...lifetime of the fluorescence (10-8 s) and thus competes effectively with fluorescence. Introduction: The aim of this experiment is to obtain the absorption and fluorescence spectrum in the organic dye molecule, Fluorescein. First, the spectrum of a xenon lamp was obtained using a monochromator combined with a photomultiplier tube detector. Then a fluorescence dye was inserted between the xenon lamp and the detector in order to obtain the absorption spectrum of the fluorescein dye. The equipment set up was then altered to investigate the fluorescence spectrum of the dye. The absorption spectrum and the fluorescence spectrum was plotted and compared. Theory: Fluorescence corresponds to the relaxation of the molecule from the singlet excited state to the singlet ground state with emission of light.1 In this experiment, the Fluorescence spectrum of a synthetic organic dye, Fluorescein was obtained and investigated. Fluorescein has the following molecular structure as figure [1] shows:...
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...Photometry 1) Principal of Flame Photometry: It is the conversion of molecules to their component atoms in gaseous state ; and it is carried out by introduction of the molecules solution in the flame in very fine droplet Atoms in gaseous state in the flame absorb thermal energy from the flame itself ,some of the atoms get excited & as they return back to the ground state they emit radiation having energy equal to that absorbed. The emission is proportional to the number of excited atoms, which is proportional to the total number of atoms in the flame i.e. the sample concentration When a metallic salt solution is aspirated into path of flame, following events takes place; 1) Vaporization: The solvent is vaporized leaving particles of solid salt. 2) Atomization : The salt is vaporized and converted into free neutral gaseous atoms or radicals 3) Excitation: Some of these atoms are excited by the thermal energy of the flame to higher energy levels.The various events are as follows, Sample Solution Fine Mist M+ X Solid Particles MX M+ X Ground State gaseous atoms Excited Gaseous Metal atoms Gaseous Atoms M(g)+ X(g) Gaseous Molecules MX The excited metal atoms are unstable at higher energy level, and quickly returns to lower energy state, while coming to lower energy they emit light of their own characteristic wavelength. The measurement emitted photons (light) forms the basis of flame photometry. The colour of the flame tells us which element is present (qualitative...
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...the concentration of Zinc in the sample. We have to be sure which sample we are used. Our laboratory report should describe the functions of the AAS and describe the procedures for preparing the instrument for use. The report should include a printout graph of the calibration curve that we have made. We also needed to indicate the data points for the calibration standards and our sample. INTRODUCTION Atomic absorption spectroscopy (AAS) determines the presence of metals in liquid samples. Metals include Fe, Cu, Al, Pb, Ca, Zn, Cd and many more. It also measures the concentrations of metals in the samples. Typical concentrations range in the low mg/L range. In their elemental form, metals will absorb ultraviolet light when they are excited by heat. Each metal has a characteristic wavelength that will be absorbed. The AAS instrument looks for a particular metal by focusing a beam of UV light at a specific wavelength through a flame and into a detector. The sample of interest is aspirated into the flame. If that metal is present in the sample, it will absorb some of the light, thus reducing its intensity. The instrument measures the change in intensity. A computer data system converts the change in intensity into an absorbance. As concentration goes up, absorbance goes up. The researcher can construct a calibration curve by running standards of various concentrations on the AAS and...
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...Maria Vasilenko 223901 Feasibility of using biosensors for heavy metal detection in complex matrices such as bio-slurries. Master of Science Thesis Examiners: Professor Matti Karp Professor Raghida Lepistö Examiner and topic approved in The Science and Bioengineering Department Council meeting on 7.11.2012 Abstract TAMPERE UNIVERSITY OF TECHNOLOGY Master‟s Degree Programme in Science and Bioengineering Vasilenko Maria: Feasibility of using biosensors for heavy metal detection in complex matrices such as bio-slurries. Seminar paper, 97 pages November 2012 Major: Biotechnology Examiners: Matti Karp, Raghida Lepisto Keywords: environmental pollution, heavy metals, biosensors, slurries The quality of bioslurries that are used in industrial production and agriculture need to be watched very closely to avoid spreading of contaminants on area and poisoning of humans and animals. Because heavy metals are very stable and toxic in many chemical compositions, their amount should be estimated very thoroughly. A new approach that involved biosensors was tested in this study. Because the slurries are complex non-unified matrices which composed of two phases – solid and liquid, the cell behavior can varies a lot from the one that explained in water and so the estimation of ion concentration can be not reliable. It was shown that the cell actually behave different in the slurries. Normally the dissolved compounds suppress the biosensor activity and, in the same time, the ions in the...
