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961.
Nanoparticulate flows occur in a wide range of natural phenomena and engineering applications and, hence,have attracted much attention. The purpose of the present paper is to provide a review of the research conducted over the last decade. The research covered relates to the Brownian coagulation of monodisperse and polydisperse particles, the Taylor-series expansion method of moment, and nanoparticle distributions due to coagulation in pipe and channel flow,jet flow, and the mixing layer and in the process of flame synthesis and deposition. 相似文献
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964.
针对无监督学习网络模型对于特定的映射空间,期望产生特定的影响具有一定的局限性,提出了有监督的可生长结构的动态结构模型;该模型将动态结构模型与径向基函数网络结构有机结合,采用的是需要时生长的自组织生长算法,通过插入新的神经元、改变竞争层神经元间的连接以及调整层与层的连接权值,达到模型输出的精度要求,有效地解决了在输入特定的网络数据时,能产生期望的输出;该模型应用于两轮平衡机器人的平衡控制,经过仿真实验表明,该动态结构模型能够实现对两轮平衡机器人的平衡控制,且有一定的抗干扰性和实用价值。 相似文献
965.
Hansen JO Huo P Martinez U Lira E Wei YY Streber R Laegsgaard E Hammer B Wendt S Besenbacher F 《Physical review letters》2011,107(13):136102
We have studied the interaction of ethanol with reduced TiO(2)(110)-(1 × 1) by high-resolution scanning tunneling microscopy (STM) measurements and density functional theory calculations. The STM data revealed direct evidence for the coexistence of molecularly and dissociatively adsorbed ethanol species on surface Ti sites. In addition, we found evidence for dissociation of ethanol at bridge-bonded O vacancies. The density functional theory calculations support these findings and rationalize the distinct diffusion behaviors of molecularly and dissociatively adsorbed ethanol species, as revealed in time-lapsed STM images. 相似文献
966.
SiC/W/Ir multilayer-coated grating for enhanced efficiency in 50-100 nm wavelength range in Seya-Namioka mount 总被引:1,自引:0,他引:1
A broadband [SiC/W/Ir](2) multilayer coating was deposited onto a diffraction grating to enhance the grating efficiency in the 50-100 nm wavelength range in a Seya-Namioka mount. The holographic ion-beam etched grating had a laminar profile with 1200 lines/mm. The coating was designed by using the subquarterwave multilayer theory. The measurement results show that the efficiency in the -1st diffraction order is greater than 9.3% throughout the wavelength range of 50-100 nm, which is obviously higher than that of single-layer gratings with SiC, Ir, or Au coatings. 相似文献
967.
We derive a reconstruction algorithm for refraction-contrast computed tomography (CT) using dark-field imaging (DFI) optics, which can extract refraction information by a single shot, from the ray equation in geometrical optics. The proposed algorithm is similar to the convolution reconstruction technique widely used in conventional CT. Thus, this algorithm can be implemented simply while also being fast and stable. To demonstrate its validity, we constructed the imaging system based on DFI optics composed of a transmission Laue-type angular analyzer at the vertical wiggler beamline BL-14C in KEK and performed a preliminary imaging experiment using a physical phantom to successfully obtain the DFI-CT image using the proposed algorithm. 相似文献
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7-氨基-6-硝基苯并二氧化噁二唑(呋咱)的合成、结构表征与性能研究 总被引:1,自引:0,他引:1
自行设计了7-氨基-6-硝基苯并二氧化噁二唑(呋咱)(ANBDF)新的合成方法,以1,3,5-三硝基-2,4-二氯苯为原料,经过叠氮化、脱氮环化得到关键中间体6-硝基苯并二氧化嗯二唑(呋咱)(NBDOF),然后利用异常亲核取代反应(VNS)在苯环上引入氨基得到目标化合物ANBDF,总收率为51.0%.中间体和目标产物均通过元素分析、核磁共振、红外光谱等进行了结构表征.优化了VNS反应条件,确定了适宜的条件为:盐酸羟胺为VNS试剂,20~40℃下反应5 h,收率70%.NBDOF与ANBDF的性能对比表明:ANBDF分子中的氨基与硝基形成的氢键,使得分子结构更加紧密,密度增加,热稳定性相当,感度显著降低,爆速提高.实验发现ANBDF没有熔点,分解过程分两步进行. 相似文献
970.
Lira E Wendt S Huo P Hansen JØ Streber R Porsgaard S Wei Y Bechstein R Lægsgaard E Besenbacher F 《Journal of the American Chemical Society》2011,133(17):6529-6532
The role of bulk defects in the oxygen chemistry on reduced rutile TiO(2)(110)-(1 × 1) has been studied by means of temperature-programmed desorption spectroscopy and scanning tunneling microscopy measurements. Following O(2) adsorption at 130 K, the amount of O(2) desorbing at ~410 K initially increased with increasing density of surface oxygen vacancies but decreased after further reduction of the TiO(2)(110) crystal. We explain these results by withdrawal of excess charge (Ti(3+)) from the TiO(2)(110) lattice to oxygen species on the surface and by a reaction of Ti interstitials with O adatoms upon heating. Important consequences for the understanding of the O(2)-TiO(2) interaction are discussed. 相似文献