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101.
Burkhard Wald 《manuscripta mathematica》1983,42(2-3):297-309
P(I) denotes the abelian group of integer-valuated functions defined on the set I, Pκ (I) its subgroup consisting of all elements, which support has size less than the infinite cardinal κ and Qκ (I) the quotient P(I)/Pκ(I). We formulate a statement I(κ) in the following way: For an arbitrary set I you can lift every homomorphism from P (?) to Qκ(I) to a homomorphism from P(?) to P(I). Using Martin's Axiom we show, that L(?) is independent of ZFC. 相似文献
102.
Ronald D Brown Peter D Godfrey Burkhard Kleibömer 《Journal of Molecular Spectroscopy》1985,114(2):257-273
An extensive study of the microwave spectrum of cyanamide has been undertaken, the analysis being based in part on semirigidbender calculations by the methods of Bunker and Szalay. Inversion lines of NH2CN, branches and a number of vibrational satellites of the J = 2?1 transition were observed. A two-vibrational-state Hamiltonian was used to fit simultaneously the 0+ and 0? microwave data and yielded rotational constants X, Y, Z, DJ, DJK, d1, HJK as well as the inversion splitting and the μyz-connecting matrix element. Vibrational satellite data of seven isotopic species and infrared frequencies of NH2CN were included in the semirigid bender calculations: The NCN spine is nonlinear by ca. 5° in the equilibrium structure of the molecule. Also, ; <HNH/2 = 60.39° ? 0.1134?2; (? is the inversion angle in rad); fixed. The inclusion of the NC bond flexing was necessary in order to reproduce the observed vibrational satellite patterns of NH2CN, NHDCN, and ND2CN. The barrier to inversion of the amino group is 510 ± 6 cm?1 with minima at ±45.0 ±0.2°. The inversion dipole moment is 0.91 ± 0.02 Debye. 相似文献
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Anthropometric manikin for acoustic research. 总被引:1,自引:0,他引:1
105.
Crown ether amino acids (CEAAs) with a luminescent phthalic ester or phthalimide moiety have been prepared. Simple peptide chemistry covalently tethers the macrocycles to give ditopic ammonium-ion binders. The binding events of both crown ether groups are monitored independently by changes of their specific emission properties. The affinity of the bis-CEAA to bis-ammonium ions is distance dependent, which allows distinguishing between isomeric small peptides containing a lysine residue in different positions. 相似文献
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