Applicability of the Electrochemical Oxygen Sensor for In-Situ Evaluation of MgO Solubility in the MgF2–LiF Molten Salt Electrolysis System

The measurement and evaluation of MgO solubility in the molten fluoride system is of significant importance in the recently proposed magnesium electrolysis reduction process. In the present study, an in-situ quantitative method of evaluating the concentration of dissolved MgO in molten fluoride is proposed. The MgO solubility in the 32.8MgF2–67.2LiF system was measured at 1083 and 1123 K using a combustion analyzer. MgO saturation was achieved in under 2 h, and higher solubilities were observed as the temperature increased. Thermodynamic assessment was carried out in order to ascertain the applicability of the electrochemical oxygen sensor, which indicated that the logarithm of oxygen concentration in molten fluoride has a linear relationship with the measured electromotive force (EMF) potential. The EMF potential of the controlled MgO concentration was measured, and a straight calibration line was obtained, describing the relationship between the measured EMF and the logarithm of MgO concentration. From the obtained calibration line, MgO concentration in the 0.4 wt% MgO was calculated. The calculated value was 0.44 wt% that was in excellent accordance with the controlled MgO concentration of 0.4 wt%, verifying the practical applicability of electrochemical oxygen for the in-situ monitoring and evaluation of MgO solubility in the electrolysis magnesium reduction process.

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Fine-tuning and cloning of a fiber-optic probe for in situ monitoring and evaluation of quality of olive oil products

Proceedings of the 18th International Conference on Near Infrared Spectroscopy ◽

10.1255/nir2017.115 ◽

2019 ◽

pp. 115-122

Author(s):

D. Pérez-Marín ◽

J.A. Adame-Siles ◽

F. Sánchez-Müller ◽

F. Maroto-Molina ◽

A. Garrido-Varo

Keyword(s):

Olive Oil ◽

Fiber Optic ◽

Monitoring And Evaluation ◽

Oil Products ◽

Fine Tuning ◽

In Situ Monitoring ◽

Fiber Optic Probe ◽

Optic Probe

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Application of Acoustic Emission Method and Impact Echo Method to Structural Rehabilitation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.776.81 ◽

2018 ◽

Vol 776 ◽

pp. 81-85 ◽

Cited By ~ 1

Author(s):

Luboš Pazdera ◽

Richard Dvořák ◽

Michaela Hoduláková ◽

Libor Topolář ◽

Karel Mikulášek ◽

...

Keyword(s):

Acoustic Emission ◽

Structural Integrity ◽

Concrete Structures ◽

Monitoring And Evaluation ◽

In Situ Monitoring ◽

Impact Echo ◽

Non Destructive ◽

Impact Echo Method ◽

Destructive Methods

The paper is concerned with the technical aspects of the appraisal and retrofitting process of fire damaged reinforced concrete structures. The assessment of fire damaged structures is carried out along lines similar to those of the appraisal of existing structures. In practice, constructions are most often assessed by destructive tests in-situ and on core bore specimens. In addition to destructive tests, damaged structures are also assessed by non-destructive ones. The present paper shows the use of non-destructive methods of measurement using the acoustic-emission and impact-echo methods. Acoustic emission provides valuable data on the structural integrity of a material. This method has a significant potential to be used for in-situ monitoring and evaluation of the current state of structures. An impact-echo method is based on impact-generated stress waves that propagate through concrete and are reflected by internal flaws and external surfaces. Impact-echo can be used to determine the location and extent of flaws such as crack delamination, voids, honeycombing and deboning in plain, reinforced, and post-tensioned concrete structures. The paper presents a possible rehabilitation plan based on the potential results obtained by these non-destructive methods.

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In-situ monitoring by thermal lens microscopy of a photocatalytic reduction process of hexavalent chromium

Revista Mexicana de Física ◽

10.31349/revmexfis.64.507 ◽

2018 ◽

Vol 64 (5) ◽

pp. 507

Author(s):

E Cedeño ◽

J. Plazas-Saldaña ◽

F. Gordillo-Delgado ◽

A. Bedoya ◽

Ernesto Marin

Keyword(s):

Calibration Curve ◽

Thermal Lens ◽

Sol Gel ◽

Colorimetric Method ◽

Reduction Process ◽

Dip Coating ◽

In Situ Monitoring ◽

Probe Laser ◽

A Cell

In this work, we describe the application of a micro-spatial thermal lens spectroscopy setup (thermal lens microscope, TLM) with coaxial counter-propagating pump and probe laser beams and an integrated passive optical Fabry-Perot to quantify the Cr-VI concentration in water during a photocatalytic reaction in-situ. A series of test samples was analyzed using the 1,5 diphenil carbazide colorimetric method. A calibration curve was obtained by plotting of the TLM signal as a function of the concentration of Cr(VI) in a range between 0 and 10 μg/L (1 μg/L = 1 ppb, part per billion), with a detection limit of 53 ng/L (1 ng/L = 1 ppt, part per trillion). A solution of 10 μg/L Cr(VI) in distillated water was placed into a cell in contact with an iron-incorporated titanium dioxide film, which was previously grown onto a 1 mm thick glass microscope slide by the sol-gel dip-coating technique. The TLM signal was registered as a function of the photocatalysis time measured from the beginning of the process, radiating the film with UV-violet light. The Cr(VI) concentration was determined with the calibration curve and after the first 50 minutes a reduction of 95 % of Cr(VI) was observed, being the chemical reaction kinetic described by a potential time decreasing function.

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