scholarly journals On question of using zinc electrodes for monitoring cathodic protection of ships and vessels

2021 ◽  
Vol 2021 (2) ◽  
pp. 16-23
Author(s):  
Dmitry Pavlovich Yastrebov ◽  
Dmitry Vladimirovich Shunkin ◽  
Alexey Olegovich Rogozhnikov ◽  
Gleb Valerievich Kuznetsov
Keyword(s):  
Silver Chloride ◽  
Control Point ◽  
Reference Electrode ◽  
Time Interval ◽  
Regulatory Requirements ◽  
Reference Electrodes ◽  
Regulatory Documents ◽  
Protection Systems ◽  
Parallel Control

The article focuses on the importance of organizing the ship operators training, who control the operation of systems protecting the sea vessels from corrosion. There are presented the results of a scientific research - control of the operation of the tread protection system of the steel hull of an auxiliary marine vessel (floating workshop PM-15), which is in a long-term standby mode. The potential difference between the ship's hull and two reference electrodes was measured at a given control point. The control measurements have been carried out using the reference electrodes: silver chloride reference electrode recommended for use by regulatory documents and zinc reference electrodes (not recommended by regulatory documents for sea vessels). There have been made 50 parallel control measurements. The time interval between parallel measurements was 5 seconds. Control measurements were performed within 5 days from 07.02.2020 to 07.14.2020. The accuracy of the control measurements was assessed in accordance with regulatory requirements. It has been stated that both reference electrodes provide high accuracy of control measurements; the results of control carried out with the help of zinc reference electrodes are highly stable. It has been inferred that zinc reference electrodes can be used on Russian ships to control the tread protection of the ship's hull and can be recommended for using by ship crews for training ship operators of ship corrosion protection systems.

scholarly journals Selection of electrodes for monitoring protection systems of ships’ steel hulls and machinery

2019 ◽  
Vol 2019 (4) ◽  
pp. 39-45
Author(s):  
Дмитрий Ястребов ◽  
Dmitry Yastrebov ◽  
Олег Белов ◽  
Oleg Belov ◽  
Владимир Швецов ◽  
...  
Keyword(s):  
Silver Chloride ◽  
Control Point ◽  
Reference Electrode ◽  
Time Interval ◽  
Strong Impact ◽  
Ship Structures ◽  
Control Electrode ◽  
Accuracy Of Measurements ◽  
Protection Systems ◽  
House Design

The article considers the problems of ship structures exposed to adverse conditions, which contribute to the failure of important mechanisms and reduce the service life of steel parts of machines. One of the most important reasons for the ship structures wear is corrosion. The experience of choosing the electrodes to control the sacrificial protection systems on board ships is presented. There are presented the results of measuring the potential of the hull of the boat ROOM 52-22 at a given control point, using a multimeter MASTECH MY 62 and two control electrodes. The first control electrode is of in-house design; it was made of electric carbon product for electric machines. A standard portable silver chloride reference electrode was used as a second electrode. Both electrodes have been in operation for 3 years. The vessel under consideration was in a long-term parking mode. Control measurements were performed from 23.05 - 07.07.2019, while monitoring the potential of the hull three times a day using several parallel measurements. The time interval between parallel potential measurements made ≈ 5 seconds. The potential of the hull was measured by a specially trained operator. The accuracy of measurements was estimated using the coefficient of variation. Analysis of the studies justified that the accuracy of the control results of the protective anticorrosion systems on ships depends on the choice of the type of control electrode. It has been found that the efficiency of the silver chloride electrode has a strong impact on its operation life. The results of full-scale corrosion studies can be used by ship crews to justify the selection of control electrodes.

scholarly journals To problem of using aluminum electrodes to maintain corrosion protection of steel hulls of ships and vessels

