The document summarizes the principles and applications of cavity ring down spectroscopy (CRDS). It describes how CRDS works by using an optical cavity to greatly increase the effective path length of light, enabling precise measurements of weak absorptions. Key applications mentioned include environmental monitoring, emissions monitoring, and trace gas analysis.
Electron Spin Resonance (ESR) SpectroscopyHaris Saleem
Electron Spin Resonance Spectroscopy
Also called EPR Spectroscopy
Electron Paramagnetic Resonance Spectroscopy
Non-destructive technique
Applications
Extensively used in transition metal complexes
Deviated geometries in crystals
Photoelectron spectroscopy
- a single photon in/ electron out process
• X-ray Photoelectron Spectroscopy (XPS)
- using soft x-ray (200-2000 eV) radiation to
examine core-levels.
• Ultraviolet Photoelectron Spectroscopy (UPS)
- using vacuum UV (10-45 eV) radiation to
examine valence levels.
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
Photoluminescence Spectroscopy for studying Electron-Hole pair recombination ...RunjhunDutta
Description of Photoluminescence Spectroscopy: Principle, Instrumentation & Application.
Three research papers have been summarized which lay stress on Photoluminescence Study for Electron-Hole Pair Recombination for characterizing the properties of semiconductors used in Photoelectrochemical Splitting of Water.
Instrumentation presentation - Auger Electron Spectroscopy (AES)Amirah Basir
Group 5-AES
Normaizatul Hanissa Binti Hamdan
Amirah Binti Basir
-Introduction/Backgroud /History, fundamental/basic principle and
elaboration of the principle, related pictures, related
equations/expressions/derivations, components and it functions,
related models/brands, technologies and applications
Introduction to Activation analysis using Neutron
Baisc Principle of NAA
Instrumental NAA
Characteristics of INAA
Advantages, Limitation and Applications of INNA
Electron Spin Resonance (ESR) SpectroscopyHaris Saleem
Electron Spin Resonance Spectroscopy
Also called EPR Spectroscopy
Electron Paramagnetic Resonance Spectroscopy
Non-destructive technique
Applications
Extensively used in transition metal complexes
Deviated geometries in crystals
Photoelectron spectroscopy
- a single photon in/ electron out process
• X-ray Photoelectron Spectroscopy (XPS)
- using soft x-ray (200-2000 eV) radiation to
examine core-levels.
• Ultraviolet Photoelectron Spectroscopy (UPS)
- using vacuum UV (10-45 eV) radiation to
examine valence levels.
It contains the basic principle of Mossbauer Spectroscopy.
Recoil energy, Dopler shift.
The instrumentation of Mossbauer Spectroscopy.
Hyperfine interactions.
Photoluminescence Spectroscopy for studying Electron-Hole pair recombination ...RunjhunDutta
Description of Photoluminescence Spectroscopy: Principle, Instrumentation & Application.
Three research papers have been summarized which lay stress on Photoluminescence Study for Electron-Hole Pair Recombination for characterizing the properties of semiconductors used in Photoelectrochemical Splitting of Water.
Instrumentation presentation - Auger Electron Spectroscopy (AES)Amirah Basir
Group 5-AES
Normaizatul Hanissa Binti Hamdan
Amirah Binti Basir
-Introduction/Backgroud /History, fundamental/basic principle and
elaboration of the principle, related pictures, related
equations/expressions/derivations, components and it functions,
related models/brands, technologies and applications
Introduction to Activation analysis using Neutron
Baisc Principle of NAA
Instrumental NAA
Characteristics of INAA
Advantages, Limitation and Applications of INNA
A Health & Wellness Approach to Enterprise Process ManagementBrett Champlin
Don’t just fix the problems; fix the process (treat the disease, not just the symptoms). Don’t just fix the process; fix the business (treat the patient, not just the disease). Not being “sick” or in pain doesn’t mean you are healthy or will stay healthy without a wellness plan. The same thing applies to our business processes and we need to have a “wellness plan” that monitors our processes to maintain a healthy business.
