Topic :: Extinction
How much is the molar extinction coefficient of methylene blue at wavelenght 664 nm? Are molar extinction coefficient depend on concentration of solution?
3 24648Calculate the molar extinction coefficient of a solution containing 5 *10-4 g litre-1 of a biomolecule, molecular weight 275 g mol-1, and absorbance 0.75 in a 1.2 cm cuvette.
2692Question 90 - In the calculation of the growth of bacteria, absorbance, A in spectrophotometry is used. According to Beer-Lambert Law, A = e x l x c where A is the absorbance of the solution (no unit), l is the distance of light travels through the solution (in cm), e is the molar absorptivity or the molar extinction coefficient [ in L / (mol.cm) ]. For a particular solute and fixed path length : As / Ao = Cs / Co where Ao is the observed signal for a known concentration Co, and As is the observed signal for a sample concentration Cs. (a) For a cell concentration of 560 cells / mL, a spectrophotometre gives an absorbance reading of 1.0. A mixture of concentration 3600000 cells / mL can be diluted in several operations, with each operation having a dilution of 1:20. How many dilutions should be made so that the concentration of this mixture can be calculated within a range of A = 0.0 to 1.0. (b) In another experiment, a sample tube of 1 cm in width is used. Let A = 0.06 and e = 0.0012 ml / (cell.cm). Find the cell concentration of the sample.
1 1587Question 91 - In the application of Theory of Spectrometry in spectrophotometer, let n = N x C x V, V = A x t, e = a x N where n = number of molecules, N = Avogadro's number, V = volume of cuvette, A = area of cuvette, t = thickness of cuvette, C = concentration of fluid in the cuvette, e = extinction coefficient, a = effective area of molecule. (a) By using calculus in dI = -I x a x N x C x dt, prove that ln (I / Io) = -a x N x C x t, where dI is the small difference in I and dt is the small difference in t. I = intensity of light. Io = initial intensity of light. (b) Show by calculations that ln (Io / I) = e x C x t based on the answer in the previous question (a). (c) Find the equation of log (Io / I) as a function of e, C and t based on the answer in the previous question (b).
1 1645MICROBIOLOGICAL ENGINEERING - QUESTION 28.3 : In the calculation of the growth of bacteria, absorbance, A in spectrophotometry is used. According to Beer-Lambert Law, A = e x l x c where A is the absorbance of the solution (no unit), l is the distance of light travels through the solution (in cm), e is the molar absorptivity or the molar extinction coefficient [ in L / (mol.cm) ]. For a particular solute and fixed path length : As / Ao = Cs / Co where Ao is the observed signal for a known concentration Co, and As is the observed signal for a sample concentration Cs. (a) For a cell concentration of 560 cells / mL, a spectrophotometre gives an absorbance reading of 1.0. A mixture of concentration 3600000 cells / mL can be diluted in several operations, with each operation having a dilution of 1:20. How many dilutions should be made so that the concentration of this mixture can be calculated within a range of A = 0.0 to 1.0. (b) In another experiment, a sample tube of 1 cm in width is used. Let A = 0.06 and e = 0.0012 ml / (cell.cm). Find the cell concentration of the sample.
1 1732BIOCHEMICAL ENGINEERING INSTRUMENTATION - EXAMPLE 29.1 : In the application of Theory of Spectrometry in spectrophotometer, let n = N x C x V, V = A x t, e = a x N where n = number of molecules, N = Avogadro's number, V = volume of cuvette, A = area of cuvette, t = thickness of cuvette, C = concentration of fluid in the cuvette, e = extinction coefficient, a = effective area of molecule. (a) By using calculus in dI = -I x a x N x C x dt, prove that ln (I / Io) = -a x N x C x t, where dI is the small difference in I and dt is the small difference in t. I = intensity of light. Io = initial intensity of light. (b) Show by calculations that ln (Io / I) = e x C x t based on the answer in the previous question (a). (c) Find the equation of log (Io / I) as a function of e, C and t based on the answer in the previous question (b).
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Calculate the molar extinction coefficient of a solution containing 5 *10-4 g litre-1 of a biomolecule, molecular weight 275 g mol-1, and absorbance 0.75 in a 1.2 cm cuvette.
what is the extinction coefficient for Indomethacin or at 319nm wave length.
You are the project manager for a top-secret software project for an agency of the United States Government. Your mission, should you choose to accept it, is to complete the project using internal resources. The reason is because getting top secret clearances for contractors takes quite a bit of time and waiting for clearances would jeopardize the implementation date. Your programmers are 80 percent of the way through the programming and testing work when your agency appoints a new executive director. Slowly but surely your programmers are taken off this project and reassigned to the executive director's hot new project. Which of the following type of project ending is this? A. Starvation B. Extinction C. Addition D. Integration
All of the following are types of project closures or endings except: A. Addition B. Integration C. Verification D. Extinction
You are a project manager for Cinema Snicker Productions. Your company specializes in producing comedy films for the big screen. Your latest project has just been completed and accepted. You've been given your next project, which starts right away. Which of the following is true? A. This project ended due to extinction because it was completed and accepted. B. This project ended due to integration because it was completed and accepted and the project manager moved on to a new project. C. This project ended due to addition because it was completed and accepted and archived into the company's catalog of available films. D. This project ended due to integration because it was completed and accepted.
You are a project manager for Snow Fun, a chain of retail shops specializing in winter sports gear and clothing. You’ve been working on contract with Snow Fun and are ready to move on to your next assignment. The customer has signed off on the project, formal acceptance notices have been distributed, and project closure procedures have been performed. What type of project ending is this? A. Extinction B. Starvation C. Integration D. Addition
What is the name of the deer which is on th everge of extinction?
What is the name of the deer which is on the averge of extinction?
