factors affecting on vibrational frequencies in IR.

factors affecting on vibrational frequencies in IR.:                                                                        1.coupled vibrations,2.fermi resonance,3.electronic effects and 4.hydrogen bonding.                                                 1.coupled vibrations:an isolated C-H bond has only one stretching vibrational frequency where as methylene group shows two stretching vibrations symmetrical and asymmetrical.                                  assymetric vibrations occur at higher frequencies than symmetric vibrations. these are known as coupled vibrations because these vibrations occur at different frequeencies than that required for an isolated C-H stretching.                                                                                                                         a strong vibrational coupling is present in carboxylic  acid anhydrides in which symmetrical and asymmetrical stretching vibrations appear in the range of 1720-1825/cm.the interaction is effective because of partial double bond due to resonance which keeps system planar for effective coupling.      assymetrical stretching band in acyclic anhydride is more intense while symmetrical stretching band in cyclic anhydride is more intense.                                                                                 Fermi resonance:a fermi resonance is shifting of energies and intensities of absorption bands in the infrared or raman spectrum.the phenomenon is explained by the italian physicist enrico fermi.                                                                                                                                      conditions for fermi resonance:                                                        1.the two vibrations must have same energies.and 2.the transitions must have same energies.           fermi resonance most often occurs between normal and overtone modes.                                                In this molecule transfer its energy from fundamental vibrational level to overtone or combination level.                                                                                                                                                            

Fourier transformer infrared spectroscopy:It is used to obtain infrared spectrum of absorption or emission of solid,liqud or gas.FTIR collects high spectral resolution data over a wide spectral range.it is advantageous over dispersive spectrophotometer.                                                                                

combination bands,overtones and fermi resonance

These are used to help and explain and assign peaks in the vibrational spectra that do not correspond to fundamental vibrations.combination bands and overtones have low intensities than fundamental and fermi resonance causes shift in the intensities of peaks with similar energies and identical symmetries.                                                                                                                                                Introduction:fundamental vibrational frequencies of a molecule corresponds to a transition from v=0 to v=1.for a non linear molecule there will be 3n-6  number vibrations while for liner molecule there will be 3n-5 no vibrations because there is one less  rotational degrees of freedom.        following figure shows a diagram for vibrating diatomic molecule.the levels denoted by vibrational quantum numbers v represent the potential energy for the harmonic oscillator.the transition 0 to 1 is fundamental,transitions from 0 to n are  overtones and from 1 to n are hot transitions                          

potential energy diagram for a vibrating diatomic molecule

Fermi resonance:a fermi resonance is shifting of energies and intensities of absorption bands in the infrared or raman spectrum.the phenomenon is explained by the italian physicist enrico fermi.                                                                                                                                                        conditions for fermi resonance:                                                        1.the two vibrations must have same energies.and 2.the transitions must have same energies.           fermi resonance most often occurs between normal and overtone modes.                                                In this molecule transfer its energy from fundamental vibrational level to overtone or combination level.

opiod analgesics

opiods are substances that act on opiod receptors and produce morphine like effects.these are generally used to relieve pain.the drugs are derived from opium alkaloid.these drugs mainly includes synthetic and semisynthetic drugs such as hydrocodon,oxycodon and fentanyl.antagonist drugs such as naloxone. besides used as pain reliever these are used for treating cough also                                       medical uses: pain,acute pain,chronic non cancer pain etc.                                                                      other:cough,diarrhoea and shortness of breadth                                                                                 adverse effects:nausea and vomitting,drowsiness,itching,constipation,respiratory depression,opiod induced hyperalgesia.                                                                                                                                    

                                   

DOP/PAO Test

What is a DOP/PAO Test ?

DOP/PAO testing is a very quick process that tests the integrity of the HEPA (High Efficiency Particulate Air) filter using DOP or PAO solutions in their operational conditions.

These solutions generate a gas type smoke and then generate gas particles that will be greater than .03 microns. The test will certify the HEPA filter is fully functioning and there is no leakage or damage.

Meaning of DOP?

DOP (Dispersed Oil Particulate) is a dispersed aerosol used to test the integrity of HEPA filters.

Meaning of PAO?

PAO (Poly Alpha Olefin) is a non-carcinogen liquid which is a most common replacement for DOP.                                                                                                                                              When to do DOP test

Any equipment that has a HEPA filter should be tested every time the equipment is moved or going to be used on a new project (every four weeks if on same project). For the best results testing should be done on-site to ensure that the units have not been damaged due to transportation or daily activities at the work site.

 this is very useful  for clinliness.

Also rough handling of the equipment can cause the filter seals to become loose from around the HEPA filter therefore causing leakage and making them unsafe for workers who are counting on them while working in hazardous conditions.

What is a HEPA Filter?

HEPA filters are composed of usually fiberglass fibers randomly arranged. To qualify as HEPA the air filter must remove at least 99.97% of all airborne particles greater than 0.3 micrometers in diameter from the air that passes through it.

what is congestive heart failure?

congestive heart failure: CHF occurs when the heart is unable to pump suffieciently to maintain blood flow to meet the body's needs.

career options and growth of pharmacy profession