Inhibiting effects of imidazole on copper corrosion in 1 M HNO3 solution

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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Root Cause Analyses of Metal Bridging for Copper Damascene Process

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0283 ◽

2005 ◽

Author(s):

Z. G. Song ◽

S. P. Neo ◽

S. K. Loh ◽

C. K. Oh

Keyword(s):

Failure Mechanisms ◽

Copper Corrosion ◽

Microelectronic Device ◽

Root Cause ◽

Damascene Process ◽

New Process ◽

Copper Cmp

Abstract New process will introduce new failure mechanisms during microelectronic device manufacturing. Even if the same defect, its root causes can be different for different processes. For aluminum(Al)-tungsten(W) metallization, the root cause of metal bridging is quite simple and mostly it is blocked etch or under-etch. But, for copper damascene process, the root causes of metal bridging are complicated. This paper has discussed the various root causes of metal bridging for copper damascene process, such as those related to litho-etch issue, copper CMP issue, copper corrosion issue and so on.

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Water treatment to reduce internal corrosion in the drinking water distribution system in Oslo

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0056 ◽

2001 ◽

Vol 1 (3) ◽

pp. 91-96 ◽

Cited By ~ 1

Author(s):

L.J. Hem ◽

E.A. Vik ◽

A. Bjørnson-Langen

Keyword(s):

Water Treatment ◽

Corrosion Rate ◽

Distribution System ◽

Water Distribution ◽

Treatment Plant ◽

Water Treatment Plant ◽

Corrosion Monitoring ◽

Copper Corrosion ◽

Iron Corrosion ◽

Internal Corrosion

In 1995 the new Skullerud water treatment plant was put into operation. The new water treatment includes colour removal and corrosion control with an increase of pH, alkalinity and calcium concentration in addition to the old treatment, which included straining and chlorination only. Comparative measurements of internal corrosion were conducted before and after the installation of the new treatment plant. The effect of the new water treatment on the internal corrosion was approximately a 20% reduction in iron corrosion and a 70% reduction in copper corrosion. The heavy metals content in standing water was reduced by approximately 90%. A separate internal corrosion monitoring programme was conducted, studying the effects of other water qualities on the internal corrosion rate. Corrosion coupons were exposed to the different water qualities for nine months. The results showed that the best protection of iron was achieved with water supersaturated with calcium carbonate. Neither a high content of free carbon dioxide or the use of the corrosion inhibitor sodium silicate significantly reduced the iron corrosion rate compared to the present treated water quality. The copper corrosion rate was mainly related to the pH in the water.

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Tailoring Properties of Resol Resin-Derived Spherical Carbons for Adsorption of Phenol from Aqueous Solution

Molecules ◽

10.3390/molecules26061736 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1736

Author(s):

Karol Sidor ◽

Tomasz Berniak ◽

Piotr Łątka ◽

Anna Rokicińska ◽

Marek Michalik ◽

...

Keyword(s):

Surface Composition ◽

Micropore Volume ◽

Gaseous Ammonia ◽

Poly Vinyl Alcohol ◽

Clear Correlation ◽

Hno3 Solution ◽

Synthesis Conditions ◽

Adsorption Of Nitrogen ◽

Oxygen Groups ◽

Size Of Particles

The polycondensation of resorcinol and formaldehyde in a water–ethanol mixture using the adapted Stöber method was used to obtain resol resins. An optimization of synthesis conditions and the use of an appropriate stabilizer (e.g., poly(vinyl alcohol)) resulted in spherical grains. The resins were carbonized in the temperature range of 600–1050 °C and then chemically activated in an aqueous HNO3 solution, gaseous ammonia, or by an oxidation–reduction cycle (soaking in a HNO3 solution followed by treatment with NH3). The obtained carbons were characterized by XRD, the low-temperature adsorption of nitrogen, SEM, TGA, and XPS in order to determine degree of graphitization, porosity, shape and size of particles, and surface composition, respectively. Finally, the materials were tested in phenol adsorption. The pseudo-second order model perfectly described the adsorption kinetics. A clear correlation between the micropore volume and the adsorption capacity was found. The content of graphite domains also had a positive effect on the adsorption properties. On the other hand, the presence of heteroatoms, especially oxygen groups, resulted in the clogging of the pores and a decrease in the amount of adsorbed phenol.

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Electrospun Nanosystems Based on PHBV and ZnO for Ecological Food Packaging

Polymers ◽

10.3390/polym13132123 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2123

Author(s):

Maria Râpă ◽

Maria Stefan ◽

Paula Popa ◽

Dana Toloman ◽

Cristian Leostean ◽

...

Keyword(s):

Food Packaging ◽

Spin Trapping ◽

X Ray Diffraction ◽

Paramagnetic Resonance ◽

Hno3 Solution ◽

X Ray ◽

Trapping Method ◽

Ft Ir ◽

Doped Zno ◽

Electron Paramagnetic

The electrospun nanosystems containing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and 1 wt% Fe doped ZnO nanoparticles (NPs) (with the content of dopant in the range of 0–1 wt% Fe) deposited onto polylactic acid (PLA) film were prepared for food packaging application. They were investigated by scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), antimicrobial analysis, and X-ray photoelectron spectrometry (XPS) techniques. Migration studies conducted in acetic acid 3% (wt/wt) and ethanol 10% (v/v) food simulants as well as by the use of treated ashes with 3% HNO3 solution reveal that the migration of Zn and Fe falls into the specific limits imposed by the legislation in force. Results indicated that the PLA/PHBV/ZnO:Fex electrospun nanosystems exhibit excellent antibacterial activity against the Pseudomonas aeruginosa (ATCC-27853) due to the generation of a larger amount of perhydroxyl (˙OOH) radicals as assessed using electron paramagnetic resonance (EPR) spectroscopy coupled with a spin trapping method.

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