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101.
Measuring Software Screen Complexity: Relating Eye Tracking,Emotional Valence,and Subjective Ratings
Joseph H. Goldberg 《International journal of human-computer interaction》2014,30(7):518-532
Enterprise software pages, routinely used to conduct a variety of business-relevant tasks, must be clear and nonconfusing to experienced end users. A study was conducted to consider the impact of several page design factors (background gradient, font, and font size) on perceived ratings of page clarity, completion time, emotional valence (EV) from video, and several eye-tracking parameters. Twenty professional managers each completed 25 tasks on enterprise web pages designed with specific combinations of these factors. Highly rated pages had Tahoma and Larger fonts, compared to Calibri and Smaller fonts. The Gradient background did not influence ratings but did increase the search area and completion time. Although EV was not a sensitive measure across tasks, it was influenced by font differences in the first few seconds of page presentation. Overall, the use of background gradient was not supported, but both Tahoma and Larger fonts were supported for these enterprise pages. 相似文献
102.
Joseph Berger 《Polymer》1984,25(11):1629-1632
New light-sensitive polymers were prepared by modification of four different elastomers with 4-(N-dimethylmaleimido)-benzenesulphenyl chloride (DMI-BSCI). Polydienes modified by DMI-BSCI form block copolymers. These polymers show a strong increase of the glass transition temperature Tg whereby the Tg increase of modified poly(octenamer) is much smaller. Higher modified polydienes have two Tg. Modified poly(octenamers) show a melting temperature dependence Tm on the content of trans double bonds which is characteristic of statistical copolymers. The ratio of rate constants with which trans- and cis-structures in poly(octenamer) are occupied by DMI-BSCI, is 相似文献
103.
John C. Lynch Jonathan S. Green Paul K. Hovsepian Kathleen L. Reilly Joseph A. Short 《Journal of Automated Methods and Management in Chemistry》1994,16(4):131-133
Laboratory robotics has been firmly established in many non-QC
laboratories as a valuable tool for automating pharmaceutical
dosage form analysis. Often a single project or product line is used
to justify an initial robot purchase thus introducing robotics to the
laboratory for the first time. However, to gain widespread acceptance
within the laboratory and to justify further investment in robotics,
existing robots must be used to develop analyses for existing manual
methods as well as new projects beyond the scope off the original
purchase justification. The Automation Development Group in
Analytical Research and Development is a team of analysts
primarily devoted to developing new methods and adapting existing
methods for the robot. This team approach developed the expertise
and synergy necessary to significantly expand the contribution of
robotics to automation in the authors'' laboratory. 相似文献
104.
Thomas F. Derosa Benjamin J. Kaufman Rodney L.-D. Sung Joseph M. Russo 《应用聚合物科学杂志》1994,51(7):1339-1346
Perfluorobutyl-1,1,2-tri-H-1-hexene and perfluoroalkyl methacrylate have been solubilized in lubricating oil by single-step free radically grafting onto poly(ethylene-co-propylene). Perfluoroalkyl-1,1,2,2-tetra-H-ethanol and perfluoropolyether carboxylic acid were solubilized by condensing with poly[(ethylene-co-propylene)-g-glycidyl methacrylate], generating the corresponding perfluoroalkyl ether or ester, respectively. Solubilization of 1,1,2,2-tetra-H-ethanol was also achieved by condensing with poly[(ethylene-co-propylene)-g-2-isocyanoethyl methacrylate] to the corresponding perfluoroalkyl urethane. Scar diameter reductions ranged from 9.4 to 58% using perfluoro-modified graft copolymers as determined using the Four Ball Wear Test, although optimum reductions were obtained using perfluoroalkyl urethane-modified graft copolymers. Moreover, a semiquantitative correlation of scar reductions and thermal instability was determined. Sequence VI engine testing of perfluoroalkyl urethane graft copolymers containing pendant perfluoroalkyl chain lengths of 8.2 and 7.2 had an Equivalent Fuel Economy Index of 4.33 and 4.27, respectively. © 1994 John Wiley & Sons, Inc. 相似文献
105.
Oyster tissue contained 2.4% lipid, 0.14 μmole aldehyde per milligram lipid and at least 10 μg phosphorous per milligram lipid.
The neutral lipid represented 58%, the glycolipid 6%, and the polar lipid 36% of the total lipid recovered after silicic acid
column chromatography. Aldehydes were found in all fractions, but the presence of plasmalogen was verified in only the neutral
and polar lipid fractions. At least 68% of the plasmalogen in oyster lipid was found in the polar lipid fraction. At least
13% of the phosphorous in oyster lipids was present as phosphonolipid. The distribution of phosphate and phosphonate lipids
was: diacyl phospholipid 38.1%, plasmalogen phospholipid 21.8%, sphingophosphonolipid 13.5%, glyceryl ether phospholipid 8.3%,
sphingophospholipid 6.9%, plasmalogen phosphonolipid 6.4%, diacyl phosphonolipid 2.6%, and glyceryl ether phosphonolipid 2.4%.
When the per cent of phosphorous as phosphonolipid within the plasmalogen and glyceryl ether classes was calculated, similar
values were obtained. These results support the hypothesis that there is a product precursor relationship between these two
classes of lipids.
Some of the data taken from a thesis to be submitted to the Graduate School, University of Maryland, by Leslye Johnson in
partial fulfillment of the requirements for the M.S. degree in biochemistry. 相似文献
106.
