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111.
Optical coatings offer a solution to the problem of damage to paintings, caused by ultraviolet and infrared radiation, by cutting radiation wavelengths outside the visible range. Simultaneously, these coatings can enhance an observer's viewing of the paintings by reducing the reflections from ordinary glass panes. All these functions should be performed by the same coating. The design of such a coating, as well as the evaluation of existing products, requires the definition of an appropriate merit function in which coating absorption, high transparency, and color rendering are combined. 相似文献
112.
Holden Ronald R.; Wasylkiw Louise; Starzyk Katherine B.; Book Angela S.; Edwards Melanie J. 《Canadian Metallurgical Quarterly》2006,38(1):24
Four studies investigated the dimensionality of the NEO Five-Factor Inventory (NEO-FFI; P. T. Costa & R. R. McCrae, 1992). In Study 1, four inferential dimensions and four clusters represented the NEO-FFI when 114 undergraduates freely sorted items into categories. Construct validity for four item-clusters derived from the inferential space was obtained in Study 2 based on self-report with 304 undergraduates. Study 3 validated these inferential clusters using self and peer reports for 420 undergraduates. Study 4 validated the cluster scales for predicting quality of life and significant social and cultural behaviours for 110 undergraduates. Implications for implicit personality theory, the number of dimensions issue in personality, and test construction are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Cowan Nelson; Naveh-Benjamin Moshe; Kilb Angela; Saults J. Scott 《Canadian Metallurgical Quarterly》2006,42(6):1089
We asked whether the ability to keep in working memory the binding between a visual object and its spatial location changes with development across the life span more than memory for item information. Paired arrays of colored squares were identical or differed in the color of one square, and in the latter case, the changed color was unique on that trial (item change) or was duplicated elsewhere in the array (color-location binding change). Children (8-10 and 11-12 years old) and older adults (65-85 years old) showed deficits relative to young adults. These were only partly simulated by dividing attention in young adults. The older adults had an additional deficiency, specifically in binding information, which was evident only when item- and binding-change trials were mixed together. In that situation, the older adults often overlooked the more subtle, binding-type changes. Some working memory processes related to binding undergo life-span development in an inverted-U shape, whereas other, bias- and salience-related processes that influence the use of binding information seem to develop monotonically. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
It is widely accepted that the successful adoption of an information system depends to a great extent on users' perceptions of the information system. It follows then that an understanding of users' cognitive frames should be a key factor in managing the adoption of information systems. To reach such an understanding is not an easy task as cognitive frames are dynamic phenomena. For example, what an individual perceives as ‘ease of use’ and ‘usefulness’ may depend not only on intrinsic qualities of the information system but also on the changing contexts in which the information system is evaluated. This work argues that the management of information systems' adoption is a social and political process in which stakeholders frame and reframe their perceptions of an information system. A case study carried out in a European bank illustrates how the Bank's technical team influenced users' technological frames, including those of senior management in order to ensure a smooth implementation process. In conclusion, the paper introduces a set of theoretical propositions relating to the social and political processes that occur during information systems adoption. 相似文献
115.
116.
Angela M. Gyurko Gregory E. Vignoul John K. Tien Juan M. Sanchez 《Metallurgical and Materials Transactions A》1992,23(11):3073-3076
Engineering, University of Texas at Austin, Austin, TX 78712 While much of the high-temperature intermetallics research has
centered around Ni3Al and other aluminum-based systems, the present study focuses on the Engel-Brewer Ll2 intermetallic Ir3Zr, which has a melting temperature approaching that of ceramics (2280 °C). Due to limited material availability, the technique
of microindentation was used to study both the temperature and time dependence of strength. Because of the widely held belief
that certain mechanical properties of intermetallics scale roughly with temperature, Ir3Zr was expected to exhibit high strength. The microhardness was observed to vary from 225 MPa at room temperature to 75 MPa
at 1400 °C, which is significantly lower than the behavior of Ni3Al. The activation energy for creep was determined to be 467 kJ/mole, and the stress exponent was found to be 18.2. The ordering
energy of this system was calculated to be 0.114 eV. If it can be assumed that high ordering energy correlates to a high antiphase
boundary (APB) energy, then the behavior of this system is consistent with a model that predicts highly glissile dislocation
cores. 相似文献
117.
In response to K. B. Little's (1973) article on the Central Office organization of the American Psychological Association, Ginorio questions whether the distribution of women in the governing body is representative of practices proposed in the Affirmative Action plan of 1973. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Ganz PJ Bauer MD Sun Y Fieno AM Grant RA Correa PE Laskowski M Saunders CW 《Protein engineering, design & selection : PEDS》2004,17(4):333-339
Protein protease inhibitors could potentially be used to stabilize proteases in commercial products such as liquid laundry detergents. However, many protein protease inhibitors are susceptible to hydrolysis inflicted by the protease. We have engineered Streptomyces subtilisin inhibitor (SSI) to resist proteolysis by adding an interchain disulfide bond and removing a subtilisin cleavage site at leucine 63. When these stabilizing changes were combined with changes to optimize the affinity for subtilisin, the resulting inhibitor provided complete protease stability for at least 5 months at 31 degrees C in a subtilisin-containing liquid laundry detergent and allowed full recovery of the subtilisin activity upon the dilution that occurs in a North American washing machine. 相似文献
119.
120.
Pignatello R Spadaro D Vandelli MA Forni F Puglisi G 《Drug development and industrial pharmacy》2004,30(3):277-288
The present study is a preliminary exploration of the affinity between a carboxylic model drug, the nonsteroidal antiinflammatory agent ibuprofen (IBU) and Eudragit RL100 (RL) polymer. Due to the presence of a variable amount of quaternary ammonium groups in this matrix, physical and chemical interaction with the carboxylic drug can occur, which reinforces its scant mechanical dispersion in the polymer network and can ultimately affect its release profile in vitro and in vivo. To study these aspects, IBU was mixed at increasing weight ratios and in different chemical forms (free acid, sodium salt, and n-butyl ester), to investigate further the role of the carboxylic group in the interaction with the RL polymer. Therefore, IBU-RL solid dispersions (coevaporates) were obtained and fully characterized in the solid state through spectroscopic, calorimetric, and x-ray diffractometric analyses. The in vitro release pattern of the drug, in the different chemical states, was studied for the coevaporates, compared with drug-RL physical mixtures, along with drug adsorption profiles from aqueous solutions on the surface of the polymer granules. 相似文献