The Historical Development of Atomic Models
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The document traces the historical development of atomic models from ancient Greek philosophers Democritus and Leucippus proposing the first idea of atoms, to J.J. Thomson discovering the electron in 1903 and proposing atoms have a positively-charged sphere with electrons embedded, to Rutherford discovering the proton in 1911 and proving atoms have a nucleus, to Bohr solving problems with his 1913 model of electrons moving in shells around the nucleus, to Chadwick discovering the neutron in 1932 and establishing the modern nuclear model of the atom with protons and neutrons in the nucleus surrounded by electrons.
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The document provides a history of discoveries related to the atom from ancient Greek philosophers to modern quantum mechanics. It describes key contributors such as Democritus proposing atoms, Dalton establishing atomic theory, Rutherford discovering the nucleus, Bohr introducing quantum mechanics, and Heisenberg establishing the uncertainty principle. The development of atomic models progressed from simple spheres to planetary structures to quantum mechanical probability distributions.
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This document summarizes the development of atomic theory over time from ancient Greek philosophers to modern theory. It describes the key contributions of thinkers such as Democritus, Dalton, Thomson, Rutherford, Bohr, Schrodinger, and Chadwick. Their successive models proposed that atoms are small particles that join to form matter (Democritus), contain electrons and a nucleus (Thomson, Rutherford), have electrons in fixed orbits around the nucleus (Bohr), exist as electron clouds (Schrodinger), and are composed of protons, neutrons, and electrons (modern theory).
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This document outlines the development of atomic theory from ancient Greek philosophers to modern physics. It describes key contributors such as Democritus, Dalton, Thomson, Rutherford, Bohr, and Schrodinger who proposed models of the atom based on experiments. The modern atomic theory is that atoms contain a nucleus of protons and neutrons surrounded by electrons in electron clouds, and that elements are defined by their atomic number while isotopes differ in neutron number. The four fundamental forces that act on atoms are also summarized.
Physical science 4.1 : Development of Atomic Theory
Democritus was one of the first to propose the idea of atoms in 440 BCE, suggesting that matter is made up of tiny indivisible particles called atoms. In the early 1900s, experiments led scientists to develop more accurate models of the atom. Rutherford discovered the nucleus in 1909 by firing positively charged particles at a gold foil and observing some particles deflecting, indicating a small, dense nucleus. Bohr then proposed in 1913 that electrons orbit the nucleus in distinct energy levels. The modern atomic theory describes the regions where electrons are likely to be found as electron clouds.
Development of Atomic Theory
460 BC - Greek philosopher proposes the existence of the atom
He pounded materials until he made them into smaller and smaller parts
He called them atoma which is Greek for “indivisible”.
Atoms:
Matter is made up of atoms, which are the smallest particles that make up matter. Atoms contain protons, neutrons, and electrons. Protons and neutrons are located in the center of the atom, called the nucleus, while electrons orbit around the nucleus. Scientists like Democritus, Dalton, Thompson, Rutherford, and Bohr contributed theories to our modern understanding of atomic structure, such as electrons orbiting the nucleus in specific energy levels.
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The history of the atomic theories from Democritus until Bohr's atomic theories. (IB Chemistry HL - Chapter 2: Atomic Structures)
History of atoms
Greek philosopher Democritus first proposed the idea of atoms in 460 BC, reasoning that matter must be divisible into indivisible particles. However, his idea was largely ignored. In the early 1800s, John Dalton performed experiments and developed an atomic theory, stating that elements are made of identical atoms that combine to form compounds. In 1897, Joseph John Thomson discovered the electron and proposed a early atomic model where electrons were embedded in a uniform sphere of positive charge, like raisins in pudding, known as the plum pudding model.
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This document summarizes the development of atomic theory over time from ancient Greek philosophers to modern theory. It describes the key contributions of thinkers such as Democritus, Dalton, Thomson, Rutherford, Bohr, Schrodinger, and Chadwick. Their successive models proposed that atoms are small particles that join to form matter (Democritus), contain electrons and a nucleus (Thomson, Rutherford), have electrons in fixed orbits around the nucleus (Bohr), exist as electron clouds (Schrodinger), and are composed of protons, neutrons, and electrons (modern theory).
