- 7) M Ca2+ when flagellar beating is inhibited (i.e., in the presence of 1 microM orthovanadate in reactivation solutions; in the absence of ATP or dithiothreitol in isolation and reactivation solutions), or when axonemes are mechanically removed from flagellar apparatuses. Although frequent axonemal beat form reversals were induced by varying the Ca2+ concentration, antiparallel basal body configuration could not be restored in isolated flagellar apparatuses. Observations of the photophobic response in vivo indicate that even though the flagella resume the asymmetric, breaststroke beat form 1-2 s after photostimulation...

Phospholipid-Cholesterol Membrane Model : Control of resistance by ions or current flow

Tobias, Julian M.; Agin, Daniel P.; Pawlowski, Raymond
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/05/1962 EN
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A cephalin-cholesterol membrane model is described whose electrical resistance can be reversibly raised by CaCl2 or lowered by KCl or NaCl whether these ions are added to the membrane by mechanical immersion or are driven in electrically. Either KCl or NaCl acts antagonistically to CaCl2. Experiments with controlled pH indicate that the above effects depend somehow on combination of the cations with the phospholipid acidic groups. Also, they are correlated with decreased membrane hydration in CaCl2 solutions, and increased hydration in KCl or NaCl solutions. It is conjectured that cells may regulate their transsurface ion pathways and fluxes by K-Ca competition for negatively charged binding sites on plasma membrane phospholipid. It is regarded as a corollary to say that a fundamental event in excitation is displacement of membrane Ca from such a site by catelectrotonically propelled K.

Hydrogen ion modulation of Ca channel current in cardiac ventricular cells. Evidence for multiple mechanisms

Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/05/1988 EN
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We have investigated the effects of H ions on (L-type) Ca channel current in isolated ventricular cells. We find that the current amplitude is enhanced in solutions that are alkaline relative to pH 7.4 and reduced in solutions acidic to this pH. We measured pH0-induced shifts in channel gating and analyzed our results in terms of surface potential theory. The shifts are well described by changes in surface potential caused by the binding of H ions to negative charges on the cell surface. The theory predicts a pK of 5.8 for this binding. Gating shifts alone cannot explain all of our observations on modulation of current amplitude. Our results suggest that an additional mechanism contributes to modification of the current amplitude.

Spectrophotometric studies on the pH of frog skeletal muscle. PH change during and after contractile activity

Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/08/1976 EN
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15.87%
The spectral characteristics of the pH-sensitive dyes neutral red (NR) and bromcresol purple (BCP) were utilized for studies of the changing intracellular pH (pHi) of sartorius muscles from Rana pipiens, both during the course of an isometric twitch and during recovery metabolism subsequent to a train of twitches. The information from the two dissimilar dyes correlated to confirm the methodology. Neither the fast realkalinization observed during a twitch nor the slow alkalizing phase of recovery metabolism was affected in an obvious manner when phosphocreatine (PC) hydrolysis was blocked by 1-fluoro-2,4- dinitrobenzene (FDNB). Iodoacetic acid (IAA) did inhibit the slow acidic phase of recovery metabolism. The conclusion is made that alkalizing reactions other than PC breakdown must be considered as operative at these levels of activity. Hypertonic solutions altered twitch tension and time course without altering the pHi shifts observed until approximately 75% of the twitch amplitude was abolished. Multiple effects of hypertonic solutions as the muscle approach tonic equilibrium are proposed.

A Simple and Selective Spectrophotometric Method for the Determination of Trace Gold in Real, Environmental, Biological, Geological and Soil Samples Using Bis (Salicylaldehyde) Orthophenylenediamine

