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Eutectic bonding, also referred to as eutectic soldering, describes a wafer bonding technique with an intermediate metal layer that can produce a eutectic system. Those eutectic metals are alloys that transform directly from solid to liquid state, or vice versa from liquid to solid state, at a specific composition and temperature without ...
A eutectic system or eutectic mixture (/ j uː ˈ t ɛ k t ɪ k / yoo-TEK-tik) [1] is a type of a homogeneous mixture that has a melting point lower than those of the constituents. [2] The lowest possible melting point over all of the mixing ratios of the constituents is called the eutectic temperature .
The possibility of life-forms being based on "alternative" biochemistries is the topic of an ongoing scientific discussion, informed by what is known about extraterrestrial environments and about the chemical behaviour of various elements and compounds. It is of interest in synthetic biology and is also a common subject in science fiction.
The primary use of the chemoton model is in the study of the chemical origin of life. This is because the chemoton itself can be thought of as a primitive or minimal cellular life as it satisfies the definition of what a cell is (that it is a unit of biological activity enclosed by a membrane and capable of self-reproduction).
The structure of the ribosome has been called the "smoking gun", with a central core of RNA and no amino acid side chains within 18 Å of the active site that catalyzes peptide bond formation. [188] [184] [189] The concept of the RNA world was proposed in 1962 by Alexander Rich, [190] and the term was coined by Walter Gilbert in 1986.
Each phase has a characteristic arrangement of atoms. X-ray or neutron diffraction can be used to identify which structures are present in the material, and thus which compounds are present. Crystallography covers the enumeration of the symmetry patterns which can be formed by atoms in a crystal and for this reason is related to group theory
Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition of ligand in metalorganic and inorganic chemistry , in biochemistry it is ambiguous whether the ligand generally binds at a metal site, as is the case in hemoglobin .
The first description of cooperative binding to a multi-site protein was developed by A.V. Hill. [4] Drawing on observations of oxygen binding to hemoglobin and the idea that cooperativity arose from the aggregation of hemoglobin molecules, each one binding one oxygen molecule, Hill suggested a phenomenological equation that has since been named after him: