Superconductors are materials that exhibit zero electrical resistance below a critical temperature. The first superconductor, mercury, was discovered in 1911 by Kamerlingh Onnes. When cooled below 4.2K, mercury's resistance vanished. Other key properties include: magnetic fields destroy superconductivity above a critical value; a phase transition occurs between normal and superconducting states below the critical temperature; and the Meissner effect causes magnetic fields to be expelled. Important factors controlling superconductivity are critical temperature, critical magnetic field, and critical current density. Applications include maglev trains which levitate and propel using principles of magnetic levitation and superconducting electromagnets. Current maglev systems operate at speeds up to
Properties of superconductors, Effects of the magnetic field, variation of resistance with temperature, Meissner Effect, isotope effect, Energy Gap, Coherence Length, BCS Theory, Types of superconductors ,
Properties of superconductors, Effects of the magnetic field, variation of resistance with temperature, Meissner Effect, isotope effect, Energy Gap, Coherence Length, BCS Theory, Types of superconductors ,
Basically i have tried giving every details about the phenomenon Superconductivity in the simplest way. This is my first upload.I'll be very glad if u all give your valuable feedback. Thank u.
Basic Information regarding superconductors.
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.
This power-point presentation include
1. Introduction to Superconductors
2. Discovery
3. Properties
4. Important factors
5. Types
6. High Tc Superconductors
7. Magnetic Levitation and its application
8. Josephson effect
9. Application of superconductors
#Tip- You can further add videos which are available in vast amount on YouTube regarding superconductivity(specially magnetic levitation)
P.S.Does not contain information about Cooper pairs and BCS theory
Superconductivity is the ability of certain materials to conduct electric current with practically zero resistance. This capacity produces interesting and potentially useful effects. For a material to behave as a superconductor, low temperatures are required.
Basically i have tried giving every details about the phenomenon Superconductivity in the simplest way. This is my first upload.I'll be very glad if u all give your valuable feedback. Thank u.
Basic Information regarding superconductors.
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.
This power-point presentation include
1. Introduction to Superconductors
2. Discovery
3. Properties
4. Important factors
5. Types
6. High Tc Superconductors
7. Magnetic Levitation and its application
8. Josephson effect
9. Application of superconductors
#Tip- You can further add videos which are available in vast amount on YouTube regarding superconductivity(specially magnetic levitation)
P.S.Does not contain information about Cooper pairs and BCS theory
Superconductivity is the ability of certain materials to conduct electric current with practically zero resistance. This capacity produces interesting and potentially useful effects. For a material to behave as a superconductor, low temperatures are required.
There are 22 slides.Contents are
(1)What is Maglev?
(2)Magnetic Levigation.
(3)Basic Principle of Maglev Trains.
(4)Types of Maglev Trains.
(5)EMS(Electromagnetic Suspension).
(6)ESD(Electrodynamic Suspension).
(7)Inductrack.
(8)Conclusion.
ELECTROMAGNETISM
INTRODUCTION
The phenomenon where by electricity creates magnetism is known as electromagnetism. When an insulated wire is wrapped with round an iron nail and the ends of the wire connected to the battery the nail becomes capable of picking up iron fillings paper. This is a simple electromagnet. The nail has been magnetized by the current in the wire. Disconnecting the wire from the battery the paper clips fall off. The nail looses most of first magnetism when the current is switched off. The passage of electric current along a wire creates a magnetic field around the wire. The lines of forces due to a straight current carrying wire are circles, center on the wire on the wire. The field is strongest near the wire the direction of the magnetic field is r
Very important Chapter of physics because it contains all the important laws needed to understand concepts in physics.
And i hope it will be helpful to you
Magnetic Effects of Electric Current for Grade 10th StudentsMurari Parashar
In this chapter, we will study the effects of electric current : Moving charges or electric current generates a magnetic field. This is useful to CBSE Students.
Electric charges
Current
Potentialand its difference
Circuits
Heating effects
Magnetic effects
Magnetic Field Lines in straight and coiled conductors
Electromagnets
Electromagnetic Induction
Motors and Generators
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/
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.
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.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Nucleophilic Addition of carbonyl compounds.pptxSSR02
Nucleophilic addition is the most important reaction of carbonyls. Not just aldehydes and ketones, but also carboxylic acid derivatives in general.
Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
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).
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.
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.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
Superconductors
1.
2. What are superconductors?
Some materials offer zero resistance to the flow of current below a specific
temperature. They are called superconductors.
