This study spawned numerous articles in scientific and the mass media regarding the potential contribution to blindness from blue light emitted by personal devices including smart phones, tablets, computers etc. From Safety and Health Blue light from electronic devices, sun may damage vision Exposure to blue light from the sun and electronic devices may destroy cells in the retina and accelerate the onset of blindness Researchers discovered that emissions of blue light cause retinal molecules, which sense light and send signals to the brain, to produce toxic chemical molecules in photoreceptor cells that help the eye to see.
The results of the experiments determine the health of a particular body of water and can also predict other oxygen-related activities in the water. The Winkler titration method remains in use and also serves as a basis for adaptations made to methods for testing dissolved oxygen in both fresh and saltwater samples.
History Lajos Winkler developed the Winkler method as part of his doctoral dissertation for the Budapest University of Science in Although modern usage of the method frequently applies to work conducted by environmentalists and ecologists, Winkler came up with the process as a way of measuring high-pressure boilers.
Determining the amount of oxygen dissolved in a high-pressure boiler helped him evaluate the corrosion resistance of the boilers. Modern Uses Environmentalists and ecologists primarily use the Winkler method for three determinations.
First, the method provides insight with regard to the health and cleanliness of a body of water. Second, it also gives an indication of how much and what type of biomass it can support. Finally, dissolved oxygen levels serve as an indicator of the amount of decomposition occurring in the water, which evidences a healthy life cycle of nearby plants.
Added to the water are two reagents: These reagents are added individually under the surface of the water and slowly to prevent exposure to oxygen through bubbles.
The solution is inverted to mix the reagents together with the water, and then 2 milliliters of concentrated sulfuric acid get added from above the water surface. This completed solution then becomes titrated with drops of sodium thiosulfate until it produces a pale straw color. After completion, scientists add 2 milliliters starch solution, which turns the water solution blue.
Individual drops of sodium thiosulfate are titrated into the solution until the solution becomes clear, which marks the end of the method process. Results Each milliliter of sodium thiosulfate equates to one milligram per liter of dissolved oxygen.
The total milliliters of sodium thiosulfate used to turn the solution pale straw, and then clear, equates to the total amount of dissolved oxygen in the water sample. Since gas becomes more soluble in cold water than warm water, expected results should indicate higher levels of dissolved oxygen in colder water than in hotter water samples.
Alternative Instruments and Adaptations Sincemodern-day tools and instruments that produce instant measurements of dissolved oxygen largely reduce the need for the Winkler titration method. However, many scientists who use these instruments periodically resort to the Winkler titration method to test the accuracy of the results and make sure their instruments are recording data correctly.
Additionally, many adaptations of the Winkler method have been developed since the original method was introduced. Some of these adaptations use iodine and citric acid in place of original reagents.Liu and associates () studied the effects of BTX-A on the treatment of hypertrophic scars (HS) and the dose response of BTX-A.
Hypertrophic scars were harvested from the ears of 18 young adult New Zealand big-eared rabbits and treated with BTX-A or triamcinolone acetonide (TAC) in-vivo experiment. Conclusion For Winkler Method Experiment Modified Winkler method for dissolved oxygen determination Abstract In this study the group has determined the presence of oxygen in sample through a modified winkler method.
"Conclusion For Winkler Method Experiment" Essays and Research Papers Conclusion For Winkler Method Experiment Modified Winkler method for dissolved oxygen determination Abstract In this study the group has determined the presence of oxygen in sample through a modified winkler method.
Oct 02, · From our experiment, we can conclude that as the temperature of a water sample increases, the amount of dissolved oxygen decreases, thus the percentage of saturation increases. From this, we can determine that warmer water has more oxygen, and thus, is a more productive environment. The most common B12 used in supplements is called Cyanocobalamine (Cobalamine). The body must convert Cobalamine to Methylcobalamine in order to get adequate levels of . "Conclusion For Winkler Method Experiment" Essays and Research Papers Conclusion For Winkler Method Experiment Modified Winkler method for dissolved oxygen determination Abstract In this study the group has determined the presence of oxygen in sample through a modified winkler method.
The most common B12 used in supplements is called Cyanocobalamine (Cobalamine). The body must convert Cobalamine to Methylcobalamine in order to get adequate levels of .
(Information Page for Therapists) Preface. For the purposes of this discussion, blue light is defined as light within the wavelength range of nm, because over 88% of the risk of photo-oxidative damage to the retina from fluorescent lamps (cool white or "broad spectrum") is due to light wavelengths in the range of nm.
Methods. Measurement of Dissolved Oxygen. The sample bottle was filled completely so that there were no air bubbles in the bottle. The sample bottle was left in the refrigerator until it reached 5° C.