817 results on '"electrochemical method"'
Search Results
802. A sensitive DNA biosensor fabricated from gold nanoparticles and graphene oxide on a glassy carbon electrode.
- Author
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Hajihosseini S, Nasirizadeh N, Hejazi MS, and Yaghmaei P
- Subjects
- DNA, Bacterial chemistry, Electrodes, Biosensing Techniques methods, Carbon chemistry, DNA, Bacterial analysis, Graphite chemistry, Helicobacter pylori chemistry, Metal Nanoparticles chemistry
- Abstract
A sensitive electrochemical DNA biosensor was developed for Helicobacter pylori (H. pylori) detection using differential pulse voltammetry. Single-stranded DNA probe was immobilized on a graphene oxide/gold nanoparticles modified glassy carbon electrode (GO/AuNPs/GCE). A hybridization reaction was conducted with the target DNA and the immobilized DNA on the electrode surface. Oracet blue (OB) was selected for the first time as a redox indicator for amplifying the electrochemical signal of DNA. Enhanced sensitivity was achieved through combining the excellent electric conductivity of GO/AuNPs and the electroactivity of the OB. The DNA biosensor displayed excellent performance to demonstrate the differences between the voltammetric signals of the OB obtained from different hybridization samples (non-complementary, mismatch and complementary DNAs). The proposed biosensor has a linear range of 60.0-600.0 pM and a detection limit of 27.0 pM for detection of H. pylori. In addition, the biosensor have responded very well in the simulated real sample evaluations, signifying its potential to be used in future clinical detection of the H. pylori bacteria., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
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803. Electrochemical assay of α-glucosidase activity and the inhibitor screening in cell medium.
- Author
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Zhang J, Liu Y, Wang X, Chen Y, and Li G
- Subjects
- Animals, Cell Line, Culture Media metabolism, Enzyme Activation, Equipment Design, Equipment Failure Analysis, Magnetite Nanoparticles ultrastructure, Reproducibility of Results, Sensitivity and Specificity, Swine, alpha-Glucosidases chemistry, Biosensing Techniques instrumentation, Conductometry instrumentation, Epithelial Cells metabolism, Glycoside Hydrolase Inhibitors analysis, Magnetite Nanoparticles chemistry, alpha-Glucosidases metabolism
- Abstract
An electrochemical method is established in this work for the assay of α-glucosidase activity and the inhibitor screening through one-step displacement reaction, which can be directly used in cell medium. The displacement reaction can be achieved via strong binding of 4-aminophenyl-α-D-glucopyranoside (pAPG)/magnetic nanoparticles (MNPs) to pyrene boric acid (PBA) immobilized on the surface of graphite electrode (GE), compared to that of dopamine (DA)/sliver nanoparticles (AgNPs). Since α-glucosidase can specifically catalyze MNPs/pAPG into MNPs/pAP which has no binding capacity with PBA, the activity of both isolated and membrane bound enzyme can be well evaluated by using this proposed method. Meanwhile, signal amplification can be accomplished via the immobilization of DA at the outer layer of AgNPs, and the accuracy can be strengthened through magnetic separation. Moreover, this method can also be utilized for inhibitor screening not only in the medium containing the enzyme but also in cell medium. With good precision and accuracy, it may be extended to other proteases and their inhibitors as well., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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804. Neural Cell Chip Based Electrochemical Detection of Nanotoxicity.
- Author
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Kafi MA, Cho HY, and Choi JW
- Abstract
Development of a rapid, sensitive and cost-effective method for toxicity assessment of commonly used nanoparticles is urgently needed for the sustainable development of nanotechnology. A neural cell with high sensitivity and conductivity has become a potential candidate for a cell chip to investigate toxicity of environmental influences. A neural cell immobilized on a conductive surface has become a potential tool for the assessment of nanotoxicity based on electrochemical methods. The effective electrochemical monitoring largely depends on the adequate attachment of a neural cell on the chip surfaces. Recently, establishment of integrin receptor specific ligand molecules arginine-glycine-aspartic acid (RGD) or its several modifications RGD-Multi Armed Peptide terminated with cysteine (RGD-MAP-C), C(RGD)₄ ensure farm attachment of neural cell on the electrode surfaces either in their two dimensional (dot) or three dimensional (rod or pillar) like nano-scale arrangement. A three dimensional RGD modified electrode surface has been proven to be more suitable for cell adhesion, proliferation, differentiation as well as electrochemical measurement. This review discusses fabrication as well as electrochemical measurements of neural cell chip with particular emphasis on their use for nanotoxicity assessments sequentially since inception to date. Successful monitoring of quantum dot (QD), graphene oxide (GO) and cosmetic compound toxicity using the newly developed neural cell chip were discussed here as a case study. This review recommended that a neural cell chip established on a nanostructured ligand modified conductive surface can be a potential tool for the toxicity assessments of newly developed nanomaterials prior to their use on biology or biomedical technologies.