2021 ◽  
Vol 2021 (3) ◽  
pp. 23-32
Author(s):  
Dmitry Pavlovich Yastrebov ◽  
Oleg Aleksandrovich Belov ◽  
Vladimir Alekseevich Shvetsov ◽  
Andrey Pavlovich Ushakevich ◽  
Gleb Valerievich Kuznetsov ◽  
...  
Keyword(s):  
Silver Chloride ◽  
Control Point ◽  
Reference Electrode ◽  
Time Interval ◽  
Aluminum Electrode ◽  
Test Results ◽  
Reference Electrodes ◽  
Measurement Results ◽  
Clamping Device ◽  
Complex Methods

The article highlights the test results of a non-standard reference electrode made of a stripped of insulation strand of aluminum wiring, which were conducted on board an auxiliary marine vessel PM-15. The potential of the ship’s hull was measured at the same control point using three reference electrodes: silver chloride electrode No. 1; aluminum electrode No. 2; aluminum electrode No. 3. The vessel’s hull potential was measured over five days. All three reference electrodes were used daily. With the help of each electrode, fifty parallel measurements of the potential of the ship’s hull were carried out with a time interval between measurements of 5 seconds. To assess the accuracy of the measurement results, they were processed statistically. The factors that must be taken into account in the development of technologies for manufacturing non-standard reference electrodes are listed: using available inexpensive materials; avoiding expensive equipment in manufacturing the reference electrode; eliminating complex methods of storage of reference electrodes on ships. There has been given a diagram of measuring electrical circuits including the steel hull, a bulwark, a multimeter, a clamping device, switches, a silver chloride reference electrode, aluminum wires, etc. The results of the study can be used on sea-going vessels to organize the control of the protective effect of the hulls of ships and vessels in the absence of standard reference electrodes.

scholarly journals On problem of using copper electrodes to maintain protection against corrosion of steel hulls of ships and vessels

2021 ◽  
Vol 2021 (4) ◽  
pp. 43-51
Author(s):  
Dmitry Pavlovich Yastrebov
Keyword(s):  
Corrosion Protection ◽  
Silver Chloride ◽  
Reference Electrode ◽  
Offshore Structures ◽  
Time Interval ◽  
Technical Equipment ◽  
Reference Electrodes ◽  
Technical Problems ◽  
Copper Electrodes ◽  
Silver Chloride Reference Electrode

The paper focuses on the reasons for the lack of proper control of the operation of the electrochemical protective systems of sea vessels, such as the absence of convenient technical equipment, primarily the reference electrodes, as well as the imperfection of the silver chloride reference electrode. There is considered the approach to the development of easy-to-use reference electrodes. A standard silver chloride reference electrode was used as the first electrode; experimental electrodes made of a copper wire strand stripped of insulation were used as the second and third electrodes. The experimental vessel is docked in the commercial port of Petropavlovsk-Kamchatsky. The corrosion protection of the ship’s hull was evaluated by measuring the potentials between the metal hull and the reference electrode at a given point. The measurements were performed at a time interval from 06/10/2021 to 06/18/2021, evaluating the control of the hull corrosion protection was made by taking 50 successive measurements, which were entered into the control tables. It has been stated that the results of ship’s hull sacrificial protection control by using experimental copper electrodes from cabling comply with the regulatory requirements. The ship’s crew didn’t have any financial, organizational or technical problems, which could usually arise from the operation of standard silver chloride reference electrodes. It has been inferred that using regulated and non-regulated electrodes in the organization of corrosion control on ships and metal offshore structures is possible.

scholarly journals Problem of using electrodes made of shipbuilding steel to protect ship hull from corrosion

2020 ◽  
Vol 2020 (2) ◽  
pp. 15-21
Author(s):  
Dmitry Pavlovich Yastrebov ◽  
Oleg Aleksandrovich Belov ◽  
Vladimir Alekseevich Shvetsov ◽  
Bogdan Vladimirovich Tarabanov ◽  
Sergey Anatolevich Zaitsev
Keyword(s):  
Steel Plate ◽  
Control Point ◽  
Electrical Measuring ◽  
Ship Hull ◽  
Time Interval ◽  
Electrochemical Protection ◽  
Measuring Device ◽  
Corrosion Tests ◽  
Protection Systems ◽  
Parallel Measurements

