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6 天前 · Obsessive–compulsive disorder ( OCD) is a mental and behavioral disorder in which an individual has intrusive thoughts (an obsession) and feels the need to perform certain routines ( compulsions) repeatedly to relieve the distress caused by the obsession, to the extent where it impairs general function. [1] [2] [7]
6 天前 · Paracetamol (acetaminophen[a]) is a non-opioid analgesic and antipyretic agent used to treat fever and mild to moderate pain.[13][14][15] It is a widely used over the counter medication. Common brand names include Tylenol and Panadol. At a standard dose, paracetamol only slightly reduces fever;[14][16][17] it is inferior to ibuprofen in that ...
5 天前 · The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
6 天前 · Formaldehyde ( / fɔːrˈmældɪhaɪd / ⓘ for-MAL-di-hide, US also / fər -/ ⓘ fər-) ( systematic name methanal) is an organic compound with the chemical formula CH2O and structure H−CHO, more precisely H2C=O. The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde.
5 天前 · The United Nations Educational, Scientific and Cultural Organization ( UNESCO) [a] is a specialized agency of the United Nations (UN) with the aim of promoting world peace and security through international cooperation in education, arts, sciences and culture. [2] [3] It has 194 member states and 12 associate members, [4] as well as partners in ...
5 天前 · Quantum System One, a quantum computer by IBM from 2019 with 20 superconducting qubits A quantum computer is a computer that takes advantage of quantum mechanical phenomena. On small scales, physical matter exhibits properties of both particles and waves, and quantum computing leverages this behavior, specifically quantum superposition and entanglement, using specialized hardware that supports ...
5 天前 · Wireless LAN (WLAN) channels are frequently accessed using IEEE 802.11 protocols. The 802.11 standard provides several radio frequency bands for use in Wi-Fi communications, each divided into a multitude of channels numbered at 5 MHz spacing (except in the 45/60 GHz band, where they are 0.54/1.08/2.16 GHz apart) between the centre frequency of the channel.
