Showing papers by "Curtin University published in 1989"
TL;DR: In this paper, a written diagnostic instrument was developed to identify grade-11 and -12 students' misconceptions and misunderstandings of the chemistry topic covalent bonding and structure, which was used to identify student understanding from interviews, student-drawn concept maps, and free-response questions.
Abstract: This article initially outlines a procedure used to develop a written diagnostic instrument to identify grade-11 and -12 students' misconceptions and misunderstandings of the chemistry topic covalent bonding and structure. The content to be taught was carefully defined through a concept map and propositional statements. Following instruction, student understanding of the topic was identified from interviews, student-drawn concept maps, and free-response questions. These data were used to produce 15 two-tier multiple-choice items where the first tier examined content knowledge and the second examined understanding of that knowledge in six conceptual areas, namely, bond polarity, molecular shape, polarity of molecules, lattices, intermolecular forces, and the octet rule. The diagnostic instrument was administered to a total of 243 grade-11 and -12 chemistry students and has a Cronbach alpha reliability of 0.73. Item difficulties ranged from 0.13 to 0.60; discrimination values ranged from 0.32 to 0.65. Each item was analyzed to ascertain student understanding of and identify misconceptions related to the concepts and propositional statements underlying covalent bonding and structure.
227 citations
TL;DR: In this article, the results related to the structure of froths and their water content are reviewed and an explanation for the way in which water, and hence entrained particles, are transported from pulp to froth column to concentrate.
Abstract: Papers on entrainment in conventional froth flotation are reviewed and the results related to the structure of froths and their water content. The strong correlation observed between the recovery of gangue and the recovery of water, in both batch and continuous tests, is discussed and compared with the effect of water recovery on the recovery of hydrophobic (valuable) particles. Data on the structure and water content of flotation froths is summarized and an explanation sought for the way in which water, and hence entrained particles, are transported from pulp to froth column to concentrate.
154 citations
TL;DR: The data converge on the finding that peer-led education appears to be efficacious in reducing alcohol use across a variety of settings and cultures.
Abstract: In 1985 the Division of Mental Health, World Health Organization, Geneva, convened a group of investigators from centers in four countries-Australia, Chile, Norway, Swaziland-to participate in a pilot study on the efficacy of school-based alcohol education. The goal of the educational program was to delay onset and minimize involvement of alcohol use among 13- to 14-year-old adolescents. Twenty-five schools in the four countries, representing middle- and lower-class populations, were randomly assigned to peer-led education, teacher-led education, or a control condition. The educational program was derived from social-psychological theory and etiological research on adolescent alcohol use. The program focused on the social and environmental influences to drink alcohol and skills to resist those influences. It consisted of five lessons over 2 months. Baseline and posttest data measured alcohol use knowledge, attitudes, skills, and friends' drinking patterns. Data were collected immediately prior to and 2 mo...
94 citations
TL;DR: Consistent differences in bill length between the sexes suggest that males and females may exploit different floral resources or different proportions of the same resources.
Abstract: The bills and tongues of nectar-feeding birds differ from continent to continent. The major differences are that: (i) the tongues of A Australian honeyeaters are broader any more fimbricated at the tip than the bifurcated tongues of sunbirds and hummingbirds; (ii) the bills of hummingbirds are more uniformly narrow and taper less markedly towards their tips than those of sun-birds and honeyeaters; and (iii) bill curvatures are generally greater for sunbirds and honey-creepers than for hummingbirds. A variety of hummingbirds has straight or even slightly upturned bills, while bills for all sunbirds, honeycreepers and honeyeaters are decurved to some extent. Despite differences in tongue morphology, hummingbirds, sunbirds and honeyeaters extract nectar at a similar range of rates, averaging approximately 40 γL s−1 from ad libitum feeders, and 1–15 γL−1 from flowers. All tongues collect nectar by capillarity, with licking rates of 6–17 s−1. Licking behaviour has been little studied, although speeds of licking respond to changes in sugar concentration and corolla length. The tongues of honeyeaters are broad, and may need to be brush-tipped in order to allow capillary collection of nectar. Brush-tipped tongues can cover large surface areas on each lick, and may allow honeyeaters to exploit nectar and honeydew that is thinly spread over large surface areas. Bill lengths of nectarivorous birds are similar in all regions, though species of hummingbird have the shortest and longest bills. Bill lengths largely determine the range of floral lengths that can be legitimately probed. Maximum floral lengths exceed bill lengths, since hummingbirds, sunbirds and honeyeaters protrude their tongues beyond the tips of their bills. Rates of nectar extraction, however, decline rapidly once the floral length exceeds bill length. Decurved bills may have evolved in honeyeaters and sunbirds to enable perching birds to reach flowers at the ends of branches more easily. Consistent differences in bill length between the sexes suggest that males and females may exploit different floral resources or different proportions of the same resources. For honeyeaters and sunbirds, males have longer bills than females, but the reverse is true for many hummingbirds.