- Published
- 2015
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805. Biological properties of nanostructured Ti incorporated with Ca, P and Ag by electrochemical method.
- Author
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Li B, Hao J, Min Y, Xin S, Guo L, He F, Liang C, Wang H, and Li H
- Subjects
- Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacology, Calcium chemistry, Calcium pharmacology, Cell Survival drug effects, Cell Survival physiology, Electroplating methods, Materials Testing, Metal Nanoparticles administration & dosage, Metal Nanoparticles chemistry, Metal Nanoparticles ultrastructure, Nanotubes ultrastructure, Osseointegration drug effects, Particle Size, Phosphorus chemistry, Phosphorus pharmacology, Silver chemistry, Silver pharmacology, Surface Properties, Titanium pharmacology, Bacterial Physiological Phenomena drug effects, Coated Materials, Biocompatible chemical synthesis, Coated Materials, Biocompatible pharmacology, Nanotubes chemistry, Osseointegration physiology, Titanium chemistry
- Abstract
TiO2 nanotube arrays were synthesized on Ti surface by anodic oxidation. The elements of Ca and P were simultaneously incorporated during nanotubes growth in SBF electrolyte, and then Ag was introduced to nanotube arrays by cathodic deposition, which endowed the good osseointegration and antibacterial property of Ti. The bioactivity of the Ti surface was evaluated by simulated body fluid soaking test. The biocompatibility was investigated by in vitro cell culture test. And the antibacterial effect against Staphylococcus aureus was examined by the bacterial counting method. The results showed that the incorporation of Ca, P and Ag elements had no significant influence on the formation of nanotube arrays on Ti surface during electrochemical treatment. Compared to the polished or nanotubular Ti surface, TiO2 nanotube arrays incorporated with Ca, P and Ag increased the formation of bone-like apatite in simulated body fluid, enhanced cell adhesion and proliferation, and inhibited the bacterial growth. Based on these results, it can be concluded that the nanostructured Ti incorporated with Ca, P and Ag by electrochemical method has promising applications as implant material., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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806. Simultaneous determination of the isomers of Ponceau 4R and Amaranth using an expanded graphite paste electrode.
- Author
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Zhang J, Wang M, Shentu C, Wang W, and Chen Z
- Subjects
- Electrochemical Techniques, Electrodes, Graphite chemistry, Hydrogen-Ion Concentration, Isomerism, Reproducibility of Results, Amaranth Dye analysis, Azo Compounds analysis, Coloring Agents analysis, Naphthalenesulfonates analysis
- Abstract
A sensitive and convenient electrochemical method was developed for the simultaneous determination of the isomers of Ponceau 4R and Amaranth by an expanded graphite paste electrode (EGPE). The EGPE was prepared by mixing EG with solid paraffin. Compared with flake graphite paste and carbon paste electrodes, the EGPE showed higher electrocatalytic activity towards the oxidization of Ponceau 4R and Amaranth. Under optimal experimental conditions, the EGPE exhibited wide linear responses to Ponceau 4R and Amaranth ranging from 6×10(-8) to 4×10(-6) mol/L and 8×10(-8) to 4×10(-6)mol/L, respectively, and the detection limits for Ponceau 4R and Amaranth were 2 and 36 nmol/L, respectively, at a signal-to-noise ratio of 3. The EGPE showed good reproducibility, stability and reusability. The proposed method was successfully applied in the detection of Ponceau 4R and Amaranth in grape juice samples., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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807. Binding between lead ions and the high-abundance serum proteins.
