Topic Review
Mensa
Mensa is a faint constellation in the southern celestial hemisphere, first introduced by the French astronomer Nicolas Louis de Lacaille in the 18th century. It is named after the Table Mountain in South Africa.
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  • 15 Mar 2024
Topic Review
MEMS-Based Tunable Metamaterials
Micro-electro-mechanical systems (MEMS) is a well-known technology that mechanically reconfigures the metamaterial unit cells.
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  • 18 Jan 2022
Topic Review
MEMS Bionic Fish Ear Structure
The sensor is fabricated using microelectromechanical systems (MEMS) technology, and is encapsulated in castor oil, which has an acoustic impedance close to the human body.
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  • 27 Jan 2022
Topic Review
MEMS Acoustic Emission Sensors
Micro-electro-mechanical-systems (MEMS) acoustic emission (AE) sensors are designed to detect active defects in materials with the transduction mechanisms of piezoresistivity, capacitance or piezoelectricity. The majority of MEMS AE sensors are designed as resonators to improve the signal-to-noise ratio. The fundamental design variables of MEMS AE sensors include resonant frequency, bandwidth/quality factor and sensitivity. Micromachining methods have the flexibility to tune the sensor frequency to a particular range, which is important, as the frequency of AE signal depends on defect modes, constitutive properties and structural composition.
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  • 22 Dec 2020
Topic Review
Medical Uses of Silver
The medical uses of silver include its use in wound dressings, creams, and as an antibiotic coating on medical devices. Wound dressings containing silver sulfadiazine or silver nanomaterials may be used to treat external infections. The limited evidence available shows that silver coatings on endotracheal breathing tubes may reduce the incidence of ventilator-associated pneumonia. There is tentative evidence that using silver-alloy indwelling catheters for short-term catheterizing will reduce the risk of catheter-acquired urinary tract infections. Silver generally has low toxicity, and minimal risk is expected when silver is used in approved medical applications. Alternative medicine products such as colloidal silver are not safe or effective.
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  • 24 Oct 2022
Topic Review
Mechanistic Organic Photochemistry
Some chemical reactions take place by the action of light. These are called, "photochemical reactions", or "photolysis". Mechanistic organic photochemistry is the aspect of organic photochemistry which seeks to explain the mechanisms of organic photochemical reactions. The absorption of ultraviolet light by organic molecules often leads to reactions. In the earliest days, sunlight was employed, while in more modern times ultraviolet lamps are employed. Organic photochemistry has proven to be a very useful synthetic tool. Complex organic products can be obtained simply. Over the last century and earlier an immense number of photochemical reactions have been uncovered. In modern times the field is quite well understood and is used in organic synthesis and industrially. The utility of organic photochemistry has arisen only by virtue of the available mechanistic treatment; reactions which appear unlikely in ground-state understanding become understandable and accessible in terms of electronic excited-state consideration.
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  • 17 Nov 2022
Topic Review
Mechanisms of Co-Evolution of Wheat and Rust Pathogens
Wheat (Triticum spp.) is a cereal crop domesticated >8000 years ago and the second-most-consumed food crop nowadays. Ever since mankind has written records, cereal rust diseases have been a painful awareness in antiquity documented in the Old Testament (about 750 B.C.). The pathogen causing the wheat stem rust disease is among the first identified plant pathogens in the 1700s, suggesting that wheat and rust pathogens have co-existed for thousands of years. With advanced molecular technologies, wheat and rust genomes have been sequenced, and interactions between the host and the rust pathogens have been extensively studied at molecular levels.
  • 330
  • 08 Jun 2023
Topic Review
Mechanism of Surface-Enhanced Raman Spectroscopy
Raman spectroscopy is an analytical technique discovered by the Indian scientist C.V. Raman. It can be applied to analyze the molecular structure based on the molecular vibration and rotation information of scattering spectra. Benefiting from the recent advancements in material science, nanotechnology and optical technology, surface-enhanced Raman scattering (SERS) was developed and widely used in bioanalysis, clinical diagnosis and biomedical research. In SERS, Raman signals of molecules can be enhanced by six to ten orders of magnitude, owing to the electromagnetic field enhancement and chemical enhancement effects generated by nanostructures. The detection limit of SERS is even as low as the single-molecule level, so SERS is regarded as an ultrasensitive technique.
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  • 21 Mar 2023
Topic Review
Mechanical Properties of BCC-Structured High-Entropy Alloys
A new metallurgical strategy was introduced to develop advanced materials with outstanding performance—high-entropy alloys (HEAs). Today, HEAs contain five or more multiple principle metallic elements in equal or near-equal atomic percentages. HEAs’ four core effects—high configurational entropy, sluggish diffusion, severe lattice distortion, and the cock-tail effect—are mainly responsible for their various physical and mechanical properties. HEAs present promising properties, such as high strength and fracture toughness at room temperature and high temperatures and have excellent wear resistance, and corrosion resistance, along with high-temperature oxidation.
  • 2.0K
  • 28 Mar 2022
Topic Review
Measurement of Compact Muon Solenoid Magnetic Field
The Compact Muon Solenoid (CMS) is a general-purpose detector at the Large Hadron Collider. The goal of CMS experiment is to investigate a wide range of physics, including the search for the Higgs boson, extra dimensions, and particles that could make up dark matter. The CMS magnetic field is provided by a wide-aperture superconducting thin solenoid with a diameter of 6 m and a length of 12.5 m, where a central magnetic flux density of 3.8 T is created by an operational direct current of 18.164 kA.
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  • 15 Feb 2022
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