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 magnetic element 添加此单词到默认生词本
磁力元件
磁性元件
磁元件
地磁要素




    Element \El"e*ment\, n. [F. ['e]l['e]ment, L. elementum.]
    1. One of the simplest or essential parts or principles of
    which anything consists, or upon which the constitution or
    fundamental powers of anything are based.

    2. One of the ultimate, undecomposable constituents of any
    kind of matter. Specifically: (Chem.) A substance which
    cannot be decomposed into different kinds of matter by any
    means at present employed; as, the elements of water are
    oxygen and hydrogen.

    Note: The elements are naturally classified in several
    families or groups, as the group of the alkaline
    elements, the halogen group, and the like. They are
    roughly divided into two great classes, the metals, as
    sodium, calcium, etc., which form basic compounds, and
    the nonmetals or metalloids, as oxygen, sulphur,
    chlorine, which form acid compounds; but the
    distinction is only relative, and some, as arsenic,
    tin, aluminium, etc., form both acid and basic
    compounds. The essential fact regarding every element
    is its relative atomic number, which is equal to the
    number of protons in the nucleus, and also equal to the
    number of electrons in orbitals around the nucleus when
    the atom is neutral. When the elements are tabulated in
    the order of their ascending atomic numbers, the
    arrangement constitutes the series of the Periodic law
    of Mendelejeff. See {Periodic law}, under {Periodic}.
    This Periodic law enables us to predict the qualities
    of unknown elements. The number of elements known in
    1890 were about seventy-five, but at that time the gaps
    in the Periodic law indicated the possibility of many
    more. All of the elements up to atomic number 100 have
    now been observed though some are radioactive and very
    unstable, and in some cases cannot be accumulated in
    quantity sufficient to actually see by eye. The
    properties predicted by the periodic law wre close to
    the observed properties in many cases. Additional
    unstable elements of atomic number over 100 are
    observed from time to time, prepared in cyclotrons,
    particle acclerators, or nuclear reactors, and some of
    their properties are measurable by careful observation
    of microscopic quantities, as few as several atoms. For
    such unstable elements, the properties are now
    predicted primarily by calculations based on quantum
    mechanics. Such theories suggest that there may be an
    "island" of relative stability of elements of atomic
    number over 120, but this has yet to be confirmed by
    experiment.
    Many of the elements with which we are familiar, as
    hydrogen, carbon, iron, gold, etc., have been
    recognized, by means of spectrum analysis, in the sun
    and the fixed stars. The chemical elements are now
    known not be simple bodies, but only combinations of
    subatomic particles such as protons, neutrons, and
    electrons; ahd protons and neutrons are now believed to
    be themselves combinations of quarks, particles which
    are not observed singly, but only in combinations.
    In formulas, the elements are designated by
    abbreviations of their names in Latin or New Latin,
    given in the table below. The atomic weights given in
    the table below are the

    {chemical atomic weights}, in some cases being the weighted
    average of the atomic weights of individual isotopes, each
    having a different atomic weight. The atomic weight of the
    individual isotopes are called the physical atomic
    weights. In those few cases where there is only one stable
    isotope of an element, the chemical and physical atomic
    weights are the same. The mass-spectrometric atomic
    weights are those used for careful mass-spectrometric
    measurements. For more details about individual elements,
    see the element names in the vocabulary The Elements
    ----------------------------------------------------------
    Name |Sym-| Atomic Weight |
    |bol | O=16 | H=1 | C=12.000
    ----------------------------------------------------------
    Aluminum | Al | 27.1 | 26.9 |
    Antimony (Stibium) | Sb | 120 | 119.1 |
    Argon | A | 39.9 | 39.6 |
    Arsenic | As | 75 | 74.4 |
    Astatine | At |
    Barium | Ba | 137.4 | 136.4 |
    Beryllium | Be |
    Bismuth | Bi | 208.5 | 206.9 |
    Boron | B | 11 | 10.9 |
    Bromine | Br | 79.96 | 79.36|
    Cadmium | Cd | 112.4 | 111.6 |
    Cesium (Caesium) | Cs | 133 | 132 |
    Calcium | Ca | 40 | 39.7 |
    Carbon | C | 12 | 11.91| 12.000
    Cerium | Ce | 140 | 139 |
    Chlorine | Cl | 35.45 | 35.18|
    Chromium | Cr | 52.1 | 51.7 |
    Cobalt | Co |
    Columbium (see {Beryllium})
    Copper | Cu |
    ({Cuprum})
    Erbium | Er |
    Europium | Eu |
    Einsteinium | Es |
    Fermium | Fe |
    Fluorine | F |
    Gadolinium | Gd |
    Gallium | Ga |
    Germanium | Ge |
    Glucinum (now {Beryllium})
    Gold (Aurum) | Au |
    Helium | He |
    Hydrogen | H |
    Indium | In |
    Iodine | I |
    Iridium | Ir |
    Iron | Fe |
    (Ferrum)
    Krypton | Kr |
    Lanthanum | La |
    Lead | Pb |
    (Plumbum)
    Lithium | Li |
    Magnesium | Mg |
    Manganese | Mn |
    Mercury | Hg |
    ({Hydrargyrum})
    Molybdenum | Mo |
    Neodymium | Nd |
    Neon | Ne |
    Nickel | Ni |
    Niobium | Nb |
    (see Columbium)
    Nitrogen | N |
    Osmium | Os |
    Oxygen | O |
    Palladium | Pd |
    Phosphorus | P |
    Platinum | Pt |
    Potassium | K |
    (Kalium)
    Praseodymium | Pr |
    Rhodium | Rh |
    Rubidium | Rb |
    Ruthenium | Ru |
    Samarium | Sa |
    Scandium | Sc |
    Selenium | Se |
    Silicon | Si |
    Silver | Ag |
    (Argentum)
    Sodium | Na |
    (Natrium)
    Strontium | Sr |
    Sulphur | S |
    Tantalum | Ta |
    Tellurium | Te |
    Thallium | Tl |
    Thorium | Th |
    Thulium | Tu |
    Tin | Sn |
    (Stannum)
    Titanium | Ti |
    Tungsten | W |
    (Wolframium)
    Uranium | U |
    Vanadium | V |
    Wolfranium (see {Tungsten})
    Xenon | X |
    Ytterbium | Yb |
    Yttrium | Y |
    Zinc | Zn |
    Zirconium | Zr |
    ----------------------------------------------------------

