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21.
Summary The rotational spectra of ONF in the (100), (010) and (001) excited vibrational states were observed and the corresponding vibrationratation α constants determined. A centrifugal-distortion analysis of 156 ground-state rotational transitions yielded accurate values of all the sextic centrifugal-distortion constants. Both vibration-rotation α constants and sextic centrifugal-distortion constants were used to determine, by least-squares methods, the cubic part of the general valence force field of nitrosyl fluoride. Anab initio calculation provided reliable constraints for the three cubic terms of the potential-energy function which are not directly determinable by the available experimental data. Supporting organizations: C.N.R. and M.P.I.  相似文献   
22.
The combination of microwave measurements of the Stark effect in the (001) excited vibrational state with fourteen laser Stark transitions of the hot band (101) ← (001), previously reported in the literature, yielded the values of the dipole moment of ONF both in the (001) and (101) states.  相似文献   
23.
Let M be a two dimensional complex manifold, p ∈ M and a germ of holomorphic foliation of M at p. Let be a germ of an irreducible, possibly singular, curve at p in M which is a separatrix for . We prove that if the Camacho-Sad-Suwa index Ind then there exists another separatrix for at p. A similar result is proved for the existence of parabolic curves for germs of holomorphic diffeomorphisms near a curve of fixed points.  相似文献   
24.
In order to develop new electronic devices, it is necessary to find innovative solutions to the eco‐sustainability problem of materials as substrates for circuits. We realized a photoresponsive device consisting of a semiconducting polymer film deposited onto optically semitransparent and conductive biodegradable poly(3‐hydroxybutyrate) (PHB)/carbon nanotube (CNT) substrates. The experiments indicated that the PHB‐CNT bionanocomposite substrate behaves as an optical window trapping electric charges produced by the photoexcitation of the semiconducting polymer. Such PHB‐CNT functional substrates are expected to be attractive for eco‐friendly electronics. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 596–602  相似文献   
25.
Surface relaxation processes of liquid solutions, under not-far-from-equilibrium conditions, are interpreted from a phenomenological point of view by application of the theory of distributed systems. In the case of diffusion-controlled adsorption, exact analytical expressions describe the transient responses of bulk concentration and dynamic surface tension, consequent to trapezoidal pulses of relative surface area. The mathematical treatment shows that surface responses have a definite physical significance, as they manifest a constitutive property of the system, i.e. the surface dilational modulus.  相似文献   
26.
We explore the capability of spin-1/2 chains to act as quantum channels for both teleportation and transfer of qubits. Exploiting the emergence of long-distance entanglement in low-dimensional systems [Phys. Rev. Lett. 96, 247206 (2006)10.1103/Phys.Rev.Lett.96, 247206(2006)], here we show how to obtain high communication fidelities between distant parties. An investigation of protocols of teleportation and state transfer is presented, in the realistic situation where temperature is included. Basing our setup on antiferromagnetic rotationally invariant systems, both protocols are represented by pure depolarizing channels. We propose a scheme where channel fidelity close to 1 can be achieved on very long chains at moderately small temperature.  相似文献   
27.
We consider the zero-temperature dynamics for the infinite-range, non translation invariant one-dimensional spin model introduced by Marinari, Parisi and Ritort to generate glassy behaviour out of a deterministic interaction. It is argued that there can be a large number of metastable (i.e., one-flip stable) states with very small overlap with the ground state but very close in energy to it, and that their total number increases exponentially with the size of the system.  相似文献   
28.
The microwave spectrum of 2,3-dihydrofuran has been reinvestigated and measurements for the ground and first five excited states of the ring puckering vibration have been extended to higher frequencies and rotational quantum numbers in order to study the vibrational dependence of the rotational and centrifugal distortion constants. The ring puckering potential function derived by Green from the far infrared spectrum does not reproduce the vibrational dependence of the rotational constants well. A slightly different potential function is derived which gives a reasonable fit both to the far infrared spectrum and the rotational constants. This changes the barrier to ring inversion from 1.00 kJ mol−1 to 1.12 kJ mol−1. The vibrational dependence of the centrifugal distortion constants is accounted for satisfactorily by the theory developed by Creswell and Mills. An attempt to reproduce the vibrational dependence of the rotational and centrifugal distortion constants using the ring puckering potential function and a simple model for this vibration has very limited success.  相似文献   
29.
PHOTOINDUCTION OF PROTOPERITHECIA IN NEUROSPORA CRASSA BY BLUE LIGHT   总被引:7,自引:0,他引:7  
Blue light induces the formation of Neurospora crassa protoperithecia.This photoinduction is completed in less than 24 h. Its threshold is about 4.2 J/m2. Red light is ineffective. The Bunsen-Roscoe law is obeyed at the fluence of 12.6 J/m2 for fluence rates from 5.25 × 10 2 to 1.05 W/m2.  相似文献   
30.
We have synthesized nine 2,9-aryl-substituted 1,10-phenanthrolines (1-9) with the aim of rationalizing their electronic absorption and luminescence properties in both the basic and acid form. The latter are generated upon addition of trifluoroacetic acid to CH2Cl2 solutions of 1-9 and their formation is unambiguously evidenced by UV-vis absorption and 1H NMR spectroscopy. 1-9 can be subdivided into three groups, depending on their chemical structure and luminescence behavior. 1-3 are symmetrically substituted p-dianisylphenanthrolines which exhibit relatively intense violet fluorescence in CH2Cl2 (lambda(max) ca. 400 nm, Phi(fl) = 0.12-0.33) and are strongly quenched and substantially red-shifted upon protonation (lambda(max) ca. 550 nm, Phi(fl) = 0.010-0.045). 4-5 are 2,6-dimethoxyphenylphenanthrolines with faint luminescence in both the basic and acid form. 6-9 are various unsymmetric aryl-substituted-phenanthrolines and their relatively strong fluorescence (lambda(max) ca. 400 nm, Phi(fl) = 0.08-0.24) is red-shifted and substantially enhanced following protonation (lambda(max) ca. 475 nm, Phi(fl) = 0.16-0.50). The markedly different trends in the electronic absorption and fluorescence spectra are rationalized by means of both time-dependent Hartree-Fock and density functional theory by using hybrid functionals to assign the excited states. Interestingly, protonation of 1-9 also occurs in spin-coated films simply exposed to vapors of acid, and the reaction can be signaled by the color tuning of the emission signal (vapoluminescence). This observation makes substituted phenanthrolines potential candidates as proton sensors also in the solid phase.  相似文献   
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