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51.
A convenient synthetic procedure for preparing nickel carboxylated phthalocyanine is reported. Upon further hydroxylation, such metal phthalocyanine moieties are incorporated into several melamine-based polyester high-solids systems and the structure—property correlations are examined. Molecular level spectroscopic FTIR analysis and mechanical testing are correlated in an effort to establish structure—property relations in these coatings. It is found that the presence of metal phthalocyanine macrocycle as a cross-linking agent enhances such properties as adhesion, hardness, and impact resistance. © 1993 John Wiley & Sons, Inc. 相似文献
52.
Presents arguments crediting group therapy with the rise of eclecticism among psychologists. A 2-semester course for advanced doctoral candidates is described and its 5-yr history outlined. Items discussed include physical setup, course planning and conduct, prerequisites, observation (patient) group composition, recruitment and preparation, and therapist recruitment. Advantages of the method are presented. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Hecht B 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2004,362(1817):881-899
This paper reviews the recent progress in using single quantum systems, here mainly single fluorescent molecules, as local probes for nano-optical field distributions. We start by discussing the role of the absorption cross-section for the spatial resolution attainable in such experiments and its behaviour for different environmental conditions. It is shown that the spatial distribution of field components in a high-numerical aperture laser focus can be mapped with high precision using single fluorescent molecules embedded in a thin polymer film on glass. With this proof-of-principle experiment as a starting point, the possibility of mapping strongly confined and enhanced nano-optical fields close to material structures, e.g. sharp metal tips, is discussed. The mapping of the spatial distribution of the enhanced field at an etched gold tip using a single molecule is presented as an example. Energy transfer effects and quenching are identified as possible artefacts in this context. Finally, it is demonstrated that the local quenching at a sharp metal structure nevertheless can be exploited as a novel contrast mechanism for ultrahigh-resolution optical microscopy with single-molecule sensitivity. 相似文献
54.
This paper describes an experimental investigation of the mechanical behavior of a paper-filled-phenolic laminate widely used
in the electronics industry. Uniaxial tensile tests in three directions, sandwich-beam bending tests to determine the compressive
behavior, and cylindrical-punch punchability tests were conducted. Interesting phenomena observed included difference in tensile
and compressive behavior, consistent crack branching in tension, and strain mismatch during punching.
Based upon a thesis submitted by the first author in partial fulfillment of the requirements for the M.S. degreee in Mechanical
Engineering at the University of Oklahoma, December 1976. 相似文献
55.
CoAPO-5 molecular sieves have been synthesized with glycerol and water as solvent in order to maximize the degree of isomorphous substitution of Co2+ ions in the AFI framework. These CoAPO-5 molecular sieves have been characterized with X-ray diffraction, inductively coupled plasma-atomic emission spectroscopy, scanning electron microscopy, electron microprobe microanalysis, N2 sorption, and UV-visible-NIR-diffuse reflectance spectroscopy techniques. Optimum conditions for the synthesis of Co-rich single-phase and highly crystalline CoAPO-5 molecular sieves were obtained by varying the [Co]:[Al] ratio in the synthesis gel and the synthesis time. It will be shown that highly crystalline hexagonal single-phase CoAPO-5 crystals with a size between 3 and 10 microns and a substitution degree of about 13% can be obtained from a 0.7CoO.0.65Al2O3.1P2O5.1(C2H5)3N.40HOCH2CHOHCH2OH gel at 190 degrees C after 14 days of synthesis. This substitution degree is substantially higher than that for CoAPO-5 materials synthesized in the presence of water (i.e., about 7.5%). 相似文献
56.
3D shape metamorphosis based on T-spline level sets 总被引:1,自引:0,他引:1
We propose a new method for 3D shape metamorphosis, where the in-between objects are constructed by using T-spline scalar
functions. The use of T-spline level sets offers several advantages: First, it is convenient to handle complex topology changes
without the need of model parameterization. Second, the constructed objects are smooth (C2 in our case). Third, high quality meshes can be easily obtained by using the marching triangulation method. Fourth, the distribution
of the degrees of freedom can be adapted to the geometry of the object.
