SlideShare a Scribd company logo
1 of 14
Hajira Mahmood
Sub topics of NMR
spectroscopy
1. Oversampling
2. Digital filtration
3. Decoupling for
X nuclei
4. Excitation modes
5. Inverse detection
6. Data processing
Oversampling in NMR
Sampling faster than required by the sampling theorem
• effectively increases the dynamic range by a factor of n
• prevents certain sources of noise that are NOT band-limited to same extent as
the systematic NMR signals from being aliased into the spectral window.
• Especially used to alleviate problem while studying large proteins to know
whether typical 16-bit analog-to-digital converter (ADC) has sufficient
dynamic range to digitize the sum of signals as well as a small signal of
interest, even in the presence of excellent solvent suppression.
• Noise in an NMR spectrum consists of analog receiver noise, analog noise
from the analog-to-digital converter components and "quantization noise" due
to the limited precision of vertical digitization decreases by oversampling.
Diagrammatic representation of oversampling
Digital filtration
• In signal processing, digital filter is a system that performs mathematical
operations on a sample discrete-time signal to reduce or to enhance certain
aspects of that signal.
• largely used in signal processing and differs from an analog filter, which is an
electronic circuit working with continuous signals.
• Expensive compared to analog ones, but they can turn many impractical or
impossible designs into possibilities..0
• Digital filters are used for two general purposes
1. For the Separation of signals that have been combined
2. For the restoration of signals that have been distorted in some way.
Analog (electronic) filters can be used for these same tasks; however, digital filters
can achieve far superior results.
Purpose to use digital filters
• A digital filter contains an analog-to-digital converter (ADC), which samples
the signal coming in as input, a microprocessor and some other components for
storing filter coefficients and data.
• There is also a digital-to-analog converter that is present just before the output
stage.
• The software that runs on the microprocessor implements a digital filter by
acting on a number from the ADC and perform mathematical operations.
• can perform several effects such as amplification & delay on the sample
signal
Spin decoupling
Special technique used in NMR spectroscopy to avoid splitting of signals by
eliminating partially of fully observed coupling.
Involves irradiation of proton with sufficiently intense radio frequency energy,
so it prevents the coupling with neighboring proton & gives spectral line as a
singlet.
Helps to determine structure of chemical compounds
Used to simplify a complex NMR spectrum
Possible to irradiate each coupled protons in molecule to produce less complex
spectrum.
It causes multiples to collapse to a doublet or singlet to give easily interrupt
spectra
Important phenomenon used to enhance spectral signals to get clear distinctions
between certain signals
Coupling & decoupling effect
Excitation modes in NMR
• Sample is irradiated with radiofrequency waves of appropriate
frequency
• will excite transitions from the ground to the excited state due to the
interaction of magnetic dipole with the oscillating magnetic field
component of the electromagnetic radiation.
• This excitation field must be orthogonal to the direction of the magnetic
dipoles to generate transitions of the nuclear spin state.
Inverse detection
• This technique become increasingly popular due to software improvements of
spectrometers from one hand and to the increase of sensitivity of the detection
of a X nucleus by the indirect way.
• In fact, it solves the problem of low concentrations.
• Moreover, it allows to reach the NMR parameters such as chemical shifts,
coupling constants & relaxation time spin lattice for nuclei that are impossible
to study by the direct detection.
• arrows figure the magnetization transfer from proton towards 13C and then
from 13C towards the proton.
Excitation modes
Data Acquisition
NMR experiments generally require the co-addition of a number of the nuclear spin
response.
Radiofrequency pulse and receiver phases plays role in it.
The data are recorded as a set of complex numbers which sample NMR signals as a
function of time.
Early Fourier transform spectrometers had limited word length and required some
scaling of the data before co addition, but this is no longer necessary.
The use of DSP gives better filtration of unwanted noise and signals, better effective
ADC resolution, and less baseline distortion.
In two-dimensional (2D) NMR a series of FIDs is acquired using a pulse sequence.
3D and 4D NMR extend the principle to two and three evolution periods respectively,
but time constraints limit the number of samples in each dimension more severely.
Also increase the pressure to use non-uniform sampling of the signal. A very effective
alternative way is to use methods where high resolution is not required
Spectrum Generation
 To make the raw experimental data interpretable they must be converted into a
frequency domain spectrum. The classical, and commonest, method is discrete
Fourier transformation. This is a linear operation. the information content of the
data is unchanged here.
In Fourier processing a weighting function is usually applied to the time
domain data before transformation. After weighting and any zero-filling, the
fast Fourier transform (FFT) algorithm is used to produce the frequency
spectrum. The resultant spectrum consists of a set of complex numbers
sampling.
In 2D NMR, weighting and zero-filling are carried out on the FIDs as normal,
but after Fourier transformation the data matrix is transposed to give a set of
‘inter ferograms.
•

