Theory and Principle of FTIR head points:
What is Infrared Region?
Infrared Spectroscopy
What is FTIR?
Superiority of FTIR
FTIR optical system diagram
sampling techniques
The sample analysis process
advantage of FTIR
References
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
An Infrared spectrum represents a fingerprint of a sample with absorption peaks which correspond to the frequencies of vibrations between the bonds of the atoms making up the material-Because each different material is a unique combination of atoms, no two compounds produce the exact same spectrum, therefore IR can result in a unique identification of every different kind of material!
A method of obtaining an Infrared spectrum by measuring the interferogram of a sample using an interferometer, then performing a Fourier Transform upon the interferogram to obtain the spectrum.
Fourier transform infrared spectroscopy: advantage and disadvantage of conventional infrared spectroscopy, introduction to FTIR ,principle of FTIR, working, advantage, disadvantage and application of FTIR.
An Infrared spectrum represents a fingerprint of a sample with absorption peaks which correspond to the frequencies of vibrations between the bonds of the atoms making up the material-Because each different material is a unique combination of atoms, no two compounds produce the exact same spectrum, therefore IR can result in a unique identification of every different kind of material!
A method of obtaining an Infrared spectrum by measuring the interferogram of a sample using an interferometer, then performing a Fourier Transform upon the interferogram to obtain the spectrum.
Fourier transform infrared spectroscopy: advantage and disadvantage of conventional infrared spectroscopy, introduction to FTIR ,principle of FTIR, working, advantage, disadvantage and application of FTIR.
Fourier Transform Infrared Spectroscopy-:A type of infrared spectroscopy.It is method of obtaining an infrared spectrum by measuring interferogram and then performimg a Fourier Transform upon the interferogram to obtain the spectrum.
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
describes the complete history, mechanisms, instrumentation(jablonski diagram), types, comparision and factors affecting, applications of fluorescence and phosphorescence and describes about quenching and stokes shift.
Presenting a topic which is entitled: Detectors
Above topic includes:
Types of detector
phototube detector
photomultiplier tubes
silicon photodiodes
photovoltaic cells
advantages
multi-channel photon detectors
linear photodiode arrays
photodiode array
with basics of instrumentation and science technology
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Its a theoretical content for Pharmacy graduates, post graduates in pharmacy and Doctor of Pharmacy And also M Sc Instrumentation, UG and PG of Ayurveda medical students, MS etc.
In this slide contains Principle, Methods, Interpretation and applications of XRD.
Presented by: Udit Narayan Singh (Department of pharmaceutics)
RIPER, anantpur.
Fourier Transform Infrared Spectroscopy-:A type of infrared spectroscopy.It is method of obtaining an infrared spectrum by measuring interferogram and then performimg a Fourier Transform upon the interferogram to obtain the spectrum.
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
describes the complete history, mechanisms, instrumentation(jablonski diagram), types, comparision and factors affecting, applications of fluorescence and phosphorescence and describes about quenching and stokes shift.
Presenting a topic which is entitled: Detectors
Above topic includes:
Types of detector
phototube detector
photomultiplier tubes
silicon photodiodes
photovoltaic cells
advantages
multi-channel photon detectors
linear photodiode arrays
photodiode array
with basics of instrumentation and science technology
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Its a theoretical content for Pharmacy graduates, post graduates in pharmacy and Doctor of Pharmacy And also M Sc Instrumentation, UG and PG of Ayurveda medical students, MS etc.
In this slide contains Principle, Methods, Interpretation and applications of XRD.
Presented by: Udit Narayan Singh (Department of pharmaceutics)
RIPER, anantpur.
Fourier Transform Infrared Spectrometry (FTIR) and TextileAzmir Latif Beg
Fourier-transform infrared spectroscopy (FTIR) is a technique used to obtain an infrared spectrum of absorption or emission of a solid, liquid or gas. FTIR offers quantitative and qualitative analysis for organic and inorganic samples. Fourier Transform Infrared Spectroscopy (FTIR) identifies chemical bonds in fiber. By FTIR we only know the name of fiber is identified. By this technique we can identify the exact composition of fiber like 80 % polyester 20 % cotton.
High performance liquid chromatography (HPLC) head points:
HPLC Advantages Vs GC
Instrumentation
HPLC System
Separations
Mobile Phase Reservoirs
Degasser
Aim of Gradient system
High/Low pressure gradient system
HPLC Pump Criteria
HPLC Pumps: Types
Reciprocating Pumps
Sample introduction
Manual Injector
Auto Injector
HPLC Modes
The Mobile Phase
Hydrophobic interaction
Common reverse phase solvents
Detectors
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Gas chromatography head points:
Invention of Chromatography
original chromatography Experiment
Common types of chromatography
Paper and Thin layer chromatography
How does chromatography work?
Theoretical Plate
gas chromatography
schematic of GC
carrier gas-supply
Injection port
sample Injection system
split/spitless Injection
sample valves
GC columns
open tubular columns
Temperature Control
Solid Support Materials
Particle size of Supports
The stationary Phase
Detection systems
Characteristics of the Ideal Detector
Flame Ionization Detectors
Thermal Conductivity Detector
Electron-capture Detectors
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Scanning Probe microscopy (AFM and STM) head point
AFM: Configuration of AFM
Parts of AFM system and Principle of AFM
Three Modes of AFM
AFM Instrument
Advantage and disadvantage
STM
Schematic Diagram
AFM and STM
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
X-Ray Diffraction head points:
Introduction
History
How Diffraction Works
Demonstration
Analyzing Diffraction Patterns
Solving DNA
Applications
Summary and Conclusions
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Photovoltaics: Fundamental Concepts and novel systems
Energy levels -bands
Doping of semiconductors
Energy band alignments between different phases
Space charge layers
p-n junctions, Schottky barriers
p-n cells, Si cells, thin film cells
Schottky cells (solid and liquid junction)
p-i-n cells
Fundamental limits of photovoltaic cells
How to overcome/ bypass these limits
New generation cells (brief survey)
PV stability, efficiencies and economics
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
What is Automobile??
Brief History of Automobile
Changes over the years...
Indian Automobile Industry
Main parts of an Automobile
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Nanoimprint Lithography head points:
Approaches: thermal and UV NIL
Properties of NIL
Overview. of NIL
Thermal NIL resists.
Residual layer after NIL.
NIL for large features (more difficult than small one).
Room temperature NIL, reverse NIL, inking.
NIL of bulk resist (polymer sheet, pellets).
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Presenting a topic based on introduction to nanoscience and nanotechnology.
what is nano?
certain nomenclature like nanotechnology, nanoscience, nanomaterial, nanoscale, nanometer and so on.
surface to volume ratio and quantum effect related concepts.
future applications.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Top down and bottom up method, processing, flow chart of top down and bottom up approach, Application.
I hope this presentation helpful for you.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Different types of Nanolithography technique.
Types: Electron beam lithography, Photolithography, electron-beam writing, ion- lithography, X-ray lithography, and related images, concepts and graphical views.
I hope this presentation helpful for you.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Infrared Spectroscopy and UV-Visible spectroscopyPreeti Choudhary
Instrumentation of Infrared Spectroscopy and UV-Vis spectroscopy
Discuss the fundamentals and concepts behind Infrared and UV-Vis spectroscopy.
I hope this presentation helpful for you.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Presenting a presentation on the topic of Column chromatography with including basics of chromatography, principles, equations, graphs and data related to it.
