MiscellaneousLPT: If you are having a lot of copper pipework replaced, request that you keep it and sell it to your local scrap dealer. LifeProTips)submitted by Usually, plumbers/builders will take this themselves and make money from your old pipework. Copper is valuable and could help contribute towards your renovations.We're sorry, we encountered an error while processing your request.We apologize for any inconvenience. If the problem persists, please contact us. (Please include the URL of the page you were trying to access.) Cloud Computing & Virtualization Graphics & Web Design Home & Office Computing Mobile Application Development & Programming NetworkingOpen SourceOperating Systems, ServerProcess ImprovementProgrammingSecurity Software Development & Management Web DevelopmentWeb ServicesStoreBookseBooksPractice TestsSoftwareVideoWeb EditionsAuthorsSafariImprintsAddison-Wesley ProfessionalCisco PressIBM PressPearson IT CertificationPrentice Hall ProfessionalQue PublishingSams PublishingVMware PressExploreAboutAffiliatesArticlesBlogsCommunityDeals and PromotionsNewslettersPressUser Groups

All of our prices are Real Time. Trust is an important part of business today.  In these tough economic times, you need someone on your side.  Owl Metals Inc pays the most for all of your Steel in Baltimore MD.  This way you can focus on growing your business and let us focus on growing your wallet.  We are constantly coming up with new and inventive ways to process scrap metals so that we can pay you More For Your Metals. Fast and Friendly Drive-Thru Big and Small, We Do It All Owl Metals Inc. invites you to call during business hours at 410-282-0068 Monday-Friday:  8:00 AM to 4:30 PM Saturday:  8:00 AM to 12:00 noon Steel customers must be here 30 mins prior to closing. All other customers must be in line 15 mins prior to closing. We pay the highest prices in Baltimore MD for your Gold and Silver, Platinum, Cell Phone and Tablet, Copper, Aluminum, Brass, Lead, and Steel. Our customers love us because we purchase a wide range of specialty metals based on their content alone.

A fast and friendly drive-thru service where our employees unload your vehicle offers you a knowledgeable and courteous experience.air conditioner window unit filter © Copyright 2013 Owl Metals Inc.OWL METALS INC | how to drain water from ac unitWHO WE ARE | ac unit running not coolingWHAT WE BUY | GOLD AND SILVER | STOP METAL THEFT |  Many compounds absorb ultraviolet (UV) or visible (Vis.) light. The diagram below shows a beam of monochromatic radiation of radiant power P0, directed at a sample solution. Absorption takes place and the beam of radiation leaving the sample has radiant The amount of radiation absorbed may be measured in a number Transmittance, T = P / P0 A = 2 - log10

The last equation, A = 2 - log10 %T , is worth remembering because it allows you to easily calculate absorbance from percentage transmittance data. The relationship between absorbance and transmittance is illustrated in the following diagram: So, if all the light passes through a solution without any absorption, then absorbance is zero, and percent transmittance is 100%. If all the light is absorbed, then percent transmittance is zero, and absorption Now let us look at the Beer-Lambert law and explore it's significance. This is important because people who use the law often don't understand it - even though the equation representing the law is so straightforward: Where A is absorbance (no units, since A = log10 P0 / P ) e is the molar absorbtivity with units of L mol-1 b is the path length of the sample - that is, the path length of the cuvette in which the sample is contained. We will express this c is the concentration of the compound in solution, expressed in mol

The reason why we prefer to express the law with this equation is because absorbance is directly proportional to the other parameters, as long as the law is obeyed. We are not going to deal with deviations from the law. Let's have a look at a few questions... Question : Why do we prefer to express the Beer-Lambert law using absorbance as a measure of the absorption rather than %T ? Answer : To begin, let's think about the equations... %T = 100 P/P0 = e Now, suppose we have a solution of copper sulphate (which appears blue because it has an absorption maximum at 600 nm). We look at the way in which the intensity of the light (radiant power) changes as it passes through the solution in a 1 cm cuvette. We will look at the reduction every 0.2 cm as shown in the diagram below. The Law says that the fraction of the light absorbed by each layer of solution is the same. For our illustration, we will suppose that this fraction is 0.5 for each 0.2 cm "layer" and calculate the

tells us that absorbance depends on the total quantity of the absorbing compound in the light path through the cuvette. If we plot absorbance against concentration, we get a straight line passing through the origin (0,0). Note that the Law is not obeyed at high concentrations. from the Law is not dealt with here. The linear relationship between concentration and absorbance is both simple and straightforward, which is why we prefer to express the Beer-Lambert law using absorbance as a measure of the absorption rather than Question : What is the significance of the molar absorbtivity, Answer : To begin we will rearrange the equation A = In words, this relationship can be stated as "e is a measure of the amount of light absorbed per unit concentration". Molar absorbtivity is a constant for a particular substance, so if the concentration of the solution is halved so is the absorbance, which is exactly what you would expect.

Let us take a compound with a very high value of molar absorbtivity, say 100,000 L mol-1 cm-1, which is in a solution in a 1 cm pathlength cuvette and gives an absorbance / 1 ´ c Therefore, c = 1 / 100,000 = 1 ´ Now let us take a compound with a very low value of e, say 20 L mol-1 cm-1 which is in solution in a 1 cm pathlength cuvette and gives an Therefore, c = 1 / 20 = 0.05 mol L-1 The answer is now obvious - a compound with a high molar absorbtivity is very effective at absorbing light (of the appropriate wavelength), and hence low concentrations of a compound with a high molar absorbtivity can Question : What is the molar absorbtivity of Cu2+ ions in an aqueous solution of CuSO4It is either 20 or 100,000 L mol-1 cm-1 Answer : I am guessing that you think the higher value is correct, because copper sulphate solutions you have seen are usually a beautiful bright blue colour. However, the actual molar absorbtivity value