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Through space

Dipolar D / 10 -10 Through space spin-spin interaction, axially symmetric traceless tensor... [Pg.1467]

Independent molecules and atoms interact through non-bonded forces, which also play an important role in determining the structure of individual molecular species. The non-bonded interactions do not depend upon a specific bonding relationship between atoms, they are through-space interactions and are usually modelled as a function of some inverse power of the distance. The non-bonded terms in a force field are usually considered in two groups, one comprising electrostatic interactions and the other van der Waals interactions. [Pg.199]

When considering how the evolution of life could have come about, the seeding of terrestrial life by extraterrestrial bacterial spores traveling through space (panspermia) deserves mention. Much is said about the possibility of some form of life on other planets, including Mars or more distant celestial bodies. Is it possible for some remnants of bacterial life, enclosed in a protective coat of rock dust, to have traveled enormous distances, staying dormant at the extremely low temperature of space and even surviving deadly radiation The spore may be neither alive nor completely dead, and even after billions of years it could have an infinitesimal chance to reach a planet where liquid water could restart its life. Is this science fiction or a real possibility We don t know. Around the turn of the twentieth century Svante Arrhenius (Nobel Prize in chemistry 1903) developed this theory in more detail. There was much recent excitement about claimed fossil bacterial remains in a Martian meteorite recovered from Antarctica (not since... [Pg.16]

The effect of an o>-phenyl group as a function of the alkyl chain length has been studied in 3-(through-space interaction has been evidenced on the reactivity of the thiocarbonyl group. [Pg.392]

Another technique often used to examine the stmcture of double-heUcal oligonucleotides is two-dimensional nmr spectroscopy (see AfAGNETiC SPIN resonance). This method rehes on measurement of the nuclear Overhauser effects (NOEs) through space to determine the distances between protons (6). The stmcture of an oligonucleotide may be determined theoretically from a set of iaterproton distances. As a result of the complexities of the experiment and data analysis, the quality of the stmctural information obtained is debated. However, nmr spectroscopy does provide information pertaining to the stmcture of DNA ia solution and can serve as a complement to the stmctural information provided by crystallographic analysis. [Pg.250]

Nuclear Overhauser enhancement (NOE) spectroscopy has been used to measure the through-space interaction between protons at and the protons associated with the substituents at N (20). The method is also useful for distinguishing between isomers with different groups at and C. Reference 21 contains the chemical shifts and coupling constants of a considerable number of pyrazoles with substituents at N and C. NOE difference spectroscopy ( H) has been employed to differentiate between the two regioisomers [153076 5-0] (14) and [153076 6-1] (15) (22). N-nmr spectroscopy also has some utility in the field of pyrazoles and derivatives. [Pg.308]

Radiation is the transfer of heat from one body to another, not in contac t with it, by means of wave motion through space. [Pg.554]

Particle velocity The velocity associated with a point attached to the material as it flows through space. [Pg.41]

The second component is called afield effect and is attributed to through-space interactions of the electric dipoles resulting from polar bonds. [Pg.19]

Suppose particle A moves through space with average speed v A will collide with a B particle if their center-to-center distance is less than or equal to ta -t- rg. Thus, particle A sweeps out an area irlrA + rB) v in which it can collide with B, and the corresponding volume swept out per second is irfrA -t- rg fv. If the concentration of B is B molecules cm , the number of collisions of B particles by this single A particle, per second, is 7r(rA -t- rgfngv. However, the volume also... [Pg.188]

The utility of the Zincke reaction has been extended to the preparation of various NAD and NADH analogs. Holy and co-workers synthesized a series of NAD analogs containing nucleotide bases as a means to study through-space interaction between the pyridinium and base portions. Nicotinamide-derived Zincke salt 8 was used to link with various adenine derivatives via tethers that contained hydroxyl (105 —> 106, Scheme 8.4.35), phosphonate (107—>108, Scheme 8.4.36), and carboxylate "... [Pg.370]


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See also in sourсe #XX -- [ Pg.60 ]

See also in sourсe #XX -- [ Pg.560 , Pg.570 ]

See also in sourсe #XX -- [ Pg.2 , Pg.827 ]




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Asymmetric induction through space

Atoms: atomic number through space, 74-75 stability

Boundaries Through Space

Chemical through-space contribution

Conduction Through the Insulation Space

Correlation through space

Couplings over More than Three Bonds and Through Space

Electron interactions through space

Electron transfer pathways, through space

Electron transfer through-space

Electron tunneling through the space charge layer

Electronic coupling through-space interactions

Electronic direct “through-space

Forster through-space

Interference, through-space

Jumps through space

Long range and through space

Long range and through space reactions

Long-range and through space coupling

Matrix through-space

Moving Freely Through Space

Norbornadiene, through-space interactions

Orbital interactions, through space

Proximate moieties, through-space

Proximity through space

Quantum tunneling through-space

Random search through conformational space

Spin-orbit coupling through-space

Strain through-space term

The NOE Through-Space Interactions between Protons

The through-space vector model

Through-space Scalar Coupling

Through-space acceleration

Through-space antiferromagnetic interaction

Through-space asymmetric polymerization

Through-space bond components

Through-space conjugation

Through-space contact

Through-space contributions

Through-space coupling

Through-space distance dependence

Through-space effects

Through-space electronic interactions

Through-space energy transfer

Through-space interaction

Through-space interaction, characteristics

Through-space mechanisms

Through-space nuclear overhauser effect

Through-space pathway

Through-space polarization

Through-space spin coupling

Through-space stabilizing electronic effect

Through-space term

Through-space transmission between

Through-space tunneling

Through-space vector model

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