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81.
The application of focused ion beam (FIB) machining in several technologies aimed at microstructure fabrication is presented. These emergent applications include the production of micromilling tools for machining of metals and the production of microsurgical tools. An example of the use of microsurgical manipulators in a circulatory system measurement is presented. The steps needed to transform the laboratory fabrication of these tools and manipulators into a routine FIB production process are discussed. The ion milling of three-dimensional cavities by the exact solution of a mathematical model of the FIB deflection is demonstrated. A good agreement between the model calculation and the ion beam control has been obtained for parabolic and cosine cross-section features with planes of symmetry. 相似文献
82.
H. Selig W.A. Sunder M.J. Vasile F.A. Stevie P.K. Gallagher L.B. Ebert 《Journal of fluorine chemistry》1978,12(5):397-412
IF7 intercalates into graphite accompanied by the partial fluorination of the graphite host. The intercalated species was identified as IF5 by IR and 19F nmr spectroscopies. Mass spectrometric analyses of the gases evolved from the intercalate showed only IF5 and fluorocarbons. Iodine pentafluoride intercalates only in the presence of HF, yielding a compound with the stoichiometry C8IF5 and no fluorination of the graphite host. Careful elimination of even traces of HF resulted in no intercalation. Evolved gas analysis showed that the only species recovered from the intercalation was IF5. The remaining interhalogens, ClF5, ClF3, BrF5 and BrF3 all intercalate into graphite with extensive fluorination of the lattice. In the case of these four compounds, the intercalate proved to be more difficult to characterize, e.g. stoichiometry was often variable, and 19F nmr yielded resonances that did not agree with any known halogen fluorides. Thermal decomposition of these intercalates showed little or no gas evolution until relatively high temperatures were reached, whereupon Cl2 or Br2 was evolved, followed by fluorocarbons. 相似文献
83.
84.
A comparison has been made between (a) mixtures of the binary copolymers of acrylonitrile with vinyl acetate and with α-methyl styrene and (b) the ternary copolymer. The two products have been characterized for thermal and mechanical behaviour. For each pair of copolymers, a study has been made of compatibility in establishing the type of mixture and the variation of properties with composition. 相似文献
85.
K. Venkateswarlu F.A.Sc. S. Jagatheesan K. V. Rajalakshmi 《Proceedings Mathematical Sciences》1963,58(6):373-380
The harmonic wave numbers for HCOF and DCOF have been calculated using the observed fundamentals and the force constants have been evaluated on the basis of the general quadratic and Urey-Bradley force fields. The out-of-plane fundamental in HCOF, which has not been reported so far, is calculated. The thermodynamic properties of HCOF and DCOF have been calculated for fourteen temperatures ranging from 200° K. to 1500° K. for the ideal gaseous state at one atmosphere pressure and for a rigid rotor, harmonic oscillator approximation. 相似文献
86.
87.
The reaction of hexachloropropene with hydroxy-coumarins and chromones has been utilized to synthesise dichloro-benzodipyrandiones. The structures of the latter have been deduced from their spectral-analytical data. The reaction with 4-hydroxy-coumarin derivatives affords dichloropyrano-benzpyrandiones. 相似文献
88.
A method is given to determine whether or not the distribution functions describing the two spin measurements in the spin-s Einstein-Podolsky-Rosen experiment are compatible with the existence of distributions describing three spin measurements (not all of which can actually be performed). When applied to the spin-1/2 case the method gives the results of Wigner, or of Clauser, Holt, Horne, and Shimony, depending on whether or not the two-spin distributions are assumed to have the forms given by the quantum theory. Generalizations of the conditions of Wigner or of Clauser et al. to the spin-1 case are explicitly calculated. The spin-3/2 case is examined in some simple geometries to show that an apparently monotonic trend toward local realism as s increases from1/2 to1 is, in fact, violated when s increases from1 to3/2. The analysis is based on a novel representation of the modulus squared of a rotation matrix element. The structure of that matrix element responsible for the restoration of local realism in the classical (large s) limit is identified, but a rigorous treatment of the classical limit is not attempted. The higher-spin results are significantly stronger than those given by Mermin's spin-s Bell inequality. 相似文献
89.
90.
A normal co-ordinate treatment has been carried out to calculate the force constants of BH3CO and BD3CO molecules, on the basis of a Urey-Bradley potential force field. 相似文献