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Physical science 4.1 : Development of Atomic Theory
Democritus was one of the first to propose the idea of atoms in 440 BCE, suggesting that matter is made up of tiny indivisible particles called atoms. In the early 1900s, experiments led scientists to develop more accurate models of the atom. Rutherford discovered the nucleus in 1909 by firing positively charged particles at a gold foil and observing some particles deflecting, indicating a small, dense nucleus. Bohr then proposed in 1913 that electrons orbit the nucleus in distinct energy levels. The modern atomic theory describes the regions where electrons are likely to be found as electron clouds.
Development of Atomic Theory
460 BC - Greek philosopher proposes the existence of the atom
He pounded materials until he made them into smaller and smaller parts
He called them atoma which is Greek for “indivisible”.
Atoms:
Matter is made up of atoms, which are the smallest particles that make up matter. Atoms contain protons, neutrons, and electrons. Protons and neutrons are located in the center of the atom, called the nucleus, while electrons orbit around the nucleus. Scientists like Democritus, Dalton, Thompson, Rutherford, and Bohr contributed theories to our modern understanding of atomic structure, such as electrons orbiting the nucleus in specific energy levels.
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Greek philosopher Democritus first proposed the idea of atoms in 460 BC, reasoning that matter must be divisible into indivisible particles. However, his idea was largely ignored. In the early 1800s, John Dalton performed experiments and developed an atomic theory, stating that elements are made of identical atoms that combine to form compounds. In 1897, Joseph John Thomson discovered the electron and proposed a early atomic model where electrons were embedded in a uniform sphere of positive charge, like raisins in pudding, known as the plum pudding model.
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John Dalton performed experiments in 1800 that showed matter is made of indivisible particles called atoms. This led him to formulate Dalton's Atomic Theory which stated that atoms are identical for each element and compounds form when different types of atoms combine. While initially controversial, the theory became widely accepted after discoveries of subatomic particles like the electron and proton in the 1900s. These discoveries included J.J. Thomson finding the electron using cathode ray tubes in 1897 and identifying it as an atom's negatively charged component 2000 times smaller than hydrogen, and Rutherford proposing the nuclear model of the atom with a small, positively charged nucleus surrounded by orbiting electrons.
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John Dalton proposed the atomic theory in 1804, stating that all matter is composed of tiny, indivisible particles called atoms that cannot be divided further. Later discoveries found that atoms consist of even smaller subatomic particles, including electrons discovered by J.J. Thomson in 1897 and the nucleus discovered by Ernest Rutherford in 1910. The quantum mechanical model developed in 1926 by Schrodinger, Heisenberg and others proposed that electrons exist as waves of energy around the nucleus, rather than following fixed orbits as proposed by Niels Bohr's 1913 planetary model of the atom.
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The atomic theory has evolved over time from early Greek philosophers' idea that all matter is made of indivisible atoms, to modern scientific discoveries about atomic structure. Democritus first proposed the idea of atoms in 460 BC. In the early 1900s, Rutherford discovered the nucleus through his gold foil experiment, and Bohr proposed that electrons orbit in specific energy levels. Chadwick discovered the neutron in the 1920s, completing the standard model of the atom's subatomic particles. Today's electron cloud model depicts electrons as existing in regions rather than fixed orbits.
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Atomic models have evolved over time as scientists have learned more about the structure of atoms. Early models proposed atoms as indivisible particles (Democritus, Dalton), while later models depicted atoms as containing smaller particles like electrons (Thomson's plum pudding model). Rutherford determined atoms have a small, dense nucleus at the center with electrons in orbit around it. Bohr refined this by proposing electrons orbit in specific energy levels. Modern atomic theory is based on wave mechanics and depicts electrons as probabilistic distributions rather than definite orbits.
The discovery of nucleus
- J.J. Thomson discovered the electron through experiments showing cathode rays travel in straight lines with a negative charge.
- Rutherford's gold foil experiment showed most alpha particles passed through the foil but some bounced back, leading him to propose the nuclear model of the atom with a small, dense nucleus surrounded by electrons.
