scholarly journals Design of a Flow-Through Voltammetric Sensor Based on an Antimony-Modified Silver Electrode for Determining Lithol Rubine B in Cosmetics

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Wang Lai-Hao ◽  
Huang Shu-Juan
Keyword(s):  
High Performance ◽  
Disodium Salt ◽  
Voltammetric Sensor ◽  
Acidic Media ◽  
Ultraviolet Detector ◽  
Experimental Parameters ◽  
Constant Potential ◽  
Flow Through ◽  
Antimony Film ◽  
Linear Concentration

Lithol Rubine B (LRB; the disodium salt of 3-hydroxy-4-[(4-methyl-2-sulfophenyl) azo]-2-naphthalenecarboxylic acid) was detected using high-performance liquid chromatography with an electrochemical (antimony film on silver) detector (HPLC-ECD). For direct current (DC) mode, with the current at a constant potential, and measurements with suitable experimental parameters, a linear concentration from 0.125 to 1.80 μg/mL was found. The detection limit of our method was approximately 2.0 ng/mL. An antimony-modified silver detector was used to demonstrate that LRB is electrochemically reduced in acidic media and to analyze commercial cosmetics to determine their LRB content. Findings using HPLC-ECD and HPLC with an ultraviolet detector were comparable.

Electrochemical Detector for Liquid Chromatography: Determining Minoxidil in Hair-Growth Pharmaceuticals

2019 ◽  
Vol 15 (5) ◽  
pp. 575-582
Author(s):  
Lai-Hao Wang ◽  
Pei-Tung Cheng
Keyword(s):  
Liquid Chromatography ◽  
High Performance ◽  
Supporting Electrolyte ◽  
Current Mode ◽  
Carbon Paste ◽  
Electrochemical Detector ◽  
Ultraviolet Detector ◽  
Experimental Parameters ◽  
Constant Potential ◽  
Voltammetric Measurements

Background: The electrochemical behavior of minoxidil on gold (Au), Glassy Carbon (GCEs), and Carbon Paste Electrodes (CPEs) was investigated in an aqueous supporting electrolyte (phosphate buffer [pH 2.0-6.5], acetate buffer [pH 4.3], and Britton and Robinson buffer [pH 2.0-7.4]). Methods: For cyclic voltammetric measurements with suitable methodical parameters, CPEs catalyze electrooxidation of minoxidil more efficiently than do other electrodes. Minoxidil was detected using high-performance liquid chromatography with an electrochemical (carbon paste) detector (HPLCECD). For direct current mode, with the current at a constant potential, and measurements with suitable experimental parameters, a linear concentration from 0.02 to 2.6 mg L-1 was found. The detection limit was approximately 20 ng m L-1. Results: The developed method detected minoxidil samples. Conclusion: Findings using HPLC-ECD and HPLC with an ultraviolet detector were comparable.

scholarly journals Investigation on the La Replacement and Little Additive Modification of High-Performance Permanent Magnetic Strontium-Ferrite

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1034
Author(s):  
Ching-Chien Huang ◽  
Chin-Chieh Mo ◽  
Guan-Ming Chen ◽  
Hsiao-Hsuan Hsu ◽  
Guo-Jiun Shu
Keyword(s):  
High Performance ◽  
Single Phase ◽  
Permanent Magnets ◽  
High Efficiency ◽  
Cobalt Content ◽  
Preparation Condition ◽  
Milling Process ◽  
Experimental Parameters ◽  
La Substitution ◽  
Hard Magnets

In this work, an experiment was carried out to investigate the preparation condition of anisotropic, Fe-deficient, M-type Sr ferrite with optimum magnetic and physical properties by changing experimental parameters, such as the La substitution amount and little additive modification during fine milling process. The compositions of the calcined ferrites were chosen according to the stoichiometry LaxSr1-xFe12-2xO19, where M-type single-phase calcined powder was synthesized with a composition of x = 0.30. The effect of CaCO3, SiO2, and Co3O4 inter-additives on the Sr ferrite was also discussed in order to obtain low-temperature sintered magnets. The magnetic properties of Br = 4608 Gauss, bHc = 3650 Oe, iHc = 3765 Oe, and (BH)max = 5.23 MGOe were obtained for Sr ferrite hard magnets with low cobalt content at 1.7 wt%, which will eventually be used as high-end permanent magnets for the high-efficiency motor application in automobiles with Br > 4600 ± 50 G and iHc > 3600 ± 50 Oe.

Creating Nitrogen-Doped Hollow Multiyolk@Shell Carbon as High Performance Electrodes for Flow-Through Deionization Capacitors

2017 ◽  
Vol 5 (4) ◽  
pp. 3329-3338 ◽  
Author(s):  
Hui Wang ◽  
Tingting Yan ◽  
Liyi Shi ◽  
Guorong Chen ◽  
Jianping Zhang ◽  
...  
Keyword(s):  
High Performance ◽  
Nitrogen Doped ◽  
Flow Through

scholarly journals 3D Porous Fe/N/C Spherical Nanostructures As High-Performance Electrocatalysts for Oxygen Reduction in Both Alkaline and Acidic Media

2017 ◽  
Vol 9 (42) ◽  
pp. 36944-36954 ◽  
Author(s):  
Qiliang Wei ◽  
Gaixia Zhang ◽  
Xiaohua Yang ◽  
Régis Chenitz ◽  
Dustin Banham ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
High Performance ◽  
Acidic Media

Device Used for Magnetic Treatment of Fuel Fluids before Burner

2012 ◽  
Vol 186 ◽  
pp. 214-218 ◽  
Author(s):  
Robert Ciobanu ◽  
Maurizio Repetto ◽  
Octavian Dontu ◽  
Fabio Freschi ◽  
Tudor Prisecaru
Keyword(s):  
Permanent Magnet ◽  
High Performance ◽  
Magnetic Treatment ◽  
Magnetostatic Field ◽  
Combustion Dynamics ◽  
Flow Through

Worldwide magnetism was considered a "stepchild" of electromagnetism, but lately this has changed, and scientists give it great importance today, making a series of studies in which it is the main "actor". Regarding the magnetostatic field, the appearance of magnets with high performance, has led the development of permanent magnet structures with different technical applications, which successfully replace electromagnets. In this paper our main objective was to design and test a device used for magnetic treatment of fuel fluid which flow through pipes before burner to improve combustion dynamics and decrease the released fumes.

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