Chemical shift

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  • Nucleobases Lab Report

    organic molecules based on the atomic nuclei interactions with their environment. Recent advances have made use of the technology in protein, nucleic acid, and complex natural products structure identification. [1, 2, 3] Its origins lie in the works of Felix Bloch and Edward Purcell, who used the discoveries of Isidor Rabi’s extension on Stern-Gerlach experiment, and were awarded the Nobel Prize in 1952 for their use of NMR on solids and liquids. Packard notably observes this phenomena of nuclear resonance when a magnetic field was applied to an organic molecule by the absorption of RF (radiofrequency) in a magnetic field.[4] This knowledge was expanded to identify structural components of organic molecules based on their reported magnetic shifts caused by the induced change in their spin states. The technique became useful in many areas of chemistry for its versatility and reproducibility. The peaks for the NMR spectra are determined by energetic changes of the spin resonance.[5] Some elements’ spin states exist as fractional spins in the presence of an external magnetic field; particularly for hydrogen, the spin value can be ±1/2. [5] The energy difference between these two states can be calculated knowing the strength of the applied external magnetic field, the magnetic momentum of the element’s nuclei, and the spin.[5] This relationship is represented by this equation: ∆E=uB/I , where I is the spin and u is the magnetic momentum. ∆E equals hν when the frequency of the…

    Words: 1614 - Pages: 7
  • - 6-Diphenyl-2-Cyclohexenone Lab Report

    found, but only six represented 6-ethoxycarbonyl-3,5-diphenyl-2-cyclohexenone. Impurities found at 2.20 ppm, 1.69 ppm and 1.249 ppm, were caused by acetone and a small amount of residue in the NMR tube. These impurities were only present in 1H NMR, so only the sample contained a small amount of impurities. The peaks found at 7.47 ppm, 6.58 ppm, 4.05 ppm, 3.80 ppm, and 1.04 ppm, are the peaks that represent the 6-ethoxycarbonyl-3,5-diphenyl-2-cyclohexenone. The multiplet at 7.47 ppm represents…

    Words: 928 - Pages: 4
  • Pyrimid Chromatography Lab Report

    new opportunities for the rational design of medicinal agents. Encouragingly, most of the synthesized derivatives possess potent PDE 5 inhibitory activity compared to sildenafil as a reference drug. Experimental section General Melting points were determined on a Boetius melting point apparatus and are uncorrected. Elemental analyses were performed on Carlo Erba CHN-S Elemental analyses 1108. Institute of Chemistry Dresden, Germany. The NMR spectra were obtained using a Brucker AC 300 (300.13…

    Words: 1222 - Pages: 5
  • Body Synthesis Protocol Analysis

    optimisation because they "are groups or molecules which have chemical and physical similarities producing broadly similar biological properties" (Brown, 2012) to the original functional group. Bioisosteric substitutions consider important attributes including size (molecular weight), shape (bond angles and hybridization states), electronic distribution (polarizability, inductive effects, charge and dipoles), lipid and water solubility, pKa, chemical reactivity, and hydrogen bonding capacity…

    Words: 1392 - Pages: 6
  • Ethyl Cinnamate Synthesis

    Experiment 5 Synthesis and NMR Spectroscopy of ethyl cinnamate Introduction: Wittig reactions involve the stereoselective synthesis of olefins from phosphonium ylides and aldehydes or ketones, where the carbonyl bond is converted to an alkene double bond.1 The variety of suitable reagents and the relatively mild experimental conditions facilitate their industrial applications, such as the synthesis of epoxides, esters, carotenoids and vitamin A.2,3 Specifically, the ester ethyl cinnamate is used…

    Words: 921 - Pages: 4
  • Cell Count Procedure

    areas. This is a lot of tasks to complete in what one considers to be a typical work day, so many employees are easily able to obtain large amounts of overtime if they please. A large part of the job is time management, some tests will be more important than others, meaning they will be need to done before other tests and the results sent out very quickly. While other tests must be done in a specific sequential order while even more requests come in. Keeping up with the tests are very important,…

    Words: 1168 - Pages: 5
  • Essay On Unfair Dress Codes

    firing a woman for being pregnant. I was often on the receiving end of some unwanted advice from my boss on various subjects ranging from my marriage to my looks, while my male coworkers were never treated with such criticism, only respect. My boss was the most unprofessional boss I have ever had. I was told on the day I was hired that I needed to wear dress clothes during my shift, so the next day I went out and bought some nice blouses and a pair of dress pants, as my boss had suggested, not…

    Words: 821 - Pages: 4
  • Nursing Shortage Analysis

    Nurses no longer sleep in wards near their patients. The 24-hour clock has been split into shift work. Initially the split was three 8-hour shifts, but in the 1970s to aid in the alleviation of the nursing shortage 24-hour staffing was changed to two 12-hour shifts (Rollins, 2015). Most nurses found the 12-hour shifts appealing. The 12-hour shifts led to less work hours and less work days, allowing nurses to better balance their job and family life. However, this change adversely affected the…

    Words: 1800 - Pages: 8
  • Shift Work And Job Satisfaction Case Study

    burden of shift work and job satisfaction among nurses in Winter Park Memorial Hospital. The study will examine the association of predictors between working long shifts and burnout to age, annual salary received, earned years of education and time spent in shift work schedules. Furthermore, the study will help identify potential strategies for improving the quality of life of shift-working nurses. Literature Review In our society today, it is a recognized fact to work beyond the outside…

    Words: 1486 - Pages: 6
  • Personal Narrative-Catholic Versus Public School

    “This is by far our biggest game of the year. You need to go out there and give one hundred percent every shift. Play with the intensity you’ve been playing with all year. If you do that, if you leave it all on the ice, you can walk the halls tomorrow at school and feel proud of yourselves. Wear that jersey with pride tonight boys because this is your time.” My coach’s words were ringing through my head as I was on the bench waiting for my first shift. I couldn’t stop moving my legs when I was…

    Words: 1033 - Pages: 4
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