    Note: Several other elements have been announced, as holmium,
    vesbium, austrium, etc., but their properties, and in
    some cases their existence, have not yet been
    definitely established.

    3. One of the ultimate parts which are variously combined in
    anything; as, letters are the elements of written
    language; hence, also, a simple portion of that which is
    complex, as a shaft, lever, wheel, or any simple part in a
    machine; one of the essential ingredients of any mixture;
    a constituent part; as, quartz, feldspar, and mica are the
    elements of granite.

    The simplicity which is so large an element in a
    noble nature was laughed to scorn. --Jowett
    (Thucyd.).

    4.
    (a) One out of several parts combined in a system of
    aggregation, when each is of the nature of the whole;
    as, a single cell is an element of the honeycomb.
    (b) (Anat.) One of the smallest natural divisions of the
    organism, as a blood corpuscle, a muscular fiber.

    5. (Biol.) One of the simplest essential parts, more commonly
    called cells, of which animal and vegetable organisms, or
    their tissues and organs, are composed.

    6. (Math.)
    (a) An infinitesimal part of anything of the same nature
    as the entire magnitude considered; as, in a solid an
    element may be the infinitesimal portion between any
    two planes that are separated an indefinitely small
    distance. In the calculus, element is sometimes used
    as synonymous with differential.
    (b) Sometimes a curve, or surface, or volume is considered
    as described by a moving point, or curve, or surface,
    the latter being at any instant called an element of
    the former.
    (c) One of the terms in an algebraic expression.

    7. One of the necessary data or values upon which a system of
    calculations depends, or general conclusions are based;
    as, the elements of a planet's orbit.

    8. pl. The simplest or fundamental principles of any system
    in philosophy, science, or art; rudiments; as, the
    elements of geometry, or of music.

    9. pl. Any outline or sketch, regarded as containing the
    fundamental ideas or features of the thing in question;
    as, the elements of a plan.

    10. One of the simple substances, as supposed by the ancient
    philosophers; one of the imaginary principles of matter.
    (a) The four elements were, air, earth, water, and fire;

    Note: whence it is said, water is the proper element of
    fishes; air is the element of birds. Hence, the state
    or sphere natural to anything or suited for its
    existence.

    Of elements
    The grosser feeds the purer: Earth the Sea;
    Earth and the Sea feed Air; the Air those Fires
    Ethereal. --Milton.

    Does not our life consist of the four elements?
    --Shak.

    And the complexion of the element [i. e.,the sky
    or air]
    In favor's like the work we have in hand,
    Most bloody, fiery, and most terrible. --Shak.

    About twelve ounces [of food], with mere element
    for drink. --Cheyne.

    They show that they are out of their element.
    --T. Baker.
    Esp., the conditions and movements of the air. ``The
    elements be kind to thee.''
    (b) The elements of the alchemists were salt, sulphur,
    and mercury. --Brande & C.

    11. pl. The whole material composing the world.

    The elements shall melt with fervent heat. --2
    Peter iii. 10.

    12. pl. (Eccl.) The bread and wine used in the eucharist or
    Lord's supper.

    {Magnetic element}, one of the hypothetical elementary
    portions of which a magnet is regarded as made up.

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