Infrared Spectra and Structures for Group 4 Dihydroxide and Tetrahydroxide Molecules
作者:Xuefeng Wang、Lester Andrews
DOI:10.1021/jp054482i
日期:2005.12.1
atoms react with H(2)O(2) molecules and with H(2) + O(2) mixtures to form M(OH)(2) and M(OH)(4) molecules, which are trapped in solid argon and identified from isotopic shifts in the infraredspectra. Electronic structure calculations at the MP2 level converge to almost linear M(OH)(2) and tetrahedral M(OH)(4) molecules and predict vibrational frequencies for mixed isotopic molecules of lower symmetry
Infrared Spectrum and Structure of the Hf(OH)<sub>4</sub> Molecule
作者:Xuefeng Wang、Lester Andrews
DOI:10.1021/ic050614a
日期:2005.10.1
Laser-ablated Hf atoms react with H2O2 and with H2 + O2 mixtures in solidargon to form the Hf(OH)2 and Hf(OH)4 molecules, which are identified from the effect of isotopic substitution on the matrix infraredspectra. Electronic structure calculations at the MP2 level varying all bond lengths and angles converge to nearly linear and tetrahedral molecules, respectively, and predict frequencies for these
An axially contractable actuator (11) has an inflatable bladder (14) which unfolds on filling with pressurized fluid to contract axially as the volume of contained pressurized fluid is increased. The wall of the bladder is formed by a series of adjoining polyhedral protrusions (15) extending outwardly from the actuator axis, each protrusion having four or more sides and adjoining protrusions being joined at their bases to form folds or seams along substantially straight lines. Each protrusion additionally is foldable along another flexible fold or seam (55) of the protrusion wall in a theoretical plane dividing the respective protrusion into two parts, the protrusions unfolding from an axially extended condition of the actuator, in which they enclose a reduced volume, to an axially contracted condition in which they enclose a larger volume. Optionally, axially aligned end connectors (30) are provided at the bladder ends, and these are joined by linked cables (20) embracing the protrusions along fold lines (55) at the protrusion bases (44).
A materials processing unit incorporating three stage processing. The material to be processed is passed through a breaker unit (19) which breaks the material down to a consistent size for processing by a pulveriser unit (20) which further breaks down the material before it is transferred to a container (13) for compacting by ram (27) and blade (28). The material may be transferred to the container (13) by auger screws (25, 26) or a vacuum system comprising a fan (34) for reducing the pressure within the container (13) and causing the material to be sucked through duct (40) into the container (13). The unit may be mounted on a wheeled vehicle (12) and used to process a variety of materials from garbage to fruit.
The raman spectra and X-ray powder diffraction data of stabilized hafnia phases
作者:M.A. Krebs、R.L. Snyder、R.A. Condrate
DOI:10.1016/0025-5408(83)90151-4
日期:1983.9
phase apparently possessing tetragonal distortion with increasing dopant concentration. In contrast to the results for pure zirconia, there was no evidence in the Raman spectra or powder X-ray diffraction patterns to indicate the formation of a small particle size-stabilized tetragonal hafnia phase when X-ray amorphous hafnium hydroxide was heated at 425–600°C.
摘要 测量了 Y2O3 掺杂铪的各种成分的拉曼光谱和 X 射线粉末衍射数据,并根据稳定的二氧化铪相的生长进行解释,该相随着掺杂浓度的增加而明显具有四方畸变。与纯氧化锆的结果相反,在拉曼光谱或粉末 X 射线衍射图中没有证据表明当 X 射线无定形氢氧化铪在 425 ℃加热时形成小粒径稳定的四方铪相。 600°C。