Showing papers by "David W. Johnson published in 1979"
TL;DR: In this paper, a teacher is presenting a lesson on the United States Congress and the students are discussing in small groups the reasons why citizens want to be representatives in Congress, one student says the major reason is wanting to help your neighbors and your country, and quotes Roger Mudd (CBS News, December 24, 1976) that a representative in Congress receives more than $400,000 per year in salary and benefits.
Abstract: In a social studies class a teacher is presenting a lesson on the United States Congress. The students are discussing in small groups the reasons why citizens want to be representatives in Congress. One student says the major reason is wanting to help your neighbors and your country. Another student says being a member of Congress is just a way to get rich, and quotes Roger Mudd (CBS News, December 24, 1976) that a representative in Congress receives more than $400,000 per year in salary and benefits. Voices rise as the argument continues. What does the teacher do? Would the teacher encourage the argument, helping students find evidence to support and argue their positions? Or would the teacher try to calm things down and change the topic of discussion? Within any learning situation such conflicts among ideas or opinions are inevitable. They will occur no matter what the teacher does. Learning situations are filled with conflicts among students, between the teacher and the student, and between what a student presently understands and new information being learned. And the current evidence indicates that in most classrooms conflicts are avoided and suppressed (DeCecco & Richards, 1974) and that teachers and students lack the skills and procedures needed for effective conflict management (Deutsch, 1973; Blake & Mouton, 1970; Johnson, 1970) By avoiding and suppressing certain types of conflicts teachers lose valuable opportunities to increase student motivation, creative insight, cognitive development, and learning. Conflicts have the potential for producing both
441 citations
TL;DR: In this paper, six studies involving over 6000 students from kindergarten through college were sequenced over a period of years to develop three relatively independent self-report scales with substantial internal reliability to measure attitudes toward cooperative, competitive, and individualistic interdependence between oneself and others in educational settings.
Abstract: Summary Six studies involving over 6000 students from kindergarten through college were sequenced over a period of years to develop three relatively independent self-report scales with substantial internal reliability to measure attitudes toward cooperative, competitive, and individualistic interdependence between oneself and others in educational settings. The purpose of the scale development was to provide a research tool for social scientists interested in social interdependence. In addition, evidence consistent with a multidimensional view of social interdependence was gathered, and some additional evidence indicating a change in conceptions of the three types of social interdependence in junior high school was found.
108 citations
105 citations
TL;DR: In this paper, experimental results from high-power neutral-beam-injection experiments on the Princeton Large Torus tokamak are reported, showing that ion temperatures of 6.5 keV are achieved at the highest beam powers and lowest plasma densities.
Abstract: Experimental results from high-power neutral-beam--injection experiments on the Princeton Large Torus tokamak are reported. At the highest beam powers (2.4 MW) and lowest plasma densities (n/sub e/(0) = 5 x 10/sup 13/cm/sup -3/), ion temperatures of 6.5 keV are achieved. The ion collisionality v/sub i/* drops below 0.1 over much of the radial profile. Electron heating of ..delta..T/sub e//T/sub e/ approx. = 50% has also been observed, consistent with the gross energy-confinement time of the Ohmically heated plasma, but indicative of enhanced electron-energy confinement in the core of the plasma.
98 citations
TL;DR: In this article, the adsorption of nitric oxide on Cu(100) and Cu(111) surfaces has been studied by combining X-ray and u.v. spectroscopy with low energy electron diffraction.