- Author
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Guo M, He L, Strong PJ, and Wang H
- Subjects
- Animals, Cattle, Electrochemistry, Models, Chemical, Protein Binding, Serum Albumin metabolism, Blood Proteins metabolism, Environmental Pollutants metabolism, Lead metabolism
- Abstract
The interaction between three of the most abundant bovine serum proteins (serum albumin, transferrin and IgG) with Pb(2+) was investigated using electrochemistry. The data was used to construct a new theoretical model of Pb(2+) binding to the high-abundance serum proteins under non-ideal conditions. The binding constants (β) of Pb(2+) to the individual proteins and a mixture of proteins were measured according to a new theoretical equation (non-ideal state) as well as the McGhee-Von Hippel equation (ideal state). Differences between the models suggested that the β values obtained using the non-ideal state model was more realistic. Protein-protein interactions and micro-environmental influences affected binding between Pb(2+) and the high-abundance serum proteins. We included a micro-environmental influence factor for the model (Fm), which accurately quantified the effect of micro-environment of the proteome of Pb(2+) binding with the serum proteins. This research provides a useful reference of theoretical and experimental work regarding heavy-metal binding interactions with serum proteins., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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808. Redox targeting of DNA anchored to MWCNTs and TiO2 nanoparticles dispersed in poly dialyldimethylammonium chloride and chitosan.
- Author
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Ensafi AA, Nasr-Esfahani P, Heydari-Bafrooei E, and Rezaei B
- Subjects
- Animals, Biosensing Techniques, Electrochemical Techniques, Electrodes, Graphite, Methylene Blue chemistry, Nanoparticles ultrastructure, Nanotubes, Carbon ultrastructure, Oxidation-Reduction, Time Factors, Chitosan chemistry, DNA metabolism, Nanoparticles chemistry, Nanotubes, Carbon chemistry, Polyethylenes chemistry, Quaternary Ammonium Compounds chemistry, Titanium chemistry
- Abstract
A key issue associated with electrochemical DNA-based biosensors is how to enhance DNA immobilization on the substrates. In order to improve the immobilization of DNA and to optimize DNA interaction efficiency, different kinds of strategies have been developed. In this regard, nanomaterials have attracted a great deal of attention in electrode surface modification for DNA biosensor fabrication. In this study, nanostructured films were deposited at the surface of a pencil graphite electrode (PGE) as a working electrode. For the present purpose, common polyelectrolytes are used for surface modification with double-stranded DNA. Two positively charged polyelectrolyte, namely poly dialyldimethylammonium chloride (PDDA) and chitosan, are initially compared for DNA immobilization at the surface of MWCNTs and TiO2 nanoparticles (TiO2NPs). In a second step, the basic electrochemical properties of the sensors are investigated using voltammetric methods. The modified electrodes are also characterized by scanning electron microscopy and electrochemical impedance measurements. It will be shown that electrode modification with DNA and the nanostructure that disperses in PDDA leads to an enhanced sensitivity of the DNA voltammetric detection mechanism. In a previous study, a comparison was done between MWCNTs and TiO2NPs for determining the effect of nanoparticle effect on DNA immobilization on the electrode surface. In order to compare the efficiency of the prepared DNA-based biosensors, methylene blue is chosen as an electroactive probe. It will be shown that the stability of the immobilized DNA within several days will be much higher when MWCNTs rather than TiO2NPs are used., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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809. A novel electrochemical method to evaluate the cytotoxicity of heavy metals.
- Author
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Zhu X, Qin H, Liu J, Zhang Z, Lu Y, Yuan X, and Wu D
- Subjects
- Cell Survival drug effects, Electrodes, Graphite, HeLa Cells, Humans, Tetrazolium Salts metabolism, Thiazoles metabolism, Electrochemical Techniques, Metals, Heavy toxicity, Toxicity Tests methods
- Abstract
There is an ongoing search to develop techniques for detection of heavy metals which are highly toxic and can cause damaging effects even at very low concentrations. In this present study, we report a label-free electrochemical method based on the direct voltammetric response of human cervical carcinoma (HeLa) cells on a highly sensitive graphene modified electrode. Five heavy metals were tested with the method and the results were validated by the traditional methyl tetrazolium (MTT) assay. The results revealed that the most toxic metal was Cr, followed by Cd, Cu, Pb and Zn. A good correlation between the two methods was observed. This work will be beneficial in providing a novel monitoring method to detect hazardous pollutants in the field of environmental toxicology., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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810. Sequence-specific detection of DNA using functionalized graphene as an additive.