More Related Content

Similar to sub topics of NMR.pptx

Multirate signal processing and decimation interpolation
Multirate signal processing and decimation interpolationMultirate signal processing and decimation interpolation
Multirate signal processing and decimation interpolationransherraj
 
Digital transmission systems
Digital transmission systemsDigital transmission systems
Digital transmission systemsCKSunith1
 
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...IRJET Journal
 
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALS
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALSAN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALS
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALSijmnct
 
Digital Implementation of Costas Loop with Carrier Recovery
Digital Implementation of Costas Loop with Carrier RecoveryDigital Implementation of Costas Loop with Carrier Recovery
Digital Implementation of Costas Loop with Carrier RecoveryIJERD Editor
 
Subsystems of radar and signal processing
Subsystems of radar and signal processing Subsystems of radar and signal processing
Subsystems of radar and signal processing Ronak Vyas
 
Signal denoising techniques
Signal denoising techniquesSignal denoising techniques
Signal denoising techniquesShwetaRevankar4
 
Performance Analysis and Simulation of Decimator for Multirate Applications
Performance Analysis and Simulation of Decimator for Multirate ApplicationsPerformance Analysis and Simulation of Decimator for Multirate Applications
Performance Analysis and Simulation of Decimator for Multirate ApplicationsIJEEE
 
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...IJECEIAES
 
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Yayah Zakaria
 
NASA Fundamental of FSO.pdf
NASA Fundamental of FSO.pdfNASA Fundamental of FSO.pdf
NASA Fundamental of FSO.pdfzoohir
 
Digital signal transmission in ofc
Digital signal transmission in ofcDigital signal transmission in ofc
Digital signal transmission in ofcAnkith Shetty
 
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...IRJET Journal
 
A Survey On Spectrum Sensing Techniques In Cognitive Radio
A Survey On Spectrum Sensing Techniques In Cognitive RadioA Survey On Spectrum Sensing Techniques In Cognitive Radio
A Survey On Spectrum Sensing Techniques In Cognitive RadioJennifer Roman
 
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...theijes
 

Similar to sub topics of NMR.pptx (20)

Multirate signal processing and decimation interpolation
Multirate signal processing and decimation interpolationMultirate signal processing and decimation interpolation
Multirate signal processing and decimation interpolation
 
Digital transmission systems
Digital transmission systemsDigital transmission systems
Digital transmission systems
 
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...
IRJET- Compressed Sensing based Modified Orthogonal Matching Pursuit in DTTV ...
 
