Inhibition of copper corrosion in cooling seawater under flowing conditions by novel pyrophosphate

AbstractThe influence of 1H-benzotriazole, 5-methyl-1H-benzotriazole and 5-chloro-1H-benzotriazole on copper corrosion in an acidic sulphate medium was studied, as well as the influence of chloride ions on the corrosion behaviour of copper. The methods used were potentiodynamic measurements, open circuit potential and mass loss. The results show that the examined compounds possess good inhibitory properties in an acidic medium. The potentiodynamic polarisation results indicate that the degree of copper protection against corrosion depends on the concentration of Cl

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Copper Corrosion in Ultrasound Cavitation Field

The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science ◽

10.35219/mms.2021.3.06 ◽

2021 ◽

Vol 44 (3) ◽

pp. 31-35

Author(s):

Cristian Ștefan DUMITRIU ◽

Alina BĂRBULESCU

Keyword(s):

Mass Loss ◽

Statistical Methods ◽

Experimental Setup ◽

Copper Corrosion ◽

Cavitation Field ◽

Ultrasound Generator

This article contains the results of the experiments concerning the mass loss of copper in seawater, in the cavitation presence. The cavitation is produced by ultrasound in an experimental setup designed for this purpose. The models of mass loss are provided and validated by statistical methods. Gravimetric indices are computed, to compare the mass loss in different cases. Differences are noticed in the mass-loss trend at different power of the ultrasound generator.

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Characterization of Vapor Phase Copper Corrosion Products Using Electrochemical Methods

ECS Transactions ◽

10.1149/1.3046633 ◽

2019 ◽

Vol 15 (1) ◽

pp. 193-201

Author(s):

David M. Bastidas ◽

Emilio Cano ◽

Victoria M. La Iglesia ◽

Jose M. Bastidas

Keyword(s):

Vapor Phase ◽

Corrosion Products ◽

Electrochemical Methods ◽

Copper Corrosion

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Imaging molecules adsorbed onto electrodes under potential control by scanning probe microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086180 ◽

1991 ◽

Vol 49 ◽

pp. 376-377 ◽

Cited By ~ 1

Author(s):

N.J. Tao ◽

J.A. DeRose ◽

P.I. Oden ◽

S.M. Lindsay

Keyword(s):

Surface Charge ◽

Environmental Effects ◽

Scanning Probe Microscopy ◽

Statistical Significance ◽

Electrochemical Methods ◽

Surface Structures ◽

Scanning Probe ◽

Potential Control ◽

Afm Imaging ◽

Special Circumstances

Clemmer and Beebe have pointed out that surface structures on graphite substrates can be misinterpreted as biopolymer images in STM experiments. We have been using electrochemical methods to react DNA fragments onto gold electrodes for STM and AFM imaging. The adsorbates produced in this way are only homogeneous in special circumstances. Searching an inhomogeneous substrate for ‘desired’ images limits the value of the data. Here, we report on a reversible method for imaging adsorbates. The molecules can be lifted onto and off the substrate during imaging. This leaves no doubt about the validity or statistical significance of the images. Furthermore, environmental effects (such as changes in electrolyte or surface charge) can be investigated easily.

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Water accumulation as a function of temperature on specimens in an electron microscope cold stage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142219 ◽

1986 ◽

Vol 44 ◽

pp. 114-115 ◽

Cited By ~ 2

Author(s):

M.K. Lamvik ◽

D.A. Kopf ◽

S.D. Davilla ◽

J.D. Robertson

Keyword(s):

Electron Microscope ◽

Mass Loss ◽

Liquid Helium ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Liquid Helium Temperature ◽

Helium Temperature ◽

Cold Stage ◽

Water Accumulation ◽

Better Than

Last year we reported1 that there is a striking reduction in the rate of mass loss when a specimen is observed at liquid helium temperature. It is important to determine whether liquid helium temperature is significantly better than liquid nitrogen temperature. This requires a good understanding of mass loss effects in cold stages around 100K.

