149 resultados para 6 1 Writing Traits
Resumo:
<p><img src="http://img35.ddimg.cn/4/29/20527555-1_l.jpg" border="0" alt="" hspace="8" width="105" height="150" align="left" />14125689101114.</p><div class="mt"><h2> </h2></div><div class="mc"><div class="con" style="height: auto; overflow: hidden"><br /><br />1 <br />1.1 <br />1.2 <br />1.3 <br />1.4 <br /><br /><br />2 <br />2.1 <br />2.2 <br />2.3 <br />2.4 <br />2.5 KC<br />2.6 <br /><br /><br />3 <br />3.1 Williams<br />3.2 <br />3.3 <br />3.4 <br />3.5 <br />3.6 <br /><br /><br />4 <br />4.1 <br />4.2 <br />4.3 <br />4.4 KR<br /><br /><br />5 <br />5.1 <br />5.2 <br />5.3 <br />5.4 <br />5.5 <br />5.6 <br />5.7 <br /><br /><br />6 <br />6.1 J<br />6.2 HRR<br />6.3 J<br />6.4 J<br />6.5 JIC<br />6.6 Dugdale<br />6.7 <br />6.8 <br /><br /><br />7 <br />7.1 <br />7.2 <br />7.3 5<br />7.4 J-Q<br />7.5 J-k<br />7.6 <br /><br /><br />8 <br />8.1 v=0.5<br />8.2 v<0.5<br />8.3 <br />8.4 J<br /><br /><br />9 <br />9.1 <br />9.2 <br />9.3 <br />94<br />95<br />96<br />97<br /><br /><br />10 <br />101<br />102<br />10.3 <br />10.4 <br /><br /><br />11 <br />11.1 <br />11.2 <br />11.3 <br />11.4 Laplace<br />11.5 Wiener-Hopf<br />11.6 <br /><br /><br />12 <br />121<br />12.2 <br />12.3 <br />124<br />12.5 <br /><br /><br />13 <br />13.1 <br />132<br />133<br />13.4 Broberg<br />13.5 <br />136<br />13.7 <br />13.8 II<br />13.9 III<br /><br /><br />14 <br />14.1 <br />14.2 <br />14.3 <br /><br /></div></div>
Resumo:
YAG(extreme ultraviolet).,.:250mJ,,13.5nm0.27nm1.6%,1.81011W/cm2.
Resumo:
A simple three-axis model has been developed, which has been successfully applied to the analysis of the light transmittance in spatial incident angle and the simulation of modified formula of Malus' law for Glan-Taylor prisms. Our results indicate that the fluctuations on the cosine squared curve are due to specific misalignments between the axis of the optical system, the optical axis of the prism and the mechanical axis (rotation axis) of prism, which results in the fact that different initial relative location of the to-be-measured-prism in the testing system corresponds to different shape of Malus' law curve. Methods to get absolutely smooth curve are proposed. This analysis is available for other kinds of Glan-type prisms. (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
Tris-thenoyltrifluroacetonate of Nd3+ has been prepared and dissolved in DMF solation with very high concentration, and the contained hydrogen has not been substituted by deuterium. The absorption spectrum, emission spectrum, and fluorescence lifetime of the solution were measured. Very obvious characteristic fluorescence peaks were observed at 898 and 1058 nm. Based on Judd-Ofelt theory, three intensity parameters were obtained: Omega(2) = 4.9 x 10(-20) cm(2), Omega(4) = 5.1 x 10(-20) cm(2) and Omega(6) = 2.5 x 10(-20) cm(2). Line strengths S-cal, oscillator strengths f(cal), radiative transition probabilities A(ed), radiative lifetimes tau(r) and branch ratios beta were calculated too. The measured lifetime tau of 1058 nm peak is 460 mu s, and that of 898 nm 505 mu s. Comparison between theoretically computed radiative lifetime tau(r)(682 mu s) and the measured lifetime indicates that the non-radiative transition probability of the solution is very low and the fluorescence quantum efficiency very high. High values of three intensity parameters prove the high asymmetric surroundings of Nd3+, which is important for Nd3+ to absorb the excitation energy. Spectropic quality factor Omega(4)/Omega(6) > 1 makes radiation at 898 nm stronger than at 1058 nm.