- Author
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Tian T, Li Z, and Lee EC
- Subjects
- Base Pair Mismatch, Base Sequence, DNA genetics, Electrodes, Methylene Blue chemistry, Biosensing Techniques methods, DNA isolation & purification, Graphite chemistry
- Abstract
We developed a simple and sensitive method for sequence-specific DNA detection using functionalized graphene (FG) and methylene blue (MB). Target DNA with a specific sequence was identified by differential-pulse voltammetry, which produces a change in the redox currents of the incorporated MB. FG played a critical role in enhancing the sensitivity of DNA detection and reduced the concentration of MB substantially near the electrodes when the sequence of the target DNA was not complementary to that of the probe by adsorbing the single-stranded DNA with the bound MB, and sinking. Our system could detect even single base-pair mismatches between the target and probe. Fabricating this system does not involve a laborious probe-immobilization process and is considerably simpler than fabricating graphene-electrode-based DNA sensors., (© 2013 Published by Elsevier B.V.)
- Published
- 2014
- Full Text
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811. Coating of titanium with hydroxyapatite leads to decreased bone formation: A study in rabbits.
- Author
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Bøe BG, Støen RØ, Solberg LB, Reinholt FP, Ellingsen JE, and Nordsletten L
- Abstract
Objectives: An experimental rabbit model was used to test the null hypothesis, that there is no difference in new bone formation around uncoated titanium discs compared with coated titanium discs when implanted into the muscles of rabbits., Methods: A total of three titanium discs with different surface and coating (1, porous coating; 2, porous coating + Bonemaster (Biomet); and 3, porous coating + plasma-sprayed hydroxyapatite) were implanted in 12 female rabbits. Six animals were killed after six weeks and the remaining six were killed after 12 weeks. The implants with surrounding tissues were embedded in methyl methacrylate and grinded sections were stained with Masson-Goldners trichrome and examined by light microscopy of coded sections., Results: Small amounts of bone were observed scattered along the surface of five of the 12 implants coated with porous titanium, and around one out of 12 porous coated surfaces with Bonemaster. No bone formation could be detected around porous coated implants with plasma-sprayed hydroxyapatite., Conclusion: Porous titanium coating is to some degree osteoinductive in muscles.
- Published
- 2012
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812. Dry-pressed anodized titania nanotube/CH3NH3PbI3 single crystal heterojunctions: The beneficial role of N doping
- Author
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László Forró, Anđelika Bjelajac, Maja Popović, Pavao Andričević, Bálint Náfrádi, Vera P. Pavlović, Konrad Domanski, Đorđe Janaćković, Andreas Schiller, Jelena Vujančević, Endre Horváth, Veljko R. Đokić, Zlatko Rakočević, and Márton Kollár
- Subjects
optical properties ,Nanotube ,Anatase ,photocatalytic activity ,Materials science ,Annealing (metallurgy) ,oxidation ,Titanium dioxide nanotubes ,tio2 nanotube arrays ,chemistry.chemical_element ,02 engineering and technology ,annealing in nh3 ,fabrication ,photocurrent ,01 natural sciences ,titanium dioxide nanotubes ,doped tio2 ,Methylammonium lead triiodide photodetectors ,0103 physical sciences ,Annealing in NH3 ,Materials Chemistry ,Photocurrent ,010302 applied physics ,Thermal oxidation ,methylammonium lead triiodide photodetectors ,Optical properties ,Process Chemistry and Technology ,Doping ,Heterojunction ,021001 nanoscience & nanotechnology ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Titanium oxide ,solar-cells ,Chemical engineering ,chemistry ,thin-films ,Ceramics and Composites ,annealing in NH 3 ,0210 nano-technology ,performance ,Titanium ,electrochemical method - Abstract
Highly ordered, anodically grown TiO 2 nanotubes on titanium supports were annealed in ammonia atmosphere in order to incorporate nitrogen doping (≤2 at.%) in the titanium oxide lattice. FESEM micrographs revealed nanotubes with an average outer diameter of 101.5 ± 1.5 nm and an average wall thickness of about 13 nm. Anatase crystals were formed inside the tubes after annealing in ammonia atmosphere for 30 min. With further annealing, rutile peaks appeared due to the thermal oxidation of the foil and rise as the duration of heat treatment was increased. The concentration and chemical nature of nitrogen in the nanotube arrays can be correlated to the optical response of dry-pressed heterojunctions of doped TiO 2 /CH 3 NH 3 PbI 3 single crystals. The N-TiO 2 /perovskite heterojunction with the highest amount of interstitial nitrogen exhibited an improved photocurrent, indicating the importance of the semiconductor doping-based heterojunction optimization strategies to deliver competitive levels of halide perovskite-based optoelectronic devices to be envisioned for urban infrastructures. © 2019 Supplementary information: [http://dais.sanu.ac.rs/123456789/5969] This is the peer-reviewed version of the article: Vujančević, J., Andričević, P., Bjelajac, A., Đokić, V., Popović, M., Rakočević, Z., ... & Domanski, K. (2019). Dry-pressed anodized titania nanotube/CH3NH3PbI3 single crystal heterojunctions: The beneficial role of N doping. Ceramics International, 45(8), 10013-10020. [http://dx.doi.org/10.1016/j.ceramint.2019.02.045] Published version: [https://vinar.vin.bg.ac.rs/handle/123456789/8538]
