Different Types of Radioactive Counters or detectors used in analyzing low or high penetrating power radiation or particles are explained briefly with their advantages and disadvantages.
Medha Thakur (M.Sc Chemistry)
Geiger–Müller Counter is a hand-held radiation survey instrument used in Radiation Dosimetry,Nuclear Physics,Experimental Physics & Radiological Protection.
gm counter .working principle of gm counter, construction, advantage and disadvantage of gm counter.
Scintillation counter, its history, solid and liquid scintillation, scintillation cocktail, photomultiplier tube, advantage, and disadvantage.
Geiger–Müller Counter is a hand-held radiation survey instrument used in Radiation Dosimetry,Nuclear Physics,Experimental Physics & Radiological Protection.
gm counter .working principle of gm counter, construction, advantage and disadvantage of gm counter.
Scintillation counter, its history, solid and liquid scintillation, scintillation cocktail, photomultiplier tube, advantage, and disadvantage.
Complete detail about the Radiopharmaceutical, General Introduction, Radioactive substance, Radioactive rays like alpha, beta and gamma rays. All the Measurement method to determine the radioactivity of any element and widely used instrument Geiger Muller Counter. And some Radiopharmaceutical product used in many diagnosis , treatment such like sodium iodide solution & capsule, Rose Bengal I 131 and Application of Radiopharmaceuticals.
Pharmaceutical Inorganic chemistry UNIT-V Radiopharmaceutical.pptx
Isotopes Types of decay
Alpha rays, which could barely penetrate a piece of paper
Beta rays, which could penetrate 3 mm of aluminium
Gamma rays, which could penetrate several centimetres of lead
Units of Radioactivity:
Measurement of Radioactivity
The measurement of nuclear radiation and detection is an important aspect in the identification of type of radiations (, , ) and to assay the radionuclide emitting the radiation, suitable detectors are required. The radiations are identified on the basis of their properties.
e.g. Ionization effect is measured in Ionization Chamber, Proportional Counter and Geiger Muller Counter.
The scintillation effect of radiation is measured using scintillation detector and the photographic effect is measured by Autoradiography.
Gas Filled Detectors:
Ionization Chamber:
Proportional Counters:
Geiger-Muller Counter
Properties of α, β, γ radiations
Half –life of Radioelement
Sodium Iodide (I131)
Handling and Storage of Radioactive Material:
Storage of Radioactive Substances –
Precautions For Handling Radioactive Substances
Labelling of Radioactive Substances
Pharmaceutical Application Of Radioactive Substances
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
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.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
ISI 2024: Application Form (Extended), Exam Date (Out), EligibilitySciAstra
The Indian Statistical Institute (ISI) has extended its application deadline for 2024 admissions to April 2. Known for its excellence in statistics and related fields, ISI offers a range of programs from Bachelor's to Junior Research Fellowships. The admission test is scheduled for May 12, 2024. Eligibility varies by program, generally requiring a background in Mathematics and English for undergraduate courses and specific degrees for postgraduate and research positions. Application fees are ₹1500 for male general category applicants and ₹1000 for females. Applications are open to Indian and OCI candidates.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
2. Contents Introduction
Classification Of Detectors
Gas Ionisation System (GI)
Types of (GI) counters
(a) Gas Flow Proportional Counters
b) Geiger – Muller Counters
Types of Geiger Counters
Solid Scintillators (SS)
Liquid Scintillators (LS)
Solid State (Semi-Conductor) Counters
3. Introduction
• various radiation have different
penetrating power & particles are
least penetrative.
• β particles are 10 times as penetrative
as α and γ rays are very penetrative.
• Beacuse of the wide variation in
penetrating power of the various
radiation, detectors employed for
counting the radiation will depend on
the type and energy of the radiation
emitted.
Radiation
Low
Pose a major
Problem for
detection
Medium
Detected by using
low density
materials (Gases)
Very High
Detected by using
denser material
(Solids)
With Penetrating
Power
5. Gas Ionisation System (GI)
• Principle:
• When radiation passes through a gas, energy is
passed on to some of the gas molecules. These gas
molecules may ionise to a positive ion.
• e.g. If a suitable electric field is applied, the ions
can be collected and the magnitude of the resulting
currents can be realated to the amount of the
radiation initially responsible for the ionsation.
• The applied strength not only enables collection of
electrones or ions but also allows multiplication.
6. Types of (GI) counters
GI COUNTERS
(a) GAS FLOW
PROPORTIONAL COUNTERS
(b) GEIGER –
MULLER COUNTERS
7. (a) GAS FLOW PROPORTIONAL
COUNTERS
• In this type of detectors the applied field is such that the number of
ion pairs collected is proportional to the energy of the incident
radiation.
• This is achieved by placing the source, inside the counter and by
carefully controlling such experimental parameters as the geometry
of the counter, the flow rate of the gas, and the applied voltage.
• The output pulse is proportional to the energy of incident radiation.
Therefore by using a pulse- height analyser, it is possible to
differentiate between different isotopes.
9. GAS FLOW PROPORTIONAL COUNTERS
Disadvantages:-
• 1. A very stable high
voltage supply is
needed.
• 2. A very stable, high
gain amplifier is
needed.
• 3. The gas is used for
the counter is very
expensive.
Advantages:-
•1. gives a high and
reproducible detection
efficiency.
•2. used to investigate low
levels of radio-isotopes in
environmental sample.