The article discusses the problem of corrosion that causes significant damage to the ship structures and mechanisms, reducing their service life. The experience of using different electrodes to control the electrochemical protection systems of steel hulls of auxiliary vessels is presented. The results of corrosion tests of PM-15 ship hull are presented, which included measurements of the hull potential at a given control point, using an electrical measuring device and two control electrodes. As the first electrode used an electric carbon product for electric machines. A ship hull steel plate was used as the second electrode. The investigated vessel stayed at the pier for a long time. Corrosion tests were carried out in the period within 10.10.2019-16.10.2019. The ship hull potential at the control point was controlled using 50 parallel measurements. Parallel measurements were performed with a specified time interval of 5 sec. between them. A qualified operator has been trained to perform corrosion studies. The accuracy of the measurements was determined on the basis of current regulatory documents. The test results show that the reliability of the control of electrochemical protection systems of the hull primarily depends on the type of electrode used. It has been demonstrated that the metrological characteristics of the results of control measurements depend on the period of using a steel plate. The results of scientific research help to select the right elements of the system of monitoring the effectiveness of electrochemical protection of the ships and ship crews.

Protection of buildings and structures against progressive collapse within the framework of legislative and regulatory requirements

2019 ◽  
pp. 46-54 ◽  
Keyword(s):  
Progressive Collapse ◽  
Professional Community ◽  
Regulatory Requirements ◽  
Technical Regulation ◽  
Regulatory Documents ◽  
Common Position ◽  
Local Destruction

At present, the current legislative and regulatory documents do not contain a clear and unambiguous answer to the question, what buildings and structures should be designed resistant to progressive collapse. In this regard, the analysis of the legal and regulatory requirements of the need for calculations to prevent the progressive collapse of buildings and structures due to hypothetical or suspected local destruction is presented. The main legislative requirements of technical regulation in the field of ensuring the mechanical safety of buildings and structures, as well as the requirements of regulatory documents regarding the design of the protection of building and structures against progressive collapse are considered. The analysis of the fundamental principles features of the calculation for the structural protection against progressive collapse is given. Some issues discussed by the professional community in the direction of possible ways of solving the actual problems of the presented problem are considered. The conclusion is made about the need for further dialogue of the professional community on the development of a common position on the protection of buildings and structures from progressive collapse, which should be reflected in the legislative and regulatory requirements.

Facile and Fast Detection of Genistein in Derris scandens by Square Wave Voltammetry using a Cobalt(II) Phthalocyanine-Modified Screen-Printed Electrochemical Sensor

2020 ◽  
Vol 16 (3) ◽  
pp. 341-348
Author(s):  
Surinya Traipop ◽  
Suchada Chuanuwatanakul ◽  
Orawon Chailapakul ◽  
Eakkasit Punrat
Keyword(s):  
Electrochemical Sensor ◽  
Square Wave Voltammetry ◽  
Silver Chloride ◽  
Reference Electrode ◽  
High Sensitivity ◽  
Plastic Substrate ◽  
Fast Analysis ◽  
Square Wave ◽  
Wave Voltammetry ◽  
Screen Printed

