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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.
  • 901
  • 22 Nov 2022
Biography
Richard Gaitskell
Richard Jeremy Gaitskell (born May 2, 1965) is a physicist and professor at Brown University, and a leading scientist in the search for particle dark matter.[1] He is co-founder, a principal investigator, and co-spokesperson of the Large Underground Xenon (LUX) experiment, which announced world-leading[2][3] first results on October 30, 2013. He is also a leading investigator in the new LUX-Zepl
  • 897
  • 09 Dec 2022
Topic Review
Guru Purnima
Guru Purnima (Poornima) is an eastern spiritual tradition dedicated to spiritual and academic teachers, who are evolved or enlightened humans, ready to share their wisdom, with very little or no monetary expectation, based on Karma Yoga. It is celebrated as a festival in Nepal by the Nepalese Hindus and Buddhists. This festival is traditionally observed by Hindus, Buddhists and Jains to revere their chosen spiritual teachers / leaders and express their gratitude. The festival is celebrated on the full moon day (Purnima) in the Hindu month of Ashadha (June–July) as it is known in the Hindu calendar of India and Nepal. This day marks the first peak of the lunar cycle after the peak of the solar cycle.
  • 895
  • 17 Oct 2022
Topic Review
K-Theory
In string theory, K-theory classification refers to a conjectured application of K-theory (in abstract algebra and algebraic topology) to superstrings, to classify the allowed Ramond–Ramond field strengths as well as the charges of stable D-branes. In condensed matter physics K-theory has also found important applications, specially in the topological classification of topological insulators, superconductors and stable Fermi surfaces ((Kitaev 2009), (Horava 2005)).
  • 892
  • 30 Nov 2022
Topic Review Peer Reviewed
Fundamentals of Water Radiolysis
Radiolysis of water and aqueous solutions refers to the decomposition of water and its solutions under exposure to ionizing radiation, such as γ-rays, X-rays, accelerated particles, or fast neutrons. This exposure leads to the formation of highly reactive species, including free radicals like hydroxyl radicals (●OH), hydrated electrons (e−aq), and hydrogen atoms (H●), as well as molecular products like molecular hydrogen (H2) and hydrogen peroxide (H2O2). These species may further react with each other or with solutes in the solution. The yield and behavior of these radiolytic products depend on various factors, including pH, radiation type and energy, dose rate, and the presence of dissolved solutes such as oxygen or ferrous ions, as in the case of the ferrous sulfate (Fricke) dosimeter. Aqueous radiation chemistry has been pivotal for over a century, driving advancements in diverse fields, including nuclear science and technology—particularly in water-cooled reactors—radiobiology, bioradical chemistry, radiotherapy, food preservation, wastewater treatment, and the long-term management of nuclear waste. This field is also vital for understanding radiation effects in space.
  • 887
  • 10 Mar 2025
Biography
Leland John Haworth
Leland John Haworth (July 11, 1904 – March 5, 1979) was an United States of America particle physicist. In his long career he was head of the Brookhaven National Laboratory, the Atomic Energy Commission, the National Science Foundation, and was assistant to the president of Associated Universities, Inc.[1] Haworth was born in Flint, Michigan, although his parents were normally living in New
  • 882
  • 27 Dec 2022
Topic Review
Area Codes
Today, the North American Numbering Plan continues to create new area codes as demand increases for local lines in cities and regions nationwide. When a new area code is added, customers
  • 881
  • 26 Aug 2024
Topic Review
Dref Friction Spinning
Friction Spinning or Dref Spinning is a textile technology that suitable for spinning coarse counts of yarns and technical core-wrapped yarns. Dref yarns are bulky, with low tensile strength making them suitable for blankets and mop yarns, they can be spun from asbestos, carbon fibres and make filters was water systems.[clarification needed] Yarns such as Rayon and Kevlar can be spun using this method. The technology was developed around 1975 by Dr. Ernst Fehrer.
  • 879
  • 14 Oct 2022
Biography
Jürgen Kurths
Jürgen Kurths (born 11 March 1953 in Arendsee/Altmark) is a German physicist and mathematician. He is a chair of the research department Complexity Sciences of the Potsdam Institute for Climate Impact Research, a Professor of Nonlinear Dynamics at the Institute of Physics at the Humboldt University, Berlin, and a 6th-century chair for Complex Systems Biology at the Institute for Complex Systems
  • 870
  • 12 Dec 2022
Topic Review
Plasma Medicine
Plasma medicine is an emerging field that combines plasma physics, life sciences and clinical medicine. It is being studied in disinfection, healing, and cancer. Most of the research is in vitro and in animal models. It uses ionized gas (physical plasma) for medical uses or dental applications. Plasma, often called the fourth state of matter, is an ionized gas containing positive ions and negative ions or electrons, but is approximately charge neutral on the whole. The plasma sources used for plasma medicine are generally low temperature plasmas, and they generate ions, chemically reactive atoms and molecules, and UV-photons. These plasma-generated active species are useful for several bio-medical applications such as sterilization of implants and surgical instruments as well as modifying biomaterial surface properties. Sensitive applications of plasma, like subjecting human body or internal organs to plasma treatment for medical purposes, are also possible. This possibility is being heavily investigated by research groups worldwide under the highly-interdisciplinary research field called 'plasma medicine'.