Soomro, Rubina; Ahmed, M. Jamaluddin; Memon, Najma; Khan, Humaira
Fonte: Libertas Academica Publicador: Libertas Academica
Tipo: Artigo de Revista Científica
Publicado em 29/08/2008 EN
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A simple high sensitive, selective, and rapid spectrophotometric method for the determination of trace gold based on the rapid reaction of gold(III) with bis(salicylaldehyde)orthophenylenediamine (BSOPD) in aqueous and micellar media has been developed. BSOPD reacts with gold(III) in slightly acidic solution to form a 1:1 brownish-yellow complex, which has an maximum absorption peak at 490 nm in both aqueous and micellar media. The most remarkable point of this method is that the molar absorptivities of the gold-BSOPD complex form in the presence of the nonionic TritonX-100 surfactant are almost a 10 times higher than the value observed in the aqueous solution, resulting in an increase in the sensitivity and selectivity of the method. The apparent molar absorptivities were found to be 2.3 × 104 L mol−1 cm−1 and 2.5 × 105 L mol−1 cm−1 in aqueous and micellar media, respectively. The reaction is instantaneous and the maximum absorbance was obtained after 10 min at 490 nm and remains constant for over 24 h at room temperature. The linear calibration graphs were obtained for 0.1–30 mg L−1 and 0.01–30 mg L−1 of gold(III) in aqueous and surfactant media, respectively. The interference from over 50 cations, anions and complexing agents has been studied at 1 mg L−1 of Au(III); most metal ions can be tolerated in considerable amounts in aqueous micellar solutions. The Sandell’s sensitivity...

A new crystal modification of diammonium hydrogen phosphate, (NH4)2(HPO4)

Kunz, Peter C.; Wetzel, Corinna; Spingler, Bernhard
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 20/03/2010 EN
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The addition of hexa­fluorido­phosphate salts (ammonium, silver, thallium or potassium) is usually used to precipitate complex cations from aqueous solutions. It has long been known that PF6 − is sensitive towards hydrolysis under acidic conditions [Gebala & Jones (1969 ▶). J. Inorg. Nucl. Chem. 31, 771–776; Plakhotnyk et al. (2005 ▶). J. Fluorine Chem. 126, 27–31]. During the course of our investigation into coinage metal complexes of diphosphine ligands, we used ammonium hexa­fluorido­phosphate in order to crystallize [Ag(diphos­phine)2]PF6 complexes. From these solutions we always obtained needle-like crystals which turned out to be the title compound, 2NH4 +·HPO4 2−. It was received as the hydrolysis product of NH4PF6. The crystals are a new modification of diammonium hydrogen phosphate. In contrast to the previously published polymorph [Khan et al. (1972 ▶). Acta Cryst. B28, 2065–2069], Z′ of the title compound is 2. In the new modification of the title compound, there are eight mol­ecules of (NH4)2(HPO4) in the unit cell. The structure consists of PO3OH and NH4 tetra­hedra, held together by O—H⋯O and N—H⋯O hydrogen bonds.

III. Co-electrodeposition/removal of copper and nickel in a spouted electrochemical reactor

Grimshaw, Pengpeng; Calo, Joseph M.; Hradil, George
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 11/07/2011 EN
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Results are presented of an investigation of co-electrodeposition of copper and nickel from acidic solution mixtures in a cylindrical spouted electrochemical reactor. The effects of solution pH, temperature, and applied current on metal removal/recovery rate, current efficiency, and corrosion of the deposited metals from the cathodic particles were examined under galvanostatic operation. The quantitative and qualitative behavior of co-electrodeposition of the two metals from their mixtures differs significantly from that of the individual single metal solutions. This is primarily attributed to the metal displacement reaction between Ni0 and Cu2+. This reaction effectively reduces copper corrosion, and amplifies that for nickel (at least at high concentrations). It also amplifies the separation of the deposition regimes of the two metals in time, which indicates that the recovery of each metal as a relatively pure deposit from the mixture is possible. It was also shown that nitrogen sparging considerably increases the observed net electrodeposition rates for both metals – considerably more so than from solutions with just the single metals alone. A numerical model of co-electrodeposition, corrosion, metal displacement, and mass transfer in the cylindrical spouted electrochemical reactor is presented that describes the behavior of the experimental copper and nickel removal data quite well.

Crystallographic and X-ray absorption spectroscopic characterization of Helicobacter pylori UreE bound to Ni2+ and Zn2+ reveal a role for the disordered C-terminal arm in metal trafficking

