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Sample records for magnetic behavioral improvisation

  1. Structural and Magnetic Behavioral Improvisation of Nanocalcium Hexaferrites

    Energy Technology Data Exchange (ETDEWEB)

    Sable, Sharad N., E-mail: sharadtz@hotmail.co [Department of Applied Physics, Priyadarshini College of Engineering, Nagpur (India); Rewatkar, Kishor G. [Department of Physics, Dr. Ambedkar College, Dikshabhumi, Nagpur (India); Nanoti, Vivek M. [Priyadarshini College of Engineering, Nagpur (India)

    2010-04-15

    In modern technoscientific era, the industrial application of nanomaterials has grabbed a paramount importance owing to their improved characteristics. Hexagonal ferrites especially M-type ferrites have been proved to be the promising candidates for nanomaterials by virtue of their ease of applicability in high density recording media, microwave absorption devices, magneto-optic recording media, etc. Keeping a bird's view over, the samples of varied combinations of M-type substituted hexaferrites are synthesized using sol-gel combustion route by blending nitrates and chlorides as oxidants accompanied with fuels like urea, glycine, citric acid, etc. as reducing agents. The substitution of Co{sup 2+} and Sn{sup 4+} ions lie essentially in the octahedral and tetrahedral sites. As the Fe{sup 3+} ions are being replaced by Co{sup 2+} and Sn{sup 4+} ions, the probability of having oxygen vacancies in the structure was found to be greatly reduced. The magnetic particles produced by conventional solid state reactions are often larger than those produced by sol-gel combustion route. Larger particles of magnetic oxides generally exhibit multidomain magnetic structure whereas nanosized particles generally exhibit single domain magnetic structure. The simultaneous or coupled divalent and tetravalent substitution of Co{sup 2+} and Sn{sup 4+} for Fe{sup 3+} ions greatly helps to improvise the magnetic parameters such as Curie temperature, coercivity, remanent magnetization, saturation magnetization, etc. The structural comparison is being analyzed through the XRD, TEM. The samples so synthesized are found to be reseasonably homogeneous and the average particle size of the sample synthesized is found to be in the nanorange. The structural and magnetic properties are observed be improved upon those of the samples reported earlier. This confirms the more viability of such samples in the various applications of digital data devices. Further attempts could possibly lead to

  2. Musical Improvisation Behavior of Young Children.

    Science.gov (United States)

    Flohr, John W.

    Musical improvisation behavior of 4-, 6-, and 8-year-old children who played Orff xylophones during ten 15-minute sessions is described in this paper. Each session involved three improvisatory phases. Phase I consisted of free exploration; Phase II consisted of short verbally stimulated musical tasks (two imitation and six improvisational tasks);…

  3. The Effects of Improvisational Music Therapy on Joint Attention Behaviors in Autistic Children: A Randomized Controlled Study

    Science.gov (United States)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2008-01-01

    The purpose of this study was to investigate the effects of improvisational music therapy on joint attention behaviors in pre-school children with autism. It was a randomized controlled study employing a single subject comparison design in two different conditions, improvisational music therapy and play sessions with toys, and using standardized…

  4. The Effects of Improvisational Music Therapy on Joint Attention Behaviors in Autistic Children: A Randomized Controlled Study

    Science.gov (United States)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2008-01-01

    The purpose of this study was to investigate the effects of improvisational music therapy on joint attention behaviors in pre-school children with autism. It was a randomized controlled study employing a single subject comparison design in two different conditions, improvisational music therapy and play sessions with toys, and using standardized…

  5. The neuroscience of musical improvisation.

    Science.gov (United States)

    Beaty, Roger E

    2015-04-01

    Researchers have recently begun to examine the neural basis of musical improvisation, one of the most complex forms of creative behavior. The emerging field of improvisation neuroscience has implications not only for the study of artistic expertise, but also for understanding the neural underpinnings of domain-general processes such as motor control and language production. This review synthesizes functional magnetic resonance imagining (fMRI) studies of musical improvisation, including vocal and instrumental improvisation, with samples of jazz pianists, classical musicians, freestyle rap artists, and non-musicians. A network of prefrontal brain regions commonly linked to improvisatory behavior is highlighted, including the pre-supplementary motor area, medial prefrontal cortex, inferior frontal gyrus, dorsolateral prefrontal cortex, and dorsal premotor cortex. Activation of premotor and lateral prefrontal regions suggests that a seemingly unconstrained behavior may actually benefit from motor planning and cognitive control. Yet activation of cortical midline regions points to a role of spontaneous cognition characteristic of the default network. Together, such results may reflect cooperation between large-scale brain networks associated with cognitive control and spontaneous thought. The improvisation literature is integrated with Pressing's theoretical model, and discussed within the broader context of research on the brain basis of creative cognition.

  6. The effects of improvisational music therapy on joint attention behaviors in autistic children: A randomized controlled study

    DEFF Research Database (Denmark)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2008-01-01

    The purpose of this study was to investigate the effects of improvisational music therapy on joint attention behaviors in pre-school children with autism. It was a randomized controlled study employing a single subject comparison design in two different conditions, improvisational music therapy a...... skills in children than play. Session analysis showed significantly more and lengthier events of eye contact and turn-taking in improvisational music therapy than play sessions. The implications of these findings are discussed further.......The purpose of this study was to investigate the effects of improvisational music therapy on joint attention behaviors in pre-school children with autism. It was a randomized controlled study employing a single subject comparison design in two different conditions, improvisational music therapy...... and play sessions with toys, and using standardized tools and DVD analysis of sessions to evaluate behavioral changes in children with autism. The overall results indicated that improvisational music therapy was more effective at facilitating joint attention behaviors and non-verbal social communication...

  7. The effects of improvisational music therapy on joint attention behaviors in autistic children: A randomized controlled study

    DEFF Research Database (Denmark)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2008-01-01

    and play sessions with toys, and using standardized tools and DVD analysis of sessions to evaluate behavioral changes in children with autism. The overall results indicated that improvisational music therapy was more effective at facilitating joint attention behaviors and non-verbal social communication...

  8. Cortical regions involved in the generation of musical structures during improvisation in pianists.

    Science.gov (United States)

    Bengtsson, Sara L; Csíkszentmihályi, Mihály; Ullén, Fredrik

    2007-05-01

    Studies on simple pseudorandom motor and cognitive tasks have shown that the dorsolateral prefrontal cortex and rostral premotor areas are involved in free response selection. We used functional magnetic resonance imaging to investigate whether these brain regions are also involved in free generation of responses in a more complex creative behavior: musical improvisation. Eleven professional pianists participated in the study. In one condition, Improvise, the pianist improvised on the basis of a visually displayed melody. In the control condition, Reproduce, the participant reproduced his previous improvisation from memory. Participants were able to reproduce their improvisations with a high level of accuracy, and the contrast Improvise versus Reproduce was thus essentially matched in terms of motor output and sensory feedback. However, the Improvise condition required storage in memory of the improvisation. We therefore also included a condition FreeImp, where the pianist improvised but was instructed not to memorize his performance. To locate brain regions involved in musical creation, we investigated the activations in the Improvise-Reproduce contrast that were also present in FreeImp contrasted with a baseline rest condition. Activated brain regions included the right dorsolateral prefrontal cortex, the presupplementary motor area, the rostral portion of the dorsal premotor cortex, and the left posterior part of the superior temporal gyrus. We suggest that these regions are part of a network involved in musical creation, and discuss their possible functional roles.

  9. Behavioral Quantification of Audiomotor Transformations in Improvising and Score-Dependent Musicians

    NARCIS (Netherlands)

    Harris, Robert; van Kranenburg, Peter; de Jong, Bauke M.

    2016-01-01

    The historically developed practice of learning to play a music instrument from notes instead of by imitation or improvisation makes it possible to contrast two types of skilled musicians characterized not only by dissimilar performance practices, but also disparate methods of audiomotor learning. I

  10. Behavioral Quantification of Audiomotor Transformations in Improvising and Score-Dependent Musicians.

    Science.gov (United States)

    Harris, Robert; van Kranenburg, Peter; de Jong, Bauke M

    2016-01-01

    The historically developed practice of learning to play a music instrument from notes instead of by imitation or improvisation makes it possible to contrast two types of skilled musicians characterized not only by dissimilar performance practices, but also disparate methods of audiomotor learning. In a recent fMRI study comparing these two groups of musicians while they either imagined playing along with a recording or covertly assessed the quality of the performance, we observed activation of a right-hemisphere network of posterior superior parietal and dorsal premotor cortices in improvising musicians, indicating more efficient audiomotor transformation. In the present study, we investigated the detailed performance characteristics underlying the ability of both groups of musicians to replicate music on the basis of aural perception alone. Twenty-two classically-trained improvising and score-dependent musicians listened to short, unfamiliar two-part excerpts presented with headphones. They played along or replicated the excerpts by ear on a digital piano, either with or without aural feedback. In addition, they were asked to harmonize or transpose some of the excerpts either to a different key or to the relative minor. MIDI recordings of their performances were compared with recordings of the aural model. Concordance was expressed in an audiomotor alignment score computed with the help of music information retrieval algorithms. Significantly higher alignment scores were found when contrasting groups, voices, and tasks. The present study demonstrates the superior ability of improvising musicians to replicate both the pitch and rhythm of aurally perceived music at the keyboard, not only in the original key, but also in other tonalities. Taken together with the enhanced activation of the right dorsal frontoparietal network found in our previous fMRI study, these results underscore the conclusion that the practice of improvising music can be associated with enhanced

  11. Neural correlates of lyrical improvisation: an FMRI study of freestyle rap.

    Science.gov (United States)

    Liu, Siyuan; Chow, Ho Ming; Xu, Yisheng; Erkkinen, Michael G; Swett, Katherine E; Eagle, Michael W; Rizik-Baer, Daniel A; Braun, Allen R

    2012-01-01

    The neural correlates of creativity are poorly understood. Freestyle rap provides a unique opportunity to study spontaneous lyrical improvisation, a multidimensional form of creativity at the interface of music and language. Here we use functional magnetic resonance imaging to characterize this process. Task contrast analyses indicate that improvised performance is characterized by dissociated activity in medial and dorsolateral prefrontal cortices, providing a context in which stimulus-independent behaviors may unfold in the absence of conscious monitoring and volitional control. Connectivity analyses reveal widespread improvisation-related correlations between medial prefrontal, cingulate motor, perisylvian cortices and amygdala, suggesting the emergence of a network linking motivation, language, affect and movement. Lyrical improvisation appears to be characterized by altered relationships between regions coupling intention and action, in which conventional executive control may be bypassed and motor control directed by cingulate motor mechanisms. These functional reorganizations may facilitate the initial improvisatory phase of creative behavior.

  12. Exploring improvisation in nursing.

    Science.gov (United States)

    Hanley, Mary Anne; Fenton, Mary V

    2007-06-01

    Improvisation has long been considered a function of music, dance, and the theatre arts. An exploration of the definitions and characteristics of this concept in relation to the art and practice of nursing provide an opportunity to illuminate related qualities within the field of nursing. Nursing has always demonstrated improvisation because it is often required to meet the needs of patients in a rapidly changing environment. However, little has been done to identify improvisation in the practice of nursing or to teach improvisation as a nursing knowledge-based skill. This article strives to explore the concept of improvisation in nursing, to describe the characteristics of improvisation as applied to nursing, and to utilize case studies to illustrate various manifestations of improvisation in nursing practice.

  13. Free Improvisation; Life Expression

    Science.gov (United States)

    Ng, Hoon Hong

    2011-01-01

    This autoethnographic study seeks the value, position and possibilities of free improvisation in the musical field. It explores how embodied knowledge, dialectical exchanges, emotional and intellectual stimulation constructs and reconstructs experiences in various contexts for the free improviser, who is both researcher and actual piano performer.…

  14. The Neuroscience of Improvisation

    Science.gov (United States)

    Landau, Andrew T.; Limb, Charles J.

    2017-01-01

    Current research in the neuroscience of musical creativity reveals promising implications for the value of learning to improvise. This article outlines the neuroscientific literature on musical improvisation and relates these findings to the benefits of musical creativity. We begin by describing the neural substrates of flow with respect to the…

  15. Music therapy improvisation

    Directory of Open Access Journals (Sweden)

    Mira Kuzma

    2001-09-01

    Full Text Available In this article, the technique of music therapy – music therapy improvisation is introduced. In this form of music therapy the improvising partners share meaning through the improvisation: the improvisation is not an end in itself: it portrays meaning that is personal, complex and can be shared with the partner. The therapeutic work, then, is meeting and matching the client's music in order to give the client an experience of "being known", being responded through sounds and being able to express things and communicate meaningfully. Rather than the client playing music, the therapy is about developing the engagement through sustained, joint improvisations. In music therapy, music and emotion share fundamental features: one may represent the other, i.e., we hear the music not as music but as dynamic emotional states. The concept of dynamic structure explains why music makes therapeutic sense.

  16. Using Jazz to Teach Improvisation

    Science.gov (United States)

    Chappell, Jon

    2007-01-01

    Improvising has been around since the dawn of music. Most music in the world is improvised to some extent, and the idea of performing notes on the page "as written" is a fairly young development in music's history. One genre that does heavily stress improvisation from the start is jazz. Since jazz ethic is based on improvised performances,…

  17. Using Jazz to Teach Improvisation

    Science.gov (United States)

    Chappell, Jon

    2007-01-01

    Improvising has been around since the dawn of music. Most music in the world is improvised to some extent, and the idea of performing notes on the page "as written" is a fairly young development in music's history. One genre that does heavily stress improvisation from the start is jazz. Since jazz ethic is based on improvised performances,…

  18. Expertise-related deactivation of the right temporoparietal junction during musical improvisation.

    Science.gov (United States)

    Berkowitz, Aaron L; Ansari, Daniel

    2010-01-01

    Musical training has been associated with structural changes in the brain as well as functional differences in brain activity when musicians are compared to nonmusicians on both perceptual and motor tasks. Previous neuroimaging comparisons of musicians and nonmusicians in the motor domain have used tasks involving prelearned motor sequences or synchronization with an auditorily presented sequence during the experiment. Here we use functional magnetic resonance imaging (fMRI) to examine expertise-related differences in brain activity between musicians and nonmusicians during improvisation--the generation of novel musical-motor sequences--using a paradigm that we previously used in musicians alone. Despite behaviorally matched performance, the two groups showed significant differences in functional brain activity during improvisation. Specifically, musicians deactivated the right temporoparietal junction (rTPJ) during melodic improvisation, while nonmusicians showed no change in activity in this region. The rTPJ is thought to be part of a ventral attentional network for bottom-up stimulus-driven processing, and it has been postulated that deactivation of this region occurs in order to inhibit attentional shifts toward task-irrelevant stimuli during top-down, goal-driven behavior. We propose that the musicians' deactivation of the rTPJ during melodic improvisation may represent a training-induced shift toward inhibition of stimulus-driven attention, allowing for a more goal-directed performance state that aids in creative thought.

  19. Interaction with Machine Improvisation

    Science.gov (United States)

    Assayag, Gerard; Bloch, George; Cont, Arshia; Dubnov, Shlomo

    We describe two multi-agent architectures for an improvisation oriented musician-machine interaction systems that learn in real time from human performers. The improvisation kernel is based on sequence modeling and statistical learning. We present two frameworks of interaction with this kernel. In the first, the stylistic interaction is guided by a human operator in front of an interactive computer environment. In the second framework, the stylistic interaction is delegated to machine intelligence and therefore, knowledge propagation and decision are taken care of by the computer alone. The first framework involves a hybrid architecture using two popular composition/performance environments, Max and OpenMusic, that are put to work and communicate together, each one handling the process at a different time/memory scale. The second framework shares the same representational schemes with the first but uses an Active Learning architecture based on collaborative, competitive and memory-based learning to handle stylistic interactions. Both systems are capable of processing real-time audio/video as well as MIDI. After discussing the general cognitive background of improvisation practices, the statistical modelling tools and the concurrent agent architecture are presented. Then, an Active Learning scheme is described and considered in terms of using different improvisation regimes for improvisation planning. Finally, we provide more details about the different system implementations and describe several performances with the system.

  20. The perception of musical spontaneity in improvised and imitated jazz performances

    Directory of Open Access Journals (Sweden)

    Annerose eEngel

    2011-05-01

    Full Text Available The ability to evaluate spontaneity in human behavior is called upon in the aesthetic appreciation of dramatic arts and music. The current study addresses the behavioral and brain mechanisms that mediate the perception of spontaneity in music performance. In a functional Magnetic Resonance Imaging experiment, 22 jazz musicians listened to piano melodies and judged whether they were improvised or imitated. Judgment accuracy (mean 55%; range 44-65%, which was low but above chance, was positively correlated with musical experience and empathy. Analysis of listeners’ hemodynamic responses revealed that amygdala activation was stronger for improvisations than imitations. This activation correlated with the variability of performance timing and intensity (loudness in the melodies, suggesting that the amygdala is involved in the detection of behavioral uncertainty. An analysis based on the subjective classification of melodies according to listeners’ judgments revealed that a network including the pre-supplementary motor area, frontal operculum, and anterior insula was most strongly activated for melodies judged to be improvised. This may reflect the increased engagement of an action simulation network when melodic predictions are rendered challenging due to perceived instability in the performer’s actions. Taken together, our results suggest that, while certain brain regions in skilled individuals may be generally sensitive to objective cues to spontaneity in human behavior, the ability to evaluate spontaneity accurately depends upon whether an individual’s action-related experience and perspective taking skills enable faithful internal simulation of the given behavior.

  1. The perception of musical spontaneity in improvised and imitated jazz performances.

    Science.gov (United States)

    Engel, Annerose; Keller, Peter E

    2011-01-01

    The ability to evaluate spontaneity in human behavior is called upon in the esthetic appreciation of dramatic arts and music. The current study addresses the behavioral and brain mechanisms that mediate the perception of spontaneity in music performance. In a functional magnetic resonance imaging experiment, 22 jazz musicians listened to piano melodies and judged whether they were improvised or imitated. Judgment accuracy (mean 55%; range 44-65%), which was low but above chance, was positively correlated with musical experience and empathy. Analysis of listeners' hemodynamic responses revealed that amygdala activation was stronger for improvisations than imitations. This activation correlated with the variability of performance timing and intensity (loudness) in the melodies, suggesting that the amygdala is involved in the detection of behavioral uncertainty. An analysis based on the subjective classification of melodies according to listeners' judgments revealed that a network including the pre-supplementary motor area, frontal operculum, and anterior insula was most strongly activated for melodies judged to be improvised. This may reflect the increased engagement of an action simulation network when melodic predictions are rendered challenging due to perceived instability in the performer's actions. Taken together, our results suggest that, while certain brain regions in skilled individuals may be generally sensitive to objective cues to spontaneity in human behavior, the ability to evaluate spontaneity accurately depends upon whether an individual's action-related experience and perspective taking skills enable faithful internal simulation of the given behavior.

  2. Keyboard Improvisation: A Phenomenological Study

    Science.gov (United States)

    Kingscott, John; Durrant, Colin

    2010-01-01

    The purpose of this study was to explore the phenomenon of musical improvisation within two contrasting musical genres--jazz piano and liturgical and concert organ. While improvisation is well documented in both genres, there is little literature relating the two forms and, in particular, the process of improvisation. The aim of this study is to…

  3. Intelligence and musical improvisation.

    Science.gov (United States)

    Hermelin, B; O'Connor, N; Lee, S; Treffert, D

    1989-05-01

    We investigated whether somebody with a severe mental impairment could not only remember and reproduce music, but was also able to generate it. Musical improvisation requires the ability to recognize constraints and also demands inventiveness. Musical improvisations on a traditional, tonal and also on a whole tone scale composition were produced by a mentally handicapped and by a normal control musician. It was found that not only the control but also the handicapped subject could improvise appropriately within structural constraints, although with the tonal music the idiot-savant showed some stylistic latitude. It is concluded that cognitive processes such as musical input analysis, decision making, and output monitoring are independent of general intellectual status.

  4. The Effects of Group Free Improvisation Instruction on Improvisation Achievement and Improvisation Confidence

    Science.gov (United States)

    Hickey, Maud; Ankney, Kimberly; Healy, Daniel; Gallo, Donna

    2016-01-01

    While improvisation in K-12 schools in the USA has gained some traction since the inception of the US National Standards in 1994, there is still a dearth of improvisation activities in schools because of the lack of music teacher preparation in improvisation. The purpose of this study was to determine if providing group free improvisation…

  5. Narrative Development in Improvisational Theatre

    Science.gov (United States)

    Baumer, Allan; Magerko, Brian

    We have investigated the experience of improvisers as they perform to better understand how narrative is constructed by group performance in improvisational theatre. Our study was conducted with improvisers who would perform improv "games" with each iteration video recorded. Each individual participant was shown the video in a retrospective protocol collection, before reviewing it again in a group interview. This process is meant to elicit information about how the cognition involved develops narrative during an improvisation performance. This paper presents our initial findings related to narrative development in improvisational theatre with an ambition to use these and future analyses in creating improvisational intelligent agents. These findings have demonstrated that the construction of narrative is crafted through the making and accepting of scene-advancing offers, which expert improvisers are more readily capable of performing.

  6. Dalcroze-Based Improvisation.

    Science.gov (United States)

    Abramson, Robert M.

    1980-01-01

    Described is the Emile Jaques-Dalcroze method of improvisation, which he believed was the study of the direct relations between cerebral commands and muscular interpretations in order to express one's own musical feelings. Performance is propelled by developing the students' powers of sensation, imagination, and memory. (Author/KC)

  7. Orff-Based Improvisation.

    Science.gov (United States)

    Thomas, Judith

    1980-01-01

    Described are improvisational activities based on the Orff-Schulwerk teaching technique which include: sound and movement; sound and movement plus visuals; interpretation of designs from nature, architecture, paintings, rotating rondo, singing hands, and moving from words to song. Pictures of children participating in these activities are…

  8. Generation of novel motor sequences: the neural correlates of musical improvisation.

    Science.gov (United States)

    Berkowitz, Aaron L; Ansari, Daniel

    2008-06-01

    While some motor behavior is instinctive and stereotyped or learned and re-executed, much action is a spontaneous response to a novel set of environmental conditions. The neural correlates of both pre-learned and cued motor sequences have been previously studied, but novel motor behavior has thus far not been examined through brain imaging. In this paper, we report a study of musical improvisation in trained pianists with functional magnetic resonance imaging (fMRI), using improvisation as a case study of novel action generation. We demonstrate that both rhythmic (temporal) and melodic (ordinal) motor sequence creation modulate activity in a network of brain regions comprised of the dorsal premotor cortex, the rostral cingulate zone of the anterior cingulate cortex, and the inferior frontal gyrus. These findings are consistent with a role for the dorsal premotor cortex in movement coordination, the rostral cingulate zone in voluntary selection, and the inferior frontal gyrus in sequence generation. Thus, the invention of novel motor sequences in musical improvisation recruits a network of brain regions coordinated to generate possible sequences, select among them, and execute the decided-upon sequence.

  9. Descriptions of Improvisational Thinking by Developing Jazz Improvisers

    Science.gov (United States)

    Norgaard, Martin

    2017-01-01

    Research investigating improvisational skill development in adolescent learners is scant. In this study interviews with developing jazz improvisers are used to characterize the skill-building process. The findings were considered in light of two views of skill learning. In one view, students progress through several discrete levels, while in a…

  10. Investigations on the magnetization behavior of magnetic composite particles

    Science.gov (United States)

    Eichholz, Christian; Knoll, Johannes; Lerche, Dietmar; Nirschl, Hermann

    2014-11-01

    In life sciences the application of surface functionalized magnetic composite particles is establishing in diagnostics and in downstream processing of modern biotechnology. These magnetic composite particles consist of non-magnetic material, e.g. polystyrene, which serves as a matrix for the second magnetic component, usually colloidal magnetite. Because of the multitude of magnetic cores these magnetic beads show a complex magnetization behavior which cannot be described with the available approaches for homogeneous magnetic material. Therefore, in this work a new model for the magnetization behavior of magnetic composite particles is developed. By introducing an effective magnetization and considering an overall demagnetization factor the deviation of the demagnetization of homogeneously magnetized particles is taken into account. Calculated and experimental results show a good agreement which allows for the verification of the adapted model of particle magnetization. Besides, a newly developed magnetic analyzing centrifuge is used for the characterization of magnetic composite particle systems. The experimental results, also used for the model verification, give both, information about the magnetic properties and the interaction behavior of particle systems. By adding further components to the particle solution, such as salts or proteins, industrial relevant systems can be reconstructed. The analyzing tool can be used to adapt industrial processes without time-consuming preliminary tests with large samples in the process equipments.

  11. Improvisation in Latin American Musics.

    Science.gov (United States)

    Behague, Gerard

    1980-01-01

    Improvisation implies a relative freedom to choose elements within stylistic norms of rules proper to a given culture. Improvisatory processes for music from several cultures are described. These cultures are: Indian, Spanish, African, and Afro-Cuban (rumba). A few resources focusing on improvisation in Latin American music are presented. (KC)

  12. Improvisation: Thinking "and" Playing Music

    Science.gov (United States)

    Beckstead, David

    2013-01-01

    This article explores and contextualizes improvisation in music from an educational perspective. First, recent brain research that sees improvisation as a distinct cognitive activity is examined and used to illustrate the importance and uniqueness of this often ignored area of music learning. Next, the implications for the music classroom are…

  13. Improvisation: Thinking "and" Playing Music

    Science.gov (United States)

    Beckstead, David

    2013-01-01

    This article explores and contextualizes improvisation in music from an educational perspective. First, recent brain research that sees improvisation as a distinct cognitive activity is examined and used to illustrate the importance and uniqueness of this often ignored area of music learning. Next, the implications for the music classroom are…

  14. Improvisation and meaning.

    Science.gov (United States)

    Gilbertson, Simon

    2013-08-07

    This article presents and discusses a long-term repeated-immersion research process that explores meaning allocated to an episode of 50 seconds of music improvisation in early neurosurgical rehabilitation by a teenage boy with severe traumatic brain injury and his music therapist. The process began with the original therapy session in August 1994 and extends to the current time of writing in 2013. A diverse selection of qualitative research methods were used during a repeated immersion and engagement with the selected episodes. The multiple methods used in this enquiry include therapeutic narrative analysis and musicological and video analysis during my doctoral research between 2002 and 2004, arts-based research in 2008 using expressive writing, and arts-based research in 2012 based on the creation of a body cast of my right hand as I used it to play the first note of my music improvising in the original therapy episode, which is accompanied by reflective journaling. The casting of my hand was done to explore and reconsider the role of my own body as an embodied and integral, but originally hidden, part of the therapy process. Put together, these investigations explore the potential meanings of the episode of music improvisation in therapy in an innovative and imaginative way. However, this article does not aim at this stage to present a model or theory for neurorehabilitation but offers an example of how a combination of diverse qualitative methods over an extended period of time can be instrumental in gaining innovative and rich insights into initially hidden perspectives on health, well-being, and human relating.

  15. Improvisation as Ability, Culture, and Experience

    Science.gov (United States)

    Higgins, Lee; Mantie, Roger

    2013-01-01

    We argue in this article for greater role for improvisation in the music classroom. Based on an extensive examination of scholarship about improvisational practices, we propose three conceptualizations--ability, culture, experience--that can serve to guide the teaching of improvisation. When considered as an "ability," improvisation is a…

  16. Improvisation in Action

    DEFF Research Database (Denmark)

    Bansler, Jørgen P.; Havn, Erling C.

    2003-01-01

    The paper discusses the role of extemporaneous action and bricolage in designing and implementing information systems in organizations. We report a longitudinal field study of design and implementation of a Web-based groupware application in a multinational corporation. We adopt a sensemaking...... perspective to analyze the dynamics of this process and show that improvisational action and bricolage (making do with the materials at hand) played a vital role in the development of the application. Finally, we suggest that this case study provides an occasion to reconsider how we conceptualize information...

  17. Vocal Improvisation for Elementary Students.

    Science.gov (United States)

    Thompson, Keith P.

    1980-01-01

    The author describes the three-phase process of musical creativity (exploratory, invention, organizational), identifying activities in each of the creative phases. Included are vocal impression, picture sounds, chord tones, and name improvisation. Selected readings and recordings are included. (KC)

  18. Improvisation skills for clinical work

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    Creativity and flexibility are the hallmarks of effective improvisational technique. It is also becoming increasingly apparent that providing musical structure can be significant in enabling clients with poor communication, reciprocity and resistance to engagement. This workshop will offer some...

  19. Keywords in musical free improvisation

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2017-01-01

    This article presents some keywords and concepts concerning free improvised music and its recent developments drawing from ongoing bibliographical research. A radical pluralism stems from musicians' backgrounds and the mixtures and fusions of styles and idioms resulting from these mixtures....... Seemingly very different "performance-driven" and "playdriven" attitudes exist, even among musicians who share the practice of performing at concerts. New models of musical analysis aiming specifically at free improvised music provide strategical observations of interaction and structure....

  20. Pedagogical applications of cognitive research on musical improvisation.

    Science.gov (United States)

    Biasutti, Michele

    2015-01-01

    This paper presents a model for the implementation of educational activities involving musical improvisation that is based on a review of the literature on the psychology of music. Psychology of music is a complex field of research in which quantitative and qualitative methods have been employed involving participants ranging from novices to expert performers. The cognitive research has been analyzed to propose a pedagogical approach to the development of processes rather than products that focus on an expert's use of improvisation. The intention is to delineate a reflective approach that goes beyond the mere instruction of some current practices of teaching improvisation in jazz pedagogy. The review highlights that improvisation is a complex, multidimensional act that involves creative and performance behaviors in real-time in addition to processes such as sensory and perceptual encoding, motor control, performance monitoring, and memory storage and recall. Educational applications for the following processes are outlined: anticipation, use of repertoire, emotive communication, feedback, and flow. These characteristics are discussed in relation to the design of a pedagogical approach to musical improvisation based on reflection and metacognition development.

  1. Pedagogical applications of cognitive research on musical improvisation

    Science.gov (United States)

    Biasutti, Michele

    2015-01-01

    This paper presents a model for the implementation of educational activities involving musical improvisation that is based on a review of the literature on the psychology of music. Psychology of music is a complex field of research in which quantitative and qualitative methods have been employed involving participants ranging from novices to expert performers. The cognitive research has been analyzed to propose a pedagogical approach to the development of processes rather than products that focus on an expert’s use of improvisation. The intention is to delineate a reflective approach that goes beyond the mere instruction of some current practices of teaching improvisation in jazz pedagogy. The review highlights that improvisation is a complex, multidimensional act that involves creative and performance behaviors in real-time in addition to processes such as sensory and perceptual encoding, motor control, performance monitoring, and memory storage and recall. Educational applications for the following processes are outlined: anticipation, use of repertoire, emotive communication, feedback, and flow. These characteristics are discussed in relation to the design of a pedagogical approach to musical improvisation based on reflection and metacognition development. PMID:26029147

  2. Pedagogical applications of the cognitive research on music improvisation

    Directory of Open Access Journals (Sweden)

    MIchele eBiasutti

    2015-05-01

    Full Text Available This paper presents a model for the implementation of educational activities involving musical improvisation that is based on a review of the literature on the psychology of music. Psychology of music is a complex field of research in which quantitative and qualitative methods have been employed involving participants ranging from novices to expert performers. The cognitive research has been analyzed to propose a pedagogical approach to the development of processes rather than products that focus on an expert’s use of improvisation. The intention is to delineate a reflective approach that goes beyond the mere instruction of some current practices of teaching improvisation in jazz pedagogy. The review highlights that improvisation is a complex, multidimensional act that involves creative and performance behaviors in real-time in addition to processes such as sensory and perceptual encoding, motor control, performance monitoring, and memory storage and recall. Educational applications for the following processes are outlined: anticipation, use of repertoire, emotive communication, feedback and flow. These characteristics are discussed in relation to the design of a pedagogical approach to musical improvisation based on reflection and metacognition development.

  3. Ready to improvise?

    CERN Multimedia

    2008-01-01

    Quite unusually for a CERN colloquium, on 8 and 9 August the CERN Auditorium will host a presentation on comedy and communication and a workshop by Charna Halpern, the founder of "iO theaters" in Chicago and Los Angeles. Members of Geneva’s Impro Federation (FIG) in full swing!Charna Halpern has been teaching performers how to work together for more than 20 years. She founded the world-famous iO theaters (formerly Improv Olympic) in Chicago and Los Angeles in 1981. Today, the theatres are the meccas of training in the art of improvisation, and they act as a "recruiting" stop for television shows supplying New York and Hollywood with writers and performers. Specializing in creating a "group mind" with hilarious end results, Charna Halpern will be sharing her secrets and skills with the CERN audience and she will make her public laugh as they learn. The following day, Saturday, she will give a workshop on how to prepare an improv gro...

  4. Improvisational Practices in Elementary General Music Classrooms

    Science.gov (United States)

    Gruenhagen, Lisa M.; Whitcomb, Rachel

    2014-01-01

    Despite historic and ongoing support for the inclusion of improvisation in the elementary general music curriculum, music educators consistently report challenges with implementation of improvisational activities in their classes. This study was designed to examine (a) the extent to which improvisational activities were occurring in the…

  5. Magnetic behavior of Pd nanoclusters

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera-Granja, F. [Instituto de Fisica ' Manuel Sandoval Vallarta' , Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, S.L.P. (Mexico)]. E-mail: faustino@dec1.ifisica.uaslp.mx; Montejano-Carrizales, J.M. [Instituto de Fisica ' Manuel Sandoval Vallarta' , Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, S.L.P. (Mexico); Berlanga-Ramirez, E.O. [Instituto de Fisica ' Manuel Sandoval Vallarta' , Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, S.L.P. (Mexico); Vega, A. [Departamento de Fisica Teorica, Atomica, Nuclear y Optica, Universidad de Valladolid, E-47011 Valladolid (Spain)

    2004-12-31

    We study the magnetic properties of free-standing Pd clusters of some selected sizes with icosahedral structures which are obtained as the most stable ones using the Embedded Atom Method from an uniform relaxation of different geometrical configurations. The spin-polarized electronic structure and related magnetic properties of those optimized geometries were calculated by solving self-consistently a spd tight-binding Hamiltonian. The magnetic moments obtained in our calculations present a step-like dependence as a function of the exchange parameter in the case of small cluster sizes and a more complex dependence for larger cluster sizes is found. We discuss the results in comparison with previous calculations for FCC Pd clusters and with recent experimental findings. We also study the dependence of the magnetic moments distribution within the clusters with some geometrical effects such as hydrostatic deformations and twining.

  6. Improvisation and the self-organization of multiple musical bodies.

    Directory of Open Access Journals (Sweden)

    Ashley eWalton

    2015-04-01

    Full Text Available Understanding everyday behavior relies heavily upon understanding our ability to improvise, how we are able to continuously anticipate and adapt in order to coordinate with our environment and others. Here we consider the ability of musicians to improvise, where they must spontaneously coordinate their actions with co-performers in order to produce novel musical expressions. Investigations of this behavior have traditionally focused on describing the organization of cognitive structures. The focus, here, however, is on the ability of the time-evolving patterns of inter-musician movement coordination as revealed by the mathematical tools of complex dynamical systems to provide a new understanding of what potentiates the novelty of spontaneous musical action. We demonstrate this approach through the application of cross wavelet spectral analysis, which isolates the strength and patterning of the behavioral coordination that occurs between improvising musicians across a range of nested time-scales. Revealing the sophistication of the previously unexplored dynamics of movement coordination between improvising musicians is an important step towards understanding how creative musical expressions emerge from the spontaneous coordination of multiple musical bodies.

  7. Using Jazz as a Metaphor to Teach Improvisational Communication Skills

    Directory of Open Access Journals (Sweden)

    Paul Haidet

    2017-08-01

    Full Text Available Metaphor helps humans understand complex concepts by “mapping” them onto accessible concepts. The purpose of this study was to investigate the effects of using jazz as a metaphor to teach senior medical students improvisational communication skills, and to understand student learning experiences. The authors designed a month-long course that used jazz to teach improvisational communication. A sample of fourth-year medical students (N = 30 completed the course between 2011 and 2014. Evaluation consisted of quantitative and qualitative data collected pre- and post-course, with comparison to a concurrent control group on some measures. Measures included: (a Student self-reports of knowledge and ability performing communicative tasks; (b blinded standardized patient assessment of students’ adaptability and quality of listening; and (c qualitative course evaluation data and open-ended interviews with course students. Compared to control students, course students demonstrated statistically significant and educationally meaningful gains in adaptability and listening behaviors. Students’ course experiences suggested that the jazz components led to high engagement and creativity, and provided a model to guide application of improvisational concepts to their own communication behaviors. Metaphor proved to be a powerful tool in this study, partly through enabling increased reflection and decreased resistance to behaviors that, on the surface, tended to run counter to generally accepted norms. The use of jazz as a metaphor to teach improvisational communication warrants further refinement and investigation.

  8. Using Jazz as a Metaphor to Teach Improvisational Communication Skills.

    Science.gov (United States)

    Haidet, Paul; Jarecke, Jodi; Yang, Chengwu; Teal, Cayla R; Street, Richard L; Stuckey, Heather

    2017-08-04

    Metaphor helps humans understand complex concepts by "mapping" them onto accessible concepts. The purpose of this study was to investigate the effects of using jazz as a metaphor to teach senior medical students improvisational communication skills, and to understand student learning experiences. The authors designed a month-long course that used jazz to teach improvisational communication. A sample of fourth-year medical students (N = 30) completed the course between 2011 and 2014. Evaluation consisted of quantitative and qualitative data collected pre- and post-course, with comparison to a concurrent control group on some measures. Measures included: (a) Student self-reports of knowledge and ability performing communicative tasks; (b) blinded standardized patient assessment of students' adaptability and quality of listening; and (c) qualitative course evaluation data and open-ended interviews with course students. Compared to control students, course students demonstrated statistically significant and educationally meaningful gains in adaptability and listening behaviors. Students' course experiences suggested that the jazz components led to high engagement and creativity, and provided a model to guide application of improvisational concepts to their own communication behaviors. Metaphor proved to be a powerful tool in this study, partly through enabling increased reflection and decreased resistance to behaviors that, on the surface, tended to run counter to generally accepted norms. The use of jazz as a metaphor to teach improvisational communication warrants further refinement and investigation.

  9. Improvisation and the self-organization of multiple musical bodies

    Science.gov (United States)

    Walton, Ashley E.; Richardson, Michael J.; Langland-Hassan, Peter; Chemero, Anthony

    2015-01-01

    Understanding everyday behavior relies heavily upon understanding our ability to improvise, how we are able to continuously anticipate and adapt in order to coordinate with our environment and others. Here we consider the ability of musicians to improvise, where they must spontaneously coordinate their actions with co-performers in order to produce novel musical expressions. Investigations of this behavior have traditionally focused on describing the organization of cognitive structures. The focus, here, however, is on the ability of the time-evolving patterns of inter-musician movement coordination as revealed by the mathematical tools of complex dynamical systems to provide a new understanding of what potentiates the novelty of spontaneous musical action. We demonstrate this approach through the application of cross wavelet spectral analysis, which isolates the strength and patterning of the behavioral coordination that occurs between improvising musicians across a range of nested time-scales. Revealing the sophistication of the previously unexplored dynamics of movement coordination between improvising musicians is an important step toward understanding how creative musical expressions emerge from the spontaneous coordination of multiple musical bodies. PMID:25941499

  10. Improvisation and the self-organization of multiple musical bodies.

    Science.gov (United States)

    Walton, Ashley E; Richardson, Michael J; Langland-Hassan, Peter; Chemero, Anthony

    2015-01-01

    Understanding everyday behavior relies heavily upon understanding our ability to improvise, how we are able to continuously anticipate and adapt in order to coordinate with our environment and others. Here we consider the ability of musicians to improvise, where they must spontaneously coordinate their actions with co-performers in order to produce novel musical expressions. Investigations of this behavior have traditionally focused on describing the organization of cognitive structures. The focus, here, however, is on the ability of the time-evolving patterns of inter-musician movement coordination as revealed by the mathematical tools of complex dynamical systems to provide a new understanding of what potentiates the novelty of spontaneous musical action. We demonstrate this approach through the application of cross wavelet spectral analysis, which isolates the strength and patterning of the behavioral coordination that occurs between improvising musicians across a range of nested time-scales. Revealing the sophistication of the previously unexplored dynamics of movement coordination between improvising musicians is an important step toward understanding how creative musical expressions emerge from the spontaneous coordination of multiple musical bodies.

  11. Improvisation: Performer as Co-composer

    Directory of Open Access Journals (Sweden)

    Kyle Schick

    2012-05-01

    Full Text Available Elements of musical improvisation have been present throughout the medieval, renaissance, and baroque eras, however, improvisation had the most profound recorded presence in the baroque era. Improvisation is inherently a living practice and leaves little documentation behind for historians to study, but however elusive, it is still important to trace where instances of this improvised art appear throughout the eras listed above. It is also interesting to trace what role improvisation would later have in realizing the Baroque ideals of emotional expression, virtuosity, and individuality. This paper seeks to focus on a few of the best documented mediums of improvisation within each era. During the medieval period, improvisation took on the form of improvised counterpoint against a plainsong. In the renaissance, improvised harmony of faburden and the contenance angloise is this paper’s selected example. In the Baroque, this study seeks to describe several areas where improvisation appears such as the art of improvised accompaniment from figured bass symbols, the practice of expressive ornamentation on a written melody, and improvised vocal embellishments and cadenzas of the da capo aria. A final aim of this research is to provide examples to clarify the definition of improvisation as the degree to which the composer of a musical work has given control of its realization to the performer. Treatises and ear witness accounts of improvised musical forms provided primary sources. Other sources used in this research included writings on performance practices of different historical eras and writings on the changing relationship between the composer and the performer. This paper also consults writings on how improvised music was perceived historically as opposed to composed music.

  12. Improvisation skills for clinical work

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    based on a short theme or ‘leit-motif’ will all be included in the workshop activities, using both piano, and other instruments. While interventions utilising improvisational music therapy should never be driven by clinical procedures, applying therapeutic method, and also recognising method...

  13. Developing clinical piano improvisation skills

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    2003-01-01

    Teaching piano improvisation skills for use in clinical work relies on the development of a range of musical techniques and therapeutic methods that are combined and integrated. Simple musical styles of playing such as melody dialogues, two chord accompaniments, walking basses (tonal and atonal), 6...

  14. Body memories in dance improvisation

    DEFF Research Database (Denmark)

    Ravn, Susanne

    In the analysis of body-memory and improvisation presented in this paper I contend that dancers’ specialised body-memory are not to be understood as more or less automatized. Rather, in each repetition, body-memories – or habits – are to be understood as unfolding in response to the actual contex...

  15. Improvisation, change, works and ragas

    NARCIS (Netherlands)

    van der Meer, W.

    2008-01-01

    Studying change in music poses considerable challenges. Especially with respect to music that is not, or only partly, written, and improvised music in which the line between ‘fixed’ and ‘free’ is extremely fine. Where does internal variability turn into a breach with the established tradition? This

  16. Improvisation, change, works, and ragas

    NARCIS (Netherlands)

    van der Meer, W.

    2008-01-01

    Studying change in music poses considerable challenges. Especially with respect to music that is not, or only partly, written, and improvised music in which the line between 'fixed' and 'free' is extremely fine. Where does internal variability turn into a breach with the established tradition? This

  17. Improvisation as a Way of Knowing Music

    DEFF Research Database (Denmark)

    Olsen, Jens Skou

    -based classes put together with little or no regard to instrumentation and genre with a strong focus on analysis, artistic reflection and evaluation of the individual output. The author examines improvisation as an adaptation to and transformation of the world, and the possibility of a methodology......This paper examines improvisation and points to improvisational practice as the central transforming force in music and the educational practice of the Rhythmic Music Conservatory (RMC). In less than 25 years RMC has radically changed its education methodology from one based on jazz and African...... of improvisation in popular music that can inform the construction of meaningful and relevant popular music programs based on music improvisation is discussed. The author argues for a need to critically examine the tacit auxiliary hypotheses that seem to govern our understanding of musical improvisation through...

  18. Novice Music Teachers Learning to Improvise in an Improvisation Professional Development Workshop

    Science.gov (United States)

    Filsinger, Mark H.

    2013-01-01

    With the intent of improving music improvisation pedagogy, the purpose of this research was to examine experiences of six novice music teachers and a professional development facilitator in an eight-week Improvisation Professional Development Workshop (IPDW). The research questions were: 1. How do teachers learn to improvise within the context of…

  19. Improvisational choreography in teleservice work.

    Science.gov (United States)

    Whalen, Jack; Whalen, Marilyn; Henderson, Kathryn

    2002-06-01

    This naturalistic study of the ordinary work practice of sales representatives employed by the call centre of a large office-equipment company focuses on the actions of those sales reps during their calls with customers. We show how this work performance is organized through an improvisational choreography of action involving not only the turn-by-turn interchange with customers on the telephone but also the concurrent utilization of a variety of tools and artefacts. While 'improvise' and 'choreograph' may appear to be conceptually incongruent, our analysis demonstrates that even though these teleservice workers recurrently fabricate their actions out of materials and means that are conveniently on hand, the convenience is often carefully arranged to afford such extemporaneous composition. Finally, we conclude from this analysis that the traditional topics of 'work routines' and 'routinization' need to be respecified in order to take into account how any 'routine' is a contingently produced result (and in this centre, a craft-like performance).

  20. Probing the magnetic behavior of single nanodots.

    Science.gov (United States)

    Neumann, Alexander; Thönnissen, Carsten; Frauen, Axel; Hesse, Simon; Meyer, Andreas; Oepen, Hans Peter

    2013-05-08

    In this paper, a method is presented that has the sensitivity to measure magnetization behavior of single nanostructures. It is demonstrated that the technique gives the ability to separate different signals of single nanodots from a small ensemble of structures. Our method is based on the anomalous Hall-Effect and allows for resolving signals from spherical nanoparticles with diameter down to 3.5 nm. The method gives access to magnetic properties of particles in a wide thermal and dynamical range. The potential of the technique is demonstrated utilizing particles that are created from Co films sandwiched by Pt layers.

  1. Design and transient behavior of magnetic gears

    Science.gov (United States)

    Zheng, Ping; Bai, Jingang; Lin, Jia; Fu, Zhenxing; Song, Zhiyi; Lin, Fei

    2014-05-01

    The torque density is a key factor for magnetic gears. To obtain maximum torque density, the design principle of magnetic gears is proposed and the maximum transmitting torque is investigated under different combinations of the inner and outer permanent magnets (PM) rotor pole pairs. The research proves that the maximum transmitting torque and the minimum torque ripple can be obtained only when the ratio of the outer and inner PM pole pair numbers is fractional. Then, the optimal selection of the span ratio and thickness of magnetic blocks in the stationary modulating ring is investigated to obtain the maximum torque. Meanwhile, analyses of the losses of various parts in the magnetic gear show that the loss of the PMs is about 70% of the total losses. Therefore, the method of dividing the PM into several pieces along the circumferential direction is employed to reduce the PM loss, which makes the PM loss reduced by 73%. Additionally, the transient behavior of the magnetic gear is analyzed, indicating that the lower torsional stiffness is the main reason for oscillations during transient changes in speed and load. To suppress oscillations due to transients, damper windings are employed and the transient time and the maximum oscillation amplitude are reduced by 25% and 20%, respectively.

  2. Glassy behavior in magnetic fine particles

    CERN Document Server

    Muro, M G D; Labarta, A

    2000-01-01

    A detailed study of the static and dynamic magnetic properties of nanocrystalline barium hexaferrite powder was done. Particles of about 10 nm diameter exhibit the main features attributed to glassy behavior. Different results make evident the presence of strong interactions in the studied system. This glassy state is mostly attributed to the frustration induced by magnetic interactions between randomly distributed particles, although the surface spins contribution cannot be discarded. The effective energy barrier distribution obtained from the analysis of the time dependence of the thermoremanence in terms of the T ln (t/tau sub 0) scaling shows a maximum located at energies higher than the mean anisotropy energy barrier. When doing the relaxation experiments after field cooling at increasing fields, the obtained effective energy distribution progressively resembles the anisotropy energy distribution. Therefore, we demonstrate how the glassy state can be erased by applying a magnetic field.

  3. Experimental improvisation practise and notation. Addenda 2000-

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    Addenda to Experimental improvisation practise and notation (please see this title for more information!) Stichwörter: experimentelle Musik, offenes Werk, grafische Notation, musikalische Notation, musikalische Aufführungspraxis, freie Improvisation, Musikpädagogik, Geschichte der Musik, Musikäst...