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813. Evaluation of mass transfer in a novel hollow fiber module design using an electrochemical technique
- Author
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Cristiano Piacsek Borges, L. S. de França Neta, and Alberto Claudio Habert
- Subjects
Hydrocyclone ,Mass transfer coefficient ,Materials science ,General Chemical Engineering ,lcsh:TP155-156 ,mass transfer coefficient ,02 engineering and technology ,021001 nanoscience & nanotechnology ,020401 chemical engineering ,Hollow fiber membrane ,Mass transfer ,Electrode ,Fluid dynamics ,Electrochemical method ,hollow fiber ,Fiber ,0204 chemical engineering ,Composite material ,lcsh:Chemical engineering ,0210 nano-technology ,Polarization (electrochemistry) ,permeation module - Abstract
The mass transfer coefficient (K L ) determined using an electrochemical technique was used in this work as a parameter to evaluate the hydrodynamics of hollow fiber membrane modules. A new microfiltration module configuration was investigated, taking advantage of the hydrocyclone concept aimed at reducing the concentration of the polarization layer near the membrane surface promoted by the centrifugal field. The mass transfer coefficient for the new configuration was compared with that of a conventional longitudinal module. The experimental determination of K L was obtained by monitoring the electrochemical reactions that occur at the electrode surface under mass transfer-limiting conditions. The performance of the microfiltration modules, both hybrid and longitudinal, was evaluated based on parameters such as packing density and fluid flow regimes. The results achieved for the mass transfer coefficient with the electrochemical technique allowed for performance evaluations of the proposed new module configuration and a comparison with the longitudinal module.
814. Electrochemical determination of chemical oxygen demand in mixed organic solution by Al/SnO2-TiO2 electrode.
- Abstract
Chemical oxygen demand (COD) is one of the most significant parameters in water-quality analysis, such as wastewater effluent monitoring. However, COD determination faces challenges of long measuring time and the use of toxic substances. In this work, an Al/SnO2-TiO2 composite film electrode was prepared using the sol-gel method and dip-coating method for electrochemical determination of COD. The electrocatalytic reaction kinetics of the different organic substances on the electrode was studied in a three-electrode system. It was observed that the electrocatalytic reactions of all tested organic compounds on the Al/SnO2-TiO2 electrode fitted the first-order kinetics. Based on the reaction rate constants at different temperatures, the activation energies for electrocatalytic oxidations of methylene blue and rhodamine B were 9.92 kJ/mol and 14.7 kJ/mol, respectively. It was confirmed that dynamic behaviors of different organic substances on the electrode surface were different from each other. In addition, seven single-component organic solutions, four two-component organic solutions, and three three-component organic solutions were selected as the target standard solutions for the COD measurement experiments. Initial working currents measured by chronocoulometry were taken as the index of the value of COD of the target solutions within the operating voltage range of 1.5∼3.5 V (vs. SCE). In the range of 20∼100 mg/L, COD values of either single-component or multiple-component solutions were linearly related to the initial working currents. For solutions composed of different organic compounds with the identical COD concentration, each of their initial working currents was different from the others and increased with the working voltage. It could be concluded that the initial working currents measured by chronocoulometry was depended on COD concentration, applied voltage, as well as the composition of the tested solutions. By comparing the COD measurement results, using
815. Processing methods with application of an electric field at low waste separation of materials
- Author
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Khafizov Ildar Ilsurovich and Khafizov Ildar Ilsurovich