92 citations
TL;DR: The whole-rock Pb-Pb method has been used to date four of the younger, mainly adamellite, late-tectonic plutonic phases within the 3.5 Ga Shaw Batholith of the Archaean east Pilbara Block as mentioned in this paper.
Abstract: The whole-rock Pb-Pb method has been used to date four of the younger, mainly adamellite, late-tectonic plutonic phases within the ca. 3.5 Ga Shaw Batholith of the Archaean east Pilbara Block. Three suites give ages within error of 2966 Ma (Porphyritic Granites at 2948±50 Ma, Leuco-adamellites at 2943±46 Ma and Garden Creek Adamellite at 3007±48 Ma). The post-tectonic Cooglegong Adamellite gives an age of 2847±34 Ma. The Sm-Nd model isotopic systematics of all four suites indicate derivation from crust ranging between ca. 3200 and 3600 Ma in age. The sources for these four younger plutonic phases were heterogeneous and, although exhibiting some isotopic characteristics of the older (3.5−3.3 Ga) calc-alkali plutonic suites, were more depleted in the LIL elements Rb, U and Th. In addition, the Garden Creek Adamellite and the Cooglegong Adamellite lack the very fractionated and HREE-depleted REE patterns characteristic of both the older calc-alkali plutonic rocks and the Porphyritic Granites and Leuco-adamellites. The crust underlying the Shaw Batholith at ca. 2950 Ma must have been both markedly heterogeneous and variably depleted, a conclusion consistent with the complex tectonic and plutonic evolution of this region.
92 citations
TL;DR: In this paper, the authors used stepwise Pb-evaporation directly in the ion source of a thermal ionization mass spectrometer to verify > 4 Ga zircon ages in the metaconglomerate from the Archean Jack Hills metasedimentary belt.
78 citations
77 citations
TL;DR: The parents of 30 children referred to speech pathology because of vocal nodules completed the Walker Problem Behavior Identification Checklist (WPBIC) on their children, and the nodule children had significantly higher scores on the scales for acting out, distractibility, disturbed peer relations, and immature behaviors.
Abstract: The parents of 30 children referred to speech pathology because of vocal nodules completed the Walker Problem Behavior Identification Checklist (WPBIC) on their children. These checklist responses ...
65 citations
TL;DR: Kimberlites from central west Greenland during the Early Palaeozoic have initial 87Sr86Sr between 0.7028 and 0.9 as discussed by the authors, whereas lamproite sources evolved in isolation from the convecting mantle for > 1000 Ma, probably within the subcontinental lithospheric mantle of the Greenland craton.
60 citations
TL;DR: In this article, a planar cross section of one of the natural fission reactor zones at the Oklo U mine was analyzed to determine the abundances and isotopic composition of U, Mo, Ru, Pd, Ag, Cd, Sn, Te and Nd.
57 citations
TL;DR: In this paper, the costs and benefits of multi-skilling at enterprise level are analyzed using current Australian experience as a reference point, and some suggestions for future research and practice in the area are raised.
Abstract: Using current Australian experience as a reference point, the costs and benefits of multi‐skilling are critically analysed. First, an attempt is made to identify key organisational elements involved in programmes of multi‐skilling at enterprise level. Secondly, some of the proposed benefits and possible costs associated with such developments are identified and discussed. Finally, some suggestions for future research and practice in the area are raised.
TL;DR: It is shown that the energy feature detector is a true projection and does not proliferate edges when applied to a line-drawing, whereas several of the conventional operators do.
TL;DR: It is suggested that, in survivors, bony and soft‐tissue injuries to zygapophyseal joints may result in considerable pain and dysfunction and may predispose to early arthritis.
Abstract: Three zygapophyseal joints from each of 31 lumbar spines of subjects who died of injuries (mostly as a result of motor-vehicle accidents) were sectioned for low-power histological study. Bony injuries, in the form of fractures of the superior articular process or infractions of the subchondral bone plate, were found in 11 of the 31 subjects and soft-tissue injuries to the capsule or articular cartilage were found in one-or-more joints in 24 of the 31 subjects, with capsular and articular-cartilage damage in 77% of cases. Healed injuries of a similar type, which were unrelated to the cause of death, were found in other lumbar spines. None of these lesions was diagnosed by standard radiological examination of the spine post mortem. It is suggested that, in survivors, bony and soft-tissue injuries to zygapophyseal joints may result in considerable pain and dysfunction and may predispose to early arthritis.
