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991.
992.
993.
This paper provides a noval solution to optimize the characteristics of a miniature coarse wavelength division multiplexing (mini-CWDM) module by employing collimators with plano-convex rod lenses of different radii. The 8-channel modules before optimization show maximum loss of 0.77 dB and nonuniformity of 0.34 dB. After optimization, the maximum loss and nonuniformity are reduced to 0.50 dB and 0.11 dB, respectively. 相似文献
994.
Xuan Feng Feng-Sheng Zhao 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(4-5):247-255
In order to retrieve from high spectral resolution measurements with high accuracy, it is necessary to be able to evaluate the transmittance precisely. However, the uncertainty of the spectroscopic parameters is one of the most important contributions that affect the accuracy of transmittance. HITRAN is a compilation of spectroscopic parameters which has been updated several times. The transmittance calculations using the line parameters from the HITRAN’2000 database and the HITRAN’2004 database have been compared over the near infrared range from 4200 to 10,000 cm?1. The differences between calculated transmittances over this spectral range are mainly caused by changes of the line parameters for H2O, CO2 and CH4. For the tropical atmosphere, the differences are very prominent. Transmittance calculations for the sub-arctic winter atmosphere are less sensitive to the changes in the HITRAN database than those for the tropical atmosphere; but, the changes of line parameters still can not be ignored when considering the relative differences. For example, the relative difference is ~35% at 5073.3 cm?1 with 0.2 cm?1 spectral resolution. The comparisons have shown that it is important to pay attention to the changes of line parameters of the HITRAN database or to use the latest edition so as to improve the accuracy of atmospheric sounding with high spectral resolution. 相似文献
995.
Huabin Ge Mingxing Luo Qiping Su Ding Wang Xiao Zhang 《General Relativity and Gravitation》2011,43(10):2729-2742
We study the Bondi-Sachs rockets with nonzero cosmological constant. We observe that the acceleration of the systems arises
naturally in the asymptotic symmetries of (anti-) de Sitter spacetimes. Assuming the validity of the concepts of energy and
mass previously introduced in asymptotically flat spacetimes, we find that the emission of pure radiation energy balances
the loss of the Bondi mass in certain special families of the Bondi-Sachs rockets, so in these there is no gravitational radiation. 相似文献
996.
997.
A novel fluorine-contained random copolymer (2,3,4,5,6-pentafluorostyrene)-r-poly(4-vinyl benzocyclobutene) (P(PFSt-r-4-VBCB)) was synthesized, and then spin-coated onto Si substrates followed by thermal cross-linking to produce the copolymer ultra-thin films. Although the surface modification with the P(PFSt-r-4-VBCB) film was simple and did not rely on special surface chemical reactions, the film could decrease the surface energy significantly, more importantly; the film demonstrated excellent stability and corrosion resistance. This random copolymer film could find broad applications in modifying various solid surfaces to enhance the properties such as corrosion resistance and solvent resistance. 相似文献
998.
999.
D.H. Shen A. Berlinger E. Nold W. Lai G.M. Luo 《Applied Physics A: Materials Science & Processing》1999,68(4):425-428
Received: 13 August 1998 / Published online: 10 February 1999 相似文献
1000.
Dong Xi XiaoPing Luo QiangHua Lu KaiLun Yao ZuLi Liu Qin Ning 《Journal of nanoparticle research》2008,10(3):393-400
Gold-coated iron oxide nanoparticle Hepatitis B virus (HBV) DNA probes were prepared, and their application for HBV DNA measurement
was studied. Gold-coated iron oxide nanoparticles were prepared by the citrate reduction of tetra-chloroauric acid in the
presence of iron oxide nanoparticles which were added as seeds. With a fluorescence-based method, the maximal surface coverage
of hexaethiol 30-mer oligonucleotides and the maximal percentage of hybridization strands on gold-coated iron oxide nanoparticles
were (120 ± 8) oligonucleotides per nanoparticle, and (14 ± 2%), respectively, which were comparable with those of (132 ± 10)
and (22 ± 3%) in Au nanoparticle groups. Large network aggregates were formed when gold-coated iron oxide nanoparticle HBV
DNA gene probe was applied to detect HBV DNA molecules as evidenced by transmission electron microscopy and the high specificity
was verified by blot hybridization. Our results further suggested that detecting DNA with iron oxide nanoparticles and magnetic
separator was feasible and might be an alternative effective method. 相似文献