Picarro Combustion Module Cavity Ring Down Spectroscopy Stable Isotope AnalysisPicarro
Picarro's Combustion Module - Cavity Ring-Down Spectroscopy (CRDS) platform can run automated stable isotope sampling for Carbon 13 for as long as five hours without interruption. This is dramatic improvement in cost and ease of use of traditional IRMS. Read about the technology at www.picarro.com
Picarro - A Revolution in Food Safety and Food Fraud DetectionPicarro
Picarro makes the worlds highest performing and easiest to use gas analyzers. Picarro analyzers are revolutionizing the way the farmers, grocers, distributors, and regulators trace where food comes from, identify point of origin, and screen for food fraud and adulteration. Visibility into the authenticity and origin of the food we eat is becoming increasingly important in an era of globalized food distribution.
Extraction of Heavy Metals From Industrial Waste WaterHashim Khan
This was my topic of research during Bachelors. I made this presentation to give a brief overview of what apparatus i used and the methodologies of my experimentation.
Spectroscopy techniques, it's principle, types and applications NizadSultana
Spectroscopy and it's applications as well as it's types like Infrared spectroscopy and ultraviolet spectroscopy and principle of spectroscopy why we use spectroscopy.
IR SPECTROSCOPY-INTRODUCTION, PRINCIPLE, TYPE OF VIBRATIONS, INSTRUMENTATION, APPLICATION{ FOR the m.pharm 1st year 2019
Presented by DIPSANKAR BERA(M.PHARM STUDENT)
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
5. The term "laser" originated as an acronym for “Light Amplification by Stimulated Emission of Radiation.
E1 < E2 < E3; that is, the energy of level 2 lies between that of the ground state and level 3.
The pump source provides energy to the laser system.
Initially, the system of atoms is at thermal equilibrium, and the majority of the atoms will be in the ground state, i.e., N1 ≈ N, N2 ≈ N3 ≈ 0.
If we continue pumping the atoms, we will excite an appreciable number of them into level 3, such that N3 > 0. These excited atoms to quickly decay to level 2.
An atom in level 2 may decay by spontaneous emission to the ground state, releasing a photon of frequency ν12 given by E2 –E1 = hν12.
If the lifetime of this transition, τ21 >> τ32 , a population inversion (N2 > N1 ) has thus been achieved between level 1 and 2, and optical amplification at the frequency ν21 can be obtained.
10. Typical experimental set-up of pulsed CRDS based on O’Keefe and Deacon design.
Mirror reflectometerof Anderson et al. : Instead of measuring the phase shift, the intensity decay of the cavity is measured after the light is quickly shut off with a Pockelscell.
J. J. Scherer, Chem. Rev. 1997, 97, 25-51
14. If the only loss process for light is leakage through the mirrors, the ring down is characterized by
tr-roundtrip time for light in the cavity
R -mirror reflectivity
Lopt-distance between the two mirrors
c -speed of light
T0 -1/e decay time of the light ( ring down lifetime).
A -absorbance
I0 -initial light intensity
I -transmitted light intensity
σ-absorption cross section
Labs -path length of light through the absorber
N -number density of absorber molecules (per unit volume).
15. The absorbance can be calculated by the equation :
Sprague et al.,31 Copyright 2012 American Chemical Society
16. For molecules with small cross sections or for trace gases , a detectable absorbance can be attained by two methods :
•Increasing the concentration of absorber molecules
•Or by increasing the physical absorption path length using long pass absorption spectroscopy.
Eric Corosson, www.picarro.com
Some of the most popular absorption spectroscopy techniques :
•Laser-Induced Fluorescence (LIF)
•Resonance enhanced MultiphotonIonization (REMPI)
•PhotoacousticSpectroscopy (PAS)
These three methods are all sensitive laser-based methods, which ‘indirectly’ measure absorption features of the analyte. In other words, some other physical phenomenon (fluorescence, ionization, and pressure waves, respectively) are detected and then related back to absorption in each of these methods.
WHY DO WE NEED A NEW TECHNIQUE ?
18. Isotope-ratio mass spectrometry (IRMS) is a specialization of mass spectrometry, in which mass spectrometric methods are used to measure the relative abundance of isotopes in a given sample .
In the most general terms the instrument operates by ionizing the sample of interest, accelerating it over a potential in the kilo-volt range, and separating the resulting stream of ions according to their mass-to-charge ratio (m/z). Beams with lighter ions bend at a smaller radius than beams with heavier ions. The current of each ion beam is then measured using a 'Faraday cup' or multiplier detector.