Melanie T. Schaal Ashley Y. Metcalf Joseph H. Montoya J. Paul Wilkinson Carol C. Stork Christopher T. Williams John R. Monnier 《Catalysis Today》2007,123(1-4):142-150
Electroless deposition has been used to prepare Cu–Pd/SiO2 bimetallic catalysts wherein initial Cu coverages are limited only to the pre-existing Pd surface. Cu loading on the Pd surface can be systematically varied by modification of deposition kinetic parameters. In this case deposition time was used as the kinetic variable for the preparation of a series of Cu–Pd catalysts. These materials have been characterized using atomic absorption, CO chemisorption, and FT-IR (adsorption of CO), and then evaluated for the hydrogenation of 3,4-epoxy-1-butene, a functionalized olefin having many potential reaction pathways. Catalyst performance and characterization results suggest that Cu is not distributed in a monodisperse manner on the Pd surface, indicating the existence of autocatalytic deposition of Cu on Cu sites. The FT-IR results suggest that although CO adsorption on all sites is suppressed by Cu addition, initial Cu deposition occurs more readily on certain sites. The bimetallic Cu–Pd sites that are formed exhibit unusually high activity for EpB conversion and formation of unsaturated alcohols and aldehydes. This bimetallic effect on catalyst activity and selectivity is best explained, not by the existence of either ligand or ensemble effects, but rather by the bifunctional nature of the Cu–Pd sites present on the surface of these catalysts. 相似文献
107.
Secretions from the metathoracic glands (MTG) of the black locust bug, Lopidea robiniae (Uhler) (Heteroptera: Miridae) contained six major compounds, including (E)-2-hexenal, (E)-2-hexen-1-ol, (E)-2-octenal, (E)-2-octen-1-ol (E)-2-heptenal, and (Z)-3-octen-1-ol. Males and females did not differ significantly in the relative compositions of identified compounds. In feeding trials, six bird species [robin (Turdus migratorious), blue jay (Cyanocitta cristata), brown thrasher (Toxostoma rufum), killdeer (Charadrius vociferus), starling (Sturnus vulgaris), and house wren (Troglodytes aedon)] demonstrated feeding aversions towards L. robiniae, implying that black locust bugs are chemically defended. Bugs discharged the liquid contents of their MTG when attacked, thereby producing a strong and distinct odor. Some birds immediately ejected bugs out of their mouth after biting them, suggesting that the MTG secretion was a deterrent. 相似文献
108.
Laurie Pesant Joseph Matta Cuong Pham-Huu François Garin Pierre Bernhardt Charlotte Pham Marc-Jacques Ledoux 《Topics in Catalysis》2004,(1):281-286
Platinum catalyst supported on a medium surface area -SiC was successfully used for the catalytic combustion of model carbon particles and compared to a catalyst supported on a low surface area -SiC. The -SiC-based catalyst showed no deactivation as a function of cycling tests while a strong deactivation was observed on the -SiC-based catalyst. This deactivation was attributed to the progressive encapsulation of the platinum particles by a layer of silica which built up during the combustion cycle. These results render possible the use of Pt/-SiC catalyst as a diesel carbon particle catalytic filter with continuous regeneration. 相似文献
109.
Wen-I Li Michael Perzl Joachim Heyder Robert Langer Joseph D. Brain K.-H. Englmeier Ralph W. Niven David A. Edwards 《Journal of aerosol science》1996,27(8):1269-1286
The results of numerical simulations of the aerodynamics and of solid aerosol deaggregation phenomena arising in the process of airflow through various model human oropharyngeal cavities are reported. Special attention is given to the relevance of these simulations to the inhalation of dry-powder therapeutic aerosols. Several two- and three-dimensional mouth and throat geometries (terminating just beyond the larynx) are considered. Cross-sectional area-averaged viscous stress values are numerically determined as a function of distance from the mouth opening. These values, ranging from approximately 10 to 500 dyn cm−2, are compared with estimates of Van der Waals attractive forces per unit area of particle-particle contact so as to evaluate the ability of the flowing airstream to deaggregate aerosol particles that enter the mouth in an aggregated state (held together principally by Van der Waals attractive forces). Estimates of airstream viscous stress differ markedly depending on whether the geometry is two- or three-dimensional. Quantitative differences between flow in a 90°-bend model and an oropharyngeal geometry numerically reconstructed from a cast of a human mouth and throat are especially significant in regards to the ability of the airstream to break apart particle agglomerates. For all geometries it is observed that increasingly smaller particle agglomerates may potentially be separated as the airflow rate increases from 30 to 2001 min−1. At the highest airflows, aggregated particles of diameter near to or even below 1 μm may potentially be separated by the airflow. If separation of particle agglomerates is to occur, it appears far more likely to take place in the throat than in the mouth. This is especially apparent for the more physiologically faithful oropharyngeal geometries considered. 相似文献
110.
A shock tube technique was employed to study the fast pyrolysis of cellulose with methane under conditions of high temperature, high heating rate, short reaction time, and rapid quenching. The effects of temperature, methane atmosphere, and reaction time are investigated. Experiments were carried out at temperatures between 700 and 2200°C in 1% methane (diluted in argon), and comparisons in the yields of major gas products are made with the results obtained in pure argon atmosphere. The total gas yield decreased about 25–30% in methane. The principal gas products—carbon monoxide, carbon dioxide, and acetylene, except ethylene—were significantly decreased in methane as compared to the yields in pure argon. An increase of about 25% in ethylene yield in methane over argon was observed. The onset of the decomposition of cellulose and the evolution of major pyrolysis products were changed with the reaction times, which also affected the amplitude and the distribution of the pyrolysis products. © 1994 John Wiley & Sons, Inc. 相似文献