Spectral change of dye by UV-Vis measurement. Fig. 1 (b), shows the effect of different concentrations of aqueous TTAB on the absorption spectrum of 8ANS. In sub-micellar region, the addition of TTAB caused a bathochromic and hyperchromic shift at both the λmax. As far as the interaction is concerned, in sub-micellar region, (<3.5 mM) dye formed a sparingly soluble precipitate but which got solubilized as the TTAB concentration reached the CMC. This phenomenon was observed as the steep change in absorbance of the dye at both the corresponding λmax of the dye as shown in Fig. 1 (b). In aqueous solution of TTAB, as the dye molecules are added, initially the dye and surfactant are individually hydrated in the solution. Dye and TTAB sometimes meet each other in aqueous solution and the long range electrostatic and short-range hydrophobic forces caused the formation of dye surfactant complexes till the formation of the micelles. After micellization, no shift in the λmax was observed but the absorbance increased rapidly with each incremental addition of TTAB. CMCs were obtained from the combined spectra by monitoring the absorbance values near at 270 and 380 nm for different concentrations of TTAB. The inflection point of the absorbance versus [TTAB] plot was taken as the CMC of the corresponding TTAB solution [5, 40, 41]. About 40 spectra were accumulated for each CMC determination. CMC obtained by this method are given in the Table 1 and they are somewhat higher than that obtained from conductivity, surface tension measurements as well as from the literature values for the aqueous TTAB. It may be due to the interaction of the anionic dye with the cationic surfactant.
Initially the dye was added to the aqueous solution of ILs, once ...
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... both [Hmim][Br] and [Omim][Br] and the magnitude of decrease was higher than that in the presence of common electrolyte, NaBr. The somewhat higher value of CMC measured by spectral change of dye by UV-Vis method than conductance and surface tension methods may be due to the interaction of the anionic dye with the cationic surfactant. The increased hydrophobicity of the medium was confirmed by the shift of the λmax towards red shift. Surface tension measurement along with the DLS results indicated the formation of loosely packed structure at the higher concentration of ILs, thus confirming the co-surfactant like behaviour at higher concentration. It has been concluded that both the ILs behaved as electrolyte at lower concentration, forming the closely packed aggregates and co-surfactant at higher concentration leading to the formation of loosely packed aggregates.
Absorbance was defined as: log I_o/I where I_o is incident light and I is the transmitted light. Fluorescence emission spectrum is different from fluorescence excitation spectrum because it records different wavelengths of chemical s...
The analyzed yellow#5 wavelength was determined to 395nm because the actual wavelength 427nm was restricted in the Micro lab. The R2 value of the graph is 0.9827, and the level of data accuracy it indicated extremely weak data correlation. The first one dilution data points excluded from the standard curve because the point is not in the linear curve. The first concentration and absorbance value are the highest point in the graph that cannot connect as linear with another data point. After removing the first data point, the standard curve is clear and make
700 0.03 0.01 0 0 0.028. 720 0.01 0.01 0 0 0.02 0. Figure 2: The absorption spectrum shows how absorbent the photosynthetic pigments are at different wavelengths of light. Note: Green light is between 500 to 570 nm and red light is between 630 to 720 nm.
The color that was chose to be shined through the sample was purple. The spectrophotometer was set at a wavelength of 400nm to represent the purple color. It was zeroed using the blank meaning the spectrophotometer read zero as absorbance amount. The blank consisted of 5mL of water and 2.5 mL AVM and it was placed in cuvette. A solution with a known concentration of 2.0x10-4 M was used in the spectrometer. For this solution, 5 mL of the solution with 2.5 mL of AMV was placed in the cuvette. The cuvette was placed inside of spectrophotometer and the amount of absorbance was recorded. This procedure that involves a solution with a known concentration was repeated for the concentrations:1.0x10-4 M,5.0x10-5 M,2.0x10-5M, and1.0x10-5M.A unknown solution absorbance was measured by putting 5 mL of unknown solution with 2.5 mL AMV in a cuvette. The cuvette was placed in the spectrophotometer and the amount of absorbance was recorded. The procedure that deals with the unknown solution was repeated 2 more times with the same solution and the same amount of solution and AMV. The average of the three unknown solution was calculated and the concentration of the unknown solution was
Fig. 2(A) shows the phase diagrams of IPM, water, and surfactant mixtures at the ratios of 60:40, 65:35, and 70:30 (v/v), respectively. Fig. 2(B) shows the phase diagrams of ethyl oleate, water, and surfactant mixtures at ratios of 90:10, 95:5 and 100:0, respectively. Filled circles mean self-emulsifying points, and black areas represent the self-emulsifying regions. In other area, the compositions showed inverted emulsion, gel-like form, or phase-separation. In general, when the oil content in the oil and surfactant mixtures is ≤30%, the condition of the mixtures changed from water-in-oil emulsion to a clear gel-like form and then to microemulsion. Otherwise, the dispersions showed phase separation, this result was similar to the results previously studied by Guo et al. [16]. Our finding showed that IPM + surfactant mixture (65:35, v/v) and ethyl oleate + surfactant mixture (90:10, v/v) showed the most self-emulsifying regions (Fig. 2). Overall, in contrast to IPM + surfactant mixture (65:35, v/v), ethyl oleate + surfactant mixture (90:10, v/v) showed finer emulsion in larger self-emulsifying range. These results indicate that ethyl oleate and Tween 80:Carbitol (90:10, v/v) were identified as the optimal oil
... samples before the incubation of 108 seconds. Then the 100 µL of colour reagent was put to the sample, merged and incubated for further 10 minutes. The absorbance at 615nm and 700nm wavelengths was calculated on the samples in the Cobas analyser and the sample concentration was measure according to :
A low absorbency would have a low color change so would be clear or slightly clear by the end of the trails and a high absorbency would have a strong red color by the end of the experiment.
When shone through a coloured solution, the solution absorbs some wavelengths of the white light and transmits wavelengths that are not absorbed. When we look at the coloured solution, we see the transmitted light. The transmitted light is the only wavelength that is not absorbed. For example, if a solution absorbs all wavelengths except blue, the transmitted light will be blue. The transmitted light is complementary to the absorbed colour. Complementary colours are based on the three primary colours and the secondary colours that are made by mixing two of these primary colours. When two primary colours, for example, yellow and red, are mixed together, they create a secondary colour, in this example orange, that is complementary to the third primary colour, blue in this example. This is why if only orange light is absorbed from a solution, leaving primarily blue light to be transmitted, we see the solution as blue. Similarly, a solution may appear blue if it absorbs both red and yellow
Methanol, acetone, dichloromethane, toluene, and hexanes were tested for their miscibility with water. Methanol and acetone were found to be miscible with water, and dichloromethane, toluene, and hexanes were immiscible. Two layers—one organic and one aqueous—were observed each time an immiscible solvent was combined with water. Dichloromethane was observed as the bottom layer, and toluene and hexanes were observed as the top layers when added to test tubes of water. In Table 1 below, density, boiling point, and miscibility with water are shown for the organic solvents used in this experiment.1
Shakespeare develops a couple of themes through the story, one of them is: never be to trusty about your workers; remember that they are shooting for your place. In the book show how king Duncan gave all his trust on his thanes and servants (specially Macbeth) and he got betray by the ones he trust and admire the most. The following quotes will show my point. “Titles of nobility will shine like stars on all of who deserve them. (To Macbeth) and now, lets go to your castle at Inverness, where I will become even more obliged to you because of your hospitality.” (Kind Duncan, pg. 27 act 1 scene 4), this quote shows how king Duncan feel about Macbeth. “Now I´m decided, and I will exert every muscle in my body to commit this crime. Go now, and pretend to be a friendly hostess. Hide with a false pleasant face what you know in your false, evil heart.” (Macbeth, pg. 47, act 1 scene 7) But this one shows how Macbeth fells about not being a king.
... maximum decolorization of 97 and 77% was detected for Solar Blue A and Solar Flavine 5G at and temperature 50ºC and pH 4 respectively. They observed that by increasing incubation time and enzyme units, the % decolourization also enhanced. H2O2 dose of 0.7mM for Salar Flavin 5G and 0.8mM for Solar Blue A was enough for the dye degradation.
In the first part of the experiment, The mixture was combined with saturated sodium chloride, and the aqueous layer, containing alcohol, some acid, and water, was discarded. The organic layer was then dried with granular anhydrous sodium sulfate; this drying agent is used to absorb any water in a solution and should thus, result in a colorless solution. The final product was collected; it was mostly clear, though it has a pale yellow tint. Data Table 2 shows the results and calculations that were gathered after the completion of this experiment. No errors had occurred during the course of the experiment, which is testified by the fairly, high yield of Data Table 3 indicates the observations from these tests.
All things, living or nonliving, consist of atoms and molecules. These particles are constantly in motion, and this continuous motion allows for the disbursement of molecules, or diffusion. The overall net movement of these molecules will go from areas of higher concentration, to areas of lower concentration. Therefore, following a concentration gradient (Martini). The rate of diffusion of these molecules, in accordance with Fick’s law of diffusion, is directly proportional to the concentration gradient present. However, the concentration gradient is not static and will change over time and with distance, therefore changing the rate of diffusion. It is hypothesized that the two solutions being tested, Methylene Blue and Potassium Permanganate, will begin their initial diffusion in the agar gel at a quick rate, and then progressively regress over the allotted time of 1 hour. Another factors other that will have an effect on rate of diffusion is molecular size. There is a substantial difference in molecular weight between Methylene Blue (320 g/mol) and Potassium Permanganate (158 g/mol). The combined molecules present in Potassium Permanganate are lighter than those in Methylene Blue, and therefore should allow it to diffuse more rapidly.
Four solutions were tested an out of the four only one had a color change, meaning that it had alcohol present. This solution was methanol and of course it would produce a color change because methanol is an alcohol. One solution that should have changed color was solution 4, the base-hydrolyzed aspartame, but it did not produce a color change when aqueous ceric ammonium nitrate reagent. Water and fresh aqueous aspartame are not going to produce a color change because there is no alcohol group in there structure.
...e industries, textile industries are considered as one of the major sources of wastewater in ASEAN countries. Dyes are also used in industries such as rubber, paper & pulp, dye & dye intermediate industries, pharmaceutical, tannery, food technology, hair coloring, plastic, cosmetic etc. There are more than 10,000 commercially available dyes with over 7x105 tones of dyestuff being produced annually across the world2.. The textile industry consumes more than 107 kg of dye per year of which 90% ending up on fabrics3. Of this total usage 10- 15% of the dye is lost during the dyeing process and released with the effluent. Colour is contributed by phenolic compounds such as tannins, lignins (2-3%) and organic colourants (3-4%) and with a maximum contributions from dye and dye intermediates which could be sulphur/ mordant/ reactive/ cationic/ dispersed/acid/azo vat dye4.