Background: Recently, Derris scandens, a Thai herbal medicine with anti-inflammatory activity, is widely used as beverage and supplementary food. When the traditional medicine is a choice for health therapy, the simple and reliable equipment is required to control the suitable consuming amount of the active component. Objective: To develop the electrochemical sensor for genistein determination in Derris scandens with high sensitivity and rapid operation. Methods: An in-house screen-printed electrochemical sensor consisting of a three-electrode system was developed for genistein determination. A silver/silver chloride (Ag/AgCl) reference electrode, a carbon counter electrode and a carbon working electrode were prepared on a 0.3-mm-thick plastic substrate by the screen-printing technique using conductive ink. The dimensions of each sensor were 2.5×1.0 cm. Only 50 µL of sample solution was required on this device for the determination of genistein concentration by rapid response square wave voltammetry. Results: The oxidation peak of genistein appeared with good response in acidic media at a peak potential of 0.6 V. Moreover, the signal was enhanced by modifying the conductive carbon ink with cobalt( II) phthalocyanine. Under the optimized conditions, the linear range was found to be 2.5-150 µM and the detection limit was 1.5 µM. Moreover, the small volume extraction was successfully developed without any further pre-concentration. This proposed method was applied to determine genistein in Derris scandens with satisfying results. Conclusion: The proposed method is promising as an alternative method for genistein determination with facile and fast analysis.

scholarly journals A Novel Highly Durable Carbon/Silver/Silver Chloride Composite Electrode for High-Definition Transcranial Direct Current Stimulation

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1962
Author(s):  
Lingjun Li ◽  
Guangli Li ◽  
Yuliang Cao ◽  
Yvonne Yanwen Duan
Keyword(s):  
Service Life ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Silver Chloride ◽  
Cycling Performance ◽  
High Definition ◽  
Silver Silver ◽  
Sintered Ag ◽  
Silver Silver Chloride

High-definition transcranial direct current stimulation (HD-tDCS) is a promising non-invasive neuromodulation technique, which has been widely used in the clinical intervention and treatment of neurological or psychiatric disorders. Sintered Ag/AgCl electrode has become a preferred candidate for HD-tDCS, but its service life is very short, especially for long-term anodal stimulation. To address this issue, a novel highly durable conductive carbon/silver/silver chloride composite (C/Ag/AgCl) electrode was fabricated by a facile cold rolling method. The important parameters were systematically optimized, including the conductive enhancer, the particle size of Ag powder, the C:Ag:PTFE ratio, the saline concentration, and the active substance loading. The CNT/Ag/AgCl-721 electrode demonstrated excellent specific capacity and cycling performance. Both constant current anodal polarization and simulated tDCS measurement demonstrated that the service life of the CNT/Ag/AgCl-721 electrodes was 15-16 times of that of sintered Ag/AgCl electrodes. The much longer service life can be attributed to the formation of the three-dimensional interpenetrating conductive network with CNT doping, which can maintain a good conductivity and cycling performance even if excessive non-conductive AgCl is accumulated on the surface during long-term anodal stimulation. Considering their low cost, long service life, and good skin tolerance, the proposed CNT/Ag/AgCl electrodes have shown promising application prospects in HD-tDCS, especially for daily life scenarios.

scholarly journals A Novel Deep Learning Approach for Machinery Prognostics Based on Time Windows

2019 ◽  
Vol 9 (22) ◽  
pp. 4813 ◽  
Author(s):  
Hanbo Yang ◽  
Fei Zhao ◽  
Gedong Jiang ◽  
Zheng Sun ◽  
Xuesong Mei
Keyword(s):  
Time Windows ◽  
Remaining Useful Life ◽  
Sensor Data ◽  
Time Interval ◽  
Kernel Module ◽  
Initial Stage ◽  
Research Task ◽  
Consecutive Time ◽  
Useful Life

Remaining useful life (RUL) prediction is a challenging research task in prognostics and receives extensive attention from academia to industry. This paper proposes a novel deep convolutional neural network (CNN) for RUL prediction. Unlike health indicator-based methods which require the long-term tracking of sensor data from the initial stage, the proposed network aims to utilize data from consecutive time samples at any time interval for RUL prediction. Additionally, a new kernel module for prognostics is designed where the kernels are selected automatically, which can further enhance the feature extraction ability of the network. The effectiveness of the proposed network is validated using the C-MAPSS dataset for aircraft engines provided by NASA. Compared with the state-of-the-art results on the same dataset, the prediction results demonstrate the superiority of the proposed network.

