scholarly journals ANALISIS PENGENDALIAN KOROSI PADA PERMUKAAN BASAH KAPAL-KAPAL BAJA DENGAN MENGGUNAKAN ZINK ANODA

2021 ◽  
Vol 4 ◽  
pp. 8-12
Author(s):  
Sonja T. A. Lekatompessy
Keyword(s):  
Corrosion Rate ◽  
Surface Area ◽  
Strong Influence ◽  
Current Strength ◽  
Excess Current ◽  
Seawater Corrosion ◽  
Strong Current

Zink anodes are very importantfor reducing the corrosion rate on underwater surface area of hull plates. Zink anodes are affixed to parts of the vessel that are prone to seawater corrosion. This study aims to find out how much influence the installed current has on the corrosion rate by analyzing the data on the use of zink anodes in the field and the data on the use of zink anodes as a result of calculations so that the use of strong currents installed according to the need will reduce the rate of corrosion. To see the strong influence of current on the rate of corrosion, it takes data on the corrosion rate of the last 5 years from 9 vessels and also the number of zink anodes used each year. From the graph of the results of the calculation of strong current according to the theory and the results of the use of zinc anodes on nine vessels, the results obtained it is clear that the installed current strength must meet the needs of each vessel because it will affect the decrease in corrosion rate. On vessel No.3, an excess current strength of 0.539Amp to 1,386 Amp, a decrease in corrosion rate reaching 0.0317 mm/year in the 5th year. On vessel No. 4, an excess current strength of 0.444 Amp to 1.822 Amp there is a decrease in corrosion rate reaching 0.0138 mm/year in the 5th year. On vessel No. 9, an excess strong current of 4,894 Amp to 5,793 Amp there is a decrease in corrosion rate reaching 0.0371 mm/year in the 5th year.

PENGARUH BAYANGAN TERHADAP OUTPUT TEGANGAN DAN KUAT ARUS PADA PEMBANGKIT LISTRIK TENAGA SURYA (PLTS)

ROTOR ◽  
2018 ◽  
Vol 11 (2) ◽  
pp. 47
Author(s):  
Hattu P D Edwin ◽  
Wabang A Jhon ◽  
Tuati Ambros ◽  
Palinggi Aris
Keyword(s):  
Solar Cell ◽  
Electric Current ◽  
Output Voltage ◽  
Electrical Energy ◽  
Current Strength ◽  
The Sun ◽  
Solar Panels ◽  
Shadow Area ◽  
Strong Current ◽  
Cloud Condition

Electrical energy is a very important requirement for the community, along with the development of the era and technological advances that are urgently needed, the need for electrical energy is very large, while the source of electricity that is currently being used still uses energy derived from fossil fuels. As we know that the source of energy derived from fossils is very limited, therefore other energy sources are sought or we are more familiar with renewable energy, one of which is the energy source that comes from the sun, which is better known as solar cell. The electricity from this solar cell is very dependent on sunlight which must illuminate the solar panels so that solar energy can be converted into electrical energy. The output from these solar panels is in the form of voltage and electric current. Some factors that can affect the amount of output or output voltage of electric current in PLTS is, temperature, shadow, (cloud condition, and surrounding environment), and wind speed. Therefore, the purpose of this research is to find out how much the shadow effect on the output voltage and electric current produced by PLTS. It is expected that this research can increase the knowledge of energy derived from the sun in this case the solar cell and know the effect of the shadow on the output voltage and electric current from solar panels.The results showed that there was a shadow effect on voltage reduction and current strength in the PLTS system, namely the 10% shadow area and 12.44 volt DC solar panel current and 2.54 amperage, 100% area covering the voltage output panel and the current of solar panels 12.10 volt DC and 0.22 amperage. The area of the shadow that covers the solar panel affects the output voltage and the strong current of the battery that is the area of the shadow 10% voltage and strong current battery 12.35 volt DC and 18.54 amper, 100% area cover the output panel voltage and strong current battery 11.90 volt DC and 13.85 amperes The shadow area covering the solar panels influences the output voltage and current strength of the inverter, namely the area of the shadow 10% voltage and 226.4 volt AC inverter current and 0.97 amperage, 100% covering the output voltage panel and 220.2 volt AC and 0.66 amperage current. Keywords: Electrical energy, Solar cell, Shadow (cloud condition)

scholarly journals Inhibition of Iron Corrosion in Seawater Using Rosemary Extracts (Rosmarinusofficinalis L.)