Abstract: The adsorption of nitric oxide on Cu(100) and Cu(111) surfaces has been studied by combining X-ray and u.v. photoelectron spectroscopy with low energy electron diffraction. At 80 K two molecular states, characterised by N(1s) values of 399.5 and 401 eV, have been assigned to “bent” and “linear” configurations, respectively. The bent form dissociates slowly at 80 K while the linear species desorbs above ≈ 170 K. Assignments of the “bent” and “linear” forms were facilitated by recourse to the known sterochemistry of metal nitrosyl complexes where a correlation between formal charge on the ligand and sterochemistry has been established. Furthermore the results are compared with the adsorption of NO on both clean nickel and nickel whose surface reactivity has been controlled by pre-exposure to oxygen.The N-adatoms arising from dissociation at 80 K are mobile and highly reactive forming N2O which remains on the surface at this temperature. There is no evidence for dinitrogen desorption. The N2O was characterised by both its X-ray and u.v. photoelectron spectra. Cu(100) and Cu(111) behave similarly, Cu(111) being less active than Cu(100) in dissociation. At 80 K with Cu(100) there is evidence from LEED for the formation of an ordered (√2 ×√2)R45° structure superimposed on an increase in the background intensity of the scattered electrons. On warming the adlayer to 290 K well ordered (√2 ×√2)R45°–O structures are present. No ordered structures were observed with Cu(111) at either 80 or 290 K and this is compatible with previous studies of chemisorbed oxygen on Cu(111). At 290 K NO chemisorbed dissociatively on Cu(100) and Cu(111) both fragments being retained at the surface. With Cu(100) the symmetry of the adlayer conformed to a (√2 ×√2)R45° structure.From a curve fitting analysis of the O(1s) data for the adlayer formed on Cu(100) concentrations of the individual surface species O(a), NO(a) and N2O(a) present at 80 K and on thermal activation to 110, 133 and 290 K were calculated.
65 citations
TL;DR: The results indicate that cooperation generally produced more positive attitudes than did either individualization or competition and resulted in higher achievement than did competition and individualization on both the problem-solving and retention tasks.
Abstract: The effects of interpersonal cooperation, competition, and individualization were compared on drill-review, problem-solving, specific-knowledge acquisition, and specific-knowledge retention instructional tasks. Sixty-six fifth graders were included in the study. Males and females were assigned randomly to conditions so that within each condition there were 22 Ss and an equal number of males and females. The results indicate that cooperation generally produced more positive attitudes than did either individualization or competition. Cooperation resulted in higher achievement than did competition and individualization on both the problem-solving and retention tasks, higher achievement than competition and just as high achievement as individualization on the drill-review task, and higher achievement than individualization and just as high achievement as competition on the specific-knowledge-acquisition task.
62 citations
TL;DR: The effects of interpersonal cooperation, competition, and individualistic efforts were compared on math and reading drill-review, story problems, sequencing, triangle identification, and visual sorting according to attributes tasks as discussed by the authors.
56 citations
53 citations
TL;DR: In this paper, it was shown that by suitably controlling the gas influx, it is possible to contract the current channel, decrease impurity radiation from the core of the discharge, and increase the gross energy confinement time, whether the aperture limiters are of tungsten, stainless steel or carbon.
Abstract: Experiments conducted on the PLT tokamak have shown that both plasma-limiter interaction and the gross energy confinement time are functions of the gas influx during the discharge. By suitably controlling the gas influx, it is possible to contract the current channel, decrease impurity radiation from the core of the discharge, and increase the gross energy confinement time, whether the aperture limiters are of tungsten, stainless steel or carbon.
47 citations
TL;DR: Learning-disabled Ss in the cooperative condition learned more swimming skills than did their counterparts in the individual condition, and more friendly interactions in the postinstructional, free-swim periods occurred in the cooperatively structured pairs.
Abstract: Summary The effects of cooperative and individual learning experiences on friendly and hostile interaction between normal-progress and learning-disabled children in free-choice, postinstructional situations were studied. Twelve second and third grade elementary school boys participated in a study utilizing swimming classes. Three normal-progress and three learning-disabled Ss were assigned to each condition. Ss participated in a nine-day swimming course, learning swimming skills either individually or in cooperatively structured pairs. The results indicate that more friendly interactions in the postinstructional, free-swim periods occurred in the cooperative compared to the individual condition. More hostile interactions occurred in the individual condition. Learning-disabled Ss were ignored by their normal-progress peers more in the individual condition. Learning-disabled Ss in the cooperative condition learned more swimming skills than did their counterparts in the individual condition.
