THE LIMITING CONDUCTANCE OF POTASSIUM IODATE AND OF IODATE ION AT 25.00 °C

1958 ◽  
Vol 36 (9) ◽  
pp. 1277-1279 ◽  
Author(s):  
A. N. Campbell ◽  
E. Bock
Keyword(s):  
Experimental Technique ◽  
Potassium Iodate ◽  
Equivalent Conductance ◽  
Ionic Conductances ◽  
Iodate Ions

Measurements have been made of the equivalent conductance of solutions of potassium iodate, at 25.00 °C at concentrations ranging from 0.8 × 10−4 to 16 × 10−4 N. From this the limiting equivalent conductance of potassium iodate is found to be 114.41 mhos and that of iodate ion 40.91 mhos. The experimental technique is described. The ionic conductances of chlorate, bromate, and iodate ions are compared.

Transference numbers and solvation studies in n-butanol

1984 ◽  
Vol 62 (2) ◽  
pp. 303-305 ◽  
Author(s):  
J. S. Banait ◽  
K. S. Sidhu ◽  
J. S. Walia
Keyword(s):  
Tetrabutylammonium Bromide ◽  
Transference Number ◽  
Transference Numbers ◽  
Ionic Radii ◽  
Equivalent Conductance ◽  
Solvation Numbers ◽  
Tetrabutylammonium Ion ◽  
Ionic Conductances ◽  
Bromide Ions

Transference numbers of tetrabutylammonium bromide have been measured in n-butanol at 25 °C in the concentration range 5.79 − 12.86 × 10−2 mol dm−3. The variation of transference number with concentration is negligible. The limiting transference number of tetrabutylammonium ion has been determined by the Longsworth method. Combining the limiting transference number and limiting equivalent conductance of this salt, limiting ionic conductances of tetrabutylammonium and bromide ions have been found to be 8.05 and 8.02 ohm−1 cm2 mol−1, respectively. From these values limiting ionic conductances of other univalent ions, effective ionic radii and solvation numbers have been computed. The solvation numbers of anions have been found to be more than those of cations which shows the protic nature of this solvent.

Morphological Observations on the Granule Types in Rabbit Extra-Adrenal Chromaffin Cells.

1975 ◽  
Vol 33 ◽  
pp. 318-319
Author(s):  
Joe A. Mascorro ◽  
Robert D. Yates
Keyword(s):  
Chromaffin Cells ◽  
Sodium Phosphate ◽  
Ganglion Cells ◽  
Ultrastructural Level ◽  
Osmic Acid ◽  
Adrenal Chromaffin Cells ◽  
Potassium Iodate ◽  
Perfusion Fluid ◽  
New Zealand White Rabbits ◽  
Adrenal Chromaffin

Extra-adrenal chromaffin organs (abdominal paraganglia) constitute rich sources of catecholamines. It is believed that these bodies contain norepinephrine exclusively. However, the present workers recently observed epinephrine type granules in para- ganglion cells. This report investigates catecholamine containing granules in rabbit paraganglia at the ultrastructural level.New Zealand white rabbits (150-170 grams) were anesthetized with 50 mg/kg Nembutal (IP) and perfused with 3% glutaraldehyde buffered with 0.2M sodium phosphate, pH 7.3. The retroperitoneal tissue blocks were removed and placed in perfusion fluid for 4 hours. The abdominal paraganglia were dissected from the blocks, diced, washed in phosphate buffer and fixed in 1% osmic acid buffered with phosphate. In other animals, the glutaraldehyde perfused tissue blocks were immersed for 1 hour in 3% glutaraldehyde/2.5% potassium iodate buffered as before. The paraganglia were then diced, separated into two vials and washed in the buffer. A portion of this tissue received osmic acid fixation.

Reconstruction of electron holograms recorded in a non-FEG, non-biprism TEM

1995 ◽  
Vol 53 ◽  
pp. 618-619
Author(s):  
Z.L. Wang
Keyword(s):  
Electron Microscope ◽  
Single Crystal ◽  
Experimental Technique ◽  
Transmission Electron Microscope ◽  
The Other ◽  
Electron Holography ◽  
Transmission Electron ◽  
Coherent Sources ◽  
Imaging Theory ◽  
Normal Specimen

An experimental technique for performing electron holography using a non-FEG, non-biprism transmission electron microscope (TEM) has been introduced by Ru et al. A double stacked specimens, one being a single crystal foil and the other the specimen, are loaded in the normal specimen position in TEM. The single crystal, which is placed onto the specimen, is responsible to produce two beams that are equivalent to two virtual coherent sources illuminating the specimen beneath, thus, permitting electron holography of the specimen. In this paper, the imaging theory of this technique is described. Procedures are introduced for digitally reconstructing the holograms.

Melatonin reduces high levels of lipid peroxidation induced by potassium iodate in porcine thyroid

2019 ◽  
pp. 1-7 ◽  
Author(s):  
Paulina Iwan ◽  
Jan Stepniak ◽  
Malgorzata Karbownik-Lewinska
Keyword(s):  
Lipid Peroxidation ◽  
Oxidative Damage ◽  
Membrane Lipids ◽  
Chemical Properties ◽  
Iodine Concentration ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Protective Effects ◽  
Potassium Iodate ◽  
Hormone Synthesis