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALS
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALSAN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALS
AN OVERVIEW OF PEAK-TO-AVERAGE POWER RATIO REDUCTION TECHNIQUES FOR OFDM SIGNALS
 
Digital Implementation of Costas Loop with Carrier Recovery
Digital Implementation of Costas Loop with Carrier RecoveryDigital Implementation of Costas Loop with Carrier Recovery
Digital Implementation of Costas Loop with Carrier Recovery
 
Es35834838
Es35834838Es35834838
Es35834838
 
L010218691
L010218691L010218691
L010218691
 
Subsystems of radar and signal processing
Subsystems of radar and signal processing Subsystems of radar and signal processing
Subsystems of radar and signal processing
 
Signal denoising techniques
Signal denoising techniquesSignal denoising techniques
Signal denoising techniques
 
NIST_Presentation
NIST_PresentationNIST_Presentation
NIST_Presentation
 
Aj044236240
Aj044236240Aj044236240
Aj044236240
 
Performance Analysis and Simulation of Decimator for Multirate Applications
Performance Analysis and Simulation of Decimator for Multirate ApplicationsPerformance Analysis and Simulation of Decimator for Multirate Applications
Performance Analysis and Simulation of Decimator for Multirate Applications
 
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
 
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...
 
NASA Fundamental of FSO.pdf
NASA Fundamental of FSO.pdfNASA Fundamental of FSO.pdf
NASA Fundamental of FSO.pdf
 
Digital signal transmission in ofc
Digital signal transmission in ofcDigital signal transmission in ofc
Digital signal transmission in ofc
 
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...
IRJET- Dynamic Spectrum Sensing using Matched Filter Method and MATLAB Simula...
 
A Survey On Spectrum Sensing Techniques In Cognitive Radio
A Survey On Spectrum Sensing Techniques In Cognitive RadioA Survey On Spectrum Sensing Techniques In Cognitive Radio
A Survey On Spectrum Sensing Techniques In Cognitive Radio
 
Ei unit 2
Ei unit 2Ei unit 2
Ei unit 2
 
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...
Low Peak to Average Power Ratio and High Spectral Efficiency Using Selective ...
 

More from Hajira Mahmood

Solution chemistry, Moral and Normal solutions
Solution chemistry, Moral and Normal solutionsSolution chemistry, Moral and Normal solutions
Solution chemistry, Moral and Normal solutionsHajira Mahmood
 
A Brief Report on Green Natural Dyes Based on Color Index
A  Brief Report on Green Natural Dyes Based on Color IndexA  Brief Report on Green Natural Dyes Based on Color Index
A Brief Report on Green Natural Dyes Based on Color IndexHajira Mahmood
 
Importance of Paraphrasing in research.pptx
Importance of Paraphrasing in research.pptxImportance of Paraphrasing in research.pptx
Importance of Paraphrasing in research.pptxHajira Mahmood
 
HECk Reaction green vrs conventional.pptx
HECk Reaction green vrs conventional.pptxHECk Reaction green vrs conventional.pptx
HECk Reaction green vrs conventional.pptxHajira Mahmood
 
Microbial fuel cell.pptx
Microbial fuel cell.pptxMicrobial fuel cell.pptx
Microbial fuel cell.pptxHajira Mahmood
 
Tunable Laser (1).pptx
Tunable Laser (1).pptxTunable Laser (1).pptx
Tunable Laser (1).pptxHajira Mahmood
 
sub topics of NMR 2.pptx
sub topics of NMR 2.pptxsub topics of NMR 2.pptx
sub topics of NMR 2.pptxHajira Mahmood
 
Presentation.pptx. Green Chemistry and principal of green Chemistry​
Presentation.pptx. Green Chemistry and principal of green Chemistry​Presentation.pptx. Green Chemistry and principal of green Chemistry​
Presentation.pptx. Green Chemistry and principal of green Chemistry​Hajira Mahmood
 
wound healing (1).pptx
wound healing (1).pptxwound healing (1).pptx
wound healing (1).pptxHajira Mahmood
 
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdf
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdfIon exchange Chromatography as QC ^0 QA in diary Industry.pdf
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdfHajira Mahmood
 

More from Hajira Mahmood (13)

Solution chemistry, Moral and Normal solutions
Solution chemistry, Moral and Normal solutionsSolution chemistry, Moral and Normal solutions
Solution chemistry, Moral and Normal solutions
 