  4. Experimental improvisation practise and notation. Addenda 2000-

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    Addenda to Experimental improvisation practise and notation (please see this title for more information!) Stichwörter: experimentelle Musik, offenes Werk, grafische Notation, musikalische Notation, musikalische Aufführungspraxis, freie Improvisation, Musikpädagogik, Geschichte der Musik, Musikäst...

  5. Improvisation: Another Way to Move and Dance

    Science.gov (United States)

    Morgan, Rachel

    2004-01-01

    Using improvisation in movement and dance classes is an ideal way to help students relate to how their bodies move. Students can learn confidence from the way they move by experimenting with unconventional and different methods. Improvisation, as such, is responding spontaneously to stimuli (music) in order to create a composition that allows for…

  6. Informal Music Learning, Improvisation and Teacher Education

    Science.gov (United States)

    Wright, Ruth; Kanellopoulos, Panagiotis

    2010-01-01

    This paper explores firstly the sense in which improvisation might be conceived of as an informal music education process and, secondly, the effects of a course in free improvisation on student teachers' perceptions in relation to themselves as musicians, music as a school subject and children as musicians. The results of a study conducted in two…

  7. A Longitudinal Study of Selected Characteristics of Children's Melodic Improvisations

    Science.gov (United States)

    Brophy, Timothy S.

    2005-01-01

    This study is an examination of the melodic improvisations of a group of children (N = 62) for 3 years, from ages 7 through 9. Participants improvised as part of a class rondo for Orff instruments, in ABACADA form, in which the B, C, and D sections were 8-measure alto-xylophone improvisations in C pentatonic. Each participant improvised three…

  8. Dynamic Interplay in Clinical Improvisation

    Directory of Open Access Journals (Sweden)

    Mercédès Pavlicevic

    2002-07-01

    Full Text Available I would like to begin by examining the title, since this will clarify the theoretical framework within which this paper will develop. Chambers Dictionary (1988 defines dynamic as relating to force; activity or things in motion; forms or patterns of growth or change; any driving force instrumental in growth or change. The word interplay refers to the reciprocal, mutual musical interaction between therapist and patient. Both players' contributions help to clarify the quality of the emotional interaction in the musical relationship. The concept of clinical improvisation in music therapy is best illustrated by a detour via the literature of mother-infant interaction.

  9. Developing clinical piano improvisation skills

    DEFF Research Database (Denmark)

    Wigram, Anthony Lewis

    2003-01-01

    Teaching piano improvisation skills for use in clinical work relies on the development of a range of musical techniques and therapeutic methods that are combined and integrated. Simple musical styles of playing such as melody dialogues, two chord accompaniments, walking basses (tonal and atonal), 6...... in a new direction. Structure and lack of structure play a balanced role in the clinical process, and reflects the skills of the therapist to musically meet the needs of the client. This workshop will provide teaching and practice tools for the participants that are intended to sustain the creativity...

  10. Magnetic behavior of biosynthesized Co3O4 nanoparticles

    Science.gov (United States)

    Diallo, A.; Doyle, T. B.; Mothudi, B. M.; Manikandan, E.; Rajendran, V.; Maaza, M.

    2017-02-01

    This contribution reports for the 1st time on the magnetic behavior of CO3O4 nanoparticles synthesized by a "green" process using an Aspalathus linearis' leaves natural extract. More accurately magnetic behavior of CO3O4 nanoparticles successfully biosynthesized was investigated using vibrating sample magnetometer. The magnetization behavior for the samples manifests a combination of size dependent antiferromagnetic and paramagnetic behaviors, respectively, for the core and shell of the nanoparticles.

  11. Pluralism in contemporary improvised concert music

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2002-01-01

    Pluralist musical practise in improvised music yield inspiring models of music as a medium for human co-existence. Active music therapy in its modern form came into being on the background of emancipative tendencies in the mid-sixties and on which questioned traditional concepts of authority....... In Western music cultures, both serious and popular, there was a strongly renewed interest in improvisation. Especially from around 1980, formerly clear boundaries between "serious" and "popular" were taken away as a result of these developments. Even though music therapists are often unaware of its...... existence, an improvised concert music has existed ever since in many cities and deserves our serious interest. Much valuable experience within the medium of free improvisation has been gained here, and a lot of music has been recorded on LP, cassette and CD. There is also a growing body of litterature...

  12. Improvisation during Process-Technology Adoption

    DEFF Research Database (Denmark)

    Tjørnehøj, Gitte; Mathiassen, Lars

    2010-01-01

    SPI technology adoption and events that causes the process to drift in unpredictable directions. To further understand how management's attempt to control the process is complemented by drifting, this article investigates the role of improvisation in adoption of SPI technology in a Danish software...... firm, SmallSoft, over a 10-year period (1996-2005). We found that micro-level and macro-level improvisations interacted, often in uncoordinated ways, to shape SPI technology adoption at SmallSoft. The improvisations enhanced employee creativity, motivation and empowerment, created momentum...... in the adoption process despite constrained resources, and, most importantly, helped adapt SPI technology to the everyday practices at SmallSoft. However, we also identified un-called for improvisations and outcomes that were uncoordinated with SmallSoft's goals. Based on these findings we discuss how management...

  13. Instrumental Jazz Improvisation Development: Characteristics of Novice, Intermediate, and Advanced Improvisers

    Science.gov (United States)

    Palmer, C. Michael

    2016-01-01

    The purpose of this exploratory study was to examine the role aural imitation ability, jazz theory knowledge, and personal background variables play in the development of jazz improvisation achievement. Participants (N = 70) included 26 high school and 44 college instrumentalists with varying degrees of jazz improvisation experience. Data were…

  14. Instrumental Jazz Improvisation Development: Characteristics of Novice, Intermediate, and Advanced Improvisers

    Science.gov (United States)

    Palmer, C. Michael

    2016-01-01

    The purpose of this exploratory study was to examine the role aural imitation ability, jazz theory knowledge, and personal background variables play in the development of jazz improvisation achievement. Participants (N = 70) included 26 high school and 44 college instrumentalists with varying degrees of jazz improvisation experience. Data were…

  15. Fearless Improvisation: A Pilot Study to Analyze String Students' Confidence, Anxiety, and Attitude toward Learning Improvisation

    Science.gov (United States)

    Alexander, Michael L.

    2012-01-01

    The purpose of this study was to investigate the confidence, anxiety, and attitude of novice string student improvisers. A form of the Fennema-Sherman Mathematics Attitudes Scales, as modified for improvisation by Wehr-Flowers, was given to middle school and high school string students (N = 121) after their participation in a 4-month improvisation…

  16. Can Improvisation Be "Taught"?: A Call for Free Improvisation in Our Schools

    Science.gov (United States)

    Hickey, Maud

    2009-01-01

    The purpose of this article is to present the idea that the music education profession's current drive to include improvisation in school music is limited in its approach, and that "teaching" improvisation, in the traditional sense, is not possible. These beliefs are based on an examination of current methodologies and texts in light of the…

  17. Biography, Identity, Improvisation, Sound: Intersections of Personal and Social Identity through Improvisation

    Science.gov (United States)

    Smilde, Rineke

    2016-01-01

    This essay addresses the relationship of improvisation and identity. Biographical research that was conducted by the author into professional musicians' lifelong learning showed the huge importance of improvisation for personal expression. Musically, the concept of "sound" appeared to serve as a strong metaphor for identity. In addition,…

  18. What makes a good musical improviser? An expert view on improvisational expertise

    NARCIS (Netherlands)

    Wopereis, Iwan; Kirschner, Paul A.; Van Merriënboer, Jeroen

    2012-01-01

    Wopereis, I. G. J. H., Kirschner, P. A., & Van Merriënboer, J. J. G. (2012). What makes a good musical improviser? An expert view on improvisational expertise. In E. King & E. Himonides (Eds.), Abstracts: SEMPRE 40th anniversary conference (p. 166). London, UK: International Music Education Research

  19. The Effects of Improvisational Music Therapy on Joint Attention Behaviours in Children with Autistic Spectrum Disorder

    DEFF Research Database (Denmark)

    Kim, Jinah

    2006-01-01

    into unstructured and structured parts. There were four different types of dependent measurements; the Pervasive Developmental Disorder Behavior Inventory (PDDBI), the Early Social Communication Scales (ESCS), the Mother Play Intervention Profile (MPIP) and DVD analyses of selected session data. 10 children, all......This research investigated the effects of improvisational music therapy on joint attention behaviours in children with autistic spectrum disorder. The study was designed to look at these behaviours in two different conditions, improvisational music therapy and free play, and use both standardized...... male, age between 3-6 year old, with clear diagnoses of autistic spectrum disorder completed the trial. The overall results from the PDDBI, the ESCS and session analysis were generally in favour of music therapy over free play, indicating improvisational music therapy was more effective at improving...

  20. Development of a Rubric for Collegiate Jazz Improvisation Performance Assessment

    Science.gov (United States)

    Moore, Kendall Ryan

    2016-01-01

    The purpose of this study was to develop a jazz improvisation rubric for the evaluation of collegiate jazz improvisation. To create this measure, research objectives were devised to investigate the aurally-observed performer-controlled components of improvisation, which aurally-observed components should be evaluated in an improvisatory…

  1. Tactile Paths : on and through Notation for Improvisers

    NARCIS (Netherlands)

    Williams, C.A.

    2016-01-01

    Tactile Paths: on and through Notation for Improvisers is an artistic research project that articulates and expands the nexus of notation and improvisation in contemporary and experimental music. The project interweaves direct artistic experience with insights from improvisation studies, the social

  2. Developing Musical Creativity through Improvisation in the Large Performance Classroom

    Science.gov (United States)

    Norgaard, Martin

    2017-01-01

    Improvisation is an ideal way to develop musical creativity in ensemble settings. This article describes two prominent theoretical frameworks related to improvisation. Next, based on research with developing and expert improvisers, it discusses how to sequence improvisatory activities so that students feel accomplished at every step. Finally, the…

  3. Symbolic Interactionism in Music Education: Eight Strategies for Collaborative Improvisation

    Science.gov (United States)

    Monk, Augusto

    2013-01-01

    Learning improvisation in music is often treated as the process of gaining skills to spontaneously perform within the conventions of a style. Alternatively, learning improvisation can offer musicians a place to explore sound as it happens in free improvisation. Within the school setting, the former approach is commonly used in the jazz programs,…

  4. Tactile paths : on and through notation for improvisers

    NARCIS (Netherlands)

    Williams, C.A.

    2016-01-01

    Tactile Paths: on and through Notation for Improvisers is an artistic research project that articulates and expands the nexus of notation and improvisation in contemporary and experimental music. The project interweaves direct artistic experience with insights from improvisation studies, the social

  5. Using Baroque Techniques to Teach Improvisation in Your Classroom

    Science.gov (United States)

    Yoo, Hyesoo

    2015-01-01

    Before our current notation system was widely adopted by musicians, improvisation was a key component of music throughout the Western world. One of the fundamental elements of the baroque style, namely, using improvised embellishment, offered musicians great artist liberty. During the baroque period, improvisation spread across Europe and beyond.…

  6. Development of a Rubric for Collegiate Jazz Improvisation Performance Assessment

    Science.gov (United States)

    Moore, Kendall Ryan

    2016-01-01

    The purpose of this study was to develop a jazz improvisation rubric for the evaluation of collegiate jazz improvisation. To create this measure, research objectives were devised to investigate the aurally-observed performer-controlled components of improvisation, which aurally-observed components should be evaluated in an improvisatory…

  7. Improvisation during Process-Technology Adoption

    DEFF Research Database (Denmark)

    Tjørnehøj, Gitte; Mathiassen, Lars

    2010-01-01

    Most software firms struggle to take advantage of the potential benefits of software process improvement (SPI) as they adopt this technology into the complex and dynamic realities of their day-to-day operation. Such efforts are therefore typically fluctuating between management's attempt to control...... SPI technology adoption and events that causes the process to drift in unpredictable directions. To further understand how management's attempt to control the process is complemented by drifting, this article investigates the role of improvisation in adoption of SPI technology in a Danish software...... firm, SmallSoft, over a 10-year period (1996-2005). We found that micro-level and macro-level improvisations interacted, often in uncoordinated ways, to shape SPI technology adoption at SmallSoft. The improvisations enhanced employee creativity, motivation and empowerment, created momentum...

  8. The Five Improvisation "Brains": A Pedagogical Model for Jazz Improvisation at High School and the Undergraduate Level

    Science.gov (United States)

    Monk, Augusto

    2012-01-01

    The learning of jazz improvisation is often treated as the incorporation of stylistic vocabulary and development of technical dexterity. Although this methodology is effective, considering other aspects of jazz improvisation can make the learning process a more holistic and less technical endeavour. My experience teaching improvisation has led me…

  9. The Five Improvisation "Brains": A Pedagogical Model for Jazz Improvisation at High School and the Undergraduate Level

    Science.gov (United States)

    Monk, Augusto

    2012-01-01

    The learning of jazz improvisation is often treated as the incorporation of stylistic vocabulary and development of technical dexterity. Although this methodology is effective, considering other aspects of jazz improvisation can make the learning process a more holistic and less technical endeavour. My experience teaching improvisation has led me…

  10. Impaired Maintenance of Interpersonal Synchronization in Musical Improvisations of Patients with Borderline Personality Disorder

    Directory of Open Access Journals (Sweden)

    Katrien Foubert

    2017-04-01

    Full Text Available Borderline personality disorder (BPD is a serious and complex mental disorder with a lifetime prevalence of 5.9%, characterized by pervasive difficulties with emotion regulation, impulse control, and instability in interpersonal relationships and self-image. Impairments in interpersonal functioning have always been a prominent characteristic of BPD, indicating a need for research to identify the specific interpersonal processes that are problematic for diagnosed individuals. Previous research has concentrated on self-report questionnaires, unidirectional tests, and experimental paradigms wherein the exchange of social signals between individuals was not the focus. We propose joint musical improvisation as an alternative method to investigate interpersonal processes. Using a novel, carefully planned, ABA′ accompaniment paradigm, and taking into account the possible influences of mood, psychotropic medication, general attachment, and musical sophistication, we recorded piano improvisations of 16 BPD patients and 12 matched healthy controls. We hypothesized that the insecure attachment system associated with BPD would be activated in the joint improvisation and manifest in measures of timing behavior. Results indicated that a logistic regression model, built on differences in timing deviations, predicted diagnosis with 82% success. More specifically, over the course of the improvisation B section (freer improvisation, controls' timing deviations decreased (temporal synchrony became more precise whereas that of the patients with BPD did not, confirming our hypothesis. These findings are in accordance with previous research, where BPD is characterized by difficulties in attachment relationships such as maintaining strong attachment with others, but it is novel to find empirical evidence of such issues in joint musical improvisation. We suggest further longitudinal research within the field of music therapy, to study how recovery of these timing

  11. Impaired Maintenance of Interpersonal Synchronization in Musical Improvisations of Patients with Borderline Personality Disorder

    Science.gov (United States)

    Foubert, Katrien; Collins, Tom; De Backer, Jos

    2017-01-01

    Borderline personality disorder (BPD) is a serious and complex mental disorder with a lifetime prevalence of 5.9%, characterized by pervasive difficulties with emotion regulation, impulse control, and instability in interpersonal relationships and self-image. Impairments in interpersonal functioning have always been a prominent characteristic of BPD, indicating a need for research to identify the specific interpersonal processes that are problematic for diagnosed individuals. Previous research has concentrated on self-report questionnaires, unidirectional tests, and experimental paradigms wherein the exchange of social signals between individuals was not the focus. We propose joint musical improvisation as an alternative method to investigate interpersonal processes. Using a novel, carefully planned, ABA′ accompaniment paradigm, and taking into account the possible influences of mood, psychotropic medication, general attachment, and musical sophistication, we recorded piano improvisations of 16 BPD patients and 12 matched healthy controls. We hypothesized that the insecure attachment system associated with BPD would be activated in the joint improvisation and manifest in measures of timing behavior. Results indicated that a logistic regression model, built on differences in timing deviations, predicted diagnosis with 82% success. More specifically, over the course of the improvisation B section (freer improvisation), controls' timing deviations decreased (temporal synchrony became more precise) whereas that of the patients with BPD did not, confirming our hypothesis. These findings are in accordance with previous research, where BPD is characterized by difficulties in attachment relationships such as maintaining strong attachment with others, but it is novel to find empirical evidence of such issues in joint musical improvisation. We suggest further longitudinal research within the field of music therapy, to study how recovery of these timing habits are related

  12. Exit from Synchrony in Joint Improvised Motion

    Science.gov (United States)

    Dahan, Assi; Noy, Lior; Hart, Yuval; Mayo, Avi; Alon, Uri

    2016-01-01

    Motion synchrony correlates with effective and well-rated human interaction. However, people do not remain locked in synchrony; Instead, they repeatedly enter and exit synchrony. In many important interactions, such as therapy, marriage and parent-infant communication, it is the ability to exit and then re-enter synchrony that is thought to build strong relationship. The phenomenon of entry into zero-phase synchrony is well-studied experimentally and in terms of mathematical modeling. In contrast, exit-from-synchrony is under-studied. Here, we focus on human motion coordination, and examine the exit-from-synchrony phenomenon using experimental data from the mirror game paradigm, in which people perform joint improvised motion, and from human tracking of computer-generated stimuli. We present a mathematical mechanism that captures aspects of exit-from-synchrony in human motion. The mechanism adds a random motion component when the accumulated velocity error between the players is small. We introduce this mechanism to several models for human coordinated motion, including the widely studied HKB model, and the predictor-corrector model of Noy, Dekel and Alon. In all models, the new mechanism produces realistic simulated behavior when compared to experimental data from the mirror game and from tracking of computer generated stimuli, including repeated entry and exit from zero-phase synchrony that generates a complexity of motion similar to that of human players. We hope that these results can inform future research on exit-from-synchrony, to better understand the dynamics of coordinated action of people and to enhance human-computer and human-robot interaction. PMID:27711185

  13. The model of counterpoint improvisation and the methods of improvisation in popular music

    Directory of Open Access Journals (Sweden)

    Adam Fulara

    2013-06-01

    Full Text Available The article consists of two parts. The first, more general, contains a description of the phenomena associated with improvisation, especially guitar, detailing the execution issues facing the improviser. Two points of view are presented: the first, more detailed, describes the elements of music and its importance in the process of improvisation, the second - more general - speaks of phenomena which cannot be described or analyzed in a simple way, or that are different for each track. These include the interaction between team members, expressing emotions through music and research problem of searching for one's own voice in art. Moreover, this section contains a description of three very different approaches to guitar improvisation. The first is the use of a tonal center (enriched with dominant tensions; the second method (used in fusion music is to combine the harmony of the composition with relevant scales; the third (typical for bebop music is based on the strict use of improvised chord sounds without the use of scales. The second section of the text provides a description of a specific type of polyphonic improvisation with the use of two-handed tapping on the guitar. This model stands in contrast to the three previously described ways of understanding guitar improvisation. The system is based on methods used in both the Renaissance and Baroque polyphony (among others in the leading Cantus Firmus melody or the counterpoint rules as well as on assumptions of one voice bebop improvisation (the use of leading sound solutions specific to natural foursounds. This description refers back to the first part of the article, grouping issues around the individual elements of a musical work. This section contains notes and observations collected during the eight years the author spent searching for his own musical way.

  14. Organized Improvisation: 20 Years of Organizing.

    Science.gov (United States)

    Weick, Karl E.

    1989-01-01

    Uses 20 years of research on organizing as a way of viewing current research efforts and of laying a foundation for future efforts. Compares organizational adjustments to jazz improvisations. Argues that, because of the relationship between organizational quality and criticism, there is no need for the additional trappings of hierarchy, rules,…

  15. Novice Collaboration in Solo and Accompaniment Improvisation

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen

    2012-01-01

    This study investigates how non-musicians engaged in a solo-accompaniment music improvisation relationship. Seven user teams interacted with two electronic music instruments integrated in two pen tablets. One instrument was a melody instrument and the other a chord instru-ment. The study was done...

  16. Abnormal magnetization behaviors in Sm–Ni–Fe–Cu alloys

    Energy Technology Data Exchange (ETDEWEB)

    Yang, W.Y.; Zhang, Y.F.; Zhao, H.; Chen, G.F.; Zhang, Y.; Du, H.L.; Liu, S.Q.; Wang, C.S.; Han, J.Z.; Yang, Y.C. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Yang, J.B. [State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2016-06-01

    The magnetization behaviors in Sm–Ni–Fe–Cu alloys at low temperatures have been investigated. It was found that the hysteresis loops show wasp-waisted character at low temperatures, which has been proved to be related to the existence of multi-phases, the Fe/Ni soft magnetic phases and the CaCu{sub 5}-type hard magnetic phase. A smooth-jump behavior of the magnetization is observed at T>5 K, whereas a step-like magnetization process appears at T<5 K. The CaCu{sub 5}-type phase is responsible for such abnormal magnetization behavior. The magnetic moment reversal model with thermal activation is used to explain the relation of the critical magnetic field (H{sub cm}) to the temperature (T>5 K). The reversal of the moment direction has to cross over an energy barrier of about 6.6×10{sup −15} erg. The step-like jumps of the magnetization below 5 K is proposed to be resulted from a sharp increase of the sample temperature under the heat released by the irreversible domain wall motion. - Highlights: • Two different magnetization mechanisms, controlled by temperature, have been found in the Sm–Ni–Fe–Cu alloys. The smooth-jump behavior of the magnetization is observed at T>5 K and the step-like magnetization process appears at T<5 K. • The magnetic moment reversal model with thermal activation has been successfully used to explain the relation of the critical magnetic field (H{sub cm}) to the temperature (T>5 K). The energy barrier for the reversal of the moment direction has been found to be about 6.6×10{sup −15} erg. • The transition field for the step-like jumps is very strict, independent from the magnetic sweep rate. This is remarkably different from the similar step-like jump behavior in reference [20]. • According to the SEM images and EDX analysis, two kinds of regions are found in the alloys. The Fe–Ni–Cu regions are surrounded by the 1:5 Sm–Ni–Fe–Cu regions and shows fish-bone like structure. An interesting thing is that the Fe

  17. Random magnetic anisotropy: Switching and coercivity behavior

    Science.gov (United States)

    Creswell, A.; Paul, D. I.

    1990-05-01

    Starting from a Hamiltonian based on the random magnetic anisotropy model to describe the magnetic characteristics of amorphous materials such as TbFe2, we determine the low-temperature dependence of the coercivity as well as the magnetization dynamics of these materials. Our model features clusters, each characterized by its anisotropy direction. The exchange energy term entering the Hamiltonian is represented by an effective exchange interaction acting in the intercluster regions. Our Hamiltonian has a minimum in each of the two opposite hemispheres defined by the applied field. We derive the temperature-dependent coercivity by calculating the field necessary to have the one metastable minimum disappear. Our results agree well with experimental data for reasonable values of the parameters. We study the dynamics of the magnetization at 0 K by performing a numerical integration of the equations of motion derived from our Hamiltonian augmented by a Gilbert and Kelly damping term. The average magnetization of the material is reevaluated at each integration step in order for the mean-field approximation for exchange to remain physically meaningful. We obtain the time dependence of the magnetization, determine the switching fields and switching times, and study the influence of the exchange on the results.

  18. Magnetic behavior of nanocrystalline ErCo(2).

    Science.gov (United States)

    Das, Sitikantha D; Mohapatra, Niharika; Iyer, Kartik K; Bapat, R D; Sampathkumaran, E V

    2009-07-22

    We have investigated the magnetic behavior of the nanocrystalline form of a well-known Laves phase compound, ErCo(2)-the bulk form of which has been known to undergo an interesting first-order ferrimagnetic ordering near 32 K-synthesized by high-energy ball-milling. It is found that, in these nanocrystallites, Co exhibits ferromagnetic order at room temperature, as inferred from the magnetization data. However, the magnetic transition temperature for the Er sub-lattice remains essentially unaffected suggesting the (Er)4f-Co(3d) coupling is weak on Er magnetism. The net magnetic moment as measured at high fields, for example at 120 kOe, is significantly reduced with respect to that for the bulk in the ferrimagnetically ordered state and possible reasons are outlined for this. We have also compared the magnetocaloric behavior for the bulk and for nanoparticles.

  19. Activation and connectivity patterns of the presupplementary and dorsal premotor areas during free improvisation of melodies and rhythms.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-10-15

    Free, i.e. non-externally cued generation of movement sequences is fundamental to human behavior. We have earlier hypothesized that the dorsal premotor cortex (PMD), which has been consistently implicated in cognitive aspects of planning and selection of spatial motor sequences may be particularly important for the free generation of spatial movement sequences, whereas the pre-supplementary motor area (pre-SMA), which shows increased activation during perception, learning and reproduction of temporal sequences, may contribute more to the generation of temporal structures. Here we test this hypothesis using fMRI and musical improvisation in professional pianists as a model behavior. We employed a 2 × 2 factorial design with the factors Melody (Specified/Improvised) and Rhythm (Specified/Improvised). The main effect analyses partly confirmed our hypothesis: there was a main effect of Melody in the PMD; the pre-SMA was present in the main effect of Rhythm, as predicted, as well as in the main effect of Melody. A psychophysiological interaction analysis of functional connectivity demonstrated that the correlation in activity between the pre-SMA and cerebellum was higher during rhythmic improvisation than during the other conditions. In summary, there were only subtle differences in activity level between the pre-SMA and PMD during improvisation, regardless of condition. Consequently, the free generation of rhythmic and melodic structures, appears to be largely integrated processes but the functional connectivity between premotor areas and other regions may change during free generation in response to sequence-specific spatiotemporal demands.

  20. Analysis of thermal demagnetization behavior of Nd–Fe–B sintered magnets using magnetic domain observation

    Directory of Open Access Journals (Sweden)

    Masaaki Takezawa

    2016-05-01

    Full Text Available We used magnetic domain observation to statistically observe the thermal demagnetization behavior of Nd–Fe–B sintered magnets at elevated temperatures up to 150 °C. Simultaneous magnetization reversal in a hundred adjacent grains occurred at 90 °C because of the magnetic interaction among the grains beyond grain boundaries in the Dysprosium (Dy-free low-coercivity magnet. Conversely, simultaneous magnetization reversal in a hundred grains did not occur in the Dy-added high-coercivity magnets, and the demagnetizing ratio steadily increased with temperature. Furthermore, the addition of Dy induced high thermal stability by eliminating the simultaneous thermal demagnetization, which was caused by the magnetic interaction among the grains.

  1. Neural substrates of spontaneous musical performance: an FMRI study of jazz improvisation.

    Science.gov (United States)

    Limb, Charles J; Braun, Allen R

    2008-02-27

    To investigate the neural substrates that underlie spontaneous musical performance, we examined improvisation in professional jazz pianists using functional MRI. By employing two paradigms that differed widely in musical complexity, we found that improvisation (compared to production of over-learned musical sequences) was consistently characterized by a dissociated pattern of activity in the prefrontal cortex: extensive deactivation of dorsolateral prefrontal and lateral orbital regions with focal activation of the medial prefrontal (frontal polar) cortex. Such a pattern may reflect a combination of psychological processes required for spontaneous improvisation, in which internally motivated, stimulus-independent behaviors unfold in the absence of central processes that typically mediate self-monitoring and conscious volitional control of ongoing performance. Changes in prefrontal activity during improvisation were accompanied by widespread activation of neocortical sensorimotor areas (that mediate the organization and execution of musical performance) as well as deactivation of limbic structures (that regulate motivation and emotional tone). This distributed neural pattern may provide a cognitive context that enables the emergence of spontaneous creative activity.

  2. Collective Talent : A Study of Improvisational Group Performance in Music

    OpenAIRE

    Jong, de, F.

    2006-01-01

    Improvised music performance offers remarkable and dramatic examples of the talented ways in which group members can interact and inspire each other. Such musical sessions can serve as examples of improvised performance of groups in general. This thesis reports on ways of initiating and supporting talented group improvisation. It addresses the question which interface is needed to generate collectives with collective talent. Inspired by Pask's Conversation Theory, the author has developed a t...

  3. Creativity and improvisation as therapeutic tools within music therapy.

    Science.gov (United States)

    Tomaino, Concetta M

    2013-11-01

    The neuroscience of creativity and music improvisation is a fascinating topic and one with strong implications for clinical music therapy. Music therapists are trained to use musical improvisation as a means to bring their clients into deeper therapeutic relationship as well as free up any inhibitions or limitations that may block recovery. Could recent fMRI studies of jazz musicians showing areas of brain activation during music improvisation provide a new framework to understand underlying mechanisms at work with neurologically impaired individuals?

  4. Improvisation during Process-Technology Adoption

    DEFF Research Database (Denmark)

    Tjørnehøj, Gitte; Mathiassen, Lars

    2010-01-01

    SPI technology adoption and events that causes the process to drift in unpredictable directions. To further understand how management's attempt to control the process is complemented by drifting, this article investigates the role of improvisation in adoption of SPI technology in a Danish software......Most software firms struggle to take advantage of the potential benefits of software process improvement (SPI) as they adopt this technology into the complex and dynamic realities of their day-to-day operation. Such efforts are therefore typically fluctuating between management's attempt to control...... in the adoption process despite constrained resources, and, most importantly, helped adapt SPI technology to the everyday practices at SmallSoft. However, we also identified un-called for improvisations and outcomes that were uncoordinated with SmallSoft's goals. Based on these findings we discuss how management...

  5. Detecting underwater improvised explosive threats (DUIET)

    Science.gov (United States)

    Feeley, Terry

    2010-04-01

    Improvised Explosive Devices (IEDs) have presented a major threat in the wars in Afghanistan and Iraq. These devices are powerful homemade land mines that can be small and easily hidden near roadsides. They are then remotely detonated when Coalition Forces pass by either singly or in convoys. Their rapid detection, classification and destruction is key to the safety of troops in the area. These land based bombs will have an analogue in the underwater theater especially in ports, lakes, rivers and streams. These devices may be used against Americans on American soil as an element of the global war on terrorism (GWOT) Rapid detection and classification of underwater improvised explosive devices (UIED) is critical to protecting innocent lives and maintaining the day to day flow of commerce. This paper will discuss a strategy and tool set to deal with this potential threat.

  6. Improvising Linguistic Style Social and Affective Bases for Agent Personality

    CERN Document Server

    Walker, M A; Whittaker, S J; Walker, Marilyn A.; Cahn, Janet E.; Whittaker, Stephen J.

    1997-01-01

    This paper introduces Linguistic Style Improvisation, a theory and set of algorithms for improvisation of spoken utterances by artificial agents, with applications to interactive story and dialogue systems. We argue that linguistic style is a key aspect of character, and show how speech act representations common in AI can provide abstract representations from which computer characters can improvise. We show that the mechanisms proposed introduce the possibility of socially oriented agents, meet the requirements that lifelike characters be believable, and satisfy particular criteria for improvisation proposed by Hayes-Roth.

  7. Control Improvisation with Application to Music

    Science.gov (United States)

    2013-11-04

    Control Improvisation with Application to Music Alexandre Donze Sophie Libkind Sanjit A. Seshia David Wessel Electrical Engineering and Computer...to Music 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...domain of music . More speci cally, we consider the scenario of generating a monophonic Jazz melody (solo) on a given song harmonization. The music is

  8. Improvised microinjection technique for mosquito vectors

    OpenAIRE

    Sampath, Kumar S.; H.P.Puttaraju

    2012-01-01

    Background & objectives: Bio-manipulation technique is of primary importance during the development of transgenic mosquitoes. The study describes the variable factors that influence the viability of medically important mosquito vectors during microinjection. Methods: Three mosquito vectors belonging to the genus Aedes, Anopheles and Culex were microinjected at different developmental stages of their life cycle viz., egg, larvae, pupae and adult. Results: The improvisations revealed an increas...

  9. [Beyond suffering, schizophrenic improvisation and therapeutic challenges].

    Science.gov (United States)

    Bizot, Tatiana

    2016-01-01

    Led jointly by an actress and an occupational therapist, an 'improvisation' activity has been set up within the Sainte-Anne University Hospital SHU Sector 14 for hospitalised patients, on medical prescription. This containing environment provides psychological support and encourages patients with schizophrenia to explore their creativity and to 'let go' so as to discover new physical possibilities. The group thereby becomes a support for the relationship and the development of verbal and non-verbal communication.

  10. Connecting to create: expertise in musical improvisation is associated with increased functional connectivity between premotor and prefrontal areas.

    Science.gov (United States)

    Pinho, Ana Luísa; de Manzano, Örjan; Fransson, Peter; Eriksson, Helene; Ullén, Fredrik

    2014-04-30

    Musicians have been used extensively to study neural correlates of long-term practice, but no studies have investigated the specific effects of training musical creativity. Here, we used human functional MRI to measure brain activity during improvisation in a sample of 39 professional pianists with varying backgrounds in classical and jazz piano playing. We found total hours of improvisation experience to be negatively associated with activity in frontoparietal executive cortical areas. In contrast, improvisation training was positively associated with functional connectivity of the bilateral dorsolateral prefrontal cortices, dorsal premotor cortices, and presupplementary areas. The effects were significant when controlling for hours of classical piano practice and age. These results indicate that even neural mechanisms involved in creative behaviors, which require a flexible online generation of novel and meaningful output, can be automated by training. Second, improvisational musical training can influence functional brain properties at a network level. We show that the greater functional connectivity seen in experienced improvisers may reflect a more efficient exchange of information within associative networks of importance for musical creativity.

  11. Magnetic Field Effect on Critical Behavior of Perovskite Ferromagnet

    Institute of Scientific and Technical Information of China (English)

    Tian Hongwei; Zheng Weitao; Chen Yanping; Ding Tao; Wang Xin; Kan Dongwu

    2005-01-01

    The polycrystalline samples of La2/3Ca1/3MnO3 were prepared by a conventional solid state reaction method. The magnetizations (ZFC, FC and initial magnetization) of the polycrystalline La2/3Ca1/3MnO3 were measured with superconducting quantum interference device magnetometer. The scaling theory was employed to study the changes of critical behavior arising from the applied external field. The critical parameter β decreases with increasing the external magnetic field results in an increase in the magnitude of ferromagnetic ordering.

  12. Squeeze behaviors of magnetic powders between two parallel plates

    Science.gov (United States)

    Chen, Kaikai; Tian, Yu; Shan, Lei; Zhang, Xiangjun; Meng, Yonggang

    2014-10-01

    The dynamic compressive and static normal stresses of magnetic powders (MPs) with the constant volume squeezed between two parallel plates were experimentally studied. The compressive stress increased in a power law as the gap distance decreased, with an exponent range of -0.73 (0.04 T) to -2.63 (0.77 T). The values of the scale factor to normalize the compressive curves were mainly dominated by the applied magnetic field. The compressive behavior of the MPs showed a less significant velocity effect and initial gap distance effect than those of the magnetorheological (MR) and electrorheological (ER) fluids because of the absence of a host liquid. The compressive stress was generated by the serious particle aggregation, which was induced by a magnetic field and friction during compression. This study is designed to further the understanding of the behavior of smart ER/MR materials and the application of MP actuators in squeeze mode.

  13. Macroscopic behavior and microscopic magnetic properties of nanocarbon

    Energy Technology Data Exchange (ETDEWEB)

    Lähderanta, E., E-mail: Erkki.Lahderanta@lut.fi [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); Ryzhov, V.A. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); Petersburg Nuclear Physics Institute, NRC “Kurchatov Institute”, Orlova Coppice, Gatchina, Leningrad province 188300 (Russian Federation); Lashkul, A.V. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); Galimov, D.M. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); South Ural State University, 454080 Chelyabinsk (Russian Federation); Titkov, A.N. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); A. F. Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation); Matveev, V.V. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); Saint-Petersburg State University, Saint-Petersburg 198504 (Russian Federation); Mokeev, M.V. [Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg (Russian Federation); Kurbakov, A.I. [Petersburg Nuclear Physics Institute, NRC “Kurchatov Institute”, Orlova Coppice, Gatchina, Leningrad province 188300 (Russian Federation); Lisunov, K.G. [Lappeenranta University of Technology, PO Box 20, FIN-53851 Lappeenranta (Finland); Institute of Applied Physics ASM, Academiei Str., 5, MD 2028 Kishinev (Moldova, Republic of)

    2015-06-01

    Here are presented investigations of powder and glass-like samples containing carbon nanoparticles, not intentionally doped and doped with Ag, Au and Co. The neutron diffraction study reveals an amorphous structure of the samples doped with Au and Co, as well as the magnetic scattering due to a long-range FM order in the Co-doped sample. The composition and molecular structure of the sample doped with Au is clarified with the NMR investigations. The temperature dependence of the magnetization, M (T), exhibits large irreversibility in low fields of B=1–7 mT. M (B) saturates already above 2 T at high temperatures, but deviates from the saturation behavior below ~50 (150 K). Magnetic hysteresis is observed already at 300 K and exhibits a power-law temperature decay of the coercive field, B{sub c} (T). The macroscopic behavior above is typical of an assembly of partially blocked magnetic nanoparticles. The values of the saturation magnetization, M{sub s}, and the blocking temperature, T{sub b}, are obtained as well. However, the hysteresis loop in the Co-doped sample differs from that in other samples, and the values of B{sub c} and M{sub s} are noticeably increased. - Highlights: • We have investigated powder and glassy samples with carbon nanoparticles. • They include an undoped sample and those doped with Ag, Au and Co. • Neutron diffraction study reveals amorphous structure of Au- and Co-doped samples. • Composition and molecular structure of Au-doped sample was investigated with NMR. • Magnetic behavior is typical of an assembly of partially blocked magnetic nanoparticles.

  14. Risk-Taking and Large-Group Dance (Improvisation)

    NARCIS (Netherlands)

    Cerqueira da Silva Jr., João

    2016-01-01

    Improvisation in dance is often conceived of as a practice that involves a kind of risk-taking that is occasioned by spontaneity and a ‘stepping into the unknown’. Choreography, usually considered to be the ‘other’ of improvisation, on the contrary, is associated with ‘knowing’ and repetition, and a

  15. Collective Talent : A Study of Improvisational Group Performance in Music

    NARCIS (Netherlands)

    Jong, de Jacqueline B.

    2006-01-01

    Improvised music performance offers remarkable and dramatic examples of the talented ways in which group members can interact and inspire each other. Such musical sessions can serve as examples of improvised performance of groups in general. This thesis reports on ways of initiating and supporting t

  16. Use Jazz to Teach Your String Students Improvisation

    Science.gov (United States)

    Caputo, Charles R.

    2006-01-01

    Standards 3 and 9 of the National Standards for Music Education charge teachers to teach improvisation as well as music of diverse cultures. Jazz is a musical style that is perfect to cover both content areas. Until now, however, jazz repertoire and improvisation have not played a major role in the education of string students. One reason is that…

  17. Relationships among Selected Practice Behaviours and Achievement in Jazz Improvisation

    Science.gov (United States)

    Watson, Kevin E.

    2015-01-01

    The purpose of this exploratory study was to examine the practice strategies that collegiate music majors chose to employ in preparing for a jazz improvisation performance, and the relationships among selected practice behaviours and achievement in instrumental jazz improvisation. Participants for the study (N = 62) were enrolled as music majors…

  18. Using Comedy Improvisation Techniques to Support Dance Training

    Science.gov (United States)

    Larimer, Amy

    2012-01-01

    Although contemporary dance improvisation techniques and comedy improvisation are seldom linked, the two forms evolved around the same time and have many similarities. Both forms exist in the moment, share a highly ephemeral nature, and make use of physical games and structures. Both forms teach students the skill of being present, so essential to…

  19. Use Jazz to Teach Your String Students Improvisation

    Science.gov (United States)

    Caputo, Charles R.

    2006-01-01

    Standards 3 and 9 of the National Standards for Music Education charge teachers to teach improvisation as well as music of diverse cultures. Jazz is a musical style that is perfect to cover both content areas. Until now, however, jazz repertoire and improvisation have not played a major role in the education of string students. One reason is that…

  20. Using Comedy Improvisation Techniques to Support Dance Training

    Science.gov (United States)

    Larimer, Amy

    2012-01-01

    Although contemporary dance improvisation techniques and comedy improvisation are seldom linked, the two forms evolved around the same time and have many similarities. Both forms exist in the moment, share a highly ephemeral nature, and make use of physical games and structures. Both forms teach students the skill of being present, so essential to…

  1. Collective Talent : A Study of Improvisational Group Performance in Music

    NARCIS (Netherlands)

    Jong, de Jacqueline B.

    2006-01-01

    Improvised music performance offers remarkable and dramatic examples of the talented ways in which group members can interact and inspire each other. Such musical sessions can serve as examples of improvised performance of groups in general. This thesis reports on ways of initiating and supporting

  2. Young Pianists Exploring Improvisation Using Interactive Music Technology

    Science.gov (United States)

    Rowe, Victoria; Triantafyllaki, Angeliki; Anagnostopoulou, Xristina

    2015-01-01

    The use of music technology in the enhancement of young pianists' musical improvisations has been scarcely explored in instrumental music teaching and learning research. In the present study, 19 piano pupils aged 6-10 from the UK and Greece used an interactive improvisation system called Musical Interaction Relying On Reflexion (MIROR)-Impro for…

  3. Descriptions of Improvisational Thinking by Artist-Level Jazz Musicians

    Science.gov (United States)

    Norgaard, Martin

    2011-01-01

    Thought processes of seven artist-level jazz musicians, each of whom recorded an improvised solo, were investigated. Immediately after completing their improvisations, participants listened to recordings of their playing and looked at the notation of their solos as they described in a directed interview the thinking processes that led to the…

  4. Collective Talent : A Study of Improvisational Group Performance in Music

    NARCIS (Netherlands)

    Jong, de Jacqueline B.

    2006-01-01

    Improvised music performance offers remarkable and dramatic examples of the talented ways in which group members can interact and inspire each other. Such musical sessions can serve as examples of improvised performance of groups in general. This thesis reports on ways of initiating and supporting t

  5. Free Improvisation and Performance Anxiety among Piano Students

    Science.gov (United States)

    Allen, Robert

    2013-01-01

    The purpose of this study was to compare the levels of anxiety that students experienced according to whether their public performance consisted of a free improvisation or a repertory piece. The researcher had two objectives: (1) examine the relationship of students' levels of anxiety to free improvisation and repertory pieces during a…

  6. Pedagogical Techniques of Improvisation Instructors without Academic Credentials

    Science.gov (United States)

    Salonen, Richard Wayne

    2010-01-01

    The importance of music improvisation can be seen in its inclusion in the National Standards for Music Education and the accreditation standards for the National Association of Schools of Music. The purpose of this study was to examine the pedagogical techniques and materials of improvisation instructors who do not hold academic credentials. The…

  7. Dramaturgical and Music-Theoretical Approaches to Improvisation Pedagogy

    Science.gov (United States)

    Huovinen, Erkki; Tenkanen, Atte; Kuusinen, Vesa-Pekka

    2011-01-01

    The aim of this article is to assess the relative merits of two approaches to teaching musical improvisation: a music-theoretical approach, focusing on chords and scales, and a "dramaturgical" one, emphasizing questions of balance, variation and tension. Adult students of music pedagogy, with limited previous experience in improvisation,…

  8. Relationships among Selected Practice Behaviours and Achievement in Jazz Improvisation

    Science.gov (United States)

    Watson, Kevin E.

    2015-01-01

    The purpose of this exploratory study was to examine the practice strategies that collegiate music majors chose to employ in preparing for a jazz improvisation performance, and the relationships among selected practice behaviours and achievement in instrumental jazz improvisation. Participants for the study (N = 62) were enrolled as music majors…

  9. Thermal and magnetic behaviors of a melt-textured superconducting bulk magnet in the zero-field-cooling magnetizing process

    Energy Technology Data Exchange (ETDEWEB)

    Oka, T [Faculty of Engineering, Niigata University, 8050 Ikarashi-Nino-cho, Nishi-ku, Niigata 950-2181 (Japan); Yokoyama, K [Ashikaga Department of Electrical and Electronic Engineering, Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558 (Japan); Fujishiro, H; Noto, K [Faculty of Engineering, Iwate University, 3-4-5 Ueda, Morioka, Iwate 020-8551 (Japan)], E-mail: okat@eng.niigata-u.ac.jp

    2009-06-15

    The heat generation and magnetic field trapping behaviors of the melt-textured single-domain Sm-Ba-Cu-O bulk superconductor have been precisely investigated in the zero-field-cooling magnetizing processes (ZFC). The temperature and magnetic flux density were simultaneously measured in the temperature range of 50-60 K. Since the invasion of magnetic flux is suppressed by the superconducting pinning effect, the applied magnetic field is not supplied to the whole of the sample. Therefore, the trapped field distributions consequently exhibit trapezoid shapes. According to the balance of heat generation and draining, the temperature profiles show us distinctive behaviors of magnetic fluxes. Both the temperature and the magnetic flux density kept increasing even after the external magnetic field has stopped growing at 5 T. This is attributed to the flux creeping phenomenon which propagates from the periphery to the center portion of the sample like a snow slide. The highest temperature rise due to the flux motion reached 7.5 K even when the sample was magnetized at a slow sweeping rate of 5.06 mT s{sup -1}. As the temperature profiles were different between the ascending and descending field processes, it is suggested that the magnetic fluxes invade in and diffuse out in different heating manners between the processes. This assists the hypothesis that the time while the moving fluxes heat the sample strongly affects the total amount of heat generation, which acts contrary to the FC case. This behavior implies that the improvements of the heat propagation property of the HTS bulk material by embedding metallic membranes and more powerful/efficient cooling systems must suppress the temperature increases and enhance the field trapping abilities.

  10. The Behavior Of Asymmetric Frontal Couplings With Permanent Magnets In Magnetic Powder And High Temperature Environments

    Directory of Open Access Journals (Sweden)

    Ion DOBROTA

    2002-12-01

    Full Text Available The main purpose of this paper is the comparative analysis of the behavior of frontal couplings with Nd-Fe-B permanent magnets in difficult environments, specific to metallurgy – such as environments with magnetic powders and high temperature – in two constructive variants: symmetric couplings and asymmetric couplings (with divided poles. The results show the superior performance of asymmetric couplings under the given conditions

  11. Play Fluency in Music Improvisation Games for Novices

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie; Andersen, Hans Jørgen; Raudaskoski, Pirkko Liisa

    2011-01-01

    In this paper a collaborative music game for two pen tablets is studied in order to see how two people with no professional music background negotiated musical improvisation. In an initial study of what it is that constitutes play fluency in improvisation, a music game has been designed and evalu......In this paper a collaborative music game for two pen tablets is studied in order to see how two people with no professional music background negotiated musical improvisation. In an initial study of what it is that constitutes play fluency in improvisation, a music game has been designed...... suggestions for how o direct future designs of collaborative music improvisation games towards ways of mutual play....

  12. Exchange spring like magnetic behavior in cobalt ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Chithra, M.; Anumol, C.N. [Department of Physics, Central University of Kerala, Riverside Transit Campus, Nileshwar, P.O. Padnekkad, Kasaragod, Kerala 671314 (India); Sahu, Baidyanath [Department of Physics, I.I.T. Bombay, Powai, Mumbai 400076 (India); Sahoo, Subasa C., E-mail: subasa.cs@gmail.com [Department of Physics, Central University of Kerala, Riverside Transit Campus, Nileshwar, P.O. Padnekkad, Kasaragod, Kerala 671314 (India)

    2016-03-01

    Cobalt ferrite nanoparticles were prepared by sol–gel technique and were annealed at 900 °C in air for 2 h. Structural properties were studied by X-ray diffraction, Raman spectroscopy and Fourier transformed infrared spectroscopy. Scanning electron microscopy and transmission electron microscopy studies show presence of mostly two different sizes of grains in these samples. Magnetization value of 58.36 emu/g was observed at 300 K for the as prepared sample and an enhanced magnetization close to the bulk value of 80.59 emu/g was observed for the annealed sample. At 10 K a two stepped hysteresis loop showing exchange spring magnetic behavior was observed accompanied by very high values of coercivity and remanence. Two clear peaks were observed in the derivative of demagnetization curve in the as prepared sample where as two partially overlapped peaks were observed in the annealed sample. The observed magnetic properties can be understood on the basis of the grain size and their distribution leading to the different types of intergranular interactions in these nanoparticles. - Highlights: • Cobalt ferrite nanoparticles were prepared by sol–gel technique and were annealed. • Microscopy studies showed presence of mostly two different sizes of grains. • A two stepped magnetic hysteresis loop was observed in these samples at 10 K. • Two well resolved peaks were observed in the derivative of demagnetization curve. • Grain size and their distribution lead to such two stepped exchange spring behavior.