Resumo:
,B,B,B
Resumo:
Judd-Oflettt=2462=81510^-20,4=14310^-20,6=12210^-202,6Er-OMcCumber4I13/24I15/2c=O51pm^21060ms66
Resumo:
TeO2-ZnO-PbCl2977nm153m^4I13.2^4I15/2(69nm)^2H11/2^4I15/2(527nm)^4S3/2^4I15/2(549nm)^4R9/2^4I15/2(666nm)Judd-Ofelt1(t=246)2=58710^20cm^2,4=20810^2-cm^2
Resumo:
Dy3+ doped oxyfluoride silicate glass was prepared and its optical absorption, 1.3 mu m emission, and upconversion luminescence properties were studied. Furthermore, the Judd-Ofelt [Phys. Rev. 127, 750 (1962); J. Chem. Phys. 37, 511 (1962)] intensity parameters, oscillator strengths, spontaneous transition probability, fluorescence branching ratio and radiative lifetime were calculated by Judd-Ofelt theory, while stimulated emission cross section of H-6(9/2)+F-6(11/2)-> H-6(15/2) transition was calculated by McCumber theory [Phys. Rev. A. 134, 299 (1964)]. According to the obtained Judd-Ofelt intensity parameters Omega(2)=2.69x10(-20) cm(2), Omega(4)=1.64x10(-20) cm(2), and Omega(6)=1.64x10(-20) cm(2), the radiative lifetime was calculated to be 810 mu s for 1.3 mu m emission, whose full width at half maximum and sigma(e) were 115 nm and 2.21x10(-20)cm(2), respectively. In addition, near infrared to visible upconversion luminescence was observed and evaluated. The results suggest that Dy3+ doped oxyfluoride silicate glass can be used as potential host material for developing broadband optical amplifiers and laser applications.
Resumo:
Intense Tm3+ blue upconversion emission has been observed in Tm3+-Yb3+ codoped oxyfluoride tellurite glass under excitation with a diode laser at 976 nm. Three emission bands centered at 475, 650 and 796 nm corresponding to the transitions (1)G(4) -> H-3(6), (1)G(4) -> H-3(4) and F-3(4) -> H-3(6), respectively, simultaneously occur. The dependence of upconversion intensities on Tm3+ ions concentration and excitation power are investigated. For fixed Yb2O3 concentrations of 5.0 mol%, the maximum upconversion intensity was obtained with Tm2O3 concentration of about 0.1 mol%. The blue upconversion luminescence lifetimes of the Tm3+ transitions (1)G(4) -> H-3(6) are measured. The results are evaluated by the possible upconversion mechanisms.
Resumo:
Novel oxyfluoride glasses are developed with the composition of 30SiO(2)-15Al(2)O(3)-28PbF(2)-22CdF(2)-0.1TmF(3)-xYbF(3) -(4.9-x) AlF3(x = 0, 0.5, 1.0, 1.5, 2.0) in mol fraction. Furthermore, the upconversion luminescence characteristics under a 970nm excitation are investigated. Intense blue, red and bear infrared luminescences peaked at 453nm, 476nm, 647nm and 789nm, which correspond to the transitions of Tm3+: D-1(2) -> F-3(4), (1)G(4) -> H-3(6), (1)G(4) -> F-3(4), and H-3(4) -> H-3(6), respectively, are observed. Due to the sensitization of Yb3+ ions, all the upconversion luminescence intensities are enhanced considerably with Yb3+ concentration increasing. The upconversion mechanisms are discussed based on the energy matching rule and quadratic dependence on excitation power. The results indicate that the dominant mechanism is the excited state absorption for those upconversion emissions.
Resumo:
A series of tellurite glasses of composition, 75TeO(2)-20ZnO-(5 - x)La2O3-xEr(2)O(3) (x = 0.05, 0.1, 0.3, 0.6, 1.0, 2.0, and 3.0 mol%) with different hydroxl content were prepared. The effect of Er3+ and OH- groups concentration on the emission properties of Er3+: I-4(13/2) -> I-4(15/2) transition in tellurite glasses was investigated. The constant KOH-Er for Er3+ in tellurite glasses, which represents the strength of interaction between Er3+ and OH- groups in the case of energy migration, was about 14 x 10(-19) cm(4) s(-1). The interaction parameter C-Er,C-Er for the migration rate of Er3+ : 4I(13/2) -> I-4(13/2) transition in tellurite glass was 46 x 10(-40) cm(2), which indicates that concentration quenching in Er3+-doped modified tellurite glass for a given Er3+ concentration is much stronger than in silicate and phosphate glasses. (c) 2007 Elsevier B.V. All rights reserved.
