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secondary and electrons
The lost energy is converted into alternative forms such as heat, emission of low-energy secondary electrons and high-energy backscattered electrons, light emission ( cathodoluminescence ) or X-ray emission, which provide signals carrying information about the properties of the specimen surface, such as its topography and composition.
In the reflection electron microscope ( REM ) as in the TEM, an electron beam is incident on a surface, but instead of using the transmission ( TEM ) or secondary electrons ( SEM ), the reflected beam of elastically scattered electrons is detected.
It will also create secondary Hall currents, and accelerate magnetospheric particles — electrons in the arcs of the polar aurora, and singly ionized oxygen ions ( O +) which contribute to the ring current.
By means of a series of electrodes ( dynodes ) at ever-higher potentials, these electrons are accelerated and substantially increased in number through secondary emission to provide a readily detectable output current.
Intensification of the signal is achieved either through acceleration of the electrons or by increasing the number of electrons through secondary emissions, such as with a Micro-channel plate.
The electrons interact with electrons in the sample, producing secondary electrons, back-scattered electrons, and characteristic X-rays that can be detected and that contain information about the sample's surface topography and composition.
The types of signals produced by a SEM include secondary electrons, back-scattered electrons ( BSE ), characteristic X-rays, light ( cathodoluminescence ), specimen current and transmitted electrons.
The energy exchange between the electron beam and the sample results in the reflection of high-energy electrons by elastic scattering, emission of secondary electrons by inelastic scattering and the emission of electromagnetic radiation, each of which can be detected by specialized detectors.
Operating conditions to prevent charging of non-conductive specimens must be adjusted such that the incoming beam current was equal to sum of outcoming secondary and backscattered electrons currents.
The most common imaging mode collects low-energy (< 50 eV ) secondary electrons that are ejected from the k-orbitals of the specimen atoms by inelastic scattering interactions with beam electrons.
The brightness of the signal depends on the number of secondary electrons reaching the detector.

secondary and are
Ideally speaking, it should be allowed to operate only where the public has a great stake in the continuity of supply or services, and where the actions of a single proprietor are secondary to the needs of society.
Other conceivable goals, such as character-education and social adjustment, are of secondary importance to them.
On the remainder of the clear channels, the dominant ( class 1 ) -- B stations are protected as described above, and the relatively small number of secondary ( class 2 ) ) stations permitted to operate on these channels at night are required to operate directionally and/or with reduced power so as to protect the class 1, stations.
The coordination complexes formed by transition metals with primary and secondary phosphines and arsines are being investigated ( R. G. Hayter ).
In a process called ' anomalous secondary growth ', they are able to create new vascular bundles around which thickening growth occurs.
The stamens are usually found around the style, either aggregated densely or fused into a tube, probably an adaptation in association with the plunger ( brush ; or secondary ) pollination that is common among the families of the order, wherein pollen is collected and stored on the length of the pistil.
An abugida ( from Ge ‘ ez አቡጊዳ ’ äbugida ), also called an alphasyllabary, is a segmental writing system in which consonant – vowel sequences are written as a unit: each unit is based on a consonant letter, and vowel notation is secondary.
The parish's main Gaelic football pitch and two secondary schools are on the mainland at Poll Raithní.
The secondary constituents are often called solutes.
The usual symptoms are cough and sputum production, and secondary infections can occur.
Amides are also commonly derived from secondary amines ( R ' RNH ) with the formula RC ( O ) NR ' R.
Alkaloids are produced by a large variety of organisms, including bacteria, fungi, plants, and animals, and are part of the group of natural products ( also called secondary metabolites ).
4, 181 people are employed in the secondary sector and there are 164 businesses in this sector.
Of the school age population (), there are 861 students attending primary school, there are 280 students attending secondary school, there are 455 students attending tertiary or university level schooling, there are 35 students who are seeking a job after school in the municipality.
The color range is limited to common primary and secondary colors, and the actual pigments are unspecified.
Rules can range from the very simple, as in tic-tac-toe, to those describing a game universe in great detail, as in Dungeons & Dragons ( although most of the latter are role-playing games where the board is secondary to the game, helping to visualize the game scenario ).
) Base stacking effects are especially important in the secondary structure and tertiary structure of RNA ; for example, RNA stem-loop structures are stabilized by base stacking in the loop region.

secondary and first
Aphrodite figures as a secondary character in the Tale of Eros and Psyche, which first appeared as a digressive story told by an old woman in Lucius Apuleius ' novel, The Golden Ass, written in the second century AD.
The Attlee Government ensured provisions of the Education Act 1944 were fully implemented, with free secondary education becoming a right for the first time.
The publication of the first six volumes of the Collected Papers ( 1931 – 35 ), the most important event to date in Peirce studies and one that Cohen made possible by raising the needed funds, did not prompt an outpouring of secondary studies.
In countries such as Kenya-particularly in Nairobi and other cities where there is an expanding middle class-English is increasingly being used in the home as the first language, albeit with significant lexical influence from and secondary use of Swahili in a context of code-switching.
Swallowing difficulties ( secondary achalasia ) may be the first symptom of digestive disturbances and may lead to malnutrition.
The second, 21164 or EV5, was the first microprocessor to place a large secondary cache on chip.
The Elements begins with plane geometry, still taught in secondary school as the first axiomatic system and the first examples of formal proof.
The lead acid battery was the first practical secondary ( rechargeable ) battery that could have its capacity replenished from an external source.
The first exoplanet found to be orbiting such a star could then be regarded as a secondary sub-component that should be given the suffix " Ab.
In 1872 the first secondary school was built. On 3 December 1877 Grenada's old representative system of government was replaced by the pure Crown Colony model.
The first assumption means that the secondary waves oscillate at a quarter of a cycle out of phase with respect to the primary wave, and that the magnitude of the secondary waves are in a ratio of 1: λ to the primary wave.
Educated first at home, then spending four years of secondary school in Bienne, he completed his elementary studies in Lausanne.
Given two secondary stations, the time difference ( TD ) between the primary and first secondary identifies one curve, and the time difference between the primary and second secondary identifies another curve, the intersections of which will determine a geographic point in relation to the position of the three stations.
It is thus named for being both the one written authority ( codex ) secondary ( only ) to the Tanakh as a basis for the passing of judgment, a source and a tool for creating laws, and the first of many books to complement the Bible in certain aspects.
The regular constructor is called the first time the state for the shared class is initialized through a subclass constructor, and the secondary constructor will be invoked for all other subclasses.
Media studies in Australia was first developed as an area of study in Victorian universities in the early 1960s, and in secondary schools in the mid 1960s.
In secondary schools, an early " film studies " course first began being taught as part of the Victorian junior secondary curriculum during the mid 1960s.
Notable figures in the development of the Victorian secondary school curriculum were the media artist and director Peter Greenaway, Trevor Barr ( who authored one of the first media text books Reflections of Reality ) and later John Murray ( who authored The Box in the Corner, In Focus, and 10 Lessons in Film Appreciation ).
A Killing field was an area between the main wall and a secondary wall, so when the first wall was breached the attackers would run into the killing field to be confronted by another wall from which soldiers bombarded them.
Linus Pauling is credited with the successful prediction of regular protein secondary structures based on hydrogen bonding, an idea first put forth by William Astbury in 1933.

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