  13. Magnetic Behavior of Sintered NdFeB Magnets on a Long-Term Timescale

    Directory of Open Access Journals (Sweden)

    Minna Haavisto

    2014-01-01

    Full Text Available Stable polarization of permanent magnets over the lifetime of the application is an important aspect in electrical machine design. Specification of the long-term stability of magnet material is difficult, since knowledge of the phenomenon is incomplete. To be able to optimize magnet material selection, the long-term magnetic behavior of the material must also be understood. This study shows that material with a very square JH curve is stable until a certain critical operating temperature is reached. Major losses are detected as the critical temperature is exceeded. Material with a rounder JH curve does not show a well-defined critical temperature, but increasing losses over a large temperature range. The critical temperature of a material is also dependent on the field conditions. Results differ whether the tests are performed in an open or closed magnetic circuit. In open-circuit tests, the opposing field is not homogeneously distributed throughout the volume of the magnet and thus the long-term behavior is different than that in closed-circuit conditions. Open-circuit tests seem to give bigger losses than closed-circuit tests in cases where the permeance coefficient of the open-circuit sample is considered to be the average permeance coefficient, calculated according to the dimensions of the magnet.

  14. Vocal Improvisation and Creative Thinking by Australian and American University Jazz Singers: A Factor Analytic Study

    Science.gov (United States)

    Ward-Steinman, Patrice Madura

    2008-01-01

    In this study, the author investigated factors underlying vocal improvisation achievement and relationships with the singers' musical background. Participants were 102 college students in Australia and the United States who performed 3 jazz improvisations and 1 free improvisation. Jazz improvisations were rated on rhythmic, tonal, and creative…

  15. Free Improvisation: What It Is, and Why We Should Apply It in Our General Music Classrooms

    Science.gov (United States)

    Niknafs, Nasim

    2013-01-01

    Improvisation, the third content standard for the National Standards for Music Education (Music Educators National Conference, 1994), has received less attention from music teachers. This article advocates for more improvisation specifically free improvisation in general music classrooms. The nature of free improvisation, and its evolution in the…

  16. Vocal Improvisation and Creative Thinking by Australian and American University Jazz Singers: A Factor Analytic Study

    Science.gov (United States)

    Ward-Steinman, Patrice Madura

    2008-01-01

    In this study, the author investigated factors underlying vocal improvisation achievement and relationships with the singers' musical background. Participants were 102 college students in Australia and the United States who performed 3 jazz improvisations and 1 free improvisation. Jazz improvisations were rated on rhythmic, tonal, and creative…

  17. Cyclic behavior of solar inter-network magnetic field

    CERN Document Server

    Jin, Chunlan

    2015-01-01

    Solar inter-network magnetic field is the weakest component of solar magnetism, but contributes most of the solar surface magnetic flux. The study on its origin has been constrained by the inadequate tempo-spatial resolution and sensitivity of polarization observations. With dramatic advances in spatial resolution and detective sensitivity, solar spectro-polarimetry provided by the Solar Optical Telescope aboard Hinode in an interval from solar minimum to maximum of cycle 24 opens an unprecedented opportunity to study the cyclic behavior of solar inter-network magnetic field. More than 1000 Hinode magnetograms observed from 2007 January to 2014 August are selected in the study. It has been found that there is a very slight correlation between sunspot number and magnetic field at the inter-network flux spectrum. From solar minimum to maximum of cycle 24, the flux density of solar inter-network field is invariant, which is 10$\\pm1$ G. The observations suggest that the inter-network magnetic field does not arise...

  18. Effects of high magnetic field on martensitic transformation behavior and structure in Fe-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsuka, H.; Wada, H. [Tsukuba Labs., Ibaraki (Japan). Nat. Res. Inst. for Metals; Ghosh, G. [Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering

    2000-07-01

    Effects of magnetic field on lath-type martensitic transformation behavior and the reverse transformation behavior from lath math martensite to austenite have been investigated in 18Ni maraging steel. It was found that the reverse transformation temperature during heating is increased by magnetic field. Reverse transformation behavior during isothermal holding was also found to be retarded by magnetic field. (orig.)

  19. The Bucket System – A computer mediated signaling system for group improvisation

    DEFF Research Database (Denmark)

    Dahlstedt, Palle; Nilsson, Per Anders; Robair, Gino

    2015-01-01

    The Bucket System is a new system for computer-mediated ensemble improvisation, designed by improvisers for improvisers. Coming from a tradition of structured free ensemble improvisation practices (comprovisation), influenced by post-WW2 experimental music practices, it is a signaling system...... implemented with a set of McMillen QuNeo controllers as input and output interfaces, powered by custom software. It allows for a new kind of on-stage compositional/improvisation interaction....

  20. The Bucket System – A computer mediated signaling system for group improvisation

    DEFF Research Database (Denmark)

    Dahlstedt, Palle; Nilsson, Per Anders; Robair, Gino

    2015-01-01

    The Bucket System is a new system for computer-mediated ensemble improvisation, designed by improvisers for improvisers. Coming from a tradition of structured free ensemble improvisation practices (comprovisation), influenced by post-WW2 experimental music practices, it is a signaling system...... implemented with a set of McMillen QuNeo controllers as input and output interfaces, powered by custom software. It allows for a new kind of on-stage compositional/improvisation interaction....

  1. Jazz improvisers' shared understanding: a case study.

    Science.gov (United States)

    Schober, Michael F; Spiro, Neta

    2014-01-01

    To what extent and in what arenas do collaborating musicians need to understand what they are doing in the same way? Two experienced jazz musicians who had never previously played together played three improvisations on a jazz standard ("It Could Happen to You") on either side of a visual barrier. They were then immediately interviewed separately about the performances, their musical intentions, and their judgments of their partner's musical intentions, both from memory and prompted with the audiorecordings of the performances. Statements from both (audiorecorded) interviews as well as statements from an expert listener were extracted and anonymized. Two months later, the performers listened to the recordings and rated the extent to which they endorsed each statement. Performers endorsed statements they themselves had generated more often than statements by their performing partner and the expert listener; their overall level of agreement with each other was greater than chance but moderate to low, with disagreements about the quality of one of the performances and about who was responsible for it. The quality of the performances combined with the disparities in agreement suggest that, at least in this case study, fully shared understanding of what happened is not essential for successful improvisation. The fact that the performers endorsed an expert listener's statements more than their partner's argues against a simple notion that performers' interpretations are always privileged relative to an outsider's.

  2. Complex magnetic behavior in GdCrO3

    Science.gov (United States)

    Mahana, Sudipta; Manju, U.; Topwal, D.

    2017-05-01

    Magnetic interactions in Gadolinium orthochromites (GdCrO3) are quite complex. It shows strong temperature dependency related to Gd3+-Gd3+, Gd3+-Cr3+ and Cr3+-Cr3+ interactions, resulting in exotic phenomena like spin flipping and spin reorientation. These behaviors are successfully explained by considering Cr 3d-Gd 4f magnetic coupling. The nearest neighbor symmetric and antisymmetric exchange coupling in Cr-sublattice was found to be Je = 11.058 K and D = 2.64 K from modified Curie-Weiss law modeled by Moriya, while positive Zeeman energy between net moments and the applied external magnetic fields was found to drive spin flipping.

  3. Magnetic avalanches in granular ferromagnets: thermal activated collective behavior

    Science.gov (United States)

    Chern, Gia-Wei

    2017-02-01

    We present a numerical study on the thermal activated avalanche dynamics in granular materials composed of ferromagnetic clusters embedded in a non-magnetic matrix. A microscopic dynamical simulation based on the reaction-diffusion process is developed to model the magnetization process of such systems. The large-scale simulations presented here explicitly demonstrate inter-granular collective behavior induced by thermal activation of spin tunneling. In particular, we observe an intriguing criticality controlled by the rate of energy dissipation. We show that thermal activated avalanches can be understood in the framework of continuum percolation and the emergent dissipation induced criticality is in the universality class of 3D percolation transition. Implications of these results to the phase-separated states of colossal magnetoresistance materials and other artificial granular magnetic systems are also discussed.

  4. Static and dynamic critical behavior of thin magnetic Ising films

    Science.gov (United States)

    Sabogal-Suárez, D.; Alzate-Cardona, J. D.; Restrepo-Parra, E.

    2015-09-01

    This work presents a study of the effect of film thickness on the static and dynamic critical behavior of thin magnetic Ising films. Monte Carlo simulations using the Wolff algorithm were performed to determine the static and dynamic critical exponents of the films. A dimensionality crossover from 2D to 3D (due to the finiteness of the films) in the static and dynamic critical behavior was observed as the film thickness increases. In addition, a slight increase in the effective dimension deff and a considerable increase in the critical temperature Tc(∞) were found. Small values for the dynamic critical exponents were obtained, indicating that the Wolff algorithm is a very efficient method for these magnetic systems.

  5. Invariance of the magnetic behavior and AMI in ferromagnetic biphase films with distinct non-magnetic metallic spacers

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.F. [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Gamino, M. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Instituto de Física, Universidade Federal do Rio Grande de Sul, 91501-970 Porto Alegre, RS (Brazil); Andrade, A.M.H. de [Instituto de Física, Universidade Federal do Rio Grande de Sul, 91501-970 Porto Alegre, RS (Brazil); Vázquez, M. [Instituto de Ciencia de Materiales de Madrid, CSIC, 28049 Madrid (Spain); Correa, M.A. [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Bohn, F., E-mail: felipebohn@fisica.ufrn.br [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil)

    2017-02-01

    We investigate the quasi-static magnetic, magnetotransport, and dynamic magnetic properties in ferromagnetic biphase films with distinct non-magnetic metallic spacer layers. We observe that the nature of the non-magnetic metallic spacer material does not have significant influence on the overall biphase magnetic behavior, and, consequently, on the magnetotransport and dynamic magnetic responses. We focus on the magnetoimpedance effect and verify that the films present asymmetric magnetoimpedance effect. Moreover, we explore the possibility of tuning the linear region of the magnetoimpedance curves around zero magnetic field by varying the probe current frequency in order to achieve higher sensitivity values. The invariance of the magnetic behavior and the asymmetric magnetoimpedance effect in ferromagnetic biphase films with distinct non-magnetic metallic spacers place them as promising candidates for probe element and open possibilities to the development of lower-cost high sensitivity linear magnetic field sensor devices.

  6. Invariance of the magnetic behavior and AMI in ferromagnetic biphase films with distinct non-magnetic metallic spacers

    Science.gov (United States)

    Silva, E. F.; Gamino, M.; Andrade, A. M. H. de; Vázquez, M.; Correa, M. A.; Bohn, F.

    2017-02-01

    We investigate the quasi-static magnetic, magnetotransport, and dynamic magnetic properties in ferromagnetic biphase films with distinct non-magnetic metallic spacer layers. We observe that the nature of the non-magnetic metallic spacer material does not have significant influence on the overall biphase magnetic behavior, and, consequently, on the magnetotransport and dynamic magnetic responses. We focus on the magnetoimpedance effect and verify that the films present asymmetric magnetoimpedance effect. Moreover, we explore the possibility of tuning the linear region of the magnetoimpedance curves around zero magnetic field by varying the probe current frequency in order to achieve higher sensitivity values. The invariance of the magnetic behavior and the asymmetric magnetoimpedance effect in ferromagnetic biphase films with distinct non-magnetic metallic spacers place them as promising candidates for probe element and open possibilities to the development of lower-cost high sensitivity linear magnetic field sensor devices.

  7. Corrosion behavior of magnetic ferrite coating prepared by plasma spraying

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yi; Wei, Shicheng, E-mail: wsc33333@163.com; Tong, Hui; Tian, Haoliang; Liu, Ming; Xu, Binshi

    2014-12-15

    Graphical abstract: The saturation magnetization (M{sub s}) of the ferrite coating is 34.417 emu/g while the M{sub s} value of the ferrite powder is 71.916 emu/g. It can be seen that plasma spray process causes deterioration of the room temperature soft magnetic properties. - Highlights: • Spinel ferrite coatings have been prepared by plasma spraying. • The coating consists of nanocrystalline grains. • The saturation magnetization of the ferrite coating is 34.417 emu/g. • Corrosion behavior of the ferrite coating was examined in NaCl solution. - Abstract: In this study, spray dried spinel ferrite powders were deposited on the surface of mild steel substrate through plasma spraying. The structure and morphological studies on the ferrite coatings were carried out using X-ray diffraction, scanning electron microscope and Raman spectroscopy. It was showed that spray dried process was an effective method to prepare thermal spraying powders. The coating showed spinel structure with a second phase of LaFeO{sub 3}. The magnetic property of the ferrite samples were measured by vibrating sample magnetometer. The saturation magnetization (M{sub s}) of the ferrite coating was 34.417 emu/g. The corrosion behavior of coating samples was examined by electrochemical impedance spectroscopy. EIS diagrams showed three corrosion processes as the coating immersed in 3.5 wt.% NaCl solution. The results suggested that plasma spraying was a promising technology for the production of magnetic ferrite coatings.

  8. Unusual magnetic behavior in a chiral-based magnetic memory device

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Dor, Oren; Yochelis, Shira [Department of Applied Physics, Center of Nanoscience and Nanotechnology, Hebrew University, Jerusalem 91904 (Israel); Felner, Israel, E-mail: Israel.felner@mail.huij.ac.il [“Racah” Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Paltiel, Yossi [Department of Applied Physics, Center of Nanoscience and Nanotechnology, Hebrew University, Jerusalem 91904 (Israel)

    2016-01-15

    In recent years chiral molecules were found to act as efficient spin filters. Using a multilayer structure with chiral molecules magnetic memory was realized. Observed rare magnetic phenomena in a chiral-based magnetic memory device was reported by O-Ben Dor et. al in Nature Commun, 4, 2256 (2013). This multi-layered device is built from α-helix L-polyalanine (AHPA-L) adsorbed on gold, Al{sub 2}O{sub 3} (7 nm) and Ni (30 nm) layers. It was shown that certain temperature range the FC branch crosses the magnetic peak (at 55 K) observed in the ZFC curve thus ZFC>FC. We show here that in another similar multi-layered material, at low applied field, the ZFC curve lies above the FC one up to 70 K. The two features have the same origin and the crucial necessary components to exhibit them are: AHPA-L and 30 nm Ni layered thick. Similar effects were also reported in sulfur doped amorphous carbon. A comparison between the two systems and the ingredients for these peculiar observations is discussed. - Highlights: • The highlights of the present manuscript is the peculiar magnetic behavior observed in a multilayer structure with chiral molecules, magnetic memory. • It is shown that certain temperature range the FC branch crosses the magnetic peak (at 55 K) observed in the ZFC curve thus ZFC>FC. • Similar effects were also reported in sulfur doped amorphous carbon.

  9. Serious Gaming for Improvised Explosive Device Neutralization Training

    Directory of Open Access Journals (Sweden)

    Chan Christopher C.K.

    2016-01-01

    Full Text Available An improvised explosive device (IED is a “homemade” bomb intended to cause great harm when it explodes. The public safety task of identifying and neutralizing IEDs falls to military and police services often called explosive disposal units (EDU who act to neutralize the threat associated with the IED either rendering it inoperable or destroying it safely. EDUs train in various aspects of explosive handling and investigation but are limited in the tools available for safely analyzing real world bombs. This paper describes a game based approach to IED training that employs an interactive 3D simulation to spatially identify key IED components of interest. We give an example of how this approach might be used and provide a preliminary evaluation of its potential effectiveness. We employ images formed from a Digital Imaging and Communications in Medicine (DICOM system captured using Magnetic Resonance Imaging (MRI technology to a virtual IED in a game. Empirical evaluation and EDU testimony suggest accurate representation of the IED and the potential efficacy of the proposed approach for successfully identifying components in the bomb for the purposes of EDU training.

  10. Magnetic behavior of manganese bromide hydrates including deuteration effects

    Energy Technology Data Exchange (ETDEWEB)

    DeFotis, G.C., E-mail: gxdefo@wm.edu [Chemistry Department, College of William & Mary, Williamsburg, VA 23187 (United States); Van Dongen, M.J.; Hampton, A.S.; Komatsu, C.H.; Pothen, J.M.; Trowell, K.T.; Havas, K.C.; Chan, D.G.; Reed, Z.D. [Chemistry Department, College of William & Mary, Williamsburg, VA 23187 (United States); Hays, K.; Wagner, M.J. [Chemistry Department, George Washington University, Washington, D.C. 20052 (United States)

    2016-07-15

    The magnetic properties of previously unexamined MnBr{sub 2}·2H{sub 2}O, MnBr{sub 2}·H{sub 2}O, MnBr{sub 2}·2D{sub 2}O and MnBr{sub 2}·D{sub 2}O are studied. Curie–Weiss fits to high temperature data yield θ of −13.1, −3.9, −8.2 and −5.0 K, respectively, in χ{sub M}=C/(T−θ). The net antiferromagnetic exchange yields susceptibility maxima at 6.34, 3.20, 2.10, and 3.40 K, with χ{sub max} of 0.197, 0.357, 0.465 and 0.348 emu/mol, respectively. Noteworthy is the contrast between dideuterate and dihydrate, the largest deuteration effect observed for hydrated transition metal halides. Antiferromagnetic ordering is estimated to occur at 5.91, 2.65, 2.00 and 2.50 K, respectively. The ratio T{sub c}/T{sub max} is 0.93, 0.83, 0.95 and 0.74 in the same order, implying low dimensional magnetism for monohydrate and monodeuterate. Heisenberg model fits to susceptibilities yield primary and secondary exchange interactions. Magnetization data at moderate fields and different temperatures are presented for each substance, and high field data to 70 kG at 2.00 K. Spin-flop transitions are estimated to occur at 45, 33 and 30 kG, respectively, for dihydrate, monohydrate and monodeuterate, but are not observable for MnBr{sub 2}·2D{sub 2}O. The results are analyzed from various perspectives. A different monoclinic unit cell is determined for MnBr{sub 2}·2D{sub 2}O than for MnBr{sub 2}·2H{sub 2}O, with 1.3% larger volume, providing some rationale for the difference in magnetic properties. - Highlights: • The magnetic properties of Mn(II) bromide dihydrate and monohydrate are studied. • The effects of replacing H{sub 2}O by D{sub 2}O are examined for both hydration states. • For monohydrate the change in magnetic behavior on deuteration is small. • For dihydrate the change in magnetic behavior on deuteration is large. • The unit cell of MnBr{sub 2}·2D{sub 2}O is different from and slightly larger than for MnBr{sub 2}·2H{sub 2}O.

  11. Postural coordination during socio-motor improvisation

    Directory of Open Access Journals (Sweden)

    Mathieu Gueugnon

    2016-08-01

    Full Text Available Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation. Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively. Our results revealed the spontaneous emergence of in-phase pattern in ML direction and anti-phase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability and antiphase supporting postural control in AP (mechanical stability. Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

  12. Postural Coordination during Socio-motor Improvisation.

    Science.gov (United States)

    Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

    2016-01-01

    Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

  13. Grain Growth Behavior in Sintered Nd-Fe-B Magnets

    Institute of Scientific and Technical Information of China (English)

    Liu Xianglian; Zhou Shouzeng

    2007-01-01

    The Nd2Fe14B grain growth behavior in sintered Nd-Fe-B magnets was quantitatively described. The effects of sintering temperature and time, and alloy powder size and its distribution on grain growth process were analyzed. Hence, possible grain growth mechanisms in these magnets were qualitatively discussed. The Nd2Fe14B grain growth proceeded at quite a high rate in the initial 0~1 h of sintering and from then onwards the grain growth rate decreased. A large average particle size or a wide particle size distribution of initial alloy powders was found to remarkably accelerate the grain growth process and even result in the occurrence of abnormal grain growth. On the basis of experimental results, two grain growth mechanisms were considered to operate during sintering of Nd-Fe-B magnets, that is, dissolution and re-precipitation of Nd2Fe14B particles, and Nd2Fe14B particle growth by coalescence. It was believed that Nd2Fe14B particle growth by coalescence not only produced a large average grain size and a wide grain size distribution, but also was the fundamental reason for the formation of abnormally large grains in the microstructure of sintered Nd-Fe-B magnets.

  14. Skipping the tracks. The experience of musical improvisation online

    OpenAIRE

    Roberto Zanetti

    2016-01-01

    The present article aims at analyzing the social and ontological effects of listening music online, with particular attention to the artistic practice of improvisation. In the first paragraph, I will briefly explain the essential concepts which ontology of music has traditionally counted on, and I will suggest an alternative theoretical approach, that I define as ontology of musical act. Then I will investigate the relation between recording practices and improvisation. In the final paragraph...

  15. Five Improvisations: aspetti nonlineari di un’improvvisazione

    Directory of Open Access Journals (Sweden)

    Mirio Cosottini

    2014-02-01

    Full Text Available This article aims to show how it is possible to enrich our knowledge of music through a linear and nonlinear analysis of sound. For this purpose, 1. I conduct a nonlinear analysis of a specific improvised music for winds and percussion, 2. I describe the sound characteristics of the invariants present in the improvisation, and 3. I finally show the relationship between linear and nonlinear properties of music.

  16. Emotional communicability in improvised music: the case of music therapists.

    Science.gov (United States)

    Gilboa, Avi; Bodner, Ehud; Amir, Dorit

    2006-01-01

    Musical improvisation is considered an efficient way to express emotions in music therapy. We examined the ability of music therapists (MTs) to convey emotions and their ability to accurately decode the emotional content of musical improvisations. Twenty-one MTs improvised on emotions they found difficult or easy to express in life, using or not using an emotional imagery technique. Fifty-five judges, some being MTs others nontherapists, evaluated the emotional content of the improvisations. Results showed that neither experience in therapy, nor musicianship or gender of the improviser were connected to emotional communicability (EC). Emotions that were reported as easy to express in life were communicated more accurately than those difficult to express in life. Emotional imagery did not facilitate and, to some extent, hindered emotional communicability. Some emotions were found to be difficult to express (e.g., anger) in comparison to others (e.g., happiness). MTs decoded the emotional content of the improvisations more accurately than nontherapists. Implications for the practical musical and emotional training of music therapists are discussed.

  17. L’appréciation esthétique de l’improvisation

    Directory of Open Access Journals (Sweden)

    Clément Canonne

    2014-02-01

    Full Text Available In this paper, I defend the idea that the way we listen to improvisation depends on the very ontological nature of improvisation. More specifically, I argue that improvisation calls for an intentionalist listening, by which the listener follows the improvisation as the creative process that it is. This listening attitude is made possible by the heightening of musical experience inherent to the improvisational situation and by the empathy linking the audience to the improvisers – both the consequences of improvisation’s ontological and temporal structure.

  18. Scaling critical behavior of superconductors at zero magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Calan, C. de; Nogueira, F.S. [Ecole Polytechnique (France). Centre de Physique Theorique

    2000-07-01

    Full text follows: We consider the scaling behavior in the critical domain of superconductors at zero external magnetic field. The Josephson's relation for a charged superfluid is proved without assuming the hyperscaling relation. On the other hand we discuss the dual Ginzburg-Landau model. In this dual model, due to the presence of two mass scales, a continuous family of non equivalent scalings can be defined. The relevant critical regimes are identified, and the corresponding critical exponents are predicted. (author)

  19. The effectiveness and influence of Vocal and Instrumental Improvisation in Music Therapy on children diagnosed with autism. Pilot Study

    Directory of Open Access Journals (Sweden)

    Sara Knapik-Szweda

    2015-09-01

    Full Text Available Autism is a developmental disorder which is difficult to recognize and diagnose. The present study examines the effectiveness of music therapy intervention based on improvisational techniques with the elements of Creative Music Therapy by Paul Nordoff and Clive Robbins and improvisational techniques by Tony Wigram (such as imitating, frameworking, dialogues, holding on developmentl of children with Autism (two boys diagnosed with autism - case 1. and case 2, especially in verbal and nonverbal communication, disturbance behavior patterns, cognitive and social-emotional areas. The results indicate a positive outcome in two music therapy observing tools: Scale I Child – Therapist Relationship in Coactive Musical Experience Rating Form and Scale II Musical Communicativeness Rating Form. The tables indicate the intensity of interaction between the therapist and the subject during the music therapy process (including communication skills, cognitive skills and behavior patterns. The results of case 1 are indicated in Scale I and Scale II and show a significant effect of improvisational music therapy. The important findings from the analysis of behavior in the sessions were Stability and confidence in interpersonal musical relationship, Activity relationship developing, (scale 1.. The results of the case 2. show small changes in musical behavior when it comes to Stability and confidence in interpersonal musical relationship, but in Activity relationship developing the indicators show a lot of changes between sessions. The results of the research indicate that music therapy intervention has a positive outcome and may be an effective method to increase functioning of children with autism

  20. Behavior of Compact Toroid in the External Magnetic Fields

    Science.gov (United States)

    Fukumoto, N.; Ioroi, A.; Nagata, M.; Uyama, T.

    1999-11-01

    We have investigated the possibility of refueling and density control of tokamak plasmas by the spheromak-type Compact Toroid (CT) injection in the JFT-2M tokamak in collaboration with JAERI. We demonstrated the CT injection into OH plasmas and observed the core penetration at B_T=0.8 T. The tokamak electron density increased ~0.2× 10^19m-3 at a rate of 2× 10^21m-3/s. We also observed the decrease of the CT velocity by the external magnetic field of the tokamak, which is applied across the CT acceleration region. We have examined the behavior of the CT translated in the external fields B_ext using the magnetic probes and the fast framing camera at Himeji Inst. of tech.. CT plasma in the acceleration region is deformed by the Lorentz force of Jg × B_ext, where Jg is the gun current for CT acceleration. The magnetic field structures of a long CT in the drift region has been revealed to be the mixed relaxed state of m=0 and m=1. Results from CT acceleration and injection in a transverse field will be presented.

  1. Magnetic switching behaviors of orbital states with different magnetic quantum numbers in Au/Fe/MgO multilayer system

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Kosuke, E-mail: kosuzuki@gunma-u.ac.jp; Takubo, Shota; Kato, Tadashi; Yamazoe, Masatoshi; Hoshi, Kazushi; Sakurai, Hiroshi [Department of Electronics and Informatics, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Homma, Yoshiya [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, 2145-2 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki 311-1313 (Japan); Itou, Masayoshi; Sakurai, Yoshiharu [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2014-08-18

    A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m| = 0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m| = 0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m| = 0, 2 and OSMH curve show switching behaviors of PMA.

  2. Bodystorming: effects of collaboration and familiarity on improvising contemporary dance.

    Science.gov (United States)

    Stevens, Catherine J; Leach, James

    2015-09-01

    In contemporary dance, cognitive events are not necessarily restricted "to the skin or skull of an individual" (Hutchins in Int Encycl Soc Behav Sci 2068-2072, 2001) but distributed across dancers during collaborative improvisation. There is some experimental evidence of greater output when people perform problem-solving tasks alone. However, when a task is challenging and paired participants are familiar with each other, pairwise and emergent outcomes are more plentiful than solo outcomes. We investigate these factors in the context of dance with the broad hypothesis that innovation is enhanced when dancers improvise together compared with when they improvise alone. Dancers (N = 10) in a professional company improvised for 2 min alone and then with another dancer. Dancer familiarity (familiar, unfamiliar) and task (expressive, non-expressive) were crossed (within-subjects). The improvisations were video-recorded over 2 h in the dancers' usual improvisation space. After each improvisation, the dancers: stated the number of movement ideas expressed and rated task ease, satisfaction, interest, novelty, originality and clarity. In both tasks, there was a tendency for self-report of a greater number of movement ideas expressed in familiar and unfamiliar pairs than alone. Ratings of task ease, satisfaction, interest, clarity, etc. were slightly higher in the unfamiliar pair condition. In the non-expressive task, ratings of the task were higher in pairs (M = 3.02, SD 0.82) than in the solo (M = 2.67, SD 0.96) condition. Distributed creativity, relational cognition and social facilitation are used to interpret the results.

  3. Metastable magnetic behavior in geometrically frustrated compound CePdAl

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.X. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan)]. E-mail: dxli@imr.tohoku.ac.jp; Nimori, S. [Tsukuba Magnet Laboratory, National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003 (Japan); Kitazawa, H. [Nanomaterials laboratory, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Shiokawa, Y. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan)

    2006-05-01

    We present the results of AC susceptibility, field-cooled and zero-field-cooled DC magnetization and magnetic relaxation measurements on an as-cast polycrystalline CePdAl sample. Irreversible magnetism, long-time magnetic relaxation effect and evident up-shift of the AC susceptibility peak with increasing frequency are observed at low temperatures. The mechanism of these 'spin-glass-like' metastable magnetic behaviors is discussed.

  4. A Three-Stage Process of Improvisation for Teamwork: Action Research

    Science.gov (United States)

    Hains-Wesson, Rachael; Pollard, Vikki; Campbell, Angela

    2017-01-01

    This study examines street performing arts students' responses to using improvisation for teamwork during a first year, non-placement, work-integrated learning (WIL) experience. The aim of the study was to investigate: (1) students' perceptions of improvisation and (2) ways in which to design teamwork assessments that utilise improvisation. Data…

  5. Teaching Improvisation in Elementary General Music: Facing Fears and Fostering Creativity

    Science.gov (United States)

    Whitcomb, Rachel

    2013-01-01

    Improvisation is a vital part of an elementary general music education. While some music teachers successfully include improvisation in music instruction, others have fears and face challenges when attempting improvisational activities in the classroom. This article acknowledges obstacles facing music educators when attempting to incorporate…

  6. Corrosion Behavior of Commercial Magnetic Refrigerant Gadolinium in Water

    Institute of Scientific and Technical Information of China (English)

    Zhang Zeyu; Long Yi; Wen Da; Ye Rongchang; Wan Farong

    2004-01-01

    Gadolinium(Gd) used as magnetic refrigerant always works in water environment.However, its poor corrosion resistance is serious impediment against wider application of Gd.In this paper, the corrosion behavior of two types of commercial Gd ( A, B both are 98.9 at.% pure) with the same oxygen content has been studied.The results show that the corrosion rate of A is 3.226 times higher than that of B in deionized water and 6.039 times in tap water.According to SEM, the different corrosion rate is because of the different distribution of impurity in matrix.In addition,NaOH solution was chosen as inhibitor to prevent Gd from being corroded successfully.No pitting corrosion and weight loss were observed for commercial Gd even after immersion for nearly 2000 h in NaOH solution.

  7. Clinical improvisation and the universe of musical idioms

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2001-01-01

    (please choose Danish language to see a German summary) The music therapy education at Aalborg University, Denmark, takes five years of full-time study to accomplish and contains many special disciplines. One of these is called intuitive music. It deals with improvisation training...... and with the creation of open compositions as well, which allow for improvisation in the playing process. The author discusses the relativity of musical idioms and points to the endeavours in new and experimental music to again connect music to everyday life and make it accessible for everybody. Parameter concepts......, which are focused upon one after another in practical exercises, and which can be used in analysing improvisations, are explained. Quotation aspects receive special attention and are seen as resulting from an inherent pluralism in the musical language. Through accepting this situation and through...

  8. Nonlinear dynamic behaviors of permanent magnet synchronous motors in electric vehicles caused by unbalanced magnetic pull

    Science.gov (United States)

    Xiang, Changle; Liu, Feng; Liu, Hui; Han, Lijin; Zhang, Xun

    2016-06-01

    Unbalanced magnetic pull (UMP) plays a key role in nonlinear dynamic behaviors of permanent magnet synchronous motors (PMSM) in electric vehicles. Based on Jeffcott rotor model, the stiffness characteristics of the rotor system of the PMSM are analyzed and the nonlinear dynamic behaviors influenced by UMP are investigated. In free vibration study, eigenvalue-based stability analysis for multiple equilibrium points is performed which offers an insight in system stiffness. Amplitude modulation effects are discovered of which the mechanism is explained and the period of modulating signal is carried out by phase analysis and averaging method. The analysis indicates that the effects are caused by the interaction of the initial phases of forward and backward whirling motions. In forced vibration study, considering dynamic eccentricity, frequency characteristics revealing softening type are obtained by harmonic balance method, and the stability of periodic solution is investigated by Routh-Hurwitz criterion. The frequency characteristics analysis indicates that the response amplitude is limited in the range between the amplitudes of the two kinds of equilibrium points. In the vicinity of the continuum of equilibrium points, the system hardly provides resistance to bending, and hence external disturbances easily cause loss of stability. It is useful for the design of the PMSM with high stability and low vibration and acoustic noise.

  9. Correlation Between Domain Behavior and Magnetic Properties of Materials

    Energy Technology Data Exchange (ETDEWEB)

    Leib, Jeffrey Scott [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    Correlation between length scales in the field of magnetism has long been a topic of intensive study. The long-term desire is simple: to determine one theory that completely describes the magnetic behavior of matter from an individual atomic particle all the way up to large masses of material. One key piece to this puzzle is connecting the behavior of a material's domains on the nanometer scale with the magnetic properties of an entire large sample or device on the centimeter scale. In the first case study involving the FeSiAl thin films, contrast and spacing of domain patterns are clearly related to microstructure and stress. Case study 2 most clearly demonstrates localized, incoherent domain wall motion switching with field applied along an easy axis for a square hysteresis loop. In case study 3, axis-specific images of the complex Gd-Si-Ge material clearly show the influence of uniaxial anisotropy. Case study 4, the only study with the sole intent of creating domain structures for imaging, also demonstrated in fairly simple terms the effects of increasing stress on domain patterns. In case study 5, it was proven that the width of magnetoresistance loops could be quantitatively predicted using only MFM. When all of the case studies are considered together, a dominating factor seems to be that of anisotropy, both magneticrostaylline and stress induced. Any quantitative bulk measurements heavily reliant on K coefficients, such as the saturation fields for the FeSiAl films, Hc in cases 1, 3, and 5, and the uniaxial character of the Gd5(Si2Ge2), transferred to and from the domain scale quite well. In-situ measurements of domain rotation and switching, could also be strongly correlated with bulk magnetic properties, including coercivity, Ms, and hysteresis loop shape. In most cases, the qualitative nature of the domain structures, when properly considered, matched quite well to what might have been expected

  10. Correlation Between Domain Behavior and Magnetic Properties of Materials

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey Scott Leib

    2003-05-31

    Correlation between length scales in the field of magnetism has long been a topic of intensive study. The long-term desire is simple: to determine one theory that completely describes the magnetic behavior of matter from an individual atomic particle all the way up to large masses of material. One key piece to this puzzle is connecting the behavior of a material's domains on the nanometer scale with the magnetic properties of an entire large sample or device on the centimeter scale. In the first case study involving the FeSiAl thin films, contrast and spacing of domain patterns are clearly related to microstructure and stress. Case study 2 most clearly demonstrates localized, incoherent domain wall motion switching with field applied along an easy axis for a square hysteresis loop. In case study 3, axis-specific images of the complex Gd-Si-Ge material clearly show the influence of uniaxial anisotropy. Case study 4, the only study with the sole intent of creating domain structures for imaging, also demonstrated in fairly simple terms the effects of increasing stress on domain patterns. In case study 5, it was proven that the width of magnetoresistance loops could be quantitatively predicted using only MFM. When all of the case studies are considered together, a dominating factor seems to be that of anisotropy, both magneticrostaylline and stress induced. Any quantitative bulk measurements heavily reliant on K coefficients, such as the saturation fields for the FeSiAl films, H{sub c} in cases 1, 3, and 5, and the uniaxial character of the Gd{sub 5}(Si{sub 2}Ge{sub 2}), transferred to and from the domain scale quite well. In-situ measurements of domain rotation and switching, could also be strongly correlated with bulk magnetic properties, including coercivity, M{sub s}, and hysteresis loop shape. In most cases, the qualitative nature of the domain structures, when properly considered, matched quite well to what might have been expected from theory and

  11. Emotional Intent Modulates The Neural Substrates Of Creativity: An fMRI Study of Emotionally Targeted Improvisation in Jazz Musicians.

    Science.gov (United States)

    McPherson, Malinda J; Barrett, Frederick S; Lopez-Gonzalez, Monica; Jiradejvong, Patpong; Limb, Charles J

    2016-01-04

    Emotion is a primary motivator for creative behaviors, yet the interaction between the neural systems involved in creativity and those involved in emotion has not been studied. In the current study, we addressed this gap by using fMRI to examine piano improvisation in response to emotional cues. We showed twelve professional jazz pianists photographs of an actress representing a positive, negative or ambiguous emotion. Using a non-ferromagnetic thirty-five key keyboard, the pianists improvised music that they felt represented the emotion expressed in the photographs. Here we show that activity in prefrontal and other brain networks involved in creativity is highly modulated by emotional context. Furthermore, emotional intent directly modulated functional connectivity of limbic and paralimbic areas such as the amygdala and insula. These findings suggest that emotion and creativity are tightly linked, and that the neural mechanisms underlying creativity may depend on emotional state.

  12. Clowning and improvisation in the ESL classroom : observations and suggestions

    OpenAIRE

    Sigríður Friðriksdóttir 1976

    2012-01-01

    This thesis examines how clowning and improvisation can help students in the ESL classroom. Clowning and improvisation was taught in a 6th grade ESL classroom and its effectiveness discussed. This thesis discusses the basics of clowning and why it is helpful when helping students feel at ease with speaking English. I also describe how it can be used and suggest drama-related games that are helpful. The conclusion is that drama-related games help students have fun while learning a new langu...

  13. Playing Together: Analyzing Jazz Improvisation to Improve the Multiframe

    Directory of Open Access Journals (Sweden)

    Zach Powers

    2016-06-01

    Full Text Available Musical terminology is often used when discussing narrative forms of art. However, this is seldom accompanied by a systematic application of musical concepts for use by artists in these other mediums. Comics, in particular, parallel music in terms of the multiframe, where various individual elements are perceived at once. Therefore, a useful analogy can be made between the multiframe and thematic and vertical musical construction. The interactivity among jazz musicians during a collective improvisation exemplifies this musical simultaneity, and this article creates an analogy between improvisation and narrative comics, deriving several analytical tools that can be used to inform the creation of more meaningful multiframes.

  14. Skipping the tracks. The experience of musical improvisation online

    Directory of Open Access Journals (Sweden)

    Roberto Zanetti

    2016-05-01

    Full Text Available The present article aims at analyzing the social and ontological effects of listening music online, with particular attention to the artistic practice of improvisation. In the first paragraph, I will briefly explain the essential concepts which ontology of music has traditionally counted on, and I will suggest an alternative theoretical approach, that I define as ontology of musical act. Then I will investigate the relation between recording practices and improvisation. In the final paragraph I will compare some features of musical recordings (suggested by Andrew Kania with those of technological devices that allow us to listen music online.

  15. Expertise in musical improvisation and creativity: the mediation of idea evaluation.

    Directory of Open Access Journals (Sweden)

    Oded M Kleinmintz

    Full Text Available The current study explored the influence of musical expertise, and specifically training in improvisation on creativity, using the framework of the twofold model, according to which creativity involves a process of idea generation and idea evaluation. Based on the hypothesis that a strict evaluation phase may have an inhibiting effect over the generation phase, we predicted that training in improvisation may have a "releasing effect" on the evaluation system, leading to greater creativity. To examine this hypothesis, we compared performance among three groups--musicians trained in improvisation, musicians not trained in improvisation, and non-musicians--on divergent thinking tasks and on their evaluation of creativity. The improvisation group scored higher on fluency and originality compared to the other two groups. Among the musicians, evaluation of creativity mediated how experience in improvisation was related to originality and fluency scores. It is concluded that deliberate practice of improvisation may have a "releasing effect" on creativity.

  16. Expertise in musical improvisation and creativity: the mediation of idea evaluation.

    Science.gov (United States)

    Kleinmintz, Oded M; Goldstein, Pavel; Mayseless, Naama; Abecasis, Donna; Shamay-Tsoory, Simone G

    2014-01-01

    The current study explored the influence of musical expertise, and specifically training in improvisation on creativity, using the framework of the twofold model, according to which creativity involves a process of idea generation and idea evaluation. Based on the hypothesis that a strict evaluation phase may have an inhibiting effect over the generation phase, we predicted that training in improvisation may have a "releasing effect" on the evaluation system, leading to greater creativity. To examine this hypothesis, we compared performance among three groups--musicians trained in improvisation, musicians not trained in improvisation, and non-musicians--on divergent thinking tasks and on their evaluation of creativity. The improvisation group scored higher on fluency and originality compared to the other two groups. Among the musicians, evaluation of creativity mediated how experience in improvisation was related to originality and fluency scores. It is concluded that deliberate practice of improvisation may have a "releasing effect" on creativity.

  17. The quasi-magnetic-hysteresis behavior of polydisperse ferrofluids with small coupling constant

    Energy Technology Data Exchange (ETDEWEB)

    Li Jian, E-mail: aizhong@swu.edu.cn [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Lin Yueqiang; Liu Xiaodong; Lin Lihua; Zhang Qingmei; Fu Jun; Chen Longlong [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Li Decai [School of Mechanical and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China)

    2012-12-15

    The magnetization behaviors of ferrofluids based on {gamma}-Fe{sub 2}O{sub 3}/Ni{sub 2}O{sub 3} composite nanoparticles of size about 11 nm have been investigated. The dipole coupling constant {lambda} of these particles is so small (0.43) that they cannot form aggregates through magnetic interaction alone. Experimental results have shown that for a polydisperse ferrofluid with a particle volume fraction of {phi}{sub V}=2.4%, the magnetization curve exhibits quasi-magnetic-hysteresis behavior, i.e., the demagnetization curve lies above the magnetization curve in a high field. However, for a more dilute {gamma}-Fe{sub 2}O{sub 3}/Ni{sub 2}O{sub 3} ferrofluid with {phi}{sub V}=0.94%, the magnetization curve does not show such behavior. According to the bidisperse model for polydisperse ferrofluids, these magnetization behaviors may be attributed to field-induced effects of self-assembled pre-existing chain-like aggregates. For such pre-existing chain-like aggregates, the orientation of the moments inside the particles is not co-linear, so that during the magnetization and demagnetization processes, their apparent magnetizations at the high-field limit are different. As a consequence, the magnetization curve of the ferrofluid with {phi}{sub V}=2.4% displays quasi-magnetic-hysteresis.

  18. A New Tool for Separating the Magnetic Mineralogy of Complex Mineral Assemblages from Low Temperature Magnetic Behavior

    Directory of Open Access Journals (Sweden)

    France Lagroix

    2017-07-01

    Full Text Available One timeless challenge in rock magnetic studies, inclusive of paleomagnetism and environmental magnetism, is decomposing a sample's bulk magnetic behavior into its individual magnetic mineral components. We present a method permitting to decompose the magnetic behavior of a bulk sample experimentally and at low temperature avoiding any ambiguities in data interpretation due to heating-induced alteration. A single instrument is used to measure the temperature dependence of remanent magnetizations and to apply an isothermal demagnetization step at any temperature between 2 and 400 K. The experimental method is validated on synthetic mixtures of magnetite, hematite, goethite as well as on natural loess samples where the contributions of magnetite, goethite, hematite and maghemite are successfully isolated. The experimental protocol can be adapted to target other iron bearing minerals relevant to the rock or sediment under study. One limitation rests on the fact that the method is based on remanent magnetizations. Consequently, a quantitative decomposition of absolute concentration of individual components remains unachievable without assumptions. Nonetheless, semi-quantitative magnetic mineral concentrations were determined on synthetic and natural loess/paleosol samples in order to validate and test the method as a semi-quantitative tool in environmental magnetism studies.

  19. High field magnetic behavior in Boron doped Fe2VAl Heusler alloys

    Science.gov (United States)

    Venkatesh, Ch.; Vasundhara, M.; Srinivas, V.; Rao, V. V.

    2016-11-01

    We have investigated the magnetic behavior of Fe2VAl1-xBx (x=0, 0.03, 0.06 and 0.1) alloys under high temperature and high magnetic field conditions separately. Although, the low temperature DC magnetization data for the alloys above x>0 show clear magnetic transitions, the zero field cooled (ZFC) and field cooled (FC) curves indicate the presence of spin cluster like features. Further, critical exponent (γ) deduced from the initial susceptibility above the Tc, does not agree with standard models derived for 3 dimensional long range magnetic systems. The deviation in γ values are consistent with the short range magnetic nature of these alloys. We further extend the analysis of magnetic behavior by carrying the magnetization measurements at high temperatures and high magnetic fields distinctly. We mainly emphasize the following observations; (i) The magnetic hysteresis loops show sharp upturns at lower fields even at 900 K for all the alloys. (ii) High temperature inverse susceptibility do not overlap until T=900 K, indicating the persistent short range magnetic correlations even at high temperatures. (iii) The Arrott's plot of magnetization data shows spontaneous moment (MS) for the x=0 alloy at higher magnetic fields which is absent at lower fields (magnetic heterogeneous phases which are not detected from the X-ray diffraction method.

  20. Effect of Pr–Ca substitution on the transport and magnetic behavior of LaMnO3 perovskite

    Indian Academy of Sciences (India)

    C M Thaker; S Rayaprol; Krushna Mavani; D S Rana; M S Sahasrabudhe; S I Patil; D G Kuberkar

    2002-05-01

    The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good example of these properties is (La1-2PrCa)MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in (for = 0.1, 0.15, 0.2), the c varies between 100 and 120 K with improvisation in metal–insulator transition. Interestingly, resistance increases with from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for understanding the structural, transport and magnetic properties are discussed in detail.

  1. Improvisational Acting Exercises and Their Potential Use in Family Counseling

    Science.gov (United States)

    Ruby, James R.; Ruby, Nanci Carol

    2009-01-01

    Expressive therapy interventions are a useful resource for counselors working with a wide range of presenting issues. This article illustrates a series of improvisational acting exercises that can be used within a family counseling context. Clear directions for specific exercises are provided, along with illustrative case examples.

  2. 342 Effects of Improvised Materials on Students' Achievement and ...

    African Journals Online (AJOL)

    FIRST LADY

    2011-01-18

    Jan 18, 2011 ... This paper is an empirical study aimed at finding out the effect of ... To determine the effect of improvised material on the students' ... and one in measurement evaluation. .... the teacher therefore is to find a method of communicating and .... written advance organizers on students achievement in Senior ...

  3. Generating Ideas in Jazz Improvisation: Where Theory Meets Practice

    Science.gov (United States)

    Hargreaves, Wendy

    2012-01-01

    Idea generation is an integral component of jazz improvising. This article merges theoretical origins and practical experiences through the examination of two seminal works from Pressing and Sudnow. A comparative analysis yields three common sources with distinct characteristics. The greater body of jazz literature supports this potential link…

  4. Generating Ideas in Jazz Improvisation: Where Theory Meets Practice

    Science.gov (United States)

    Hargreaves, Wendy

    2012-01-01

    Idea generation is an integral component of jazz improvising. This article merges theoretical origins and practical experiences through the examination of two seminal works from Pressing and Sudnow. A comparative analysis yields three common sources with distinct characteristics. The greater body of jazz literature supports this potential link…

  5. A Technique to Introduce Keyboard Improvisation in General Music

    Science.gov (United States)

    Wright, Jim

    2006-01-01

    All the general music books the author has seen teach the pentatonic scale, and achieve success with it, by having students play only on the piano's black keys. The trick to preventing this exercise from sounding simplistic or uninteresting is to teach improvisation in the A-flat Dorian mode. Using A-flat as the tonal center puts that center right…

  6. Neurophysiological correlates of musical creativity: The example of improvisation.

    Directory of Open Access Journals (Sweden)

    Skirtach I.A.

    2015-07-01

    Full Text Available Since the turn of this century, a substantial body of research has been published on the neuroscience of creativity. Now, it is necessary to study the neurophysiological correlates in true-to-life, professionally specific situations. The aim of our empirical research was to study the neurophysiological correlates of musical improvisation, a spontaneous creative activity. The participants were 136 right-handed practicing musicians aged 19 to 36 (102 males and 34 females, divided into two groups—professionals (56 people and amateurs (80 people. EEG signals were recorded in a resting state (eyes closed and during three types of internal musical activity (perceiving, mentally reproducing, and mentally improvising from 21 scalp electrodes according to the International 10-20 System. For statistical analysis, we used ANOVA and post hoc analysis. For the main neurophysiological correlates of musical creativity, we revealed higher values of EEG spectral power in the delta band and the dominance of long-distance functional cortical connections in the high-frequency bands. Variable neurophysiological correlates were differentiated according to emotions and the professional level of the musicians. The distinguishing EEG pattern in the professional musicians during improvisation was the predominant activation of the left- hemisphere cortical regions simultaneously with high interhemispheric integration in the high-frequency band along the “creativity axis.” The revealed neurophysiological correlates of musical creativity during improvisation included basic and variable components and were characterized by a specific frequency-spatial organization of bioelectric cortical activity in the musicians.