Abstract. Iodine is essential for thyroid hormone synthesis. Under normal iodine supply, calculated physiological iodine concentration in the thyroid is approx. 9 mM. Either potassium iodide (KI) or potassium iodate (KIO3) are used in iodine prophylaxis. KI is confirmed as absolutely safe. KIO3 possesses chemical properties suggesting its potential toxicity. Melatonin (N-acetyl-5-methoxytryptamine) is an effective antioxidant and free radical scavenger. Study aims: to evaluate potential protective effects of melatonin against oxidative damage to membrane lipids (lipid peroxidation, LPO) induced by KI or KIO3 in porcine thyroid. Homogenates of twenty four (24) thyroids were incubated in presence of either KI or KIO3 without/with melatonin (5 mM). As melatonin was not effective against KI-induced LPO, in the next step only KIO3 was used. Homogenates were incubated in presence of KIO3 (200; 100; 50; 25; 20; 15; 10; 7.5; 5.0; 2.5; 1.25 mM) without/with melatonin or 17ß-estradiol. Five experiments were performed with different concentrations of melatonin (5.0; 2.5; 1.25; 1.0; 0.625 mM) and one with 17ß-estradiol (1.0 mM). Malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA) concentration (LPO index) was measured spectrophotometrically. KIO3 increased LPO with the strongest damaging effect (MDA + 4-HDA level: ≈1.28 nmol/mg protein, p < 0.05) revealed at concentrations of around 15 mM, thus corresponding to physiological iodine concentrations in the thyroid. Melatonin reduced LPO (MDA + 4-HDA levels: from ≈0.97 to ≈0,76 and from ≈0,64 to ≈0,49 nmol/mg protein, p < 0.05) induced by KIO3 at concentrations of 10 mM or 7.5 mM. Conclusion: Melatonin can reduce very strong oxidative damage to membrane lipids caused by KIO3 used in doses resulting in physiological iodine concentrations in the thyroid.

The Equivalent Conductance of Electrolytes in Mixed Solvents

1958 ◽  
Vol 17 (5_6) ◽  
pp. 300-314 ◽  
Author(s):  
Rayburn Whorton ◽  
Edward S. Amis
Keyword(s):  
Mixed Solvents ◽  
Equivalent Conductance

Front Matter

2019 ◽  
Vol 1 (1) ◽  
Author(s):  
Edy Saputra
Keyword(s):  
Experimental Technique ◽  
Legal Responsibility

Statements of fact and opinion in the articles in the Journal of Applied Materials and Technology are those of the respective authors and contributors and not of Journal of Applied Materials and Technology or the institution of Applied Materials and Technology Society and Faculty of Engineering, Universitas Riau. Neither Applied Materials and Technology Society and Faculty of Engineering, Universitas Riau nor Journal of Applied Materials and Technology make any representation, express or implied, in respect of the accuracy of the material in this journal and cannot accept any legal responsibility or liability for any errors or omissions that may be made by the reader should make her or his own evaluation as to the appropriateness or otherwise of any experimental technique described.

The Dinitrophenol and Potassium Iodate Influence on Hordeum Vulgare Seedlings Viability\

2018 ◽  
Vol 69 (8) ◽  
pp. 2160-2166
Author(s):  
Elena Todirascu Ciornea ◽  
Gabriela Dumitru ◽  
Ion Sandu
Keyword(s):  
Oxidative Stress ◽  
Hordeum Vulgare ◽  
Antioxidant Enzyme ◽  
Oxygen Radicals ◽  
Free Oxygen Radicals ◽  
Potassium Iodate ◽  
Free Oxygen ◽  
Oxidative Stress Enzymes ◽  
Stress Enzymes ◽  
Seeds Germination

The using of the pesticides of dinitrophenol type in agriculture has as consequence the major pollution of the environment, the plants taking these substances from the soil and once with these ones they reach in the human and animal organism where they product disequilibrium that are interpreted through the accumulation of free oxygen radicals with direct repercussions on the antioxidant enzyme�s synthesis intensification and on their activity�s increase. The apply of treatments on the barley seeds had significant effects regarding the seeds� germination, the young plants� growth, the oxidative stress enzymes� activity, but also regarding the content of photoassimilators and carotenoids pigments.

scholarly journals Theoretical Effect of Temperature on Threshold in the Hodgkin-Huxley Nerve Model

1966 ◽  
Vol 49 (5) ◽  
pp. 989-1005 ◽  
Author(s):  
Richard Fitzhugh
Keyword(s):  
Relaxation Time ◽  
Relaxation Times ◽  
Giant Axon ◽  
Temperature Curve ◽  
Effect Of Temperature ◽  
Threshold Temperature ◽  
Ionic Conductances ◽  
And Shifts ◽  
The Right ◽  
Increasing Temperature

In the squid giant axon, Sjodin and Mullins (1958), using 1 msec duration pulses, found a decrease of threshold with increasing temperature, while Guttman (1962), using 100 msec pulses, found an increase. Both results are qualitatively predicted by the Hodgkin-Huxley model. The threshold vs. temperature curve varies so much with the assumptions made regarding the temperature-dependence of the membrane ionic conductances that quantitative comparison between theory and experiment is not yet possible. For very short pulses, increasing temperature has two effects. (1) At lower temperatures the decrease of relaxation time of Na activation (m) relative to the electrical (RC) relaxation time favors excitation and decreases threshold. (2) For higher temperatures, effect (1) saturates, but the decreasing relaxation times of Na inactivation (h) and K activation (n) factor accommodation and increased threshold. The result is a U-shaped threshold temperature curve. R. Guttman has obtained such U-shaped curves for 50 µsec pulses. Assuming higher ionic conductances decreases the electrical relaxation time and shifts the curve to the right along the temperature axis. Making the conductances increase with temperature flattens the curve. Using very long pulses favors effect (2) over (1) and makes threshold increase monotonically with temperature.

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