scholarly journals Time Interval to Biochemical Failure as a Surrogate End Point in Locally Advanced Prostate Cancer: Analysis of Randomized Trial NRG/RTOG 9202

2019 ◽  
Vol 37 (3) ◽  
pp. 213-221 ◽  
Author(s):  
James J. Dignam ◽  
Daniel A. Hamstra ◽  
Herbert Lepor ◽  
David Grignon ◽  
Harmar Brereton ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Randomized Trial ◽  
Locally Advanced ◽  
Biochemical Failure ◽  
Mediating Effect ◽  
Time Interval ◽  
Short Term ◽  
End Points ◽  
End Point

Background In prostate cancer, end points that reliably portend prognosis and treatment benefit (surrogate end points) can accelerate therapy development. Although surrogate end point candidates have been evaluated in the context of radiotherapy and short-term androgen deprivation (AD), potential surrogates under long-term (24 month) AD, a proven therapy in high-risk localized disease, have not been investigated. Materials and Methods In the NRG/RTOG 9202 randomized trial (N = 1,520) of short-term AD (4 months) versus long-term AD (LTAD; 28 months), the time interval free of biochemical failure (IBF) was evaluated in relation to clinical end points of prostate cancer–specific survival (PCSS) and overall survival (OS). Survival modeling and landmark analysis methods were applied to evaluate LTAD benefit on IBF and clinical end points, association between IBF and clinical end points, and the mediating effect of IBF on LTAD clinical end point benefits. Results LTAD was superior to short-term AD for both biochemical failure (BF) and the clinical end points. Men remaining free of BF for 3 years had relative risk reductions of 39% for OS and 73% for PCSS. Accounting for 3-year IBF status reduced the LTAD OS benefit from 12% (hazard ratio [HR], 0.88; 95% CI, 0.79 to 0.98) to 6% (HR, 0.94; 95% CI, 0.83 to 1.07). For PCSS, the LTAD benefit was reduced from 30% (HR, 0.70; 95% CI, 0.52 to 0.82) to 6% (HR, 0.94; 95% CI, 0.72 to 1.22). Among men with BF, by 3 years, 50% of subsequent deaths were attributed to prostate cancer, compared with 19% among men free of BF through 3 years. Conclusion The IBF satisfied surrogacy criteria and identified the benefit of LTAD on disease-specific survival and OS. The IBF may serve as a valid end point in clinical trials and may also aid in risk monitoring after initial treatment.

scholarly journals Long-Term Observations of Beach Variability at Hasaki, Japan

2020 ◽  
Vol 8 (11) ◽  
pp. 871
Author(s):  
Masayuki Banno ◽  
Satoshi Nakamura ◽  
Taichi Kosako ◽  
Yasuyuki Nakagawa ◽  
Shin-ichi Yanagishima ◽  
...  
Keyword(s):  
Morphological Change ◽  
High Frequency ◽  
Climate Changes ◽  
Wave Climate ◽  
Time Interval ◽  
Observation Data ◽  
Beach Profile ◽  
Water Level Variations ◽  
Monthly Variations

Long-term beach observation data for several decades are essential to validate beach morphodynamic models that are used to predict coastal responses to sea-level rise and wave climate changes. At the Hasaki coast, Japan, the beach profile has been measured for 34 years at a daily to weekly time interval. This beach morphological dataset is one of the longest and most high-frequency measurements of the beach morphological change worldwide. The profile data, with more than 6800 records, reflect short- to long-term beach morphological change, showing coastal dune development, foreshore morphological change and longshore bar movement. We investigated the temporal beach variability from the decadal and monthly variations in elevation. Extremely high waves and tidal anomalies from an extratropical cyclone caused a significant change in the long-term bar behavior and foreshore slope. The berm and bar variability were also affected by seasonal wave and water level variations. The variabilities identified here from the long-term observations contribute to our understanding of various coastal phenomena.

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