  7. Angelica Gets the Spirit Out: Improvisation, Epiphany and Transformation

    Science.gov (United States)

    Pignato, Joseph

    2013-01-01

    This article presents excerpts from a case study describing Angelica Dawson, a New York State music educator. Angelica makes improvisation a central part of her curricula in ways that transcend traditional offerings prevalent in American public schools. Qualitative research methods were used to document Angelica's work over the course of an…

  8. The causal inference of cortical neural networks during music improvisations.

    Science.gov (United States)

    Wan, Xiaogeng; Crüts, Björn; Jensen, Henrik Jeldtoft

    2014-01-01

    We present an EEG study of two music improvisation experiments. Professional musicians with high level of improvisation skills were asked to perform music either according to notes (composed music) or in improvisation. Each piece of music was performed in two different modes: strict mode and "let-go" mode. Synchronized EEG data was measured from both musicians and listeners. We used one of the most reliable causality measures: conditional Mutual Information from Mixed Embedding (MIME), to analyze directed correlations between different EEG channels, which was combined with network theory to construct both intra-brain and cross-brain networks. Differences were identified in intra-brain neural networks between composed music and improvisation and between strict mode and "let-go" mode. Particular brain regions such as frontal, parietal and temporal regions were found to play a key role in differentiating the brain activities between different playing conditions. By comparing the level of degree centralities in intra-brain neural networks, we found a difference between the response of musicians and the listeners when comparing the different playing conditions.

  9. Music Improvisation and Composition in the General Music Curriculum

    Science.gov (United States)

    Guderian, Lois Veenhoven

    2012-01-01

    This article describes an approach to general music where assignments in music improvisation and composition are embedded into the curriculum, that is, creative assignments are given as an outgrowth of curriculum content and directly related to instruction and activities in conceptual learning and skill development in the classroom. Such an…

  10. Maritime improvised explosive devices, modelling and large scale trials

    NARCIS (Netherlands)

    Heuvel, W. van den; Trouwborst, W.; Vader, J.A.A.

    2013-01-01

    Maritime Improvised Explosive Devices (MIEDs) such as small boats filled with explosives are likely to be a threat in future combat scenarios. For example the suicide attack against the USS Cole in Yemen (October 2000) has shown how disastrous MIEDs can be. With relatively simple means a complete co

  11. Predicting the Emplacement of Improvised Explosive Devices: An Innovative Solution

    Science.gov (United States)

    Lerner, Warren D.

    2013-01-01

    In this quantitative correlational study, simulated data were employed to examine artificial-intelligence techniques or, more specifically, artificial neural networks, as they relate to the location prediction of improvised explosive devices (IEDs). An ANN model was developed to predict IED placement, based upon terrain features and objects…

  12. The causal inference of cortical neural networks during music improvisations.

    Directory of Open Access Journals (Sweden)

    Xiaogeng Wan

    Full Text Available We present an EEG study of two music improvisation experiments. Professional musicians with high level of improvisation skills were asked to perform music either according to notes (composed music or in improvisation. Each piece of music was performed in two different modes: strict mode and "let-go" mode. Synchronized EEG data was measured from both musicians and listeners. We used one of the most reliable causality measures: conditional Mutual Information from Mixed Embedding (MIME, to analyze directed correlations between different EEG channels, which was combined with network theory to construct both intra-brain and cross-brain networks. Differences were identified in intra-brain neural networks between composed music and improvisation and between strict mode and "let-go" mode. Particular brain regions such as frontal, parietal and temporal regions were found to play a key role in differentiating the brain activities between different playing conditions. By comparing the level of degree centralities in intra-brain neural networks, we found a difference between the response of musicians and the listeners when comparing the different playing conditions.

  13. Bubble CPAP in Nigerian tertiary hospitals; Patented and improvised

    African Journals Online (AJOL)

    2016-09-12

    Sep 12, 2016 ... Nigeria.7,8 This has led to improvised CPAP devices for ... There is some evidence to suggest that the small vibrations produced ... South East. 85(35.9) ... Islam. 16(6.8). African traditional. Religion. 1(0.4). No response. 2(0.8).

  14. Behavior of leaching and precipitation of weathering crust ion-absorbed type by magnetic field

    Institute of Scientific and Technical Information of China (English)

    QIU Tingsheng; FANG Xihui; CUI Lifeng; FANG Yanxi

    2008-01-01

    With weathering crust Ion-Absorbed Type Rare Earth (IATRE) ores in southern Jiangxi as an example, rare earth percolation leaching and leaching solution precipitation process research were carried out under conditions of magnetic field. The effect on the rare earth leaching process such as magnetic field strength, magnetization time, magnetization manner, and other factors were discussed. The effect on the mother rare earth liquor sedimentation rate, purity, and crystallization behavior such as magnetic field strength, magnetization time, and magnetization manner were investigated. Leaching and precipitation mechanism of magnetization on IATRE were analyzed. The results showed that the magnetic treatment can improve leaching rate of weathering crust IATRE and the sedimentation rate, and reduce consumption of reagents.

  15. Novel behavior of magnetic flux lines in type II superconductors

    Science.gov (United States)

    Mohler, Gregory Allan

    cubic 3D XY model to simulate magnetic fields applied to a type II superconductor, tilted with respect to a cubic axis. Our model produces a "crossing lattices" state, wherein two distinct flux line lattices cross each other at right angles. We observe that the flux lines effectively form a "staircase" pattern in order to accommodate the crossing lattices structure. We also measure the helicity modulus as a function of temperature along the direction of each flux line lattice. We find that both lattices melt simultaneously, and that a small transverse field only slightly reduces the melting temperature. Similar behavior is found when this same model is treated within a simple mean field model.

  16. Thermo-magnetic behavior of the of the quark-gluon vertex

    CERN Document Server

    Ayala, Alejandro; Loewe, M; Tejeda-Yeomans, Maria Elena; Zamora, R

    2015-01-01

    The thermo-magnetic corrections to the quark-gluon vertex in the presence of a weak magnetic field are calculated in the frame of the Hard Thermal Loop approximation. The vertex satisfies a QED-like Ward identity with the quark self-energy calculated within the same approximation. It turns out that only the longitudinal vertex components get modified. The calculation provides a first principles result for the quark anomalous magnetic moment at high temperature in a weak magnetic field. The effective thermo-magnetic quark-gluon coupling shows a decreasing behavior as function of the field strength. This result supports the observation that the behavior of the effective quark-gluon coupling in the presence of a magnetic field is an important ingredient in order to understand the inverse magnetic catalysis phenomenon recently observed in the lattice QCD simulations.

  17. Joint Improvised-Threat Defeat Agency Needs to Improve Assessment and Documentation of Counter-Improvised Explosive Device Initiatives (Redacted)

    Science.gov (United States)

    2016-08-09

    Army (DCGS-A) project manager stating that JIDA leadership was looking to stand down its efforts completely and transition the current untested...Director, JIDA, to the program manager . The Instruction further differentiates program management agreements from the initiative decision...the Joint Improvised-Threat Defeat Agency (JIDA) effectively managed initiatives for rapid deployment on the battlefield. Specifically, we evaluated

  18. Magnetostrictive behaviors of Fe-Al(001 single-crystal films under rotating magnetic fields

    Directory of Open Access Journals (Sweden)

    Tetsuroh Kawai

    2016-05-01

    Full Text Available Magnetostrictive behaviors of Fe100−x − Alx(x = 0 − 30 at.%(001 single-crystal films under rotating magnetic fields are investigated along the two different crystallographic orientations, [100] and [110]. The behaviors of Fe and Fe90Al10 films show bath-tub like waveform along [100], easy magnetization axis, and triangular waveform along [110], hard magnetization axis, with respect to their four-fold magnetic anisotropy. On the other hand, the behaviors of Fe80Al20 film are different from those of Fe or Fe90Al10 film. The output of the film along [100] shows a strong magnetic field dependence. The Fe70Al30 film shows similar magnetostrictive behaviors along both [100] and [110] reflecting its magnetic properties, which are almost same for the both directions. The growth of ordered phase (B2 in Fe80Al20 and Fe70Al30 films is considered to have affected their magnetostrictive behaviors. The Al content dependence on λ100 and λ111 values shows similar tendency to that reported for the bulk samples but the values are slightly different. The Fe90Al10(001 single-crystal film shows a large magnetostriction along [100] under a very small magnetic field of 0.02 kOe, which is comparable to the saturated one, and changes the value abruptly in relation to the angle of applied magnetic field.

  19. Microcapillary flow behavior of magnetic nanofluids in the presence of plate shaped bentonite particles

    Science.gov (United States)

    Parmar, Mayur; Virpura, Hiral; Patel, Rajesh

    2013-04-01

    Plate shaped bentonite particles of size ˜600 nm and thickness ˜2 nm are dispersed in a magnetic nanofluid. Magnetic field dependent flow behavior of this composite suspension is studied using a horizontal microcapillary placed between the poles of an electromagnet. The plate shaped bentonite particle produces extra hindrance to the flow under the application of moderate magnetic field and produces an enhanced magnetoviscous effect. 75% volume concentration of bentonite produces eight times larger change in magnetic field dependent viscosity than does the pure magnetic nanofluid. Hindrance to the flow is due to the chain like structure of magnetic nanoparticles, tumbling and rotational motion of bentonite particles and interaction between magnetic and bentonite particles. The field-induced structures are also observed using an optical microscope. Results offer several advantages over the inverse MR effect as well as to study the motion of biological cells and tissues under the effect of magnetic field.

  20. Single molecule magnet behavior of a pentanuclear Mn-based metallacrown complex: solid state and solution magnetic studies.

    Science.gov (United States)

    Zaleski, Curtis M; Tricard, Simon; Depperman, Ezra C; Wernsdorfer, Wolfgang; Mallah, Talal; Kirk, Martin L; Pecoraro, Vincent L

    2011-11-21

    The magnetic behavior of the pentanuclear complex of formula Mn(II)(O(2)CCH(3))(2)[12-MC(Mn(III)(N)shi)-4](DMF)(6), 1, was investigated using magnetization and magnetic susceptibility measurements both in the solid state and in solution. Complex 1 has a nearly planar structure, made of a central Mn(II) ion surrounded by four peripheral Mn(III) ions. Solid state variable-field dc magnetic susceptibility experiments demonstrate that 1 possesses a low value for the total spin in the ground state; fitting appropriate expressions to the data results in antiferromangetic coupling both between the peripheral Mn(III) ions (J = -6.3 cm(-1)) and between the central Mn(II) ion and the Mn(III) ones (J' = -4.2 cm(-1)). In order to obtain a reasonable fit, a relatively large single ion magnetic anisotropy (D) value of 1 cm(-1) was necessary for the central Mn(II) ion. The single crystal magnetization measurements using a microsquid array display a very slight opening of the hysteresis loop but only at a very low temperature (0.04 K), which is in line with the ac susceptibility data where a slow relaxation of the magnetization occurs just around 2 K. In frozen solution, complex 1 displays a frequency dependent ac magnetic susceptibility signal with an energy barrier to magnetization reorientation (E) and relaxation time at an infinite temperature (τ(o)) of 14.7 cm(-1) and 1.4 × 10(-7) s, respectively, demonstrating the single molecule magnetic behavior in solution.

  1. Behavior of moving plasma in solenoidal magnetic field in a laser ion source

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, S., E-mail: ikeda.s.ae@m.titech.ac.jp [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502 (Japan); Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0108 (Japan); Takahashi, K. [Department of Electrical Engineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2137 (Japan); Okamura, M. [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States); Horioka, K. [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502 (Japan)

    2016-02-15

    In a laser ion source, a solenoidal magnetic field is useful to guide the plasma and to control the extracted beam current. However, the behavior of the plasma drifting in the magnetic field has not been well understood. Therefore, to investigate the behavior, we measured the plasma ion current and the total charge within a single pulse in the solenoid by changing the distance from the entrance of the solenoid to a detector. We observed that the decrease of the total charge along the distance became smaller as the magnetic field became larger and then the charge became almost constant with a certain magnetic flux density. The results indicate that the transverse spreading speed of the plasma decreased with increasing the field and the plasma was confined transversely with the magnetic flux density. We found that the reason of the confinement was not magnetization of ions but an influence induced by electrons.

  2. Behavior of moving plasma in solenoidal magnetic field in a laser ion source

    Science.gov (United States)

    Ikeda, S.; Takahashi, K.; Okamura, M.; Horioka, K.

    2016-02-01

    In a laser ion source, a solenoidal magnetic field is useful to guide the plasma and to control the extracted beam current. However, the behavior of the plasma drifting in the magnetic field has not been well understood. Therefore, to investigate the behavior, we measured the plasma ion current and the total charge within a single pulse in the solenoid by changing the distance from the entrance of the solenoid to a detector. We observed that the decrease of the total charge along the distance became smaller as the magnetic field became larger and then the charge became almost constant with a certain magnetic flux density. The results indicate that the transverse spreading speed of the plasma decreased with increasing the field and the plasma was confined transversely with the magnetic flux density. We found that the reason of the confinement was not magnetization of ions but an influence induced by electrons.

  3. A summary of the quench behavior of B&W 1 m collider quadrupole model magnets

    Energy Technology Data Exchange (ETDEWEB)

    Rey, C.M.; Xu, M.F.; Hlasnicek, P.; Kelley, J.P.; Dixon, K.; Savignano, J.; Letterman, S.; Craig, P.; Maloney, J.; Boyes, D. [Babcock & Wilcox, Lynchburg, VA (United States)] [and others

    1994-12-31

    In order to evaluate the quench performance of a B&W-Siemens designed quadrupole magnet at the earliest possible stage, a model magnet program was developed at B&W for the support of the Superconducting Super Collider. The authors report the quench performance, training behavior, and the ramp rate dependence for the QSH-801 through QSH-804 series of short (1.2 meter) quadrupole model magnets.

  4. Polar Behavior in a Magnetic Perovskite Via A-Site Size Disorder

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chul-Hong [ORNL; Singh, David J [ORNL

    2008-01-01

    We elucidate a mechanism for obtaining polar behavior in magnetic perovskites based on A-site disorder and demonstrate this mechanism by density functional calculations for the double perovskite (La,Lu)MnNiO{sub 6} with Lu concentrations at and below 50%. We show that this material combines polar behavior and ferromagnetism. The mechanism is quite general and may be applicable to a wide range of magnetic perovskites.

  5. Polar Behavior in a Magnetic Perovskite from A-Site Size Disorder: A Density Functional Study

    Science.gov (United States)

    Singh, D. J.; Park, Chul Hong

    2008-02-01

    We elucidate a mechanism for obtaining polar behavior in magnetic perovskites based on A-site disorder and demonstrate this mechanism by density functional calculations for the double perovskite (La,Lu)MnNiO6 with Lu concentrations at and below 50%. We show that this material combines polar behavior and ferromagnetism. The mechanism is quite general and may be applicable to a wide range of magnetic perovskites.

  6. Musical answerability : a theory on the relationship between music therapy improvisation and the phenomenon of action

    OpenAIRE

    Stensæth, Karette

    2007-01-01

    What is the relationship between music therapy improvisation and the phenomenon of action? This thesis seeks to build a theory on how actions manifest themselves in music therapy improvisation and how they are cultivated and thought about by music therapists. A video recorded excerpt of a music therapy improvisation with a multi-handicapped client is used in order to produce the empirical material, and the theoretical material includes discussions on relevant established theories. New theo...

  7. Enhancing Teaching, Adaptability and Presentation Skills through Improvisational Theater

    Directory of Open Access Journals (Sweden)

    Thomas J. Marlowe

    2014-10-01

    Full Text Available Improvisational theater, creative role-playing and open-ended scenarios are increasingly being used as ways to emphasize the importance of combining planning with flexibility and evolution to respond to changes in context. These skills and capabilities are extremely valuable in teaching, especially for strengthening communication and interpersonal skills, as well as the capacity for critical thinking and problem solving. Further, this combination of planning with flexibility is also a major theme of agile software development and a number of other problem-solving domains, and in the collaborative development of intellectual property in technical areas. With improvisation, the plan becomes less of a fixed framework, and more of a guideline. In software engineering, it becomes a mutable structure on which to hang goals and objectives, progress, processes, artifacts, and properties. In this submission, we explore the ramifications of this approach.

  8. Clinical improvisation and the universe of musical idioms

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2001-01-01

    (please choose Danish language to see a German summary) The music therapy education at Aalborg University, Denmark, takes five years of full-time study to accomplish and contains many special disciplines. One of these is called intuitive music. It deals with improvisation training and with the cr......(please choose Danish language to see a German summary) The music therapy education at Aalborg University, Denmark, takes five years of full-time study to accomplish and contains many special disciplines. One of these is called intuitive music. It deals with improvisation training...... conscious working with this aspect the author believes that the problem of relativity can be mastered. At the end of the article, the parameter view is illustrated with a clinical example....

  9. Improvisation and co-expression in explorative digital music systems

    DEFF Research Database (Denmark)

    Hansen, Anne-Marie Skriver

    action, collaboration and musical expression it was possible to narrow down the interesting moments where co-expression happens in music improvisation. The qualitative video microanalysis of player communication and ongoing negotiation of musical expression informed the quantitative analysis of logged...... simultaneous and contrasting play forms. However, results from the quantitative analysis also show that players applied their social skills to the musical context: they were able to adapt quickly to each others’ changes in tempo and they were very flexible in terms of the distribution of musical roles. Duets...... were most successful in their engagement in musical relationships when they introduced each other to short, repeated and slightly varied phrases. Furthermore results from the qualitative analysis show that players were very creative in their improvisation of musical content. Most duets managed...

  10. Oral Communication in ESL Through Improvisations, Playwriting And Rehearsals

    Directory of Open Access Journals (Sweden)

    Chamkaur Gill

    2013-01-01

    Full Text Available The application of drama strategies which focus more on meaning than on form can provide an impetus for ESL learners to be more confident about speaking, thereby increasing the quantity of their spoken English. This paper discusses existing research and the author’s own experiences in an attempt to highlight the positive effects of improvisations, playwriting and rehearsals on the oral output of learners in relation to communicative English.

  11. Maritime Improvised Explosive Devices: A Threat Based Technology Study

    Science.gov (United States)

    2015-06-12

    ROV Remotely Operated Vehicle ix RSP Render Safe Procedure SIPRNet Secret Internet Protocol Router Network SLOC Sea Lines of Communication TTP...ways to inflict terrorism at sea, such as piracy and maritime improvised explosive devices (MIED). “MIEDs can take many forms, which can include...natural disaster, and we cannot intercede when whole societies are torn asunder by slavery, weapons of mass destruction, drugs, and piracy . Without sea

  12. Neurophysiological correlates of musical creativity: The example of improvisation.

    OpenAIRE

    Skirtach I.A.

    2015-01-01

    Since the turn of this century, a substantial body of research has been published on the neuroscience of creativity. Now, it is necessary to study the neurophysiological correlates in true-to-life, professionally specific situations. The aim of our empirical research was to study the neurophysiological correlates of musical improvisation, a spontaneous creative activity. The participants were 136 right-handed practicing musicians aged 19 to 36 (102 males and 34 females), divided into two grou...

  13. Neurophysiological correlates of musical creativity: the example of improvisation

    OpenAIRE

    2015-01-01

    Since the turn of this century, a substantial body of research has been published on the neuroscience of creativity. Now, it is necessary to study the neurophysiological correlates in true-to-life, professionally specific situations. The aim of our empirical research was to study the neurophysiological correlates of musical improvisation, a spontaneous creative activity. The participants were 136 right-handed practicing musicians aged 19 to 36 (102 males and 34 females), divided into two grou...

  14. Behavior of antiferromagnetic MnCoSi in a magnetic field under pressure

    Energy Technology Data Exchange (ETDEWEB)

    Zavorotnev, Yu.D., E-mail: zavorotnev.yurii@gmail.com [Donetsk Institute for Physics and Engineering, NAS of Ukraine, 72 R. Luxemburg St., 83114 Donetsk (Ukraine); Medvedeva, L.I.; Todris, B.M.; Dvornikov, E.A. [Donetsk Institute for Physics and Engineering, NAS of Ukraine, 72 R. Luxemburg St., 83114 Donetsk (Ukraine); Popova, O.Yu. [Donetsk National Technical University, 58 Artema St., 83001 Donetsk (Ukraine)

    2011-11-15

    Experimental data on magnetization of the antiferromagnetic (AFM) polycrystalline samples in the temperature range of 20-300 K, for pressures of 2 kbar and in magnetic field of 300 kOe, are presented in the paper. In the fields of 250 kOe, the magnetization curve demonstrates a jump explained by exchange-interaction sign change. In the region of 50-70 kOe, on the differential susceptibility versus magnetic field curve, there is a break of the 2nd order corresponding to the anomalous behavior of the magnetization. The obtained results were processed on the basis of the phenomenological Landau theory. It is shown that the ferromagnetic vector occurrence is forced during the formation of AFM spiral structure. The behavior of thermodynamic potential factors has been determined. Three more anomalies have been revealed and explained by a jump-like magnetization change of the Co-subsystem. - Highlights: > MnCoSi alloy is studied under pressure of 2 kbar, at magnetic field of 300 kOe. > Temperature range was 20-300 K. > Pressure-dependent magnetization jump is due to sign change of exchange interaction. > Magnetization anomaly is conditioned by intersection of the lowest levels of Co ions. > Temperature extrema at magnetization are realized within the jump region.

  15. A Model to Describe the Magnetomechanical Behavior of Martensite in Magnetic Shape Memory Alloy

    Directory of Open Access Journals (Sweden)

    Zaoyang Guo

    2014-01-01

    Full Text Available A model to describe the constitutive behavior of magnetic shape memory alloy composed with pure martensite is proposed based on the analysis of variants reorientation. A hyperbolic tangent expression is given to describe the variants transition during magnetic and mechanical loading process. The main features of magnetic shape memory alloy, such as pseudoelastic and partially pseudoelastic behavior as well as minor hysteretic loops, can be successfully replicated with the proposed model. A good agreement is achieved between calculated results and experimental data for NiMnGa single crystal.

  16. Listeners' and Performers' Shared Understanding of Jazz Improvisations.

    Science.gov (United States)

    Schober, Michael F; Spiro, Neta

    2016-01-01

    This study explores the extent to which a large set of musically experienced listeners share understanding with a performing saxophone-piano duo, and with each other, of what happened in three improvisations on a jazz standard. In an online survey, 239 participants listened to audio recordings of three improvisations and rated their agreement with 24 specific statements that the performers and a jazz-expert commenting listener had made about them. Listeners endorsed statements that the performers had agreed upon significantly more than they endorsed statements that the performers had disagreed upon, even though the statements gave no indication of performers' levels of agreement. The findings show some support for a more-experienced-listeners-understand-more-like-performers hypothesis: Listeners with more jazz experience and with experience playing the performers' instruments endorsed the performers' statements more than did listeners with less jazz experience and experience on different instruments. The findings also strongly support a listeners-as-outsiders hypothesis: Listeners' ratings of the 24 statements were far more likely to cluster with the commenting listener's ratings than with either performer's. But the pattern was not universal; particular listeners even with similar musical backgrounds could interpret the same improvisations radically differently. The evidence demonstrates that it is possible for performers' interpretations to be shared with very few listeners, and that listeners' interpretations about what happened in a musical performance can be far more different from performers' interpretations than performers or other listeners might assume.

  17. Jazz Guitar Improvisation: Beginning with Guide-Tones

    Directory of Open Access Journals (Sweden)

    Daniel Andersen

    2010-12-01

    Full Text Available This article discusses an approach to teaching linear improvisation to beginning jazz guitarists through the function of voice leading in harmonic progressions. The student may gain a clear understanding of improvising melodies by establishing clear visual and aural relationships between the chordal and melodic textures. Three dominant 7th chord voicings are introduced and applied to a twelve bar blues progression in F major. After learning the rhythm guitar accompaniment, single note guide tones consisting of the flat 7th and 3rd chord tones of each dominant seventh chord are extracted from the chord voicings and applied in a melodic texture following chromatic voice leading principles within the harmonic progression. Musicality within the exercises is increased by the addition of a series of rhythmic variations that are applied to the guide-tone lines. Continuing with the concept, full dominant seventh arpeggios are introduced in order to expand the available note choices as a way to build a solid foundation for improvising within harmonic progressions prior to using diatonic scales.

  18. Listeners' and performers' shared understanding of jazz improvisations

    Directory of Open Access Journals (Sweden)

    Michael F Schober

    2016-11-01

    Full Text Available This study explores the extent to which a large set of musically experienced listeners share understanding with a performing saxophone-piano duo, and with each other, of what happened in three improvisations on a jazz standard. In an online survey, 239 participants listened to audio recordings of three improvisations and rated their agreement with 24 specific statements that the performers and a jazz-expert commenting listener had made about them. Listeners endorsed statements that the performers had agreed upon significantly more than they endorsed statements that the performers had disagreed upon, even though the statements gave no indication of performers' levels of agreement. The findings show some support for a more-experienced-listeners-understand-more-like-performers hypothesis: Listeners with more jazz experience and with experience playing the performers' instruments endorsed the performers' statements more than did listeners with less jazz experience and experience on different instruments. The findings also strongly support a listeners-as-outsiders hypothesis: Listeners' ratings of the 24 statements were far more likely to cluster with the commenting listener's ratings than with either performer's. But the pattern was not universal; particular listeners even with similar musical backgrounds could interpret the same improvisations radically differently. The evidence demonstrates that it is possible for performers' interpretations to be shared with very few listeners, and that listeners’ interpretations about what happened in a musical performance can be far more different from performers’ interpretations than performers or other listeners might assume.

  19. Non-linear magnetic behavior around zero field of an assembly of superparamagnetic nanoparticles.

    Science.gov (United States)

    de Montferrand, Caroline; Lalatonne, Yoann; Bonnin, Dominique; Motte, Laurence; Monod, Philippe

    2012-05-21

    The MIAplex® device is a miniaturized detector, devoted to the high sensitive detection of superparamagnetic nanoprobes for multiparametric immunoassays. It measures a signal corresponding to the second derivative of the magnetization around zero field. Like any new technology, the real success of the MIAplex® detector can only be exploited through a deep understanding of the magnetic signature. In this letter, we study the magnetic behavior around zero-field of diluted lab-made and commercial ferrofluids by comparing together conventional SQUID magnetization and MIAplex® signature.

  20. Behavior of magnetic field and eddy current in a magnetostriction based bi-layered composite

    Directory of Open Access Journals (Sweden)

    Kewei Zhang

    2016-12-01

    Full Text Available In this paper, we presented a theoretical method for studying the behavior of magnetic field intensity and eddy current inside a magnetostriction based bi-layered composite. Firstly, the mathematical model for the electromagnetic field in the composite was established. Then, the governing equation for determining the magnetic field intensity and eddy current was solved. Furthermore, the effect of the composite’s conductivity on the magnetic field intensity and eddy current were discussed. Lastly, by comparing with the well known R.L. Stoll’s equation, the magnetic field intensity calculated based on our equation showed a less than 0.5% error.

  1. Behavior of magnetic field and eddy current in a magnetostriction based bi-layered composite

    Science.gov (United States)

    Zhang, Kewei; Zhang, Kehao; Liu, Huifeng; Li, Junlin

    2016-12-01

    In this paper, we presented a theoretical method for studying the behavior of magnetic field intensity and eddy current inside a magnetostriction based bi-layered composite. Firstly, the mathematical model for the electromagnetic field in the composite was established. Then, the governing equation for determining the magnetic field intensity and eddy current was solved. Furthermore, the effect of the composite's conductivity on the magnetic field intensity and eddy current were discussed. Lastly, by comparing with the well known R.L. Stoll's equation, the magnetic field intensity calculated based on our equation showed a less than 0.5% error.

  2. Electron Transport Behavior in a Mirror Magnetic Field and a Non-uniform Electric Field

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-Hong; LIU Zu-Li; YAO Kai-Lun; WEI He-Lin; LIU Hong-Xiang

    2001-01-01

    The behaviors of electrons as they move under the influence of mirror magnetic field and non-uniform electric field in a positive column of helium radio frequency gas discharge are studied by Monte Carlo simulation. Some types of collisions (elastic, excitation and ionization collisions) are considered. Graphs showing how the electron density,electron energy, electron current density, collision rate and the electron-scattering angular distribution are affected by the mirror magnetic field are presented. The results indicate that the mirror magnetic field can control the electron transport behavior in the positive column. In the presence of the mirror magnetic field, the electrons are restricted in the middle part of the positive column, and the electron density is greatly increased. The electron collision rate and the electron current density are enhanced in the middle region, and the electron-scattering angles are extended by the mirror magnetic tields. These results are in good agreement with experimental results.

  3. Microcapillary flow behavior of magnetic nanofluids in the presence of plate shaped bentonite particles

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, Mayur; Virpura, Hiral [Department of Physics, Bhavnagar University, Bhavnagar 364001, GJ (India); Patel, Rajesh, E-mail: rjp@bhavuni.edu [Department of Physics, Bhavnagar University, Bhavnagar 364001, GJ (India); Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States)

    2013-04-15

    Plate shaped bentonite particles of size ∼600 nm and thickness ∼2 nm are dispersed in a magnetic nanofluid. Magnetic field dependent flow behavior of this composite suspension is studied using a horizontal microcapillary placed between the poles of an electromagnet. The plate shaped bentonite particle produces extra hindrance to the flow under the application of moderate magnetic field and produces an enhanced magnetoviscous effect. 75% volume concentration of bentonite produces eight times larger change in magnetic field dependent viscosity than does the pure magnetic nanofluid. Hindrance to the flow is due to the chain like structure of magnetic nanoparticles, tumbling and rotational motion of bentonite particles and interaction between magnetic and bentonite particles. The field-induced structures are also observed using an optical microscope. Results offer several advantages over the inverse MR effect as well as to study the motion of biological cells and tissues under the effect of magnetic field. -- Highlights: ► Dispersed plate shaped bentonite particles in magnetic fluids to study capillary viscosity. ► Increased viscosity is due to the hindrance to the rotation of the bentonite particles. ► Increase in viscosity is five times larger for bentonite particles than the pure magnetic fluids. ► This is a new kind of magnetoviscous effect, dispersing anisotropic particles in magnetic fluids.

  4. Bilayer Ising system designed with half-integer spins: Magnetic hysteresis, compensation behaviors and phase diagrams

    Science.gov (United States)

    Kantar, Ersin

    2016-08-01

    In this paper, within the framework of the effective-field theory with correlation, mixed spin-1/2 and spin-3/2 bilayer system on a square lattice is studied. The characteristic behaviors for the magnetic hysteresis, compensation types and phase diagrams depending on effect of the surface and interface exchange parameters as well as crystal field are investigated. From the behavior of total magnetization as a function of the magnetic field and temperature, we obtain the single, double and triple hysteresis loops and the L-, Q-, P-, S-, and N-type compensation behaviors in the system. Moreover, we detect the more effective the J1 and crystal field parameters on the bilayer Ising model according to the behaviors of the phase diagrams.

  5. Critical behavior of zero-field magnetic fluctuations in perpendicularly magnetized thin films

    Science.gov (United States)

    Balk, A. L.; Stiles, M. D.; Unguris, J.

    2014-11-01

    We use video-rate magneto-optical Kerr effect microscopy to study zero-field magnetic fluctuations in a perpendicularly magnetized cobalt film at room temperature, prepared near a spin reorientation transition. Globally, the film has zero net moment but local areas continually undergo thermal magnetic fluctuations between saturated states. Position resolved hysteresis loops show the fluctuations occur at sample locations close to the spin reorientation transition. Furthermore, nearby fluctuations interact magnetostatically, acting to maintain the overall zero net magnetization. The measured scaling exponent of the fluctuation areas τ is consistent with 4 /3 .

  6. Rheological behavior of cellulose nanowhisker suspension under magnetic field.

    Science.gov (United States)

    Kim, Dah Hee; Song, Young Seok

    2015-08-01

    We investigated the influence of a magnetic field on the rheology of cellulose nanowhisker (CNW) suspension. The morphology of CNWs was analyzed by using polarized optical microscopy (POM) and transmission electron microscopy (TEM). The findings show that the application of the magnetic field leads to an increase in shear viscosity and viscoelastic properties such as the storage and loss moduli. A mesoscale constitutive model was adopted to provide better understanding of the effect of particle concentration on the orientation of CNWs. As the concentration increases, the steric interaction between particles becomes significant and the effect of the applied magnetic field on the internal structure of the CNW suspension was reduced. In addition, the size distribution of CNWs was characterized using a light scattering method. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Viscosity behavior of magnetic suspensions in fluid-assisted finishing

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.

  8. Magnetic behavior of Gd4Co3 metallic glass

    Science.gov (United States)

    Zhang, Ji Liang; Zheng, Zhi Gang; Cao, Wen Huan; Shek, Chan Hung

    2013-01-01

    Metallic glass was successfully fabricated of the Gd4Co3 intermetallic composition. Analysis of the magnetization-temperature data showed that the moment per Gd atom was larger than its theoretical value and indicated the contribution from the Co moment. The maximum magnetic entropy change of glassy Gd4Co3 was determined as -7.2 J kg-1 K-1 at 50 kOe and -3.8 J kg-1 K-1 at 20 kOe, which are both much larger than those of its crystalline state.

  9. The corrosion behavior of Nd2Fe14B and SmCo5 magnets.

    Science.gov (United States)

    Kitsugi, A; Okuno, O; Nakano, T; Hamanaka, H; Kuroda, T

    1992-12-01

    Rare earth magnets have corrosive problems associated with their use in prostheses in various fields including orthodontics. The purpose of this study is to investigate the corrosion behavior of an Nd2Fe14B magnet and a SmCo5 magnet in an oral environment. The relations among the attractive force changes, the released elements, the weight changes and the anodic polarization measurements of the magnets were examined under immersions in 1% NaCl, 1% lactic acid, 0.05% HCl, 0.1% Na2S and Greenwood's artificial saliva at 37 degrees C for forty-two days. The results showed that the rare earth magnets underwent high corrosive assaults and large attractive force reductions by the immersions in 1% lactic acid and 0.05% HCl. The problem of corrosion of the magnets could be overcome by sealing them within laser-welded stainless steel capsules.

  10. Novel collective magnetic relaxation phenomena in manganites: a spin-glass behavior?

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, J. [Departamento de Fisica Aplicada, Universidad de Santiago de Compostela, E-15782-Santiago de Compostela (Spain)]. E-mail: farivas@usc.es; Rivadulla, F. [Departamento de Quimica-Fisica, Universidad de Santiago de Compostela, E-15782-Santiago de Compostela (Spain); Lopez-Quintela, M.A. [Departamento de Quimica-Fisica, Universidad de Santiago de Compostela, E-15782-Santiago de Compostela (Spain)

    2004-12-31

    Here we address many of the fundamental open questions regarding the glassy behavior of the magnetic/electronic phase segregated state in rare earth perovskites. Magnetic relaxation (AC/DC) support a scenario in which collective effects (memory, ageing, etc.) can be understood as due to intercluster interactions. We propose that the phase segregated state (PSS) constitutes a sort of self-generated assembly of magnetic clusters in which the magnetic interaction introduces collectivity among them. The strength of the interactions can be tuned by composition and/or magnetic field, through the control of the size and concentration of the magnetic clusters. These results are general, applicable to other systems close to a localized to itinerant transition, like cobaltates, cuprates, etc.

  11. Novel collective magnetic relaxation phenomena in manganites: a spin-glass behavior?

    Science.gov (United States)

    Rivas, J.; Rivadulla, F.; López-Quintela, M. A.

    2004-12-01

    Here we address many of the fundamental open questions regarding the glassy behavior of the magnetic/electronic phase segregated state in rare earth perovskites. Magnetic relaxation (AC/DC) support a scenario in which collective effects (memory, ageing, etc.) can be understood as due to intercluster interactions. We propose that the phase segregated state (PSS) constitutes a sort of self-generated assembly of magnetic clusters in which the magnetic interaction introduces collectivity among them. The strength of the interactions can be tuned by composition and/or magnetic field, through the control of the size and concentration of the magnetic clusters. These results are general, applicable to other systems close to a localized to itinerant transition, like cobaltates, cuprates, etc.

  12. Numerical calculation of magnetization behavior for Co nanowire array

    Institute of Scientific and Technical Information of China (English)

    ZHONG Ke-hua; HUANG Zhi-gao; CHEN Zhi-gao; FENG Qian; YANG Yan-min

    2008-01-01

    Based on Monte Carlo method,the hysteresis loops for both individual Co nanowires and their array were simulated,and the influence of the strength of the dipolar interaction on the macroscopical magnetic properties of Co nanowire array was investigated.The simulated results indicate that the coercivity approximately increases linearly with the increase of the strength coeffcient of the dipolar interaction.The interwire dipole interaction between wires tends to develop a magnetic easy axis perpendicular to the wire axis.In the magnetic reversal process,competition between the interwire dipolar interaction and the shape anisotropy of individual wires which forces the moments to orient along the axis makes the magnetic reversal of the array different from that of individual wire.For applied field parallel to wire axis,the coercivity of nanowire array increases rapidly with the increase of the nearest-neighbor interwire distance,and approximately increases linearly with the increase of the strength coefficient of the dipolar interaction for the fixed diameter and the nearest-neighbor interwire distance.While for applied field perpendicular to wire axis,in contrast,the coercivity decreases with increasing the nearest-neighbor interwire distance,and nearly remains a constant with the increase of the strength coefficient of the dipolar interaction.

  13. Magnetization behavior of ferrofluids with cryogenically imaged dipolar chains

    NARCIS (Netherlands)

    Klokkenburg, M.; Erne, B.H.; Mendelev, V.; Ivanov, A.O.

    2008-01-01

    Theories and simulations have demonstrated that field-induced dipolar chains affect the static magnetic properties of ferrofluids. Experimental verification, however, has been complicated by the high polydispersity of the available ferrofluids, and the morphology of the dipolar chains was left to th

  14. Magnetic behavior of clusters of ferromagnetic transition metals

    DEFF Research Database (Denmark)

    Khanna, S. N.; Linderoth, Søren

    1991-01-01

    The effective magnetic moments of small iron and cobalt clusters have been calculated by assuming that the clusters undergo superparamagnetic relaxation. The effective moments per atom are found to be much below the bulk values, even at low temperatures (100 K). They increase with particle size a...

  15. Magnetization behavior of ferrofluids with cryogenically imaged dipolar chains

    NARCIS (Netherlands)

    Klokkenburg, M.; Erne, B.H.; Mendelev, V.; Ivanov, A.O.

    2008-01-01

    Theories and simulations have demonstrated that field-induced dipolar chains affect the static magnetic properties of ferrofluids. Experimental verification, however, has been complicated by the high polydispersity of the available ferrofluids, and the morphology of the dipolar chains was left to th

  16. Improvisation and Meditation in the Academy: Parallel Ordeals, Insights, and Openings

    Science.gov (United States)

    Sarath, Edward

    2015-01-01

    This article examines parallel challenges and avenues for progress I have observed in my efforts to introduce improvisation in classical music studies, and meditation in music and overall academic settings. Though both processes were once central in their respective knowledge traditions--improvisation in earlier eras of European classical music,…

  17. English Class at the Improv: Using Improvisation to Teach Middle School Students Confidence, Community, and Content

    Science.gov (United States)

    Maples, Joellen

    2007-01-01

    In this article, the author describes a personal teaching experience that led her to incorporate improvisational drama into her English classroom. The author describes justifications for implementing drama into the classroom as well as the possible benefits gained by teachers and students. Also included are several improvisational dramatic…

  18. Development and Validation of a Rating Scale for Wind Jazz Improvisation Performance

    Science.gov (United States)

    Smith, Derek T.

    2009-01-01

    The purpose of this study was to construct and validate a rating scale for collegiate wind jazz improvisation performance. The 14-item Wind Jazz Improvisation Evaluation Scale (WJIES) was constructed and refined through a facet-rational approach to scale development. Five wind jazz students and one professional jazz educator were asked to record…

  19. An Approach to Improvisation Pedagogy in Post-Secondary Jazz Programmes Based on Negative Dialectics

    Science.gov (United States)

    Louth, Joseph Paul

    2012-01-01

    This article argues that an approach to jazz improvisation pedagogy based on negative dialectics may provide a viable solution to the threat of codification of the jazz language as a result of the academisation of improvisation studies at the post-secondary level. Some tentative means of incorporating such an approach into the design of university…

  20. Spontaneous Dancemaking with Beginning Improvisers: Foundational Practices in Presence, Stillness, and Problem Solving

    Science.gov (United States)

    Martin, Nina

    2017-01-01

    Many dance artists in their first encounters with improvisational dance making begin not only to learn how to compose spontaneously, but also to gain skills for coping with the uncertainties inherent in the form. This article suggests helpful dance scores for beginning students of physical improvisation and those who teach improvisational…

  1. Improvisation and Meditation in the Academy: Parallel Ordeals, Insights, and Openings

    Science.gov (United States)

    Sarath, Edward

    2015-01-01

    This article examines parallel challenges and avenues for progress I have observed in my efforts to introduce improvisation in classical music studies, and meditation in music and overall academic settings. Though both processes were once central in their respective knowledge traditions--improvisation in earlier eras of European classical music,…

  2. Development and Validation of a Rating Scale for Wind Jazz Improvisation Performance

    Science.gov (United States)

    Smith, Derek T.

    2009-01-01

    The purpose of this study was to construct and validate a rating scale for collegiate wind jazz improvisation performance. The 14-item Wind Jazz Improvisation Evaluation Scale (WJIES) was constructed and refined through a facet-rational approach to scale development. Five wind jazz students and one professional jazz educator were asked to record…

  3. Spontaneous Dancemaking with Beginning Improvisers: Foundational Practices in Presence, Stillness, and Problem Solving

    Science.gov (United States)

    Martin, Nina

    2017-01-01

    Many dance artists in their first encounters with improvisational dance making begin not only to learn how to compose spontaneously, but also to gain skills for coping with the uncertainties inherent in the form. This article suggests helpful dance scores for beginning students of physical improvisation and those who teach improvisational…

  4. A Classroom-Based Study of Small-Group Planned Improvisation with Fifth-Grade Children

    Science.gov (United States)

    Beegle, Amy C.

    2010-01-01

    The purpose of this study was to examine and describe children's music improvisations and the interactions that transpired within their four-person groups during regular weekly music classes as they planned and performed music improvisations in response to three different prompts: a poem, a painting, and a musical composition. Participants were…

  5. Teaching Improvisation and the Pedagogical History of the Jimmy Giuffre 3

    Science.gov (United States)

    Johnston, Peter

    2013-01-01

    Improvisation pedagogy has presented a challenge to music educators since jazz courses began being offered in North American universities in the 1950s, a development which has raised important pedagogical questions ranging from 'Can improvisation be taught?' to "Should it be taught?" Following on the increase in academic…

  6. An Approach to Improvisation Pedagogy in Post-Secondary Jazz Programmes Based on Negative Dialectics

    Science.gov (United States)

    Louth, Joseph Paul

    2012-01-01

    This article argues that an approach to jazz improvisation pedagogy based on negative dialectics may provide a viable solution to the threat of codification of the jazz language as a result of the academisation of improvisation studies at the post-secondary level. Some tentative means of incorporating such an approach into the design of university…

  7. Something in the Air: Journeys of Self-Actualization in Musical Improvisation

    Directory of Open Access Journals (Sweden)

    Heidi Ahonen

    2009-07-01

    Full Text Available The aim of this qualitative, abductive, and phenomenological inquiry was to develop categories based on participants' perceptions of their improvisation and listening experiences. As using improvised music in clinical music therapy is an important method, this study expanded the knowledge of and language needed to describe this very sensitive and insightful communication process. If there is something in the air—what is it and is it something significant? Research questions included: 1. What kind of process is experienced when one improvises with an unknown person in an unfamiliar musical style? 2. What is in the air during live interactive improvisation? 3. What are the links between processes of self-actualization and peak experiences introduced by Abraham Maslow (1968 and the experiences described by the participants regarding their live improvised/interactive musical processes? The data of this study consisted of two audio-taped improvisations, three interviews, and the written reflections of six participants who participated in interactive live improvisation sessions. Ferrara's method was adapted for the data collection and analysis. Research results are presented in the form of descriptive categories which give a clearer picture of what happens during the process of musical improvisation.

  8. Say Who You Are, Play Who You Are: Improvisation, Pedagogy, and Youth on the Margins

    Science.gov (United States)

    Willox, Ashlee Cunsolo; Heble, Ajay; Jackson, Rob; Walker, Melissa; Waterman, Ellen

    2011-01-01

    This paper presents a research that emerges from a set of community-based outreach activities associated with a large-scale, interdisciplinary project, Improvisation, Community, and Social Practice (ICASP), which focuses on the social and pedagogical implications of improvised musical practices. Working from the premise that musical improvisation…

  9. Moments of resonance in musical improvisation with persons with severe dementia

    DEFF Research Database (Denmark)

    Coomans, Anke

    that benefit from a non-verbal approach. The findings of the study provide insights in the role of musical improvisation for the occurrence of moments of resonance in music therapy with persons with severe dementia. The reader is led through the characteristics of musical improvisation and the specifics...

  10. Magnetic ordering and non-Fermi-liquid behavior in the multichannel Kondo-lattice model

    Science.gov (United States)

    Irkhin, Valentin Yu.

    2016-05-01

    Scaling equations for the Kondo lattice in the paramagnetic and magnetically ordered phases are derived to next-leading order with account of spin dynamics. The results are applied to describe various mechanisms of the non-Fermi-liquid (NFL) behavior in the multichannel Kondo-lattice model where a fixed point occurs in the weak-coupling region. The corresponding temperature dependences of electronic and magnetic properties are discussed. The model describes naturally formation of a magnetic state with soft boson mode and small moment value. An important role of Van Hove singularities in the magnon spectral function is demonstrated. The results are rather sensitive to the type of magnetic ordering and space dimensionality, the conditions for NFL behavior being more favorable in the antiferromagnetic and 2D cases.

  11. Scaling Behavior of the First Arrival Time of a Random-Walking Magnetic Domain

    Energy Technology Data Exchange (ETDEWEB)

    Im, M.-Y.; Lee, S.-H.; Kim, D.-H.; Fischer, P.; Shin, S.-C.

    2008-02-04

    We report a universal scaling behavior of the first arrival time of a traveling magnetic domain wall into a finite space-time observation window of a magneto-optical microscope enabling direct visualization of a Barkhausen avalanche in real time. The first arrival time of the traveling magnetic domain wall exhibits a nontrivial fluctuation and its statistical distribution is described by universal power-law scaling with scaling exponents of 1.34 {+-} 0.07 for CoCr and CoCrPt films, despite their quite different domain evolution patterns. Numerical simulation of the first arrival time with an assumption that the magnetic domain wall traveled as a random walker well matches our experimentally observed scaling behavior, providing an experimental support for the random-walking model of traveling magnetic domain walls.

  12. Surface magnetism Correlation of structural, electronic and chemical properties with magnetic behavior

    CERN Document Server

    Getzlaff, Mathias

    2010-01-01

    This volume reviews on selected aspects related to surface magnetism, a field of extraordinary interest during the last decade. The special emphasis is set to the correlation of structural, electronic and magnetic properties in rare earth metal systems and ferromagnetic transition metals. This is made possible by the combination of electron emission techniques (spin polarized photoelectron spectroscopy, magnetic dichroism in photoemission and spin polarized metastable deexcitation spectroscopy) and local probes with high lateral resolution down to the atomic scale (spin polarized scanning tunneling microscopy / spectroscopy).

  13. Magnetic effects on dielectric and polarization behavior of multiferroic heterostructures

    Science.gov (United States)

    Dussan, Sandra; Kumar, Ashok; Scott, J. F.; Katiyar, Ram S.

    2010-02-01

    PbZr0.52Ti0.48O3/La0.67Sr0.33MnO3(PZT/LSMO) bilayer with surface roughness ˜1.8 nm thin films have been grown by pulsed laser deposition on LaAlO3(LAO) substrates. High remnant polarization (30-54 μC/cm2), dielectric constant (400-1700), and well saturated magnetization were observed depending upon the deposition temperature of the ferromagnetic layer and applied frequencies. Giant frequency-dependent change in dielectric constant and loss were observed above the ferromagnetic-paramagnetic temperature. The frequency dependent dielectric anomalies are attributed to the change in metallic and magnetic nature of LSMO and also the interfacial effect across the bilayer; an enhanced magnetoelectric interaction may be due to the Parish-Littlewood mechanism of inhomogeneity near the metal-dielectric interface.

  14. Magnetization behavior of nanocrystalline systems combining ferromagnetic and antiferromagnetic phases

    Energy Technology Data Exchange (ETDEWEB)

    Loeffler, J.; Wagner, W.; Svygenhoven, H. van [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Meier, J.; Doudin, B.; Ansermet, J.P. [Ecole Polytechnique Federale, Lausanne (Switzerland)

    1997-09-01

    The magnetic properties of nanostructured materials on the basis of Fe and Ni have been investigated with a SQUID magnetometer, complementary to the small-angle neutron scattering study reported in the same volume. Measurements of the coercive field in a temperature range from 5 to 300 K confirm the validity of the random anisotropy model for our nanostructured systems. Furthermore, we obtain information about the presence and distribution of the antiferromagnetic oxides, joining the ferromagnetic grains. (author) 2 figs., 3 refs.

  15. MAGNETIC FIELD GRADIENT EFFECTS ON ION FLUX BEHAVIORS IN ECR PLASMA SOURCES

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The available electron cyclotron resonance plasma source has been simulated in two-dimensional configuration space (z, r) and three-dimensional velocity space (Vz, Vr Vθ). The simulation is focused on the magnetic field gradient effects on ion flux behaviors in electron cyclotron resonance plasma sources. The simulation results show that, when the magnetic field gradients increase, electron temperature, plasma density, ionization rate, and ion flux in Zdirection would decrease, while ion energy and plasma potential would increase.

  16. Single-molecule magnet behavior with a single metal center enhanced through peripheral ligand modifications.

    Science.gov (United States)

    Jurca, Titel; Farghal, Ahmed; Lin, Po-Heng; Korobkov, Ilia; Murugesu, Muralee; Richeson, Darrin S

    2011-10-12

    Bis(imino)pyridine pincer ligands in conjunction with two isothiocyanate ligands have been used to prepare two mononuclear Co(II) complexes. Both complexes have a distorted square-pyramidal geometry with the Co(II) centers lying above the basal plane. This leads to significant spin-orbit coupling for the d(7) Co(II) ions and consequently to slow relaxation of the magnetization that is characteristic of Single-Molecule Magnet (SMM) behavior.

  17. Strong static magnetic fields elicit swimming behaviors consistent with direct vestibular stimulation in adult zebrafish.

    Directory of Open Access Journals (Sweden)

    Bryan K Ward

    Full Text Available Zebrafish (Danio rerio offer advantages as model animals for studies of inner ear development, genetics and ototoxicity. However, traditional assessment of vestibular function in this species using the vestibulo-ocular reflex requires agar-immobilization of individual fish and specialized video, which are difficult and labor-intensive. We report that using a static magnetic field to directly stimulate the zebrafish labyrinth results in an efficient, quantitative behavioral assay in free-swimming fish. We recently observed that humans have sustained nystagmus in high strength magnetic fields, and we attributed this observation to magnetohydrodynamic forces acting on the labyrinths. Here, fish were individually introduced into the center of a vertical 11.7T magnetic field bore for 2-minute intervals, and their movements were tracked. To assess for heading preference relative to a magnetic field, fish were also placed in a horizontally oriented 4.7T magnet in infrared (IR light. A sub-population was tested again in the magnet after gentamicin bath to ablate lateral line hair cell function. Free-swimming adult zebrafish exhibited markedly altered swimming behavior while in strong static magnetic fields, independent of vision or lateral line function. Two-thirds of fish showed increased swimming velocity or consistent looping/rolling behavior throughout exposure to a strong, vertically oriented magnetic field. Fish also demonstrated altered swimming behavior in a strong horizontally oriented field, demonstrating in most cases preferred swimming direction with respect to the field. These findings could be adapted for 'high-throughput' investigations of the effects of environmental manipulations as well as for changes that occur during development on vestibular function in zebrafish.

  18. Abnormal magnetic behavior in DMS Zn1-xMnxO nanowires

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Zn1-xMnxO nanowires were synthesized through chemical vapor deposition of pure Zn and MnCl2 power mixtures on silicon substrates. The morphology, structure and composition were measured by SEM, TEM, EDX and XRD. Magnetic properties were measured by SQUID. The results show that the nanowires exhibit clear ferromagnetic behavior at low temperature. An abnormal peak is observed in the M-T curve at 55 K in a magnetic field of 500 Oe.

  19. Magnetic behavior of the giant Heisenberg molecular magnet Mo_72Fe_30: Classical theory and experiment

    Science.gov (United States)

    Luban, Marshall; Modler, Robert; Axenovich, Maria; Canfield, Paul; Bud'Ko, Sergey; Schröder, Christian; Schnack, Jürgen; Müller, Achim; Kögerler, Paul; Harrison, Neil

    2001-03-01

    The Keplerate species Mo_72Fe_30 containing 30 high-spin Fe^3+ ions, is by far the largest paramagnetic molecule synthesized to date, and it serves as an effective building block and prototype for a new class of diverse molybdenum-oxygen based compounds. These substances are of importance for identifying the most pertinent criteria for the passage from microscopic to macroscopic magnetism, and for their potential as molecular-based electronic and magnetic devices. We report excellent agreement, from room temperature down to 0.1 K, and for magnetic fields up to 60 Tesla between our theoretical results based on the classical Heisenberg model and our measurements of its magnetic properties.

  20. Differences in structure and magnetic behavior of Mn-AlN films due to substrate material

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Takanobu; Nakatani, Ryoichi [Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University (Japan); Endo, Yasushi [Depertment of Electrical and Communication Engineering, Graduate School of Engineering, Tohoku University (Japan); Kirino, Fumiyoshi [Conservation of Cultural Property, Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music (Japan)], E-mail: takanobu.sato@mat.eng.osaka-u.ac.jp

    2009-05-01

    The structure and magnetic behavior of Mn-AlN (Al{sub 1-x}Mn{sub x}N, x = 0.03, 0.04) films deposited on thermally oxidized Si (001) substrates and sapphire (0001) substrates were studied. Mn-AlN films deposited on each substrate had a wuertzite-type AlN phase with a preferentially oriented c-axis. Mn-AlN films that were deposited on Si (001) substrate exhibited paramagnetic behavior. In addition to paramagnetic behavior, weak ferromagnetic behavior with curie temperatures higher than room temperature were observed for Mn-AlN films deposited on sapphire (0001) substrates.

  1. Influence of axial self-magnetic field component on arcing behavior of spiral-shaped contacts

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Dingyu; Xiu, Shixin, E-mail: xsx@mail.xjtu.edu.cn; Wang, Yi; Liu, Gang [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Yali; Bi, Dongli [Shaanxi Baoguang Vacuum Electric Device Co., Ltd., 53 Xibao Road, Baoji 721006 (China)

    2015-10-15

    The transverse magnetic field (TMF) contact design is commonly used in vacuum interrupters. When arcing occurs between the TMF contacts, the contact structure can create a self-induced magnetic field that drives the arc to move and rotate on the contact, and thus local overheating and severe erosion can be avoided. However, TMF contacts could also create an axial self-magnetic component, and the influence of this component on the arc behavior has not been considered to date. In this paper, five different types of Cu-Cr spiral-shaped TMF contacts with three different structures are investigated in a demountable vacuum chamber that contains a high-speed charge-coupled device video camera. It was found that the contact structure greatly influenced the arc behavior, especially in terms of arc rotation and the effective contact area, while contacts with the same slot structure but different diameters showed similar arc behavior and arc motion. The magnetic field distribution and the Lorentz force of each of the three different contact structures are simulated, and the axial self-magnetic field was first taken into consideration for investigation of the TMF contact design. It was found that contact designs that have higher axial self-magnetic field components tend to have arc columns with larger diameters and show poorer arc motion and rotation performance in the experiments.

  2. Electrochemical Corrosion Behavior of Nd-Fe-B Sintered Magnets in Different Acid Solutions

    Institute of Scientific and Technical Information of China (English)

    Zheng Jingwu; Jiang Liqiang; Chen Qiaoling

    2006-01-01

    Electrochemical corrosion behavior of Nd-Fe-B sintered magnets in nitric acid, hydrochloric acid, sulfuric acid, phosphate acid and in oxalic acid was studied.Potentiodynamic polarization curves and immersion time dependence of corrosion rates of Nd-Fe-B sintered magnets in different acid solutions were tested.Microstructures of corroded Nd-Fe-B sintered magnets were investigated by means of SEM and AFM.The results indicate that in strong acid solutions of similar hydrogen ion concentration, the corrosion current increases in the order of HCl>H2SO4>HNO3 solution and Nd-Fe-B sintered magnets are passivated in phosphate acid and oxalic acid.Within 25 min, the corrosion rates of Nd-Fe-B sintered magnets in H2SO4 and H3PO4 solutions show a declining trend with immersion time, while in HNO3 and HCl solutions the corrosion rates are rising.And in H2C2O4 solution, weight of the magnets increases.The brim of Nd-Fe-B sintered magnets is corroded rather seriously and the size of the magnets changed greatly in nitric acid.The surfaces of the corroded magnets in the above mentioned acid solutions are all coarse.

  3. Alternating magnetic field heat behaviors of PVDF fibrous mats filled with iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Jinu Kim

    2016-05-01

    Full Text Available To study the magnetic heat behaviors, iron oxide nanoparticles (IONPs and the polyvinylidene fluoride (PVDF fibrous mats filled with IONPs were prepared by using coprecipitaion method and the electrospinning technique. The synthesized IONPs exhibited a magnetization of about 72 emu/g with average diameter of about 10 nm. The magnetizations of PVDF fibrous mats filled with IONPs showed 2.6 emu/g, 5.5 emu/g and 9.9 emu/g for 5 wt.%, 10 wt.% and 20 wt.% IONPs concentration, respectively. The heat of the magnetic fibrous mats were measured under various alternating magnetic fields (90, 128, and 167 Oe, frequencies (190, 250 and 355 kHz. The maximum saturated temperature showed up to 62 °C for 20 wt.% IONPs filled in PVDF fibrous mat under 167 Oe and 355 kHz.

  4. Alternating magnetic field heat behaviors of PVDF fibrous mats filled with iron oxide nanoparticles

    Science.gov (United States)

    Kim, Jinu; Choi, Jung-Su; Yang, Heejae; Ko, Frank K.; Kim, Ki Hyeon

    2016-05-01

    To study the magnetic heat behaviors, iron oxide nanoparticles (IONPs) and the polyvinylidene fluoride (PVDF) fibrous mats filled with IONPs were prepared by using coprecipitaion method and the electrospinning technique. The synthesized IONPs exhibited a magnetization of about 72 emu/g with average diameter of about 10 nm. The magnetizations of PVDF fibrous mats filled with IONPs showed 2.6 emu/g, 5.5 emu/g and 9.9 emu/g for 5 wt.%, 10 wt.% and 20 wt.% IONPs concentration, respectively. The heat of the magnetic fibrous mats were measured under various alternating magnetic fields (90, 128, and 167 Oe), frequencies (190, 250 and 355 kHz). The maximum saturated temperature showed up to 62 °C for 20 wt.% IONPs filled in PVDF fibrous mat under 167 Oe and 355 kHz.

  5. Effect of loading speed on the stress-induced magnetic behavior of ferromagnetic steel

    Science.gov (United States)

    Bao, Sheng; Gu, Yibin; Fu, Meili; Zhang, Da; Hu, Shengnan

    2017-02-01

    The primary goal of this research is to investigate the effect of loading speed on the stress-induced magnetic behavior of a ferromagnetic steel. Uniaxial tension tests on Q235 steel were carried out with various stress levels under different loading speeds. The variation of the magnetic signals surrounding the tested specimen was detected by a fluxgate magnetometer. The results indicated that the magnetic signal variations depended not only on the tensile load level but on the loading speed during the test. The magnetic field amplitude seemed to decrease gradually with the increase in loading speed at the same tensile load level. Furthermore, the evolution of the magnetic reversals is also related to the loading speed. Accordingly, the loading speed should be considered as one of the influencing variables in the Jies-Atherton model theory of the magnetomechanical effect.

  6. Interprofessional communication and teambuilding using applied improvisational exercises.

    Science.gov (United States)

    Campbell, Candace

    2014-01-01

    According to The Joint Commission (TJC), the most frequently cited root cause of sentinel events is ineffective communication or miscommunication (TJC, 2002, 2012). The need to improve communication among health care professionals is a high priority because of the serious consequences of poor communication for everyone involved, on both personal and corporate levels. Applied improvisational exercises (AlEs) comprise a strategy for enhancing interprofessional communication (IPC). This article asks: What are the challenges inherent in IPC and teambuilding in the health care setting, and how can AIE help bridge the communication gap?

  7. Effects of hypothetical improvised nuclear detonation on the electrical infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, Christopher L.; Eubank, Stephen; Evrenosoglu, C. Yaman; Marathe, Achla; Marathe, Madhav V.; Phadke, Arun; Thorp, James; Vullikanti, Anil [Virginia Tech, Blacksburg, VA (United States). Network Dynamics and Simulation Science Lab.

    2013-07-01

    We study the impacts of a hypothetical improvised nuclear detonation (IND) on the electrical infrastructure and its cascading effects on other urban inter-dependent infrastructures of a major metropolitan area in the US. We synthesize open source information, expert knowledge, commercial software and Google Earth data to derive a realistic electrical transmission and distribution network spanning the region. A dynamic analysis of the geo-located grid is carried out to determine the cause of malfunction of components, and their short-term and long-term effect on the stability of the grid. Finally a detailed estimate of the cost of damage to the major components of the infrastructure is provided.

  8. Improvised explosive devices and the oral and maxillofacial surgeon.

    Science.gov (United States)

    Goksel, Tamer

    2005-08-01

    Improvised explosive devices have created a new class of casualties that presents a unique surgical challenge for oral and maxillofacial surgeons. The injury pattern and severity are different from those seen in conventional trauma patients. Because of battlefield circumstances, patients are sometimes delayed significantly in their transport to a trauma center, and they frequently arrive at a trauma center with hypotension, hypothermia, and acidosis. Definitive care is delayed while the hemodynamic status and life-threatening injuries are stabilized. Hospital triage protocols must be well established in advance to prepare a timely response to the mass casualty event. Proper resource use is an ever-evolving challenge for hospital staff during these times.

  9. Mechanical behavior of the mirror fusion test Facility superconducting magnet coils

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, J.A.

    1980-01-01

    The mechanical response to winding and electromagnetic loads of the Mirror Fusion Test Facility (MFTF) superconducting coil pack is presented. The 375-ton (3300 N) MFTF Yin-Yang magnet, presently the world's largest superconducting magnet, is scheduled for acceptance cold-testing in May of 1981. The assembly is made up of two identical coils which together contain over 15 miles (24 km) of superconductor wound in 58 consecutive layers of 24 turns each. Topics associated with mechanical behavior include physical properties of the coil pack and its components, winding pre-load effects, finite element analysis, magnetic load redistribution, and the design impact of predicted conductor motion.

  10. Magnetic hysteresis, compensation behaviors, and phase diagrams of bilayer honeycomb lattices

    Institute of Scientific and Technical Information of China (English)

    Ersin Kantar

    2015-01-01

    Magnetic behaviors of the Ising system with bilayer honeycomb lattice (BHL) structure are studied by using the effective-field theory (EFT) with correlations. The effects of the interaction parameters on the magnetic properties of the system such as the hysteresis and compensation behaviors as well as phase diagrams are investigated. Moreover, when the hysteresis behaviors of the system are examined, single and double hysteresis loops are observed for various values of the interaction parameters. We obtain the L-, Q-, P-, and S-type compensation behaviors in the system. We also observe that the phase diagrams only exhibit the second-order phase transition. Hence, the system does not show the tricritical point (TCP).

  11. Magnetic Behavior of a Mott-Insulator YVO3

    Science.gov (United States)

    Kawano, Hazuki; Yoshizawa, Hideki; Ueda, Yutaka

    1994-08-01

    As one of the members of the ABO3-type pseudoperovskite oxide family, Y1-xCaxVO3 exhibits an insulator-metal transition upon a change in the dopant calcium ion concentration x. We have reinvestigated the magnetic structure of the parent compound YVO3 with use of the neutron scattering technique. YVO3 orders at T N1=118 K with the so-called C-type antiferromagnetic structure, but changes to the G-type antiferromagnetic structure at T N2˜77 K through a first order transition with lattice distortion. These spin structures differ from those of an early study by Zubkov et al. (Sov. Phys.-JETP 39 (1974) 896). The static moment which contributes to the magnetic long range order is extrapolated to be less than 1.6 µ B at T=0 K. This value of the static moment is more than 20% smaller than 2.0 µ B expected for a localized spin system with S=1, indicating the existence of spin fluctuations in a Mott insulator YVO3.

  12. Magnetic behavior of Mg-Al-Zn-Fe mixed oxides from precursors layered double hydroxide

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, M.I., E-mail: marcosivanoliva@gmail.com [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, M. Allende y H. de la Torre Ciudad Universitaria, 5000 Cordoba (Argentina); IFFAM AF (CONICET - FaMAF UNC), M. Allende y H. de la Torre Ciudad Universitaria, 5000 Cordoba (Argentina); Heredia, A. [CITeQ - Facultad R. Cordoba, Universidad Tecnologica Nacional Maestro Lopez esq. Cruz Roja Argentina, CP 5016 Cordoba (Argentina); Zandalazini, C.I. [Centro Laser de Ciencias Moleculares. INFIQC-FCQ-Grupo de Ciencia de Materiales-FaMAF-Universidad Nacional de Cordoba, Ciudad Universitaria, CP5000 Cordoba, Argentina CONICET (Argentina); Crivello, M. [CITeQ - Facultad R. Cordoba, Universidad Tecnologica Nacional Maestro Lopez esq. Cruz Roja Argentina, CP 5016 Cordoba (Argentina); Corchero, E. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, M. Allende y H. de la Torre Ciudad Universitaria, 5000 Cordoba (Argentina)

    2012-08-15

    Mixed oxides of Mg-Al-Zn-Fe were obtained by calcination of layered double hydroxides (LDH) prepared by coprecipitation reaction with hydrothermal treatment. The structural characterization of precursors and oxides was carried out by X rays diffraction, showing increases of ZnO phase with the increase of the zinc content. Magnetic behavior was studied by vibrating sample magnetometer (VSM) and by a superconducting quantum interference device (SQUID) showing both paramagnetic and super paramagnetic behavior depending on both particles size and composition.

  13. Magnetic Behavior of Surface Nanostructured 50-nm Nickel Thin Films

    Directory of Open Access Journals (Sweden)

    Kumar Prashant

    2010-01-01

    Full Text Available Abstract Thermally evaporated 50-nm nickel thin films coated on borosilicate glass substrates were nanostructured by excimer laser (0.5 J/cm2, single shot, DC electric field (up to 2 kV/cm and trench-template assisted technique. Nanoparticle arrays (anisotropic growth features have been observed to form in the direction of electric field for DC electric field treatment case and ruptured thin film (isotropic growth features growth for excimer laser treatment case. For trench-template assisted technique; nanowires (70–150 nm diameters have grown along the length of trench template. Coercive field and saturation magnetization are observed to be strongly dependent on nanostructuring techniques.

  14. Behavior of metals Induced by magnetic pulse loading

    Directory of Open Access Journals (Sweden)

    Svetlana Atroshenko

    2015-01-01

    Full Text Available The investigation of copper and aluminum ring samples was carried out using magnetic pulse loading. Two modifications of the magnetic pulse technique were used. They were based on a GKVI-300 high-voltage narrow-pulse generator Morozov et al. (2011 [1]. It is possible using these two approaches to decrease the period of the harmonic load up to 100 ns. The study of fracture surfaces of aluminum and copper samples after the test was carried out on an optical microscope Axio-Observer-Z1-M in a dark field, and study of the cross sections structure – in the bright field or C-DIC. The structure has been studied in cross sections after appropriate etching. Grain size and the number of pores on the surface of cross sections were determined after etching. Microhardness was measured on a PMT-3 device with a load of 20 g. The optical micrographs of aluminum demonstrate that the long pulse causes almost fully ductile fracture. In the case of the short pulse, the number of fibers decreases: the fracture surface exhibits the signs of both ductile cup fracture and brittle crystalline fracture with cracks, which are sometimes rather deep. In addition, the short pulse results in twinning, which seems surprising for aluminum featuring a high stacking fault energy. It is seen that under short loading dynamic recrystallization occurs. As for copper samples before loading they were in the form of single crystal and after loading their structure due to dynamic recrystallization consists of small grain. The specimen with notch has more developed dynamic recrystallization shear bands.

  15. Creativity as openness: improvising health and care 'situations'.

    Science.gov (United States)

    Oliver, James

    2009-12-01

    Creativity has become an oft-used word in UK public policy, but perhaps it is also under-imagined. This paper contends that there is an instrumental tendency to narrowly frame creativity as innovation, implying a reproducible product, instead of more openly as improvisation, a situational, embodied and temporal process. This is not a simple dichotomy (innovation and improvisation, product and process, can be mutually informing concepts), nor is it specifically a question of definition; rather, it relates to an ontological orientation, and related to that are issues of epistemological implications. In particular the paper is concerned with the value of the arts in public policy, as situated in the social, and therefore human, spaces of health and care; and more generally the arts in society. The paper brings together a broad discussion from across disciplines, not in an interdisciplinary attempt to solve a problem, or to be reductive in the analysis, but to begin to approach a reorienting of understandings of creativity and the human value and foundation of the arts in society.

  16. Perpendicular Magnetization Behavior of Low- Temperature Ordered FePt Films with Insertion of Ag Nanolayers

    Directory of Open Access Journals (Sweden)

    Da-Hua Wei

    2016-03-01

    Full Text Available FePt-Ag nanocomposite films with large perpendicular magnetic anisotropy have been fabricated by alternate-atomic-layer electron beam evaporation onto MgO(100 substrates at the low temperature of 300 °C. Their magnetization behavior and microstructure have been studied. The surface topography was observed and varied from continuous to nanogranular microstructures with insertion of Ag nanolayers into Fe/Pt bilayer films. The measurement of angular-dependent coercivity showed a tendency of the domain-wall motion as a typical peak behavior shift toward more like a coherent Stoner-Wohlfarth rotation type with the insertion of Ag nanolayers into the FePt films. On the other hand, the inter-grain interaction was determined from a Kelly-Henkel plot. The FePt film without insertion of Ag nanolayers has a positive δM, indicating strong exchange coupling between neighboring grains, whereas the FePt film with insertion of Ag nanolayers has a negative δM, indicating that inter-grain exchange coupling is weaker, thus leading to the presence of dipole interaction in the FePt–Ag nanogranular films. The magnetic characteristic measurements confirmed that the perpendicular magnetization reversal behavior and related surface morphology of low-temperature-ordered FePt(001 nanogranular films can be systematically controlled by the insertion of Ag nanolayers into the FePt system for next generation magnetic storage medium applications.

  17. Teaching Improvisation through Processes. Applications in Music Education and Implications for General Education.

    Science.gov (United States)

    Biasutti, Michele

    2017-01-01

    Improvisation is an articulated multidimensional activity based on an extemporaneous creative performance. Practicing improvisation, participants expand sophisticated skills such as sensory and perceptual encoding, memory storage and recall, motor control, and performance monitoring. Improvisation abilities have been developed following several methodologies mainly with a product-oriented perspective. A model framed under the socio-cultural theory of learning for designing didactic activities on processes instead of outcomes is presented in the current paper. The challenge is to overcome the mere instructional dimension of some practices of teaching improvisation by designing activities that stimulate self-regulated learning strategies in the students. In the article the present thesis is declined in three ways, concerning the following three possible areas of application: (1) high-level musical learning, (2) musical pedagogy with children, (3) general pedagogy. The applications in the music field focusing mainly on an expert's use of improvisation are discussed. The last section considers how these ideas should transcend music studies, presenting the benefits and the implications of improvisation activities for general learning. Moreover, the application of music education to the following cognitive processes are discussed: anticipation, use of repertoire, emotive communication, feedback and flow. These characteristics could be used to outline a pedagogical method for teaching music improvisation based on the development of reflection, reasoning, and meta-cognition.

  18. Provider experiences with improvised uterine balloon tamponade for the management of uncontrolled postpartum hemorrhage in Kenya.

    Science.gov (United States)

    Natarajan, Abirami; Alaska Pendleton, Anna; Nelson, Brett D; Ahn, Roy; Oguttu, Monica; Dulo, Lidu; Eckardt, Melody J; Burke, Thomas F

    2016-11-01

    To understand healthcare providers' experiences with improvised uterine balloon tamponade (UBT) for the management of uncontrolled postpartum hemorrhage (PPH). In a qualitative descriptive study, in-depth semi-structured interviews were conducted between November 2014 and June 2015 among Kenyan healthcare providers who had previous experience with improvising a UBT device. Interviews were conducted, audio-recorded, and transcribed. Overall, 29 healthcare providers (14 nurse-midwifes, 7 medical officers, 7 obstetricians, and 1 clinical officer) were interviewed. Providers perceived improvised UBT as valuable for managing uncontrolled PPH. Reported benefits included effectiveness in arresting hemorrhage and averting hysterectomy, and ease of use by providers of all levels of training. Providers used various materials to construct an improvised UBT. Challenges to improvising UBT-e.g. searching for materials during an emergency, procuring male condoms, and inserting fluid via a small syringe-were reported to lead to delays in care. Providers described their introduction to improvised UBT through both formal and informal sources. There was universal enthusiasm for widespread standardized training. Improvised UBT seems to be a valuable second-line treatment for uncontrolled PPH that can be used by providers of all levels. UBT might be optimized by integrating a standard package across the health system. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  19. Teaching Improvisation through Processes. Applications in Music Education and Implications for General Education

    Directory of Open Access Journals (Sweden)

    Michele Biasutti

    2017-06-01

    Full Text Available Improvisation is an articulated multidimensional activity based on an extemporaneous creative performance. Practicing improvisation, participants expand sophisticated skills such as sensory and perceptual encoding, memory storage and recall, motor control, and performance monitoring. Improvisation abilities have been developed following several methodologies mainly with a product-oriented perspective. A model framed under the socio-cultural theory of learning for designing didactic activities on processes instead of outcomes is presented in the current paper. The challenge is to overcome the mere instructional dimension of some practices of teaching improvisation by designing activities that stimulate self-regulated learning strategies in the students. In the article the present thesis is declined in three ways, concerning the following three possible areas of application: (1 high-level musical learning, (2 musical pedagogy with children, (3 general pedagogy. The applications in the music field focusing mainly on an expert's use of improvisation are discussed. The last section considers how these ideas should transcend music studies, presenting the benefits and the implications of improvisation activities for general learning. Moreover, the application of music education to the following cognitive processes are discussed: anticipation, use of repertoire, emotive communication, feedback and flow. These characteristics could be used to outline a pedagogical method for teaching music improvisation based on the development of reflection, reasoning, and meta-cognition.

  20. Statistical Behavior of Formation Process of Magnetic Vortex State in Ni80Fe20 Nanodisks

    Energy Technology Data Exchange (ETDEWEB)

    Im, Mi-Young; Fischer, Peter; Keisuke, Yamada; Kasai, Shinya

    2011-01-14

    Magnetic vortices in magnetic nanodots, which are characterized by an in-plane (chirality) and an out-of-plane (polarity) magnetizations, have been intensively attracted because of their high potential for technological application to data storage and memory scheme as well as their scientific interest for an understanding of fundamental physics in magnetic nanostructures. Complete understanding of the formation process of vortex state in magnetic vortex systems is very significant issue to achieve storage and memory technologies using magnetic vortices and understand intrinsic physical properties in magnetic nanostructures. In our work, we have statistically investigated the formation process of vortex state in permalloy (Py, Ni{sub 80}Fe{sub 20}) nanodisks through the direct observation of vortex structure utilizing a magnetic transmission soft X-ray microscopy (MTXM) with a high spatial resolution down to 20 nm. Magnetic imaging in Py nanodots was performed at the Fe L{sub 3} (707 eV) absorption edge. Figure 1 shows in-plane and out-of-plane magnetic components observed in 40 nm thick nanodot arrays with different dot radius of r = 500 and 400 nm, respectively. Vortex chirality, either clockwise (CW) or counter-clockwise (CCW), and polarity, either up or down, are clearly visible in both arrays. To investigate the statistical behavior in formation process of the vortex state, the observation of vortex structure at a remanant state after saturation of nanodots by an external magnetic field of 1 kOe has been repeatedly performed over 100 times for each array. The typical MTXM images of vortex chirality taken in two successive measurements together with their overlapped images in nanodot arrays of r = 500 and 400 nm are displayed in Fig. 2. Within the statistical measurement, the formation process of chirality of either CW or CCW is quite stochastic in each nanodot. Similar behavior is also witnessed in the formation of vortex polarity observed in consecutive

  1. Evidence for single-chain magnet behavior in a Mn(III)-Ni(II) chain designed with high spin magnetic units: a route to high temperature metastable magnets.

    Science.gov (United States)

    Clérac, Rodolphe; Miyasaka, Hitoshi; Yamashita, Masahiro; Coulon, Claude

    2002-10-30

    We herein present the synthesis, crystal structure, and magnetic properties of a new heterometallic chain of MnIII and NiII ions, [Mn2(saltmen)2Ni(pao)2(py)2](ClO4)2 (1) (saltmen2- = N,N'-(1,1,2,2-tetramethylethylene) bis(salicylideneiminate) and pao- = pyridine-2-aldoximate). The crystal structure of 1 was investigated by X-ray crystallographic analysis: compound 1 crystallized in monoclinic, space group C2/c (No. 15) with a = 21.140(3) A, b = 15.975(1) A, c = 18.6212(4) A, beta = 98.0586(4) degrees , V = 6226.5(7) A3, and Z = 4. This compound consists of two fragments, the out-of-plane dimer [Mn2(saltmen)2]2+ as a coordination acceptor building block and the neutral mononuclear unit [Ni(pao)2(py)2] as a coordination donor building block, forming an alternating chain having the repeating unit [-Mn-(O)2-Mn-ON-Ni-NO-]n. In the crystal structure, each chain is well separated with a minimum intermetallic distance between Mn and Ni ions of 10.39 A and with the absence of interchain pi overlaps between organic ligands. These features ensure a good magnetic isolation of the chains. The dc and ac magnetic measurements were performed on both the polycrystalline sample and the aligned single crystals of 1. Above 30 K, the magnetic susceptibility of this one-dimensional compound was successfully described in a mean field approximation as an assembly of trimers (Mn...Ni...Mn) with a NiII...MnIII antiferromagnetic interaction (J = -21 K) connected through a ferromagnetic MnIII...MnIII interaction (J'). However, the mean field theory fails to describe the magnetic behavior below 30 K emphasizing the one-dimensional magnetic character of the title compound. Between 5 and 15 K, the susceptibility in the chain direction was fitted to a one-dimensional Ising model leading to the same value of J'. Hysteresis loops are observed below 3.5 K, indicating a magnet-type behavior. In the same range of temperature, combined ac and dc measurements show a slow relaxation of the magnetization

  2. Hydrogenations and electric field induced magnetic behaviors in armchair silicene nanoribbons

    Science.gov (United States)

    Zhang, Dan; Long, Mengqiu; Xie, Fang; Ouyang, Jun; Xu, Hui; Gao, Yongli

    2016-01-01

    Using the first-principles calculations, we investigate the geometric, electronic and magnetic properties of armchair silicene nanoribbons with different edge hydrogenations. Our results show that the interesting magnetic behaviors such as the bipolar magnetic semiconductor can be found. Moreover, the addition of the transverse electric field can modulate the bipolar magnetic semiconductor to half-metal or spin-splitting metal. And the spin-up electrons are localized at one edge, the spin-down holes localized at the opposite edge under the external electric field. These results may present a new avenue for band engineering of silicene nanoribbons and benefit the design of silicon-based nano-spin-devices in nanoelectronics. PMID:27026136

  3. On the spatio-temporal behavior of magnetohydrodynamic turbulence in a magnetized plasma

    CERN Document Server

    Lugones, R; Mininni, P D; Wan, M; Matthaeus, W H

    2016-01-01

    Using direct numerical simulations of three-dimensional magnetohydrodynamic (MHD) turbulence the spatio-temporal behavior of magnetic field fluctuations is analyzed. Cases with relatively small, medium and large values of a mean background magnetic field are considered. The (wavenumber) scale dependent time correlation function is directly computed for different simulations, varying the mean magnetic field value. From this correlation function the time decorrelation is computed and compared with different theoretical times, namely, the local non-linear time, the random sweeping time, and the Alfv\\'enic time, the latter being a wave effect. It is observed that time decorrelations are dominated by sweeping effects, and only at large values of the mean magnetic field and for wave vectors mainly aligned with this field time decorrelations are controlled by Alfv\\'enic effects.

  4. Motion behavior of non-metallic particles under high frequency magnetic field

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhong-tao; GUO Qing-tao; YU Feng-yun; LI Jie; ZHANG Jian; LI Ting-ju

    2009-01-01

    Non-metallic particles, especially alumina, are the main inclusions in aluminum and its alloys. Numerical simulation and the corresponding experiments were carried out to study the motion behavior of alumina particles in commercial pure aluminum under high frequency magnetic field. At the meantime, multi-pipe experiment was also done to discuss the prospect of continuous elimination of non-metallic particles under high frequency magnetic field. It is shown that: 1) results of numerical simulation are in good agreement with the experimental results, which certificates the rationality of the simulation model; 2) when the intensity of high frequency magnetic field is 0.06 T, the 30 μm alumina particles in melt inner could migrate to the edge and be removed within 2 s; 3) multi-pipe elimination of alumina particles under high frequency magnetic field is also effective and has a good prospect in industrial application.

  5. Magnetic behavior in LiNbO{sub 3} nanocrystallites caused by oxygen vacancies

    Energy Technology Data Exchange (ETDEWEB)

    Díaz-Moreno, C.A. [Centro de Investigación en Materiales Avanzados S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Apdo. Postal 31109, México (Mexico); Farías-Mancilla, R. [Instituto de Ingeniería y Tecnología, Departamento de Física y Matemáticas, Ave. del Charro #450, Cd. Juarez C.P., 32310 Chihuahua (Mexico); Matutes-Aquino, J.A. [Centro de Investigación en Materiales Avanzados S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Apdo. Postal 31109, México (Mexico); Elizalde-Galindo, J. [Instituto de Ingeniería y Tecnología, Departamento de Física y Matemáticas, Ave. del Charro #450, Cd. Juarez C.P., 32310 Chihuahua (Mexico); Espinosa-Magaña, F.; González-Hernández, J. [Centro de Investigación en Materiales Avanzados S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Apdo. Postal 31109, México (Mexico); Hurtado-Macías, A., E-mail: abel.hurtado@cimav.edu.mx [Centro de Investigación en Materiales Avanzados S.C., Laboratorio Nacional de Nanotecnología, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Apdo. Postal 31109, México (Mexico)

    2014-04-01

    Ferromagnetism is observed in LiNiO{sub 3} nanocrystals exposed to a reducing atmosphere intended to create oxygen vacancies. The existence of vacancies is confirmed by measuring the oxygen depletion across the selected nanoparticles by TEM. The magnetism shows no temperature dependence in the range of 4–300 K. The density functional theory was used to perform spin polarized electronic structure calculations for LiNiO{sub 3} with and without oxygen vacancies. The calculated magnetic data qualitatively support the observed magnetic behavior. - Highlights: • Oxygen vacancies were formed at the surface of LiNiO{sub 3} nanocrystals by a temperature programmed reduction process. • The observed ferromagnetism in LiNbO{sub 3} nanocrystals after a treatment in a reducing atmosphere shows no temperature dependence in the range of 4–300 K. • Magnetization based on density functional theory calculations was compared with the experimental data.

  6. Jazz and the 'art' of medicine: improvisation in the medical encounter.

    Science.gov (United States)

    Haidet, Paul

    2007-01-01

    Improvisation is an important aspect of patient-physician communication. It is also a defining feature of jazz music performance. This essay uses examples from jazz to illustrate principles of improvisation that relate to an individual communication act (ie, building space into one's communication), a physician's communicative style (ie, developing one's voice), and the communicative process of the medical encounter (ie, achieving ensemble). At all 3 levels, the traditions of jazz improvisation can inform efforts to research and teach medical interviewing by fostering a contextualized view of patient-physician communication.

  7. Jazz and the ‘Art’ of Medicine: Improvisation in the Medical Encounter

    Science.gov (United States)

    Haidet, Paul

    2007-01-01

    Improvisation is an important aspect of patient-physician communication. It is also a defining feature of jazz music performance. This essay uses examples from jazz to illustrate principles of improvisation that relate to an individual communication act (ie, building space into one’s communication), a physician’s communicative style (ie, developing one’s voice), and the communicative process of the medical encounter (ie, achieving ensemble). At all 3 levels, the traditions of jazz improvisation can inform efforts to research and teach medical interviewing by fostering a contextualized view of patient-physician communication. PMID:17389542

  8. Magnetic critical behavior of the Ising model on fractal structures

    Science.gov (United States)

    Monceau, Pascal; Perreau, Michel; Hébert, Frédéric

    1998-09-01

    The critical temperature and the set of critical exponents (β,γ,ν) of the Ising model on a fractal structure, namely the Sierpiński carpet, are calculated from a Monte Carlo simulation based on the Wolff algorithm together with the histogram method and finite-size scaling. Both cases of periodic boundary conditions and free edges are investigated. The calculations have been done up to the seventh iteration step of the fractal structure. The results show that, although the structure is not translationally invariant, the scaling behavior of thermodynamical quantities is conserved, which gives a meaning to the finite-size analysis. Although some discrepancies in the values of the critical exponents occur between periodic boundary conditions and free edges, the effective dimension obtained through the Rushbrooke and Josephson's scaling law have the same value in both cases. This value is slightly but significantly different from the fractal dimension.

  9. Influence of the structural properties on the pseudocritical magnetic behavior of single-wall ferromagnetic nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Salazar-Enriquez, C.D. [PCM Computational Applications, Universidad Nacional de Colombia - Sede Manizales, A.A. 127 Manizales (Colombia); Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.co [PCM Computational Applications, Universidad Nacional de Colombia - Sede Manizales, A.A. 127 Manizales (Colombia); Restrepo, J. [Grupo de Magnetismo y Simulacion Gplus, Instituto de Fisica, Universidad de Antioquia, A.A. 1226 Medellin (Colombia)

    2012-04-15

    In this work we address the influence of the crystalline structure, concretely when the system under study is formed by square or hexagonal unit cells, upon the magnetic properties and pseudocritical behavior of single-wall ferromagnetic nanotubes. We focus not only on the effect of the geometrical shape of the unit cell but also on their dimensions. The model employed is based on the Monte Carlo method, the Metropolis dynamics and a nearest neighbors classical Heisenberg Hamiltonian. Magnetization per magnetic site, magnetic susceptibility, specific heat and magnetic energy were computed. These properties were computed varying the system size, unit cell dimension and temperature. The dependence of the nearest neighbor exchange integral on the nanotubes geometrical characteristics is also discussed. Results revealed a strong influence of the system topology on the magnetic properties caused by the difference in the coordination number between square and hexagonal unit cell. Moreover, the nanotubes diameter influence on magnetic properties is only observed at very low values, when the distance between atoms is less than it, presented by the 2D sheet. On the other hand, it was concluded that the surface-related finite-size effects do not influence the magnetic nanotubes properties, contrary to the case of other nano-systems as thin films and nanoparticles among others. - Highlights: Black-Right-Pointing-Pointer Unit cell geometry has strong influence on the magnetic properties in ferromagnetic nanotubes. Black-Right-Pointing-Pointer The nanotube diameter increase produces a decrease of interaction between nearest neighbor. Black-Right-Pointing-Pointer Surface-related finite-size effects do not influence the magnetic nanotubes properties.

  10. Positron Annihilation Behaviors and Magnetic Properties of Single-ph.ase Nd2Fe14B and Nanocomposite

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Positron annihilation behaviors have been studied in the single phase Nd2Fe14B magnet and the nanocomposite Nd2Fe14B/α-Fe magnet, prepared by melt spinning. The results showed that the number of vacancy-cluster at grain boundaries increases with increasing annealing temperature for the both types of magnets. The increase of this kind of defect can improve the coercivity of the single-phase magnet. Conversely, the increase of vacancy-cluster amount leads to decreasing of the coercivity for the nanocomposite magnet. It implies that the mechanism of dominant magnetic hardening for the two types of magnets is different, and the domain walls pinning mechanism in the single-phase magnet and the reversal magnetization nucleation mechanism in the nanocomposite magnet operate, respectively.

  11. Structural tailoring effects on the magnetic behavior of symmetric and asymmetric cubane-type Ni complexes.

    Science.gov (United States)

    Ponomaryov, Alexey N; Kim, Namseok; Hwang, Jaewon; Nojiri, Hiroyuki; van Tol, Johan; Ozarowski, Andrew; Park, Jena; Jang, Zeehoon; Suh, Byoungjin; Yoon, Sungho; Choi, Kwang-Yong

    2013-06-01

    Using two kinds of carboxylate ligands with small but significant differences in steric size, symmetric and asymmetric Fe(II) and Ni(II) cubanes have been synthesized in a controlled fashion. Fast sweeping pulsed field measurements showed magnetization hysteresis loops for two cubane-type molecular complexes, [Ni4(μ-OMe)4(O2CAr(4F-Ph))4(HOMe)8] and [Ni4(μ-OMe)4(O2CAr(Tol))4(HOMe)6], thus suggesting single-molecule magnet behavior. To differentiate the magnetic properties between the symmetric and asymmetric cubanes, detailed electron paramagnetic resonance (EPR) measurements were performed. From the EPR data, taken at various frequencies and temperatures, zero-field splitting parameters D, E, and other higher-order parameters for both cubane samples were extracted. Compared to the symmetric Ni-cubane, the asymmetric one shows an increase in the D and E values by about 20%, thereby suggesting structural engineering effects on the magnetic properties. By using the magnetic parameters determined by EPR, a static magnetization curve at 2 K and a temperature dependence of the magnetic susceptibility were simulated. A good agreement between theoretical and experimental data confirms the validity of the values obtained from EPR measurements.

  12. Magnetically induced electrodeposition of Zn-Ni alloy coatings and their corrosion behaviors

    Science.gov (United States)

    Rao, Vaishaka R.; Bangera, Kasturi V.; Hegde, A. Chitharanjan

    2013-11-01

    The less magnetic features of Zn-Ni alloy compared to Fe-Ni and Fe-Co alloys made it interesting to develop them under the influence of applied magnetic field. In this regard, the effects of a magnetic field (B) applied in a direction parallel and perpendicular to the nominal current, during electrodeposition process of Zn-Ni alloy have been investigated by means of X-ray diffraction and EDX analysis. The modification of crystal orientation by superimposition of a varying magnetic field is studied for alloys of constant nickel content (8 a %.), deposited at optimal current density (j) of 3.0 A dm-2. The effect of magnetic field on crystallographic orientation and hence the corrosion behaviors of the coatings were studied. The preferential orientations (101) and (002) of the zinc phase and (330) γ-Ni5Zn21 phase are always favored to exist with parallel and perpendicular magnetic field. The preferential (321) γ-Ni5Zn21 orientation is found to be the characteristic of perpendicular magnetic field. Further, Zn (100) orientation is found to be non-responsive to the effect of parallel magnetic field. The coatings developed using perpendicular magnetic field is more corrosion resistant compare to that for parallel magnetic field. This is attributed to the additional (321) γ-Ni5Zn21 orientations. The changes in the phase structure of the coatings deposited at different magnetic field are attributed to the effect caused by the magnetic convection induced in the electrolytic solution, called MHD effect (magneto-hydrodynamic effect). The chemical composition of the alloy was found to be same in both natural and magnetically induced deposition due to constant Ni content in the bath. The variation in the surface morphology of the coatings was studied by scanning electron microscopy (SEM). The Zn-Ni alloy coating deposited at 0.8 T perpendicular B showed the highest corrosion resistance (with corrosion rate=0.26×10-2 mm y-1) compared to the one with no B (corrosion rate=14

  13. Effects of the random field on the magnetic behavior of nanowires with core/shell morphology

    Energy Technology Data Exchange (ETDEWEB)

    Zaim, A., E-mail: ah_zaim@yahoo.fr [Laboratoire Physique des Matériaux et Modélisation des Systèmes (LP2MS), Unité Associée au CNRST-URAC: 08, Faculty of Sciences, University Moulay Ismail, B.P. 11201, Zitoune, Meknes (Morocco); Kerouad, M., E-mail: kerouad@fs-umi.ac.ma [Laboratoire Physique des Matériaux et Modélisation des Systèmes (LP2MS), Unité Associée au CNRST-URAC: 08, Faculty of Sciences, University Moulay Ismail, B.P. 11201, Zitoune, Meknes (Morocco); Boughrara, M. [Laboratoire Physique des Matériaux et Modélisation des Systèmes (LP2MS), Unité Associée au CNRST-URAC: 08, Faculty of Sciences, University Moulay Ismail, B.P. 11201, Zitoune, Meknes (Morocco)

    2013-04-15

    We have used the effective field theory based on probability distribution method to investigate the hysteresis behavior of the magnetic nanowires with core/shell morphology in a random magnetic field. The hysteresis curves are obtained for different values of the random magnetic field, both ferromagnetic and antiferromagnetic couplings between the shell and the core are considered. A number of characteristic behaviors are find, such as the existence of double or triple hysteresis loops for appropriate values of the system parameters affected by the random magnetic field, temperature, and interfacial coupling. -- Highlights: ► The hysteresis behavior of the Ising nanowires has been studied by EFT. ► The effects of the random field on the hysteresis loops have been examined. ► The hysteresis loops are obtained for different values of the interfacial coupling constant. ► The triple hysteresis loops occur for the larger antiferromagnetic coupling constant. ► The dependence of the coercive field on the temperature is investigated.

  14. Modeling the nuclear magnetic resonance behavior of lung: from electrical engineering to critical care medicine.

    Science.gov (United States)

    Cutillo, A G; Ailion, D C

    1999-01-01

    The present article reviews the basic principles of a new approach to the characterization of pulmonary disease. This approach is based on the unique nuclear magnetic resonance (NMR) properties of the lung and combines experimental measurements (using specially developed NMR techniques) with theoretical simulations. The NMR signal from inflated lungs decays very rapidly compared with the signal from completely collapsed (airless) lungs. This phenomenon is due to the presence of internal magnetic field inhomogeneity produced by the alveolar air-tissue interface (because air and water have different magnetic susceptibilities). The air-tissue interface effects can be detected and quantified by magnetic resonance imaging (MRI) techniques using temporally symmetric and asymmetric spin-echo sequences. Theoretical models developed to explain the internal (tissue-induced) magnetic field inhomogeneity in aerated lungs predict the NMR lung behavior as a function of various technical and physiological factors (e.g., the level of lung inflation) and simulate the effects of various lung disorders (in particular, pulmonary edema) on this behavior. Good agreement has been observed between the predictions obtained from the mathematical models and the results of experimental NMR measurements in normal and diseased lungs. Our theoretical and experimental data have important pathophysiological and clinical implications, especially with respect to the characterization of acute lung disease (e.g., pulmonary edema) and the management of critically ill patients.

  15. A family of 'windmill'-like {Cu6Ln12} complexes exhibiting single-molecule magnetism behavior and large magnetic entropy changes.

    Science.gov (United States)

    Alexandropoulos, Dimitris I; Poole, Katye M; Cunha-Silva, Luis; Ahmad Sheikh, Javeed; Wernsdorfer, Wolfgang; Christou, George; Stamatatos, Theocharis C

    2017-03-31

    A family of nanosized {Cu6Ln12} clusters with a 'windmill'-like topology was prepared from the employment of 2,6-diacetylpyridine dioxime, in conjunction with bridging N3(-), in 3d/4f-metal chemistry; the octadecanuclear compounds exhibit single-molecule magnetism behavior and large magnetic entropy changes, depending on the 4f-metal ion present.

  16. Magnetic navigation behavior and the oceanic ecology of young loggerhead sea turtles.

    Science.gov (United States)

    Putman, Nathan F; Verley, Philippe; Endres, Courtney S; Lohmann, Kenneth J

    2015-04-01

    During long-distance migrations, animals navigate using a variety of sensory cues, mechanisms and strategies. Although guidance mechanisms are usually studied under controlled laboratory conditions, such methods seldom allow for navigation behavior to be examined in an environmental context. Similarly, although realistic environmental models are often used to investigate the ecological implications of animal movement, explicit consideration of navigation mechanisms in such models is rare. Here, we used an interdisciplinary approach in which we first conducted lab-based experiments to determine how hatchling loggerhead sea turtles (Caretta caretta) respond to magnetic fields that exist at five widely separated locations along their migratory route, and then studied the consequences of the observed behavior by simulating it within an ocean circulation model. Magnetic fields associated with two geographic regions that pose risks to young turtles (due to cold wintertime temperatures or potential displacement from the migratory route) elicited oriented swimming, whereas fields from three locations where surface currents and temperature pose no such risk did not. Additionally, at locations with fields that elicited oriented swimming, simulations indicate that the observed behavior greatly increases the likelihood of turtles advancing along the migratory pathway. Our findings suggest that the magnetic navigation behavior of sea turtles is intimately tied to their oceanic ecology and is shaped by a complex interplay between ocean circulation and geomagnetic dynamics.

  17. Behavior of Medium-frequency Core Loss in Fe-based Nanocrystalline Soft Magnetic Alloys

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The dependences of the power loss per cycle on frequency have been investigated in the ranges of 100 Hz< f <25000 Hz and 0.1 T< Brn <1.0 T for three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloys. The measured and calculated results showed that the total ipower loss per cycle clearly exhibited a nonlinear behavior in the range below 3 kHz~5 kHz depending on both the magnetic state and the value of Bm, whereas it showed a quasi-linear behavior above this range. The total loss was decomposed into hysteresis loss, classical eddy current loss and excess loss, the obvious nonlinear behavior has been confirmed to be completely determined by the dependence of the excess loss on frequency. It has been indicated that the change rate of the excess loss per cycle with respect to frequency sharp decreases with increasing frequency in the range below about 3 kHz~5 kHz, herease the rate of change slowly varies above this range, thus leading to the quasilinear behavior of the total loss per cycle. In this paper, some linear expressions of the total loss per cycle has been given in a wider medium-frequency segment, which can be used for roughly estimating the total loss.

  18. Stemming the Flow of Improvised Explosive Device Making Materials through Global Export Control Regimes

    Science.gov (United States)

    2012-09-01

    in place. 54 Annabel Z. Dodd, The Essential Guide to Telecommunications (Upper Saddle River...Estimates: Joint Improvised Explosive Device Defeat Organization. Department of the Army, 2011. Dodd, Annabel Z. The Essential Guide to Telecommunications

  19. Neural correlates of lyrical improvisation: an FMRI study of freestyle rap

    National Research Council Canada - National Science Library

    Liu, Siyuan; Chow, Ho Ming; Xu, Yisheng; Erkkinen, Michael G; Swett, Katherine E; Eagle, Michael W; Rizik-Baer, Daniel A; Braun, Allen R

    2012-01-01

    The neural correlates of creativity are poorly understood. Freestyle rap provides a unique opportunity to study spontaneous lyrical improvisation, a multidimensional form of creativity at the interface of music and language...

  20. Improviser non verbalement pour l’apprentissage de la langue parlée

    Directory of Open Access Journals (Sweden)

    Francine Chaîné

    2015-04-01

    Full Text Available Un texte réflexif sur la pratique de l'improvisation dans un contexte scolaire en vue d'apprendre la langue parlée. D'aucun penserait que l'improvisation verbale est le moyen par excellence pour faire l'apprentissage de la langue, mais l'expérience nous a fait découvrir la richesse de l'improvisation non-verbale suivie de prise de parole sur la pratique comme moyen privilégié. L'article est illustré d'un atelier d'improvisation-non verbale s'adressant à des enfants ou à des adolescents.

  1. Homicide by improvised explosive device made out of firecrackers.

    Science.gov (United States)

    Verma, S K

    2001-10-01

    Explosion is a phenomenon resulting from a sudden release of energy dissipated by: (1) blast wave; (2) translocation of objects; and (3) generation of heat. There are different types of explosive devices varying from sophisticated military bombs to simple firecrackers. These are made from various kinds of explosive materials. Sophisticated bombs are used in war and military operations to kill one's enemies, while simple firecrackers are meant for expressing joy and celebration. Here, the author reports an unusual case of homicide by the manufacture of an improvised explosive device from simple firecrackers. In India, these firecrackers are widely and freely available all over the country. The case highlights the fatal hazard resulting from easy access to these potentially dangerous devices, apart from the environmental pollution produced by their large scale use at the time of festivals in this country.

  2. Improvisation and Variation: Post-Communist Bulgaria Challenges National Folklore Tradition

    Directory of Open Access Journals (Sweden)

    Elka Agoston-Nikolova

    2008-08-01

    Full Text Available The paper discusses the tension in post-totalitarian Bulgaria betweenthe national folklore tradition of Communist times with government sanctioned state ensembles and festivals and age-old Balkan multiculturalism now represented in a westernized free-market consumer society, where spontaneity and improvisation bridge the urban and the rural, the local and the global. Folk pop, folk jazz or other mixed genres reverberate with humor , parody and, above all, freedom and love of improvisation.

  3. The acquisition of socio-motor improvisation in the mirror game.

    Science.gov (United States)

    Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

    2016-04-01

    Socio-motor improvisation is defined as the creative action of two or more people without a script or anticipated preparation. It is evaluated through two main parameters: movement synchronization and movement richness. Experts in art (e.g., dance, theater or music) are known to exhibit higher synchronization and to perform richer movements during interpersonal improvisation, but how these competences evolve over time is largely unknown. In the present study, we investigated whether performing more synchronized and richer movements over time can promote the acquisition of improvisation. Pairs of novice participants were instructed to play an improvisation mirror game in three different sessions. Between sessions, they performed an unintended interpersonal coordination task in which synchronization and richness were manipulated, resulting in four different groups of dyads. Our results demonstrate that synchronization during improvisation improved for all groups whereas movement richness only enhanced for dyads that performed synchronized movements during unintended coordination tasks. Our findings suggest that movement synchrony contributes more than movement richness to the acquisition of socio-motor improvisation in the mirror game.

  4. The mirror game as a paradigm for studying the dynamics of two people improvising motion together.

    Science.gov (United States)

    Noy, Lior; Dekel, Erez; Alon, Uri

    2011-12-27

    Joint improvisation is the creative action of two or more people without a script or designated leader. Examples include improvisational theater and music, and day-to-day activities such as conversations. In joint improvisation, novel action is created, emerging from the interaction between people. Although central to creative processes and social interaction, joint improvisation remains largely unexplored due to the lack of experimental paradigms. Here we introduce a paradigm based on a theater practice called the mirror game. We measured the hand motions of two people mirroring each other at high temporal and spatial resolution. We focused on expert actors and musicians skilled in joint improvisation. We found that players can jointly create novel complex motion without a designated leader, synchronized to less than 40 ms. In contrast, we found that designating one player as leader deteriorated performance: The follower showed 2-3 Hz oscillation around the leader's smooth trajectory, decreasing synchrony and reducing the range of velocities reached. A mathematical model suggests a mechanism for these observations based on mutual agreement on future motion in mirrored reactive-predictive controllers. This is a step toward understanding the human ability to create novelty by improvising together.

  5. Creativity as a distinct trainable mental state: An EEG study of musical improvisation.

    Science.gov (United States)

    Lopata, Joel A; Nowicki, Elizabeth A; Joanisse, Marc F

    2017-03-18

    Alpha-band EEG was used to index how creative mental states relate to the creation of artistic works in skilled musicians. We contrasted differences in frontal upper alpha-band activity between tasks with high and low creativity demands by recording EEGs while skilled musicians listened to, played back, and improvised jazz melodies. Neural responses were compared for skilled musicians with training in musical improvisation versus those who had no formal improvisation training. Consistent with our hypotheses, individuals showed increased frontal upper alpha-band activity during more creative tasks (i.e., improvisation) compared to during less creative tasks (i.e., rote playback). Moreover, this effect was greatest for musicians with formal improvisation training. The strength of this effect also appeared to modulate the quality of these improvisations, as evidenced by significant correlations between upper alpha EEG power and objective post-hoc ratings of individuals' performances. These findings support a conceptualization of creativity as a distinct mental state and suggest spontaneous processing capacity is better nurtured through formal institutional training than informal.

  6. Modeling the Non Linear Behavior of a Magnetic Fault Current Limiter

    Directory of Open Access Journals (Sweden)

    P. R. Wilson

    2015-11-01

    Full Text Available Fault Current Limiters are used in a wide array of applications from small circuit protection at low power levels to large scale high power applications which require superconductors and complex control circuitry. One advantage of  passive fault current limiters (FCL is the automatic behavior that is dependent on the intrinsic properties of the circuit elements rather than on a complex feedback control scheme making this approach attractive for low cost applications and also where reliability is critical. This paper describes the behavioral modeling of a passive Magnetic FCL and its potential application in practical circuits.

  7. Nearly complete regression of tumors via collective behavior of magnetic nanoparticles in hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, C L [Materials Science and Engineering Laboratory, NIST, Gaithersburg, MD 20899-8552 (United States); Jackson, A J; Borchers, J A [NIST Center for Neutron Research, Gaithersburg, MD 20899-8562 (United States); Hoopes, P J; Strawbridge, R [Dartmouth College, Hanover, NH 03755 (United States); Foreman, A R; Ivkov, R [Triton BioSystems, Incorporated, Chelmsford, MA 01824 (United States); Van Lierop, J [Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB, R3T 2N2 (Canada); Gruettner, C, E-mail: cindi.dennis@nist.go, E-mail: rivkov@jhmi.ed [Mic romod Partikeltechnologie GmbH, 18119 Rostock-Warnemuende (Germany)

    2009-09-30

    One potential cancer treatment selectively deposits heat to the tumor through activation of magnetic nanoparticles inside the tumor. This can damage or kill the cancer cells without harming the surrounding healthy tissue. The properties assumed to be most important for this heat generation (saturation magnetization, amplitude and frequency of external magnetic field) originate from theoretical models that assume non-interacting nanoparticles. Although these factors certainly contribute, the fundamental assumption of 'no interaction' is flawed and consequently fails to anticipate their interactions with biological systems and the resulting heat deposition. Experimental evidence demonstrates that for interacting magnetite nanoparticles, determined by their spacing and anisotropy, the resulting collective behavior in the kilohertz frequency regime generates significant heat, leading to nearly complete regression of aggressive mammary tumors in mice.

  8. Photo-activation of Single Molecule Magnet Behavior in a Manganese-based Complex

    Science.gov (United States)

    Fetoh, Ahmed; Cosquer, Goulven; Morimoto, Masakazu; Irie, Masahiro; El-Gammal, Ola; El-Reash, Gaber Abu; Breedlove, Brian K.; Yamashita, Masahiro

    2016-03-01

    A major roadblock to fully realizing molecular electronic devices is the ability to control the properties of each molecule in the device. Herein we report the control of the magnetic properties of single-molecule magnets (SMMs), which can be used in memory devices, by using a photo-isomerizable diarthylenthene ligand. Photo-isomerization of the diarylethene ligand bridging two manganese salen complexes with visible light caused a significant change in the SMM behavior due to opening of the six-membered ring of diarylethene ligand, accompanied by reorganization of the entire molecule. The ring-opening activated the frequency-dependent magnetization of the complex. Our results are a major step towards the realization of molecular memory devices composed of SMMs because the SMM behaviour can be turned on and off simply by irradiating the molecule.

  9. Effects of High Magnetic Field on Solidification and Corrosion Behaviors of Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The solidification behaviors of AZ61 magnesium alloy under a high magnetic field were studied. The corrosion property of AZ61 alloy was investigated in a solution of 3.5 mol/L NaCl by measuring electrochemical polarization. The results show that the high magnetic field can refine microstructure and benefit aluminum transfer.The crystal of α-Mg is induced to orient with their c-axis parallel to the magnetic field. The corrosion studies indicate that different crystal plane of magnesium has different corrosion property. The passivating films on the a- and b-planes have higher corrosion resistance than that on the c-plane. Aligned structure affects the corrosion property of AZ61 magnesium alloy.

  10. Scaling behavior of individual barkhausen avalanches in nucleation-mediated magnetization reversal processes

    Energy Technology Data Exchange (ETDEWEB)

    Im, Mi-Young; Fischer, Peter; Kim, Dong-Hyun; Shin, Sung-Chul

    2009-11-09

    We report the scaling behavior of Barkhausen avalanches along the hysteresis loop of a CoCrPt alloy film with perpendicular magnetic anisotropy for every field step of 200 Oe. Individual Barkhausen avalanches are directly observed via high-resolution soft X-ray microscopy with a spatial resolution of 15 nm. The Barkhausen avalanches exhibit a power-law scaling behavior, where the scaling exponent of the power-law distribution drastically changes from 1 {+-} 0.04 to 1.47 {+-} 0.03 as the applied magnetic field approaches the coercivity of the CoCrPt film. We infer that this is due to the coupling of adjacent domains.

  11. Magnetically induced electrodeposition of Zn–Ni alloy coatings and their corrosion behaviors

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Vaishaka R. [Electrochemistry Research Laboratory, Department of Chemistry, National Institute of Technology Karnataka, NITK, Surathkal, Srinivasnagar 575025, Mangalore, Karnataka (India); Bangera, Kasturi V. [Electrochemistry Research Laboratory, Department of Chemistry, National Institute of Technology Karnataka, NITK, Surathkal, Srinivasnagar 575025, Mangalore, Karnataka (India); Electrochemistry Research Laboratory, Department of Physics, National Institute of Technology Karnataka, NITK, Surathkal, Srinivasnagar, 575025, Mangalore, Karnataka (India); Hegde, A. Chitharanjan, E-mail: hegdeac@rediffmail.com [Electrochemistry Research Laboratory, Department of Chemistry, National Institute of Technology Karnataka, NITK, Surathkal, Srinivasnagar 575025, Mangalore, Karnataka (India)

    2013-11-15

    The less magnetic features of Zn–Ni alloy compared to Fe–Ni and Fe–Co alloys made it interesting to develop them under the influence of applied magnetic field. In this regard, the effects of a magnetic field (B) applied in a direction parallel and perpendicular to the nominal current, during electrodeposition process of Zn–Ni alloy have been investigated by means of X-ray diffraction and EDX analysis. The modification of crystal orientation by superimposition of a varying magnetic field is studied for alloys of constant nickel content (8 a %.), deposited at optimal current density (j) of 3.0 A dm{sup −2}. The effect of magnetic field on crystallographic orientation and hence the corrosion behaviors of the coatings were studied. The preferential orientations (101) and (002) of the zinc phase and (330) γ-Ni{sub 5}Zn{sub 21} phase are always favored to exist with parallel and perpendicular magnetic field. The preferential (321) γ-Ni{sub 5}Zn{sub 21} orientation is found to be the characteristic of perpendicular magnetic field. Further, Zn (100) orientation is found to be non-responsive to the effect of parallel magnetic field. The coatings developed using perpendicular magnetic field is more corrosion resistant compare to that for parallel magnetic field. This is attributed to the additional (321) γ-Ni{sub 5}Zn{sub 21} orientations. The changes in the phase structure of the coatings deposited at different magnetic field are attributed to the effect caused by the magnetic convection induced in the electrolytic solution, called MHD effect (magneto-hydrodynamic effect). The chemical composition of the alloy was found to be same in both natural and magnetically induced deposition due to constant Ni content in the bath. The variation in the surface morphology of the coatings was studied by scanning electron microscopy (SEM). The Zn–Ni alloy coating deposited at 0.8 T perpendicular B showed the highest corrosion resistance (with corrosion rate=0.26×10{sup

  12. Magnetic properties and crystallization behavior of nanocrystalline FeSiBPCuAl alloys

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Magnetic properties and crystallization behavior of nanocrystalline (Fe83.3Si4B8P4Cu0.7)100-xAlx (x=0-1.5 at%) alloys were investigated in this study.Experimental results show that coercive force decreases and saturation magnetization slightly decreases with the increase of Al content,but the glass forming ability has been improved at the same time.Crystallization behavior including the evolution of microstructure has also been studied.The growth of α-Fe precipitated from the matrix is quick when it is annealed by conventional method and the mean size of α-Fe grains increases from below 2-3 nm to 18-29 nm.Nanocrystalline (Fe83.3Si4B8P4Cu0.7)99Al1 alloy with coercive force of 8.9 A/m and saturation magnetization of 187 emu/g is probably a promising candidate in the field of soft magnetic materials.

  13. Microstructure and magnetic behavior of Mn doped GeTe chalcogenide semiconductors based phase change materials

    Science.gov (United States)

    Adam, Adam Abdalla Elbashir; Cheng, Xiaomin; Abuelhassan, Hassan H.; Miao, Xiang Shui

    2017-06-01

    Phase-change materials (PCMs) are the most promising candidates to be used as an active media in the universal data storage and spintronic devices, due to their large differences in physical properties of the amorphous-crystalline phase transition behavior. In the present study, the microstructure, magnetic and electrical behaviors of Ge0.94Mn0.06Te thin film were investigated. The crystallographic structure of Ge0.94Mn0.06Te thin film was studied sing X-ray diffractometer (XRD) and High Resolution Transmission Electron Microscope (HR-TEM). The XRD pattern showed that the crystallization structure of the film was rhombohedral phase for GeTe with a preference (202) orientation. The HR-TEM image of the crystalline Ge0.94Mn0.06Te thin film demonstrated that, there were two large crystallites and small amorphous areas. The magnetization as a function of the magnetic field analyses of both amorphous and crystalline states showed the ferromagnetic hysteretic behaviors. Then, the hole carriers concentration of the film was measured and it found to be greater than 1021 cm-3 at room temperature. Moreover, the anomalous of Hall Effect (AHE) was clearly observed for the measuring temperatures 5, 10 and 50 K. The results demonstrated that the magnitude of AHE decreased when the temperature was increasing.

  14. Affinity adsorption and separation behaviors of avidin on biofunctional magnetic nanoparticles binding to iminobiotin.

    Science.gov (United States)

    Sun, Shuguo; Ma, Meihu; Qiu, Ning; Huang, Xi; Cai, Zhaoxia; Huang, Qun; Hu, Xin

    2011-11-01

    Knowing the adsorption behavior of target proteins on biofunctional magnetic nanoparticles is of great importance for the separation and purification of proteins. Adsorption behaviors of avidin on biofunctional magnetic nanoparticles binding to iminobiotin were investigated under different conditions of temperature, pH, ionic strength, and feed avidin concentration. Biofunctionalization of the non-functional nanoparticles was performed, coupled with iminobiotin. Characterization of the particles was carried out using transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The results showed the avidin adsorption behaviors were mainly dependent on affinity interaction between avidin and iminobiotin coupled with the nanoparticles, which exhibited temperature, pH, ionic strength, and feed avidin concentration sensitivity. Maximum avidin adsorption capacity was achieved as 225 mg avidin/g biofunctional nanoparticles. Results were well fitted to the Langmuir isotherm model with the feed avidin concentration of less than 45 μg/ml. Based on the experiments above, the biofunctional magnetic nanoparticles were used to separate avidin from treated egg-white solution containing large amounts of other proteins. The avidin was isolated in 92% yield with an optical purity of more than 98.5% according to the HPSEC data. The regeneration of these nanoparticles was also studied and almost 87.3% of avidin could still be recovered by these regenerated nanoparticles. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Magnetic behavior of Ca{sub 2}NiWO{sub 6} double perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, C.A. [Area de Quimica General e Inorganica ' Dr. G.F.Puelles' , Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700 San Luis (Argentina); Curiale, J. [Centro Atomico Bariloche and Instituto Balseiro (UNCuyo), CNEA, Av. Bustillo 9500 (R8402AGP) S. C. de Bariloche, RN (Argentina); Viola, M. del C. [Area de Quimica General e Inorganica ' Dr. G.F.Puelles' , Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700 San Luis (Argentina); Pedregosa, J.C. [Area de Quimica General e Inorganica ' Dr. G.F.Puelles' , Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700 San Luis (Argentina)]. E-mail: jpedreg@unsl.edu.ar; Sanchez, R.D. [Centro Atomico Bariloche and Instituto Balseiro (UNCuyo), CNEA, Av. Bustillo 9500 (R8402AGP) S. C. de Bariloche, RN (Argentina)]. E-mail: rodo@cab.cnea.gov.ar

    2007-09-01

    Polycrystalline Ca{sub 2}NiWO{sub 6} double perovskite has been prepared by solid-state reaction at 1150 C. The crystal structure of this material has been confirmed by X-ray powder diffraction (XRD). At room temperature, the crystal structure is monoclinic, space group P2{sub 1}/n, with a=5.4061(2) A, b=5.5389(2) A, c=7.6895(3) A, {beta}=90.232(2){sup o}. Magnetic susceptibility and electron spin resonance experiments on Ca{sub 2}NiWO{sub 6} show at high temperature a Curie-Weiss behavior with a {theta}=-75 K. From the Curie-Weiss behavior, the effective magnetic moment is 2.85{mu} {sub B}, which is in agreement with the presence of Ni{sup 2+} in the system. At low temperatures, below 52.5(0.2) K, the magnetic susceptibility shows antiferromagnetic behavior. From the experimental data and the mean field theory of antiferromagnetism we estimated the Ni interactions among the nearest Ni neighbors and the second nearest Ni neighbors.

  16. Recent studies in the behavioral toxicology of ELF electric and magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Lovely, R.H.

    1988-01-01

    Behavioral responses to ELF electric and magnetic fields are reviewed starting with the simple sensory awareness or detection by an animal and moving on through more-complicated behavioral responses such as behavior that averts exposure. The literature selected in this review is taken primarily from the area of behavioral toxicology. As such, it does not review work on specialized response systems to ELF fields. The most notable of these omitted specialized response systems are electroreception, which occurs in a number of fish species, and homing/navigation and communication of the location of food that occurs in several species of birds and in honeybees, respectively. The toxicologic orientation of most researches that evaluate the effects of exposure to ELF electric and magnetic fields has been influenced primarily by the missions of DOE and the power industry programs to determine the health effects of power frequency (50- and 60-Hz) electric and magnetic fields. Because of these large programmatic efforts, most of the recent research has in fact been done at 50 or 60 Hz. In the context of the above limitations, remarkably few robust behavioral effects have been reported. Those that have been reported probably relate to an animal's perception of the electric field, although there are some exceptions to this generalization. The apparent lack of deleterious effects in animals is consistent with recent studies on humans that have been conducted in the UK. With this in mind, it is tempting to conclude that exposure to an ELF field is a rather innocuous event and, other than possible mini-shocks, is without hazard. 43 references.

  17. Synthesis of colloidal silver iron oxide nanoparticles--study of their optical and magnetic behavior.

    Science.gov (United States)

    Kumar, Anil; Singhal, Aditi

    2009-07-22

    Silver iron oxide nanoparticles of fairly small size (average diameter approximately 1 nm) with narrow size distribution have been synthesized by the interaction of colloidal beta- Fe2O3 and silver nanoparticles. The surface morphology and size of these particles have been analyzed by using atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Their structural analysis has been carried out by employing x-ray diffraction (XRD), selected-area electron diffraction (SAED), optical and infrared (IR) spectroscopic techniques. The ageing of these particles exhibits the formation of self-assembly, possibly involving weak supramolecular interactions between Ag(I)O4 and Fe(III)O4 species. These particles display the onset of absorption in the near-infrared region and have higher absorption coefficient in the visible range compared to that of its precursors. Magnetic measurements reveal an interesting transition in their magnetic behavior from diamagnetic to superparamagnetic. The magnetic moment of these particles attains a limiting value of about 0.19 emu cm(-2), which is more than two times higher than that of colloidal beta- Fe2O3. With enhanced optical and magnetic properties, this system is suggested to have possible applications in optoelectronic and magnetic devices.

  18. Heat-Affected Behavior of the Magnetic Properties of Iron Nano-Particles

    Institute of Scientific and Technical Information of China (English)

    柳刚; 吕楠; 秦伯雄; 范荣焕; 郭院波

    2004-01-01

    The high surface energy makes metal nano-particles reactive and easy to get oxidized or burned in the open air, which results in decreasing or entirely losing their functions and properties. In this paper, the mag netic property behavior of iron nano-particle, which is one kind of the typical magnetic nano-materials, has been investigated. The iron nano-particles were heated to different temperatures in an open-air stove. After that, they were firstly examined by TEM to observe the changes of their outline of shapes and then measured by VSM to trace the changes of their magnetic properties. The test results show that iron nano-particles can keep their magnetic property with saturation magnetic induction intensity B, around 136-161 emu/g, remanent magnetic induction intensity Br around 14.8-17.4 emu/g and coercive force Hc around 290-302 Oe when the temperature goes up to 523 K. The explanation to such outstanding oxidization-proof ability has been given that there exists a single crystal and lattice-shared Gamma-Fe2O3 shell covering the pure iron core, which prevents the spherical iron nano-particles from further oxidization.

  19. Surface magnetic behavior of nearly zero magnetostrictive Co-rich amorphous microwires

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, J. E-mail: wapgoesj@sc.ehu.es; Chizhik, A.; Zhukov, A.; Blanco, J.M

    2003-03-01

    Investigations on the magnetic reversal in amorphous wire (diameter 125 {mu}m) of nominal composition (Co{sub 94}Fe{sub 6}){sub 72.5}Si{sub 12.5}B{sub 15} and glass-covered microwires (diameter around 20 {mu}m) of nominal composition (Co{sub 1-x}Mn{sub x}){sub 75}Si{sub 10}B{sub 15} (0.07magnetic behavior of the amorphous wire after annealing (without and under torsion stress) have been studied. The analysis of the obtained results allows to establish that the outer shell of the as-quenched wire consists of circular bamboo domains, in contrast to the annealed wire displaying the existence of domain structure with magnetization directed along the wire axis. Such modification of the domain structure with the thermal treatment could be related to the change of the sign of magnetostriction from negative to positive. The effect of a thermal treatment under torsion stress (torsion annealing) on the shape of the hysteresis loop of the amorphous wire has been also investigated. The Kerr effect measurements of Co-rich microwires with different content in Mn demonstrate the variety of the shape of magnetization reversal loop, which similarly can be attributed to the change of sign and value of the magnetostriction. The rectangular shape of the hysteresis loop in circular magnetic field of the microwire with x=0.07 can be interpreted by considering that the magnetization process takes place by large Barkhausen jumps of circular domain structure, while the rectangular shape of the hysteresis loop with axial magnetic field of the microwire x=0.11 could be connected to large Barkhausen jumps inside the axial domain structure.

  20. The magnetic behavior of the intermetallic compound NdMn{sub 2}Ge{sub 2} studied by magnetization and hyperfine interactions measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bosch-Santos, B., E-mail: brianna@usp.br; Carbonari, A. W.; Cabrera-Pasca, G. A.; Saxena, R. N. [Instituto de Pesquisas Energéticas e Nucleares, Universidade de São Paulo, 05508-000 São Paulo (Brazil); Freitas, R. S. [Instituto de Física, Universidade de São Paulo, CP 66318, 05314-970 São Paulo (Brazil)

    2015-05-07

    The magnetic behavior of the intermetallic compound NdMn{sub 2}Ge{sub 2} was investigated by bulk magnetization measurements and measurements of hyperfine interactions using perturbed γ–γ angular correlation (PAC) spectroscopy. Magnetization measurements indicate the presence of four magnetic transitions associated with the Mn and Nd magnetic sublattices. At high temperatures, magnetic measurements show a change in the slope of the magnetization due to an antiferromagnetic transition around T{sub N} ∼ 425 K and a well defined ferromagnetic transition at T{sub C} ∼ 320 K. Moreover, at ∼210 K a peak is observed in the magnetization curve, which is assigned to the reorientation of the Mn spin, and at ∼25 K an increase in the magnetic moment is also observed, which is ascribed to the ordering of Nd ions. PAC measurements using {sup 140}La({sup 140}Ce) and {sup 111}In({sup 111}Cd) probe nuclei allowed the determination of the temperature dependence of the magnetic hyperfine field (B{sub hf}) at Nd and Mn sites, respectively. PAC results with {sup 111}Cd probe nuclei at Mn sites show that the dependence of B{sub hf} with temperature follows the expected behavior for the host magnetization associated with the magnetic ordering of Mn ions. From these results, the antiferromagnetic transition followed by a ferromagnetic ordering is clearly observed. PAC results with {sup 140}Ce probe nuclei at Nd sites, however, showed a strong deviation from the Brillouin function, which is attributed to the Ce 4f-electron contribution to B{sub hf}.

  1. Strain-Modulated Exchange-Spring Magnetic Behavior in Amorphous Tb-Fe Thin Films

    Science.gov (United States)

    Lee, Taehwan; Panduranga, Mohanchandra Kotekar; Han, Chang Wan; Ortalan, Volkan; Carman, Gregory Paul

    2017-08-01

    This paper studies the room-temperature exchange-spring magnetic behavior of amorphous TbFe films subjected to an applied strain. The cross-sectional composition measurement of the sputter-deposited TbFe film shows a compositional gradient through the thickness. The gradient is near the compensation composition of amorphous TbFe film producing a Tb-dominant region and a Fe-dominant region. The as-deposited film shows a two-step switching behavior with a negative coercive field, while an applied compressive (or tensile) strain eliminates (or enhances) the two-step switching behavior. The strain influence is attributed to the TbFe composition gradient and relatively large magnetoelastic property of the Tb-dominant region as compared to the Fe-dominant one.

  2. Scaling Behavior of Barkhausen Avalanches along the Hysteresis loop in Nucleation-Mediated Magnetization Reversal Process

    Energy Technology Data Exchange (ETDEWEB)

    Im, Mi-Young; Fischer, Peter; Kim, D.-H.; Shin, S.-C.

    2008-10-14

    We report the scaling behavior of Barkhausen avalanches for every small field step along the hysteresis loop in CoCrPt alloy film having perpendicular magnetic anisotropy. Individual Barkhausen avalanche is directly observed utilizing a high-resolution soft X-ray microscopy that provides real space images with a spatial resolution of 15 nm. Barkhausen avalanches are found to exhibit power-law scaling behavior at all field steps along the hysteresis loop, despite their different patterns for each field step. Surprisingly, the scaling exponent of the power-law distribution of Barkhausen avalanches is abruptly altered from 1 {+-} 0.04 to 1.47 {+-} 0.03 as the field step is close to the coercive field. The contribution of coupling among adjacent domains to Barkhausen avalanche process affects the sudden change of the scaling behavior observed at the coercivity-field region on the hysteresis loop of CoCrPt alloy film.

  3. Random crystal field effect on the magnetic and hysteresis behaviors of a spin-1 cylindrical nanowire

    Science.gov (United States)

    Zaim, N.; Zaim, A.; Kerouad, M.

    2017-02-01

    In this work, the magnetic behavior of the cylindrical nanowire, consisting of a ferromagnetic core of spin-1 atoms surrounded by a ferromagnetic shell of spin-1 atoms is studied in the presence of a random crystal field interaction. Based on Metropolis algorithm, the Monte Carlo simulation has been used to investigate the effects of the concentration of the random crystal field p, the crystal field D and the shell exchange interaction Js on the phase diagrams and the hysteresis behavior of the system. Some characteristic behaviors have been found, such as the first and second-order phase transitions joined by tricritical point for appropriate values of the system parameters, triple and isolated critical points can be also found. Depending on the Hamiltonian parameters, single, double and para hysteresis regions are explicitly determined.

  4. On the Current Solar Magnetic Activity using Its Behavior During the Holocene

    Science.gov (United States)

    Inceoglu, Fadil; Simoniello, Rosaria; Faurschou Knudsen, Mads; Karoff, Christoffer; Olsen, Jesper; Turck-Chieze, Sylvaine

    2016-07-01

    Solar modulation potential (SMP) reconstructions based on cosmogenic nuclide records reflect changes in the open solar magnetic field and can therefore help us obtain information on the behavior of the open solar magnetic field over the Holocene period. Using the Greenland Ice Core Project (GRIP) ^{10}Be and IntCal13 ^{14}C records for the overlapping time period spanning between ˜1650 AD to 6600 BC, we first reconstructed the solar modulation potentials and subsequently investigate the statistics of peaks and dips simultaneously occurring in the two SMP reconstructions. Based on the distribution of these events, we propose a method to identify grand minima and maxima periods. We then aim at comparing the Sun's large-scale magnetic field behavior over the last three solar cycles with variations in the SMP reconstruction through the Holocene epoch. To achieve these objectives, we use the IntCal13 ^{14}C data to investigate distinct patterns in the occurrences of grand minima and maxima during the Holocene period. We then check whether these patterns might mimic the recent solar magnetic activity by investigating the evolution of the energy in the Sun's large-scale dipolar magnetic field using the Wilcox Solar Observatory data. The cosmogenic radionuclide data analysis shows that ˜71 % of grand maxima during the period from 6600 BC to 1650 AD were followed by a grand minimum. The characteristics of the occurrences of grand maxima and minima are consistent with the scenario in which the dynamical non-linearity induced by the Lorentz force leads the Sun to act as a relaxation oscillator. This finding implies that the probability for these events to occur is non-uniformly distributed in time, as there is a memory in their driving mechanism, which can be identified via the back-reaction of the Lorentz force.

  5. Electrical and magnetic behavior of iron doped nickel titanate (Fe3+/NiTiO3) magnetic nanoparticles

    Science.gov (United States)

    Lenin, Nayagam; Karthik, Arumugam; Sridharpanday, Mathu; Selvam, Mohanraj; Srither, Saturappan Ravisekaran; Arunmetha, Sundarmoorthy; Paramasivam, Palanisamy; Rajendran, Venkatachalam

    2016-01-01

    Iron doped nickel titanate (Fe3+/NiTiO3) ferromagnetic nanoparticles with different concentrations of Fe (0.2, 0.4, and 0.6 mol) were synthesized using precipitation route with precursor source such as nickel nitrate and iron nitrate solutions. The prepared magnetic nanopowders were investigated through X-ray diffraction (XRD), Fourier transform infrared, scanning electron microscope, X-ray fluorescence, Brunauer-Emmett-Teller, vibrating sample magnetometer, and electrochemical impedance spectroscopy to explore the structural, ferromagnetic, and dielectric properties. The obtained XRD pattern shows formation of iron doped nickel titanate in orthorhombic structure. The crystallite size ranges from 57 to 21 nm and specific surface area ranges from 11 to 137 m2 g-1. The hysteresis loops of nanomagnetic materials show ferromagnetic behavior with higher magnitude of coercivity (Hc) 867-462 Oe. The impedance analysis of ferromagnetic materials explores the ferro-dielectric behavior with enhanced properties of Fe3+/NiTiO3 nanoparticles at higher Fe content.

  6. Single-molecule magnet behavior in 2,2’-bipyrimidine-bridged dilanthanide complexes

    Directory of Open Access Journals (Sweden)

    Wen Yu

    2016-01-01

    Full Text Available A series of 2,2’-bipyrimidine-bridged dinuclear lanthanide complexes with the general formula [Ln(tmhd3]2bpm (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate, bpm = 2,2’-bipyrimidine, Ln = Gd(III, 1; Tb(III, 2; Dy(III, 3; Ho(III, 4 and Er(III, 5 has been synthesized and characterized. Sublimation of [Tb(tmhd3]2bpm onto a Au(111 surface leads to the formation of a homogeneous film with hexagonal pattern, which was studied by scanning tunneling microscopy (STM. The bulk magnetic properties of all complexes have been studied comprehensively. The dynamic magnetic behavior of the Dy(III and Er(III compounds clearly exhibits single molecule magnet (SMM characteristics with an energy barrier of 97 and 25 K, respectively. Moreover, micro-SQUID measurements on single crystals confirm their SMM behavior with the presence of hysteresis loops.

  7. Scaling Behavior and Magnetic Properties for SmxCo5 Films

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    SmxCo5 (x=1.3, 0.7, 0.4) thin films were prepared by magnetron co-sputtering technique. The samples were annealed at 723 K under Ar atmosphere. The annealed time was chosen as 30 min. The hysteresis loops of the samples were measured under the ac applied magnetic field with the period Tp (2π/ω), H(t)=H0sin(ωt), by vibrating sample magnetometer (VSM). The experimental results indicate that, (1) the average hysteresis loop areas as functions of the values of H0 and ω display a power scaling law with the exponents, A=A0+H0αωβ; (2) the x composition of SmxCo5 film has evident effect on the scaling behavior and magnetic properties; (3) the anisotropy scaling exponents exist clearly in the anisotropy SmxCo5 thin films. Moreover, the scaling behavior of the anisotropy magnetic film was also simulated with Monte Carlo method. The simulated results are consistent with the experimental fact.

  8. Chaotic behavior of collective ion dynamics in the presence of an external static magnetic field

    Science.gov (United States)

    Poria, Swarup; Ghosh, Samiran

    2016-06-01

    The two-dimensional nonlinear collective ion dynamics in the presence of external magnetic field in an electron-ion plasma is investigated. The analysis is performed for traveling plane waves to elucidate the various aspects of the phase-space dynamics. The presence of magnetic field makes the dynamics of the nonlinear wave complex with a complicated phase-space behavior. Thus, the nonlinear wave supports a wide class of nonlinear structures viz., single soliton, multi-soliton, periodic, and quasi-periodic oscillations depending on the values of M (Mach number) and Ω (the ratio of ion gyro-frequency to the ion plasma frequency). The computational results predict the chaotic behavior of the nonlinear wave and the transition to chaos takes place when Ω ≳ 0.35 depending on the direction of propagation and the value of M. The amplitude of the wave depends on the obliqueness of the propagation and Mach number, whereas the magnetic field changes the dispersion properties of the wave.

  9. Anomalous behavior of a confined two-dimensional electron within an external magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Rosas, R; Riera R; Marin, J. L. [Universidad de Sonora, Hermosillo, Sonora (Mexico); Leon, H. [Instituto Superior Jose Antonio Echeverria, La Habana (Cuba)

    2001-10-01

    An anomalous diamagnetic behavior of a confined two-dimensional electron within an external magnetic field (perpendicular to the confining plane) is discussed in this letter. Although this finding is consistent with the pioneering work of Robnik, it has not been previously reported. When this effect occurs, the ratio between the typical length of spatial and magnetic confinement is an integer number. This property leads also to a quantization of the magnetic flux across the confining circle. The possible consequences of the peculiar behavior of the electron within such a structure are discussed. [Spanish] Se estudia una posible anomalia en las propiedades diamagneticas de un electron bidimensional confinado en presencia de un campo magnetico externo perpendicular al plano de confinamiento. Aunque los resultados obtenidos son consistentes con el trabajo pionero de Robnik, no han sido reportados anteriormente, a pesar de sus posibles aplicaciones, ya que cuando ocurre, el cociente entre la longitud magnetica y el tamano de la region de confinamiento es un numero entero, propiedad que establece una cuantizacion del flujo magnetico que atraviesa el circulo confinante. Se discuten las posibles consecuencias del comportamiento peculiar del electron en este tipo de estructura.

  10. The thermal behaviors and phase diagrams of the Ising-type endohedral fullerene with magnetic core and diluted magnetic shell (Core@Shell20)

    Science.gov (United States)

    Kantar, Ersin

    2017-08-01

    We have carried out theoretical studies on Ising-type endohedral fullerene (EF) structure with a dopant magnetic atom encaged within the diluted magnetic spherical cage to examine the evolution in magnetic behaviors. We show how the thermal behaviors and phase diagrams of Ising-type EF are affected by diluted surface, crystal field and exchange couplings. We have used to investigate theoretically the effect of Hamiltonian parameters the effective field calculations within Ising model framework. The model Hamiltonian includes nearest neighbor ferromagnetic and antiferromagnetic center-surface (C-S) interaction as well as ferromagnetic surface interaction. We have shown that the system exhibits the first and second order phase transitions as well as tricritical point. In particular, the conditions for the occurrence of these reentrant and double reentrant behaviors are given explicitly.

  11. Magnetic behavior of NiCu nanowire arrays: Compositional, geometry and temperature dependence

    Science.gov (United States)

    Palmero, E. M.; Bran, C.; del Real, R. P.; Magén, C.; Vázquez, M.

    2014-07-01

    Arrays of Ni100-xCux nanowires ranging in composition 0 ≤ x ≤ 75, diameter from 35 to 80 nm, and length from 150 nm to 28 μm have been fabricated by electrochemical co-deposition of Ni and Cu into self-ordered anodic aluminum oxide membranes. As determined by X-ray diffraction and Transmission Electron Microscopy, the crystalline structure shows fcc cubic symmetry with [111] preferred texture and preferential Ni or Cu lattice depending on the composition. Their magnetic properties such as coercivity and squareness have been determined as a function of composition and geometry in a Vibrating Sample Magnetometer in the temperature range from 10 to 290 K for applied magnetic fields parallel and perpendicular to the nanowires axis. Addition of Cu into the NiCu alloy up to 50% enhances both parallel coercivity and squareness. For the higher Cu content, these properties decrease and the magnetization easy axis becomes oriented perpendicular to the wires. In addition, coercivity and squareness increase by decreasing the diameter of nanowires which is ascribed to the increase of shape anisotropy. The temperature dependent measurements reflect a complex behavior of the magnetic anisotropy as a result of energy contributions with different evolution with temperature.

  12. Quantum confinement of Bi2S3 in glass with magnetic behavior

    Directory of Open Access Journals (Sweden)

    Rajendra P. Panmand

    2013-02-01

    Full Text Available The novel Bi2S3 quantum dots (QDs glass nanosystems with unique magnetic properties have been investigated. The monodispersed QDs of size in the range of 3 to 15 nm were grown in the glass matrix. The optical study of these nanosystems clearly demonstrated the size quantization effect resulting in a pronounced band gap variation with QD size. The magnetic properties of the pristine glass and the Bi2S3 QD glass nanosystems were investigated by VSM and SQUID magnetometer. The pristine glass did not show any ferromagnetism while the Bi2S3 glass nanosystems showed significant and reproducible ferromagnetism. We also investigated the effect of the size of Bi2S3 QDs on the magnetic properties. The saturation magnetization for the 15 nm QD glass-nanosystem (124 memu/g was observed to be higher as compared to the 3nm QD glass nanosystem (58.2 memu/g. The SQUID measurement gave the excellent hysteresis up to 300K. Surprisingly, the bulk Bi2S3 powder is diamagnetic in nature but Bi2S3 quantum dots glass nanosystem showed the ferromagnetic behavior for the first time. The investigated novel QD glass-nanosystem may have a potential application in spintronic devices and most importantly, this nanosystem can be fabricated in any usable shape as per the device requirement.

  13. Novel magnetic behavior of Mn-doped ZnO hierarchical hollow spheres

    Energy Technology Data Exchange (ETDEWEB)

    Hao Yaoming; Lou Shiyun; Zhou Shaomin, E-mail: shaominzhou@yahoo.com; Wang Yongqiang; Chen Xiliang; Zhu Gongyu; Yuan Ruijian; Li Ning [Henan University, Key Lab for Special Functional Materials of Ministry of Education (China)

    2012-01-15

    In this study, unique three-dimensional Zn{sub 0.98}Mn{sub 0.02}O hierarchical hollow microspheres (HHMs) with diameters of 5-8 {mu}m have been synthesized by a simple hydrothermal approach. In particular, room-temperature magnetization measurements indicate that novel co-existence of ferromagnetism (FM)/paramagnetism (PM) and only PM behaviors for the as-annealed Zn{sub 0.98}Mn{sub 0.02}O HHMs at 673 and 1,073 K, respectively, in Ar gas atmosphere appear, whereas the as-synthesized ones show merely pure FM. Based on the Photoluminescence and Raman spectra, it is confirmed that the concentrations of oxygen vacancies in Zn{sub 0.98}Mn{sub 0.02}O HHMs were becoming larger and larger with increasing annealing temperature. Corresponding magnetic evolution mechanism is proposed to relate to oxygen vacancies based on annealing processes. This novel magnetic property will enrich our understanding of diluted magnetic semiconductors.

  14. The role of the disk magnetization on the hysteresis behavior of X-ray binaries

    CERN Document Server

    Petrucci, P O; Henri, G; Pelletier, G

    2007-01-01

    We present a framework for understanding the dynamical and spectral properties of X-ray Binaries, where the presence of an organized large scale magnetic field plays a major role. Such a field is threading the whole accretion disk with an amplitude measured by the disk magnetization $\\mu(r,t) =B_z^2/(\\mu_o P_{tot})$, where $P_{tot}$ is the total, gas and radiation, pressure. Below a transition radius $r_J$, a jet emitting disk (the JED) is settled and drives self-collimated non relativistic jets. Beyond $r_J$, no jet is produced despite the presence of the magnetic field and a standard accretion disc (the SAD) is established. The radial distribution of the disk magnetization $\\mu$ adjusts itself to any change of the disk accretion rate $\\dot m$, thereby modifying the transition radius $r_J$. We propose that a SAD-to-JED transition occurs locally, at a given radius, in a SAD when $\\mu=\\mu_{max} \\simeq 1$ while the reverse transition occurs in a JED only when $\\mu=\\mu_{min}\\simeq 0.1$. This bimodal behavior of ...

  15. Magnetic behavior of NiCu nanowire arrays: Compositional, geometry and temperature dependence

    Energy Technology Data Exchange (ETDEWEB)

    Palmero, E. M., E-mail: epalmero@icmm.csic.es; Bran, C.; Real, R. P. del; Vázquez, M. [Institute of Materials Science of Madrid, CSIC, Madrid 28049 (Spain); Magén, C. [Advanced Microscopy Laboratory (LMA), Institute of Nanoscience of Aragón (INA)-ARAID and Department of Condensed Matter Physics, University of Zaragoza, Zaragoza 50018 (Spain)

    2014-07-21

    Arrays of Ni{sub 100−x}Cu{sub x} nanowires ranging in composition 0 ≤ x ≤ 75, diameter from 35 to 80 nm, and length from 150 nm to 28 μm have been fabricated by electrochemical co-deposition of Ni and Cu into self-ordered anodic aluminum oxide membranes. As determined by X-ray diffraction and Transmission Electron Microscopy, the crystalline structure shows fcc cubic symmetry with [111] preferred texture and preferential Ni or Cu lattice depending on the composition. Their magnetic properties such as coercivity and squareness have been determined as a function of composition and geometry in a Vibrating Sample Magnetometer in the temperature range from 10 to 290 K for applied magnetic fields parallel and perpendicular to the nanowires axis. Addition of Cu into the NiCu alloy up to 50% enhances both parallel coercivity and squareness. For the higher Cu content, these properties decrease and the magnetization easy axis becomes oriented perpendicular to the wires. In addition, coercivity and squareness increase by decreasing the diameter of nanowires which is ascribed to the increase of shape anisotropy. The temperature dependent measurements reflect a complex behavior of the magnetic anisotropy as a result of energy contributions with different evolution with temperature.

  16. A nonferrous instrumental joystick device for recording behavioral responses during magnetic resonance imaging and spectroscopy.

    Science.gov (United States)

    Lukas, S E; Dobrosielski, M; Chiu, T M; Woods, B T; Teoh, S K; Mendelson, J H

    1993-12-01

    A nonferrous joystick device was developed to permit subjects to continuously report ethanol-induced alterations in subjective mood states while undergoing a magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) procedure. The device utilizes air pressure (supplied by a small compressor) that is directed to a series of tubes that terminate in a hand-held unit. The hand-held unit easily fits inside the magnet and resembles a standard computer game joystick except that the ends of the air hoses replace the buttons. The control unit contains three pressure transducers, which are triggered when the tubes are occluded by the subject, activating different pens on an event marker located 6 m from the whole body imager. The unit is safe to use inside a 1.5-Tesla magnetic field and does not disrupt the MRI and MRS recording procedures. Subjective reports of ethanol-induced euphoria and intoxication paralleled the MRS detection of ethanol in the brain. This device could prove to be useful in numerous behavioral studies involving whole-body MRI and MRS.

  17. Real-time change detection for countering improvised explosive devices

    Science.gov (United States)

    van de Wouw, Dennis W. J. M.; van Rens, Kris; van Lint, Hugo; Jaspers, Egbert G. T.; de With, Peter H. N.

    2014-03-01

    We explore an automatic real-time change detection system to assist military personnel during transport and surveillance, by detection changes in the environment with respect to a previous operation. Such changes may indicate the presence of Improvised Explosive Devices (IEDs), which can then be bypassed. While driving, images of the scenes are acquired by the camera and stored with their GPS positions. At the same time, the best matching reference image (from a previous patrol) is retrieved and registered to the live image. Next a change mask is generated by differencing the reference and live image, followed by an adaptive thresholding technique. Post-processing steps such as Markov Random Fields, local texture comparisons and change tracking, further improve time- and space-consistency of changes and suppress noise. The resulting changes are visualized as an overlay on the live video content. The system has been extensively tested on 28 videos, containing over 10,000 manually annotated objects. The system is capable of detecting small test objects of 10 cm3 at a range of 40 meters. Although the system shows an acceptable performance in multiple cases, the performance degrades under certain circumstances for which extensions are discussed.

  18. Improvised Hand Injury Treatment Using Traditional Veterinary Medicine in Ethiopia.

    Science.gov (United States)

    Aerts, Raf; November, Eva J J; Rayyan, Maissa

    2017-09-13

    In remote wilderness environments, local people with traditional knowledge of medicinal plants are potentially important first-line health care providers. We present a case of a 31-year-old man who fell off a horse while trekking through a remote mountain landscape in Ethiopia and sustained blunt force trauma to the hand. A local mountain hut keeper examined the patient's hand and used heated leaves of the succulent plant Kalanchoe petitiana to treat a suspected metacarpal fracture. As first responder in a low-resource setting, the hut keeper relied on his traditional knowledge of ethnoveterinary medicine to improvise a treatment for a human injury in a remote mountain environment. Although in this case the outcome of the traditional intervention was positive, our analysis shows that the massage component of the intervention could have led to complications. Conversely, reports from the use of related Kalanchoe species suggest that heated Kalanchoe leaves could be useful in the compression component of traditional care for hand injuries. Validation of traditional remedies and their therapeutic potential are needed if they are to complement wilderness wound care safely and reliably. The documentation and validation of these remedies are urgently needed, as many medicinal plants and indigenous knowledge of how to use these valuable natural resources are being lost. Copyright © 2017 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  19. Improvised explosive devices: pathophysiology, injury profiles and current medical management.

    Science.gov (United States)

    Ramasamy, A; Hill, A M; Clasper, J C

    2009-12-01

    The improvised explosive device (IED), in all its forms, has become the most significant threat to troops operating in Afghanistan and Iraq. These devices range from rudimentary home made explosives to sophisticated weapon systems containing high-grade explosives. Within this broad definition they may be classified as roadside explosives and blast mines, explosive formed pojectile (EFP) devices and suicide bombings. Each of these groups causeinjury through a number of different mechanisms and can result in vastly different injury profiles. The "Global War on Terror" has meant that incidents which were previously exclusively seen in conflict areas, can occur anywhere, and clinicians who are involved in emergency trauma care may be required to manage casualties from similar terrorist attacks. An understanding of the types of devices and their pathophysiological effects is necessary to allow proper planning of mass casualty events and to allow appropriate management of the complex poly-trauma casualties they invariably cause. The aim of this review article is to firstly describe the physics and injury profile from these different devices and secondly to present the current clinical evidence that underpins their medical management.

  20. Simulating magnetic nanoparticle behavior in low-field MRI under transverse rotating fields and imposed fluid flow

    Science.gov (United States)

    Cantillon-Murphy, P.; Wald, L. L.; Adalsteinsson, E.; Zahn, M.

    2010-09-01

    In the presence of alternating-sinusoidal or rotating magnetic fields, magnetic nanoparticles will act to realign their magnetic moment with the applied magnetic field. The realignment is characterized by the nanoparticle's time constant, τ. As the magnetic field frequency is increased, the nanoparticle's magnetic moment lags the applied magnetic field at a constant angle for a given frequency, Ω, in rad s -1. Associated with this misalignment is a power dissipation that increases the bulk magnetic fluid's temperature which has been utilized as a method of magnetic nanoparticle hyperthermia, particularly suited for cancer in low-perfusion tissue (e.g., breast) where temperature increases of between 4 and 7 °C above the ambient in vivo temperature cause tumor hyperthermia. This work examines the rise in the magnetic fluid's temperature in the MRI environment which is characterized by a large DC field, B0. Theoretical analysis and simulation is used to predict the effect of both alternating-sinusoidal and rotating magnetic fields transverse to B0. Results are presented for the expected temperature increase in small tumors ( ˜1 cm radius) over an appropriate range of magnetic fluid concentrations (0.002-0.01 solid volume fraction) and nanoparticle radii (1-10 nm). The results indicate that significant heating can take place, even in low-field MRI systems where magnetic fluid saturation is not significant, with careful the goal of this work is to examine, by means of analysis and simulation, the concept of interactive fluid magnetization using the dynamic behavior of superparamagnetic iron oxide nanoparticle suspensions in the MRI environment. In addition to the usual magnetic fields associated with MRI, a rotating magnetic field is applied transverse to the main B0 field of the MRI. Additional or modified magnetic fields have been previously proposed for hyperthermia and targeted drug delivery within MRI. Analytical predictions and numerical simulations of the

  1. Asymmetric voltage behavior of the tunnel magnetoresistance in double barrier magnetic tunnel junctions

    KAUST Repository

    Useinov, Arthur

    2012-06-01

    In this paper, we study the value of the tunnel magnetoresistance (TMR) as a function of the applied voltage in double barrier magnetic tunnel junctions (DMTJs) with the left and right ferromagnetic (FM) layers being pinned and numerically estimate the possible difference of the TMR curves for negative and positive voltages in the homojunctions (equal barriers and electrodes). DMTJs are modeled as two single barrier junctions connected in series with consecutive tunneling (CST). We investigated the asymmetric voltage behavior of the TMR for the CST in the range of a general theoretical model. Significant asymmetries of the experimental curves, which arise due to different annealing regimes, are mostly explained by different heights of the tunnel barriers and asymmetries of spin polarizations in magnetic layers. © (2012) Trans Tech Publications.

  2. Structural, dielectric and magnetic behavior of nanocrystalline zinc substituted magnesium ferrite

    Energy Technology Data Exchange (ETDEWEB)

    Jyoti,, E-mail: jyotijoshi.phy2008@gmail.com; Parashar, Jyoti; Saxena, V. K.; Dolia, S. N.; Bhatnagar, D. [Department of Physics, University of Rajasthan, Jaipur 302004 (India); Kumar, S. [Department of Physics, Mohan Lal Sukhadia University, Udaipur, Rajasthan (India); Sharma, K. B. [Department of Physics, S. S. Jain Subodh P. G. College, Jaipur (India)

    2015-06-24

    Zinc substituted magnesium ferrites Zn{sub 0.2}Mg{sub 0.8}Fe{sub 2}O{sub 4} and Zn{sub 0.4}Mg{sub 0.6}Fe{sub 2}O{sub 4} were prepared by sol-gel auto combustion method. Rietveld profile refinement of the XRD patterns confirms the formation of a cubic spinel structure in single phase. The dielectric properties viz. dielectric constant and dielectric loss tangent tanδ increase with increasing temperature. The dielectric behavior is explained by using the mechanism of polarization process, which is correlated to that of electron exchange interaction. The saturation magnetization, coercivity and remanent magnetization decreases appreciably with increase in Zn which could be attributed to change in cation distribution.

  3. Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z. X.; Huang, C. J. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR (China); Li, L. F. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, C (China); Li, J. W. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and University of Chinese Academy of Sciences, Beijing 100049, PR (China); Tan, R.; Tu, Y. P. [North China Electric Power University, Beijing 102206, PR (China)

    2014-01-27

    In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical properties of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.

  4. The role of emotion in musical improvisation: an analysis of structural features.

    Science.gov (United States)

    McPherson, Malinda J; Lopez-Gonzalez, Monica; Rankin, Summer K; Limb, Charles J

    2014-01-01

    One of the primary functions of music is to convey emotion, yet how music accomplishes this task remains unclear. For example, simple correlations between mode (major vs. minor) and emotion (happy vs. sad) do not adequately explain the enormous range, subtlety or complexity of musically induced emotions. In this study, we examined the structural features of unconstrained musical improvisations generated by jazz pianists in response to emotional cues. We hypothesized that musicians would not utilize any universal rules to convey emotions, but would instead combine heterogeneous musical elements together in order to depict positive and negative emotions. Our findings demonstrate a lack of simple correspondence between emotions and musical features of spontaneous musical improvisation. While improvisations in response to positive emotional cues were more likely to be in major keys, have faster tempos, faster key press velocities and more staccato notes when compared to negative improvisations, there was a wide distribution for each emotion with components that directly violated these primary associations. The finding that musicians often combine disparate features together in order to convey emotion during improvisation suggests that structural diversity may be an essential feature of the ability of music to express a wide range of emotion.

  5. The role of emotion in musical improvisation: an analysis of structural features.

    Directory of Open Access Journals (Sweden)

    Malinda J McPherson

    Full Text Available One of the primary functions of music is to convey emotion, yet how music accomplishes this task remains unclear. For example, simple correlations between mode (major vs. minor and emotion (happy vs. sad do not adequately explain the enormous range, subtlety or complexity of musically induced emotions. In this study, we examined the structural features of unconstrained musical improvisations generated by jazz pianists in response to emotional cues. We hypothesized that musicians would not utilize any universal rules to convey emotions, but would instead combine heterogeneous musical elements together in order to depict positive and negative emotions. Our findings demonstrate a lack of simple correspondence between emotions and musical features of spontaneous musical improvisation. While improvisations in response to positive emotional cues were more likely to be in major keys, have faster tempos, faster key press velocities and more staccato notes when compared to negative improvisations, there was a wide distribution for each emotion with components that directly violated these primary associations. The finding that musicians often combine disparate features together in order to convey emotion during improvisation suggests that structural diversity may be an essential feature of the ability of music to express a wide range of emotion.

  6. Effect of niobium addition on magnetization reversal behavior for SmCo-based magnets with TbCu7-type structure

    Institute of Scientific and Technical Information of China (English)

    胡晨宇; 泮敏翔; 吴琼; 葛洪良; 王秀敏; 卢阳春; 张朋越

    2016-01-01

    The effect of Nb addition on the microstructure and magnetic properties of nanocrystalline Sm(CobalNbxZr0.02)7 permanent magnet were investigated. The magnetization reversal behavior for ball milled Sm(CobalNbxZr0.02)7 samples with high coercivity was investigated by analyzing hysteresis curves and recoil loops of demagnetization curves. Nb addition proved to result in relevant im-provement in the magnetic properties, especially in the coercivityHc. It was shown that the magnetic properties of Sm(CobalNbx-Zr0.02)7 nanocrystalline magnets were improved by an additional 0.06 at.% Nb. In particular, Hc was improved from 602 to 786 kA/m at room temperature. The maximum value of the integrated recoil loops area for 0.06 at.% Nb-doped samples of 1.81 kJ/m3 was much lower than that of the Nb-free sample, which could be explained by a smaller recoverable portion of the magnetization remaining in the Nb-doped sample when the applied field was below the coercivityHc. The nucleation fieldHn for irreversible magnetization re-versal of the magnetically hard phase were calculated by analyzed in terms of theΔMirev-Hcurve and the Kondorsky model.

  7. Modeling of hysteretic behavior of the levitation force between superconductor and permanent magnet

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Xing-da, E-mail: shuxdw@gmail.com [School of Information Engineering, Guangdong Medical College, No. 2, Eastern Wenming Road, Zhanjiang 524023 (China); Xu, Ke-Xi, E-mail: kxxu@staff.shu.edu.cn [Department of Physics, Shanghai University, Shanghai 200444 (China); Cao, Yue; Hu, Shun-bo; Zuo, Peng-xiang; Li, Guan-dong [Department of Physics, Shanghai University, Shanghai 200444 (China)

    2013-03-15

    Highlights: ► Experimental results on hysteretic behavior of the levitaion force are presented. ► Hysteresis loop for the first descent/ascent cycle of magnet is largest. ► Hysteresis loop for the second and subsequent cycles almost overlap each other. ► Yang’s frozen-image model cannot describe this characteristic of levitation force. ► An updated frozen-image model is developed to describe these experimental results. -- Abstract: The hysteretic behavior of the levitation force between a permanent magnet and a melt-textured-growth YBCO bulk has been investigated under both zero-field cooling (ZFC) and field cooling (FC) processes. It is found that both in ZFC and FC measurements, the hysteresis loop for the first descent/ascent cycle of magnet is relatively larger than that for the second or third cycle, and the hysteresis loops for Cycle 2–4 have the same area. These results can be qualitatively understood in terms of the critical state model. To describe these experimental results, we develop an updated frozen-image model, which is obtained by modifying the change rules of the vertical movement image in the advanced frozen-image model proposed by Yang et al. Comparing with the advanced frozen-image model proposed by Yang et al., our model cannot only give the hysteretic characteristic in the first descent–ascent cycle of magnet, but also show the hysteresis loops with the same area for the second and subsequent cycles.

  8. Freedom and Responsibility: The Aesthetics of Free Musical Improvisation and Its Educational Implications--A View from Bakhtin

    Science.gov (United States)

    Kanellopoulos, Panagiotis A.

    2011-01-01

    This paper aims to examine how specific aspects of Bakhtin's theoretical perspective might inform our understanding of improvisation. Moreover, it outlines the possible educational implications of such a perspective. Specifically, a sketch of a Bakhtinian conception of improvisation is proposed, a sketch which emphasizes the cultivation of an…

  9. Origins and Expertise in the Musical Improvisations of Adults and Children: A Phenomenological Study of Content and Process

    Science.gov (United States)

    Custodero, Lori A.

    2007-01-01

    This study explores the musical content and human processes of improvisations of children and adults using the phenomenological lenses of time, space and responsivity. Paired improvisational performances of two late-career adult composers and two 7-year-old children were analysed considering a lifespan-related perspective involving the origins of…

  10. "Play It Again, Billy, but This Time with More Mistakes": Divergent Improvisation Activities for the Jazz Ensemble

    Science.gov (United States)

    Healy, Daniel J.

    2014-01-01

    The jazz ensemble represents an important performance opportunity in many school music programs. Due to the cultural history of jazz as an improvisatory art form, school jazz ensemble directors must address methods of teaching improvisation concepts to young students. Progress has been made in the field of prescribed improvisation activities and…

  11. Differential parietal and temporal contributions to music perception in improvising and score-dependent musicians, an fMRI study

    NARCIS (Netherlands)

    Harris, Robert; de Jong, Bauke M.

    2015-01-01

    Using fMRI, cerebral activations were studied in 24 classically-trained keyboard performers and 12 musically unskilled control subjects. Two groups of musicians were recruited: improvising (n=12) and score-dependent (non-improvising) musicians (n=12). While listening to both familiar and unfamiliar

  12. Freedom and Responsibility: The Aesthetics of Free Musical Improvisation and Its Educational Implications--A View from Bakhtin

    Science.gov (United States)

    Kanellopoulos, Panagiotis A.

    2011-01-01

    This paper aims to examine how specific aspects of Bakhtin's theoretical perspective might inform our understanding of improvisation. Moreover, it outlines the possible educational implications of such a perspective. Specifically, a sketch of a Bakhtinian conception of improvisation is proposed, a sketch which emphasizes the cultivation of an…

  13. Differential parietal and temporal contributions to music perception in improvising and score-dependent musicians, an fMRI study

    NARCIS (Netherlands)

    Harris, Robert; de Jong, Bauke M.

    2015-01-01

    Using fMRI, cerebral activations were studied in 24 classically-trained keyboard performers and 12 musically unskilled control subjects. Two groups of musicians were recruited: improvising (n=12) and score-dependent (non-improvising) musicians (n=12). While listening to both familiar and unfamiliar

  14. "Play It Again, Billy, but This Time with More Mistakes": Divergent Improvisation Activities for the Jazz Ensemble

    Science.gov (United States)

    Healy, Daniel J.

    2014-01-01

    The jazz ensemble represents an important performance opportunity in many school music programs. Due to the cultural history of jazz as an improvisatory art form, school jazz ensemble directors must address methods of teaching improvisation concepts to young students. Progress has been made in the field of prescribed improvisation activities and…

  15. Critical Behavior of Gaussian Model on X Fractal Lattices in External Magnetic Fields

    Institute of Scientific and Technical Information of China (English)

    LI Ying; KONG Xiang-Mu; HUANG Jia-Yin

    2003-01-01

    Using the renormalization group method, the critical behavior of Gaussian model is studied in external magnetic fields on X fractal lattices embedded in two-dimensional and d-dimensional (d > 2) Euclidean spaces, respectively. Critical points and exponents are calculated. It is found that there is long-range order at finite temperature for this model, and that the critical points do not change with the space dimensionality d (or the fractal dimensionality dr). It is also found that the critical exponents are very different from results of Ising model on the same lattices, and that the exponents on X lattices are different from the exact results on translationally symmetric lattices.

  16. Turning on single-molecule magnet behavior in a linear {Mn3} compound.

    Science.gov (United States)

    Habib, Fatemah; Brunet, Gabriel; Loiseau, Francis; Pathmalingam, Thushan; Burchell, Tara J; Beauchemin, André M; Wernsdorfer, Wolfgang; Clérac, Rodolphe; Murugesu, Muralee

    2013-02-04

    The synthesis, structure, and magnetic properties are reported for a new manganese compound with a mixed-valent {Mn(3)} core arranged in a linear fashion. The previously reported complex 1, [Mn(IV)(3)(dpo)(6)]·2MeCN, where H(2)dpo is (E)-1-hydroxy-1,1-diphenylpropan-2-one oxime, served as a starting point for the isolation of a {Mn(3)} compound with an analogous core arrangement through the reaction of Mn(OAc)(2)·4H(2)O, H(3)oxol ((E)-2,5-dihydroxy-2,5-dimethylhexan-3-one oxime), and NaOH in MeOH and MeCN. By using these reaction conditions, compound 2, Na[Mn(IV)(2)Mn(III)(Hoxol)(6)](n)·MeOH·H(2)O, was successfully isolated revealing a central Mn(III) ion thereby introducing structural and magnetic anisotropy to the system. The structure of 2 reveals linear trinuclear Mn(IV)-Mn(III)-Mn(IV) units connected through Na(+) ions forming a linear one-dimensional coordination polymer. The Jahn-Teller axes of each trinuclear unit are aligned parallel within the same chain and form a 75° angle between the two symmetry related chains. Magnetic susceptibility measurements of 1 and 2 in the temperature range 1.9-300 K reveal that only the reduced compound, 2, is a single-molecule magnet (SMM) largely due to the anisotropy introduced by the Jahn-Teller distortions on the Mn(III) ions, which effectively induce this magnet behavior. Weak antiferromagnetic interactions along the chains through the Na(+) cations lead to a modulation of the intrinsic properties of the Mn(IV)-Mn(III)-Mn(IV) SMMs.

  17. Magnetic field effects on buckling behavior of smart size-dependent graded nanoscale beams

    Science.gov (United States)

    Ebrahimi, Farzad; Reza Barati, Mohammad

    2016-07-01

    In this article, buckling behavior of nonlocal magneto-electro-elastic functionally graded (MEE-FG) beams is investigated based on a higher-order beam model. Material properties of smart nanobeam are supposed to change continuously throughout the thickness based on the power-law model. Eringen's nonlocal elasticity theory is adopted to capture the small size effects. Nonlocal governing equations of MEE-FG nanobeam are obtained employing Hamilton's principle and they are solved using the Navier solution. Numerical results are presented to indicate the effects of magnetic potential, electric voltage, nonlocal parameter and material composition on buckling behavior of MEE-FG nanobeams. Therefore, the present study makes the first attempt in analyzing the buckling responses of higher-order shear deformable (HOSD) MEE-FG nanobeams.

  18. Emotional, motivational and interpersonal responsiveness of children with autism in improvisational music therapy.

    Science.gov (United States)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2009-07-01

    Through behavioural analysis, this study investigated the social-motivational aspects of musical interaction between the child and the therapist in improvisational music therapy by measuring emotional, motivational and interpersonal responsiveness in children with autism during joint engagement episodes. The randomized controlled study (n = 10) employed a single subject comparison design in two different conditions, improvisational music therapy and toy play sessions, and DVD analysis of sessions. Improvisational music therapy produced markedly more and longer events of 'joy', 'emotional synchronicity' and 'initiation of engagement' behaviours in the children than toy play sessions. In response to the therapist's interpersonal demands, 'compliant (positive) responses' were observed more in music therapy than in toy play sessions, and 'no responses' were twice as frequent in toy play sessions as in music therapy. The results of this exploratory study found significant evidence supporting the value of music therapy in promoting social, emotional and motivational development in children with autism.

  19. Emotional, motivational and interpersonal responsiveness of children with autism in improvisational music therapy

    DEFF Research Database (Denmark)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2009-01-01

    Through behavioural analysis, this study investigated the social-motivational aspects of musical interaction between the child and the therapist in improvisational music therapy by measuring emotional, motivational and interpersonal responsiveness in children with autism during joint attention...... episodes. It was a randomized controlled study (n=10) employing a single subject comparison design in two different conditions, improvisational music therapy and toy play sessions and using DVD analysis of sessions.   Improvisational music therapy produced markedly more and longer events of ‘joy...... play sessions than music therapy. The results of this exploratory study found significant evidence supporting the value of music therapy in promoting social, emotional and motivational development in children with autism....

  20. Perception of ‘Back-Channeling’ Nonverbal Feedback in Musical Duo Improvisation

    Science.gov (United States)

    Moran, Nikki; Hadley, Lauren V.; Bader, Maria; Keller, Peter E.

    2015-01-01

    In witnessing face-to-face conversation, observers perceive authentic communication according to the social contingency of nonverbal feedback cues (‘back-channeling’) by non-speaking interactors. The current study investigated the generality of this function by focusing on nonverbal communication in musical improvisation. A perceptual experiment was conducted to test whether observers can reliably identify genuine versus fake (mismatched) duos from musicians’ nonverbal cues, and how this judgement is affected by observers’ musical background and rhythm perception skill. Twenty-four musicians were recruited to perform duo improvisations, which included solo episodes, in two styles: standard jazz (where rhythm is based on a regular pulse) or free improvisation (where rhythm is non-pulsed). The improvisations were recorded using a motion capture system to generate 16 ten-second point-light displays (with audio) of the soloist and the silent non-soloing musician (‘back-channeler’). Sixteen further displays were created by splicing soloists with back-channelers from different duos. Participants (N = 60) with various musical backgrounds were asked to rate the point-light displays as either real or fake. Results indicated that participants were sensitive to the real/fake distinction in the free improvisation condition independently of musical experience. Individual differences in rhythm perception skill did not account for performance in the free condition, but were positively correlated with accuracy in the standard jazz condition. These findings suggest that the perception of back-channeling in free improvisation is not dependent on music-specific skills but is a general ability. The findings invite further study of the links between interpersonal dynamics in conversation and musical interaction. PMID:26086593

  1. Perception of 'Back-Channeling' Nonverbal Feedback in Musical Duo Improvisation.

    Science.gov (United States)

    Moran, Nikki; Hadley, Lauren V; Bader, Maria; Keller, Peter E

    2015-01-01

    In witnessing face-to-face conversation, observers perceive authentic communication according to the social contingency of nonverbal feedback cues ('back-channeling') by non-speaking interactors. The current study investigated the generality of this function by focusing on nonverbal communication in musical improvisation. A perceptual experiment was conducted to test whether observers can reliably identify genuine versus fake (mismatched) duos from musicians' nonverbal cues, and how this judgement is affected by observers' musical background and rhythm perception skill. Twenty-four musicians were recruited to perform duo improvisations, which included solo episodes, in two styles: standard jazz (where rhythm is based on a regular pulse) or free improvisation (where rhythm is non-pulsed). The improvisations were recorded using a motion capture system to generate 16 ten-second point-light displays (with audio) of the soloist and the silent non-soloing musician ('back-channeler'). Sixteen further displays were created by splicing soloists with back-channelers from different duos. Participants (N = 60) with various musical backgrounds were asked to rate the point-light displays as either real or fake. Results indicated that participants were sensitive to the real/fake distinction in the free improvisation condition independently of musical experience. Individual differences in rhythm perception skill did not account for performance in the free condition, but were positively correlated with accuracy in the standard jazz condition. These findings suggest that the perception of back-channeling in free improvisation is not dependent on music-specific skills but is a general ability. The findings invite further study of the links between interpersonal dynamics in conversation and musical interaction.

  2. Perception of 'Back-Channeling' Nonverbal Feedback in Musical Duo Improvisation.

    Directory of Open Access Journals (Sweden)

    Nikki Moran

    Full Text Available In witnessing face-to-face conversation, observers perceive authentic communication according to the social contingency of nonverbal feedback cues ('back-channeling' by non-speaking interactors. The current study investigated the generality of this function by focusing on nonverbal communication in musical improvisation. A perceptual experiment was conducted to test whether observers can reliably identify genuine versus fake (mismatched duos from musicians' nonverbal cues, and how this judgement is affected by observers' musical background and rhythm perception skill. Twenty-four musicians were recruited to perform duo improvisations, which included solo episodes, in two styles: standard jazz (where rhythm is based on a regular pulse or free improvisation (where rhythm is non-pulsed. The improvisations were recorded using a motion capture system to generate 16 ten-second point-light displays (with audio of the soloist and the silent non-soloing musician ('back-channeler'. Sixteen further displays were created by splicing soloists with back-channelers from different duos. Participants (N = 60 with various musical backgrounds were asked to rate the point-light displays as either real or fake. Results indicated that participants were sensitive to the real/fake distinction in the free improvisation condition independently of musical experience. Individual differences in rhythm perception skill did not account for performance in the free condition, but were positively correlated with accuracy in the standard jazz condition. These findings suggest that the perception of back-channeling in free improvisation is not dependent on music-specific skills but is a general ability. The findings invite further study of the links between interpersonal dynamics in conversation and musical interaction.

  3. Magnetic behavior of bulk and fine particles of RCr{sub 2}Si{sub 2}C (R = La, Ce) compounds: possible magnetic ordering from Cr

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, K; Iyer, Kartik K; Sampathkumaran, E V, E-mail: sampath@mailhost.tifr.res.i [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

    2010-07-28

    The magnetic behavior of the quaternary compounds, RCr{sub 2}Si{sub 2}C (R = La, Ce), has been investigated by magnetization (M) and heat-capacity (C) measurements (1.8-300 K) in the bulk polycrystals and nano forms (<1 {mu}m) obtained by high-energy balling. Our finding is that Cr appears to exhibit magnetic ordering of an itinerant type at low temperatures (<20 K) in the bulk form, as inferred from a combined look at all the data. The magnetic ordering gets gradually suppressed with increasing milling time. Evidence for a mixed-valence state of Ce for the bulk form is obtained from the tendency of magnetic susceptibility to exhibit a maximum above 300 K. However, this feature vanishes in the nano form, which exhibits a Curie-Weiss behavior above 200 K as though Ce tends towards trivalency in these fine particles; in addition, there is a weak upturn in C/T below 10 K in the bulk, which becomes very prominent in the milled Ce-based specimens at lower temperatures, as though heavy-fermion behavior gets stronger in smaller particles.

  4. Ab initio calculations for structural, electronic and magnetic behaviors of nitrogenized monolayer graphene decorated with 5d transition metal atoms

    Science.gov (United States)

    Rafique, Muhammad; Shuai, Yong; Xu, Meng; Zhang, Guohua; Guo, Yanming

    2017-09-01

    Graphene-based magnetic materials have revealed great potential for developing high-performance electronic units at sub-nanometer such as spintronic data storage devices. However, a significant ferromagnetism behavior and ample band gap in the electronic structure of graphene is required before it can be used for actual engineering applications. Based on first-principles calculations, here we demonstrate the structural, electronic and magnetic behaviors of 5d transition metal (TM) atom-substituted nitrogenized monolayer graphene. We find that, during TMN(3)4 cluster-substitution, tight bonding occurs between impurity atoms and graphene with significant binding energies. Charge transfer occurs from graphene layer to the TMN(3)4 clusters. Interestingly, PtN3, TaN4 and ReN4 cluster-doped graphene structures exhibit dilute magnetic semiconductor behavior with 1.00 μB, 1.04 μB and 1.05 μB magnetic moments, respectively. While, OsN4 and PtN4 cluster-doped structures display nonmagnetic direct band gap semiconductor behavior. Remaining, TMN(3)4 cluster-doped graphene complexes exhibit half metal properties. Detailed analysis of density of states (DOS) plots indicate that d orbitals of TM atoms should be responsible for arising magnetic moments in graphene. Given results pave a new route for potential applications of dilute magnetic semiconductors and half-metals in spintronic devices by employing TMN(3)4 cluster-doped graphene complexes.

  5. Magnetic behavior of RMn2+xAl10-x (R=La,Gd) crystals

    Science.gov (United States)

    Sefat, Athena S.; Li, Bin; Bud'Ko, Sergey L.; Canfield, Paul C.

    2007-11-01

    The crystallographic and magnetic properties of the solution grown RMn2+xAl10-x ( R=Gd and La) crystals with tetragonal (P4/nmm) structure are investigated. For these, single-crystal x-ray diffraction results have shown the preferential occupation of excess manganese on the aluminum 8i crystallographic site. Due to excess Mn, there is evidence of local-moment magnetism in LaMn2+xAl10-x and their random distribution is thought to be responsible for the magnetic correlations below ˜50K and the spin-glass behavior below ˜3K . For GdMn2+xAl10-x , the extra manganese influences temperature below which the sample enters into a state with a net ferromagnetic component: TC≈16K for GdMn2.21(4)Al9.79(4) and 25.5K for GdMn2.39(2)Al9.61(2) . Assuming a linear dependence between TC and excess Mn concentration, the fully stoichiometric and ordered GdMn2Al10 should have TC≈5K .

  6. Single-molecule magnet behavior for an antiferromagnetically superexchange-coupled dinuclear dysprosium(III) complex.

    Science.gov (United States)

    Long, Jérôme; Habib, Fatemah; Lin, Po-Heng; Korobkov, Ilia; Enright, Gary; Ungur, Liviu; Wernsdorfer, Wolfgang; Chibotaru, Liviu F; Murugesu, Muralee

    2011-04-13

    A family of five dinuclear lanthanide complexes has been synthesized with general formula [Ln(III)(2)(valdien)(2)(NO(3))(2)] where (H(2)valdien = N1,N3-bis(3-methoxysalicylidene)diethylenetriamine) and Ln(III) = Eu(III)1, Gd(III)2, Tb(III)3, Dy(III)4, and Ho(III)5. The magnetic investigations reveal that 4 exhibits single-molecule magnet (SMM) behavior with an anisotropic barrier U(eff) = 76 K. The step-like features in the hysteresis loops observed for 4 reveal an antiferromagnetic exchange coupling between the two dysprosium ions. Ab initio calculations confirm the weak antiferromagnetic interaction with an exchange constant J(Dy-Dy) = -0.21 cm(-1). The observed steps in the hysteresis loops correspond to a weakly coupled system similar to exchange-biased SMMs. The Dy(2) complex is an ideal candidate for the elucidation of slow relaxation of the magnetization mechanism seen in lanthanide systems.

  7. Modeling of hysteretic behavior of the levitation force between superconductor and permanent magnet

    Science.gov (United States)

    Wu, Xing-da; Xu, Ke-Xi; Cao, Yue; Hu, Shun-bo; Zuo, Peng-xiang; Li, Guan-dong

    2013-03-01

    The hysteretic behavior of the levitation force between a permanent magnet and a melt-textured-growth YBCO bulk has been investigated under both zero-field cooling (ZFC) and field cooling (FC) processes. It is found that both in ZFC and FC measurements, the hysteresis loop for the first descent/ascent cycle of magnet is relatively larger than that for the second or third cycle, and the hysteresis loops for Cycle 2-4 have the same area. These results can be qualitatively understood in terms of the critical state model. To describe these experimental results, we develop an updated frozen-image model, which is obtained by modifying the change rules of the vertical movement image in the advanced frozen-image model proposed by Yang et al. Comparing with the advanced frozen-image model proposed by Yang et al., our model cannot only give the hysteretic characteristic in the first descent-ascent cycle of magnet, but also show the hysteresis loops with the same area for the second and subsequent cycles.

  8. Corrosion behaviors of NdFeB magnets prepared by spark plasma sintering

    Institute of Scientific and Technical Information of China (English)

    Tao Li; Ming Yue; Aizhi Sun; Baoqin Qiu; Yaofu Xiao; Jiuxing Zhang

    2004-01-01

    The spark plasma sintering (SPS) technique was introduced into the field of NdFeB preparation due to its own advantages.High property NdFeB magnets with fine grains were prepared by SPS method. The corrosion behaviors of SPS NdFeB were studied by electrochemical measurements and 92% RH hyther tests at 353 K. The results were compared with those of the traditional sintered NdFeB magnets. It shows that both the SPS NdFeB and the traditional sintered NdFeB have good corrosion resistance in alkaline environment due to surface passivation; while, the fine grain microstructure of SPS NdFeB results in a more homogeneous phase composition distribution and thus reduces the electrochemical inhomogenity between the ferromagnetic phase and the Nd-rich intergranular phase in the magnet. Therefore, the SPS NdFeB exhibits better corrosion resistance than the traditional sintered NdFeB in neutral and weak acidic environment.

  9. Monte Carlo study of magnetic behavior of core–shell nanoribbon

    Energy Technology Data Exchange (ETDEWEB)

    Drissi, L.B., E-mail: ldrissi@fsr.ac.ma [Lab-PHE, Modeling and Simulations, Faculty of Science, Mohammed V University, Rabat (Morocco); Zriouel, S. [Lab-PHE, Modeling and Simulations, Faculty of Science, Mohammed V University, Rabat (Morocco); Bahmad, L. [Lab de Magnétisme et PHE, Faculty of Science, Mohammed V University, Rabat (Morocco)

    2015-01-15

    Using Monte Carlo simulations within Ising model, we study the magnetic properties and the hysteresis loops of a core–shell nanoribbon, made of spins σ=1/2 core surrounded by spins S=1 shell with anti-ferromagnetic intermediate coupling. We analyze the ground-state phase diagrams in the presence of external magnetic and crystal fields. We show the existence of the compensation temperature and its dependence on the σ–S and S–S couplings. We investigate the effects of the crystal-field, temperature, shell interactions and intermediate coupling on the hysteresis curves. A number of characteristic behaviors are found, such as the occurrence of single and triple hysteresis loops for appropriate values of the system parameters. The obtained results are in good agreement with available experimental and theoretical works. - Highlights: • We study mixed spin (1/2, 1) core–shell nanoribbon using Monte Carlo calculations. • We show the effects of crystal and magnetic fields on thermodynamic quantities. • We give the conditions for the occurrence of compensation temperature. • We describe the influence of the system's parameters on the hysteresis curves.

  10. Spin Chirality of Cu3 and V3 Nanomagnets. 1. Rotation Behavior of Vector Chirality, Scalar Chirality, and Magnetization in the Rotating Magnetic Field, Magnetochiral Correlations.

    Science.gov (United States)

    Belinsky, Moisey I

    2016-05-02

    The rotation behavior of the vector chirality κ, scalar chirality χ, and magnetization M in the rotating magnetic field H1 is considered for the V3 and Cu3 nanomagnets, in which the Dzialoshinsky-Moriya coupling is active. The polar rotation of the field H1 of the given strength H1 results in the energy spectrum characterized by different vector and scalar chiralities in the ground and excited states. The magnetochiral correlations between the vector and scalar chiralities, energy, and magnetization in the rotating field were considered. Under the uniform polar rotation of the field H1, the ground-state chirality vector κI performs sawtooth oscillations and the magnetization vector MI performs the sawtooth oscillating rotation that is accompanied by the correlated transformation of the scalar chirality χI. This demonstrates the magnetochiral effect of the joint rotation behavior and simultaneous frustrations of the spin chiralities and magnetization in the rotating field, which are governed by the correlation between the chiralities and magnetization.

  11. Corrosion behavior of magnetic refrigeration material La-Fe-Co-Si in distilled water

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Min, E-mail: zhmn9459@gmail.com [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 XueYuan Road, Haidian District, Beijing 100083 (China); Long Yi; Ye Rongchang; Chang Yongqin [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 XueYuan Road, Haidian District, Beijing 100083 (China)

    2011-02-24

    Research highlights: > In this paper, we study the corrosion behavior of La(Fe{sub 0.94}Co{sub 0.06}){sub 11.7}Si{sub 1.3} compound in distilled water and report an unexpected discovery that corrosion occurs at matrix phase rather than rare earth rich phase, which is different from other rare earth materials. The corrosion has decreased the maximum magnetic entropy change of the compound. - Abstract: The corrosion behavior of magnetic refrigeration material La(Fe{sub 0.94}Co{sub 0.06}){sub 11.7}Si{sub 1.3} in distilled water has been studied using X-ray diffraction analysis, weight loss method, scanning electron microscopy and X-ray photoelectron spectroscopy. Results show that La(Fe{sub 0.94}Co{sub 0.06}){sub 11.7}Si{sub 1.3} compound suffers electrochemical preferential corrosion in distilled water. La(Fe{sub 0.94}Co{sub 0.06}){sub 11.7}Si{sub 1.3} compound contains three phases which are matrix phase, a small amount of {alpha}-Fe phase and La-rich phase. The matrix phase with NaZn{sub 13} structure works as anode to be corroded. The final corrosion products on sample surface are La{sub 2}O{sub 3}, {gamma}-Fe(OOH), Co(OH){sub 2} and H{sub 2}SiO{sub 3}, respectively. Corrosion has decreased the maximum magnetic entropy change of the compound.

  12. Synthesis, characterization and magnetic behavior of Co/MCM-41 nano-composites

    Energy Technology Data Exchange (ETDEWEB)

    Cuello, N. [CITeQ-Universidad Tecnológica Nacional-Facultad Regional Córdoba, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba (Argentina); Elías, V. [CITeQ-Universidad Tecnológica Nacional-Facultad Regional Córdoba, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba (Argentina); CONICET (Argentina); Crivello, M. [CITeQ-Universidad Tecnológica Nacional-Facultad Regional Córdoba, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba (Argentina); Oliva, M. [FaMAF-Universidad Nacional de Córdoba, Córdoba (Argentina); IFEG-CONICET (Argentina); Eimer, G., E-mail: geimer@scdt.frc.utn.edu.ar [CITeQ-Universidad Tecnológica Nacional-Facultad Regional Córdoba, Maestro López esq. Cruz Roja Argentina, 5016 Córdoba (Argentina); CONICET (Argentina)

    2013-09-15

    Synthesis, structure and magnetic properties of Co/MCM-41 as magnetic nano-composites have been investigated. Mesoporous materials with different degrees of metal loading were prepared by wet impregnation and characterized by ICP, XRD, N{sub 2} adsorption, UV–vis DRS, TPR and EPMA-EDS. Cobalt oxide clusters and Co{sub 3}O{sub 4} nano-particles could be confined inside the mesopores of MCM-41, being this fact favored by the Co loading increasing. In addition, larger crystals of Co{sub 3}O{sub 4} detectable by XRD also grow on the surface when the Co loading is enhanced. The magnetic characterization was performed in a SQUID magnetometer using a maximum magnetic applied field µ{sub 0}Ha=1 T. While the samples with the higher Co loadings showed a behavior typically paramagnetic, a superparamagnetic contribution is more notorious for lower loadings, suggesting high Co species dispersion. - Graphical abstract: Room temperature hysteresis loops as a function of the Co content. Display Omitted - Highlights: • Co species as isolated Co{sup 2+}, oxide clusters and Co{sub 3}O{sub 4} nano-particles were detected. • For higher Co loads were detected, by XRD, Co{sub 3}O{sub 4} particles on the external surface. • The confining of Co species inside the mesopores was achieved by increasing Co load. • Paramagnetism from oxide clusters/nano-particles becomes dominant for higher Co loads. • Superparamagnetism can be assigned to Co species of small size and finely dispersed.

  13. Same magnetic nanoparticles, different heating behavior: Influence of the arrangement and dispersive medium

    Energy Technology Data Exchange (ETDEWEB)

    Andreu, Irene [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza, Campus Río Ebro, María de Luna, 3, 50018 Zaragoza (Spain); Natividad, Eva, E-mail: evanat@unizar.es [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza, Campus Río Ebro, María de Luna, 3, 50018 Zaragoza (Spain); Solozábal, Laura [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza, Campus Río Ebro, María de Luna, 3, 50018 Zaragoza (Spain); Roubeau, Olivier [Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza, Departamento de Física de la Materia Condensada, 50009 Zaragoza (Spain)

    2015-04-15

    The heating ability of the same magnetic nanoparticles (MNPs) dispersed in different media has been studied in the 170–310 K temperature range. For this purpose, the biggest non-twinned nanoparticles have been selected among a series of magnetite nanoparticles of increasing sizes synthesized via a seeded growth method. The sample with nanoparticles dispersed in n-tetracosane, thermally quenched from 100 °C and solid in the whole measuring range, follows the linear response theoretical behavior for non-interacting nanoparticles, and displays a remarkably large maximum specific absorption rate (SAR) value comparable to that of magnetosomes at the alternating magnetic fields used in the measurements. The other samples, with nanoparticles dispersed either in alkane solvents of sub-ambient melting temperatures or in epoxy resin, display different thermal behaviors and maximum SAR values ranging between 11 and 65% of that achieved for the sample with n-tetracosane as dispersive medium. These results highlight the importance of the MNPs environment and arrangement to maintain optimal SAR values, and may help to understand the disparity sometimes found between MNPs heating performance measured in a ferrofluid and after injection in an animal model, where MNP arrangement and environment are not the same. - Highlights: • We synthetize a series of Fe{sub 3}O{sub 4} nanoparticles by the seeded-growth method. • We characterize the heating ability of 13.9 nm particles dispersed in several media. • We apply SAR(T) characterization to locate the onset of superparamagnetic behavior. • The highest SAR values are obtained in low-concentration solid-alkane dispersion. • Acquired arrangements in different media strongly modify SAR trends and values.

  14. Magnetic field-induced changes of lattice parameters and thermal expansion behavior of the CoMnSi compound

    Energy Technology Data Exchange (ETDEWEB)

    Kou, R. H.; Gao, J.; Wang, G.; Liu, Y. D.; Wang, Y. D.; Ren, Y.; Brown, D. E.

    2016-02-01

    The crystal structure of the CoMnSi compound during zero-field cooling and field cooling from room temperature down to 200 K was studied using the synchrotron radiation X-ray diffraction technique. The results show that the lattice parameters and thermal expansion behavior of the sample are changed by the applied magnetic fields. The lattice contracts along the a axis, but expands along the b and c axes. Due to enlarged and anisotropic changes under a magnetic field of 6 T, the lattice shows an invar-like behavior along all three axes. Critical interatomic distances and bond angles also show large changes under the influence of such a high magnetic field. These magnetic field-induced changes of the lattice are discussed with respect to their contributions to the large magnetocaloric effect of the CoMnSi compound.

  15. Magnetic behavior of Gd3Ru4Al12, a layered compound with distorted kagomé net

    Science.gov (United States)

    Chandragiri, Venkatesh; Iyer, Kartik K.; Sampathkumaran, E. V.

    2016-07-01

    The magnetic behavior of the compound, Gd3Ru4Al12, which was reported about two decades ago to crystallize in a hexagonal structure (space group P63/mmc), has not been investigated in the past literature despite interesting structural features (that is, magnetic layers and triangular as well as kagomé-lattice features favoring frustrated magnetism) characterizing this compound. We report here the results of studies of magnetization, heat capacity and magnetoresistance in the temperature range T  =  1.8-300 K. The results establish that there is a long-range magnetic order of antiferromagnetic type below (T N  =) 18.5 K, despite a much larger value (~80 K) of paramagnetic Curie temperature with a positive sign characteristic of ferromagnetic interaction. We attribute this to geometric frustration. The most interesting finding is that there is an additional magnetic anomaly below ~55 K before the onset of long-range order in the magnetic susceptibility data. Concurrent with this observation, the sign of isothermal change in entropy, ΔS  =  S(0)  -  S(H), where H is the externally applied magnetic field, remains positive above T N, with a broad peak. This observation indicates the presence of ferromagnetic clusters before the onset of long-range magnetic order. Thus, this compound may serve as an example of a situation in which magnetic frustration due to geometrical reasons faces competition from such magnetic precursor effects. There is also a reversal of the sign of  -ΔS in the curves for lower final fields (H  behavior is consistent with the above conclusions.

  16. Dielectric and magnetodielectric behavior of polycrystalline Ca{sub 3}CoRhO{sub 6}, a geometrically frustrated magnetic system

    Energy Technology Data Exchange (ETDEWEB)

    Iyer, Kartik K.; Basu, Tathamay, E-mail: tathamay@tifr.res.in; Singh, Kiran; Sampathkumaran, E. V. [Tata Institute of Fundamental Research, HomiBhabha Road, Colaba, Mumbai-400005 (India)

    2015-06-24

    We have investigated dielectric andmagnetodielectric properties of the geometrically frustrated spin -chain compound Ca{sub 3}CoRhO{sub 6}, which is known to undergo ‘partially disordered antiferromagnetic’ transition around 90 K (T{sub 1}) followed by another glassy magnetic transition around 30 K (T{sub 2}). We have observed dielectric glass behavior around 90 K, at the magnetic transition, which indicates that this behavior is predominantly magnetic in its origin. The magnetic field dependent dielectric constant in the magnetically ordered state tracks the features in isothermal magnetization thereby establishingmagnetodielectric coupling in this compound.

  17. Magnetic behaviors of a transverse spin-1/2 Ising cubic nanowire with core/shell structure

    Science.gov (United States)

    El Hamri, M.; Bouhou, S.; Essaoudi, I.; Ainane, A.; Ahuja, R.; Dujardin, F.

    2017-02-01

    The surface shell exchange coupling effect on the magnetic properties (surface shell, core, total longitudinal and total transverse magnetizations, susceptibility, phase diagram and hysteresis loops) of a transverse spin-1/2 Ising cubic nanowire is investigated, in the present work, by employing the effective-field theory based on the probability distribution technique with correlations, for both ferro- and antiferromagnetic cases. We have found that this parameter has a strong effect on the magnetic properties in both cases. In the ferromagnetic case, the total longitudinal magnetization curves display Q- and S-type behaviors and the hysteresis loop has just one loop, whereas in the antiferromagnetic case, the N-type behavior, in which one compensation temperature appears below the critical temperature, exists in the total longitudinal magnetization curve versus reduced temperature, and triple hysteresis loops are found. The effect of applied field is also investigated on the total longitudinal magnetization for the both cases, and we have found that a large applied field value can overcome the antiferromagnetic coupling leading to a ferromagnetic-like behavior.

  18. COMPARATIVE ANALYSIS OF THE BEHAVIOR OF COAXIAL AND FRONTAL COUPLINGS – WITH PERMANENT MAGNETS – IN HIGH TEMPERATURE ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Marcel Oanca

    2004-12-01

    Full Text Available This paper presents a comparative analysis of the behavior of coaxial and frontal couplings – with permanent magnets – in high temperature environments specific to iron and steel industry. The comparative analysis is made at the level of the specific forces developed in the most difficult environments. The maximum temperature was limited for reasons of thermal stability of the Nd-Fe-B permanent magnets. In this context it was studied, by the help of the PDE-ase soft that uses the finite element method, the way magnetic induction modifies, the specific forces developed and the distribution of temperature within the coaxial and frontal couplers with permanent magnets, for variations of the distance between the magnets (air gap within the limits 2-20 mm.

  19. First-principle investigations of the peculiar magnetic behavior of Sr{sub 2}FeOsO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jing [Key Laboratory of Applied Chemistry, Yanshan University, 066004, Qinhuangdao (China); State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 (China); Zu, Ningning; Wu, Zhijian [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 (China); Hao, Xianfeng; Xu, Yuanhui; Li, Zhiping; Gao, Faming [Key Laboratory of Applied Chemistry, Yanshan University, 066004, Qinhuangdao (China)

    2014-09-15

    Structural, electronic and magnetic properties of Sr{sub 2}FeOsO{sub 6} have been revisited by using the first-principle calculations. Semiconducting behavior is reproduced. The band gap is 0.09 eV from generalized gradient approximation (GGA) and 0.30 eV by considering both SOC and U, a bit larger than the experimental observed 0.125 eV. In the C-type antiferromagnetic configuration, spin frustration is found by analysing the magnetic exchange parameters, explaining the experimental observed magnetic complexity. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. A Review of the Research on Response to Improvised Nuclear Device Events

    Energy Technology Data Exchange (ETDEWEB)

    Bentz, A; Buddemeier, B; Dombroski, M

    2008-07-01

    Following the events of September 11, a litany of imaginable horribles was trotted out before an anxious and concerned public. To date, government agencies and academics are still grappling with how to best respond to such catastrophes, and as Senator Lieberman's quote says above, now is the time to plan and prepare for such events. One of the nation's worst fears is that terrorists might detonate an improvised nuclear device (IND) in an American city. With 9/11 serving as the catalyst, the government and many NGOs have invested money into research and development of response capabilities throughout the country. Yet, there is still much to learn about how to best respond to an IND event. Understanding the state of knowledge, identifying gaps, and making recommendations for how to fill those gaps, this paper will provide a framework under which past findings can be understood and future research can fit. The risk of an improvised nuclear device (IND) detonation may seem unlikely; and while this is hopefully true, due to its destructive capability, IND events must be prepared for. Many people still live under the Cold War mentality that if a city is attacked with a nuclear weapon, there is little chance of survival. This assumption, while perhaps true in the case of multiple, thermonuclear weapons exchanges, does not hold for the current threat. If a single IND were detonated in the United States, there would be many casualties at the point of impact; however, there would also be many survivors and the initial response by two major groups will mean the difference between life and death for many people. These groups are the first responders and the public. Understanding how these two groups prepare, react and interact will improve response to nuclear terrorism. Figure 1 provides a visualization of the response timeline of an IND event. For the purposes of this assessment, it is assumed that to accurately inform the public, three functions need to be

  1. Framework for Reducing Teaching Challenges Relating to Improvisation of Science Education Equipment and Materials in Schools

    Science.gov (United States)

    Akuma, Fru Vitalis; Callaghan, Ronel

    2016-01-01

    The science education budget of many secondary schools has decreased, while shortages and environmental concerns linked to conventional Science Education Equipment and Materials (SEEMs) have emerged. Thus, in some schools, resourceful educators produce low-cost equipment from basic materials and use these so-called improvised SEEMs in practical…

  2. Experimental improvisation practise and notation 1945-1999. An annotated bibliography (2002f). Pdf edition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    Please see also addenda: Experimental improvisation practise and notation. Addenda 2002-: Pdf edition. (Deutsches Resumée - siehe bitte unten) (Resumé en Francais, voire ci-dessous svp.) This is an attempt to make a broad and comprehensive mapping of existing material, the vast majority being...