A Brief Report on Green Natural Dyes Based on Color Index
A  Brief Report on Green Natural Dyes Based on Color IndexA  Brief Report on Green Natural Dyes Based on Color Index
A Brief Report on Green Natural Dyes Based on Color Index
 
Importance of Paraphrasing in research.pptx
Importance of Paraphrasing in research.pptxImportance of Paraphrasing in research.pptx
Importance of Paraphrasing in research.pptx
 
Suzuki Reaction.pptx
Suzuki Reaction.pptxSuzuki Reaction.pptx
Suzuki Reaction.pptx
 
HECk Reaction green vrs conventional.pptx
HECk Reaction green vrs conventional.pptxHECk Reaction green vrs conventional.pptx
HECk Reaction green vrs conventional.pptx
 
Microbial fuel cell.pptx
Microbial fuel cell.pptxMicrobial fuel cell.pptx
Microbial fuel cell.pptx
 
Tunable Laser (1).pptx
Tunable Laser (1).pptxTunable Laser (1).pptx
Tunable Laser (1).pptx
 
3.pptxNMR sub topics
3.pptxNMR sub topics 3.pptxNMR sub topics
3.pptxNMR sub topics
 
sub topics of NMR 2.pptx
sub topics of NMR 2.pptxsub topics of NMR 2.pptx
sub topics of NMR 2.pptx
 
Presentation.pptx. Green Chemistry and principal of green Chemistry​
Presentation.pptx. Green Chemistry and principal of green Chemistry​Presentation.pptx. Green Chemistry and principal of green Chemistry​
Presentation.pptx. Green Chemistry and principal of green Chemistry​
 
wound healing (1).pptx
wound healing (1).pptxwound healing (1).pptx
wound healing (1).pptx
 
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdf
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdfIon exchange Chromatography as QC ^0 QA in diary Industry.pdf
Ion exchange Chromatography as QC ^0 QA in diary Industry.pdf
 
Caffeine
CaffeineCaffeine
Caffeine
 

Recently uploaded

Warming the earth and the atmosphere.pptx
Warming the earth and the atmosphere.pptxWarming the earth and the atmosphere.pptx
Warming the earth and the atmosphere.pptxGlendelCaroz
 
GBSN - Biochemistry (Unit 8) Enzymology
GBSN - Biochemistry (Unit 8) EnzymologyGBSN - Biochemistry (Unit 8) Enzymology
GBSN - Biochemistry (Unit 8) EnzymologyAreesha Ahmad
 
Heads-Up Multitasker: CHI 2024 Presentation.pdf
Heads-Up Multitasker: CHI 2024 Presentation.pdfHeads-Up Multitasker: CHI 2024 Presentation.pdf
Heads-Up Multitasker: CHI 2024 Presentation.pdfbyp19971001
 
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.ppt
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.pptGENETICALLY MODIFIED ORGANISM'S PRESENTATION.ppt
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.pptSyedArifMalki
 
Energy is the beat of life irrespective of the domains. ATP- the energy curre...
Energy is the beat of life irrespective of the domains. ATP- the energy curre...Energy is the beat of life irrespective of the domains. ATP- the energy curre...
Energy is the beat of life irrespective of the domains. ATP- the energy curre...Nistarini College, Purulia (W.B) India
 
Vital Signs of Animals Presentation By Aftab Ahmed Rahimoon
Vital Signs of Animals Presentation By Aftab Ahmed RahimoonVital Signs of Animals Presentation By Aftab Ahmed Rahimoon
Vital Signs of Animals Presentation By Aftab Ahmed RahimoonAftabAhmedRahimoon
 
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...kevin8smith
 
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptx
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptxSaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptx
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptxPat (JS) Heslop-Harrison
 
PARENTAL CARE IN FISHES.pptx for 5th sem
PARENTAL CARE IN FISHES.pptx for 5th semPARENTAL CARE IN FISHES.pptx for 5th sem
PARENTAL CARE IN FISHES.pptx for 5th semborkhotudu123
 
NuGOweek 2024 programme final FLYER short.pdf
NuGOweek 2024 programme final FLYER short.pdfNuGOweek 2024 programme final FLYER short.pdf
NuGOweek 2024 programme final FLYER short.pdfpablovgd
 
Precision Farming in Fruit Crops presentation
Precision Farming in Fruit Crops presentationPrecision Farming in Fruit Crops presentation
Precision Farming in Fruit Crops presentationscvns2828
 
Manganese‐RichSandstonesasanIndicatorofAncientOxic LakeWaterConditionsinGale...
Manganese‐RichSandstonesasanIndicatorofAncientOxic  LakeWaterConditionsinGale...Manganese‐RichSandstonesasanIndicatorofAncientOxic  LakeWaterConditionsinGale...
Manganese‐RichSandstonesasanIndicatorofAncientOxic LakeWaterConditionsinGale...Sérgio Sacani
 
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdf
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdfFORENSIC CHEMISTRY ARSON INVESTIGATION.pdf
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdfSuchita Rawat
 
Costs to heap leach gold ore tailings in Karamoja region of Uganda
Costs to heap leach gold ore tailings in Karamoja region of UgandaCosts to heap leach gold ore tailings in Karamoja region of Uganda
Costs to heap leach gold ore tailings in Karamoja region of UgandaTimothyOkuna
 
Electricity and Circuits for Grade 9 students
Electricity and Circuits for Grade 9 studentsElectricity and Circuits for Grade 9 students
Electricity and Circuits for Grade 9 studentslevieagacer
 
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptx
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptxNanoparticles for the Treatment of Alzheimer’s Disease_102718.pptx
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptxssusera4ec7b
 
A Scientific PowerPoint on Albert Einstein
A Scientific PowerPoint on Albert EinsteinA Scientific PowerPoint on Albert Einstein
A Scientific PowerPoint on Albert Einsteinxgamestudios8
 
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENS
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENSANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENS
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENSDr. TATHAGAT KHOBRAGADE
 
EU START PROJECT. START-Newsletter_Issue_4.pdf
EU START PROJECT. START-Newsletter_Issue_4.pdfEU START PROJECT. START-Newsletter_Issue_4.pdf
EU START PROJECT. START-Newsletter_Issue_4.pdfStart Project
 
Taphonomy and Quality of the Fossil Record
Taphonomy and Quality of the  Fossil RecordTaphonomy and Quality of the  Fossil Record
Taphonomy and Quality of the Fossil RecordSangram Sahoo
 

Recently uploaded (20)

Warming the earth and the atmosphere.pptx
Warming the earth and the atmosphere.pptxWarming the earth and the atmosphere.pptx
Warming the earth and the atmosphere.pptx
 
GBSN - Biochemistry (Unit 8) Enzymology
GBSN - Biochemistry (Unit 8) EnzymologyGBSN - Biochemistry (Unit 8) Enzymology
GBSN - Biochemistry (Unit 8) Enzymology
 
Heads-Up Multitasker: CHI 2024 Presentation.pdf
Heads-Up Multitasker: CHI 2024 Presentation.pdfHeads-Up Multitasker: CHI 2024 Presentation.pdf
Heads-Up Multitasker: CHI 2024 Presentation.pdf
 
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.ppt
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.pptGENETICALLY MODIFIED ORGANISM'S PRESENTATION.ppt
GENETICALLY MODIFIED ORGANISM'S PRESENTATION.ppt
 
Energy is the beat of life irrespective of the domains. ATP- the energy curre...
Energy is the beat of life irrespective of the domains. ATP- the energy curre...Energy is the beat of life irrespective of the domains. ATP- the energy curre...
Energy is the beat of life irrespective of the domains. ATP- the energy curre...
 
Vital Signs of Animals Presentation By Aftab Ahmed Rahimoon
Vital Signs of Animals Presentation By Aftab Ahmed RahimoonVital Signs of Animals Presentation By Aftab Ahmed Rahimoon
Vital Signs of Animals Presentation By Aftab Ahmed Rahimoon
 
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...
Harry Coumnas Thinks That Human Teleportation is Possible in Quantum Mechanic...
 
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptx
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptxSaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptx
SaffronCrocusGenomicsThessalonikiOnlineMay2024TalkOnline.pptx
 
PARENTAL CARE IN FISHES.pptx for 5th sem
PARENTAL CARE IN FISHES.pptx for 5th semPARENTAL CARE IN FISHES.pptx for 5th sem
PARENTAL CARE IN FISHES.pptx for 5th sem
 
NuGOweek 2024 programme final FLYER short.pdf
NuGOweek 2024 programme final FLYER short.pdfNuGOweek 2024 programme final FLYER short.pdf
NuGOweek 2024 programme final FLYER short.pdf
 
Precision Farming in Fruit Crops presentation
Precision Farming in Fruit Crops presentationPrecision Farming in Fruit Crops presentation
Precision Farming in Fruit Crops presentation
 
Manganese‐RichSandstonesasanIndicatorofAncientOxic LakeWaterConditionsinGale...
Manganese‐RichSandstonesasanIndicatorofAncientOxic  LakeWaterConditionsinGale...Manganese‐RichSandstonesasanIndicatorofAncientOxic  LakeWaterConditionsinGale...
Manganese‐RichSandstonesasanIndicatorofAncientOxic LakeWaterConditionsinGale...
 
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdf
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdfFORENSIC CHEMISTRY ARSON INVESTIGATION.pdf
FORENSIC CHEMISTRY ARSON INVESTIGATION.pdf
 
Costs to heap leach gold ore tailings in Karamoja region of Uganda
Costs to heap leach gold ore tailings in Karamoja region of UgandaCosts to heap leach gold ore tailings in Karamoja region of Uganda
Costs to heap leach gold ore tailings in Karamoja region of Uganda
 
Electricity and Circuits for Grade 9 students
Electricity and Circuits for Grade 9 studentsElectricity and Circuits for Grade 9 students
Electricity and Circuits for Grade 9 students
 
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptx
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptxNanoparticles for the Treatment of Alzheimer’s Disease_102718.pptx
Nanoparticles for the Treatment of Alzheimer’s Disease_102718.pptx
 
A Scientific PowerPoint on Albert Einstein
A Scientific PowerPoint on Albert EinsteinA Scientific PowerPoint on Albert Einstein
A Scientific PowerPoint on Albert Einstein
 
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENS
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENSANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENS
ANITINUTRITION FACTOR GYLCOSIDES SAPONINS CYANODENS
 
EU START PROJECT. START-Newsletter_Issue_4.pdf
EU START PROJECT. START-Newsletter_Issue_4.pdfEU START PROJECT. START-Newsletter_Issue_4.pdf
EU START PROJECT. START-Newsletter_Issue_4.pdf
 
Taphonomy and Quality of the Fossil Record
Taphonomy and Quality of the  Fossil RecordTaphonomy and Quality of the  Fossil Record
Taphonomy and Quality of the Fossil Record
 

