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191.
Alfonso Carriazo Luis M. Fernández María Belén Hans-Uber 《Acta Mathematica Hungarica》2005,107(4):267-285
Summary We study some special types of slant submanifolds of S-manifolds related to the second fundamental form of the immersion: totally f-geodesic and f-umbilical, pseudo-umbilical and austere submanifolds. We also give several examples of such submanifolds. 相似文献
192.
AISI304钢表面低电压等离子体基离子注入层摩擦磨损性能研究 总被引:6,自引:0,他引:6
采用高频低电压等离子体浸没离子注入(HLPIII)技术对AISI304不锈钢表面进行了氮离子注入处理;用球-盘摩擦磨损试验机考察了注入处理后钢表面改性层的摩擦磨损性能;用扫描电子显微镜(SEM)、俄歇电子能谱仪(AES)和X射线衍射(XRD)考察了改性层的相组成、N元素的深度分布及磨损机理。研究结果表明:HLPIII处理能够显著提高样品的摩擦学性能,且其摩擦学性能对温度有较大的依赖性,400℃下处 相似文献
193.
Facile fabrication of porous NiO films for lithium-ion batteries with high reversibility and rate capability 总被引:1,自引:0,他引:1
We report the high-rate capability and good cyclability of three-dimension nanoporous NiO films as the anodes of lithium-ion
batteries. The NiO films are fabricated by immersing foam nickel substrates in an 80 °C aqueous solution containing ammonia
and potassium peroxydisulfate, and subsequent heat treatment at 500 °C. At a rate of 1.0 C, the film electrodes maintain a
capacity of 560 mAh g−1 as well as capacity retention of 97% after 100 discharge/charge cycles. When the current density is increased to 14C, 42%
of the capacity can be retained. Owing to the ease of large-scale fabrication and superior electrochemical performance, these
NiO films will be promising anodes for high-energy-density lithium-ion batteries. 相似文献
194.
Barannikov Vladimir P. Guseynov Sabir S. Vyugin Anatoliy I. 《Journal of Thermal Analysis and Calorimetry》2009,95(2):547-552
The specific and non-specific interactions of twelve activated carbon cloth samples prepared from commercial cotton fabric,
and that present different activation degrees are studied through the determination of immersion enthalpies in CCl4 and H2O, and in aqueous solutions of NaOH and HCl.
The immersion enthalpies found for the solvents CCl4 and H2O are in a range of 5.49–45.84 and 1.77–7.76 J g−1, respectively. The enthalpic values for the materials in aqueous solutions of NaOH and HCl, allow characterizing the chemical
surface of these materials, which are in a range of 6.63 and 21.49 J g−1, finding through them important relations in company with other characterizing techniques used in the study of these materials. 相似文献
195.
We propose a method to improve the resolution of near-field optical system with a solid immersion lens by using a multiphase level Fresnel zone plate. The analyses are based on scalar angular spectrum theory. The results show that the multiphase Fresnel zone plate can not only decrease the spot size but also decrease the sidelobe intensity and enhance greatly the diffractive efficiency compared with annular amplitude filter or binary 2-, 3-, 4-zone phase filter. 相似文献
196.
Paweł Witowicz 《数学学报(英文版)》2010,26(2):345-352
This work gives a classification theorem for affine immersions with planar geodesics in the case where the codimension is maximal. Vrancken classified parallel affine immersions in this case and obtained, among others, generalized Veronese submanifolds. In this work it is shown that the immersions with planar geodesics are the same as the parallel ones in the considered case. A geometric interpretation of parallel immersions is also given: The affine immersions with pointwise planar normal sections (with respect to the equiaffine transversal bundle) are parallel. This result is verified for surfaces in R4 and for immersions with the maximal codimension. 相似文献
197.
Ramachandra Rao Jelena Mitic Alexandre Serov Rainer A. Leitgeb Theo Lasser 《Optics Communications》2007,271(2):462-469
The solid immersion lens (SIL) as a tool for increasing the field confinement as well as providing optimal performance by aberration compensation in a confocal fluorescence correlation spectroscopy (FCS) system is illustrated here. Using Zernike polynomials we show that aberration compensation and the resultant pre-shaping of the incident wavefront enables near diffraction-limited performance. This is explained based on vectorial computations for high apertures in the Debye approximation. The obtained axial resolution parameters are compared with the obtained diffusion times in a SIL-FCS experiment for measurements in solutions done at the single molecule level. 相似文献
198.
We define and discuss totally real and pseudoholomorphic immersions of real surfaces in a 4-manifold which, instead of an almost complex structure, carries only a framed spinc-structure, that is, a spinc-structure with a fixed generic section of its positive half-spinor bundle. In particular, we describe all pseudoholomorphic immersions of closed surfaces in the 4-sphere with a standard framed spin structure. 相似文献
199.
We describe a general construction of manufacturing new spherical minimal immersions between round spheres out of old ones. The new immersions have higher domain dimension and degree and the construction has a precise control on the codimension. Applied to classified and recent examples, the construction gives an abundance of new spherical minimal immersions with prescribed codimensions.Mathematics Subject Classifications (2000). 53C42 相似文献
200.
We characterize – by describing in local coordinates their sections – the transversal bundles which on the complex hypersurface with type number 1 induce locally symmetric connections. 相似文献