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Electron Beam-Induced Mass Loss in Freeze-Dried Tissue and Protein Samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011917x ◽

1985 ◽

Vol 43 ◽

pp. 470-471

Author(s):

M.E. Cantino ◽

M.K. Goddard ◽

L.E. Wilkinson ◽

D.E. Johnson

Keyword(s):

Electron Beam ◽

Salivary Gland ◽

Mass Loss ◽

Counting Rate ◽

Dose Dependence ◽

X Ray ◽

Large Samples ◽

Freeze Dried ◽

Muscle Homogenate ◽

Large Muscle

Quantification in biological x-ray microanalysis depends on accurate evaluation of mass loss. Although several studies have addressed the problem of electron beam induced mass loss from organic samples (eg., 1,2). uncertainty persists as to the dose dependence, the extent of loss, the elemental constituents affected, and the variation in loss for different materials and tissues. in the work described here, we used x-ray counting rate changes to measure mass loss in albumin (used as a quantification standard), salivary gland, and muscle.In order to measure mass loss at low doses (10-4 coul/cm2 ) large samples were needed. While freeze-dried salivary gland sections of the required dimensions were available, muscle sections of this size were difficult to obtain. To simulate large muscle sections, frog or rat muscle homogenate was injected between formvar films which were then stretched over slot grids and freeze-dried. Albumin samples were prepared by a similar procedure. using a solution of bovine serum albumin in water. Samples were irradiated in the STEM mode of a JEOL 100C.

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TEM study of a biofilm on copper corrosion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163563 ◽

1996 ◽

Vol 54 ◽

pp. 220-221

Author(s):

W. A. Chiou ◽

N. Kohyama ◽

B. Little ◽

P. Wagner ◽

M. Meshii

Keyword(s):

Marine Bacterium ◽

Culture Medium ◽

Copper Alloys ◽

Pure Copper ◽

Localized Corrosion ◽

Natural Seawater ◽

Copper Corrosion ◽

New Approach ◽

The Past ◽

Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

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Elemental mass loss in silicate minerals during x-ray analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177155 ◽

1990 ◽

Vol 48 (4) ◽

pp. 804-805

Author(s):

P.E. Champness ◽

R.W. Devenish

Keyword(s):

Mass Loss ◽

Current Density ◽

Damage Mechanism ◽

Beam Current ◽

Single Chain ◽

Plagioclase Feldspar ◽

X Ray ◽

Alkali Ions ◽

Structural Order ◽

Sheet Silicate

It has long been recognised that silicates can suffer extensive beam damage in electron-beam instruments. The predominant damage mechanism is radiolysis. For instance, damage in quartz, SiO2, results in loss of structural order without mass loss whereas feldspars (framework silicates containing Ca, Na, K) suffer loss of structural order with accompanying mass loss. In the latter case, the alkali ions, particularly Na, are found to migrate away from the area of the beam. The aim of the present study was to investigate the loss of various elements from the common silicate structures during electron irradiation at 100 kV over a range of current densities of 104 - 109 A m−2. (The current density is defined in terms of 50% of total current in the FWHM probe). The silicates so far ivestigated are:- olivine [(Mg, Fe)SiO4], a structure that has isolated Si-O tetrahedra, garnet [(Mg, Ca, Fe)3Al2Si3AO12 another silicate with isolated tetrahedra, pyroxene [-Ca(Mg, Fe)Si2O6 a single-chain silicate; mica [margarite, -Ca2Al4Si4Al4O2O(OH)4], a sheet silicate, and plagioclase feldspar [-NaCaAl3Si5O16]. Ion- thinned samples of each mineral were examined in a VG Microscopes UHV HB501 field- emission STEM. The beam current used was typically - 0.5 nA and the current density was varied by defocussing the electron probe. Energy-dispersive X-ray spectra were collected every 10 seconds for a total of 200 seconds using a Link Systems windowless detector. The thickness of the samples in the area of analysis was normally 50-150 nm.

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