Effect of oxygen electrode response on K L a measurement

1989 ◽  
Vol 6 (4) ◽  
pp. 350-353
Author(s):  
Ho Nam Chang ◽  
Dong Jin Kim ◽  
Murray Moo-Young
Keyword(s):  
Oxygen Electrode ◽  
Electrode Response ◽  
Effect Of Oxygen

A biospecific membrane sensor for the determination of sucrose

1983 ◽  
Vol 48 (3) ◽  
pp. 798-804 ◽  
Author(s):  
Lumír Macholán ◽  
Hana Konečná
Keyword(s):  
Thin Film ◽  
Hydrogen Peroxide ◽  
Steady State ◽  
Reaction Layer ◽  
Enzyme Reaction ◽  
Oxygen Electrode ◽  
Reaction Vessel ◽  
Membrane Sensor ◽  
Electrode Response

The paper describes a rapid method for the biospecific determination of sucrose using an oxygen electrode of the Clark type or a platinum disc anode, the measuring part of which is coated by a thin film of invertase, mutarotase and glucose oxidase co-crosslinked by glutardialdehyde together with serum albumin. After injecting the sample into the reaction vessel the current corresponding to the decrease of the oxygen content or to the formation of hydrogen peroxide in the enzyme reaction layer is registered. The steady state electrode response is proportional to the concentration of sucrose within the range of 0.03 to 1.5 mmol . l-1 and is attained during 1-2 minutes with a reproducibility of 3-4%.

Oxygen Inhibition of Photosynthetic Oxygen Evolution in Marine Plants

1976 ◽  
Vol 3 (1) ◽  
pp. 73 ◽  
Author(s):  
WJS Downton ◽  
DG Bishop ◽  
AWD Larkum ◽  
CB Osmond
Keyword(s):  
Oxygen Uptake ◽  
Oxygen Concentration ◽  
Sea Water ◽  
Oxygen Electrode ◽  
Photosynthetic Oxygen Evolution ◽  
Pocillopora Damicornis ◽  
Oxygen Inhibition ◽  
Rate Of Photosynthesis ◽  
Tridacna Maxima ◽  
Effect Of Oxygen

The effect of oxygen concentration on oxygen exchange in six species of the Chlorophyta, one of the Cyanophyta, one of the Rhodophyta, three of the Phaeophyta, zooxanthellae from Tridacna maxima (clam) and Pocillopora damicornis (coral), and a marine angiosperm was investigated with a polaro- graphic oxygen electrode. The rate of photosynthesis in air-saturated sea water ranged from 14 to 248 micromoles of oxygen evolved per hour per milligram of chlorophyll. Photosynthesis was inhibited by 15-85% in sea water adjusted to between 65 and 90% of oxygen saturation. A post- illumination burst of oxygen uptake was observed on darkening and the size of this burst was in- fluenced by oxygen concentration. Steady-state rates of oxygen uptake in the dark were enhanced at higher oxygen tensions. The likelihood that the dissolved oxygen content of sea water may regulate the productivity of reef communities is discussed.

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.

Sign in / Sign up

Export Citation Format

Share Document