The relationship between the open-circuit potential of a galena electrode and the dissolved lead concentration

The aim of this research was to study the oxidation and reduction of the adsorbed thiosulfate on the platinum electrode in a slightly alkaline medium. The adsorption was performed at the open circuit conditions. The reduction of the adsorbed layer in the hydrogen region is slower in a slightly alkaline medium than in acid. The mechanism of reduction and oxidation of adsorbed molecules is probably the same. The nonstationary currents measured in presence of thiosulfates showed that the change in the oxidation number does not take place during the adsorption in the double layer region. In the hydrogen region, thiosulfate replaces the adsorbed hydrogen while beeing reduced. Nonstationary currents at higher concentrations of thiosulfate indicate the presence of more layers on the electrode. Upon reaching higher concentrations of thiosulfate the oxidation reaction takes place between thiosulfate in solution and adsorbed product of its reduction. The open circuit potential of the platinum electrode measured in a thiosulfate solution was 0.780 and 0.783 V against the hydrogen electrode in the same solution.

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Effects of Alloying Elements on the Corrosion Behavior of Sputter–deposited Zr–(12–21)Cr–W Alloys in 0.5 M NaCl Solution

Journal of Nepal Chemical Society ◽

10.3126/jncs.v25i0.3305 ◽

1970 ◽

Vol 25 ◽

pp. 75-82

Author(s):

Basu Ram Aryal ◽

Jagadeesh Bhattarai

Keyword(s):

Corrosion Test ◽

Open Circuit Potential ◽

Chemical Society ◽

Open Circuit ◽

Sputter Deposition ◽

Nacl Solution ◽

Corrosion Rates ◽

Sputter Deposited ◽

Stable Passivity ◽

Zirconium Metal

The synergistic effect of the simultaneous additions of tungsten and zirconium in thesputter-deposited amorphous or nanocrystalline Zr-(12-21)Cr-W alloys is studied in 0.5 MNaCl solution open to air at 25°C using corrosion tests and open circuit potentialmeasurements. Corrosion rates of the sputter-deposited Zr-(12-21)Cr-W alloys containing10-80 at % tungsten (that is, 0.95-1.85 x 10-2 mm.y-1) are more than one order of magnitudelower than that of the sputter-deposited tungsten and even lower than those of zirconium aswell as chromium in 0.5 M NaCl solution. The addition of 8-73 at % zirconium content inthe sputter-deposited binary W-(12-21)Cr alloys seems to be more effective to improve thecorrosion-resistant properties of the sputter-deposited ternary Zr-Cr-W alloys containing12-21 at % chromium in 0.5 M NaCl solution. The sputter-deposited Zr-(17-21)Cr-W alloyscontaining an adequate amounts of zirconium metal showed the more stable passivity andshowed higher corrosion resistance than those of alloy-constituting elements in 0.5 M NaClsolution open to air at 25°C.Keywords: Zr-(12-21)Cr-W alloys, sputter deposition, corrosion test, open circuit potential,0.5 M NaCl.DOI: 10.3126/jncs.v25i0.3305Journal of Nepal Chemical Society Volume 25, 2010 pp 75-82

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Miniaturization effect of electroosmotic self-propulsive microswimmer powered by biofuel cell

ROBOMECH Journal ◽

10.1186/s40648-019-0146-x ◽

2019 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Toshiro Yamanaka ◽

Fumihito Arai

Keyword(s):

