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771.
Analysis of a combined tip-tilt and deformable mirror 总被引:1,自引:0,他引:1
A deformable mirror mounted on a two-axis tilt platform can provide wavefront compensation at a single location in an adaptive optics system, resulting in a significant reduction in the number of optical components in the system and in a simplification of the alignment. However, the moment of inertia of a deformable mirror is significantly different from that of the monolithic mirror commonly mounted on a tilt platform. We report on what are to our knowledge the first experimental results of mounting a microelectromechanical deformable mirror onto a fast steering platform and the first observation that at low operating frequencies high-order deformation of the deformable mirror membrane was not recorded. 相似文献
772.
An affinity liquid chromatography (LC) method for the determination of bovine immunoglobulin G (IgG), using protein G coupled to an agarose support, was modified to permit the quantification of IgG in colostrum-based powders. Sample preparation included pH adjustment to 4.6 to precipitate casein and denatured whey protein. The method was applied to a range of colostrum powders and was compared with the alternative independent methods of surface plasmon resonance immunoassay, radial immunodiffusion, and reversed-phase LC. The method was rapid, and performance parameters included a working range of 10-150 microg IgG and precision relative standard deviation values of <10%. 相似文献
773.
Treating CpCp*HfMe(OTf) (1) with LiSbH(dmp) results in formation of CpCp*HfMe(SbHdmp), which undergoes alpha-abstraction to liberate methane and generate CpCp*Hf=Sb(dmp), which is thermally unstable but can be trapped with PMe(3) or 2-butyne to give CpCp*Hf(PMe(3))=Sb(dmp) (2) and CpCp*Hf[eta(2)-Sb,C:Sb(dmp)C(Me)=C(Me)] (3), respectively. 相似文献
774.
McNaughton D Robertson EG 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(3-4):1000-1002
We show that two of the three bands assigned to SPCN are assignable to cyanogen and that the bands assigned to SPCl are done so in error, with the 712 cm(-1) band in the spectrum of Allaf and Odeh assignable to HCN. There is no evidence for either ClPS or SPCN in the spectra shown. Finally low resolution IR spectroscopy by itself, whilst useful in assisting in the identification of pyrolysis products does not provide unambiguous identification and requires support by rigorous computation, band modelling and correct use of the literature. None of these are evidenced in the present paper of Allaf and Odeh nor indeed in the work that was the subject of our previous criticism and re-analysis. 相似文献
775.
776.
777.
Sakurai S Nishino H Futaba DN Yasuda S Yamada T Maigne A Matsuo Y Nakamura E Yumura M Hata K 《Journal of the American Chemical Society》2012,134(4):2148-2153
Here we show that essentially any Fe compounds spanning Fe salts, nanoparticles, and buckyferrocene could serve as catalysts for single-walled carbon nanotube (SWNT) forest growth when supported on AlO(x) and annealed in hydrogen. This observation was explained by subsurface diffusion of Fe atoms into the AlO(x) support induced by hydrogen annealing where most of the deposited Fe left the surface and the remaining Fe atoms reconfigured into small nanoparticles suitable for SWNT growth. Interestingly, the average diameters of the SWNTs grown from all iron compounds studied were nearly identical (2.8-3.1 nm). We interpret that the offsetting effects of Ostwald ripening and subsurface diffusion resulted in the ability to grow SWNT forests with similar average diameters regardless of the initial Fe catalyst. 相似文献
778.
The high-resolution (0.001 cm(-1)) spectrum of thiirane has been recorded at the far-infrared beamline at the Australian synchrotron between 760-400 cm(-1) and 170-10 cm(-1). Ro-vibrational transitions of the highly Coriolis coupled ν(5) (628.1 cm(-1)) and ν(15) (669.7 cm(-1)) fundamentals, as well as pure rotational far-IR transitions have been assigned, and rotational, centrifugal distortion, and Coriolis interaction parameters determined. ν(15) gains the vast majority of its intensity from an interesting Coriolis intensity stealing mechanism, which is also outlined. 相似文献
779.
Dietmar Seyferth Dennis C. Annarelli Steven C. Vick Don P. Duncan 《Journal of organometallic chemistry》1980,201(1):179-195
Hexamethylsilirane has been prepared by the action of magnesium on dimethyl-bis(α-bromoisopropyl)silane in tetrahydrofuran (THF) solution. It was found to be highly reactive toward atmospheric oxygen and moisture and to decompose when heated in solution at 60–75°C. Its decomposition results in the extrusion of dimethylsilylene which may add to the tetramethylethylene produced in the decomposition to regenerate the silirane, insert into the reactive SiC2 ring of the silirane to give octamethyl-1,2-disilacyclobutane or oligomerize to give (Me2Si)n oils.Dimethyldiisopropyl-, tetraisopropyl- and tert-butyltriisopropylsilane were prepared by catalytic hydrogenation of the corresponding isopropenylsilanes. Bromination of dimethyldiisopropylsilane at 65°C resulted in exclusive formation of dimethyl-bis(α-bromoisopropyl)silane. 相似文献
780.
A theory of cyclotron resonance lineshape due to electron-phonon interactions is presented on the basis of the projection operator method introduced by Argyres and Sigel. In addition to the extremely weak coupling scheme dealt with earlier, the moderately weak coupling scheme is included in the theory. The lineshape functions derived in the two schemes are similar to Lodder-Fujita's formula, and are reduced to Kawabata's formula in the elastic scattering approximation. 相似文献