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91.
Hydrogen peroxide (H2O2) in exhaled breath condensate (EBC) has been proposed as a marker for oxidative stress in the airways. The aim of the present study was to evaluate the measurement of H2O2 in EBC with or without use of a nose clip, and the influence of mouth rinsing, sampling time and storage.An elevated H2O2 level was seen during nasal breathing compared to mouth breathing with nose clip (3.4 pmol/s vs. 2.1 pmol/s, p = 0.02). Breathing through the mouth, using a nose clip, was therefore practiced in all experiments. The H2O2 levels were increased when mouth rinsing was performed using an acid buffer (1.4 pmol/s vs. 1.9 pmol/s, p = 0.03). 15 min sampling time decreased the H2O2 output by almost 50% compared with 2 min sampling time (1.2 vs. 0.6 pmol/s, p = 0.03). When samples were left unattended for 15 min no change in H2O2 concentration in the EBC was seen.We found no significant differences in H2O2 levels between samples stored for 4 weeks at − 80 °C and samples analysed directly; however, a significant decrease in the levels was seen for samples stored for 4 weeks at − 20 °C.In conclusion, the method of EBC collection and storage plays an important role in reducing variability within and between individuals. 相似文献
92.
Three types of two bright bound solitons with increasing coherence are investigated in the Bose-Einstein condensates (BECs) with the exponentially time-dependent interparticle interaction in an expulsive parabolic potential. Two methods are provided with symbolic computation to improve the number of matter density peaks within the given temporal range before the collapse of the solitons under the one-dimensional approximation: (i) enhancing the axial harmonic oscillator frequency; (ii) increasing the initial coherence of the bound solitons. Compression of the three- and four-bright-bound-soliton trains is presented. Estimation of the net binding forces among the bound solitons gives an explanation for the interaction patterns if the coherence of the bound state is limited. Our investigation theoretically reveals the existence of the bright bound solitons in the BECs and analyzes their complex interactions. 相似文献
93.
94.
V. P. Maslov 《Mathematical Notes》2006,80(5-6):806-813
We introduce the notion of weight for the asymptotic topological dimension. Planck’s formula for black-body radiation is refined. We introduce the notion of negative asymptotic topological dimension (of hole dimension). The condensate in the hole dimension is applied to the quantized Zipf law for frequency dictionaries (obtained earlier by the author). 相似文献
95.
缩酮胺合锌催化二氧化碳和氧化环己烯共聚 总被引:11,自引:5,他引:6
二氧化碳作为单体与环氧化物的共聚反应近年来越来越受到重视 .该反应不经过高耗能的还原过程 ,二氧化碳利用率高 ,所得到的产物聚碳酸酯在塑料、弹性体、涂料、胶粘剂、食品包装材料和生物降解材料等方面有广泛的应用 .二氧化碳与氧化环己烯的交替共聚物聚碳酸亚环己酯玻璃化转变温度较高 (Tg 为 1 2 0℃ ) ,热分解温度达 2 1 0℃以上[1] ,是一种性能优良的高分子材料 .Cheng等于 1 998年首次报道了一种缩酮胺合锌催化剂[2 ] .它是由 β 二酮 (乙酰丙酮 )与 2 ,6 二异丙基苯胺为原料合成的 ,具有西佛碱结构 ,用于二氧化碳与氧化环己… 相似文献
96.
In this letter,the superfluid-Mott-insulator phase transition of two-species cold bosonic atoms in an optical lattices is studied.The Hamiltonian of this model is diagonalized by means of Bogliubov transformations and by the inversion symmetry of the optical lattice,the energy spectrum of this system is obtained.From the energy gap of the excitation spectrum,the quantum phase transition condition is obtained and it is determined by the competition between the interatomic repulsions and the tunnel coupling.It is found that there exists an ordinary fluid phase when taking the zero wave-vector limit. 相似文献
97.
We propose a new measurement scheme for the atom-molecule dark state by using electromagnetically induced transparency (EIT) technique. Based on a density-matrix formalism, we calculate the absorption coefficient numerically. The appearance of the EIT dip in the spectra profile gives clear evidence for the creation of the dark state in the atom-molecule Bose-Einstein condensate. 相似文献
98.
WANG Tian-Yuan 《理论物理通讯》2009,51(2):255-258
We consider the one-dimensional nonlinear Schrǒdinger equations that describe the dynamics of a Bose-Einstein Condensates with time-dependent scattering length in a complex potential. Our results show that as long as the integrable relation is satisfied, exact solutions of the one-dimensional nonlinear Schrǒdinger equation can be found in a general closed form, and interactions between two solitons are modulated in a complex potential We find that the changes of the scattering length and trapping potential can be effectively used to control the interaction between two bright soliton. 相似文献
99.
In this letter, we have studied the tunneling effects and fluctuations of spinor Bose-Einstein condensates in optical lattice. It is found that there exist tunneling effects and fluctuations between lattices l and l 1, l and l - 1,respectively. In particular, when the optical lattice is infinitely long and the spin excitations are in the long-wavelength limit, tunneling effects disappear between lattices l and l 1, and l and l - 1. In this case the fluctuations are a constant,and the magnetic soliton appears. 相似文献
100.
The physics of the initial conditions of heavy ion collisions is dominated by the nonlinear gluonic interactions of QCD. These lead to the concepts of parton saturation and the Color Glass Condensate (CGC). We discuss recent progress in calculating multigluon correlations in this framework, prompted by the observation that these correlations are in fact easier to compute in a dense system (nucleus–nucleus) than a dilute one (proton–proton). 相似文献