Theoretical Model ◽

Femtosecond Laser ◽

Polymer Composites ◽

Open Circuit Potential ◽

Vascular System ◽

Conductive Polymer ◽

Open Circuit ◽

Biofuel Cell ◽

Remarkable Feature ◽

Conductive Polymer Composites

AbstractFor future medical microrobotics, we have proposed the concept of the electroosmotic self-propulsive microswimmer powered by biofuel cell. According to the derived theoretical model, its self-propulsion velocity is inversely proportional to the length of the microswimmer, while it is proportional to the open circuit potential generated by the biofuel cell which does not depend on its size. Therefore, under conditions where those mechanisms work, it can be expected that the smaller its microswimmer size, the faster its self-propulsion velocity. Because of its remarkable feature, this concept is considered to be suitable as propulsion mechanisms for future medical microrobots to move inside the human body through the vascular system, including capillaries. We have already proved the mechanisms by observing the several 10 μm/s velocity of 100 μm prototypes fabricated by the optical photolithography using several photomasks and alignment steps. However, the standard photolithography was not suitable for further miniaturization of prototypes due to its insufficient resolution. In this research, we adopted femtosecond-laser 3D microlithography for multi-materials composing of the conductive polymer composites and nonconductive polymer composite and succeeded in fabricating 10 μm prototypes. Then we demonstrated more than 100 μm/s velocity of the prototype experimentally and proved its validity of the smaller and faster feature.

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A ΔSOC-based equalization strategy applied to industry

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctaa095 ◽

2020 ◽

Author(s):

Maonan Wang ◽

Chun Chang ◽

Feng Ji

Keyword(s):

Open Circuit ◽

Battery Pack ◽

Battery Management System ◽

Battery Management ◽

Battery Cell ◽

New Strategy ◽

The Difference ◽

Relative Errors ◽

The Relationship ◽

Battery Cells

Abstract The voltage-based equalization strategy is widely used in the industry because the voltage (U) of the battery cell is very easy to obtain, but it is difficult to provide an accurate parameter for the battery management system (BMS). This study proposes a new equalization strategy, which is based on the difference between the state of charge (SOC) of any two battery cells in the battery pack, that is, a ΔSOC-based equalization strategy. The new strategy is not only as simple as the voltage-based equalization strategy, but it can also provide an accurate parameter for the BMS. Simply put, using the relationship between the open circuit voltage and the SOC of the battery pack, the proposed strategy can convert the difference between the voltage of the battery cells into ΔSOC, which renders a good performance. Additionally, the required parameters are all from the BMS, and no additional calculation is required, which makes the strategy as simple as the voltage-based balancing strategy. The four experiments show that the relative errors of ΔSOC estimated by the ΔSOC-based equalization strategy are 0.37%, 0.39%, 0.1% and 0.17%, and thereby demonstrate that the ΔSOC-based equalization strategy proposed in this study shows promise in replacing the voltage-based equalization strategy within the industry to obtain better performance.

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Activated Carbon Open Circuit Potential Shifts in Aqueous Solutions

ECS Transactions ◽

10.1149/1.2912043 ◽

2019 ◽

Vol 11 (20) ◽

pp. 19-28 ◽

Cited By ~ 1

Author(s):

Mikhail M. Goldin ◽

Gary J. Blanchard ◽

Alexander G. Volkov ◽

Mogely S. Khubutiya ◽

Vladimir A. Kolesnikov ◽

...

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Open Circuit Potential ◽

Open Circuit ◽

Potential Shifts

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Electrochemical Evaluation for Rust Preventive Properties of Rust Preventive Oils Coated on Fe-Cu-C Sintered Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.783-786.2537 ◽

2014 ◽

Vol 783-786 ◽

pp. 2537-2540 ◽

Cited By ~ 2

Author(s):

Satoshi Sunada ◽

Norio Nunomura ◽

Sayaka Hirata ◽

Naoki Nagase

Keyword(s):