- The model was later updated with the discovery of neutrons by Rutherford and Chadwick, neutral particles that explained previously unaccounted for mass in atomic nuclei.
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1. The ancient Greek philosophers Empedocles and Democritus proposed early atomic theories, believing that all matter was made up of indivisible particles called atoms.
2. In the early 1900s, scientists such as Rutherford, Thomson, and Chadwick discovered the internal structure of atoms through experiments, finding that atoms consist of a small, dense nucleus surrounded by electrons.
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Atoms are composed of subatomic particles including electrons, protons, and neutrons. John Dalton developed atomic theory, proposing that all matter is composed of indivisible atoms that combine in simple whole number ratios. Atoms consist of a small, dense nucleus surrounded by electrons in energy levels. Rutherford's gold foil experiment revealed the small, dense nucleus at the atom's center. Niels Bohr incorporated quantum theory into atomic structure, proposing electrons orbit in discrete energy levels. The modern atomic model consists of a positively charged nucleus surrounded by electrons in quantized energy shells or orbitals.
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The document summarizes the history of atomic structure theories over thousands of years in 7 parts:
1) Ancient Greek philosophers Aristotle and Democritus proposed early atomic theories in Greece over 2000 years ago.
2) Medieval European alchemists developed early chemistry experiments between 800-900 AD trying to change materials into gold.
3) In 1808, John Dalton proposed atoms as tiny particles that could not be divided and that each element was made of its own type of atom.
4) In 1897, J.J. Thompson discovered electrons as negatively charged particles smaller than atoms.
History of atomic structure
1. J.J. Thomson discovered electrons in cathode ray tubes and concluded they were negatively charged particles smaller than atoms.
2. In the gold foil experiment, Rutherford expected alpha particles to pass through or be slightly deflected, but some were deflected at large angles or rebounded, indicating the positive charge was concentrated in a small nucleus.
3. This led Rutherford to propose the nuclear model of the atom with electrons orbiting a small, dense positively charged nucleus.
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Atomic theory describes matter as composed of atoms, the basic units that constitute chemical elements. Democritus first proposed the idea of indivisible atoms in ancient Greece. In the early 1900s, J.J. Thomson discovered the electron and proposed a "plum pudding" model of the atom. Ernest Rutherford discovered the nucleus through alpha particle scattering experiments, leading to the planetary model of electrons orbiting the nucleus. Niels Bohr later adjusted this model to account for electron stability.
Atom models
1) Early models proposed atoms as indivisible particles (Democritus). Dalton later showed atoms of different elements have different properties.
2) Thomson's "plum pudding" model showed atoms contain smaller, negatively charged particles (electrons) scattered in a positive sphere.
3) Rutherford's gold foil experiment revealed atoms have small, dense nuclei containing mass, with electrons orbiting at distances.
4) Bohr's model placed electrons in specific energy levels around the nucleus, like planets orbiting the sun. Modern models use wave mechanics.
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The atomic theory has evolved over time from early Greek philosophers' idea that all matter is made of indivisible atoms, to modern scientific discoveries about atomic structure. Democritus first proposed the idea of atoms in 460 BC. In the early 1900s, Rutherford discovered the nucleus through his gold foil experiment, and Bohr proposed that electrons orbit in specific energy levels. Chadwick discovered the neutron in the 1920s, completing the standard model of the atom's subatomic particles. Today's electron cloud model depicts electrons as existing in regions rather than fixed orbits.
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The discovery of nucleus
- J.J. Thomson discovered the electron through experiments showing cathode rays travel in straight lines with a negative charge.
- Rutherford's gold foil experiment showed most alpha particles passed through the foil but some bounced back, leading him to propose the nuclear model of the atom with a small, dense nucleus surrounded by electrons.
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The document discusses the history of ideas about the composition of matter from ancient Greek philosophers to early alchemists. It describes how Thales of Miletus first proposed matter was composed of water, while Empedocles suggested four elements of air, water, earth, and fire. Leucippus and Democritus introduced the first atomic theory that matter could be divided into indivisible fragments called atoms. Aristotle rejected atomism, believing matter was composed of earth, water, air, and fire with properties of hot, cold, dry, and wet. Alchemy emerged believing matter could be transformed, leading to early chemistry.
