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Hydrogen radioactive isotopes

Also present in the first test tube is a synthetic analog of ATP in which both the 2 and 3 hydroxyl groups have been replaced by hydrogens This compound is called 2 3 dideoxyadenosme triphosphate (ddATP) Similarly ddTTP is added to the second tube ddGTP to the third and ddCTP to the fourth Each tube also contains a primer The primer is a short section of the complementary DNA strand which has been labeled with a radioactive isotope of phosphorus ( P) When the electrophoresis gel is examined at the end of the experiment the positions of the DNAs formed by chain extension of the primer are located by a technique called autoradiography which detects the particles emitted by the P isotope... [Pg.1181]

A few natural isotopes are radioactive. Of the three isotopes of hydrogen, only that of mass 3 (tritium) i.s radioactive. Radioactive isotopes can be examined by other instrumental means than mass spectrometry, but these other means cannot see the nonradioactive isotopes and are not as versatile as a mass Spectrometer. [Pg.423]

Many artificial (likely radioactive) isotopes can be created through nuclear reactions. Radioactive isotopes of iodine are used in medicine, while isotopes of plutonium are used in making atomic bombs. In many analytical applications, the ratio of occurrence of the isotopes is important. For example, it may be important to know the exact ratio of the abundances (relative amounts) of the isotopes 1, 2, and 3 in hydrogen. Such knowledge can be obtained through a mass spectrometric measurement of the isotope abundance ratio. [Pg.423]

More than 1500 radioactive isotopes have been prepared in the laboratory. The number of such isotopes per element ranges from 1 (hydrogen and boron) to 34 (indium). They are all prepared by bombardment reactions in which a stable nucleus is converted to one... [Pg.514]

Until the advent of modem physical methods for surface studies and computer control of experiments, our knowledge of electrode processes was derived mostly from electrochemical measurements (Chapter 12). By clever use of these measurements, together with electrocapillary studies, it was possible to derive considerable information on processes in the inner Helmholtz plane. Other important tools were the use of radioactive isotopes to study adsorption processes and the derivation of mechanisms for hydrogen evolution from isotope separation factors. Early on, extensive use was made of optical microscopy and X-ray diffraction (XRD) in the study of electrocrystallization of metals. In the past 30 years enormous progress has been made in the development and application of new physical methods for study of electrode processes at the molecular and atomic level. [Pg.468]

Even nowadays the application of radioactive isotopes is the most sensitive method for the analysis of biomolecules or their reaction products. Besides the low detection limits, the replacement of a naturally overbalancing stable isotope by its radioactive analogue does not interfere with the physical or chemical properties of the enzyme (with some exceptions for hydrogens). Figure 6 lists some frequently used radioactive isotopes and their half-life periods. [Pg.76]

Hydrogen The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight 1. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are protons. Besides the common HI isotope, hydrogen exists as the stable isotope deuterium and the unstable, radioactive isotope tritium. [NIH]... [Pg.68]

Examples of isotopes are abundant. The major form of hydrogen is represented as H (or H-1), with one proton H, known as the isotope deuterium or heavy hydrogen, consists of one proton and one neutron (thus an amu of 2) and is the isotope of hydrogen called tritium with an amu of 3. Carbon-12 ( C or C-12) is the most abundant form of carbon, though carbon has several isotopes. One is the C isotope, a radioactive isotope of carbon that is used as a tracer and to determine dates of organic artifacts. Uranium-238 is the radioactive isotope (Note The atomic number is placed as a subscript prefix to the element s symbol—for example, —and the atomic mass number can be written either as a dash and number fol-... [Pg.31]

Hydrogen has two stable isotopes, H (0.99985) and (0.00015), and a short-hved radioactive isotope iH (tritium) produced in the atmosphere by interaction of with cosmic ray neutrons ... [Pg.779]

Until 1931 it was assumed that hydrogen consisted of only one isotope. Urey et al. (1932) detected the presence of a second stable isotope, which was called deuterium. (In addition to these two stable isotopes there is a third naturally oc-curing but radioactive isotope, H, tritium, with a half-life of approximately 12.5 years). Rosman and Taylor (1998) gave the following average abundances of the stable hydrogen isotopes ... [Pg.36]

An isotope of hydrogen a stable, non-radioactive isotope atomic number 1 atomic mass 2.014 molecular weight (for the diatomic heavy hydrogen molecule) 4.028. [Pg.287]

If a fusion reaction produces no appreciable radioactive isotopes, why does a hydrogen bomb produce significant radioactive fallout ... [Pg.138]

TRITIUM. The radioactive isotope of hydrogen, with a mass number 3, is termed tntnim. it is one form of heavy hydrogen, the other form being deuterium. See also Nuclear Power Technology. [Pg.1631]

All hydrogen atoms have 1 proton in their nucleus (otherwise they wouldn t be hydrogen), but most (99.985%) have no neutrons. These hydrogen atoms, called protium, have mass number 1. In addition, 0.015% of hydrogen atoms, called deuterium, have 1 neutron and mass number 2. Still other hydrogen atoms, called tritium, have 2 neutrons and mass number 3. An unstable, radioactive isotope, tritium occurs only in trace amounts on Earth but is made artificially in nuclear reactors. As other examples, there are 13 known isotopes of carbon, only 2 of which occur commonly, and 25 known isotopes of uranium, only 3 of which occur commonly. [Pg.46]


See other pages where Hydrogen radioactive isotopes is mentioned: [Pg.150]    [Pg.145]    [Pg.499]    [Pg.310]    [Pg.118]    [Pg.435]    [Pg.282]    [Pg.39]    [Pg.292]    [Pg.161]    [Pg.272]    [Pg.100]    [Pg.38]    [Pg.285]    [Pg.391]    [Pg.449]    [Pg.389]    [Pg.150]    [Pg.329]    [Pg.319]    [Pg.695]    [Pg.941]    [Pg.950]    [Pg.1071]    [Pg.1082]    [Pg.1188]    [Pg.1037]    [Pg.267]    [Pg.110]    [Pg.432]    [Pg.643]    [Pg.181]   
See also in sourсe #XX -- [ Pg.341 ]




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Isotopic radioactive

Radioactive hydrogen

Radioactivity isotopes

The Radioactive Heavy Hydrogen Isotope

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