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there is such a commercial product. immersion glass for the diagnosis of diamond defects, commercial name s255_1. its predominance is 2.41, the softening temperature is 130 degrees Celsius. we use such a drug.


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I have read the article but it was never mentioned what part of the flame does the transducer or sensor was placed on. It was never mentioned because no sensor or transducer is actually placed on or in the flame. What spectroscopist do is that they focus the light (coming from the flame) into a device called the monochromator. The job of the monochromator ...


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The three signals are very close in CS, and have a strong coupling. If you have heard about $AB$ spin systems, where the CS difference is similar to the coupling constant, which make the outer two lines of the two doubletts become weaker, and the innner two stronger and move closer to one another: This is an $AB_2C_2$ system. The inner lines coalesce ...


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Experimental design also comes into the fray. If you have an apparatus that is not quantitatively accurate, you can apply it to your experimental ssmple and to a control for ccx which you have a reference value of what you are trying to measure. You then calibrate your results to the known reference. I've used this approach at work, to compare acid ...


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To add to @Poutnik's and @M.Farooq's answers: Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means? No, because what you can and should do in terms of maths/statistics depends very much on your application and data generation/measurement processes. Using only mathematical means is ...


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Generally, improvement of measurement process has much better positive impact on results, than sophisticated mathematical processing of low quality data. But, sometimes we are forced to data what we have. There are 3 quantities: resolution = the smallest difference of directly measured value, distinguishable by the tool, precision = Level of uncertainty ...


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Your non-trivial question has a yes and a no. It is not possible to increase the accuracy of a dataset just by mathematical means. If you knew the systematic error in your data then you can do the arithmetic to correct the error. There is no a priori way to ascertain if your measurement tool lacks accuracy until and unless we have a reference for comparison. ...


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According to Skoog, Analytical Chemistry: Using classical mechanics, assuming a diatomic molecule, the frequency of vibration $\nu$ may be described by $$\nu = \frac{1}{2\pi} \sqrt{\frac{k}{\mu}} $$ where $k$ represents the force constant of this bond, and $\mu$ the reduced mass of the particles bond together, defined as $$\mu = \frac{m_1 \cdot m_2} {...


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A property of the harmonic oscillator is that the oscillation frequency, $\omega$, is dependent not only on $k$ (the spring constant) but also on the mass $m$ of the object: $$\omega = \sqrt{\frac{k}{m}}$$ We can crudely model a chemical bond as a two-body harmonic oscillator, which largely obeys the same rule, except that the mass must be replaced with ...


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Try searching Google Scholar and write HPLC separation and the names of your compounds. You will find plenty of publications and of course column names. If your compounds are new, you should test the solubility in MeOH, ACN, and 50:50 MeOH/H2O and 50:50 ACN/H2O. Do they dissolve in such solvents systems? If they do, you would use C-18 RPLC columns. There are ...


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Stanislav, that is a Nobel Prize winning question. In short, nobody knows nitty-gritty details of how the electrospray ionization imparts a charge to the analyte. When Fenn (reinvented) the electrospray phenomenon and used for ionizing large biomolecules he was shocked and gave an analogy that it is like making the elephants fly. He got a Nobel Prize as well ...


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