Color continued theory

It has long been known that iodine dissolves in solvents possessing electron lone pairs and that the colors of these solutions are related to the solvent s basicity. Explaining this simple observation has required decades of work and has consistently required the application of the most sophisticated experimental tools available. The observation has also continually challenged theories of bonding, and even today taxes the capabilities of the fastest computers in efforts to provide accurate descriptions of its origin. 

The deposit made by the separation of dissolved carbonate of calcium from hard Avaters is thus interpreted by Pliny as an actual change of the Avater to the stone, a point of view entirely consistent Avith the theories of matter existent at the time. Thus Diodorus Siculus74 says of crystal (quartz), It is said that it is produced of the purest Avater congealed and hardened not by cold but by the power of the sun, so that it continues forever, and receives many shapes and colors, according as the spirits are exhaled. ... 

A solution of 91 g. (1 mol) of thiosemicarbazide4 in 350 ml. of 3 N HC1 (1 mol) is prepared. A clear solution is obtained at 30°. The solution is placed in a 1-1., threenecked flask equipped with a mechanical stirrer, thermometer, and dropping funnel and cooled in an ice-salt bath to 10°. A portion of the dissolved thiosemicarbazide precipitates at this stage. A solution of sodium nitrite, 69 g. (1 mol) in 150 ml. of water, is placed in the dropping funnel. The total volume of the solution is 180 ml. The sodium nitrite solution is added dropwise to the stirred mixture, while the temperature is maintained at 10°. When about 130 ml. of the solution has been added (45 minutes), the addition is stopped and the fine white crystalline precipitate filtered off. The filtrate, which is pale blue in color, is put back into the reaction flask and the addition of the sodium nitrite solution continued. The temperature of the reaction mixture should be maintained at 10 to 15° throughout the addition of the sodium nitrite. When about 40 ml. more of the sodium nitrite solution has been added (15 minutes), the reaction mixture tends to assume a very pale yellow color. Addition of the sodium nitrite is stopped at this stage and the rest of the precipitate filtered off. The addition of even a few drops of the sodium nitrite solution to the filtrate causes an intense yellow color. The filtrate is discarded at this stage. The combined precipitates of 5-amino-l,2,3,4-thiatriazole is washed three times with small amounts of ice-cold distilled water and dried under vacuum over sulfuric acid. The yield is 81.5 g. or 80% of theory, f... 

First, allow me to impart to you some of my present thoughts on the BET theory (3, 4) for whatever they are worth. [Reference (3) is a continuation and extension of the BET theory. Some authors refer to it as the BDDT theory others call both papers together the BET theory.] Probably there are very few among you who have never made a BET plot, and many of you have made quite a few. I suppose, it will surprise no one among you if I say that I made the first BET plot. I did not know at that time that it was a BET plot, because that name did not exist yet. I tried to give a name to the theory that the three of us had developed, and I called it the multimolecular adsorption theory, which was probably not a very good name, but it was the best I could think of. Fortunately, somewhat later Professor Harkins invented the colorful name BET theory, and that name has stuck. 

Though the Kubelka-Munk theory has proven to be adequate in many applications, it has significant deficiencies that prevent it from being a total solution for color matching. Kubelka-Munk theory continues to be popular because it provides simple analytical equations and reasonable predictions [2]. 

Fig. 1 Gas-liquid film theory for diffusion from the dispersed phase to the continuous phase (with maximum diffusion resistance in the continuous phase film). (View this art in color at www.dekker.com.)...

Another example to understand probability theory is as follows Nine clean, usable machine bolts and one defective machine bolt are aU placed in an opaque parts bag. The defective bolt is the same size, weight, and color as the nine clean bolts. Only the thread pattern on the bolt is defective, and this cannot be determined with the naked eye. What is the chance that the machinist will choose the defective bolt in a random selection exercise Since the position of each bolt in the bag and the selection process are completely uncontrolled factors, each of the 10 bolts has an equal chance of being chosen. The probability of selecting the defective bolt on the first draw is simply stated as a 1 in 10 chance, or. 1 in terms of probability. If this exercise were performed numerous times, the uncertainty of this probability level would become clear. For example, if the machinist were to continue to choose bolts 100 more times, and return the selected bolts to the parts bag between draws, the previously assigned probability level of. 1 would indicate that, out of 100 draws, the defective bolt would be pulled 10 times (100 x. 1). However, in actual practice, it is conceivably possible (although highly improbable)... 

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