Tuning the Fe(II)/(I) formal potential of the FeN4 catalysts adsorbed on graphite electrodes to the reversible potential of the reaction for maximum activity: Hydrazine oxidation

2013 ◽  
Vol 30 ◽  
pp. 34-37 ◽  
Author(s):  
Francisco Javier Recio ◽  
Paulina Cañete ◽  
Federico Tasca ◽  
Cristian Linares-Flores ◽  
José Heráclito Zagal
Keyword(s):  
Maximum Activity ◽  
Formal Potential ◽  
Graphite Electrodes ◽  
Hydrazine Oxidation ◽  
Reversible Potential

Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

1977 ◽  
Vol 16 (01) ◽  
pp. 30-35 ◽  
Author(s):  
N. Agha ◽  
R. B. R. Persson
Keyword(s):  
Complex Formation ◽  
Significant Influence ◽  
Room Temperature ◽  
Ph Value ◽  
Maximum Activity ◽  
Reduction Step ◽  
Labelling Yield ◽  
Different Temperatures ◽  
Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

THE USE OF GLYCEROL FOR THE CRYOPRESERVATION OF INCONNU’S SPERM

2017 ◽  
pp. 117-121
Author(s):  
Amina Kumarovna Karamuldaeva ◽  
Andrey Mikhailovich Tikhomirov
Keyword(s):  
Semen Quality ◽  
Life Time ◽  
Egg Yolk ◽  
Maximum Activity ◽  
Equilibration Time ◽  
Glycerol Concentration ◽  
Scientific Center ◽  
Spawning Period ◽  
Base Solution ◽  
Academy Of Sciences

The article studies the possibility to use glycerol as cryoprotectant, instead of dimethylsulfoxide for cryopreservation of sperm of inconnu ( Stenodus leucichthys Gueldenstaedtii, 1772). Investigations were carried out from 2015 to 2016 in the laboratory of the Southern Scientific Center, Russian Academy of Sciences, on the basis of the Astrakhan State Technical University. The material collected on the Alexander sturgeon hatcheries (the Astrakhan region) in the spawning period. Native sperm of 6 male inconnu species was used as a control means. The semen quality was determined in terms of moving activity (life time) of sperm after its activation by water. As the cryoprotectant there were used: base solution - 80%, sucrose - 1.71 g/l, mannite - 0.98 g/l, yolk - 10%, dimethylsulfoxide - 10% and base solution - 87%, sucrose - 1.71% g/l, mannite - 0.98 g/l, yolk - 10%, glycerol - 3 variants: 3; 5 and 10%. In order to provide the most complete penetration of cryoprotectants into the cells there were used electrostimulation of cell membranes. Equilibration time was 5 and 15 minutes. Thawing semen was performed in a water bath at a temperature of 38-40°C. For removing protectors from cells there was chosen a saline solution (0.7% NaCl) as isotonic solution. In tests using dimethylsulfoxide life activity of sex cells was 2 times lower than in tests with glycerol: 78 and 186.2 s at the end of equilibration and 52.3 and 128.9 s after thawing. Sperm showed maximum activity under 5% glycerol concentration during equilibration - 15 min. Concentration of 3% was insufficient, concentration of 10% was excessive, as it suppressed activity of sperm. Egg yolk which coagulated together with glycerol, making difficulty for observing, had to be excluded from the composition of cryoprotectant.

Electricity Production from Dual Chambers Microbial Fuel Cell Fed with Chicken Manure-Wastewater

2015 ◽  
Vol 3 (1) ◽  
pp. 9-18
Author(s):  
Ali J. Jaeel
Keyword(s):  
Fuel Cell ◽  
Microbial Fuel Cell ◽  
Chicken Manure ◽  
Electricity Production ◽  
Anaerobic Sludge ◽  
Livestock Wastewater ◽  
Graphite Electrodes ◽  
Reliable Source ◽  
Current Densities ◽  
Resistance Value

Chicken manure wastewaters are increasingly being considered a valuable resource of organic compounds. Screened chicken manure was evaluated as a representative solid organic waste. In this study, electricity generation from livestock wastewater (chicken manure) was investigated in a continuous mediator-less horizontal flow microbial fuel cell with graphite electrodes and a selective type of membrane separating the anodic and cathodic compartments of MFC from each other. The performance of MFC was evaluated to livestock wastewater using aged anaerobic sludge. Results revealed that COD and BOD removal efficiencies were up to 88% and 82%, respectively. At an external resistance value of 150 Ω, a maximum power and current densities of 278 m.W/m2 and 683 mA/m2, respectively were obtained, hence MFC utilizing livestock wastewater would be a sustainable and reliable source of bio-energy generation .

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