Banaszak, Katarzyna; Martin-Diaconescu, Vlad; Bellucci, Matteo; Zambelli, Barbara; Rypniewski, Wojciech; Maroney, Michael J.; Ciurli, Stefano
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/02/2012 EN
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The survival and growth of the pathogen Helicobacter pylori in the gastric acidic environment is ensured by the activity of urease, an enzyme containing two essential Ni2+ ions in the active site. The metallo-chaperone UreE facilitates in vivo Ni2+ insertion into the apo-enzyme. Crystals of apo-HpUreE and its Ni2+ and Zn2+ bound forms were obtained from protein solutions in the absence and presence of the metal ions. The crystal structures of the homodimeric protein, determined at 2.00 Å (apo), 1.59 Å (Ni) and 2.52 Å (Zn) resolution, show the conserved proximal and solvent-exposed His102 residues from two adjacent monomers invariably involved in metal binding. The C-terminal regions of the apo-protein are disordered in the crystal, but acquire significant ordering in the presence of the metal ions due to the binding of His152. The analysis of X-ray absorption spectral data obtained on solutions of Ni2+- and Zn2+-HpUreE provided accurate information of the metal ion environment in the absence of solid-state effects. These results reveal the role of the histidine residues at the protein C-terminus in metal ion binding, and the mutual influence of protein framework and metal ion stereo-electronic properties in establishing coordination number and geometry leading to metal selectivity.

A New Neutral-pH Low-GDP Peritoneal Dialysis Fluid

Himmele, Rainer; Jensen, Lynn; Fenn, Dominik; Ho, Chih-Hu; Sawin, Dixie-Ann; Diaz-Buxo, Jose A.
Fonte: Multimed Inc Publicador: Multimed Inc
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
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♦ Background: Conventional peritoneal dialysis fluids (PDFs) consist of ready-to-use solutions with an acidic pH. Sterilization of these fluids is known to generate high levels of glucose degradation products (GDPs). Although several neutral-pH, low-GDP PD solutions have been developed, none are commercially available in the United States. We analyzed pH and GDPs in Delflex Neutral pH (Fresenius Medical Care North America, Waltham, MA, USA), the first neutral-pH PDF to be approved by the US Food and Drug Administration.

Surface Degradation of Dental Ceramics as a Function of Environmental pH

Esquivel-Upshaw, J.F.; Dieng, F.Y.; Clark, A.E.; Neal, D.; Anusavice, K.J.
Fonte: SAGE Publications Publicador: SAGE Publications
Tipo: Artigo de Revista Científica
Publicado em /05/2013 EN
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We tested the hypotheses that glass-ceramic veneers and overglazes degrade by ion exchange in an acidic environment, and that they degrade by breakdown of the silica network in a basic environment. Disk specimens of glass-ceramic veneer and glaze were fabricated and immersed in pH 2, 7, or 10 buffer solutions, for 1, 3, 5, 10, 15, and 30 days. Each specimen was placed in a shaker bath containing de-ionized distilled water at 80°C. Concentrations of Al3+, Ca2+, Zn2+, Li2+, and Si4+ were analyzed by means of inductively coupled plasma atomic emission spectrometry (ICP/AES). Statistical analyses were performed by factorial ANOVA. Significant differences occurred among leached ion concentrations as a function of material type, solution pH, and exposure time. A substantial release of Si occurred at pH 10 over time, leading to a breakdown of the glass phase. At pH 2, dissolution was controlled by an ionic exchange mechanism. We conclude that ceramic veneers and glazes may be susceptible to considerable degradation in low- and high-pH buffer solutions.

Anodic Voltammetry of Thioacetamide and its Amperometric Determination in Aqueous Media

Cinghiţă, Dan; Radovan, Ciprian; Dascălu, Daniela
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 04/08/2008 EN
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TAA is a harmful, presumptive pollutant in tap waters and waste waters. Several alternatives have been tested as new possibilities for the anodic determination of TAA in aqueous solutions, simulated waste waters and tap water. The electrochemical behaviour of thioacetamide (TAA) was investigated at a boron-doped diamond (BDD) electrode both in unbuffered 0.1 M Na2SO4 and buffered solutions as supporting electrolytes. The anodic oxidation of TAA showed well-defined limiting currents or current peaks and a good linearity of the amperometric signal vs. concentration plots. The analytical parameters of sensitivity, RSD and LOD, obtained under various experimental conditions, suggest the suitability of the BDD electrode for electroanalytical purposes. Low fouling effects, good reproducibility and stability, as well as the sharpness of the amperometric signals in both unbuffered/ buffered acidic or neutral media, highly superior to those obtained using a glassy carbon (GC) electrode, recommend the unmodified BDD electrode as a promising potential amperometric sensor for environmental applications, regarding the direct anodic determination of TAA in aqueous media.

Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

Rani, Babita; Kumar, Vivek; Singh, Jagvijay; Bisht, Sandeep; Teotia, Priyanku; Sharma, Shivesh; Kela, Ritu
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica
Publicado em 09/10/2014 EN
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Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination.