The damage mechanism of Alloy 690TT against Alloy 600 caused by fretting wear in room temperature pure water

Diffusion bonding was conducted on cold-worked Alloy 600. Cold-work of 50 % was applied prior to diffusion bonding in order to incite recrystallization and limit grain growth. Tensile testing was conducted at room temperature and 550 °C for evaluation of joint efficiency, while premature brittle failure at the bond-line was observed for most diffusion bonding conditions. It was found that such premature failure was related to a planar bond-line that indicated lack of grain boundary diffusion across the bonding surfaces. Additional application of post-bond heat treatments did not result in significant bond-line migration. Microstructural analyses revealed the existence of Cr-rich carbides and Ti-rich precipitates along the bond-line, which prevented bond-line migration by acting as pinning points.

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HCl Gas Sensor Coating Based on Poly(N-isopropylacrylamide) Nanoparticles Prepared from Water-Methanol Binary Solvent

Sensors ◽

10.3390/s18103283 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3283 ◽

Cited By ~ 3

Author(s):

Masanobu Matsuguchi ◽

Shinnosuke Fujii

Keyword(s):

Room Temperature ◽

Pure Water ◽

Electron Microscopic Observation ◽

Spherical Particles ◽

Binary Solvent ◽

Electron Microscopic ◽

Coated Nanoparticles ◽

Water Solvent ◽

Scanning Electron Microscopic ◽

Hcl Gas

Poly(N-isopropylacrylamide) (PNIPAM) nanoparticles formed in water-methanol binary solvent were successfully deposited on a resonator surface at room temperature by exploiting the cononsolvency effect on the phase transition of PNIPAM aqueous solutions. Scanning electron microscopic observation revealed that the nanoparticles were secondary and made up of agglomerated primary spherical particles of about 10-nm diameter, buried in the film. The magnitude of the sensor response toward HCl gas was larger than that of the nanoparticle sensor prepared from pure water solvent, and the sensitivity to 1 ppm of HCl of sensor-coated nanoparticles based on the present method was 3.3 Hz/ppm. The recovery of the sensors was less than 90% at first cycle measurement, but had improved to almost 100% at the third cycle.

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The Effect Of Hydrazine Addition On The Formation Of Oxygen Molecule By Fast Neutron Radiolysis

KnE Energy ◽

10.18502/ken.v1i1.471 ◽

2016 ◽

Vol 1 (1) ◽

Author(s):

G.R. Sunaryo

Keyword(s):

Room Temperature ◽

Pure Water ◽

Water System ◽

Calculation Model ◽

High Dose ◽

Primary Coolant ◽

Batch System ◽

Different Temperatures ◽

Oxygenated Water ◽

Deaerated Condition

Hypothetically speaking, hydrazine could suppress the oxygen formation as a major of corrosion initiator. In this work, we developed a calculation model to understand the effect of hydrazine addition toward the oxygen under PWR condition. Our great interest is to study whether this strategy would also be effectively applied in PWRs<a href="file:///C:/Users/Mohamad%20Mostafa/Desktop/Knowledge%20E/In%20Press%20Conferences/ICoNETS-2015/Source-Manuscripts/20_L05-Geni_p136-141.docx#_msocom_1">[P1]</a> . In the present work, the effect of hydrazine on suppressing the molecule oxygen under neutron irradiation is described. The simulation was done by using FACSIMILE. The variation dose applied assuming a batch system and at high dose ~104 Gy s-1. Three different temperatures were applied, which are room temperature, 250 and 300 oC at two system oxygenated water, which are aeration and deaeration. At room temperature, for deaerated condition, added hydrazine under a range of 10-6 – 10-4 M into primary coolant were not effective to suppress O2 form since the effect was similar as in the pure water system since for 10-3 M hydrazine addition, a large produce of O2 were obtained. In reverse, for deaerated condition, hydrazine concentrate about 10-3 M can suppress O2 form significantly, while hydrazine add in the range between 10-6 – 10-4 M is again confirmed to be the same as in pure water system. For high temperature, at 250 and 300 oC, the results showed that in deaerated condition, hydrazine addition can suppress O2 form proportionally to its concentration while in aerated condition, hydrazine add with concentration of 10-6 and 10-5 M were not effectively to suppress O2 form, a slightly decrease of O2 occurred due to the addition of 10-4 M hydrazine and 10-3 M of hydrazine can suppress the formation of O2 significantly. <a href="file:///C:/Users/Mohamad%20Mostafa/Desktop/Knowledge%20E/In%20Press%20Conferences/ICoNETS-2015/Source-Manuscripts/20_L05-Geni_p136-141.docx#_msocom_2">[P2]</a> <div><hr align="left" size="1" width="33%" /><div><div> <a href="file:///C:/Users/Mohamad%20Mostafa/Desktop/Knowledge%20E/In%20Press%20Conferences/ICoNETS-2015/Source-Manuscripts/20_L05-Geni_p136-141.docx#_msoanchor_1">[P1]</a>The added sentence </div></div><div><div> <a href="file:///C:/Users/Mohamad%20Mostafa/Desktop/Knowledge%20E/In%20Press%20Conferences/ICoNETS-2015/Source-Manuscripts/20_L05-Geni_p136-141.docx#_msoanchor_2">[P2]</a>The revised sentence</div></div></div>

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Preparation and Applications of Hydrophilic Nano-Carbon Particles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.832.767 ◽

2013 ◽

Vol 832 ◽

pp. 767-772 ◽

Cited By ~ 5

Author(s):

Shoichiro Ikeda ◽

Shinji Kawasaki ◽

Akinari Nobumoto ◽

Hideo Ono ◽

Shinji Ono ◽

...

Keyword(s):

Carbon Nanoparticles ◽

Room Temperature ◽

Ph Value ◽

Pure Water ◽

Solid Lubricants ◽

Cutting Fluids ◽

Carbon Particles ◽

Synthetic Graphite ◽

Nano Carbon

We have produced nanocarbon suspension in pure water, which is named as Nanocaloid®, by a simple DC electrolysis from a synthetic graphite plates as anodes and SUS plates as cathodes in purified water at room temperature. The amount of carbon nanoparticles was monitored by the conductivity and pH value of the electrolyte solution, and also by a simple gravimetric way after drying the solution. If the current density increases, the diameter of the carbon particles becomes larger and the amount of precipitates becomes also large. It takes about six weeks to obtain about 0.4 wt% carbon suspension solution under the normal electrolysis conditions. Characterization of Nanocaloid®has been conducted to show unique properties and promising epoch-making applications such as solid lubricants for non-oily cutting fluids and conductive agents for reuse of deteriorated Pb-acid batteries. The performance of nanocarbon particles in oil lubricants in addition to the preparation will be reported.

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Effect of Solvent Composition on the Critical Micelle Concentration of Cetylpyridinium Chloride in Ethanol-Water Mixed Solvent Media

Nepal Journal of Science and Technology ◽

10.3126/njst.v13i1.7446 ◽

2013 ◽

Vol 13 (1) ◽

pp. 89-93 ◽

Cited By ~ 5

Author(s):

Ajaya Bhattarai ◽

Sujit Kumar Shah ◽

Ashok Kumar Yadav

Keyword(s):

Critical Micelle Concentration ◽

Room Temperature ◽

Mixed Solvent ◽

Volume Fraction ◽

Science And Technology ◽

Pure Water ◽

Specific Conductivity ◽

Cetylpyridinium Chloride ◽

Solvent Composition ◽

Effect Of Solvent

The accurate measurement of the specific conductivity of cetylpyridinium chloride in pure water and ethanol-water mixed solvent media containing 0.10, 0.20, 0.30 and 0.40 volume fraction of ethanol at room temperature are reported. The concentrations were varied from ~ 0.005 mol l-1 to ~ 0.0002 mol l-1.The conductivity of cetylpyridinium chloride decreases with the increase in the volume fraction of ethanol. The critical micelle concentration of cetylpyridinium chloride increases with the increase in the volume fraction of ethanol. Nepal Journal of Science and Technology Vol. 13, No. 1 (2012) 89-93 DOI: http://dx.doi.org/10.3126/njst.v13i1.7446

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Sorptive Removal of Odorous Carbonyl Gases by Water

The Scientific World JOURNAL ◽

10.1100/tsw.2010.66 ◽

2010 ◽

Vol 10 ◽

pp. 535-545

Author(s):

Ehsanul Kabir ◽

Ki-Hyun Kim

Keyword(s):

Carbonyl Compounds ◽

Room Temperature ◽

Concentration Level ◽

Pure Water ◽

Water Volume ◽

Gas Stripping ◽

Removal Capacity ◽

Stripping Method ◽

Working Standards ◽

Concentration Levels

In this study, the removal capacity of deionized water was investigated against five gaseous carbonyl compounds (i.e., acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and isovaleraldehyde) by means of the gas stripping method. To determine the trapping behavior of these odorants by water, gaseous working standards prepared at three different concentration levels (i.e., for acetaldehyde around 300, 500, and 1,000 ppb) were forced through pure water contained in an impinger at room temperature. The removal efficiency of the target compounds was inspected in terms of two major variables: (1) concentration levels of gaseous standard and (2) impinger water volume (20, 50, 100, and 150 mL). Although the extent of removal was affected fairly sensitively by changes in water volume, this was not the case for standard concentration level changes. Considering the efficiency of sorption media, gas stripping with aqueous solution can be employed as an effective tool for the removal of carbonyl odorants.

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Application of a √ area -Approach for Fatigue Assessment of Cast Aluminum Alloys at Elevated Temperature

Metals ◽

10.3390/met8121033 ◽

2018 ◽

Vol 8 (12) ◽

pp. 1033 ◽

Cited By ~ 10

Author(s):

Roman Aigner ◽

Christian Garb ◽

Martin Leitner ◽

Michael Stoschka ◽

Florian Grün

Keyword(s):

Elevated Temperature ◽

Fatigue Strength ◽

Room Temperature ◽

Elevated Temperatures ◽

Damage Mechanism ◽

Cyclic Fatigue ◽

Fatigue Tests ◽

Cast Aluminum ◽

Fatigue Assessment ◽

Cast Aluminum Alloys

This paper contributes to the effect of elevated temperature on the fatigue strength of common aluminum cast alloys EN AC-46200 and EN AC-45500. The examination covers both static as well as cyclic fatigue investigations to study the damage mechanism of the as-cast and post-heat-treated alloys. The investigated fracture surfaces suggest a change in crack origin at elevated temperature of 150 ∘ C. At room temperature, most fatigue tests reveal shrinkage-based micro pores as their crack initiation, whereas large slipping areas occur at elevated temperature. Finally, a modified a r e a -based fatigue strength model for elevated temperatures is proposed. The original a r e a model was developed by Murakami and uses the square root of the projected area of fatigue fracture-initiating defects to correlate with the fatigue strength at room temperature. The adopted concept reveals a proper fit for the fatigue assessment of cast Al-Si materials at elevated temperatures; in detail, the slope of the original model according to Murakami should be decreased at higher temperatures as the spatial extent of casting imperfections becomes less dominant at elevated temperatures. This goes along with the increased long crack threshold at higher operating temperature conditions.

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