Effect of oxygen on steel corrosion in steam-water flows at a temperature of 280�C

1970 ◽  
Vol 29 (2) ◽  
pp. 781-785 ◽  
Author(s):  
K. A. Nesmeyanova
Keyword(s):  
Steel Corrosion ◽  
Water Flows ◽  
Effect Of Oxygen

Effect of Oxygen Ions Diffusion on Steel Corrosion in Concrete

2011 ◽  
Vol 477 ◽  
pp. 398-403 ◽  
Author(s):  
Jun Ying Bai ◽  
Hong Mei Ai ◽  
Pu Guang Lu
Keyword(s):  
Diffusion Coefficient ◽  
Corrosion Rate ◽  
Steel Corrosion ◽  
Research Progress ◽  
Necessary Condition ◽  
Corrosion Mechanism ◽  
Ion Diffusion ◽  
Oxygen Ions ◽  
Testing Technology ◽  
Effect Of Oxygen

Oxygen ions are the necessary condition for steel corrosion which occurs when the steel’s passive film is destroyed. Oxygen ions diffusion directly influences steel corrosion rate. The paper, starting from the steel corrosion mechanism, summarized the testing technology and the research progress of oxygen ions diffusion coefficient, analyzed the influencing factors and studied further the effect of oxygen ions diffusion on steel corrosion in concrete. The testing technology of oxygen ion diffusion coefficient is combined with the testing method of steel corrosion rate, and the relationship between oxygen ions diffusion coefficient and steel corrosion rate are established.

A TEM study of the effect of oxygen on nanocavity formation and precipitation in rapid - solidified Fe-16Ni-9Cr stainless steels

1994 ◽  
Vol 52 ◽  
pp. 700-701
Author(s):  
S. Wisutmethangoon ◽  
T. F. Kelly ◽  
J.E. Flinn
Keyword(s):  
Stainless Steels ◽  
High Mobility ◽  
Hot Extrusion ◽  
Extrusion Ratio ◽  
Gas Atomization ◽  
Cavity Formation ◽  
Nucleation Sites ◽  
Heat Treated ◽  
Different Types ◽  
Effect Of Oxygen

Vacancies are introduced into the crystal phase during quenching of rapid solidified materials. Cavity formation occurs because of the coalescence of the vacancies into a cluster. However, because of the high mobility of vacancies at high temperature, most of them will diffuse back into the liquid phase, and some will be lost to defects such as dislocations. Oxygen is known to stabilize cavities by decreasing the surface energy through a chemisorption process. These stabilized cavities, furthermore, act as effective nucleation sites for precipitates to form during aging. Four different types of powders with different oxygen contents were prepared by gas atomization processing. The atomized powders were then consolidated by hot extrusion at 900 °C with an extrusion ratio 10,5:1. After consolidation, specimens were heat treated at 1000 °C for 1 hr followed by water quenching. Finally, the specimens were aged at 600 °C for about 800 hrs. TEM samples were prepared from the gripends of tensile specimens of both unaged and aged alloys.

Application of pure, thermostable, alkali-tolerant xylanase in bleaching of oxygen-delignified pine kraft pulp

TAPPI Journal ◽  
2015 ◽  
Vol 14 (11) ◽  
pp. 689-694
Author(s):  
QINGZHI MA ◽  
QI WANG ◽  
CHU WANG ◽  
NIANJIE FENG ◽  
HUAMIN ZHAI
Keyword(s):  
Intrinsic Viscosity ◽  
Chlorine Dioxide ◽  
High Purity ◽  
Kraft Pulp ◽  
Alkaline Media ◽  
Industrial Scale ◽  
Elemental Chlorine ◽  
Effect Of Oxygen ◽  
Alkaline Tolerant ◽  
Ecf Bleaching

The effect of oxygen (O2)-delignified pine kraft pulp pretreatment by high-purity, thermostable, and alkaline-tolerant xylanases on elemental chlorine free (ECF) bleaching of O2-delignification kraft pulp was studied. The study found that xylanase pretreatment preserved the intrinsic viscosity and yield of O2-delignified pulp while causing about 7% of delignification with high delignification selectivity. The xylanases with high purity, higher thermostability (75°C~80°C) in highly alkaline media (pH 8.0~9.5) could be applied on an industrial scale. Pulp pretreatment by the high-purity, thermostable, and alkaline tolerant xylanases could improve pulp brightness or reduce the chlorine dioxide (ClO2) consumption. In a D0ED1D2 bleaching sequence using the same amount of ClO2, the xylanase-pretreated pulp obtained a higher brightness (88.2% vs. 89.7% ISO) at the enzyme dose of 2 U/g pulp; or for the same brightness as control (88.2% ISO), the ClO2 dosage in the D0 stage was reduced by 27%, which represents a 16% savings in total ClO2 used for bleaching.

Uniform Water Flows within Rectangular Open Channels of Composite Roughness

2012 ◽  
Vol 2 (2) ◽  
pp. 137-139
Author(s):  
Demetriou J Demetriou J ◽  
◽  
Retsinis E Retsinis E
Keyword(s):  
Open Channels ◽  
Water Flows
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