43 citations
TL;DR: In this article, the effects of cooperative, individualistic and laissez faire goal structures were compared on interpersonal interaction and attraction between non-handicapped junior high school students and high trainable mentally retarded peers participating in six weekly sessions of a bowling class.
Abstract: The effects of cooperative, individualistic, and laissez faire goal structures were compared on interpersonal interaction and attraction between nonhandicapped junior high school students and high trainable mentally retarded peers participating in six weekly sessions of a bowling class. The results indicate that considerably more positive interactions took place between the nonhandicapped and the handicapped students in the cooperative condition than in the individualistic or laissez faire conditions.
TL;DR: In this paper, the effects of interpersonal cooperation, competition, and individualistic efforts on students' achievement and perceptions of teacher and peer academic and personal support were compared on student's achievement.
Abstract: Summary The effects of interpersonal cooperation, competition, and individualistic efforts were compared on students' achievement and perceptions of teacher and peer academic and personal support. Sixty-nine fourth, fifth, and sixth grade students were included in the study. Males and females were randomly assigned to conditions so that within each condition there were 23 Ss and an approximately equal number of males and females. The results indicate that cooperation promoted stronger perceptions of teacher academic and personal support than did individualistic learning experiences, stronger perceptions of peer academic and personal support than did either competitive or individualistic learning experiences, and higher achievement than did the other two conditions. Competition resulted in higher achievement and stronger perceptions of teacher academic support than did individualistic learning experiences.
TL;DR: A sensitive and specific analytical method was developed to determine the enantiomeric purity of naproxen and gave a mixture of diastereomeric esters displaying baseline separation on liquid chromatography.
TL;DR: In this paper, the volt-second consumption in the PLT tokamak was measured and the measurements reported in this paper provide an empirical basis for establishing the voltsecond requirements for future tokak devices.
Abstract: The volt-second consumption in the PLT tokamak was measured. During the start-up phase, the volt-second consumption is determined primarily by the external and internal flux required to establish the current profile. The resistive volt-second loss on axis is typically < l/4 of the total volt-seconds consumed during the first 180 ms of the discharge. The measurements reported here provide an empirical basis for establishing the volt-second requirements for future tokamak devices.
TL;DR: In this paper, the authors report evidence that selected content is better learned when students write and run compared to when they do not use a computer in a laboratory-like setting, which is supported by the Conference Board of the Mathematical Sciences recommendation that there is a need for "the development of short modules (or units) using computers in problem-oriented situations that emphasize the application of mathematics to the range of problems relevant to today's society".
Abstract: I n recent years there have been several research and development projects dealing with the implementation and verification of the contributions of computing in school and college mathematics. One of the major areas of interest is how computer programming by students in a laboratory-like context contributes to the learning of selected concepts and problem solving. Hatfield (Note 1) reported on an extensive review of the literature in this area and indicated that though the evidence from empirical research is minimal at best, there is considerable support for this approach (a computing laboratory) as an aid in the study of many mathematical concepts and for mathematical problem solving. This view is also supported by the Conference Board of the Mathematical Sciences (CBMS) recommendation that there is a need for "the development of short modules (or units) using computers in problem-oriented situations that emphasize the application of mathematics to the range of problems relevant to today's society" (CBMS, 1972, p. 9). Research reports by Hatfield and Kieren (1972), Milner (1973), Ronan (1971), Wilkinson (1973), and Holoien (1971), to name a few, all report evidence that selected content is better learned when students write and run
TL;DR: In this article, the rate constants for hydroxymethyl radicals with a number of solutes are studied and the spectra of the products characterised, including the formation of adducts between CH2OH and the solute, but in some cases these decompose by an intramolecular electron transfer to yield formaldehyde and a protonated or unprotonated radical anion.
