Diffusion

Top: A single molecule moves around randomly. Middle: With more molecules, there is a clear trend where the solute fills the container more and more uniformly. Bottom: With an enormous number of solute molecules, randomness becomes undetectable: The solute appears to move smoothly and systematically from high-concentration areas to low-concentration areas. This smooth flow is described by Fick's laws. A diffusion process that obeys Fick's laws is called normal or Fickian diffusion; otherwise, it is called Contents • 1 History • 2 Fick's first law • 2.1 Variations of the first law • 2.2 Derivation of Fick's first law for gases • 3 Fick's second law • 3.1 Derivation of Fick's second law • 4 Example solutions and generalization • 4.1 Example solution 1: constant concentration source and diffusion length • 4.2 Example solution 2: Brownian particle and Mean squared displacement • 4.3 Generalizations • 5 Applications • 5.1 Fick's flow in liquids • 5.2 Sorption rate and collision frequency of diluted solute • 5.3 Biological perspective • 5.4 Semiconductor fabrication applications • 5.4.1 CVD method of fabricate semiconductor • 5.4.2 Invalidity of Fickian diffusion • 5.5 Food production and cooking • 6 See also • 7 Citations • 8 Further reading • 9 External links History In 1855, physiologist Adolf Fick first reported Fick's experiments (modeled on Graham's) dealt with measuring the concentrations and fluxes of salt, diffusing between two reservoirs through tubes of water. It is n...

Stable Diffusion Online Stable Diffusion is a latent text-to-image diffusion model capable of generating photo-realistic images given any text input, cultivates autonomous freedom to produce incredible imagery, empowers billions of people to create stunning art within seconds. Create beautiful art using stable diffusion ONLINE for free. Frequently asked questions If you can’t find what you’re looking for, email our support team and if you’re lucky someone will get back to you. • • What was the Stable Diffusion model trained on? The underlying dataset for Stable Diffusion was the 2b English language label subset of LAION 5b https://laion.ai/blog/laion-5b/, a general crawl of the internet created by the German charity LAION. • What is the copyright for using Stable Diffusion generated images? The area of AI-generated images and copyright is complex and will vary from jurisdiction to jurisdiction. • Can artists opt-in or opt-out to include their work in the training data? There was no opt-in or opt-out for the LAION 5b model data. It is intended to be a general representation of the language-image connection of the Internet. • • Where can I access the Stable Diffusion Online website? https://stablediffusionweb.com • What is the copyright on images created through Stable Diffusion Online? Images created through Stable Diffusion Online are fully open source, explicitly falling under the CC0 1.0 Universal Public Domain Dedication. • What kinds of GPUs will be able to run Stable ...

What is Diffusion? Diffusion is the process of movement of molecules under a concentration gradient. It is an important process occurring in all living beings. Diffusion helps in the movement of substances in and out of the cells. The molecules move from a region of higher concentration to a region of lower concentration until the concentration becomes equal throughout. Liquid and gases undergo diffusion as the molecules are able to move randomly. Example: Take water in a beaker. Add a few copper sulfate crystals in one place and leave it as it is for some time without disturbing it. After some time we can see that the beaker contains a uniformly coloured solution. Here, both water and copper sulfate diffuse independently. With this experiment, we can infer that solutes move from a higher concentration to a lower concentration in a solution. Also Read: Recommended Video: Types of Diffusion Diffusion is widely used in various fields such as biology, physics, chemistry, etc. Diffusion can be classified into two main types: Simple diffusion and facilitated diffusion. Simple diffusion A process in which the substance moves through a semipermeable membrane or in a solution without any help from transport proteins.  For example, bacteria deliver small nutrients, water and oxygen into the cytoplasm through simple diffusion. Facilitated diffusion Facilitated diffusion is a passive movement of molecules across the cell membrane from the region of higher concentration to t...

Hast du dich schonmal gefragt, warum Tinte sich im Glas Wasser verteilt, Zucker sich im Tee auflöst, heiße Getränke so schnell abkühlen oder sich Gerüche im ganzen Raum verbreiten? Auf all diese Fragen gibt die Diffusion die richtige Antwort. Was Diffusion ist und wie sie abläuft verraten wir dir in diesem Artikel. Let’s go! Diffusion einfach erklärt Zellen in unserem Körper brauchen Stoffe von außen, um zu überleben. Sie müssen aber auch umgekehrt die Fähigkeit besitzen, Stoffe nach außen abzugeben. Das alles passiert über die Zellmembran, die die Zelle umgibt. Die Zellmembran ist aber nur für bestimmte Stoffe durchlässig. Andere hingegen werden von ihr einfach abgewiesen. Aus diesem Grund gibt es besondere Mechanismen, wodurch die abgewiesenen Moleküle trotzdem durch die Membran gelangen können. Ein besonderer Mechanismus ist die Diffusion. Für den Transport durch die Zellmembran gibt es 2 Möglichkeiten: • Aktiver Transport (es wird Energie hinzugegeben) • Passiver Transport (es wird keine Energie hinzugegeben) Beim passiven Transport gibt es zwei wichtige Mechanismen, die wir uns genauer angucken: • Diffusion • Osmose Was ist Diffusion? Die Diffusion bewirkt, dass sich Teilchen eines gelösten Stoffes gleichmäßig in einer Lösung verteilen. Und warum das Ganze? Die Natur versucht immer einen Konzentrationsausgleich zu kreieren. Deshalb verteilen sich die Stoffe dann so, dass sie überall gleich konzentriert sind. Der Stoff bewegt sich vom Ort der höheren Konzentration zum ...