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...English 200 Section 049 Christopher Shipman “Too Excited To Sleep” Advertisements range from billboards to television commercials to jingles on the radio. Advertising companies have become adept at using images to grab the audience’s attention and implanting the subtlest of subliminal messages to keep the image of their products in the conscious and subconscious thoughts of the audience for extended periods of time. The Disney commercial, “Too Excited To Sleep” depicts two children that are supposed to be in bed but instead are whispering about their expectations of the trip to Disney World they are soon to take. The mother comes in and tells them to go to sleep, to which one of the children responds, “We’re too excited to sleep!” The commercial continues on to scenes of Disney World’s attractions and is concluded by the mother of the children asking the father if he’s asleep. At this point, the father responds, “No, I’m too excited to sleep.” By analyzing the use of image, humor, and fantasy in Disney’s commercial titled “Too Excited To Sleep” it is clear that the company successfully argues that Disney World is a desirable destination for adults, children, and families. In Disney’s commercial “I’m Too Excited To Sleep”, the advertisers use the imagery of fun and fantasy for all. The use of the family that is too excited to sleep gives the audience a mental image such as Santa visiting and other events that keep them awake from excitement. The scenes of exciting rides...
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...the door. Kevin realizes that Cromwell wants to go outside. Once Kevin ignored Cromwell, he went back to lay down. Kevin was too upset to play outside with Cromwell. "Sorry Cromwell, I'm not in the mood to play outside with you right now." Says Kevin, knowing that Cromwell can't understand him. Kevin thinks of an idea that might get Howie to pay for Cromwell's training classes. "I've got it, Cromwell, I have such a good idea, I know that Howie won't be able to deny this offer." Kevin says out loud. "I am going to buy him tickets to the soccer game that he really wants to go to." Kevin walks up to Howie all excited. "I have the best idea ever, how about if you pay for Cromwell's training classes, I will buy you tickets to the soccer game that I know you really want to go to."...
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...1. What is the difference between a. and a. To begin, the teacher will first write the word excited on the board and tell the students that “For my fictional narrative I want to include the point that, over break, I found $20 in the grass on a walk and I was very excited about it. First, what does fictional mean?” The teacher will call on a student to answer that fictional means fake. The teacher will ask what a narrative is, and a student will be called on to respond with the word story, or other synonym. 2. What is the difference between a'smart' and a'smart'? Next, the teacher will say “if in my story I just said I found $20 lying on the sidewalk and I was excited, is that very interesting to the reader” Students may shake their heads or respond to the prompt....
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...most exciting) 3. The weather is ___________________________ today than yesterday. (more beautiful, most beautiful) 4. Penny is ___________________________ than her sister. (more excited, most excited) 5. That's the ___________________________ spelling word we have been assigned this week. (more difficult, most difficult) 6. Basketball is a ___________________________ sport than fishing. (more physical, most physical) 7. Winter is the ___________________________ season of all. (more wonderful, most wonderful) 8. Bobby is a ___________________________ child than Jimmy. (more well-behaved, most well-behaved) Super Teacher Worksheets www.superteacherworksheets.com Name: ____________________________________________ Using More and Most with Adjectives Some adjectives compare by adding the words more and most. Use the word more with adjectives that compare two things. Use the word most with adjectives that compare three or more things. Choose the correct words in parenthesis to complete each sentence. Write the words on the line. 1. This is the most delicious chicken I've ever eaten. (more delicious, most delicious) 2. Football is the most exciting sport of all. (more exciting, most exciting) 3. The weather is more beautiful today than yesterday. (more beautiful, most beautiful) 4. Penny is more excited about the picnic than her...
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...could smell the funnel cake right next to the entrance. We walked past the ride earlier and it was long, so we decided to go get something to eat and go on other rides.I was nervous. “Are you excited to go on the ride.” said grandpa “Yeah, I am a little nervous tho.” I exclaimed I waited in line with my cousins, aunts, uncles, and my grandpa. While we stood in line my cousin and I were playing on the ledges in line and trying to find something to do to pass the time. It felt as slow as a hot summer's day....
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...of interest in the medical field. When I heard about the opportunity to volunteer at Rogue Regional medical center I was excited to take the opportunity. This opportunity made me very excited to be able to see the way the a Hospital and a NICU really works in a first person perspective. I’m so very grateful for this opportunity and I’m excited to learn all that I can. The first step to applying for this program is to fill out an application. They review your application you then get a list of things you must complete before you can volunteer. Some of the things you need to complete...
