Properties of Several Nuclei

Frequency Natural Sensitivity Magnetic Spin Quadrupole Magnetogyric 

MHz for a Abundance at Constant Moment Number Moment Ratio y 

Source Varian Associates NMR Table, 4th ed., 1%4, with permission. 

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The Mossbauer effect is the emission and resonant absorption of nuclear y-rays studied under conditions such that the nuclei have negligible recoil velocities when y-rays are emitted or absorbed. This is only achieved by working with solid samples in which the nuclei are held rigidly in a crystal lattice. The energy, and thus the frequency of the y-radiation involved, corresponds to the transition between the ground state and the short-lived excited state of the nuclide concerned. Table 2.4 lists properties of several nuclei which can be observed using Mdssbauer spectroscopy. 

Relevant properties, including the spin number, 7, of several nuclei are given in Chapter 6, Appendix A. The spin number 7 can be determined from the atomic mass and the atomic number as shown in Table 3.1. 

Although the DNA-binding properties of several procaryotic topoisomerases have been well characterized, little information is currently available concerning eucaryotic enzymes. Some eucaryotic topoisomerases may be intimately associated with other nuclear proteins HeLa topoisomerases I and II have been found to be associated with chromatin (Javaherian and Liu, 1983 Liu et al., 1983b). HeLa topoisomerase I has been shown to bind to the nonhistone protein HMG17, which also stimulates DNA catenation by the enzyme (Javaherian and Liu, 1983 Tse et al., 1984). It has been suggested that type II topoisomerase is an important component of the chromosomal scaffold in interphase nuclei and mitotic chromosomes from chicken cell lines (Earnshaw et al., 1985). In addition, an ATP-dependent topoisomerase has been found associated with several other enzymes of DNA metabolism in a complex (termed the replitase complex) isolated from the nuclei of Chinese hamster embryo fibroblast cells (Noguchi et al., 1983). 

Decay properties of transuranium nuclides lead to the understanding of proton excess heavy nuclei verification of the proton drip line, nuclear structure of large deformed nuclei such as octupole and hexadecapole deformation, and fission barrier heights. There are several textbooks and review articles on nuclear decay properties of transuranium nuclei (e.g., Hyde et al. 1964 Seaborg and Loveland 1985 Poenaru 1996). Theoretical nuclear models of heavy nuclei are presented by Rasmussen (1975) and the nuclear structure with a deformed single-particle model is discussed by Chasman et al. (1977). Radioactive decay properties of transuranium nuclei are tabulated in the Table of Isotopes (Firestone and Shirley 1996). Recent nuclear and decay properties of nuclei in their ground and isomeric states are compiled and evaluated by Audi et al. (1997), while the calculated atomic mass excess and nuclear ground-state deformations are tabulated by MoUer et al. (1995). 

Nowadays MAS measurements are the standard experiments which are routinely used in the majority of Solid State NMR. CP-MAS, the combination of MAS and CP experiments has been routinely utilized to obtain high-resolution NMR spectra of dilute spins such as N, and P Nuclei in solid materials.CP-MAS plays a key role in the characterization of homogeneous catalysts immobilized on solid supports, providing direct information about the structure of support and the metal complex. Accordingly a number of NMR studies were performed in order to investigate the morphology and chemical properties of several types of pure and functionalized silica materials (ref. 52 and references therein). ... 

The development of particle accelerators grew out of the discovery of radioactivity in uranium by Henri Becquerel in Paris in 1896. Some years later, due to the work of Ernest Rutherford and others, it was found that the radioactivity discovered by Becquerel was the emission o particles with kinetic energies o several MeV from uranium nuclei. Research using the emitted particles began shortly thereafter. It was soon realized that if scientists were to learn more about the properties of subatomic particles, they had to be accelerated to energies greater than those attained in natural radioactivity. 

Investigation of physical and chemical properties of recently synthesized, relatively long-living isotopes of superheavy elements (SHEs) with nuclear charges Z=105 to 116 [1, 2, 3, 4] and their compounds is of fundamental importance. Their measured lifetimes may reach several hours and the nuclei near the top of the island of stability are predicted to exist for many years. The experimental study of the SHE properties is very difficult be-... 

A crucial feature of PNC experiments in atoms, molecules, liquids or solids is that for interpretation of measured data in terms of fundamental constants of the P,T-odd interactions, one must calculate those properties of the systems, which establish a connection between the measured data and studied fundamental constants (see section 4). These properties are described by operators heavily concentrated near or on heavy nuclei they cannot be measured and their theoretical study is not a trivial task. During the last several years the significance of (and requirement for) ab initio calculation of electronic structure providing a high level of reliability and accuracy in accounting for both relativistic and correlation effects has only increased (see sections 3 and 10). 

There are several hundred radionuclides that have been used as radiotracers. A partial list of the properties of these nuclides and their production methods are shown in Table 4.1. The three common production mechanisms for the primary radionuclides are (n,y) or (n,p) or (n,a) reactions in a nuclear reactor (R), charged-particle-induced reactions usually involving the use of a cyclotron (C), and fission product nuclei (F), typically obtained by chemical separation from irradiated uranium. The neutron-rich nuclei are generally made using reactors or... 

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