Topics which covered in this ppt is
Principle of chromatography
classification of chromatography
partition coefficient
chromatogram
Resolution
plate theory
determination of N
band zone broadening
rate theory
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Column Chromatography: basics of chromatography and principle of chromatography, Classification, partition coefficient , chromatogram, retention time and volume, capacity and selectivity factors, plate theory, band broadening, rate theory, mass transfer, packed GLC column, open tubular column capillary columns, liquid chromatography column resolution.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Operational amplifier: inverting and non-inverting amplifier, Power bandwidth, slew rate: slew rate distortion, noise gain, band width product. cascade amplifiers- bandwidth, CMRR, PSRR, Open loop op amp characteristics.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
Theory of NMR, nuclear magnetic resonance, instrumentation, solvents, chemical shift, photon NMR, spin coupling, coupling constant and applications.
https://www.linkedin.com/in/preeti-choudhary-266414182/
https://www.instagram.com/chaudharypreeti1997/
https://www.facebook.com/profile.php?id=100013419194533
https://twitter.com/preetic27018281
Please like, share, comment and follow.
stay connected
If any query then contact:
chaudharypreeti1997@gmail.com
Thanking-You
Preeti Choudhary
The increased availability of biomedical data, particularly in the public domain, offers the opportunity to better understand human health and to develop effective therapeutics for a wide range of unmet medical needs. However, data scientists remain stymied by the fact that data remain hard to find and to productively reuse because data and their metadata i) are wholly inaccessible, ii) are in non-standard or incompatible representations, iii) do not conform to community standards, and iv) have unclear or highly restricted terms and conditions that preclude legitimate reuse. These limitations require a rethink on data can be made machine and AI-ready - the key motivation behind the FAIR Guiding Principles. Concurrently, while recent efforts have explored the use of deep learning to fuse disparate data into predictive models for a wide range of biomedical applications, these models often fail even when the correct answer is already known, and fail to explain individual predictions in terms that data scientists can appreciate. These limitations suggest that new methods to produce practical artificial intelligence are still needed.
In this talk, I will discuss our work in (1) building an integrative knowledge infrastructure to prepare FAIR and "AI-ready" data and services along with (2) neurosymbolic AI methods to improve the quality of predictions and to generate plausible explanations. Attention is given to standards, platforms, and methods to wrangle knowledge into simple, but effective semantic and latent representations, and to make these available into standards-compliant and discoverable interfaces that can be used in model building, validation, and explanation. Our work, and those of others in the field, creates a baseline for building trustworthy and easy to deploy AI models in biomedicine.
Bio
Dr. Michel Dumontier is the Distinguished Professor of Data Science at Maastricht University, founder and executive director of the Institute of Data Science, and co-founder of the FAIR (Findable, Accessible, Interoperable and Reusable) data principles. His research explores socio-technological approaches for responsible discovery science, which includes collaborative multi-modal knowledge graphs, privacy-preserving distributed data mining, and AI methods for drug discovery and personalized medicine. His work is supported through the Dutch National Research Agenda, the Netherlands Organisation for Scientific Research, Horizon Europe, the European Open Science Cloud, the US National Institutes of Health, and a Marie-Curie Innovative Training Network. He is the editor-in-chief for the journal Data Science and is internationally recognized for his contributions in bioinformatics, biomedical informatics, and semantic technologies including ontologies and linked data.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
1. PRESENTED BY:- Preeti Choudhary
MSc (Applied Physics)
chaudharypreeti1997@gmail.com
Theory and principle of
FTIR
2. What is Infrared Region?
Infrared radiation lies between the visible and
microwave portions of the electromagneticspectrum.
Infrared waves have wavelengths longer than visible
and shorter than microwaves, and have frequencies
which are lower than visible and higher than
microwaves.
The Infrared region is divided into: near, mid and far-
infrared.
Near-infrared refers to the part of the infrared
spectrum that is closest to visible light and far-
infrared refers to the part that is closer to the
microwave region.
Mid-infrared is the region between these two.
3. The primary source of infrared radiation is thermal
radiation. (heat)
It is the radiation produced by the motion of atoms and
molecules in an object. The higher the temperature, the
more the atoms and molecules move and the more
infrared radiation they produce.
Any object radiates in the infrared. Even an ice cube,
emits infrared.
4. According to Principle ofIR,
Molecular Vibration takes place as a result
of Absorption of IR radiation when –
Applied Infrared Frequency = Natural frequency of vibration
•Every bond or functional groups requires different frequency
for Absorption. Hence characteristics Peak is observed for
every functional group or part of the molecule.
5. Infrared Spectroscopy
For isopropyl alcohol, CH(CH3)2OH, the infrared
absorption bands identify the various functional groups
of the molecule.
7. FT-IR stands for Fourier Transform Infrared, the
preferred method of infrared spectroscopy. In infrared
spectroscopy, IR radiation is passed through a sample.
Some of the infrared radiation is absorbed by the sample
and some of it is passed through (transmitted).
The resulting spectrum represents the molecular absorption
and transmission, creating a molecular fingerprint of the
sample.
Like a fingerprint no two unique molecular structures produce
the same infrared spectrum. This makes infrared
spectroscopy useful for several types of analysis.
8. So,what informationcan FT-IR provide?
It can identify unknown materials
It can determine the quality or consistency of a
sample
It can determine the amount of components in a
mixture
9. Superiority of FT-IR
Dispersive infrared spectrometers suffer from several
disadvantages in sensitivity, speed and wavelength
accuracy. Most of the light from the source does not in fact
pass through the sample to the detector, but is lost in the
narrowness of the focusing slits; only poor sensitivity
results. Since the spectrum takes minutes to record, the
method cannot be applied to fast processes.
Dispersive infrared spectrometers scan over the
wavelength range and disperse the light by use of a
grating, these spectrometers suffer from wavelength
inaccuracies associated with the backlash in the mechanical
movements, such as in the rotation of mirrors and
gratings.
An entirely different principle is involved in Fourier
Transform infrared spectroscopy, which centres on a
Michelson interferometer, so that the method can also be
called interferometric infrared spectroscopy.
10. Fourier transform infrared spectroscopyis preferred
over dispersive or filter methods of infrared spectral
analysis for several reasons:
• It is a non-destructive technique.
• It provides a precise measurement method which
requires no external calibration.
• It can increase speed, collecting a scan every second.
• It can increase sensitivity.
• It has greater optical throughput.
• It is mechanically simple with only one moving part.
11. Toseparate IRlight, a grating isused.
Grating
Light source
Detector
Sample
Slit
Toselect the specified IRlight,
A slit isused.
Fixed CCM
B.S.
Moving CCM
IRLightsource
Sample
Detector
An interferogram is first made
by the interferometer using IR
light.
The interferogram is calculated and transformed
into a spectrum using a Fourier Transform (FT).
12. Dispersive Spectrometer FTIR
In order to measure an IR
spectrum,
the dispersion Spectrometer
takesseveral minutes.
Also the detector receives
only a few % of the energy
of original light source.
In order to measure an IR
spectrum,
FTIR takes only a few
seconds.
Moreover, the detector
receives up to 50% of the
energy of original light
source. (much larger than
the dispersion
spectrometer.)
13. THEORY OF FT-IR:
Fourier Transform Infrared (FT-IR) spectrometry was
developed in order to overcome the limitations encountered
with dispersive instruments.
The main difficulty was the slow scanning process. A
method for measuring all of the infrared frequencies
simultaneously, rather than individually, was needed.
A solution was developed which employed a very simple
optical device called an interferometer. The interferometer
produces a unique type of signal which has all of the infrared
frequencies “encoded” into it.
The signal can be measured very quickly, usually on the
order of one second or so. Thus, the time element per sample is
reduced to a matter of a few seconds rather than several
minutes.
14. Most interferometers employ a beamsplitter which takes
the incoming infrared beam and divides it into two optical
beams.
One beam reflects off of a flat mirror which is fixed in
place. The other beam reflects off of a flat mirror which is on a
mechanism which allows this mirror to move a very short
distance (typically a few millimeters) away from the
beamsplitter.
The two beams reflect off of their respective mirrors and
are recombined when they meet back at the beamsplitter.
