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Heat Modulation of Intrinsic MR Contrasts

Multi-parametric magnetic resonance imaging (MRI) is a paradigm that combines several MR imaging contrast types to provide added layers of information for the characterization of tissue types, including benign and malignant tumors.

322
28 Feb 2022

Biography

Harry Charles Kelly (9 October 1908—2 February 1976)[1] was an American physicist best known for his role in Japan in the aftermath of World War II in preserving scientific research not related to weaponry. He forged enduring relations between the U.S. and Japanese scientific communities, recognized by the Japanese government. Upon his death in 1976, the Japanese government requested a porti

327
13 Dec 2022

Biography

Hans-Peter Dürr

Hans-Peter Dürr (7 October 1929 – 18 May 2014) was a German physicist. He worked on nuclear and quantum physics, elementary particles and gravitation, epistemology, and philosophy, and he has advocated responsible scientific and energy policies.[1] In 1987, he was awarded the Right Livelihood Award for "his profound critique of the Strategic Defense Initiative (SDI) and his work to convert hi

662
17 Nov 2022

Biography

Hans Kopfermann

Hans Kopfermann (26 April 1895, in Breckenheim near Wiesbaden – 28 January 1963, in Heidelberg) was a Germany atomic and nuclear physicist. He devoted his entire career to spectroscopic investigations, and he did pioneering work in measuring nuclear spin. During World War II, he worked on the German nuclear energy project, also known as the Uranium Club. Kopfermann began his studies at the

599
29 Nov 2022

Topic Review

Halide Perovskites Films for Ionizing Radiation Detection

Halide perovskites are a novel class of semiconductors that have attracted great interest due to their peculiar properties of interest for optoelectronics. In fact, their use ranges from the field of sensors and light emitters to ionizing radiation detectors. Since 2015, ionizing radiation detectors exploiting perovskite films as active media have been developed.

286
15 Jun 2023

Topic Review

A half reaction (or half-cell reaction) is either the oxidation or reduction reaction component of a redox reaction. A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction. Often, the concept of half reactions is used to describe what occurs in an electrochemical cell, such as a Galvanic cell battery. Half reactions can be written to describe both the metal undergoing oxidation (known as the anode) and the metal undergoing reduction (known as the cathode). Half reactions are often used as a method of balancing redox reactions. For oxidation-reduction reactions in acidic conditions, after balancing the atoms and oxidation numbers, one will need to add H+ ions to balance the hydrogen ions in the half reaction. For oxidation-reduction reactions in basic conditions, after balancing the atoms and oxidation numbers, first treat it as an acidic solution and then add OH− ions to balance the H+ ions in the half reactions (which would give H2O).

3.2K
28 Nov 2022

Topic Review

Gyrotrons are among the most powerful sources of coherent radiation that operate in CW and long pulse regimes in the sub-THz and the THz frequency ranges of the electromagnetic spectrum, i.e. between 0.3 THz and 3.0 THz (corresponding to wavelengths from 1.0 to 0.1 mm). This region, which spans between the frequency bands occupied by various electronic and photonic devices, respectively, is habitually called a THz power gap. The underlying mechanism of the operation of the gyrotron involves a formation of bunches of electrons gyrating in a helical electron beam and their synchronous interaction with a fast (i.e. having a superluminal phase velocity) electromagnetic wave, producing a bremsstrahlung radiation. In contrast to the slow-wave tubes, which utilize tiny structures with dimensions comparable to the wavelength of the radiation, the gyrotrons have a simpler resonant system (cavity resonator) with dimensions that are much greater than the wavelength. This allows much more powerful electron beams to be used and thus higher output powers to be achieved. Although in comparison with the classical microwave tubes the gyrotrons are characterized by greater volume and weight due to the presence of bulky parts (such as superconducting magnets and massive collectors where the energy of the spent electron beam is dissipated) they are much more compact and can easily be embedded in a sophisticated laboratory equipment (e.g. spectrometers, technological systems, etc.) than other devices such as free-electron lasers (FEL) and radiation sources based on electron accelerators. Nowadays, the gyrotrons are used as powerful sources of coherent radiation in the wide fields of high-power sub-THz and THz science and technologies [1][2][3].

1.9K
29 Oct 2020

Biography

Gustav Heinrich Wiedemann

Gustav Heinrich Wiedemann (German pronunciation: [ˈhaɪ̯nʁɪç ˈɡʊsta(ː)f ˈviːdəman];[1][2]) FRS(For) HFRSE (2 October 1826 – 24 March 1899) was a German physicist and scientific author. Wiedemann was born in Berlin the son of a merchant who died two years later. Following the death of his mother in 1842 he lived with his grandparents.[3] After attending a private school as well

527
12 Dec 2022

Topic Review

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.

242
17 Oct 2022

Biography

Günter Nimtz (born 22 September 1936) is a German physicist, working at the 2nd Physics Institute at the University of Cologne in Germany. He has investigated narrow-gap semiconductors and liquid crystals and was engaged in several interdisciplinary studies on the effect of non-ionizing electromagnetic radiation in biological systems. His international reputation mainly results from experiments

819
29 Dec 2022

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