From Middle English gayn, gain, gein (“profit, advantage”), from Old Norse gagn (“benefit, advantage, use”), from Proto-Germanic *gagną, *gaganą (“gain, profit", literally "return”), from Proto-Germanic *gagana (“back, against, in return”), a reduplication of Proto-Germanic *ga- (“with, together”), from Proto-Indo-European *ḱóm (“next to, at, with, along”). Cognate with Icelandic gagn (“gain, advantage, use”), Swedish gagn (“benefit, profit”), Danish gavn (“gain, profit, success”), Gothic 𐌲𐌰𐌲𐌴𐌹𐌲𐌰𐌽 (gageigan, “to gain, profit”), Old Norse gegn (“ready”), dialectal Swedish gen (“useful, noteful”), Latin cum (“with”); see gain-, again, against. Compare also Middle English gaynen, geinen (“to be of use, profit, avail”), Icelandic and Swedish gagna (“to avail, help”), Danish gavne (“to benefit”).
The Middle English word was reinforced by Middle French gain (“gain, profit, advancement, cultivation”), from Old French gaaing, gaaigne, gaigne, a noun derivative of gaaignier (“to till, earn, win”), from Frankish *waidanjan (“to pasture, graze, hunt for food”), ultimately from Proto-Germanic *waiþiz, *waiþō, *waiþijō (“pasture, field, hunting ground”); compare Old High German weidōn, weidanōn (“to hunt, forage for food”) (Modern German Weide (“pasture”)), Old Norse veiða (“to catch, hunt”), Old English wǣþan (“to hunt, chase, pursue”). Related to wathe, wide.
gain (third-person singular simple present gains, present participle gaining, simple past and past participle gained)
(transitive) To acquire possession of.
(transitive, dated) To come off winner or victor in; to be successful in; to obtain by competition.
to gain a battle; to gain a case at law
(transitive) To increase.
(intransitive) To be more likely to catch or overtake an individual.
I'm gaining (on you).
gain ground
(transitive) To reach.
to gain the top of a mountain
In glaciology, an ice cap is a mass of ice that covers less than 50,000 km2 (19,000 sq mi) of land area (usually covering a highland area). Larger ice masses covering more than 50,000 km2 (19,000 sq mi) are termed ice sheets.
Ice sheets are bigger than ice shelves or alpine glaciers. Masses of ice covering less than 50,000 km2 are termed an ice cap.
Mass crystallization is the nucleation and growth of a large number of usually small crystals (~10−3–10−1 cm) in one and the same area of space. Examples of it are the formation of metal ingots and kidney stones, the solidification of concrete, and the production of granulated fertilizers, medicines, sugar, and salt.
At the present day, ultrafine soot particles have become the object of increasing attention due to their well-documented adverse effects on human health and climate. In particular, understanding soot nucleation is one of the most challenging problems toward a more controlled and cleaner combustion. Detailed information on the chemistry of nascent soot particles (NSPs) is expected to provide clues on the soot formation and growth reaction pathways. Herein, the early steps of soot formation in flames are addressed by investigating the chemical composition of NSPs and their molecular precursors by secondary ion mass spectrometry.
Secondary-ion mass spectrometry (SIMS) is a technique used to analyze the composition of solid surfaces and thin films by sputtering the surface of the specimen with a focused primary ion beam and collecting and analyzing ejected secondary ions. The mass/charge ratios of these secondary ions are measured with a mass spectrometer to determine the elemental, isotopic, or molecular composition of the surface to a depth of 1 to 2 nm. Due to the large variation in ionization probabilities among elements sputtered from different materials, comparison against well-calibrated standards is necessary to achieve accurate quantitative results. SIMS is the most sensitive surface analysis technique, with elemental detection limits ranging from parts per million to parts per billion.
In 1910 British physicist J. J. Thomson observed a release of positive ions and neutral atoms from a solid surface induced by ion bombardment.[1] Improved vacuum pump technology in the 1940s enabled the first prototype experiments on SIMS by Herzog and Viehböck[2] in 1949, at the University of Vienna, Austria.