Because the path that one beam travels is a fixed length and
the other is constantly changing as its mirror moves, the
signal which exits the interferometer is the result of these two
beams “interfering” with eachother.
The resulting signal is called an interferogram which
has the unique property that every data point (a function of
the moving mirror position) which makes up the signal has
information about every infrared frequency which comes
from the source.
15.
16.
17. This means that as the interferogram is measured, all
frequencies are being measured simultaneously. Thus, the
use of the interferometer results in extremely fast
measurements.
Because the analyst requires a frequency spectrum (a
plot of the intensity at each individual frequency) in order
to make an identification, the measured interferogram
signal can not be interpreted directly.
A means of “decoding” the individual frequencies is
required. This can be accomplished via a well-known
mathematical technique called the Fourier transformation.
This transformation is performed by the computer which
then presents the user with the desired spectral
information for analysis.
18. SAMPLING TECHNIQUES
1.Liquid Samples:
Neat sample
Diluted solution
Liquid cell
2.Solid Samples:
Neat sample
Cast films
Pressed films
KBr pellets
Mull
3.Gas Samples:
Short path cell
Long path cell
19. The Sample Analysis Process:
The normal instrumental process is as follows:
1.The Source: Infrared energy is emitted from a glowing black-
body source. This beam passes through an aperture which
controls the amount of energy presented to the sample (and,
ultimately, to the detector).
2.The Interferometer: The beam enters the interferometer where
the “spectral encoding” takesplace. The resulting interferogram
signal then exits the interferometer.
3.TheSample:The beam enters the sample compartment where
it is transmitted through or reflected off of the surface of the
sample, depending on the type of analysis being accomplished.
This is where specific frequencies of energy, which are
uniquely characteristic of the sample, are absorbed.
4.The Detector: The beam finally passes to the detector for final
measurement. The detectors used are specially designed to
measure the special interferogram signal.
20. 5.The Computer: The measured signal is digitized and sent to
the computer where the Fourier transformation takes place.
The final infrared spectrum is then presented to the user for
interpretation and any furthermanipulation.
Because there needs to be a relative scale for the
absorption intensity, a background spectrum must also be
measured. This is normally a measurement with no sample in
the beam. This can be compared to the measurement with the
sample in the beam to determine the “percent transmittance.”
This technique results in a spectrum which has all of the
instrumental characteristics removed.
Thus, all spectral features which are present are
strictly due to the sample. A single background measurement
can be used for many sample measurements because this
spectrumis characteristic of the instrument itself.
21.
22. Advantages of FT-IR
•Speed: Because all of the frequencies are measured
simultaneously, most measurements by FT-IR are made in a
matter of seconds rather than several minutes.
•Sensitivity: Sensitivity is dramatically improved with FT-IR
for many reasons. The detectors employed are much more
sensitive, the optical throughput is much higher which results
in much lower noise levels, and the fast scans enable the co
addition of several scans in order to reduce the random
measurement noise to any desired level (referred to as signal
averaging).
•Mechanical Simplicity: The moving mirror in the
interferometer is the only continuously moving part in the
instrument. Thus, there is very little possibility of mechanical
breakdown.
23. • Internally Calibrated: These instruments employ a HeNe
laser as an internal wavelength calibration standard.
These instruments are self-calibrating and never need to
be calibrated by the user.
24. REFERENCES :-
• Introduction to Fourier Transform Infrared Spectrometry By
Thermo Nicolet Corporation
• An article onFTIR SAMPLING TECHNIQUES by Hue Phan.
TN.101
• Instrumental Methods Of Chemical Analysis by Gurdeep R.
Chatwal & Sham K.Anand
• P. R. Griffiths and J. A. de Haseth, Fourier-Transform Infrared
Spectroscopy, Wiley- Interscience, New York,
Chichester,Brisbane, Toronto, Singapore,1986
• FTIR Spectroscopy By Jorge. E. Perez and Richard T. Meyer
CIC
•Photonics, Inc. 3825 Osuna Rd. NE Ste. 6 & 7. Albuquerque,
NM 87105.