Abstract: The reactions of hydroxymethyl radicals, ·CH2OH, with a number of solutes are studied and the spectra of the products characterised. Evidence is presented for the formation of adducts between ·CH2OH and the solute, but in some cases these decompose by an intramolecular electron-transfer to yield formaldehyde and a protonated or unprotonated radical-anion. In the case of nitrobenzene addition is to the —NO2 group and decomposition of the adduct is shown to be acid catalysed. Galvinoxyl reacts with ·CH2OH to form galvinoxyl anion, but the low yield of this product indicates the occurrence of a second reaction with formation of a non-absorbing product. An adduct may also be formed in the reaction with p-dinitrobenzene. The rate constant for the reaction of ·CH2OH with benzyl radicals is evaluated from the dependence of the decay of the latter on the concentration of benzyl chlorde. The rate constants (dm3 mol–1 s–1) for these reactions of ·CH2OH are: nitrobenzene, (3.9 ± 0.3)× 106; p-dinitrobenzene, (1.51 ± 0.25)× 108; galvinoxyl, 2.6 × 108(for formation of galvinoxyl anion), 1.8 × 109(for other product); benzyl radicals, (6.7 ± 0.6)× 109.The reactions of ·CH2OH from this paper and the literature are divided into those reactions with radicals which have rate constants within an order of magnitude of the diffusion-controlled rate and with non-radical species. The rate constants, k, for addition to nitro-compounds depend on the electron affinity, EA(eV), according to log10k= 8.8 EA+ constant.
01 Jan 1979
TL;DR: In this article, the authors categorized PLT discharges in terms of energy balance into three types: radiation dominated (RD), transport dominated (TD), and an intermediate type (TR) control of plasma edge conditions is essential for the formation of these types.
Abstract: PLT discharges are categorized in terms of energy balance into three types: radiation dominated (RD); transport dominated (TD), and an intermediate type (TR) Control of plasma edge conditions is essential for the formation of these types Measurements and calculations show the relative importance of radiation, transport, and electron-ion coupling in different regions of the discharge Ion heating for neutral beam injection is found to be effective in all types Electron heating by neutral beam injection is only consistently obtained for TD discharges
TL;DR: The urinary production rate of pregnenolone has been determined for a male subject using 7,7-d2-pregnenolones as an isotopic tracer using 7-7- d2- pregnenolsone as a tracer.
Abstract: The urinary production rate of pregnenolone has been determined for a male subject using 7,7-d2-pregnenolone as an isotopic tracer.
TL;DR: Germination was best in the presence of outer bark, sapwood, and leaf tissue of sugar maple and red maple and was poorest in the absence of fresh inner bark tissue excised from red maple; Germ-tube development also varied with type of tissue and treatment of tissue.
Abstract: Ascospore germination of Eutypella parasitica Dav. and Lor. occurred over a temperature range of 12 to 38 °C. Over 90% of the spores which failed to germinate at lower temperatures germinated within 24 h when placed at 24 °C. Percent germination of ascospores varied in the presence of sugar maple and red maple tissue extracts. Germination was best in the presence of outer bark, sapwood, and leaf tissue of sugar maple and red maple and was poorest in the presence of fresh inner bark tissue excised from red maple. Germ-tube development also varied with type of tissue and treatment of tissue. Long, slender, branching germ tubes developed from spores in the presence of nonsterile leaf, bark, and sapwood, whereas short, thick germ tubes developed in the presence of sterilized leaf tissue and sterilized red maple bark. Age of wounded tissue also influenced percent germination of ascospores. Generally germination was higher when pH of these tissues was greater than 5.6. Mycelial growth was best at 29 °C. Growth ...
TL;DR: Anisyl substituted stilbenes undergo concommitant thermal rearrangement and loss of a halogen atom with dealkylation in pyridine hydrochloride.