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51.
R. Lo Franco G. Compagno A. Messina A. Napoli 《The European physical journal. Special topics》2008,160(1):247-257
We show that the N-photon generalized binomial states of electromagnetic field may be put in a bijective mapping with the
coherent atomic states of N two-level atoms. We exploit this correspondence to simply obtain both known and new properties
of the N-photon generalized binomial states. In particular, an over-complete basis of these binomial states and an orthonormal
basis are obtained. Finally, the squeezing properties of generalized binomial state are analyzed. 相似文献
52.
Le Gouët J Morvan L Alouini M Bourderionnet J Dolfi D Huignard JP 《Optics letters》2007,32(9):1090-1092
We demonstrate the generation of optically carried, broadly tunable, millimeter-wave signals with a dual-frequency single-axis Nd:YAG laser. A frequency difference as high as 127 GHz is reached thanks to an intracavity electro-optically tunable etalon made of lead zirconate tantalate (PLZT) ceramic. We show that the available frequency range is actually limited by the bandwidth of the amplification medium, namely, far beyond the usually accepted free spectral range value in the case of a single-axis laser. Both coarse discrete and fine continuous tunabilities are obtained with the same voltage-controlled device, opening the way to widely tunable low-phase-noise optically carried submillimeter or even terahertz sources. 相似文献
53.
54.
Fu-Ming Wang Chien-Chieh Hu Shen-Chuan Lo Yung-Yun Wang Chi-Chao Wan 《Solid State Ionics》2009,180(4-5):405-411
The effect of EO side chain functionalization on the transport and electrochemical properties of polysiloxane electrolytes has been examined in this report. First, a study of the electrochemical stability of the electrolytes by linear sweep voltammetry shows that the polymer electrolytes have a negligible effect on the electrolyte stability windows. In addition, the parameters of cation mobility in polysiloxane electrolytes, such as ionic transference numbers and diffusion coefficients, were increased by increasing the lengths of the EO side chain. However, cation mobility in polymer structures is quite different compared to liquid-based systems and is probably suppressed, resulting in their polymer structure. Therefore, Positron Annihilation Lifetime Spectroscopy (PALS) was used to study the relationship between orthopositronium (o-Ps) lifetime, free volume radius, free volume of micro voids and EO side chain affection at different temperatures. Finally, a battery application with LiCoO2 and LiFePO4/polymer electrolyte/lithium metal electrode was monitored for its potential use in the future. 相似文献
55.
Kang-Chieh Lo Chiao-Yin Sun Yu-Ju Ding Jen-Ning Tsai Kai-Ping Chang Yi-En Wen Wan-Ling Chang Shin C. Chang Ming-Fu Chang Yun-Hsin Wang Yau-Hung Chen 《Research on Chemical Intermediates》2014,40(6):2177-2185
Benzo(a)pyrene is a chemical produced during the process of making fried, roasted, and smoked foods. It remains unclear whether benzo(a)pyrene affects the early development of human organs. In this study, we used the transgenic zebrafish line Tg(wt1b:GFP) as a model to assess benzo(a)pyrene-induced kidney malformation. By soaking zebrafish embryos in benzo(a)pyrene at various doses (2, 20, and 200 ppb), only a minor effect on the survival rate was detected (0 ppb: 97.8 ± 1.9 %; 2–200 ppb: 89.1 ± 5.8–91.5 ± 8.3 %). However, benzo(a)pyrene significantly affected the development of the kidney (malformation rates ranges from 50.0 ± 3.5 to 77.4 ± 5.3 %). Various abnormalities, such as unusual curving of pronephric tubes, swollen glomerulus, and incomplete development of pronephric ducts, were observed. This study provides a rapid and effective protocol for the evaluation of the notable effects of benzo(a)pyrene on embryonic kidney development. 相似文献
56.
Cellulase could not be selectively collected from fermentation broth by simple foam fractionation, because of the presence
of other more surface-active compounds. A new approach of affinity foam fractionation was investigated for improvement. A
hardwood hydrolysate (containing cellulose oligomers, substrates to cellulase) and two substrate analogs, i.e., carboxymethyl
cellulose (CMC) and xylan hydrolysate, were added before the foaming process. The substrates and substrate analogs were indeed
found to bind the cellulase selectively and form more hydrophobic complexes that partition more readily onto bubble surfaces.