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This document discusses the development of atomic theory from ancient Greece to modern times. It begins with Democritus' idea in 400 BC that matter is made of indivisible atoms. John Dalton expanded on this in 1803 with his Billiard Ball Model, proposing atoms as tiny invisible particles that make up elements. Ernest Rutherford discovered the nucleus in 1911 and protons in 1920 with his Planetary Model. Niels Bohr proposed fixed electron energy levels around the nucleus in 1913. Modern atomic theory incorporates Erwin Schrodinger's 1926 Electron Cloud Model and James Chadwick's 1932 discovery of neutrons in the nucleus.
1a. History Of The Atom (2)
1. The ancient Greek philosophers Empedocles and Democritus proposed early atomic theories, believing that all matter was made up of indivisible particles called atoms.
2. In the early 1900s, scientists such as Rutherford, Thomson, and Chadwick discovered the internal structure of atoms through experiments, finding that atoms consist of a small, dense nucleus surrounded by electrons.
3. Niels Bohr contributed to the modern atomic model in 1913 by proposing that electrons orbit the nucleus in fixed shells or energy levels.
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This document provides a timeline of the development of atomic models from ancient Greek philosophers to present day. It describes early theories from Democritus and Aristotle that matter is made of indivisible particles. John Dalton later proposed atoms as indestructible, indivisible spheres that combine in simple ratios. J.J. Thomson's discovery of electrons led to the "plum pudding" model. Ernest Rutherford's gold foil experiment showed atoms are mostly empty space with a small, dense positively charged nucleus. Niels Bohr incorporated electrons orbiting the nucleus. James Chadwick's discovery of neutrons completed atomic structure.
Isotopes
This document discusses isotopes and atomic structure. It defines isotopes as atoms of the same element that have the same number of protons but different numbers of neutrons. Isotopes have the same chemical properties but slightly different physical properties. The document also discusses nucleon number, which is the total number of protons and neutrons in an atom's nucleus. The mass number equals the nucleon number. Radioactive isotopes are unstable and undergo nuclear decay over time into stable daughter isotopes.
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Atoms are composed of subatomic particles including electrons, protons, and neutrons. John Dalton developed atomic theory, proposing that all matter is composed of indivisible atoms that combine in simple whole number ratios. Atoms consist of a small, dense nucleus surrounded by electrons in energy levels. Rutherford's gold foil experiment revealed the small, dense nucleus at the atom's center. Niels Bohr incorporated quantum theory into atomic structure, proposing electrons orbit in discrete energy levels. The modern atomic model consists of a positively charged nucleus surrounded by electrons in quantized energy shells or orbitals.
History Of Atomic Structure
The document summarizes the history of atomic structure theories over thousands of years in 7 parts:
1) Ancient Greek philosophers Aristotle and Democritus proposed early atomic theories in Greece over 2000 years ago.
2) Medieval European alchemists developed early chemistry experiments between 800-900 AD trying to change materials into gold.
3) In 1808, John Dalton proposed atoms as tiny particles that could not be divided and that each element was made of its own type of atom.
4) In 1897, J.J. Thompson discovered electrons as negatively charged particles smaller than atoms.
History of atomic structure
1. J.J. Thomson discovered electrons in cathode ray tubes and concluded they were negatively charged particles smaller than atoms.
2. In the gold foil experiment, Rutherford expected alpha particles to pass through or be slightly deflected, but some were deflected at large angles or rebounded, indicating the positive charge was concentrated in a small nucleus.
3. This led Rutherford to propose the nuclear model of the atom with electrons orbiting a small, dense positively charged nucleus.
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1. The document discusses the early theories of the structure of atoms from ancient Greek philosophers to the modern atomic model.
2. It describes the discoveries of subatomic particles like the electron by J.J. Thomson and the nucleus by Ernest Rutherford through experiments.
3. Later scientists like Niels Bohr, James Chadwick, and Erwin Schrodinger further refined the model, with Bohr proposing electron shells and orbits, Chadwick discovering the neutron, and Schrodinger explaining electron probability clouds.
