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An electroluminescent display (EL display) is a type of flat panel display technology that produces light through the process of electroluminescence. In an electroluminescent material, when an electric current is applied, it emits light as a result of the recombination of electrons and holes in a semiconductor material.
Electroluminescence is the phenomenon where a material emits light in response to an electric current or a strong electric field. This process occurs in certain materials, typically semiconductors, which are capable of producing light when they are energized by electricity. In simple terms, when an electric voltage is applied to these materials, electrons within the semiconductor become excited and move to higher energy levels.
Electric discharge refers to the flow of electric current through a medium, typically resulting from the breakdown of an insulating material or the movement of charge carriers in a conductive path. This phenomenon can occur in various forms and contexts, such as: 1. **Spark Discharge**: A quick, localized discharge of electricity that occurs when a high voltage exceeds the breakdown voltage of the surrounding medium (such as air), resulting in a visible spark.
An electret is a dielectric material that has a quasi-permanent electric charge or dipole polarization. It behaves similarly to a permanent magnet, but for electric fields instead of magnetic fields. Electrets are typically made from polymers or ceramics that are electrically polarized during their manufacturing process. Electrets can be used in various applications, including: 1. **Microphones**: Electret condenser microphones utilize electrets to maintain a steady electric field, which helps convert sound waves into electrical signals.
Einstein–Hopf drag, also known simply as "Hopf drag," refers to a phenomenon in theoretical physics that arises in the context of general relativity and the motion of rotating masses. The term is often associated with the effects that a rotating mass has on the inertial frames of reference around it, particularly in relation to the way the rotation influences the motion of nearby objects.
Dielectric Barrier Discharge (DBD) is a type of electrical discharge that occurs when a high-voltage electric field is applied across two electrodes separated by a dielectric (insulating) material. This technology has various applications in fields such as plasma generation, surface treatment, and environmental engineering. Here’s a detailed breakdown of DBD: 1. **Mechanism**: - In a DBD setup, at least one of the electrodes is covered by a dielectric material.
The Dember effect refers to a phenomenon observed in psychophysics, particularly in the study of perception and attention. Named after the psychologist William Dember, this effect describes how the presence of a secondary task or stimulus can influence the performance on a primary task, often enhancing or impairing it.
The term "dawn chorus" commonly refers to the natural phenomenon observed in the early morning, particularly at sunrise, when various bird species sing collectively as they begin their day. However, in the context of electromagnetic phenomena, "dawn chorus" refers to a specific type of electromagnetic wave activity that occurs in Earth's magnetosphere. The electromagnetic dawn chorus is characterized by a series of rising and falling frequency sounds produced by plasma waves in the Earth's magnetosphere.
"Conductor clashing" typically refers to a situation in orchestral or musical contexts where two conductors have conflicting interpretations or approaches to a piece of music. This can happen during rehearsals or performances when different conductors have differing opinions on tempo, dynamics, interpretation, or cues, potentially leading to confusion among musicians. In a broader sense, conductor clashing can also describe any scenario where two leaders or authority figures in an organization or group conflict in their direction, creating disarray and inefficiency.
Compact intracloud discharge (CID) refers to a type of electrical discharge that occurs within a thunderstorm cloud, specifically between different regions of the cloud itself, rather than between the cloud and the ground or between separate clouds. These discharges are often shorter and more compact than typical cloud-to-ground lightning strikes. CIDs are characterized by their localized nature and can occur within the complex structure of the cloud, which consists of various charged regions.
Burns temperature, also known as the "Burns temperature," refers to a specific temperature, often used in the context of engineering and materials science, that indicates the onset of chemical reactions or degradation of materials, particularly polymers or organic compounds. It is critical in various applications, including fire safety, material selection, and understanding combustion processes.
Antiferroelectricity is a material property observed in certain crystalline substances where the electric dipoles in neighboring units align in opposite directions, resulting in a state that does not have a net polarization. In antiferroelectric materials, the dipolar moments cancel each other out, unlike ferroelectric materials where the dipoles align in the same direction, resulting in a net spontaneous polarization.
Aeronomy is the study of the Earth's upper atmosphere, particularly the regions where the atmosphere begins to interact with outer space. This field encompasses research into the physical and chemical processes that influence the behavior and composition of the atmosphere at high altitudes, typically above 30 to 50 kilometers (19 to 31 miles), where phenomena like the ionosphere and various layers of the atmosphere, including the thermosphere and exosphere, are located.
Piezoelectric materials are substances that exhibit the piezoelectric effect, which is the ability to generate an electric charge in response to applied mechanical stress. This phenomenon occurs in certain materials when they undergo deformation, causing a separation of positive and negative charges within the material, thus creating an electric field. Key features of piezoelectric materials include: 1. **Types of Materials**: Common piezoelectric materials include certain crystals (e.g., quartz, topaz), ceramics (e.g.
The Hall effect is a phenomenon observed in electrical conductors and semiconductors when they are placed in a magnetic field perpendicular to the direction of an electric current. It was discovered by Edwin Hall in 1879. When a current-carrying conductor is subjected to a magnetic field, the motion of the charged particles (such as electrons) in the conductor is affected by the magnetic field.
Electrical breakdown refers to the phenomenon that occurs when an insulating material becomes conductive due to the application of a sufficient electric field. When the electric field strength exceeds a critical threshold, electrons are stripped from their atoms within the insulating material, leading to a sudden increase in conductivity and the formation of a plasma or a conducting path through the material. This can result in an uncontrolled flow of electricity, often leading to catastrophic failure of electrical devices, arcing, or damage to the insulating material.
Charge carriers are particles that carry an electric charge and are responsible for the conduction of electric current in a material. There are primarily two types of charge carriers: 1. **Electrons**: Negatively charged particles that can move freely in conductive materials (such as metals) to create an electric current. 2. **Holes**: These are the absence of electrons in a semiconductor material and can be considered as positively charged carriers.
A spark-gap transmitter is an early type of radio transmitter that uses a spark gap to create radio frequency (RF) signals. It was one of the first practical methods of generating radio waves for wireless communication, primarily used in the late 19th and early 20th centuries.
A Mercury-arc valve is a type of electrical switch that utilizes a pool of mercury to create an electrical conductive path. It is an early form of a semiconductor device that was used primarily in high-power applications, particularly in the field of power electronics. Here are some key features of mercury-arc valves: 1. **Construction**: The valve consists of a sealed container filled with mercury. When electrical voltage is applied, the mercury can be vaporized, creating an arc that conducts electricity.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.Figure 3. Visual Studio Code extension installation.Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. - Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact





