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211.
D.C. Kulkarni 《Microelectronics Journal》2008,39(2):248-252
The thick film NixZn(1−x)Fe2O4 on alumina substrate was prepared by screen printing of the ferrite powder synthesized by chemical co-precipitation method using nitrate precursors. These NixZn(1−x)Fe2O4 thick films of varying x were characterized by X-ray diffraction, FTIR spectroscopy and SEM (scanning electron microscopy). The permittivity and permeability were measured by overlay technique. Voltage standing wave ratio method was also used to measure the dielectric constant. The permittivity was found to increase with Ni content varying between 13 and 18. The permeability was ∼3.01. The overlay technique provides an easy method for measurement of permittivity and permeability of ferrite thick film. 相似文献
212.
N. Jacquinet-Husson N.A. Scott L. Crépeau V. Capelle A. Coustenis N. Poulet-Crovisier M. Birk C. Camy-Peyret K. Chance C. Clerbaux P.F. Coheur L. Daumont G. Di Lonardo A. Goldman M. Hess D. Jacquemart P. Köpke S. Massie V. Nemtchinov D. Newnham V.I. Perevalov L. Régalia-Jarlot A. Rublev L. Schult S.A. Tashkun R.A. Toth J. Vander Auwera G. Wagner 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(6):1043-1059
The development of Gestion et Etude des Informations Spectroscopiques Atmosphériques (GEISA: Management and Study of Spectroscopic Information) was started over three decades at Laboratoire de Météorologie Dynamique (LMD) in France. GEISA is a computer accessible spectroscopic database, designed to facilitate accurate forward radiative transfer calculations using a line-by-line and layer-by-layer approach. More than 350 users have been registered for on-line use of the GEISA facilities. The current 2003 edition of GEISA (GEISA-03) is a system comprising three independent sub-databases devoted respectively to: line transition parameters, infrared and ultraviolet/visible absorption cross-sections, microphysical and optical properties of atmospheric aerosols.Currently, GEISA is involved in activities related to the assessment of the capabilities of IASI (Infrared Atmospheric Sounding Interferometer on board of the METOP European satellite) through the GEISA/IASI database derived from GEISA.The GEISA-03 content is presented, placing emphasis on molecular species of interest for Earth and planetary atmosphere studies, with details on the updated 2008 archive underway. A critical assessment on the needs, in terms of molecular parameters archive, related with recent satellite astrophysical missions is made. Detailed information on free on-line GEISA and GEISA/IASI access is given at http://ara.lmd.polytechnique.fr and http://ether.ipsl.jussieu.fr. 相似文献
213.
214.
N. Ibrahim J. Orphal 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(15):2523-2536
The absorption spectrum of H2O has been extensively studied over the past decades in the near-infrared and visible regions, but there remain significant discrepancies in the 10,000-12,500 cm−1 range even for the most intense lines. We have studied 24 lines of H2O using an external-cavity diode laser emitting in the 810-830 nm range, in order to measure absolute line intensities as well as air- and self-broadening coefficients. Comparisons were made with values obtained from the HITRAN database and also with other parameters from recent experiments or predicted calculations. It is suggested that neglecting the effects of H2O collisional narrowing in radiative transfer calculations of the Earth's atmosphere may have a small but significant impact on the radiative budget of the Earth. 相似文献
215.
We measured room-temperature H2O spectra of the 3ν polyad within the wave number range 10 603 cm−1 to 10 852 cm−1 using frequency-stabilized cavity ring-down spectroscopy. More than 70 transitions, divisible into two groups based on their relative intensities (strong and weak) were investigated. For the 23 lines comprising the set of strong transitions, the water vapor sample was prepared as a dilute mixture in a steady flow of N2 carrier gas, and the measurement of the water vapor sample number density was linked to primary methods of humidity generation. For these strong transitions, the measured line intensities were within 1% of previous measurements. The line intensity measurements of the weaker H2O transitions, were made on samples of static pure water vapor, and these results were systematically greater than previous measurements by approximately 20%. 相似文献
216.
The absorption spectrum of 14N15N16O-enriched sample of nitrous oxide has been recorded at Doppler limited resolution with a Fourier-transform spectrometer in the spectral range 3500-9000 cm−1. More than 12 000 transitions of 14N15N16O were observed and ro-vibrationally assigned on the basis of the global effective Hamiltonian model. The band-by-band analysis led to the determination of the ro-vibrational parameters of a total of 107 bands. Among the 107 bands, 80 are newly observed, for 27 others the rotational analysis is significantly extended and improved. The effective Hamiltonian parameters are determined from global fitting to the observed line positions presented in this paper and collected from the literature. As a result, a set of 117 obtained effective Hamiltonian parameters reproduces 16 134 observed line positions of 148 bands with RMS of 0.0014 cm−1. 相似文献
217.
Sergei V. Shirin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(4):549-558
A line list for D2 16O isotopologue of water molecule was calculated in the region 0-16,000 cm−1 with energy levels up to J=30. Variational calculations are based on the semi-theoretical potential energy surface obtained by morphing ab initio potential using the experimental energy levels of D2 16O. For energy levels with J=0, 2, 5 and 10, the standard deviation of the fit is 0.023 cm−1. This line list should make an excellent starting point for spectroscopic modeling and analysis of D2O rovibrational spectra. 相似文献
218.
Serhan Yamacli Caner Ozdemir Ali Akdagli 《International Journal of Infrared and Millimeter Waves》2008,29(2):207-216
This paper presents a simple method for determining the dielectric constant of microwave PCB substrates. In the presented
method, a bandpass microstrip filter designed on the PCB substrate with a user-predicted dielectric constant value is implemented
for a given center frequency. The simulation results of the designed bandpass filter are obtained by the help of microwave
design software; XFDTD?. Experimental results regarding the filter frequency characteristic are accomplished by means of a
vector network analyzer. The simulation results of the designed filter are modified to overlap with the experimental ones
by varying the dielectric constant value. When the simulation and experimental results are overlapped, the value of dielectric
constant is accurately selected. In order to illustrate the validity of proposed method, the dielectric constant values of
flame resistant-4 (FR4) substrates are acquired at IEEE 802.11b/g and IEEE 802.11a wireless local area network (WLAN) application
frequencies. The results obtained by using the presented method agree with the previous studies in the literature. 相似文献
219.
220.