University of Windsor

About: University of Windsor is a education organization based out in Windsor, Ontario, Canada. It is known for research contribution in the topics: Population & Argumentation theory. The organization has 10654 authors who have published 22307 publications receiving 435906 citations. The organization is also known as: UWindsor & Assumption University of Windsor.

Wear regimes and transitions in Al2O3 particulate-reinforced aluminum alloys

Abstract: The effect of the applied load on the unlubricated sliding wear behaviour of a 6061 Al alloy reinforced with 20 vol.% Al2O3 particles was studied. Experiments were performed using a block-on-ring type wear rig. Wear of the control alloy, i.e. the unreinforced 6061 Al, and the wear of the counterface (AISI 52100 steel) were also studied. Three wear rate regimes were observed in the composite: in region I, i.e. at low loads (less than 10 N) the wear rates were less than 2 × 10−5 mm3 m−1. This was followed by a transition region where the rates increased by a factor of 102. In region II that covered mid-range loads the wear rates raised steadily, 10−3 to 10−2 mm3 m−1, up to 230 N where a second transition took place to a severe wear regime (region III). In the unreinforced 6061 Al, only regions II and III were observed. At low loads the wear resistance of the composite (region I) was two orders of magnitude higher than that of the unreinforced alloy. In region II there was no significant difference between the wear rates of the unreinforced and the Al2O3-reinforced alloys. However, the transition from region II to III occurred at a lower load in the unreinforced 6061 Al (60 N). Metallographic studies performed to delineate the rate controlling wear mechanisms revealed that low wear rates in region I resulted from the load-bearing capacity of Al2O3 particles and the formation of transfer layers on the contact surfaces of the composites. When the applied load exceeded the fracture strength of the particles, particles at the surface were fractured and wear occurred by a process of subsurface crack growth. Al2O3 particles promoted crack nucleation and growth and acted as third-body abrasives resulting in wear rates similar to those in the unreinforced 6061 Al. The transition to severe wear rate regime is shown to be controlled by frictional heating to a critical temperature. This temperature was higher for the composite material for which the transition was postponed to higher loads.

The contribution of naming speed to the simple view of reading

Abstract: The purpose of this study was to investigate whether naming speed makes a contribution to the prediction of reading comprehension, after taking into account the product of word decoding and listening comprehension (i.e., the Simple View of Reading; (Gough, P.B. & Tunmer, W.E. (1986). Remedial and Special Education 7 ,6 - 10)), and phonological awareness. In grade 3, word decoding was measured with the Woodcock ((1998). Woodcock Reading Mastery Tests - Revised. Circle Pines, MN: American Guidance Services). Word Identification and Word Attack subtests, listening comprehension with the Woodcock (1991) (Woodcock Language Proficiency Battery - Revised. Chicago: Riverside Publishing Company) test of Listening Comprehension, naming speed with a picture naming task, and 4 measures assessed phonological awareness. Reading comprehension was assessed in grades 3, 4, and 5 with the Woodcock (1998) Passage Comprehension subtest and in grade 5 with the Gates- MacGinitie reading test. The Simple View was evaluated twice: first, with a pseudoword measure for decoding (Grapheme-Phoneme-conversion product) and, second, with a word identification measure for decoding (word recognition product). Hierarchical regression and commonality analyses indicated that the decoding and listening com- prehension products accounted for considerable variance in reading comprehension. Naming speed had a small but significant effect after accounting for the Grapheme- Phoneme-conversion product (2-3%), but little effect after accounting for the word- recognition product (0-2%). Subgroup analyses indicated that naming speed had its primary effect for less able readers. Commonality analyses supported the interpretation that naming speed contributes after the Grapheme-Phoneme-conversion product but not after the word recognition product because naming speed has already had its effect upon word recognition. These results indicate that it is important how the Simple View decoding term is defined, and that the Simple View may be incomplete, especially for less able readers.

Surface-enhanced Raman scattering in the ultraviolet spectral region: UV-SERS on rhodium and ruthenium electrodes

Abstract: We report the first observation of surface-enhanced Raman scattering (SERS) excited with ultraviolet (UV) light from transition metal electrodes. Adsorbed pyridine and SCN- on rough rhodium (Rh) and ruthenium (Ru) electrodes, respectively, have been studied using 325 nm laser excitation. In contrast, the best enhancers in the visible and near infrared, silver and gold, do not produce UV-SERS. The experimental data of UV-SERS are in agreement with our preliminary theoretical calculation based on the electromagnetic enhancement mechanism. The enhancement factor is about 2 orders of magnitude for the Rh and Ru electrodes when they are excited at 325 nm.

Planning product disassembly for material recovery opportunities

Abstract: SUMMARY This paper addresses an increasingly important aspect of product design and its relationship to life-cycle costing: disassembly for material recovery opportunities (MRO). MRO is defined as an opportunity to reclaim post-consumer products for recycling, remanufacturing and re-use. The authors have developed a methodology which can be used to identify and assess cost-effective characteristics of disassembly for the recovery of products. The central focus of this paper is aimed at improving the efficiency of the disassembly planning process and generating an optimal disassembly sequence. Four criteria are established to optimize the generation of the disassembly sequence: (1) material compatibility, (2) clustering for disposal, (3) concurrent disassembly operations, and (4( maximizing yield. In this paper we define the ‘disassemblability’ of a product as the ability to optimize the design and disassembly process for removal of specific pans or materials in a manner which will minimize costs. Steps ha...