TL;DR: A longitudinal case study was made of a sub-unit of a nursing home to examine the perceptions and social interactions of patients and staff after introduction of a resident dog.
Abstract: A longitudinal case study was made of a sub-unit of a nursing home to examine the perceptions and social interactions of patients and staff after introduction of a resident dog. A behavioral mapping procedure was used to determine staff and patient interactions 6 weeks before and 6 weeks and 22 weeks after the dog's arrival. Interviews were also conducted with patients and staff. Six weeks after the dog's arrival, a significant increase in frequency of interactive behaviors was seen for both staff and patients. By 22 weeks, behaviors for patients had reverted to base-line levels, while remaining high for staff.
TL;DR: In this article, the relative abundances of the 24-ethylcholestane diastereomers were measured in nine pairs of closely adjacent samples of coals and shales which represent a range of geological ages and different sedimentary basins.
TL;DR: In this article, the oxidation of pyrite of particle size less than 45 μm has been studied by simultaneous thermogravimetry- differential thermal analysis (TG- DTA) at a heating rate of 2.5 ° C min−1 in an air atmosphere.
TL;DR: The Moos's Work Environment Scale (WES) as mentioned in this paper is a scale designed for assessing the school learning environment, and it has considerable potential for use with teachers despite the fact that it was designed initially for any work milieu.
Abstract: Past work on psychosocial environments can be divided usefully into research involving students' perceptions of their classroom-level environment and studies of teachers' perceptions of their school-level environment. Of several instruments for assessing the school learning environment, Moos's Work Environment Scale (WES) is unique in its focus on the school as a work setting and it has considerable potential for use with teachers despite the fact that it was designed initially for any work milieu. Its 10 dimensions of Involvement, Peer Cohesion, Staff Support, Autonomy, Task Orientation, Work Pressure, Clarity, Control, Innovation and Physical Comfort seem quite well-suited to describing salient features of the school teacher's work environment. Administration of a slightly reworded version of the WES to a large sample of teachers responding to both an actual form (N=599) and a preferred form (N=543) attested to the internal consistence reliability and discriminant validity of both forms with ei...
TL;DR: A synthesis of hundreds of meta-analyses of many thousands of individual past research studies was used to identify instructional variables (especially curriculum and classroom environment variables) and school variables which are linked consistently with student achievement as mentioned in this paper.
TL;DR: This review attempts to consolidate and interpret available data and highlight areas where further investigations appear warranted into the influence of attributes such as mass, wing length and leg morphology upon the speed, acceleration, mode and energetic cost of movement by birds between flowers when foraging for nectar.
Abstract: Nectar-feeding birds are prominent in many parts of the world, and vary with respect to body size. Despite the availability of considerable morphometric data, few concerted efforts have been made to assess the influence of attributes such as mass, wing length and leg morphology upon the speed, acceleration, mode and energetic cost of movement by birds between flowers when foraging for nectar. This review attempts to consolidate and interpret available data and highlight areas where further investigations appear warranted. Australian honeyeaters are generally larger, and American hummingbirds smaller, than Hawaiian honeycreepers and sunbirds of Africa or Asia. Sunbirds, honeyeaters and honeycreepers generally perch while extracting nectar from flowers. Hummingbirds usually hover, apparently because suitable perches close to flowers are lacking, and not because hovering increases the speed at which flowers can be visited. Honeyeaters move from one flower to another at speeds that are at least as great as those for hummingbirds. Most passerine nectarivores need to ingest more nectar per day than hummingbirds in order to maintain energy balance, some species devoting more than 60% of the day to foraging. The major consequence of reduced foraging activity by hummingbirds, which spend only 5–30% of the day in this manner, appears to be male emancipation from nest construction and care of offspring. Large nectarivores have a greater capacity to store surplus food and to fast than smaller birds, and so can take advantage of short-lived peaks in nectar abundance. Nectarivores such as honeyeaters should therefore be favoured by the rapid diurnal changes in nectar availability which are characteristic of many Australian and African habitats. Body mass also determines the likely access to rich sources of nectar through size-related interspecific dominance hierarchies. In all families, larger species tend to monopolize the most rewarding nectar supplies, forcing smaller subordinate species to use poorer, more scattered sources. Within particular species, males usually have longer wings and greater masses than females. These variations imply that the two sexes differ with regard to their foraging ecology, although few supporting data are currently available.
TL;DR: It is argued that not all topics proposed by Bhaskar are absolutely necessary, and that his list contains disturbing omissions and unrealistic expectations of accounting students' time.