2019 ◽  
Keyword(s):  
Corrosion Rate ◽  
Environmental Protection ◽  
Organic Compounds ◽  
Inhibitory Activity ◽  
Plant Material ◽  
Corrosion Inhibitors ◽  
High Toxicity ◽  
Iron Corrosion ◽  
Leaf Extracts ◽  
Seawater Corrosion

Due to a growing awareness of environmental protection, an interest in replacing toxic corrosion inhibitors with more environmentally acceptable alternatives is also growing. Chromates, as one of the best inhibitors, have been eliminated as technically viable inhibitors because of their high toxicity, and the use of polyphosphates has diminished as they disrupt the balance in the Plantae kingdom. The emphasis is on exploration and testing of organic compounds that can be obtained from plant material. Rosemary extracts (leaf and flower) have been shown to have inhibitory activity on iron corrosion in 3% NaCl and seawater. Corrosion rate values ​​show that rosemary flower extracts are better inhibitors of corrosion than the leaf extracts and that the maximum inhibitory protection has not been achieved in the range of tested concentrations.

scholarly journals Relationships between specific surface area and pore size in electrospun polymer fibre networks

2009 ◽  
Vol 7 (45) ◽  
pp. 641-649 ◽  
Author(s):  
S. J. Eichhorn ◽  
W. W. Sampson
Keyword(s):  
Cell Proliferation ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Cross Sections ◽  
Strong Influence ◽  
Polymer Networks ◽  
Polymer Scaffolds ◽  
Polymer Fibre ◽  
Cross Sectional

From consideration of the extent of contact between fibres in electrospun polymer networks, we provide theory relating the specific surface area of the network to the characteristic dimensions of interfibre voids. We show that these properties are strongly influenced by the cross-sectional morphologies of fibres. Whereas porosity has a strong influence on pore dimensions, in the range of porosities typically obtained in real networks, its influence on specific surface area is weak. By considering reference geometries of collapsed ribbons and fibres with circular cross sections, we demonstrate that at a given network porosity, fibre parameters that increase the specific surface area reduce the characteristic dimensions of voids. The implications of the theory, mainly in the context of cell proliferation on electrospun polymer scaffolds, are discussed; the theory has relevance also to future applications of these materials in composites.

scholarly journals PENGARUH ENERGI AKTIVASI LOGAM PELAPIS TERHADAP KETEBALAN DAN LAJU KOROSI PLATING

2019 ◽  
Vol 3 (1) ◽  
Author(s):  
A. Noor Setyo HD ◽  
Sri Widodo
Keyword(s):  
Corrosion Rate ◽  
Optical Microscope ◽  
Current Strength ◽  
Nickel Layer ◽  
Chromium Layer ◽  
Chromium Plating ◽  
Nickel Chromium ◽  
Energy Gradient ◽  
Electrolyte Mixture ◽  
Electroplating Process

This study aims to study the effect of the activation energy gradient (∆G) of metals on the thickness and corrosion rate of Ni layers; Cr, and Ni-Cr. The layer is obtained through the Ni electroplating process; Cr, and Ni-Cr in carbon steel specimens using a variation of current strength of 1.25; 1.5 and 1.75 Ampere at constant stress and coating time (15 minutes). Nickel plating is obtained in the electric layer process using a watt's bath electrolyte solution in a mixture of 150 g / l NiSO4, 30 g / l NH4Cl, 30 g / l H3BO3 with a temperature of 25-35 oC, pH around 4-6, air agitation, Chromium plating using anode in the form of an alloy of Pb (lead) and Sn (antimony) rods, a solution in the form of an electrolyte mixture of 300 g / l CrO3, 3 g / l H2SO4 in working temperature of 40–55 oC, pH around 0.4 - 0.5 and air agitation. Corrosion thickness was observed using an optical microscope at 200 X magnification while the corrosion rate of observation was carried out based on the method of resistance polarization in the medium of 0.9% Sodium Chlorid Solution. The results showed that, in the same treatment, the thickness of the layer increased in increasing current strength, slower chromium than nickel layer and Nickel-Chromium layer. Sequential thickness of layers is obtained for Ni: 51, Cr: 39 layers, while corrosion rates occur at 1.75 A current in nickel layer 0.0017 mm / year; Chromium layer, 0.0077 mm /year and Nickel-Chromium layer 0.0231 mm / year

R7T7 Nuclear Waste Glass Behavior in Moist Clay: Role of the Clay Mass/Glass Surface Area Ratio

