Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Solar Chemical
Solar chemical refers to a number of possible processes that harness solar energy by absorbing sunlight in a chemical reaction. The idea is conceptually similar to photosynthesis in plants, which converts solar energy into the chemical bonds of glucose molecules, but without using living organisms, which is why it is also called artificial photosynthesis. A promising approach is to use focused sunlight to provide the energy needed to split water into its constituent hydrogen and oxygen in the presence of a metallic catalyst such as zinc. This is normally done in a two-step process so that hydrogen and oxygen are not produced in the same chamber, which creates an explosion hazard. Another approach involves taking the hydrogen created in this process and combining it with carbon dioxide to create methane. The benefit of this approach is that there is an established infrastructure for transporting and burning methane for power generation, which is not true for hydrogen. One main drawback to both of these approaches is common to most methods of energy storage: adding an extra step between energy collection and electricity production drastically decreases the efficiency of the overall process.
  • 481
  • 22 Nov 2022
Topic Review
Moberly–Jourdain Incident
The Moberly–Jourdain incident (also the Ghosts of Petit Trianon or Versailles, French: les fantômes du Trianon / les fantômes de Versailles) is a claim of time travel and hauntings made by Charlotte Anne Moberly (1846–1937) and Eleanor Jourdain (1863–1924). In 1911, Moberly and Jourdain published a book entitled An Adventure under the names of "Elizabeth Morison" and "Frances Lamont". Their book describes a visit they made to the Petit Trianon, a small château in the grounds of the Palace of Versailles where they claimed to have seen the gardens as they had been in the late eighteenth century as well as ghosts, including Marie Antoinette and others. Their story caused a sensation and was subject to much ridicule.
  • 376
  • 22 Nov 2022
Topic Review
Drag
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path.
  • 1.3K
  • 22 Nov 2022
Biography
Daryl Chapin
Daryl Muscott Chapin[1] (21 July 1906 – 19 January 1995) was an American physicist, best known for co-inventing solar cells in 1954 during his work at Bell Labs alongside Calvin S. Fuller and Gerald Pearson. For this, he was inducted into the National Inventors Hall of Fame in 2008. Chapin was born in Ellensburg, Washington (state) on 21 July 1906, although he spent his childhood in Salem,
  • 787
  • 22 Nov 2022
Topic Review
Effective Atomic Number
Effective atomic number has two different meanings: one that is the effective nuclear charge of an atom, and one that calculates the average atomic number for a compound or mixture of materials. Both are abbreviated Zeff.
  • 2.0K
  • 22 Nov 2022
Biography
Norman Rasmussen
Norman C. Rasmussen (November 12, 1927 – July 18, 2003) was an American physicist.[1] Rasmussen was born in Harrisburg, Pennsylvania. He grew up on a dairy farm as the fifth of six brothers. He attended public school in Hershey, Pennsylvania. His father died when he was in eighth grade, and his family moved to Gettysburg, where his grandparents helped to care for the family. Rasmussen gradu
  • 468
  • 22 Nov 2022
Topic Review
Mooncake
A mooncake (simplified Chinese: 月饼; traditional Chinese: 月餅; pinyin: yuè bǐng; Jyutping: jyut6 beng2; Yale: yuht béng) is a Chinese bakery product traditionally eaten during the Mid-Autumn Festival (中秋節). The festival is for lunar appreciation and moon watching, when mooncakes are regarded as an indispensable delicacy. Mooncakes are offered between friends or on family gatherings while celebrating the festival. The Mid-Autumn Festival is one of the four most important Chinese festivals. Typical mooncakes are round pastries, measuring about 10 cm in diameter and 3–4 cm thick, and are commonly eaten in the Southern Chinese regions of Guangdong, Guangxi, Hong Kong and Macau. A rich thick filling usually made from red bean or lotus seed paste is surrounded by a thin (2–3 mm) crust and may contain yolks from salted duck eggs. Mooncakes are usually eaten in small wedges accompanied by tea. Today, it is customary for businessmen and families to present them to their clients or relatives as presents, helping to fuel a demand for high-end mooncakes. Due to China's influence, mooncakes and Mid-Autumn Festival are also enjoyed and celebrated in other parts of Asia. Mooncakes have also appeared in western countries as a form of delicacy.
  • 960
  • 22 Nov 2022
Topic Review
Triple-Alpha Process
The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon.
  • 2.0K
  • 22 Nov 2022
Topic Review
History of Solar System Formation and Evolution Hypotheses
The history of scientific thought about the Formation and evolution of the Solar System begins with the Copernican Revolution. The first recorded use of the term "Solar System" dates from 1704.
  • 2.8K
  • 22 Nov 2022
Topic Review
Simulation Argument (Coding Planck Units)
Coding Planck units for deep universe (Programmer God) Simulation Hypothesis models The deep universe simulation hypothesis or simulation argument is the argument that the universe in its entirety, down to the smallest detail, could be an artificial simulation, such as a computer simulation. A deep universe simulation begins with the big bang and is programmed by an external intelligence (external to the universe), this intelligence by definition a Programmer God in the creator of the universe context. In Big Bang cosmology, the Planck epoch or Planck era is the earliest stage of the Big Bang, where cosmic time was equal to Planck time. Thus for a deep universe simulation, Planck time can be used as the reference for the simulation clock-rate, with the simulation operating at or below the Planck scale, and with the Planck units as (top-level) candidates for the base (mass, length, time, charge) units.
  • 490
  • 22 Nov 2022
  • Page
  • of
  • 130
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Video Production Service
Feedback