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排序方式: 共有336条查询结果,搜索用时 78 毫秒
211.
HO H P 《中国光学与应用光学文摘》2010,(1)
We present an ultra compact and high resolution free space optical spectrometer and demonstrate it by using FDTD simulations. The miniature interferometer-based spectrometer is a series of submicron phase objects on a polymethyl methacrylate(PMMA) film with a CCD as the detector. The spectrum is obtained by solving a system of simultaneous linear equations. The Tikhonov regularization method is used to achieve a resolution at the picometer level. Compared with conventional spectrometers, the proposed device... 相似文献
212.
Daiguji H Hwang J Takahashi A Kataoka S Endo A 《Langmuir : the ACS journal of surfaces and colloids》2012,28(7):3671-3677
Mesoporous silica SBA-16 thin films with highly ordered 3D cubic structures were synthesized on a Si substrate via the dip-coating method. After these films were filled with KCl aqueous solutions, the ionic current passing through the mesopores was measured by applying dc electric fields. At low ion concentrations, the measured I-V curves were nonlinear and the current increased exponentially with respect to voltage. As the ion concentration increased, the I-V curve approached linear behavior. The nonlinear behavior of I-V curves can be reasonably attributed to the electric potential barrier created in nanopores. 相似文献
213.
A laser-plasma source comprising a rotating cryogenic solid-state Xe target has been studied for use in extreme ultraviolet lithography (EUVL) systems equipped with La/B4C mirrors. The laser-to-EUV power conversion efficiency (CE) of the cryogenic Xe target was improved to achieve a maximum CE of 0.15?% at 6.7?nm with 0.6?% bandwidth. We successfully demonstrated the continuous generation of EUV light with an average power of 80?mW at 6.7?nm with 0.6?% bandwidth using a Nd:YAG slab laser at a repetition rate of 320?Hz and an average power of 100?W. Scaling-up of the laser-plasma source for use as a future EUVL source is also discussed. 相似文献
214.
In situ generated lanthanum(iii) nitrate alkoxide is a highly active and nearly neutral transesterification catalyst, which can promote non-epimerized transesterification of α-substituted chiral carboxylic esters under reflux conditions. 相似文献
215.
Sho Takemori 《Journal of Number Theory》2012,132(6):1203-1264
We prove an explicit formula for Fourier coefficients of Siegel–Eisenstein series of degree two with a primitive character of any conductor. Moreover, we prove that there exists the p-adic analytic family which consists of Siegel–Eisenstein series of degree two and a certain p-adic limit of Siegel–Eisenstein series of degree two is actually a Siegel–Eisenstein series of degree two. 相似文献
216.
Using the analytic realization of middle convolution due to Dettweiler and Reiter, we show that any rigid Fuchsian system can be obtained as a subsystem of some generating system which has an integral representation of solutions of Selberg type. Twisted homology groups and twisted cohomology groups associated with such integrals are studied. In particular, contiguity relations and twisted cycles which realize local exponents are obtained. 相似文献
217.
Sho Matsumoto 《Journal of Theoretical Probability》2012,25(3):798-822
We study a random positive definite symmetric matrix distributed according to a real Wishart distribution. We compute general moments of the random matrix and of its inverse explicitly. To do so, we employ the orthogonal Weingarten function, which was recently introduced in the study of Haar-distributed orthogonal matrices. As applications, we give formulas for moments of traces of a Wishart matrix and its inverse. 相似文献
218.
超精密抛光是一种新兴的用于制造高精度、高品质的自由曲面光学加工技术.该技术可突破其他自由曲面加工技术的限制.如飞刀铣削和快刀伺服加工的低效、非铁材料的局限等.然而,对超精密抛光中表面生成机理的理解,目前还不完善.探讨了超精密抛光过程中加工策略对表面生成的影响.进行了一系列抛光实验.研究结果表明:抛光表面的质量很大程度上依赖于加工过程条件及抛光策略的适当选择.抛光加工不仅可用于去除其他加工方式所产生的不利性刀纹,还可以产生功能性应用的结构性表面.该研究结果为深入理解超精密抛光自由曲面光学的表面生成机理,以及优化超精密抛光的表面质量,提供了重要依据和方法. 相似文献
219.
We characterize that the image of the embedding of the Q ‐polynomial association scheme into the first eigenspace by primitive idempotent E 1 is a spherical t‐design in terms of the Krein numbers. Furthermore, we show that the strengths of P‐ and Q‐polynomial schemes as spherical designs are bounded by a constant. Copyright © 2011 John Wiley & Sons, Ltd. 19:167‐177, 2011 相似文献
220.
Atsuhiro Harada Toshiyuki Takagi Sho Kataoka Takuji Yamamoto Akira Endo 《Adsorption》2011,17(1):171-178
Recently, an increase in the use of boron compounds has led to an increase in boron emissions, and concern has grown regarding
its detrimental effects on the human body. An adsorbent that adsorbs boron selectively has been developed as a countermeasure.
Although certain commercially available boron selective adsorbents can be used to remove boron from aqueous solutions by utilizing
the strong affinity between boron and hydroxyl groups, the adsorption capacity appears to be insufficient. So, we adopted
polyvinyl alcohol (PVA), which contains many hydroxyl groups, as a model adsorbent. We investigated the boron adsorption characteristics
of PVA, and then studied the relationship between the number of adsorption sites and actual adsorption amounts. We assessed
the adsorption result by using adsorption site availability (ASA) as an indicator of the ratio of effectively functioning
hydroxyl groups from the many hydroxyl groups in PVA. ASA was expressed as a percentage of the experimental equilibrium adsorbed
amount in relation to the theoretical equilibrium adsorbed amount. We also compared the adsorption isotherms and ASA obtained
with PVA, commercially available N-methylglucamine-type resin (CRB03 and CRB05) and the adsorbent we synthesized from polyallylamine (PAA) and glucose (PAA-Glu).
Although PVA has many hydroxyl groups in a molecule, ASA analysis revealed that only 6% of the hydroxyl groups in PVA was
used for boron adsorption. On the other hand, CRBs and PAA-Glu exhibited higher ASA values (about 15% and 35% respectively)
and adsorption amounts, suggesting that the sterically congested adsorbent structure had a great influence on boron adsorption
and ASA. 相似文献