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171.
In this short note, we discuss a kind of splines which are associated with some linear differential operators. These Splines are called Hermite-Λ interpolating splines which may be regarded as a generalization of piecewise Hermite interpolations. The main result is: Let f (x)∈C4[a,b],τ(x) be the Hermite-Λ interpolating spline to f(x), if h is sufficiently small, then (?). 相似文献
172.
Clifford分析中奇异积分的Poincaré-Bertrand置换公式 总被引:3,自引:0,他引:3
借助于多元复分析的思想,本文证明了Cliford分析中奇异积分的Poincaré-Bertrand置换公式. 相似文献
173.
The n most vital links (or nodes) in a weighted network are those n links (nodes) whose removal from the network results in the greatest increase in shortest distance between two specified nodes. Preliminary results are presented for obtaining these entities. 相似文献
174.
In nonpolar solvents, the cyclic hexapeptide 2, which comprises alternating D-alpha-amino and D-alpha-aminoxy acids, adopts a C3-symmetric conformation with alternating eight (N--O turns)- and seven (gamma turns)-membered-ring hydrogen bonds. A series of anion-binding studies has suggested that 2 can function as an effective anion receptor that not only displays a high selectivity for chloride ions, but also the capability to extract chloride ions from aqueous solutions into organic phases. 相似文献
175.
Toyosaka Moriizumi Paulo Jose Abatti Seimei Sha 《Applied biochemistry and biotechnology》1993,38(3):203-212
A rhythmic, sustained, stable oscillation was reproducibly observed for a lipid membrane supported by a micropore of a thin membrane tip micropipet (TM pipet). The construction of the TM pipet was accomplished by implementing a microfabrication method that allowed the transference of a Si3N4 film with a hole from the Si substrate to the glass tube tip. The main part of the fabrication method is the sealing process: a mix between thermal and amodic bonding. The TM pipet fabrication is described in detail with emphasis on the thermal-anodic bonding process. In addition, a general account of the new device's main features, including various applications, is given. 相似文献
176.
177.
Lina Zhang Heqing Yang Junhu Ma Li Li Xuewen Wang Lihui Zhang Sha Tian Xinyue Wang 《Applied Physics A: Materials Science & Processing》2010,100(4):1061-1067
ZnO nanorods with a cone and different aspect ratios and short-and-fat ZnO microrods were synthesized via a hydrothermal reaction
of Zn with Zn(CH3COO)2 and H2O. The control over these ZnO nanocrystals with a wurtzite structure and different shapes was achieved by adjusting only the
reaction temperature and time. A possible kinetic mechanism was proposed to account for the growth of these ZnO nanocrystals
with different shapes. Photocatalytic activities of ZnO nanocrystals with distinctive shapes in the degradation of methyl
orange were investigated. The results indicate that the photocatalytic ability of the ZnO nanorods with a cone and different
aspect ratios is stronger than that of the short-and-fat microrods. 相似文献
178.
The histology and ultrastructure of the seminal vesicle, male accessory gland and the epididymis in Panorpa and Sinopanorpa were observed using light microscopy and scanning and transmission electron microscopy. The seminal vesicle consists of a mono-layered elongated columnar epithelium, which contains abundant electron-dense granules and secretory vesicles, and a small central lumen. In the apical region of the epithelium of the seminal vesicle, the intense secretory activity seems to be effected by means of merocrine mechanisms. The epithelium of the accessory gland is rich in rough endoplasmic reticulum and Golgi complex, and secretes seminal fluid into the lumen via both apocrine and merocrine mechanisms. The seminal vesicle is similar to the accessory gland in the epithelium structure and their secretory activity, mainly serving a secretory function rather than storing sperms. Instead, the sperms are stored in the epididymis, whose epithelium secretes nutrients into the large lumen by merocrine mechanisms. The secretory activity and function of the seminal vesicle are briefly discussed. 相似文献
179.
180.
Airy加速光束是近年来备受关注的一种新型无衍射光束. 它所具有的自由加速、无衍射及自恢复特性使其在光学微操纵、非线性光学、 电子加速等诸多领域显示出重要的应用价值. 因此, 如何方便高效地生成加速光束成为近年来的一个热点研究内容. 本文对Airy加速光束复振幅分布的空间振荡特性进行了分析, 建立了利用局域空间频率描述其加速特性的理论. 提出了利用零点坐标计算加速光束局域空间频率的方法, 通过非线性拟合给出了可以精确描述Airy光束局域空间频率的解析公式; 确定了加速光束的局域空间频率函数与加速轨迹之间的定量关系, 给出了由给定加速轨迹计算相应的局域空间频率以及加速光束的纯相位函数的一种简单计算方法. 将上述分析结果用于设计产生具有给定加速轨迹的加速光束所需的相位函数, 成功求出了能够产生圆弧形加速轨迹的新型加速光束的纯相位函数的解析表达式. 基于该相位函数设计的纯相位衍射光学元件的模拟衍射结果证明了上述方法的可行性.
关键词:
衍射光学
加速光束
局域空间频率 相似文献