• Diffusion is the passive movement of molecules from an area of high concentration to an area of low concentration. • Passive diffusion is the movement of molecules across a membrane, such as a cell membrane. The movement does not require energy. • In facilitated diffusion, a molecule is transported across a membrane with the help of a carrier protein. • Osmosis is a type of passive diffusion in which water diffuses across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration. • Respiration and photosynthesis are examples of naturally occurring diffusion processes. • Glucose movement into cells is an example of facilitated diffusion. • Water absorption in plant roots is an example of osmosis. What Is Osmosis? Water passing through a semi-permeable membrane by osmosis into a region of higher sugar concentration. ttsz/iStock/Getty Images Plus In osmosis, the direction of water flow is determined by solute concentration. Water diffuses from a hypotonic (low solute concentration) solution to a hypertonic (high solute concentration) solution. In the example above, water moves from the left side of the semi-permeable membrane, where the sugar concentration is low, to the right side of the membrane, where the sugar molecule concentration is higher. If the molecule concentration were the same on both sides of the membrane, water would flow equally ( isostonic) between both sides of the membrane. This image shows facilitated dif...

Have you been through airport security lately? If you have, you’ve probably noticed that it’s carefully designed to let some things in (such as passengers with tickets) and to keep others out (such as weapons, explosives, and bottled water). Flight attendants, captains, and airport personnel travel through quickly via a special channel, while regular passengers pass through more slowly, sometimes with a long wait in line. In many ways, airport security is a lot like the plasma membrane of a cell. Cell membranes are selectively permeable, regulating which substances can pass through, as well as how much of each substance can enter or exit at a given time. Selective permeability is essential to cells’ ability to obtain nutrients, eliminate wastes, and maintain a stable interior environment different than that of the surroundings (maintain homeostasis). The simplest forms of transport across a membrane are passive. Passive transport does not require the cell to expend any energy and involves a substance diffusing down its concentration gradient across a membrane. A concentration gradient is a just a region of space over which the concentration of a substance changes, and substances will naturally move down their gradients, from an area of higher to an area of lower concentration. In cells, some molecules can move down their concentration gradients by crossing the lipid portion of the membrane directly, while others must pass through membrane proteins in a process called facil...

Recent Examples on the Web The importance of establishing and maintaining rigorous syndromic surveillance sites, such as ProMed, to monitor emerging disease outbreaks, proliferation of antibiotic resistance genes, traveling of disease vectors, and their diffusion across country borders is more crucial than ever. — Rebecca Kreston, Discover Magazine, 20 Mar. 2011 As the researchers of the preprint note in their introduction: Drawing on the Swiss Cheese Model of Pandemic Defense, every layer of the healthcare AI ecosystem currently contains large holes that make the broad diffusion of poorly performing products inevitable. — Beth Mole, Ars Technica, 2 May 2023 Today, the apps are much better, thanks to diffusion models. — Ryan Cross, BostonGlobe.com, 1 Dec. 2022 This illustrates the subtle but important difference between cultural diffusion through flow of ideas vs. replacement of populations. — Razib Khan, Discover Magazine, 5 Sep. 2011 As mentioned before, zinc is also involved in the diffusion of taste stimuli in one's taste buds and is sometimes used as a treatment for taste disorders as a result. — Daryl Austin, USA TODAY, 6 May 2023 The smallest, ultra-fine particles are captured by diffusion (while zig-zagging the particle will eventually hit and stick to the fiber). — Rachel Rothman, Good Housekeeping, 2 May 2023 Latent diffusion models encode images and their text captions into vectors (basically a unique numerical representation for each image). — IEEE Spectrum, 27...

The rate of flow of the diffusing substance is found to be proportional to the concentration j is the amount of substance passing through a reference surface of unit area per unit time, if the coordinate x is perpendicular to this reference area, if c is the concentration of the substance, and if the constant of proportionality is D, then j = − D( dc/ dx); dc/ dx is the rate of change of concentration in the direction x, and the minus sign indicates the flow is from higher to lower concentration. D is called the This article was most recently revised and updated by