•3. The sample to be counted
is normally placed inside
the counter, so that the
absorption problems of α
emitters are minimised.
10. (b) GEIGER – MULLER COUNTERS
Principle:
• In this type of detector, the applied field is increased to such
an extent that the ionisation induced by the acceleration of
initially produced ions and electrons results in virtually all of
the gas in the viscinity of the anode being ionised This is
known as ‘ avalanche effect’.
GEIGER – MULLER COUNTERS
Advantage:
They are simple and
effective.
Disadvantage:
To be compared with a standard.
They work only at high voltages (1000-
1500 V).
11. Types of Geiger
Counters
GEIGER
COUNTERS
1) END-WINDOW
used for counting solid samples.
It is cylindrical with a thin mica land
window. cylindrical case cathode and
central metal wire anode.
sample is placed directly under the End-
window. absorption of the radiation by the
window, and scattering of the radiation.
2) GEIGER COUNTER for LIQUID
SAMPLES
used for counting liquid samples
made of glass and consist of a central
gas filled tube containing the electrodes
surrounded by cylindrical ‘sheath’ into
which the liquid to be counted is placed.
13. Solid Scintillators (SS)
Principle:
• The most significant penetration into solid materials
is achieved by γ rays.
• They cause very little ionisation in gases and hence
are poorly teasured by gas ionsiation methods.
• rays are most efficiently counted using a solid
absorber. which acts as a scintillator.
• This is usually called a ‘Crystal or phosphor’. The
most popular crystal is N2- iodide containing traces of
thallium (t) iodide. The symbol used is Na2|Th|.
14. CONSTRUCTION
• crystals are cylindrical and a light-tight
aluminium can.
• One end is kept in contact with the PM
tube at which the photocathode is located.
• reflection losses minimised by a films of
transparent silicon oil.
• Counters Used:
• Plastic scintillators are used for β
counting.
• Some specialised counters use NaI(TL) for
Low energy γ and X-ray counting.
The main Criteria for a scintillators:
• 1. Good absorption of incident radiation (i.e.
high density).
• 2. High efficiency of photon production.
• 3. Little/ no reabsorption of the photons by
crystal.
• 4. Emitted photons just have a wavelength
compatible with the PM tube (320-720 nm for
glass window).
• anthracene and stilbene meet these criteria.
16. Liquid Scintillators (LS)
Principle:
• GI counters and SS counters enable us to count isotopes which
emmit gamma rays and or medium to high energy β particles.
• But, there are several low energy β emitters for which these
technologies are inappropriate because of low penetration of the
β- particles,
• it is essential that the, isotope to be counted should be internally
mixed with the scintillator and not external to it as for solid
scintillators.
• This is done by dissolving sample wholly or partly in a solvent
containing the scintillator.
17. Construction and Working
1) Solvents :- Incident radiation should readily for electronically excited
solvent molecules. These readily transfer their energy to the scintillator.
Solvents are usually aromatic hydrocarbons such as xylene, toluene,
dioxane, etc.
2) Scintillator (primary soulte) :- accepts energy from solvent and is
raised to excited state and then de-excited by emitting light photon ( λ
range 300-400 nm) which is counted by PM tube. e.g. Large organic
molecules.
3) Secondary Solute :- Whenever maximum efficiency is required a
secondary solute is used.
They emit light photons of λ range 400-500 nm, where the PM tube is
more sensitive. The excitation energy of the 1° solute molecule is
transferred to the larger 2° solute molecules.
18. Scintillation
Counters
Advantages
simple to operate.
sensitivity to all types of
ionising radiations.
Distinguishes between photons of
different energies.
Short resolving time & more
efficient, fast and accurate
counting (especially γ rays).
Dis
advantages
A massive PM tube is necessary.
At low energies, the counter
response is not 100 % .
19. Solid State (Semi-Conductor) Counters
Principle:
• They are exemplified by the Ge (Li) system.
• Detectors of this type consist of an n-type
semiconductor and p-type semiconductor; separated by
an ultra-pure radiation sensitive region.
• The n-type semiconductor contains negative sites (e-s)
for conduction. The P-type S.C. has a deficiency of e-s or
‘Positive hole’.
• The SS ionisation detector requires an element whose
atoms are not only small enough to fit into the
interstitial sites of Ge; but also readily ionise e.g. Li.
20. Construction and Working
• In Ge (Li) detector, the Li atoms are allowed to migrate or ‘drift’ to
some of the p-sites in a cylinder of p-n Ge.
• Each p-site is deficient in 1e- and each Li is readily ionised and gives
up an e-.
• Hence a p-type S.C. and an n-type S.C. are separated by an ultra-pure
and electrically neutral region (intrinsic region).
• If radiation enters the neutral region (intrinsic), it will cause
ionisation.
• By applying a suitable potential, the e-s can be collected and amplified
to a measurable pulse.
21. Advantages 1. used for γ ray counting.
2. excellent resolution – 100 times better than NaI (TL)
complexes.
3. Pulse height is directly proportional to the energy of the
incident (gamma) radiation.
Dis-
advantages
1. Li atoms are very mobile therefore the Ge(Li) detector has to
be maintained at low temp
2. poorer detection efficiency because of smaller size [as
compared to NaI (TL)]
3. not as effective as NaI (TL) crystals for the samples with
high countrate.
4. must be kept in vacuum.