Mostly they are metals, alloys and ceramics.
This specific temperature is called the critical temperature or the
transition temperature(at which the transition from normal to
superconducting state of the material takes place).
This phenomenon is termed as superconductivity.
3. Discovery
Super conductivity was first discovered in 1911 by the Dutch physicist, Heike
Kammerlingh Onnes.
Onnes felt that a wire’s resistance would vanish if it is cooled too much. This
suggested that there would be a steady decrease in electrical resistance,
allowing for better conduction of electricity.
Onnes passed a current through a pure mercury wire and measured its
resistance as he gradually decreased its temperature. To his surprise there
was little or no resistance at 4.2 K.
4. At 4.2 K the electrical resistance of mercury vanished, meaning
extremely good conduction of electricity that is now known as
Super conductivity.
5.
6. General Properties of Super Conductors.
Virtually Zero electrical resistance
Effect of impurities: Critical temperature is lowered by the addition
of impurities.
Magnetic field effect: Application of strong magnetic field beyond
critical value destroys the superconductivity resulting in the
transition to the normal state again.
Phase transition: phase transition from normal to superconducting
state occurs when it is cooled below the critical temperature Tc
9. Reason for Meissner Effect:
It has been explained by the London equation which depicts that the magnetic
field inside the superconductor decreases exponentially than that around its
surface.
The applied magnetic field is expelled from the inside of the superconductor and
bent around it. These magnetic fields are expelled because under the influence
of a magnetic field, surface currents develop to create magnetization within the
superconductor. This magnetization is equal and opposite to the magnetic field,
resulting in cancelling out the magnetic field everywhere within the
superconductor. Superconductors are strongly diamagnetic. Since diamagnetics
have a magnetization that opposes any applied magnetic field, the
superconductor is repelled by the magnetic field. When a magnet is placed
above a superconductor, this repelling force can be stronger than gravity,
allowing the magnet to levitate above the superconductor.
10. Important Factors controlling
superconductivity
1. Critical Temperature: The temperature below which resistance of a
superconductor becomes zero.
2. Critical Magnetic Field: Minimum magnetic field required to destroy
the superconducting state
3. Critical Current density: The minimum amount of current that can
pass through a superconductor without transitioning it back to the
normal state.
11. Magnetic Levitation
Magnetic levitation is a method by which an object is suspended with no
support other than the magnetic fields. Magnetic force is used to
counteract the effects of the gravitational field and any other
accelerations.
The two main points in magnetic levitation are lifting force: so that the
object lifts upwards against gravity and stability: so that the object does
not flip or fly off
Magnetic levitation is the result of Meissner effect.
15. Maglev trains
Maglev is short for magnetic levitation.
Maglev trains float over a guide way using the basic principles of magnets
to replace the old steel wheel and track trains.
There is no physical contact between the train and the track, so the only
resistance offered to them is by air. Friction is greatly reduced and so these
trains can travel at very high speeds.
Currently, Japan and South Korea have operational maglev systems.
Their speed can be as much as 500 km/h
They work on the principle of EDS and EMS.
16. Working:
Electrodynamic Suspension(EDS)
This is the technique used by the Japanese system of maglev train.
The train has superconductor electromagnets fitted in its base. The track
has electromagnetic coils. The sideways have electromagnets plus
propulsion and guidance coils.
The reason for the levitation is the Meissner effect.
17. To propel the vehicle, the electromagnets are placed on the sides of the
guide-way. They are energized according to the time when the train
reaches that particular spot and are de-energized the rest of the time.
The train is pushed due to repulsion of like poles and is pulled due to
attraction of unlike poles. So the train moves forward. Now the next set of
pole comes into action and thereby a continuous motion is produced. The
polarity of the electromagnets is constantly changing because of an
alternating current. So the train moves in only one direction.
18. Superconducting electromagnets are used as the coils of these
electromagnets can carry huge amount of current as the resistivity is
almost zero. Hence, the magnetic force is higher and hence higher speed
is achieved.
Propulsion coils also provide guidance. The emf induced in coils on both
sides of the train(along the sideways) are equal in magnitude but opposite
in direction which cancel out each other. Hence, the train keeps moving in
the centre.
19.
20. Disadvantage of EDS
At lower speeds (at the start of motion), levitation cannot be achieved and
therefore, wheels also have to be provided. When the speed is sufficient
enough to induce enough emf and produce magnetic field, then the train
levitates and wheels are not required then.