ISOTOPE-RATIO MASS SPECTROMETRY (IRMS)
Not suitable for field measurements.
19. Carbon isotope ratios are usually expressed in parts per thousand (or per mil, ‰) relative to a standard, using the common notation
ä13C = [(Rsample–Rstandard) /Rstandard]x 1000
where
R =13C/12C
is the ratio of the heavier to the lighter stable isotope of carbon. The common reference for ä13C was obtained from a cretaceous marine fossil, Belemnitella americana, from the Pee Dee formation in South Carolina.
This material had an anomalously high 13C:12C ratio (0.0112372), and was established as δ13C value of zero. All original supplies of PDB have been essentially exhausted and replaced by secondary carbonate standards calibrated against those prepared by the U.S. National
Institute of Standards and Technology (NIST) .
20. Determination of 13C/12C for Carbon Dioxide in Human Breath
Breath tests based on ä13C were used to assess liver
function and disease, gastric emptying, bacterial
overgrowth, and pancreatic function.
H. pylori,14 is the leading cause of ulcers. It is estimated
that about two-thirds of the world’s population has H.
pylori. 5 The test is based on the absence of urease in the
healthy human gastrointestinal tract. Individuals having H.
pylori will exhibit an increase in the concentration of
13CO2 in their breath following ingestion of the 13C-labeled
urea.
H. Pylori has a high urease activity, and converts urea
(CO(NH2)2) into HCO3- and NH4+. The HCO3- finds its way
through the blood stream to the lungs and is exhaled as
CO2. Hence, Results are reported as the difference over
baseline (DOB).
A DOB value less than 2-3 generally indicates the absence of H. pylori whereas a DOB value greater
than 2-3 is strongly associated with the presence of H. pylori.
21. The output of a tunableexternal-cavity diode passes through an isolator, preventing back reflections from reaching the diode laser. The beam is then focused into an acoustoopticmodulator (AOM) capable of rapidly deflecting the beam from the optical cavity. Following the AOM, a beam splitter directs a small fraction of the laser radiation onto an etalon used to precisely measure the wavelength of the laser radiation. The remaining light passes though mode-matching optics before coupling into a three-mirror high-finesse ring-down cavity (RDC).
Analytical Chemistry, Vol. 74, No. 9, May 1, 2002 2007
INSRUMENTATION
22. The two absorption features chosen to measure the
relative abundances of 12C16O16O and 13C16O16O
arise from different rotational/vibrational transitions of
the CO2 molecule (R(62) line of the 12C16O16O (3,0°,13)
r (0,0°,1) band and R(30) line of the 13C16O16O
(3,0°,12)r(0,0°,1) band).
The peaks at 6261.83 and 6262.25 cm-1 attributed to
absorption by 13C16O16O and 12C16O16O,
respectively, were chosen to measure the relative
abundance of the two
carbon isotopes.
Analytical Chemistry, Vol. 74, No. 9, May 1, 2002 2007
23. A spectroscopic approach for making high precision CSIA measurements of the 13C/12C isotope ratio of
organic compounds, which is less expensive, does not require trained personnel, and is portable.
The technique relies on the chromatographic
separation of a mixture into individual organic
compounds, the combustion of each organic
compound into carbon dioxide, water, and
other oxidation products, and the precise
measurement of the 13C/12C isotope ratio in
the carbon dioxide gas, using the absorption
method of cavity ring-down spectroscopy.
13C/12C Isotope Ratios In Organic Compounds At Natural Abundance
24.
25. Cavity ring-down line shape profiles of the R(36)
line of 12C16O16O and the R(12) line of 13C16O16O for the
(3,00,1) – (0,00,0) combination band of carbon dioxide
near 6251 cm-1.
26. The sample cavity is surrounded by layers of thermally insulating material to provide a high degree of passive thermal stability. The cavity is further actively stabilized by means of a solid-state heating system locked to the output of a thermal sensor.
The sample pressure in the cavity is sensed using a high-linearity pressure transducer. The system computer uses this pressure data in a feedback loop to control the proportional valves which adjust the inlet and outlet gas flow of the cavity.