1989 ◽  
Vol 176 ◽  
Author(s):  
N. Godon ◽  
E. Vernaz
Keyword(s):  
Corrosion Rate ◽  
Surface Area ◽  
Glass Surface ◽  
Retention Factor ◽  
Distilled Water ◽  
Barrier Material ◽  
Surface Area Ratio ◽  
Corrosion Rates ◽  
Glass Corrosion

ABSTRACTR7T7 glass alteration was investigated in the presence of various moist clays. In contact with smectite 4a, selected in France as a potential engineered barrier material, the glass was significantly corroded: after 6 months the glass corrosion rate was practically the same as the initial alteration rate in double-distilled water. Substantially lower alteration was observed in contact with bentonite 6 activated by sodium carbonate.Smectite 4a consumes silicon released by glass corrosion, and thus retards the rise to high silicon concentrations in solution at which the glass corrosion rate diminishes. Glass can therefore in some cases be altered as much in moist clay as in water with high renewal rates. Other experiments with smaller quantities of smectite 4a showed that the phenomenon becomes less important in time: its duration is proportional to the ratio between the clay mass (C) and the glass surface area (SA). Comparing the results of studies at different C/SA ratios indicates that low glass corrosion rates are obtained more slowly at higher C/SA ratios.Tests with 239Pu-doped R7T7 glass also showed that the radionuclide retention factor in the alteration film at the glass surface is only 6, compared with a factor of nearly 50 in double-distilled water.

scholarly journals Variasi Konsentrasi Inhibitor Ekstrak Buah Harendong (Melastoma Affine D. Don) Pada Baja Per Daun Dengan Perlakuan Panas 300 Dan 700 °C Terhadap Laju Korosi Dalam Larutan NaCl 3%

2019 ◽  
Vol 7 (2) ◽  
pp. 187-196
Author(s):  
Dwi Kurniawan ◽  
◽  
Ediman Ginting Suka ◽  
Suprihatin Suprihatin ◽  
◽  
...  
Keyword(s):  
Crystal Structure ◽  
Heat Treatment ◽  
Weight Loss ◽  
Corrosion Rate ◽  
Surface Area ◽  
Sample Surface ◽  
Sem Analysis ◽  
Inhibitor Concentration ◽  
Fruit Extract ◽  
Eds Analysis

Research on variations in the concentration of inhibitors of harendong extract (Melastoma Affine D. Don) on steel per leaf with heat treatments 300 and 700 °C has been carried out on the corrosion rate in 3% nacl solution.The purpose of this study was to determine the efficiency of harendong fruit extract on the rate of koros in steel per leaf with heat treatment 300 and 700 °C. To determine the corrosion rate, the method of weight loss is used. The results showed that the efficiency of harendong fruit extract on the 5% inhibitor concentration at 300 °C was 90.345%. Based on the results of XRD in the sample Fe obtained with the Orthorombic crystal structure. Based on the results of SEM analysis and EDS the corroded sample surface area was reduced and fewer FeO levels in the sample were reduced. From the results of the corrosion rate and SEM and EDS analysis, it was found that the harendong fruit extract inhibitors were effective in inhibiting the corrosion rate in steel per leaf

scholarly journals SYNTHESIS OF CARBON NANOTUBES BY THE ELECTRIC ARC-DISCHARGE METHOD

2020 ◽  
Vol 5 (443) ◽  
pp. 126-133
Author(s):  
Yermagambet Bolat Toleukhanuly ◽  
◽  
Kazankapova Maira Kuttybaevna ◽  
Kassenova Zhanar Muratbekovna ◽  
Nauryzbaeva Asemay Turlangyzy ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Pore Volume ◽  
Arc Discharge ◽  
Current Strength ◽  
Electric Arc ◽  
Electric Arc Discharge ◽  
Synthesis Of Carbon Nanotubes

The paper presents the synthesis of carbon nanotubes (CNTs) by the method of electric arc-discharge. To obtain CNTs, the process of an electric arc-discharge of graphite was carried out; the current strength at a constant voltage of 50 V was 120, 150, 170, 200 A (inert medium - argon). Using the methods of electron microscopy, BET and Raman scattering, the chemical composition, specific surface area were determined, and the surface morphology of the obtained samples was studied. The results of determining the specific surface area and pore volume show that with increasing current strength, the specific surface area and specific pore volume increase from 25.450 to 159.737 m2/g and from 0.011 cm3/g to 0.068 cm3/ g, respectively. Electron microscopic images show CNT particles with a diameter of 58 to 370 nm, which are rolled into a single, seamless, cylindrical shape.

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