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141.
Bistatic scattering by arbitrarily shaped objects with rough surface at optical and infrared frequencies 总被引:2,自引:0,他引:2
The scattering cross sections for arbitrarily shaped dielectric objects with rough surface are determined for optical and infrared frequencies using the Kirchhoff approximation. The formula of the coherent scattering cross section is derived, and numerical method of incoherent scattering cross section is given. As a specific example, the infrared laser scattering cross sections of rough spheres are calculated at 1.06 m. 相似文献
142.
Crystal of Yb3+-doped Ba3Gd(BO3)3 has been grown by the Czochralski method. The spectroscopic characterizations have been investigated at room temperature. The Yb3+:Ba3Gd(BO3)3 crystal exhibits broad absorption at 976nm with FWHM of 7nm and large overall spitting of 2F7/2 manifold (823cm-1). The absorption and emission cross sections are 5.09×10-21cm2 at 976nm and 0.97×10-21cm2 at 1040nm,respectively. The fluorescence lifetime is 2.84 ms. 相似文献
143.
Jorge Pavez Maritza Páez Armelle Ringuedé Fethi Bedioui José H. Zagal 《Journal of Solid State Electrochemistry》2005,9(1):21-29
We studied the electrocatalytic activity of cobalt tetra-aminophthalocyanine (CoTAPc) for the reduction of molecular oxygen (O2) on adsorbed monomeric and on electropolymerized films of different thicknesses on glassy carbon (GC) electrode. The polymeric films, denoted poly-CoTAPc, were first characterized by electrochemical impedance spectroscopy and it appears that the types of phenomena revealed to be occurring depend less on the film thickness in basic than in acid media. For O2 reduction, the results showed that poly-CoTAPc is more active than the monomeric CoTAPc adsorbed on GC. Indeed, rotating ring-disk electrode data showed that polymeric CoTAPc promotes the four-electron reduction of O2 to water in parallel to a two-electron reduction to give peroxide. On monomeric and thin films of poly-CoTAPc, a two-electron reduction mechanism predominates. In basic media the activity increases very slightly with thickness, whereas in acid media this increase is more pronounced. This parallels the observed behavior revealed by electrochemical impedance spectroscopy. 相似文献
144.
145.
The nickel–iron alloy electrodeposition is affected by a superimposed magnetic field. Some previous papers [Msellak et al.,
Magnetohydrodynamics, 39:487–493, 2003 and Msellak et al., J Magn Magn Mat, 281:295–304, 2004] have exhibited some dramatic changes in iron amount and morphology of these deposits. As it is usual for a magnetic field
up to 1 T, no charge transfer effect can be expected, and the observed modifications can be explained by the magnetohydrodynamic
convection that controls the iron species flux during the electrochemical reaction. By electrochemical impedance spectroscopy
and physical investigations (scanning electron microscopy, X-ray diffraction, and inductively coupled plasma), the reduction
process is analyzed, the characteristic parameters of the mechanism are determined, and the magnetic field effects can be
quantified.
Contribution to special issue on “Magnetic field effects in Electrochemistry”. 相似文献
146.
Masaki Shimizu Prof. Dr. Takuya Kurahashi Dr. Katsuhiro Shimono Dr. Kei Tanaka Ikuhiro Nagao Shin‐ichi Kiyomoto Tamejiro Hiyama Prof. Dr. 《化学:亚洲杂志》2007,2(11):1400-1408
Treatment of 1,1‐bis(pinacolatoboryl)ethene with an excess of 1‐bromo‐1‐lithioethene gave 2,3‐bis(pinacolatoboryl)‐1,3‐butadiene in high yield. Palladium‐catalyzed cross‐coupling of the resulting diborylbutadiene with aryl iodides took place smoothly in the presence of a catalytic amount of Pd(OAc)2/PPh3 and aqueous KOH to give 2,3‐diaryl‐1,3‐butadienes in good yields. The coupling reaction with commercially available 4‐acetoxyphenylmethyl chloride under the same conditions followed by hydrolysis of the acetyl groups gave anolignan B in a one‐pot manner. A variety of [3]‐ to [6]dendralenes were synthesized by palladium‐catalyzed coupling of the diene or 1,1‐bis(pinacolato)borylethene with alkenyl or dienyl halides, respectively, in good yields. 相似文献
147.
在石英单晶表面制成矩矩截面毛细管柱中进行电泳实验。由于矩形柱比圆形柱有更大散热侧面积且石英单晶的导热性能远无于熔融石英,所以可施加较高的场强,不仅提高了柱效,而且缩矩了分离时间。两相交的通道之间形成自然连接,可实现二维分离,并消除死体积。 相似文献
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