Aneesh bapat structure of an atom
An entry in the 'schools for you' project. By Aneesh Bapat, class 8 from Abhinav Vidyalaya English Medium High School, Pune, India.About the various theories by different scientists about the structure of the atom.
atomos.ppt
The document summarizes the development of atomic theory over time. It describes early atomic models proposed by Democritus, Dalton, Thomson, and Rutherford. Democritus proposed that matter is made of indivisible particles called atoms. Dalton established atoms as fundamental units of matter. Thomson's plum pudding model depicted atoms as positively charged spheres with electrons scattered within. Rutherford's gold foil experiment showed atoms have small, dense nuclei. The Bohr model depicted electrons orbiting the nucleus in distinct energy levels. Later, the quantum mechanical model depicted electrons as existing as clouds within an atom.
atomos POWERT POINT PRESENTATION FOR GRADE 8.ppt
The document summarizes the development of atomic theory over time from Democritus' idea of indivisible atoms in 400 BC to the current wave model. It describes key models including Thomson's plum pudding model, Rutherford's discovery of the nucleus from his gold foil experiment, Bohr's model of electrons in distinct orbits around the nucleus, and the modern wave model where electrons are described as existing in electron clouds or energy levels rather than distinct orbits.
atomos presentation. grade 11 lesson.ppt
The document summarizes the development of atomic theory over time from Democritus' idea of indivisible atoms in 400 BC to the current wave model. It describes key models including Thomson's plum pudding model, Rutherford's discovery of the nucleus from his gold foil experiment, Bohr's model of electrons in distinct orbits around the nucleus, and the modern wave model where electrons exist as probabilities in electron clouds. The location of electrons depends on their energy level rather than fixed orbits.
Dear Democritus...
1) The document traces the history of atomic theory from ancient Greece to modern times, starting with Democritus' idea of atoms that was rejected by Aristotle.
2) In the 1600s, chemistry emerged as a science, with Antoine Lavoisier distinguishing elements and compounds. John Dalton further developed atomic theory in 1803, proposing atoms of different elements have different properties.
3) Ernest Rutherford's 1909 gold foil experiment discovered the atomic nucleus, replacing the plum pudding model and showing atoms have mostly empty space. This led to models placing electrons in distinct orbits around the nucleus.
Similar to The Historical Development of Atomic Models (20)
LESSON 2 THE DEVELOPMENT OF THE ATOMIC THEORY.pptx
LESSON 2 THE DEVELOPMENT OF THE ATOMIC THEORY.pptx
Lesson 4 Not Indivisible (The Structure of the Atom)
Lesson 4 Not Indivisible (The Structure of the Atom)
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The document discusses the three states of matter - solids, liquids, and gases. Solids have a definite shape and size, liquids take the shape of their container but have a definite volume, and gases fill their container and have no definite shape or volume. It compares the properties of each state, including how they are affected by pressure, with solids maintaining their shape against pressure while liquids and gases can be compressed.
Bacteria and enzymes in digestion
Bacteria in the large intestine produce vitamins that are absorbed by the body. Probiotic foods contain beneficial bacteria. Digestive juices contain enzymes that break down nutrients into smaller molecules. There are three main types of enzymes - carbohydrase breaks down carbohydrates, protease breaks down proteins, and lipase breaks down lipids with help from bile. Drugs affect body chemistry and there are medicinal and recreational drugs. Recreational drugs have no health benefits and can be addictive.
Past simple
The past simple tense is used to describe actions that were completed in the past. For regular verbs, the past simple form is created by adding "-ed" to the base form of the verb. Irregular verbs have varying past simple forms that must be memorized. Examples of common regular verbs like "talked" and irregular verbs like "ate" are provided. A practice exercise asks the reader to fill in the blanks with the correct past simple form of verbs like "tidy" and "phone."
Physical and Chemical Change in Matter
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Systems of animals and human
This document provides an overview of several human body systems and their functions, including the digestive, reproductive, circulatory, respiratory, excretory, nervous, skeletal, muscular, and immune systems. It describes how the digestive system breaks down food, the reproductive system produces and stores gametes, the circulatory system transports substances around the body, the respiratory system supplies oxygen and removes waste, and the excretory system removes waste. It also explains that the nervous system processes information, the skeletal and muscular systems provide support and movement, and the immune system protects the body from pathogens.