Open Circuit Potential ◽

High Viscosity ◽

Open Circuit ◽

Second Step ◽

Sintered Steel ◽

Corrosive Solution ◽

The Third ◽

Low Viscosity ◽

Sintered Steels ◽

Electrochemical Evaluation

Since Fe-Cu-C sintered steels are easily rusted, they are coated with rust preventive oils. High viscosity of those rust preventive oils decrease workability, and low viscosity deteriorates rust preventive performance. Therefore, it is necessary to develop new rust preventive oils with contradictory properties of low viscosity and superior rust prevention. However, precise methodology to evaluate rust prevention ability has not been established. In this study, we developed new technique to quantitatively evaluate rust prevention ability by measuring the open circuit potential through thin corrosive solution on Fe-Cu-C sintered steels coated with a rust preventive oils. As a result, the ability for rust prevention can be measured quantitatively, and it decreases slowly over time, with repeating destruction and restoration. Furthermore, it was found that the deteriorating processes of rust prevention ability for rust prevention oils are composed of three characteristics steps respectively. That is, in the first step the great open circuit potential changes from 0V to-0.3V with repetition were observed where the excellent rust prevention ability was kept, in the second step it decreases slowly from-0.1V to-0.4V with oscillation of the small potential changes where the gradual decrease of rust prevention ability was recognized and in the third step it decreases monotonously in the lower potential than-0.4V where the rust was observed because of the remarkable deteriorating of the rust prevention ability.

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Experimental Study of Propagation Stage of Pitting Corrosion of 20Cr13 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.38.238 ◽

2008 ◽

Vol 38 ◽

pp. 238-247

Author(s):

A.D. Davydov ◽

V.S. Shaldaev

Keyword(s):

Pitting Corrosion ◽

Open Circuit Potential ◽

Corrosion Potential ◽

Ph Value ◽

Open Circuit ◽

Effect Of Temperature ◽

Pitting Potential ◽

Free Corrosion Potential ◽

External Power Source ◽

Corrosion Of Steel

The initiation and development of pitting corrosion of steel 20Cr13 in the NaCl solutions with various concentrations, temperatures, and pH values are studied under the potentiostatic conditions and at the free-corrosion potential. The pitting and repassivation potentials are determined using the method of cycling voltammetry. In spite of the fact that thus determined pitting potential is more positive than the corrosion potential (the open-circuit potential Eo.c.), the long-term experiments, which were performed at the free-corrosion potential, showed that pitting corrosion takes place without imposing a potential using an external power source. It is concluded that the probability of pitting corrosion of steel should be determined by comparing the corrosion potential (the open-circuit potential) with the repassivation potential Erp. Steel 20Cr13 is prone to the pitting corrosion, because Erp is more negative than Eo.c.. In the potentiostatic experiments, the variation of the depth and diameter of pits and their number with the time and the effect of temperature and electrode rotation on the pit propagation are studied. The results, which were obtained at the free-corrosion potential, are much less reproducible. In this case, in contrast to the potentiostatic conditions, the pit depth increased only slightly and the pit width increased to a larger extent. The effect of concentration, pH value, and temperature of NaCl solutions on the pit propagation is considered. It is concluded that the data on the development of pitting corrosion under the potentiostatic conditions can be hardly extended to the conditions of free corrosion potential.

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Maximal Oxygen Uptake and Daily Physical Activity in 7- to 12-Year-Old Boys

Pediatric Exercise Science ◽

10.1123/pes.5.4.357 ◽

1993 ◽

Vol 5 (4) ◽

pp. 357-366 ◽

Cited By ~ 5

Author(s):

Hazzaa M. Al-Hazzaa ◽

Mohammed A. Sulaiman

Keyword(s):

Physical Activity ◽

Heart Rate ◽

Oxygen Uptake ◽

Maximal Oxygen Uptake ◽

Open Circuit ◽

Daily Physical Activity ◽

Activity Level ◽

Activity Levels ◽

School Time ◽

The Relationship

The present study examined the relationship between maximal oxygen uptake (V̇O2max) and daily physical activity in a group of 7- to 12-year-old boys. V̇O2max was assessed through the incremental treadmill test using an open circuit system. Physical activity level was obtained from heart rate telemetry outside of school time for 8 hrs during weekdays and during 40 min of physical education classes. The findings indicated that the absolute value of V̇O2max increased with age, while relative to body weight it remained almost the same across age, with a mean of 48.4 ml · kg−1 · min−1. Moreover, heart rate telemetry showed that the boys spent a limited amount of time on activities that raise the heart rate to a level above 160 bpm (an average of 1.9%). In addition, V̇O2max was found to be significantly related to the percentage of time spent at activity levels at or above a heart rate of 140 bpm, but not with activity levels at or above a heart rate of 160 bpm.

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