Search Results - "Velkova, Zdravka"

Biosorption of Congo Red and Methylene Blue by pretreated waste Streptomyces fradiae biomass - Equilibrium, kinetic and thermodynamic studies by Velkova, Zdravka Yancheva, Kirova, Gergana Kirilova, Stoytcheva, Margarita S, Gochev, Velizar

“…Pretreated waste Streptomyces fradiae biomass was utilized as an eco-friendly sorbent for Congo Red (CR) and Methylene Blue (MB) removal from aqueous…”
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Tetracycline removal from model aqueous solutions by pretreated waste Streptomyces fradiae biomass by Kirova, Gergana, Velkova, Zdravka, Stoytcheva, Margarita, Gochev, Velizar

“…Pretreated waste Streptomyces fradiae biomass was used as biosorbent to remove tetracycline (TC) from model aqueous solutions. The biosorption study was…”
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Novel composite biosorbent from Bacillus cereus for heavy metals removal from aqueous solutions by Todorova, Kostadinka, Velkova, Zdravka, Stoytcheva, Margarita, Kirova, Gergana, Kostadinova, Sonia, Gochev, Velizar

“…Waste biomass from Bacillus cereus immobilized in sodium alginate and co-immobilized with activated carbon or with bentonite into alginate gel was studied for…”
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A nanotechnological approach to biosensors sensitivity improvement: application to organophosphorus pesticides determination by Stoytcheva, Margarita, Zlatev, Roumen, Montero, Gisela, Velkova, Zdravka, Gochev, Velizar

“…An electrochemical organophosphorus hydrolase-based sensor for direct organophosphorus pesticides determination was developed, analytically characterized and…”
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Rapid disposable lipase activity sensor for automatic industrial application by Zlatev, Roumen, Stoytcheva, Margarita, Gochev, Velizar, Velkova, Zdravka, Valdez, Benjamín, Montero, Gisela

“…A low-cost disposable lipase activity sensor was developed and characterized overcoming the main drawbacks of the already existing disposable ones:…”
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Vanadium-Containing Anionic Chelate for Spectrophotometric Determination of Hydroxyzine Hydrochloride in Pharmaceuticals by Kirova, Gergana Kirilova, Velkova, Zdravka Yancheva, Delchev, Vassil Borisov, Gavazov, Kiril Blazhev

“…Four azo dyes known to form anionic complexes with V(V) were investigated as potential liquid-liquid extraction-spectrophotometric reagents for the…”
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Biosorption of Pb(II) ions from aqueous solutions by waste biomass of Streptomyces fradiae pretreated with NaOH by Kirova, Gergana, Velkova, Zdravka, Stoytcheva, Margarita, Hristova, Yana, Iliev, Ivan, Gochev, Velizar

“…Biosorption of Pb(II) ions from a model solution was investigated using Streptomyces fradiae biomass as biosorbent pretreated with sodium hydroxide. The…”
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Hexavalent chromium removal by waste mycelium of Aspergillus awamori by VELIZAR K. GOCHEV, ZDRAVKA I. VELKOVA, MARGARITA S. STOYTCHEVA

“…In this study, the Cr(VI) removal potential of waste mycelium from the industrial xylanase-producing strain Aspergillus awamori was evaluated. It was…”
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Immobilized microbial biosorbents for heavy metals removal by Velkova, Zdravka, Kirova, Gergana, Stoytcheva, Margarita, Kostadinova, Sonia, Todorova, Kostadinka, Gochev, Velizar

“…Intensive industrial and urban growth has led to the release of increasing amounts of environmental pollutants. Contamination by metals, in particular,…”
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Adsorptive Stripping Voltammetric Determination of 2,4‐Dichlorophenol by Laponite Modified Carbon Paste Electrode by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Ayala, Alan, Montero, Gisela, Valdez, Benjamín

“…A laponite modified carbon paste electrode was prepared, characterized and applied for the 2,4‐dichlorophenol (2,4‐DCP) voltammetric determination. It takes…”
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Stripping Voltammetric Determination of Methyl Parathion at Activated Carbon Nanopowder Modified Electrode by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Montero, Gisela, Valdez, Benjamín, Curiel, Mario

“…An activated carbon nanopowder modified glassy carbon electrode (AC‐GCE) was constructed for the sensitive determination of methyl parathion by adsorptive…”
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An Affordable and Efficient Graphite‐Coated Electrode for the Voltammetric Determination of Catechol by Stoytcheva, Margarita, Velkova, Zdravka, Gochev, Velizar, Valdez, Benjamin, Curiel, Mario

“…An affordable and highly efficient graphite‐coated electrode was developed and applied in this work as a compelling alternative to other modified electrodes in…”
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Improving the Analytical Performances of the Ibuprofen Voltammetric Determination at Bare Graphite Electrode Using Semi-Derivative Linear Sweep Voltammetry by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Valdez, Benjamin, Kirova, Gergana, Hristova, Yana

“…In this work, a bare graphite electrode was applied for the simple and cost-effective ibuprofen determination. Analytical performances improvement was achieved…”
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The validity of using bare graphite electrode for the voltammetric determination of paracetamol and caffeine by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Meza, Claudia, Valdez, Benjamin, Kirova, Gergana, Hristova, Yana, Toscano-Palomar, Lydia

“…The validity of applying the readily available bare spectroscopic graphite electrode in the pharmaceutical analysis as a cost-effective, simple, and efficient…”
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Simultaneous Determination of Hydroquinone and Catechol by Differential Alternative Pulses Voltammetry by Ayala, Alan, Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Valdez, Benjamin, Montero, Gisela

“…The second order voltammetric technique of high resolution, Differential Alternative Pulses Voltammetry (DAPV), was applied for the simultaneous determination…”
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Bi‐enzyme Electrochemical Sensor for Selective Determination of Organophosphorus Pesticides with Phenolic Leaving Groups by Stoytcheva, Margarita, Zlatev, Roumen, Montero, Gisela, Velkova, Zdravka, Gochev, Velizar

“…An amperometric bi‐enzyme sensor for detection of organophosphorus pesticides (OPs) with phenolic leaving groups, which are not electroactive, is presented in…”
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Resolution of a Mononitrophenol Isomers Mixture by Differential Alternative Pulses Voltammetry by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Ayala, Alan, Montero, Gisela, Valdez, Benjamín

“…The high resolution second order voltammetric technique, Differential Alternative Pulse Voltammetry (DAPV), was applied for the simultaneous quantification of…”
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Diazirine‐functionalized Nanostructured Platform for Enzymes Photografting and Electrochemical Biosensing by Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Ayala, Alan, Montero, Gisela, Valdez, Benjamín

“…A simple technique for the construction of a versatile diazirine‐functionalized nanostructured platform for enzymes photografting and electrochemical…”
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First Order Derivative of Differential Pulse Voltammetry for the Selective and Sensitive 4‐Nitrophenol Determination in the Presence of 2‐Nitrophenol at a Bare Graphite Electrode by Stoytcheva, Margarita, Velkova, Zdravka, Gochev, Velizar, Toscano‐Palomar, Lydia, Valdez, Benjamin, Curiel, Mario

“…Derivative processing of the signal obtained by differential pulse voltammetry was applied in this work as a simple strategy to achieve the sensitive and…”
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Erratum: Simultaneous Determination of Hydroquinone and Catechol by Differential Alternative Pulses Voltammetry by Ayala, Alan, Stoytcheva, Margarita, Zlatev, Roumen, Velkova, Zdravka, Gochev, Velizar, Valdez, Benjamin, Montero, Gisela

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