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61.
The potential energy function of nitrogen dioxide with the C2v symmetry in the ground state is represented using the simplified Sorbie-Murrell many-body expansion function in terms of the symmetry of NO2. Using the potential energy function, some potential energy surfaces of NO2(C2v, X^-^2A1), such as the bond stretching contour plot for a fixed equilibrium geometry angle θ and contour for O moving around N-O (R1), in which R1 is fixed at the equilibrium bond length, are depicted. The potential energy surfaces are analysed. Moreover, the equilibrium parameters for NO2 with the C2v, Cs and Dsn symmetries, such as equilibrium geometry structures and energies, are calculated by the ab initio (CBS-Q) method. 相似文献
62.
V. Crozatier 《Journal of luminescence》2007,127(1):104-109
We report on the demonstration of the chirp transform algorithm for the instantaneous optical frequency analysis of wide band radiofrequency signals. The process exploits photon echoes in an Er3+:YSO crystal at 1536 nm. The analysis covers a 1.6 GHz instantaneous bandwidth together with more than 24,000 independent channels. These performances require a frequency agile laser source that is phase-locked in order to take advantage of the tens of μs of coherence time offered by the crystal optical transition. 相似文献
63.
We present a new approach to laser interferometric Doppler and ranging (LIDAR) processing using spatial-spectral holography (SSH). In this approach, broadband optical signals from a random noise or frequency-modulated laser are transmitted and reflected off remote targets. The return signals interfere spatially and spectrally with a local copy of the original transmit signal in an SSH medium, resulting in spectral gratings that have a spectral period inversely proportional to the LIDAR target's range and a position proportional to the target's Doppler (or velocity). These gratings are subsequently read out by a slowly chirped source onto a parallel detector array, and the velocity and range of the targets are inferred. We present the theoretical framework that describes the function of the LIDAR processor, as well as proof-of-concept experimental results. 相似文献
64.
R. Arndt W. Briscoe I. Strakovsky R. Workman 《The European Physical Journal A - Hadrons and Nuclei》2008,35(3):311-316
We continue to update our PWA of fundamental reactions as new data become available. Of primary interest to the N* program are πN elastic scattering and the photo- and electroproduction of pions. Other photo-reactions are more model dependent, but may
reveal resonances coupling weakly to πN final states. We also mention recent results from nucleon-nucleon elastic scattering, which have a less well-known connection
to experimental programs proposing to extract N
* properties from complete experiments. 相似文献
65.
T. Ohtsubo T. Azuma M. Takaura T. Higashiguchi S. Kubodera W. Sasaki 《Applied Physics A: Materials Science & Processing》2003,76(2):139-141
We have demonstrated the non-thermal removal of oxygen atoms from an oxidized silicon surface (SiO2) on a silicon wafer by the use of a low-power (0.3 mW cm-2) incoherent vacuum ultraviolet (VUV) light source at 126 nm. X-ray photoelectron spectroscopy (XPS) has shown that a maximum
Si concentration of 80% appears at the surface after a 20-h irradiation with 9.8 eV photons, as a result of oxygen removal
from the SiO2 matrix. The surface morphology, however, indicates no damage or melting on the surface even after the irradiation.
Received: 15 April 2002 / Accepted: 17 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Permanent address: Nano-Tech Photon Inc., Shimotomita 4132-1, Shintomi, Miyazaki, 889-1404, Japan
RID="**"
ID="**"Corresponding author. Fax: +81-985/583-899, E-mail: kubodera@opt.miyazaki-u.jp 相似文献
66.
Parra E. McNaught S.J. Fan J. Milchberg H.M. 《Applied Physics A: Materials Science & Processing》2003,77(2):317-323
The interaction of high intensity 100-ps laser pulses with micron-sized noble gas (argon and krypton) droplets is experimentally
investigated via a series of pump–probe experiments monitoring the delay-dependent X-ray and extreme ultraviolet (EUV) emission,
and by imaging frequency-doubled probe light scattered from the interaction region. An understanding of the time scales for
this interaction is important for optimization of EUV sources for next-generation lithography that utilizes laser-produced
plasmas (LPP). Depending on the spectral region of interest, the type of emission, and the droplet characteristics, the effective
emission lifetime was found to extend from a few hundred picoseconds to as long as several nanoseconds, in agreement with
the expected plasma expansion, EUV excitation, and recombination emission time scales.