In this study, the effects of the type and concentration of substrate/analog as well as the presence of cells at different
growth stages were examined. The foam fractionation properties evaluated included foaming speed, foam stability, foamate volume,
and enrichment of filter paper unit (FPU) and individual cellulase components (i.e., endoglucanases, exoglucanases, and β-glucosidases).
Depending on the broth and substrate/analog employed, the foamate FPU could be more than fourfold higher than the starting
broth FPU. Addition of substrate/analog also deterred the enrichment of other extracellular proteins, resulting in the desired
cellulase purification in the foamate. The value of E/P (enzyme activity-FPU/g/L of proteins) in the foamate reached as high
as 18, from a lactose-based fermentation broth with original E/P of 5.6. Among cellulase components, exoglucanases were enriched
the most and β-glucosidases the least. The study with CMC of different molecular weights (MW) and degrees of substitution
(DS) indicated that the CMC with low DS and high MW performed better in cellulase foam fractionation. 相似文献
57.
Kobra Mahdavipour Mahshid Khazaei Shadfar Hossein Rangani Jahromi Roberto Morandotti Rosario Lo Franco 《Entropy (Basel, Switzerland)》2022,24(3)
A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a non-Markovianity witness is particularly useful, being easily computable since no diagonalization of the system density matrix is required. We investigate the sensitivity of this HSS-based witness to detect non-Markovianity in various high-dimensional and multipartite open quantum systems with finite Hilbert spaces. We find that the time behaviors of the HSS-based witness are always in agreement with those of quantum negativity or quantum correlation measure. These results show that the HSS-based witness is a faithful identifier of the memory effects appearing in the quantum evolution of a high-dimensional system with a finite Hilbert space. 相似文献
58.
We describe a protocol for distilling maximally entangled bipartite states between random pairs of parties from those sharing a tripartite W state |W=(1/sqrt[3])(|100+|010+|001)(ABC), and show that the total distillation rate E(t)(infinity) [the total number of Einstein-Podolsky-Rosen (EPR) pairs distilled per W, irrespective of who shares them] may be done at a higher rate than EPR distillation between specified pairs of parties. Specifically, the optimal rate for distillation to specified parties has been previously shown to be 0.92 EPR pairs per W, while our protocol can asymptotically distill 1 EPR pair per W between random pairs of parties, which we conjecture to be optimal. We thus demonstrate a tradeoff between overall distillation rate and final distribution of EPR pairs. We further show that there exist states with fixed lower-bounded E(t)(infinity), but arbitrarily small distillable entanglement for specified parties. 相似文献
59.
Temperature dependent behavior of the responsivity of InAs/GaAs quantum dot infrared photodetectors was investigated with detailed measurement of the current gain. The current gain varied about two orders of magnitude with 100 K temperature change. Meanwhile, the change in quantum efficiency is within a factor of 10. The dramatic change of the current gain is explained by the repulsive coulomb potential of the extra carriers in the QDs. With the measured current gain, the extra carrier number in QDs was calculated. More than one electron per QD could be captured as the dark current increases at 150 K. The extra electrons in the QDs elevated the Fermi level and changed the quantum efficiency of the QDIPs. The temperature dependence of the responsivity was qualitatively explained with the extra electrons. 相似文献
60.
Libration point trajectory design 总被引:1,自引:0,他引:1
Orbits about the Sun–Earth L
1 and L
2 libration points have become very popular for space physics and astrophysics missions. Due to the hyperbolicity of the region
of phase space where these orbits are found, they are difficult to compute and analyze. The invariant manifold structure provided
by dynamical systems theory has been useful to compute transfer trajectories between orbits. These methods are very promising
and require further development. This systematic approach is a great improvement from the difficult and labor-intensive numerical
search methods currently popular in the astrodynamics community for studying these orbits. The geometric constraints and mission
critical issues are discussed to give the numerical dynamical systems community some insight into the practical considerations
and important problems of interest to the space mission designers. It is hoped that this communication will lead to more fruitful
exchanges between the two communities.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献