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271.
Wolfgang QuappVladlen Melnikov Georg Ch. Mellau 《Journal of Molecular Spectroscopy》2002,211(2):189-197
High-resolution measurements have been made on the infrared emission spectrum of the doubly substituted HCN isotopomer, H13C15N, at temperatures on the order of 1370 K. The measurements cover the region 400-850 cm−1 with a resolution (1/MOPD) of 0.006 cm−1. We could assign hot bands with upper levels up to the 0 1111 0 state. The assignments have been verified for states up to v2=5 by fitting with earlier room temperature absorption measurements of overtone and hot bands. All the measurements for H13C15N have been combined in a single least-squares fit that includes approximately 8670 rovibrational lines which have a root-mean-square deviation on the order of 0.000 33 cm−1. The spectroscopic constants for the bending states v2=1,…,11 are reported, as well as those for some combination states involving the two stretching modes. 相似文献
272.
Comment on "Indispensable finite time corrections for Fokker-Planck equations from time series data"
Friedrich R Renner Ch Siefert M Peinke J 《Physical review letters》2002,89(14):149401; author reply 149402
273.
We demonstrate that secure quantum key distribution systems based on continuous variable implementations can operate beyond the apparent 3 dB loss limit that is implied by the beam splitting attack. The loss limit was established for standard minimum uncertainty states such as coherent states. We show that, by an appropriate postselection mechanism, we can enter a region where Eve's knowledge on Alice's key falls behind the information shared between Alice and Bob, even in the presence of substantial losses. 相似文献
274.
We have evidenced by small-angle neutron scattering at low temperature the coexistence of ferromagnetism (F) and antiferromagnetism (AF) in Pr0.67Ca0.33MnO3. The results are compared to those obtained in Pr0.80Ca0.20MnO3 and Pr0.63Ca0.37MnO3, which are F and AF, respectively. Quantitative analysis shows that the small-angle scattering is not due to a mesoscopic mixing but to a nanoscopic electronic and magnetic "red cabbage" structure, in which the ferromagnetic phase exists in the form of thin layers in the AF matrix (stripes or 2D "sheets"). 相似文献
275.
We investigate correlated electronic transport in single-walled carbon nanotubes with two intramolecular tunneling barriers. We suggest that below a characteristic temperature the long-range nature of the Coulomb interaction becomes crucial to determine the temperature dependence of the maximum G(max) of the conductance peak. Correlated sequential tunneling dominates transport yielding the power law G(max) proportional, variant T(alpha(end-end)-1), typical for tunneling between the ends of two Luttinger liquids. Our predictions are in agreement with recent measurements. 相似文献
276.
Chen X Sichelschmidt O Kleemann W Petracic O Binek Ch Sousa JB Cardoso S Freitas PP 《Physical review letters》2002,89(13):137203
The ac susceptibility of a superferromagnetic discontinuous multilayer [Co(80)Fe20(1.4 nm)/Al(2)O3(3 nm)](10) is measured as a function of temperature, frequency, and field amplitude and compared to static and dynamic hysteresis loops. Its properties are successfully mapped onto the predicted [T. Nattermann, V. Pokrovsky, and V. M. Vinokur, Phys. Rev. Lett. 87, 197005 (2001)]] dynamical phase transitions, which link the relaxation, creep, sliding, and switching regimes of pinned domain walls. 相似文献
277.
The proposed universality of small scale turbulence is investigated for a set of measurements in a cryogenic free jet with a variation of the Reynolds number (Re) from 8500 to 10(6) (max(R(lambda) approximately 1200). The traditional analysis of the statistics of velocity increments by means of structure functions or probability density functions is replaced by a new method which is based on the theory of Markov processes. It gives access to a more complete characterization by means of joint probabilities of finding velocity increments at several scales. Based on this more comprehensive method, our results are very far from a possible universal state, even for R(lambda) above 1000. 相似文献
278.
Syringolide 2, an elicitor of the bacterial plant pathogen Pseudomonas syringae pv. tomato which triggers a hypersensitive defense response in resistant soybean plants, has been synthesized in five steps via a fructose 1,6-diphosphate aldolase reaction. 相似文献
279.
Marina S. Fonari Yurii A. Simonov Victor Ch. Kravtsov Janusz Lipkowski Gabriele Bocelli Edward V. Ganin Vladimir O. Gelmboldt 《Journal of chemical crystallography》1999,29(12):1245-1254
Synthesis and single-crystal X-ray structures are recorded for three adducts of SbF3 with different azacrown ethers. [SbF3·H2O·L1], 1, (L1 = 12,13-benz-1,10-di(azamethyl)-4,7-dioxacyclotetradecane-1,14-dione), triclinic,
, a = 11.234(2), b = 11.691(2), c = 8.869(2) Å, = 94.66(3), = 113.12(3), = 67.82(3)°, Z = 2. [SbF3Cl·H2O·(HL2)], 2, (L2 = monoaza-18-crown-6), orthorhombic, P212121, a = 8.763(2), b = 13.003(3), a = 16.836(3) Å, Z = 4. [(SbF3)2Cl2·(H2L3)], 3, (L3 = 1,10-diaza-18-crown-6), triclinic,
, a = 8.284(2), b = 9.016(2), c = 9.134(2) Å, = 82.92(3), = 65.24(3), = 63.38(3)°, Z = 1. All three structures include SbF3 neutral molecules in the pyramidal mode and the antimony second coordination sphere is completed up to six in different fashions. In 1 the dimeric (SbF3)2 adducts are made up due to the involvement of the symmetry-related fluorine atom in coordination. The distorted octahedron is then completed by water molecule and carbonyl oxygen of L1. The neutral molecules are joined by coordination and hydrogen bonds in the infinite ribbons. 2 and 3 are both comprised of neutral and charged species also bounded via coordination and hydrogen bonds. L2 and L3 in the complexes adopt the form of single and double-charged cations, respectively. The inorganic backbone unites the neutral SbF3 molecules and chloride anions in the alternative mode. The sixth coordination site in the antimony polyhedron is completed by the water molecule in 2 and the ethereal oxygen atom in 3. Alignment of the inorganic entities within the structures of 2 and 3 is strikingly similar. Hydrogen bonding patterns are discussed. 相似文献
280.
A. Petri Ch. Br uchle H. Leigeber A. Miller H. -P. Weitzel F. -H. Kreuzer 《Liquid crystals》1993,15(1):113-121
Photosensitive cholesteric polysiloxanes, which contain an azo dye, were irradiated with linearly polarized light. The cholesteric samples were oriented in the Grandjean texture. Before irradiation they reflected circularly polarized light in the near infrared region. For perpendicular incidence, only one order of reflection was observed. Upon irradiation with linearly polarized light, which is absorbed by the azo dye, additional reflection bands appeared in the visible part of the spectrum. It turned out that the additional reflection is caused by a new Bragg type grating which shows higher reflection orders. The formation of the grating is based on the periodic deformation of the helical ordering of the molecules. The deformation is periodic, as due to photoselection, only dye molecules in equidistant layers with a suitable orientation absorb radiation. For low exposure, the grating reflects linearly polarized light. After continued irradiation, the reflection bands disappear almost completely. High birefringence, strongly dichroic dye absorption and the loss of the reflecting properties prove that a planar nematic texture has developed. The formation of this texture from the Grandjean texture is a new example for photoinduced rotational diffusion. 相似文献