Received: 22 August 2002 / Accepted: 8 February 2003 / Published online: 28 May 2003
RID="*"
ID="*"Corresponding author. Fax: +1-301/3149-363, E-mail: riq@wam.umd.edu 相似文献
67.
Jiangli Fan Yunkou Wu Erhu Lu Jun Hou Hongbing Zhang Rong Zhang Xinmei Fu 《Journal of luminescence》2005,114(2):125-130
A new Zn2+ fluorescent sensor NIDPA, with 1,8-naphthalimide as reporting group and di-2-picolylamine (DPA) as recognizing group, has been synthesized via simple steps. Based on photo-induced electron transfer (PET) mechanism, NIDPA has a five-fold fluorescent enhancement and 10 nm absorption blue-shift under simulated physiological conditions corresponding to the binding of Zn2+. Apparent dissociation constant for Zn2+ (Kd) is 0.83 nM, and Ca2+, Mg2+, Fe2+, Ni2+ and Cr3+have little influence on fluorescent enhancement. These results suggest that NIDPA can be used to quantitatively and selectively measure the concentration of Zn2+ around sub-nanomolar range. 相似文献
68.
R.J. Peterson S. de Barros H. Schechter S.G. Mashnik A.G. daSilva J.C. Suita 《The European Physical Journal A - Hadrons and Nuclei》2001,10(1):69-71
Cross-sections for the π+-induced fission of 209Bi and 235U have been measured in small steps across the 3-3 resonance to search for any mechanisms that might signal a change in the
reaction mechanism across a region where strong coupling of available energy into nuclear excitation can be expected. The
bismuth data are found to be in good agreement with a statistical calculation not including new mechanisms.
Received: 15 August 2000 / Accepted: 23 January 2001 相似文献
69.
The individual monitoring service Seibersdorf uses two different passive dosemeter types based on thermo luminescence (TL) detectors for monitoring occupationally exposed persons in Austria. Whole body personal dosemeters for the personal dose equivalent quantities Hp(10) and Hp(0.07) worn on the trunk and dosemeters for the extremities for Hp(0.07) worn on a finger or wrist. Both routine dosemeters were calibrated and tested in terms of the personal dose equivalent Hp(3) assuming that the whole body dosemeter is worn on the chest (without or above a lead apron) and the modified ring/wrist dosemeter using a special strap worn on the forehead near the eyes (head band dosemeter). The test results show that it is possible to measure the dose quantity Hp(3) with these dosemeters that were originally not designed for this dose quantity. Only changes in the dose calculation algorithm and in the choice of the reference radiation quality were necessary to fulfil the requirements given in international standards for passive dosemeters in a wide energy (20 keV–1.3 MeV) and angular range (0°–60°). 相似文献
70.
A. Stampanoni-Panariello D. N. Kozlov P. P. Radi B. Hemmerling 《Applied physics. B, Lasers and optics》2005,81(1):113-129
In this article we review the results achieved in the past ten years at the Paul Scherrer Institute on the topic of diagnostics in the gas phase by laser-induced gratings (LIGs). The technique has been applied for thermometry in air and in flames at different pressures, for flow velocimetry, for concentration measurements, and for imaging purposes. The influence of collisional energy-transfer and relaxation processes in molecules on the temporal evolution of the LIG signals has also been investigated. It has been demonstrated that, for molecules with a low fluorescence quantum yield, excitation of laser-induced thermal gratings can be used as a sensitive spectroscopic tool. For the quantitative interpretation of the experiments shown in this work, the findings presented in the companion paper [1] have been used. 相似文献