In the mid-1950s Honig constructed a SIMS instrument at RCA Laboratories in Princeton, New Jersey.[3] Then in the early 1960s two SIMS instruments were developed independently.
One was an American project, led by Liebel and Herzog, which was sponsored by NASA at GCA Corp, Massachusetts, for analyzing moon rocks,[4] the other at the University of Paris-Sud in Orsay by R. Castaing for the PhD thesis of G. Slodzian.[5] These first instruments were based on a magnetic double focusing sector field mass spectrometer and used argon for the primary beam ions.
In the 1970s, K. Wittmaack and C. Magee developed SIMS instruments equipped with quadrupole mass analyzers.[6][7] Around the same time, A. Benninghoven introduced the method of static SIMS, where the primary ion current density is so small that only a negligible fraction (typically 1%) of the first surface layer is necessary for surface analysis.[8] Instruments of this type use pulsed primary ion sources and time-of-flight mass spectrometers and were developed by Benninghoven, Niehuis and Steffens at the University of Münster, Germany and also by Charles Evans & Associates.
The Castaing and Slodzian design was developed in the 1960s by the French company CAMECA S.A.S. and used in materials science and surface science.[citation needed] Recent developments are focusing on novel primary ion species like C60+, ionized clusters of gold and bismuth,[9] or large gas cluster ion beams (e.g., Ar700+).[10] The sensitive high-resolution ion microprobe (SHRIMP) is a large-diameter, double-focusing SIMS sector instrument based on the Liebl and Herzog design, and produced by Australian Scientific Instruments in Canberra, Australia
Depending on the SIMS type, there are three basic analyzers available: sector, quadrupole, and time-of-flight. A sector field mass spectrometer uses a combination of an electrostatic analyzer and a magnetic analyzer to separate the secondary ions by their mass-to-charge ratio. A quadrupole mass analyzer separates the masses by resonant electric fields, which allow only the selected masses to pass through. The time of flight mass analyzer separates the ions in a field-free drift path according to their velocity. Since all ions possess the same kinetic energy the velocity and therefore time of flight varies according to mass. It requires pulsed secondary ion generation using either a pulsed primary ion gun or a pulsed secondary ion extraction. It is the only analyzer type able to detect all generated secondary ions simultaneously, and is the standard analyzer for static SIMS instruments.
The magnetic sector mass spectrometer causes a physical separation of ions of a different mass-to-charge ratio. The physical separation of the secondary ions is caused by the Lorentz force when the ions pass through a magnetic field that is perpendicular to the velocity vector of the secondary ions. The Lorentz force states that a particle will experience a force
NanoSIMS can capture the spatial variability of isotopic and elemental measurements of sub-micron areas, grains or inclusions from geological, materials science and biological samples.[13] This instrument can characterise nanostructured materials with complex composition that are increasingly important candidates for energy generation and storage.
NanoSIMS has also proved useful in studying cosmochemical issues, where samples of single, micro- or sub-micrometer-sized grains from meteorites as well as microtome sections prepared by the focused ion beam (FIB) technique can be analyzed. NanoSIMS can be combined with transmission electron microscopy (TEM) when using microtome or FIB sections. This combination allows for correlated mineralogical and isotopic studies in situ at a sub-micrometer scale.
It is particularly useful in materials research because of its high sensitivity at high mass resolution, which allow for trace element imaging and quantification.[14]
Focused ion beam, also known as FIB, is a technique used particularly in the semiconductor industry, materials science and increasingly in the biological field for site-specific analysis, deposition, and ablation of materials. A FIB setup is a scientific instrument that resembles a scanning electron microscope (SEM). However, while the SEM uses a focused beam of electrons to image the sample in the chamber, a FIB setup uses a focused beam of ions instead. FIB can also be incorporated in a system with both electron and ion beam columns, allowing the same feature to be investigated using either of the beams. FIB should not be confused with using a beam of focused ions for direct write lithography (such as in proton beam writing). These are generally quite different systems where the material is modified by other mechanisms.
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information.