  • 869
  • 27 Oct 2022
Biography
Robert K. Logan
Robert K. Logan (born August 31, 1939), originally trained as a physicist, is a media ecologist. He received from MIT a BS in 1961 and a PhD in 1965 under the supervision of Francis E. Low. After two post-doctoral appointments as a Research Associate at the University of Illinois at Urbana-Champaign (1965-7) and the University of Toronto (1967-8), he became a physics professor in 1968 at Toro
  • 865
  • 27 Dec 2022
Topic Review
Per- and Polyfluoroalkyl Substances (PFAS) Sorption
Per- and polyfluorinated alkyl substances (PFAS) are an environmentally persistent group of chemicals that can pose an imminent threat to human health through groundwater and surface water contamination. The primary adsorption mechanisms identified in the literature are electrostatic interactions and hydrophobic interactions.
  • 862
  • 18 Jul 2023
Biography
R. Orin Cornett
R. Orin Cornett (November 13, 1913 – December 7, 2002) was an American physicist, university professor and administrator, and the inventor of a literacy system for the deaf, known as Cued Speech. R. (Richard) Orin Cornett was born in Driftwood, Oklahoma, a now unincorporated town near the Kansas border located in Alfalfa County, on November 14, 1913.[1] He earned his BS degree in Mathematic
  • 858
  • 27 Dec 2022
Topic Review
Interference Reflection Microscopy
Interference reflection microscopy (IRM) is an optical microscopy technique that utilizes polarized light to form an image of an object on a glass surface. The intensity of the signal is a measure of proximity of the object to the glass surface. This technique can be used to study events at the cell membrane without the use of a (fluorescent) label in contrast to TIRF microscopy.
  • 841
  • 21 Nov 2022
Biography
Bruno Augenstein
Bruno Wilhelm Augenstein (March 16, 1923 – July 6, 2005) was a Germany -born mathematician and physicist who made important contributions in space technology, ballistic missile research, satellites, antimatter, and many other areas. Augenstein worked in the Aerophysics Laboratory at North American Aviation on diverse projects including weaponization of the V-2 rocket, a ramjet-powered vehic
  • 835
  • 09 Dec 2022
Topic Review
Physical Phenomenology
After a brief digression on the current landscape of theoretical physics and on some open questions pertaining to coherence with experimental results, still to be settled, it is shown that the properties of the deformed Minkowski space lead to a plurality of potential physical phenomena that should occur, provided that the resulting formalisms can be considered as useful models for the description of some aspects of physical reality. 
  • 832
  • 27 Apr 2021
Topic Review
Gloss Measurements
The appearance of a surface depends on four main appearance attributes, namely color, gloss, texture, and translucency. Gloss is an important attribute that people use to understand surface appearance, right after color.
  • 819
  • 03 Jan 2024
Topic Review
Fresnel Imager
A Fresnel imager is a proposed ultra-lightweight design for a space telescope that uses a Fresnel array as primary optics instead of a typical lens. It focuses light with a thin opaque foil sheet punched with specially shaped holes, thus focusing light on a certain point by using the phenomenon of diffraction. Such patterned sheets, called Fresnel zone plates, have long been used for focusing laser beams, but have so far not been used for astronomy. No optical material is involved in the focusing process as in traditional telescopes. Rather, the light collected by the Fresnel array is concentrated on smaller classical optics (e.g. 1/20th of the array size), to form a final image. The long focal lengths of the Fresnel imager (a few kilometers) require operation by two-vessel formation flying in space at the L2 Sun-Earth Lagrangian point. In this two spacecraft formation-flying instrument, one spacecraft holds the focussing element: the Fresnel interferometric array; the other spacecraft holds the field optics, focal instrumentation, and detectors.
  • 815
  • 01 Nov 2022
Topic Review
Sugar as Snow Analog in Penetration Testing
Understanding the mechanical properties of snow and ice is necessary for the efficient design and construction of cold regions infrastructure. Testing and evaluation is most commonly undertaken in situ or using samples within cold labs. However, there is an inevitable uncertainty as to the accuracy of results obtained from ex situ testing. Therefore, development of suitable proxies for snow, such as sugar or foam, is valuable, potentially enabling further research in this field.
  • 807
  • 06 Apr 2022
Topic Review
Detection System for DDoS Attacks
Distributed Denial of Service (DDoS) attacks, advanced persistent threats, and malware actively compromise the availability and security of Internet services. A DDoS attack is a vindictive attempt from numerous frameworks to make PC/network assets inaccessible to its expected clients, more often than not, by blocking/interrupting services associated with the organization of the network/Internet.
  • 804
  • 29 Dec 2023
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