Given one source object and one target object, we firstly find a global coordinate transformation to approximately align the
two objects. The T-spline control grid is adaptively generated according to the geometry of the aligned objects, and the initial
T-spline level set is found by approximating the signed distance function of the source object. Then we use an evolution process,
which is governed by a combination of the signed distance function of the target object and a curvature-dependent speed function,
to deform the T-spline level set until it converges to the target shape. Additional intermediate objects are inserted at the
beginning/end of the sequence of generated T-spline level sets, by gradually projecting the source/target object to the initial/final
T-spline level set. A fully automatic algorithm is developed for the above procedures. Experimental results are presented
to demonstrate the effectiveness of our method. 相似文献
57.
Berg Cynthia A.; Smith Timothy W.; Ko Kelly J.; Beveridge Ryan M.; Story Paul; Henry Nancy J. M.; Florsheim Paul; Pearce Gale; Uchino Bert N.; Skinner Michelle A.; Glazer Kelly 《Canadian Metallurgical Quarterly》2007,22(4):718
Reports an error in "Task control and cognitive abilities of self and spouse in collaboration in middle-aged and older couples" by Cynthia A. Berg, Timothy W. Smith, Kelly J. Ko, Nancy J. M. Henry, Paul Florsheim, Gale Pearce, Bert N. Uchino, Michelle A. Skinner, Ryan M. Beveridge, Nathan Story and Kelly Glazer (Psychology and Aging, 2007[Sep], Vol 22[3], 420-427). Due to an editing mistake, the order of authorship was incorrect. The correct order is as follows: Berg, Smith, Ko, Beveridge, Story, Henry, Florsheim, Pearce, Uchino, Skinner, & Glazer. (The following abstract of the original article appeared in record 2007-13103-002.) Collaborative problem solving may be used by older couples to optimize cognitive functioning, with some suggestion that older couples exhibit greater collaborative expertise. The study explored age differences in 2 aspects of collaborative expertise: spouses' knowledge of their own and their spouse's cognitive abilities and the ability to fit task control to these cognitive abilities. The participants were 300 middle-aged and older couples who completed a hypothetical errand task. The interactions were coded for control asserted by husbands and wives. Fluid intelligence was assessed, and spouses rated their own and their spouse's cognitive abilities. The results revealed no age differences in couple expertise, either in the ability to predict their own and their spouse's cognitive abilities or in the ability to fit task control to abilities. However, gender differences were found. Women fit task control to their own and their spouse's cognitive abilities; men only fit task control to their spouse's cognitive abilities. For women only, the fit between control and abilities was associated with better performance. The results indicate no age differences in couple expertise but point to gender as a factor in optimal collaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Levin R. V. Nevedomskii V. N. Pushnyi B. V. Bert N. A. Mizerov M. N. 《Technical Physics Letters》2016,42(1):96-98
The possibility of fabricating InAs/GaSb strained-layer superlattices by metalorganic chemical vapor deposition has been experimentally demonstrated. The results of transmission electron microscopy and photoluminescence spectroscopy investigations showed that the obtained structures comprise an InAs?GaSb superlattice on a GaSb substrate consisting of 2-nm-thick InAs and 3.3-nm-thick GaSb layers.
相似文献59.
60.
Pradip Mainali Gauthier Lafruit Qiong Yang Bert Geelen Luc Van Gool Rudy Lauwereins 《International Journal of Computer Vision》2013,104(2):172-197
We present a new method to extract scale-invariant features from an image by using a Cosine Modulated Gaussian (CM-Gaussian) filter. Its balanced scale-space atom with minimal spread in scale and space leads to an outstanding scale-invariant feature detection quality, albeit at reduced planar rotational invariance. Both sharp and distributed features like corners and blobs are reliably detected, irrespective of various image artifacts and camera parameter variations, except for planar rotation. The CM-Gaussian filters are approximated with the sum of exponentials as a single, fixed-length filter and equal approximation error over all scales, providing constant-time, low-cost image filtering implementations. The approximation error of the corresponding digital signal processing is below the noise threshold. It is scalable with the filter order, providing many quality-complexity trade-off working points. We validate the efficiency of the proposed feature detection algorithm on image registration applications over a wide range of testbench conditions. 相似文献