Abstract: Bhaskar (1982, 1983) proposed a list of 26 topics, classified under three categories (computer science, computer as a computational tool, computer-aided instruction), for the use of computers in accountancy courses. This scheme is argued to be confusing, as some topics are classified wrongly, and is replaced by a new seven-category scheme. Among other things, computer-aided instruction is found to have doubtful value as judged from the collected experimental evidences. An important question is raised as to the necessity and desirability of the use of computers in accountancy courses. It is argued that not all topics proposed by Bhaskar are absolutely necessary, and that his list contains disturbing omissions and unrealistic expectations of accounting students' time. A new list of necessary computing topics is proposed. Each topic requires 2–3 hours of terminal time during a supervised laboratory session, and can be incorporated easily into existing accounting curricula. It is felt that a postgrad...
TL;DR: In this article, the authors present the findings of an interpretive investigation of the implemented and perceived curriculum in two grade 10 science classes at a school in which the main goal was to learn in a hands-on and minds-on manner.
Abstract: This purpose of this paper is to present the findings of an interpretive investigation of the implemented and perceived curriculum in two grade 10 science classes at a school in which the main goal was to learn in a hands-on and minds-on manner. The study commenced with general questions concerning opportunities that students had to engage in activities in these two classes. As the study progressed, a number of specific foci emerged and were pursued in depth
TL;DR: In this paper, the mass spectrometric isotope dilution technique was used to measure the elemental abundances of these elements in a number of sandstones and shales in the immediate vicinity of Reactor Zone 9 at the Oklo mine site.
TL;DR: In this paper, the identification of nine tetramethylnaphtalene (TeMN) isomers in crude oils using capillary GC-mass spectrometry (MS).
TL;DR: In this article, the surface reaction for fresh Calgon GRC22 carbon is concluded that the diffusion of AuCl4− to the external carbon surface dictates the deposition rate, which is numerically similar to the rate of gold adsorption from Au(I) cyanide solution, where the gold is adsorbed on the carbon as Au(CN)2− ions.
TL;DR: A double-step analysis of a discrete aiming movement found that subjects could respond more appropriately and effectively to a deliberate rather than a random error, and an undershoot error rather than an overshoot error.
TL;DR: Black opaque hydrocarbon rims about 0.05 mm thick are preserved around detrital monazite grains in Permian-Triassic arenites of the norther Perth Basin, Western Australia.
Abstract: Black opaque hydrocarbon rims about 0.05 mm thick are preserved around detrital monazite grains in Permian-Triassic arenites of the norther Perth Basin, Western Australia. Chromatographic analysis indicates derivation from oil chemically like that elsewhere in the sequence, and the rims seem to be remnants of oil, which was largely flushed away. The hydrocarbon rims may have adhered to the monazite grains because of irradiation; they are not found on other grains. Monazite-rich heavy mineral bands are probably responsible for abnormally high radioactivity recorded locally by gamma-ray logs in wells penetrating the sandstones. A preliminary search has revealed similar rims around monazite in other Western Australian arenites ranging in age from Silurian to Cretaceous. Thin-section examination of heavy mineral concentrations may therefore be a useful, simple technique to indicate the former presence of hydrocarbons in dry arenites.
TL;DR: In this paper, a comparison of the oxidation of pyrite of particle size < 45 and 90-125 μm has been made, and the effects of changing the particle size, heating rate and atmosphere are discussed.
TL;DR: In this paper, a case study of a successful change attempt in a sixth-grade mathematics class was presented, where assessments of actual and preferred environment were used in an attempt to improve the climate of the class, a significant improvement occurred only on the dimension on which change had been attempted.
Abstract: Despite international interest in research on classroom environment, very little attention has been given to exploring how mathematics teachers might apply ideas from that research in guiding practical improvements in mathematics classrooms. To facilitate the use of classroom climate assessments, an economical, hand-scorable short form (25 items) of the My Class Inventory was developed. Data supported each scale's internal consistency, discriminant validity, and ability to differentiate between the perceptions of students in different classrooms. Some methods for improving classrooms are illustrated in a case study of a successful change attempt in a sixth-grade mathematics class. When assessments of actual and preferred environment were used in an attempt to improve the climate of the class, a significant improvement occurred only on the dimension on which change had been attempted.
06 Aug 1989
TL;DR: In this paper, the economics associated with the major system components for remote-area power supplies are discussed, and a detailed description of the various system configurations is given, covering diesel generators, battery storage, inverters, photovoltaic and wind-powered generators.
Abstract: The economics associated with the major system components for remote-area power supplies is discussed, and a detailed description of the various system configurations is given. The discussion covers diesel generators, battery storage, inverters, photovoltaic and wind-powered generators. Series, switched and parallel hybrid systems are considered. Results and conclusions based on tests carried out at Murdoch University Energy Research Institute are included. >