816. Electrochemical determination of chemical oxygen demand in mixed organic solution by Al/SnO2-TiO2 electrode.
- Abstract
Chemical oxygen demand (COD) is one of the most significant parameters in water-quality analysis, such as wastewater effluent monitoring. However, COD determination faces challenges of long measuring time and the use of toxic substances. In this work, an Al/SnO2-TiO2 composite film electrode was prepared using the sol-gel method and dip-coating method for electrochemical determination of COD. The electrocatalytic reaction kinetics of the different organic substances on the electrode was studied in a three-electrode system. It was observed that the electrocatalytic reactions of all tested organic compounds on the Al/SnO2-TiO2 electrode fitted the first-order kinetics. Based on the reaction rate constants at different temperatures, the activation energies for electrocatalytic oxidations of methylene blue and rhodamine B were 9.92 kJ/mol and 14.7 kJ/mol, respectively. It was confirmed that dynamic behaviors of different organic substances on the electrode surface were different from each other. In addition, seven single-component organic solutions, four two-component organic solutions, and three three-component organic solutions were selected as the target standard solutions for the COD measurement experiments. Initial working currents measured by chronocoulometry were taken as the index of the value of COD of the target solutions within the operating voltage range of 1.5∼3.5 V (vs. SCE). In the range of 20∼100 mg/L, COD values of either single-component or multiple-component solutions were linearly related to the initial working currents. For solutions composed of different organic compounds with the identical COD concentration, each of their initial working currents was different from the others and increased with the working voltage. It could be concluded that the initial working currents measured by chronocoulometry was depended on COD concentration, applied voltage, as well as the composition of the tested solutions. By comparing the COD measurement results, using
817. Etude de l'orientation cristallographique dans un silicium polycristallin massif
- Author
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P. Andonov
- Subjects
X ray diffraction examination of materials ,film thickness ,Materials science ,axially columnar structure ,Crystal orientation ,directional solidification ,02 engineering and technology ,lattice constants ,01 natural sciences ,impurities ,crystallographic orientation ,crystal orientation ,0103 physical sciences ,secondary ion mass spectra ,Anodic dissolution ,grain growth ,crystal growth from melt ,Growth orientation ,010302 applied physics ,anodic dissolution ,silicon ,021001 nanoscience & nanotechnology ,semiconductor growth ,growth orientation ,Crystallography ,[PHYS.HIST]Physics [physics]/Physics archives ,etched surface ,reticular density ,elemental semiconductors ,solidification ,0210 nano-technology ,X rays diffraction ,electrochemical method - Abstract
L'etude de l'orientation cristallographique d'un silicium polycristallin obtenu par solidification directionnelle dans un creuset de graphite est reportee dans ce travail. Les techniques usuelles de diffraction des rayons X par reflexion ont tout d'abord ete utilisees. Des variations de parametres atteignant 14 x 10-4 A ont ete mises en evidence entre les differentes zones de cristallinite du lingot. La croissance des grains, parallelement aux gradients de temperature les plus importants, produit dans le centre du lingot une structure axiale colonnaire avec des orientations privilegiees [211] et [111]. Sur les bords du creuset les orientations de croissance sont differentes. Les orientations [110] et [100] fortement defavorisees augmentent quand le taux d'impuretes (Al + B) devient superieur a 9 x 1015 atomes/cm3. Une methode d'analyse basee sur l'attaque electrochimique du silicium a ete ensuite developpee. L'analyse du depot a ete faite par diffraction des rayons X et par analyse ionique. Une correlation entre son epaisseur et la densite reticulaire du plan de surface attaque a ete etablie. La texture de solidification peut ainsi etre representee sans precision mais tres rapidement par la carte des couleurs de lame mince observee apres l'attaque electrolytique. Cette methode semble bien adaptable pour un controle rapide d'une elaboration industrielle.
- Published
- 1982
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