Science - Weather/Wind/Stars
This presentation is a combination of different topics for review.
*The numbers are hyperlinked to the corresponding question.
Science Trivia
This document contains a series of questions about science topics such as the composition of the Earth, characteristics of plants and animals, and basic physical phenomena. It tests knowledge on subjects like biology, chemistry, physics and geography through 20 multiple choice or fill-in-the-blank questions about things like the parts of plants and animals, the states of matter, and properties of electricity and weather.
Wind
Wind is produced by air flowing from areas of higher atmospheric pressure to areas of lower pressure. During the day, land heats up faster than the sea, causing warm air over land to rise and be replaced by cooler air from the sea in a sea breeze. At night, land cools faster, and cooler air flows from land to sea in a land breeze. Wind has several uses, including powering sailing boats, drying clothes and grains, and turning windmills to generate electricity.
Weather and Stars
The document discusses the water cycle and different types of clouds and precipitation. It explains the water cycle as evaporation of water from oceans and rivers into water vapor, transpiration of water vapor from plants, condensation of water vapor back into liquid form, and precipitation of water falling back to earth. It then defines dew, fog, and the three main types of clouds - cirrus, stratus, and cumulus. Finally, it defines precipitation as moisture falling from the air to the ground and provides examples of rain, snow, and hail.
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Types of clouds
The document describes 6 types of clouds: cirrostratus, cirrocumulus, altostratus, altocumulus, nimbostratus, and stratocumulus. Cirrostratus are high, thin, whitish veil clouds. Altostratus are mid-level gray or blue cloud sheets that partially obscure the sun. Nimbostratus are dark, continuous rain clouds thick enough to block out the sun.
Antibodies
Basic Immunology lesson for middle school. I included the blood components to give them a brief background.
*You are free to edit if you find this useful to your class.
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This document provides examples of words containing the short "i" vowel sound and long "i" vowel sound. For the short "i" sound, examples include lip, pin, lick, pink, pig, six, slip, and spill. For the long "i" sound, examples include fire, kite, bite, pine, drive, lime, pipe, cry, and shy. The document is intended to teach the difference between these two vowel sounds through examples.
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Materials p5
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Dominant and recessive
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Chromosomal abnormalities
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Heredity and Diversity of Living Things
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Animal life cycle
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This document discusses animal reproduction. It describes the male and female reproductive systems of cows, including testes, ovaries, sperm and eggs. It explains the processes of internal and external fertilization, where fertilization occurs inside or outside the body. It provides examples of animals that exhibit each type of fertilization. The document also briefly discusses asexual reproduction through budding in hydra and flatworms. It notes selective breeding and artificial breeding as methods used by humans to influence animal offspring traits.
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The cost of acquiring information by natural selection
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Alternate Wetting and Drying - Climate Smart Agriculture
Alternate Wetting and Drying - Climate Smart AgricultureInternational Food Policy Research Institute- South Asia Office
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Physiology of Male reproduction.
Video mentioned at page no. 23 as summary for better understanding
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Neutralizing antibodies, pivotal in immune defense, specifically bind and inhibit viral pathogens, thereby playing a crucial role in protecting against and mitigating infectious diseases. In this slide, we will introduce what antibodies and neutralizing antibodies are, the production and regulation of neutralizing antibodies, their mechanisms of action, classification and applications, as well as the challenges they face.
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Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Current descriptions of immersive learning cases are often difficult or impossible to compare. This is due to a myriad of different options on what details to include, which aspects are relevant, and on the descriptive approaches employed. Also, these aspects often combine very specific details with more general guidelines or indicate intents and rationales without clarifying their implementation. In this paper we provide a method to describe immersive learning cases that is structured to enable comparisons, yet flexible enough to allow researchers and practitioners to decide which aspects to include. This method leverages a taxonomy that classifies educational aspects at three levels (uses, practices, and strategies) and then utilizes two frameworks, the Immersive Learning Brain and the Immersion Cube, to enable a structured description and interpretation of immersive learning cases. The method is then demonstrated on a published immersive learning case on training for wind turbine maintenance using virtual reality. Applying the method results in a structured artifact, the Immersive Learning Case Sheet, that tags the case with its proximal uses, practices, and strategies, and refines the free text case description to ensure that matching details are included. This contribution is thus a case description method in support of future comparative research of immersive learning cases. We then discuss how the resulting description and interpretation can be leveraged to change immersion learning cases, by enriching them (considering low-effort changes or additions) or innovating (exploring more challenging avenues of transformation). The method holds significant promise to support better-grounded research in immersive learning.
