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A. B. Lobo Ribeiro J. L. Santos J. M. Baptista L. A. Ferreira F. M. Araú jo A. P. Leite 《Fiber and Integrated Optics》2005,24(3):171-199
A general overview of the R&D activity in fiber optic sensing developed over the last fifteen years in Portugal is given. Different topics are addressed, including interferometric, intensity and Bragg grating based fiber optic sensors, signal processing and multiplexing techniques, optical current sensors, together with some references to field trials and applications. Possible guidelines for present and future national R&D activity on this subject are outlined. 相似文献
254.
A rapid and selective method has been developed for radiochemical separation, and determination of Cs in complex matrices by thermal neutron activation analysis. Batch adsorption of 134Cs was carried out on zirconium phosphate ion exchanger. A large number of samples of the ore have been analysed for their Cs content and the results are discussed. 相似文献
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Gomes MJ Sharma L Prabhakar S Lobo AM Glória PM 《Chemical communications (Cambridge, England)》2002,(7):746-747
On thermolysis appropriately substituted N-silyloxy-N-allyl enamines undergo smooth 3,3-sigmatropic rearrangments to the corresponding N-silyloxy imino ethers. 相似文献
257.
Santander-Syro AF Lobo RP Bontemps N Konstantinovic Z Li Z Raffy H 《Physical review letters》2002,88(9):097005
The ab-plane reflectance of Bi(2)Sr(2)CaCu(2)O(8+delta) (Bi-2212) thin films was measured in the 30-25 000 cm(-1) range for one underdoped ( T(c) = 70 K), and one overdoped sample ( T(c) = 63 K) down to 10 K. We find similar behaviors in the temperature dependence of the normal-state infrared response of both samples. Above T(c), the effective spectral weight, obtained from the integrated conductivity, does not decrease when T decreases, so that no opening of an optical pseudogap is seen. We suggest that these are consequences of the pseudogap opening in the k = (0,pi) direction and of the in-plane infrared conductivity being mostly sensitive to the k = (pi,pi) direction. 相似文献
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Farías D Kamiński W Lobo J Ortega J Hulpke E Pérez R Flores F Michel EG 《Physical review letters》2003,91(1):016103
The phonon dynamics of the Sn/Ge(111) interface is studied using high-resolution helium atom scattering and first-principles calculations. At room temperature we observe a phonon softening at the Kmacr; point in the (sqrt[3]xsqrt[3])R30 degrees phase, associated with the stabilization of a (3x3) phase at low temperature. That phonon band is split into three branches in the (3x3) phase. We analyze the character of these phonons and find out that the low- and room-temperature modes are connected via a chaotic motion of the Sn atoms. The system is shown to present an order-disorder transition. 相似文献
260.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献