sub topics of NMR.pptx

  • 1.
  • 2. Hajira Mahmood Sub topics of NMR spectroscopy 1. Oversampling 2. Digital filtration 3. Decoupling for X nuclei 4. Excitation modes 5. Inverse detection 6. Data processing
  • 3. Oversampling in NMR Sampling faster than required by the sampling theorem • effectively increases the dynamic range by a factor of n • prevents certain sources of noise that are NOT band-limited to same extent as the systematic NMR signals from being aliased into the spectral window. • Especially used to alleviate problem while studying large proteins to know whether typical 16-bit analog-to-digital converter (ADC) has sufficient dynamic range to digitize the sum of signals as well as a small signal of interest, even in the presence of excellent solvent suppression. • Noise in an NMR spectrum consists of analog receiver noise, analog noise from the analog-to-digital converter components and "quantization noise" due to the limited precision of vertical digitization decreases by oversampling.
  • 5. Digital filtration • In signal processing, digital filter is a system that performs mathematical operations on a sample discrete-time signal to reduce or to enhance certain aspects of that signal. • largely used in signal processing and differs from an analog filter, which is an electronic circuit working with continuous signals. • Expensive compared to analog ones, but they can turn many impractical or impossible designs into possibilities..0 • Digital filters are used for two general purposes 1. For the Separation of signals that have been combined 2. For the restoration of signals that have been distorted in some way. Analog (electronic) filters can be used for these same tasks; however, digital filters can achieve far superior results.
  • 6. Purpose to use digital filters • A digital filter contains an analog-to-digital converter (ADC), which samples the signal coming in as input, a microprocessor and some other components for storing filter coefficients and data. • There is also a digital-to-analog converter that is present just before the output stage. • The software that runs on the microprocessor implements a digital filter by acting on a number from the ADC and perform mathematical operations. • can perform several effects such as amplification & delay on the sample signal
  • 7. Spin decoupling Special technique used in NMR spectroscopy to avoid splitting of signals by eliminating partially of fully observed coupling. Involves irradiation of proton with sufficiently intense radio frequency energy, so it prevents the coupling with neighboring proton & gives spectral line as a singlet. Helps to determine structure of chemical compounds Used to simplify a complex NMR spectrum Possible to irradiate each coupled protons in molecule to produce less complex spectrum. It causes multiples to collapse to a doublet or singlet to give easily interrupt spectra Important phenomenon used to enhance spectral signals to get clear distinctions between certain signals
  • 9. Excitation modes in NMR • Sample is irradiated with radiofrequency waves of appropriate frequency • will excite transitions from the ground to the excited state due to the interaction of magnetic dipole with the oscillating magnetic field component of the electromagnetic radiation. • This excitation field must be orthogonal to the direction of the magnetic dipoles to generate transitions of the nuclear spin state.
  • 10. Inverse detection • This technique become increasingly popular due to software improvements of spectrometers from one hand and to the increase of sensitivity of the detection of a X nucleus by the indirect way. • In fact, it solves the problem of low concentrations. • Moreover, it allows to reach the NMR parameters such as chemical shifts, coupling constants & relaxation time spin lattice for nuclei that are impossible to study by the direct detection. • arrows figure the magnetization transfer from proton towards 13C and then from 13C towards the proton.
  • 12. Data Acquisition NMR experiments generally require the co-addition of a number of the nuclear spin response. Radiofrequency pulse and receiver phases plays role in it. The data are recorded as a set of complex numbers which sample NMR signals as a function of time. Early Fourier transform spectrometers had limited word length and required some scaling of the data before co addition, but this is no longer necessary. The use of DSP gives better filtration of unwanted noise and signals, better effective ADC resolution, and less baseline distortion. In two-dimensional (2D) NMR a series of FIDs is acquired using a pulse sequence. 3D and 4D NMR extend the principle to two and three evolution periods respectively, but time constraints limit the number of samples in each dimension more severely. Also increase the pressure to use non-uniform sampling of the signal. A very effective alternative way is to use methods where high resolution is not required
  • 13. Spectrum Generation  To make the raw experimental data interpretable they must be converted into a frequency domain spectrum. The classical, and commonest, method is discrete Fourier transformation. This is a linear operation. the information content of the data is unchanged here. In Fourier processing a weighting function is usually applied to the time domain data before transformation. After weighting and any zero-filling, the fast Fourier transform (FFT) algorithm is used to produce the frequency spectrum. The resultant spectrum consists of a set of complex numbers sampling. In 2D NMR, weighting and zero-filling are carried out on the FIDs as normal, but after Fourier transformation the data matrix is transposed to give a set of ‘inter ferograms.
  • 14.