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...When 3-nitrophthalic acid, a dicarboxylic acid, is combined with hydrazine and heated, 3-nitrophthalhydrazine, a cyclic diamide is produced. The nitro group is then reduced with sodium dithionite, producing luminol. The nucleophile in this reaction is the nitrogen of the amine and the electrophile is the carbonyl carbon of 3-nitrophthalic acid. Since the carbonyl carbon is not a good electrophile, under normal conditions, the two reagents will not react. In this case, Fischer’s approach of running the reaction under acidic conditions would not work due to the basic nature of the amine. This would cause the amine to be protonated, making the ammonium ion, which is no longer a nucleophile. The problem can be solved by simply adding energy (heat) to the reaction. Because the high temperature used (heating to 230ºC), we need take to make sure everything, including the solvent, stays in solution. This can be done by running the reaction under pressure, but this poses a potential safety hazard. Instead, we can use a high boiling point solvent, such as triethylene glycol. Triethylene glycol has a boiling point of 285ºC and has similar solubility properties as water. At low temperatures, it is quite viscous, and doesn’t act as a good solvent. However, at high temperatures, it is ideal. A second problem involves obtaining such a high temperature. We use a hot plate, along with an aluminum heating block. Aluminum foil is placed around the heat block and conical vial to direct...
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...15th in my class, it shows how dedicated our class is. One characteristic that makes me stand out from my classmates is my hard work. Throughout my life I have been taught to do what seems impossible. Even though I am not the smartest in my class, I know I still am able to do as much as my other classmates. I have taken on a full schedule this year including calculus, physics, and DMACC classes. Taking these difficult classes made senior year very difficult, but all the hard work paid off. I am very proud to say I will be graduating with honors. This has been a large goal of mine. This has taught me how all your hard work will pay off in the end. Accomplishing this goal has made me set high standards for myself in college and I am excited to see where my hard work gets...
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...or in their ground state, when an certain amount of energy is absorbed, one or more electrons are brought out farther from the nucleus, into higher energy levels (or they get “excited”) making it unstable. Sent. 3 An unstable atom would quickly try to stabilize itself, “when the electron falls back to its original orbit, the energy released is a packet of light known as a photon”. (Arcand, Kimberly K., and Megan Watzke K. "Introducing Light." Introduction. Light: The Visible Spectrum and beyond. Black Dog & Leventhal, 2015. New York, New York.) Sent. 4 This process is called spontaneous emission of radiation, afterwards a process called stimulated emission will cause other electrons to release their photons form a coherent and collimated stream of light....
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...Section Two: Leadership Styles (Between 300 – 400 words) (E.R. 3.2) b. Compare and contrast two different leadership styles - Bring out the differences in the attributes and skills that are required for each leadership style - Elaborate on any four differences - Explain their significance for effective leadership in organizations Transactional Leadership These exchanges involve four dimensions: |[pic] |Contingent Rewards: Transactional leaders link the goal to rewards, clarify expectations, provide necessary resources, set mutually agreed | | |upon goals, and provide various kinds of rewards for successful performance. They set SMART (specific, measurable, attainable, realistic, | | |and timely) goals for their subordinates. | |[pic] |Active Management by Exception: Transactional leaders actively monitor the work of their subordinates, watch for deviations from rules and | | |standards and taking corrective action to prevent mistakes. | |[pic] |Passive Management by Exception: Transactional leaders intervene only when standards are not met or when the performance is not as per the | | |expectations. They may even use punishment as a response to unacceptable performance. | |[pic] |Laissez-faire: The...
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...I am excited, however for some things. I'm most nervous for the upperclassmen and assignments and I'm most excited for the freedom. Ninth grade, freshman year, fresh meat, no matter what you call it freshmen are the youngest. Upperclassman make me feel uneasy since, we have classes with them now. In the middle school you saw another grade one or two times a day. I am nervous I will look stupid in front of the upperclassmen. I might have a mental breakdown if I feel in front of them; especially if it was during the beginning of the school year. I am friends with some upperclassmen, but it is still scary to me. I am not looking forward to having classes with any of the older grades. I scheduled to take higher classes during freshman year. As I do believe I am very capable of learning the information, I am nervous I will get a lot of projects or assignments I won't be able to complete. I get overwhelmed quite often and it worries me that I will be overwhelmed twice as bad. Homework, projects, and essays all add up very quickly in my mind so, having of...
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