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Description:
Dive into the fascinating realm of solid-state physics with our meticulously crafted online PowerPoint presentation. This immersive educational resource offers a comprehensive exploration of the fundamental concepts, theories, and applications within the realm of solid-state physics.
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Band Theory: Explore the electronic band structure of solids and understand how it influences their conductive properties.
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Magnetic Properties: Investigate the magnetic behavior of solids, including ferromagnetism, antiferromagnetism, and ferrimagnetism.
Optical Properties: Examine the interaction of light with solids, including absorption, reflection, and transmission phenomena.
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快速办理(UAM毕业证书)马德里自治大学毕业证学位证一模一样
学校原件一模一样【微信：741003700 】《(UAM毕业证书)马德里自治大学毕业证学位证》【微信：741003700 】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原。
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
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6:个人职称评审加20分
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Pests of Storage_Identification_Dr.UPR.pdf
InIndia-post-harvestlosses-unscientificstorage,insects,rodents,micro-organismsetc.,accountforabout10percentoftotalfoodgrains
Graininfestation
Directdamage
Indirectly
•theexuviae,skin,deadinsects
•theirexcretawhichmakefoodunfitforhumanconsumption
About600speciesofinsectshavebeenassociatedwithstoredgrainproducts
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Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
�
cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
�
) with
Λ
CDM. Therefore unlike low-
�
Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
HUMAN EYE By-R.M Class 10 phy best digital notes.pdf
Class 10 human eye notes physics
Handwritten best quality
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
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The cost of acquiring information by natural selection
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Microbiology of Central Nervous System INFECTIONS.pdf
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Mechanisms and Applications of Antiviral Neutralizing Antibodies - Creative B...
Immersive Learning That Works: Research Grounding and Paths Forward
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Introduction_Ch_01_Biotech Biotechnology course .pptx
Introduction_Ch_01_Biotech Biotechnology course .pptx
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Describing and Interpreting an Immersive Learning Case with the Immersion Cub...
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...
HUMAN EYE By-R.M Class 10 phy best digital notes.pdf
HUMAN EYE By-R.M Class 10 phy best digital notes.pdf
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
The Historical Development of Atomic Models
- 1. The Historical Development of Atomic Models
- 2. Vocabulary • Proton • Neutron • Electron • Atom • Nucleus
- 3. The first idea of atoms came from two Greek philosophers, Democritus and Leucippus in the 5th century BC. The word atom comes from the Greek word “atomos” which means not “cut-able” or divisible. Democritus Leucippus
- 4. J. Dalton Dalton viewed the atom as a small solid ball that cannot be broken. However, in the late 19th century, scientists began to obtain experimental evidences which showed that atoms are not like solid balls, and they could be broken.
- 6. J. J. Thomson • English physicist • Discovered the electron, a negatively-charged particle. • In 1903 Thomson proposed a new model of atom. The atom was described as positively-charged sphere embedded with electrons
- 8. E. Rutherford • In 1911, he discovered the proton, a positively- charged particle. • He proved that atom has nucleus. • He described the new model as tiny, dense, positively-charged electrons.
- 10. N. Bohr In 1913, Bohr solved this problem by proposing that the electrons could move in shells around the nucleus with particular energies.
- 12. J. Chadwick • In 1932, James Chadwick proved the existence of neutrons, the neutral particles in the nucleus. • He discovered that nucleus is surrounded by electrons. • Neutrons contribute approximately of the half of the mass of an atom.
- 14. This model is known as the nuclear atom and includes the three subatomic particles. • The atom has a nucleus at its center. The nucleus has protons and neutrons. The nucleus has positive charges because of the protons. • A “cloud” of electrons surrounds the nucleus. The electrons move at nearly the speed of light. • Most of the atom is empty.