  3. A Directed Energy System for Defeat of Improvised Explosive Devices and Landmines

    Energy Technology Data Exchange (ETDEWEB)

    Boley, C; Fochs, S; Parker, J; Rotter, M; Rubenchik, A; Yamamoto, R

    2006-03-20

    We describe a laser system, built in our laboratory at LLNL, that has near-term, effective applications in exposing and neutralizing improvised explosive devices and landmines. We discuss experiments with this laser, demonstrating excavation capabilities and relevant material interactions. Model results are also described.

  4. Ground Penetrating Radar: Ultra-wideband radars for improvised explosive devices and landmine detection

    NARCIS (Netherlands)

    Yarovoy, A.

    2008-01-01

    For last two decades Ultra-Wideband Ground Penetrating Radars seemed to be a useful tool for detection and classification of landmines and improvised explosive devices (IEDs). However limitations of radar technology considerably limited operational use of these radars. Recent research at TU Delft so

  5. Ground Penetrating Radar: Ultra-wideband radars for improvised explosive devices and landmine detection

    OpenAIRE

    Yarovoy, A.

    2008-01-01

    For last two decades Ultra-Wideband Ground Penetrating Radars seemed to be a useful tool for detection and classification of landmines and improvised explosive devices (IEDs). However limitations of radar technology considerably limited operational use of these radars. Recent research at TU Delft solves the bottleneck problems.

  6. Graphic Notation as a Tool in Describing and Analyzing Music Therapy Improvisations

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    1993-01-01

    Presents graphic notation as the making of aural scores to memorise or analyse improvised music therapy processes, capturing also those aspectsthe usual music notation would not cover. An example in some detail is shown, the music taken from a well known Nordoff/Robbins recording. Training method...

  7. Improvising in music: A learning biography study to reveal skill acquisition

    NARCIS (Netherlands)

    Wopereis, Iwan; Van Merriënboer, Jeroen; Kirschner, Paul A.

    2010-01-01

    Wopereis, I. G. J. H., Van Merriënboer, J. J. G., & Kirschner, P. A. (2010). Improvising in music: A learning biography study to reveal skill acquisition. In K. Gomez, L. Lyons, & J. Radinsky (Eds.), Proceedings of the 9th International Conference of the Learning Sciences: Vol. 2 (pp. 419-420). Chic

  8. Learning Pre-Played Solos: Self-Regulated Learning Strategies in Jazz/Improvised Music

    Science.gov (United States)

    Nielsen, Siw G.

    2015-01-01

    This article reports on the self-regulated learning strategies of two advanced students in jazz/improvised music education when learning pre-played solos over well-known jazz tunes. The students were enrolled in a well-established performance degree programme in a music conservatoire, and videotaped their own individual practice sessions. In…

  9. Exploring the 12-Key Approach: Perceptions and Experiences of Improvising Jazz Vocalists

    Science.gov (United States)

    Hargreaves, Wendy

    2016-01-01

    The 12-key approach is considered a foundational practice strategy for jazz instrumentalists. Its relevance to vocalists, however, seems less clear. This article investigates improvising jazz vocalists' perceptions and experiences of using the 12-key approach as distinguished from instrumentalists'. It uses data from a two-phase, mixed methods…

  10. Improv(ing) the Academy: Applied Improvisation as a Strategy for Educational Development

    Science.gov (United States)

    Rossing, Jonathan P.; Hoffmann-Longtin, Krista

    2016-01-01

    Improvisational theater training (or "improv") is a strategy employed by many business leaders and educators to cultivate creativity and collaboration amid change. Drawing on improv principles such as "Yes, And…" and "Make your scene partners look good," we explore the ways in which educational developers might apply…

  11. The Instant Composers Pool: Music Notation and the Mediation of Improvising Agency

    NARCIS (Netherlands)

    Schuiling, F.J.

    2016-01-01

    This article relates the recent development of a “relational musicology” to debates about participatory art and relational aesthetics. I present results from an ethnographic study of the Dutch improvising music collective the Instant Composers Pool, founded in 1967 and still performing. With a backg

  12. Oratorium - auditorium - laboratorium: early modern improvisations on cabala, music, and alchemy

    NARCIS (Netherlands)

    Forshaw, P.J.

    2010-01-01

    The article explores the improvisations in the practices of cabala, music and alchemy. It examines the connection between magic, alchemy and cabala and their implications for theosophy according to Paracelsian doctor Heinrich Khunrath. It also analyzes the musical composition and harmony of alchemic

  13. Exploring the 12-Key Approach: Perceptions and Experiences of Improvising Jazz Vocalists

    Science.gov (United States)

    Hargreaves, Wendy

    2016-01-01

    The 12-key approach is considered a foundational practice strategy for jazz instrumentalists. Its relevance to vocalists, however, seems less clear. This article investigates improvising jazz vocalists' perceptions and experiences of using the 12-key approach as distinguished from instrumentalists'. It uses data from a two-phase, mixed methods…

  14. Learning Pre-Played Solos: Self-Regulated Learning Strategies in Jazz/Improvised Music

    Science.gov (United States)

    Nielsen, Siw G.

    2015-01-01

    This article reports on the self-regulated learning strategies of two advanced students in jazz/improvised music education when learning pre-played solos over well-known jazz tunes. The students were enrolled in a well-established performance degree programme in a music conservatoire, and videotaped their own individual practice sessions. In…

  15. Differences between Male and Female Students' Confidence, Anxiety, and Attitude toward Learning Jazz Improvisation

    Science.gov (United States)

    Wehr-Flowers, Erin

    2006-01-01

    The purpose of this study was to examine the gender differences in the social-psychological constructs of confidence, anxiety, and attitude as they relate to jazz improvisation participation. Three subscales of the Fennema-Sherman Mathematics Attitude Survey (1976) were modified for this task, and surveys (N = 332) were given to students of…

  16. Idea Bank: I Can't Do That! Improvisation for Classically Trained Musicians

    Science.gov (United States)

    Buonviri, Nathan

    2013-01-01

    The Partnership for 21st Century Skills lists among its top priorities for students the development of "learning and innovation skills," of which the first are "creativity and innovation." The third National Standard from the National Association for Music Education is "Improvising melodies, variations, and accompaniments." These guiding…

  17. Learning from the Experts: A Study of Free-Improvisation Pedagogues in University Settings

    Science.gov (United States)

    Hickey, Maud

    2015-01-01

    There is a growing interest in alternative forms of pedagogy for students in K-12 settings. Free improvisation, a relatively new and unfamiliar genre, offers potential as an ensemble for teachers to provide in order to offer more egalitarian and creative music experiences for their students. The purpose of this multiple case study was to determine…

  18. Improvising in music: A learning biography study to reveal skill acquisition

    NARCIS (Netherlands)

    Wopereis, Iwan; Van Merriënboer, Jeroen; Kirschner, Paul A.

    2010-01-01

    Wopereis, I. G. J. H., Van Merriënboer, J. J. G., & Kirschner, P. A. (2010). Improvising in music: A learning biography study to reveal skill acquisition. In K. Gomez, L. Lyons, & J. Radinsky (Eds.), Proceedings of the 9th International Conference of the Learning Sciences: Vol. 2 (pp. 419-420). Chic

  19. A Case Study of Diverse Multimodal Influences on Music Improvisation Using Visual Methodology

    Science.gov (United States)

    Tomlinson, Michelle M.

    2016-01-01

    This case study employed multimodal methods and visual analysis to explore how a young multilingual student used music improvisation to form a speech rap. This student, recently arrived in Australia from Ethiopia, created piano music that was central to his music identity and that simultaneously, through dialogue with his mother, enhanced his…

  20. Verbal Auditory Cueing of Improvisational Dance: A Proposed Method for Training Agency in Parkinson's Disease.

    Science.gov (United States)

    Batson, Glenna; Hugenschmidt, Christina E; Soriano, Christina T

    2016-01-01

    Dance is a non-pharmacological intervention that helps maintain functional independence and quality of life in people with Parkinson's disease (PPD). Results from controlled studies on group-delivered dance for people with mild-to-moderate stage Parkinson's have shown statistically and clinically significant improvements in gait, balance, and psychosocial factors. Tested interventions include non-partnered dance forms (ballet and modern dance) and partnered (tango). In all of these dance forms, specific movement patterns initially are learned through repetition and performed in time-to-music. Once the basic steps are mastered, students may be encouraged to improvise on the learned steps as they perform them in rhythm with the music. Here, we summarize a method of teaching improvisational dance that advances previous reported benefits of dance for people with Parkinson's disease (PD). The method relies primarily on improvisational verbal auditory cueing with less emphasis on directed movement instruction. This method builds on the idea that daily living requires flexible, adaptive responses to real-life challenges. In PD, movement disorders not only limit mobility but also impair spontaneity of thought and action. Dance improvisation demands open and immediate interpretation of verbally delivered movement cues, potentially fostering the formation of spontaneous movement strategies. Here, we present an introduction to a proposed method, detailing its methodological specifics, and pointing to future directions. The viewpoint advances an embodied cognitive approach that has eco-validity in helping PPD meet the changing demands of daily living.

  1. Improvisation in the English Primary Music Classroom: Teachers' Perceptions and Practices

    Science.gov (United States)

    Koutsoupidou, Theano

    2005-01-01

    This study investigated teachers' perceptions and practices concerning musical improvisation in the English primary classroom. A questionnaire survey was carried out with participants drawn from primary teachers--both generalists and specialists--working in various regions of England. The findings demonstrate a positive view of teachers'…

  2. “Immunology of music”? A short introduction to cognitive science of musical improvisation

    Directory of Open Access Journals (Sweden)

    Witold Wachowski

    2012-09-01

    Full Text Available Studies on music in the area of cognitive sciences – quite varied despite their short history – meet with scepticism. The author of this introduction, presenting some spectacular examples of research on musical improvisation, tries to demonstrate that they enrich rather than reduce our understanding of this phenomenon.

  3. Experimental improvisation practise and notation 1945-1999. An annotated bibliography (2002f). Pdf edition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    Please see also addenda: Experimental improvisation practise and notation. Addenda 2002-: Pdf edition. (Deutsches Resumée - siehe bitte unten) (Resumé en Francais, voire ci-dessous svp.) This is an attempt to make a broad and comprehensive mapping of existing material, the vast majority being...

  4. Emotional, Motivational and Interpersonal Responsiveness of Children with Autism in Improvisational Music Therapy

    Science.gov (United States)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2009-01-01

    Through behavioural analysis, this study investigated the social-motivational aspects of musical interaction between the child and the therapist in improvisational music therapy by measuring emotional, motivational and interpersonal responsiveness in children with autism during joint engagement episodes. The randomized controlled study (n = 10)…

  5. Emotional, Motivational and Interpersonal Responsiveness of Children with Autism in Improvisational Music Therapy

    Science.gov (United States)

    Kim, Jinah; Wigram, Tony; Gold, Christian

    2009-01-01

    Through behavioural analysis, this study investigated the social-motivational aspects of musical interaction between the child and the therapist in improvisational music therapy by measuring emotional, motivational and interpersonal responsiveness in children with autism during joint engagement episodes. The randomized controlled study (n = 10)…

  6. Remembering to Laugh and Explore: Improvisational Activities for Literacy Teaching in Urban Classrooms

    Science.gov (United States)

    Smith, Katy; McKnight, Katherine S.

    2009-01-01

    In an effort to push back against contextual factors that have constrained arts instruction and integration while recognizing that schools have limited resources, The Second City Training Center in Chicago has developed several educational programs that bring the art of improvisation to teachers and students. This article specifically focuses on…

  7. Common characteristics of improvisational approaches in music therapy for children with autism spectrum disorder

    DEFF Research Database (Denmark)

    Geretsegger, Monika; Holck, Ulla; Carpente, John A.

    2015-01-01

    Background: Improvisational methods of music therapy have been increasingly applied in the treatment of individuals with autism spectrum disorder (ASD) over the past decades in many countries worldwide. Objective: This study aimed at developing treatment guidelines based on the most important...

  8. Feasibility of a Trial on Improvisational Music Therapy for Children with Autism Spectrum Disorder

    DEFF Research Database (Denmark)

    Geretsegger, Monika; Holck, Ulla; Bieleninik, Łucja

    2016-01-01

    and strategies to facilitate study implementation is available in the music therapy literature. Objective: Using data from a subsample of a multi-center RCT on improvisational music therapy (IMT) for autism spectrum disorder (ASD), this study aims to evaluate feasibility of study procedures, evaluate safety...

  9. Common ground: 1970s improvised music as part of a cross-genre Dutch ensemble culture

    NARCIS (Netherlands)

    Rusch, L.

    2011-01-01

    This article focuses on the way in which jazz and Western art music in the Netherlands during the 1970s were intertwined, both social and musically, and how alliances between their avant-gardes (Improvising Musicians and Contemporary Musicians) contributed to what came to be known as Dutch ensemble

  10. Repetitive transcranial magnetic stimulation affects behavior by biasing endogenous cortical oscillations

    Directory of Open Access Journals (Sweden)

    Massihullah Hamidi

    2009-06-01

    Full Text Available A governing assumption about repetitive transcranial magnetic stimulation (rTMS has been that it interferes with task-related neuronal activity – in effect, by “injecting noise” into the brain – and thereby disrupts behavior. Recent reports of rTMS-produced behavioral enhancement, however, call this assumption into question. We investigated the neurophysiological effects of rTMS delivered during the delay period of a visual working memory task by simultaneously recording brain activity with electroencephalography (EEG. Subjects performed visual working memory for locations or for shapes, and in half the trials a 10-Hz train of rTMS was delivered to the superior parietal lobule or a control brain area. The wide range of individual differences in the effects of rTMS on task accuracy, from improvement to impairment, was predicted by individual differences in the effect of rTMS on power in the alpha-band of the EEG (~ 10 Hz: a decrease in alpha-band power corresponded to improved performance, whereas an increase in alpha-band power corresponded to the opposite. The EEG effect was localized to cortical sources encompassing the frontal eye fields and the intraparietal sulcus, and was specific to task (location, but not object memory and to rTMS target (superior parietal lobule, not control area. Furthermore, for the same task condition, rTMS-induced changes in cross-frequency phase synchrony between alpha- and gamma-band (> 40 Hz oscillations predicted changes in behavior. These results suggest that alpha-band oscillations play an active role cognitive processes and do not simply reflect absence of processing. Furthermore, this study shows that the complex effects of rTMS on behavior can result from biasing endogenous patterns of network-level oscillations.

  11. What About Their Performance Do Free Jazz Improvisers Agree Upon? A Case Study.

    Science.gov (United States)

    Pras, Amandine; Schober, Michael F; Spiro, Neta

    2017-01-01

    When musicians improvise freely together-not following any sort of script, predetermined harmonic structure, or "referent"-to what extent do they understand what they are doing in the same way as each other? And to what extent is their understanding privileged relative to outside listeners with similar levels of performing experience in free improvisation? In this exploratory case study, a saxophonist and a pianist of international renown who knew each other's work but who had never performed together before were recorded while improvising freely for 40 min. Immediately afterwards the performers were interviewed separately about the just-completed improvisation, first from memory and then while listening to two 5 min excerpts of the recording in order to prompt specific and detailed commentary. Two commenting listeners from the same performance community (a saxophonist and drummer) listened to, and were interviewed about, these excerpts. Some months later, all four participants rated the extent to which they endorsed 302 statements that had been extracted from the four interviews and anonymized. The findings demonstrate that these free jazz improvisers characterized the improvisation quite differently, selecting different moments to comment about and with little overlap in the content of their characterizations. The performers were not more likely to endorse statements by their performing partner than by a commenting listener from the same performance community, and their patterns of agreement with each other (endorsing or dissenting with statements) across multiple ratings-their interrater reliability as measured with Cohen's kappa-was only moderate, and not consistently higher than their agreement with the commenting listeners. These performers were more likely to endorse statements about performers' thoughts and actions than statements about the music itself, and more likely to endorse evaluatively positive than negative statements. But these kinds of statements

  12. What About Their Performance Do Free Jazz Improvisers Agree Upon? A Case Study

    Directory of Open Access Journals (Sweden)

    Amandine Pras

    2017-06-01

    Full Text Available When musicians improvise freely together—not following any sort of script, predetermined harmonic structure, or “referent”—to what extent do they understand what they are doing in the same way as each other? And to what extent is their understanding privileged relative to outside listeners with similar levels of performing experience in free improvisation? In this exploratory case study, a saxophonist and a pianist of international renown who knew each other's work but who had never performed together before were recorded while improvising freely for 40 min. Immediately afterwards the performers were interviewed separately about the just-completed improvisation, first from memory and then while listening to two 5 min excerpts of the recording in order to prompt specific and detailed commentary. Two commenting listeners from the same performance community (a saxophonist and drummer listened to, and were interviewed about, these excerpts. Some months later, all four participants rated the extent to which they endorsed 302 statements that had been extracted from the four interviews and anonymized. The findings demonstrate that these free jazz improvisers characterized the improvisation quite differently, selecting different moments to comment about and with little overlap in the content of their characterizations. The performers were not more likely to endorse statements by their performing partner than by a commenting listener from the same performance community, and their patterns of agreement with each other (endorsing or dissenting with statements across multiple ratings—their interrater reliability as measured with Cohen's kappa—was only moderate, and not consistently higher than their agreement with the commenting listeners. These performers were more likely to endorse statements about performers' thoughts and actions than statements about the music itself, and more likely to endorse evaluatively positive than negative statements

  13. Repetitive transcranial magnetic stimulation to treat substance use disorders and compulsive behavior.

    Science.gov (United States)

    Protasio, Maria I B; da Silva, João P L; Arias-Carrión, Oscar; Nardi, Antonio E; Machado, Sergio; Cruz, Marcelo S

    2015-01-01

    Compulsions, like pathological gambling, binge-eating disorder, alcohol, tobacco or cocaine abuse and compulsive shopping have similar neurophysiological processing. This study aimed to examine the efficacy of repetitive transcranial magnetic stimulation (rTMS) in improving patient control over compulsive behavior. The rTMS modulatory role in cortical mesolimbic pathways possibly implies improvement of the inhibitory control system and compulsive consumption drive. Thus, craving reduction would be a component for control achievement. Within this context, 17 studies were found. Most studies applied rTMS over the left dorsolateral prefrontal cortex. Craving reduction was observed in 10 studies and was associated with improved control of compulsion in two of them. In one study reduction in consumption was found without reduction in craving. In addition, improvement in decision making was found in one study.

  14. Output voltage calculations in double barrier magnetic tunnel junctions with asymmetric voltage behavior

    KAUST Repository

    Useinov, Arthur

    2011-10-22

    In this paper we study the asymmetric voltage behavior (AVB) of the tunnel magnetoresistance (TMR) for single and double barrier magnetic tunnel junctions (MTJs) in range of a quasi-classical free electron model. Numerical calculations of the TMR-V curves, output voltages and I-V characteristics for negative and positive values of applied voltages were carried out using MTJs with CoFeB/MgO interfaces as an example. Asymmetry of the experimental TMR-V curves is explained by different values of the minority and majority Fermi wave vectors for the left and right sides of the tunnel barrier, which arises due to different annealing regimes. Electron tunneling in DMTJs was simulated in two ways: (i) Coherent tunneling, where the DMTJ is modeled as one tunnel system and (ii) consecutive tunneling, where the DMTJ is modeled by two single barrier junctions connected in series. © 2012 Elsevier B.V. All rights reserved.

  15. Magnetic and dielectric behavior of chromium substituted Co-Mg ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jadoun, Priya, E-mail: priya4jadoun@gmail.com; Jyoti,; Prashant, B. L.; Dolia, S. N.; Bhatnagar, D.; Saxena, V. K. [Department of Physics, University of Rajasthan, Jaipur 302004 (India)

    2016-05-06

    The chromium doped Co-Mg ferrite with composition Co{sub 0.5}Mg{sub 0.5}Cr{sub 0.2}Fe{sub 1.8}O{sub 4} has been synthesized using sol-gel auto combustion method. The crystal structure has been analyzed by X-ray diffraction (XRD) technique. XRD pattern reveals the formation of single phase cubic spinel structure. The magnetic measurements show ferromagnetic behavior at room temperature and large coercivity is observed on cooling down the temperature to 20 K. Dielectric constant (ε’) and dielectric loss tangent (tan δ) have been determined at room temperature as a function of frequency in the frequency range 75 kHz to 80 MHz. The decrease in dielectric constant with increasing frequency attributes to Maxwell Wagner model and conduction mechanism in ferrites.

  16. Preparation, Morphology Transformation and Magnetic Behavior of Co3O4 Nano-Leaves

    Institute of Scientific and Technical Information of China (English)

    MENG Ling-Rong; CHEN Wei-Meng; CHEN Chin-Ping; ZHOU He-Ping; PENG Qing

    2010-01-01

    @@ A series of cubic phase Co3O4 nano-leaves were prepared via a combined approach of solution reaction and calcination.According to x-ray diffraction and electron microscopy,we find that the Co3O4 grain size increases with calcination temperature.This can induce many gaps in the products.M-T and M-H magnetization measurements reveal the typical antiferromagnetic behavior of nano-leaves.The effective moments of the samples prepared at 300,400 and 500℃ are 5.6,5.8 and 5.7μB per formula unit(FU),respectively,larger than the bulk value of 4.14μB/FU.

  17. Simulated structural and magnetic behavior of Mn-Ti intercalated dichalcogenide crystals

    Science.gov (United States)

    Roth, M. W.; Wandling, B.; Kidd, T. E.; Shand, P. M.; Stollenwerk, A.

    2016-05-01

    We present the results of extensive Monte Carlo simulations of intercalated manganese-titanium (Mn-Ti) layered TiS2 crystals. The computational model involves mixtures of Mn and Ti in various percentages placed on a triangular lattice with fixed lattice sites and up to five layers. The range of concentrations of intercalated Mn studied was 5%  ⩽  X Mn  ⩽  33% and for Ti, 0%  ⩽  X Ti  ⩽  15%, where X A denotes the percentage of the total number of lattice sites occupied by species A. The species are allowed to interact spatially through a screened Coulomb potential and magnetically with external and RKKY field terms. Structurally, the pure Mn systems present as disordered at very low densities and evolve through a 2  ×  2 structure (perfect at X Mn  =  25%) up to a \\sqrt{3}   ×  \\sqrt{3} lattice (perfect at X Mn  =  33%), with variations of the two ‘perfect’ lattice structures depending on density. Changes in density for pure Mn systems as well as those intercalated with both Mn and Ti dramatically affects the system’s structural and magnetic properties, and the magnetic behavior of various morphological features present in the system are discussed. The RKKY interaction is adjusted based on the intercalant compositions and is very sensitive to structural variations in the intercalant layers. The composition ranges studied here encompass and exceed those that are experimentally accessible, which helps place experimentally relevant densities in perspective.

  18. Nonequilibrium critical behavior of magnetic thin films grown in a temperature gradient

    Science.gov (United States)

    Candia, Julián; Albano, Ezequiel V.

    2012-08-01

    We investigate the irreversible growth of (2 + 1)-dimensional magnetic thin films under the influence of a transverse temperature gradient, which is maintained by thermal baths across a direction perpendicular to the direction of growth. Therefore, different longitudinal layers grow at different temperatures between T1 and T2, where {T}_{1}\\lt {T}_{{c}}^{{hom}}\\lt {T}_{2} and {T}_{{c}}^{{hom}}=0.6 9(1) is the critical temperature of films grown in homogeneous thermal baths. We find a far-from-equilibrium continuous order-disorder phase transition driven by the thermal bath gradient. We characterize this gradient-induced critical behavior by means of standard finite-size scaling procedures, which lead to the critical temperature Tc = 0.84(2) and a new universality class consistent with the set of critical exponents ν = 3/2, γ = 5/2, and β = 1/4. In order to gain further insight into the effects of the temperature gradient, we also develop a bond model that captures the magnetic film’s growth dynamics. Our findings show that the interplay of geometry and thermal bath asymmetries leads to growth bond flux asymmetries and the onset of transverse ordering effects that explain qualitatively the shift observed in the critical temperature. The relevance of these mechanisms is further confirmed by a finite-size scaling analysis of the interface width, which shows that the growing sites of the system define a self-affine interface.

  19. Magnetic and Electrical Behavior of MnTe1-xSbx Alloys

    Institute of Scientific and Technical Information of China (English)

    X. He; Y.Q. Zhang; Z.D. Zhang

    2011-01-01

    The structure, specific heat, magnetic and electrical properties of MnTe1-xSbx (x=0, 0.1, 0.15, 0.2 and 0.25) alloys have been investigated. The MnTe1-xSbx alloys crystallize in a hexagonal NiAs-type structure, and the impurity of MnSb phase appears when :x≥0.15. The MnTe0.9Sb0.1 compound exhibits ferrimagnetic behavior with hysteresis loops even at 350 K, showing that the magnetic properties of MnTe compound are very sensitive to little compositional change. The ferromagnetism in the MnTe1-xSbx alloys with higher Sb contents may be attributed to the impurity of MnSb phase. Energy dispersive X-ray spectroscopy analysis on the MnTe0.9Sb0.1 compound indicates that Sb is very difficult to dope into the lattice of MnTe. So the anomaly of resistivity at 300 K of MnTe0.9Sb0.1 and the peak of specific heat around 304 K of all the alloys are thought to be related with the antiferromagnetic interactions of MnTe-based lattice.

  20. High-temperature annealing effects on multiwalled carbon nanotubes: electronic structure, field emission and magnetic behaviors.

    Science.gov (United States)

    Ray, Sekhar Chandra; Pao, Chih-Wen; Tsai, Huang-Ming; Chen, Huang-Chin; Chen, Yu-Shin; Wu, Shang-Lun; Ling, Dah-Chin; Lin, I-Nan; Pong, Way-Faung; Gupta, Sanju; Giorcelli, Mauro; Bianco, Stefano; Musso, Simone; Tagliaferro, Alberto

    2009-12-01

    This work elucidates the effects of high-temperature annealing on the microscopic and electronic structure of multiwalled carbon nanotubes (MWCNTs) using high-resolution transmission electron microscopy, micro-Raman spectroscopy, X-ray diffraction, X-ray absorption near-edge structure (XANES) and valence-band photoemission spectroscopy (VBPES), respectively. The field emission and magnetization behaviors are also presented. The results of annealing are as follows: (1) MWCNTs tend to align in the form of small fringes along their length, promote graphitization and be stable in air, (2) XANES indicates an enhancement in oxygen content on the sample, implying that it can be adopted for sensing and storing oxygen gas, (3) the electron field emission current density (J) is enhanced and the turn-on electric field (E(TOE)) reduced, suggesting potential use in field emission displays and as electron sources in microwave tube amplifiers and (4) as-grown MWCNTs with embedded iron nanoparticles exhibits significantly higher coercivity approximately 750 Oe than its bulk counterpart (Fe(bulk) approximately 0.9 Oe), suggesting its potential use as low-dimensional high-density magnetic recording media.

  1. Scaling behavior of the dipole-coupling energy in two-dimensional disordered magnetic nanostructures

    Science.gov (United States)

    Jensen, P. J.; Pastor, G. M.

    2003-11-01

    Numerical calculations of the average dipole-coupling energy Edip in two-dimensional disordered magnetic nanostructures are performed as a function of the particle coverage C. We observe that Edip scales as Edip∝Cα* with an unusually small exponent α*≃0.8 1.0 for coverages C≲20%. This behavior is shown to be primarily given by the contributions of particle pairs at short distances, which is intrinsically related to the presence of an appreciable degree of disorder. The value of α* is found to be sensitive to the magnetic arrangement within the nanostructure and to the degree of disorder. For large coverages C≳20% we obtain Edip∝Cα with α=3/2, in agreement with the straightforward scaling of the dipole coupling as in a periodic particle setup. Taking into account the effect of single-particle anisotropies, we show that the scaling exponent can be used as a criterion to distinguish between weakly interacting (α*≃1.0) and strongly interacting (α*≃0.8) particle ensembles as a function of coverage.

  2. Does improvised waterbed reduce the incidence of pressure ulcers in patients with spinal injury?

    Directory of Open Access Journals (Sweden)

    Jude-Kennedy C Emejulu

    2015-01-01

    Full Text Available Background: Pressure ulcers are lesions caused by unrelieved pressure over bony prominences, resulting in damage to underlying tissues. The etiology is multifactorial including prolonged immobility. They usually complicate spinal cord injuries with long periods of bed confinement. The use of bed replacements markedly reduces the incidence of pressure ulcers, but the unaffordability of these replacements in low-income countries has necessitated the need to explore cheaper alternatives. Aim and Objective: The aim of this study was to ascertain whether the use of our cheap and locally improvised waterbeds would reduce the incidence of pressure ulcers in patients on prolonged bed confinement due to spinal injury. Methodology: Over a 16-month period, 51 patients (age range 1-80 years with spinal injuries were managed conservatively in our service using improvised waterbeds in 21 (41.2%, while using the regular hospital bed/foam in 30 (58.8%. Biodata, the time interval between injury and presentation to the hospital, nature of the injury, use of improvised waterbed and development of pressure ulcer, were collected, collated, and analyzed. Statistical significance was calculated with the Chi-square test. Results: Most were males (98%, in the age range of 21-30 years (25.5%, and due to fall from heights (35.3%. Of 21 patients who were managed on improvised waterbeds, 6 (28.6% had pressure ulcers, and of the 30 who did not use the waterbed, 17 (56.7% developed ulcers. The c2 = 3.9381, while P = 0.0472. This difference was statistically significant. Conclusion: The improvised waterbed, which is much cheaper than the standard waterbed, was observed to have significantly reduced the incidence of pressure ulcers among our patients. Nonetheless, further studies would still be needed to confirm this observation.

  3. A study on Improvisation in a Musical performance using Multifractal Detrended Cross Correlation Analysis

    Science.gov (United States)

    Sanyal, Shankha; Banerjee, Archi; Patranabis, Anirban; Banerjee, Kaushik; Sengupta, Ranjan; Ghosh, Dipak

    2016-11-01

    MFDFA (the most rigorous technique to assess multifractality) was performed on four Hindustani music samples played on same 'raga' sung by the same performer. Each music sample was divided into six parts and 'multifractal spectral width' was determined for each part corresponding to the four samples. The results obtained reveal that different parts of all the four sound signals possess spectral width of widely varying values. This gives a cue of the so called 'musical improvisation' in all music samples, keeping in mind they belong to the bandish part of the same raga. Formal compositions in Hindustani raga are juxtaposed with the improvised portions, where an artist manoeuvers his/her own creativity to bring out a mood that is specific for that particular performance, which is known as 'improvisation'. Further, this observation hints at the association of different emotions even in the same bandish of the same raga performed by the same artist, this interesting observation cannot be revealed unless rigorous non-linear technique explores the nature of musical structure. In the second part, we applied MFDXA technique to explore more in-depth about 'improvisation' and association with emotion. This technique is applied to find the degree of cross-correlation (γx) between the different parts of the samples. Pronounced correlation has been observed in the middle parts of the all the four samples evident from higher values of γx ​whereas the other parts show weak correlation. This gets further support from the values of spectral width from different parts of the sample - width of those parts is significantly different from other parts. This observation is extremely new both in respect of musical structure of so called improvisation and associated emotion. The importance of this study in application area of cognitive music therapy is immense.

  4. Structure, magnetism, and theoretical study of a mixed-valence Co(II)3Co(III)4 heptanuclear wheel: lack of SMM behavior despite negative magnetic anisotropy.

    Science.gov (United States)

    Chibotaru, Liviu F; Ungur, Liviu; Aronica, Christophe; Elmoll, Hani; Pilet, Guillaume; Luneau, Dominique

    2008-09-17

    the two marginal Co(II) sites. The lack of single-molecule magnet behavior in [Co(II)3Co(III)4(L)6(MeO)6] is explained by relatively large matrix elements of transverse magnetic moments between states of maximal magnetization of the ground Kramers doublet, evidenced by ab initio calculations, and the associated large tunneling rates between these states in the presence of dipolar transverse magnetic fields in the crystal.

  5. Dia-magnetic to ferro-magnetic behavioral change of Fe-catalysts based nitrogenated carbon nanotubes (NCNTs) by the process of chlorination/oxidation.

    Science.gov (United States)

    Ray, S C; Sahu, D R; Papakonstantinou, P

    2011-09-01

    In this work, we have synthesized multiwall nitrogenated carbon nanotubes (MW-NCNTs) with Fe-catalysts by the microwave plasma-enhanced chemical vapor deposition process @950 degrees C and subsequently functionalized with chlorine and oxygen. The dia-magnetic behavioral M-H loop of non-functionalized MW-NCNTs were turn into ferromagnetic behaviors by the process of chlorination and oxidation respectively; which were characterized by means of superconducting quantum interference device magnetometer within the temperature range 5-300 K. A prominent cusp like behavior is also observed at around approximately 45 K in M(FC) and M(ZFC) measurements confirming the ferromagnetic behaviors of these MW-NCNTs after chlorination and oxidation.

  6. Magnetic behavior of metallic kagome lattices, Tb3Ru4Al12 and Er3Ru4Al12

    Science.gov (United States)

    Upadhyay, Sanjay Kumar; Iyer, Kartik K.; Sampathkumaran, E. V.

    2017-08-01

    We report the magnetic behavior of two intermetallic-based kagome lattices, Tb3Ru4Al12 and Er3Ru4Al12, crystallizing in the Gd3Ru4Al2-type hexagonal crystal structure, by measurements in the range 1.8-300 K with bulk experimental techniques (ac and dc magnetization, heat capacity, and magnetoresistance). The main finding is that the Tb compound, known to order antiferromagnetically below (T N =) 22 K, shows glassy characteristics at lower temperatures (\\ll 15 K), thus characterizing this compound as a re-entrant spin-glass. The data reveal that the glassy phase is quite complex and is of a cluster type. Since glassy behavior was not seen for the Gd analog in the past literature, this finding on the Tb compound emphasizes that this kagome family could provide an opportunity to explore the role of higher-order interactions (such as quadrupole) in bringing out magnetic frustration. Additional findings reported here for this compound are: (i) The plots of temperature dependence of magnetic susceptibility and electrical resistivity data in the range 12-20 K, just below T N , are found to be hysteretic leading to a magnetic phase in this intermediate temperature range, mimicking disorder-broadened first-order magnetic phase transitions; (ii) features attributable to an interesting magnetic phase co-existence phenomenon in the isothermal magnetoresistance in zero field, after travelling across metamagnetic transition fields, are observed. With respect to the Er compound, we do not find any evidence for long-range magnetic ordering down to 2 K, but this compound appears to be on the verge of magnetic order at 2 K.

  7. Benzoxazole-based heterometallic dodecanuclear complex [Dy(III)4Cu(II)8] with single-molecule-magnet behavior.

    Science.gov (United States)

    Iasco, Olga; Novitchi, Ghenadie; Jeanneau, Erwann; Wernsdorfer, Wolfgang; Luneau, Dominique

    2011-08-15

    Three Cu-Ln (Ln = Dy, Gd, Y) dodecanuclear clusters assembled by a novel ligand of the benzoxazole type are reported. The dysprosium cluster exhibits a frequency dependence of the alternating-current susceptibility and hysteresis loop at low temperature, indicating single-molecule-magnet behavior.

  8. A magnetic-dependent protein corona of tailor-made superparamagnetic iron oxides alters their biological behaviors

    Science.gov (United States)

    Liu, Ziyao; Zhan, Xiaohui; Yang, Minggang; Yang, Qi; Xu, Xianghui; Lan, Fang; Wu, Yao; Gu, Zhongwei

    2016-03-01

    In recent years, it is becoming increasingly evident that once nanoparticles come into contact with biological fluids, a protein corona surely forms and critically affects the biological behaviors of nanoparticles. Herein, we investigate whether the formation of protein corona on the surface of superparamagnetic iron oxides (SPIOs) is influenced by static magnetic field. Under static magnetic field, there is no obvious variation in the total amount of protein adsorption, but the proportion of adsorbed proteins significantly changes. Noticeably, certain proteins including apolipoproteins, complement system proteins and acute phase proteins, increase in the protein corona of SPIOs in the magnetic field. More importantly, the magnetic-dependent protein corona of SPIOs enhances the cellular uptake of SPIOs into the normal cell line (3T3 cells) and tumor cell line (HepG2 cells), due to increased adsorption of apolipoprotein. In addition, SPIOs with the magnetic-dependent protein corona cause high cytotoxicity to 3T3 cells and HepG2 cells. This work discloses that superparamagnetism as a key feature of SPIOs affects the composition of protein corona to a large extent, which further alters the biological behaviors of SPIOs.In recent years, it is becoming increasingly evident that once nanoparticles come into contact with biological fluids, a protein corona surely forms and critically affects the biological behaviors of nanoparticles. Herein, we investigate whether the formation of protein corona on the surface of superparamagnetic iron oxides (SPIOs) is influenced by static magnetic field. Under static magnetic field, there is no obvious variation in the total amount of protein adsorption, but the proportion of adsorbed proteins significantly changes. Noticeably, certain proteins including apolipoproteins, complement system proteins and acute phase proteins, increase in the protein corona of SPIOs in the magnetic field. More importantly, the magnetic-dependent protein

  9. 永磁操动机构磁场计算及动特性分析%Magnetic fieldcal culation and dynamic behavior analyses of permanent magnetic actuator

    Institute of Scientific and Technical Information of China (English)

    高会军; 林莘; 蔡志远

    2000-01-01

    It spresent the magnetic field and dynamic behavior analyses for the permanent magnetic actuator. Finite element method associated to parametrization is calculate the displacement of the moving parts and the supplying current when the actuator is DC voltage supplied or capacitor supplied.In this analysis,the magnetic,electric and mechanical phenomena are coupled and some curves reflecting the ynamic behavior obtained.In addition,the comparison of dynamic behavior between DC voltage supplied and capacitor discharge supplied is drawn.%在建立永磁操动机构动态分析数学模型的基础上,采用有限元分析方法对永磁操动机构激磁后的动态特性进行计算,得出了动铁芯运动过程中的机构磁场分布,线圈电流、动铁芯的位移、运动速度及在运动中受力随时间变化的规律,并比较了在两种不同激磁方式下的机构运动特性及电压大小对永磁操动机构运动特性的影响。

  10. Ocular injuries in survivors of improvised explosive devices (IED in commuter trains

    Directory of Open Access Journals (Sweden)

    Agarwal Vinay

    2007-09-01

    Full Text Available Abstract Background Ocular injuries are common in survivors of terror incidents that involve the use of explosive materials. These explosives are commonly of a High Explosive type (HE and may be fashioned into improvised explosive devices (IED that incorporate additional materials to maximise trauma and injuries. Serial IED explosions have occurred in commuter trains in several cities including London and Madrid but data on ocular injuries is limited. We report the ocular injuries of the survivors of a series of IED explosions in crowded commuter trains. Methods 28 patients (56 eyes, 28 male, ages ranging from 22 to 52 years (mean 35.27 years were screened in the triage area or the Intensive Care Unit (ICU. Testing included bedside visual acuity testing, torchlight examination of the anterior segment and dilated (or if necessary, undilated fundus examination. Selected patients underwent B-scan examination, magnetic resonance imaging of the brain, orbits and the optic nerves or visual evoked potential assessment. The injuries, investigations and procedures were entered into the patient's case sheet as well as into a standardised format suggested by the Indian eye injury registry (IER. Results 16 of 28 patients (57.1% had ocular injuries whereas 12 (42.8% were found to be normal. Injuries were seen unilaterally in 10 patients and bilaterally in six yielding a total of 22 injured eyes. The common injuries were periorbital haemorrhages (09 eyes, 40%; first or second degree burns to the upper or lower lids (seen in 07 eyes, 31.8 % and corneal injuries (seen in 08 eyes, 36.3%. Open globe injuries were seen in two eyes of two patients (09%. One patient (4.5% had a traumatic optic neuropathy. Conclusion Ophthalmologists and traumatologists should be aware of these patterns of ocular injuries. Protocols need to include the screening of large numbers of patients in a short time, diagnostic tests (B scan, visual evoked potential (VEP etc and early surgery

  11. Microstructure and magnetic behavior of Cu-Co-Si ternary alloy synthesized by mechanical alloying and isothermal annealing

    Science.gov (United States)

    Chabri, Sumit; Bera, S.; Mondal, B. N.; Basumallick, A.; Chattopadhyay, P. P.

    2017-03-01

    Microstructure and magnetic behavior of nanocrystalline 50Cu-40Co-10Si (at%) alloy prepared by mechanical alloying and subsequent isothermal annealing in the temperature range of 450-650 °C have been studied. Phase evolution during mechanical alloying and isothermal annealing is characterized by X-ray diffraction (XRD), differential thermal analyzer (DTA), high resolution transmission electron microscopy (HRTEM) and magnetic measurement. Addition of Si has been found to facilitate the metastable alloying of Co in Cu resulting into the formation of single phase solid solution having average grain size of 9 nm after ball milling for 50 h duration. Annealing of the ball milled alloy improves the magnetic properties significantly and best combination of magnetic properties has been obtained after annealing at 550 °C for 1 h duration.

  12. Magnetic Behavior of Some Rare-Earth Transition-Metal Perovskite Oxide Systems

    Institute of Scientific and Technical Information of China (English)

    Kenji Yoshii; Akio Nakamura; Masaichiro Mizumaki; Naoshi Ikeda; Jun'ichiro Mizuki

    2004-01-01

    Magnetic properties were investigated for the rare-earth 3d-transition metal oxides with the perovskite structure. Intriguing magnetic phenomena were reviewed for a few systems:magnetization peak effect in the titanates, magnetization reversal in the chromites and metallic ferromagnetism in the cobaltites. The results suggest an important role of the rare-earth ions for the magnetic properties of such complex oxides.

  13. Magnetic Particle Spectroscopy Reveals Dynamic Changes in the Magnetic Behavior of Very Small Superparamagnetic Iron Oxide Nanoparticles During Cellular Uptake and Enables Determination of Cell-Labeling Efficacy.

    Science.gov (United States)

    Poller, Wolfram C; Löwa, Norbert; Wiekhorst, Frank; Taupitz, Matthias; Wagner, Susanne; Möller, Konstantin; Baumann, Gert; Stangl, Verena; Trahms, Lutz; Ludwig, Antje

    2016-02-01

    In vivo tracking of nanoparticle-labeled cells by magnetic resonance imaging (MRI) crucially depends on accurate determination of cell-labeling efficacy prior to transplantation. Here, we analyzed the feasibility and accuracy of magnetic particle spectroscopy (MPS) for estimation of cell-labeling efficacy in living THP-1 cells incubated with very small superparamagnetic iron oxide nanoparticles (VSOP). Cell viability and proliferation capacity were not affected by the MPS measurement procedure. In VSOP samples without cell contact, MPS enabled highly accurate quantification. In contrast, MPS constantly overestimated the amount of cell associated and internalized VSOP. Analyses of the MPS spectrum shape expressed as harmonic ratio A₅/A₃ revealed distinct changes in the magnetic behavior of VSOP in response to cellular uptake. These changes were proportional to the deviation between MPS and actual iron amount, therefore allowing for adjusted iron quantification. Transmission electron microscopy provided visual evidence that changes in the magnetic properties correlated with cell surface interaction of VSOP as well as with alterations of particle structure and arrangement during the phagocytic process. Altogether, A₅/A₃-adjusted MPS enables highly accurate, cell-preserving VSOP quantification and furthermore provides information on the magnetic characteristics of internalized VSOP.

  14. Magnetic and 57Fe Mössbauer study of the single molecule magnet behavior of a Dy3Fe7 coordination cluster.

    Science.gov (United States)

    Abbas, Ghulam; Lan, Yanhua; Mereacre, Valeriu; Wernsdorfer, Wolfgang; Clérac, Rodolphe; Buth, Gernot; Sougrati, Moulay T; Grandjean, Fernande; Long, Gary J; Anson, Christopher E; Powell, Annie K

    2009-10-05

    The reaction between N-methydiethanolamine (mdeaH(2)), benzoic acid, FeCl(3), and DyCl(3) yields a decanuclear coordination cluster, [Dy(3)Fe(7)(mu(4)-O)(2)(mu(3)-OH)(2)(mdea)(7)(mu-benzoate)(4)(N(3))(6)] x 2 H(2)O x 7 CH(3)OH (1) whose single crystal structure exhibits three and seven crystallographically distinct Dy(III) and Fe(III) ions; six of the Fe(III) ions are pseudo-octahedrally coordinated, whereas the seventh has a trigonal-bipyramidal coordination geometry. Both direct current (dc) and alternating current (ac) magnetic susceptibility studies indicate that, upon cooling, intracluster antiferromagnetic interactions are dominant in 1, yielding a ferrimagnetic spin arrangement. The out-of-phase (chi'') ac susceptibility reveals that 1 undergoes a slow relaxation of its magnetization mainly resulting from the anisotropy of the Dy(III) ions. This slow relaxation has been confirmed both by magnetization measurements on an oriented single crystal of 1 and by the observation of hysteresis loops below 1.9 K. The macroscopic magnetic studies yield an effective energy barrier, U(eff), of 33.4 K for this relaxation, a barrier that is the highest yet reported for a lanthanide(III)-Fe(III) single molecule magnet. The (57)Fe Mössbauer spectra of 1 obtained between 3 and 35 K are consistent with the presence of Fe(III) intracluster antiferromagnetic coupling with slow magnetic relaxation relative to the Larmor precession time, thus confirming, on a microscopic scale, the presence of a barrier to the magnetic relaxation below 35 K. Between 55 and 295 K the Mössbauer spectra reveal paramagnetic behavior with six partially resolved quadrupole doublets, one for the trigonal-bipyramidal Fe(III) site and five for the six pseudo-octahedral Fe(III) sites.

  15. Removal of humic acid from aqueous solution by magnetically separable polyaniline: adsorption behavior and mechanism.

    Science.gov (United States)

    Wang, Jiahong; Bi, Lijuan; Ji, Yanfen; Ma, Hongrui; Yin, Xiaolong

    2014-09-15

    Magnetically separable polyaniline (Fe3O4@SiO2-PANI) was prepared by in situ chemical polymerization of aniline on the surface of silica-coated Fe3O4 nanoparticles, and characterized by FTIR spectroscopy, powder X-ray diffraction, elemental analysis, transmission electron microscopy, vibrating sample magnetometry and X-ray photoelectron spectroscopy. Characterization results showed that Fe3O4@SiO2-PANI with amino groups of 1.78 mmol/g and the average diameter of 21.6 nm are superparamagnetic. Adsorption behavior of Fe3O4@SiO2-PANI nanoparticles for humic acid (HA) was investigated by batch experiments and adsorption kinetic tests. HA adsorption amount on the adsorbent decreased with increasing solution pH and the presence of Ca(2+) resulted in the enhanced HA adsorption. HA adsorption on Fe3O4@SiO2-PANI could be well described by Langmuir model and the maximum adsorption amount of the adsorbent for HA at 25°C was 36.36 mg/g. HA adsorption process on the adsorbent obey pseudo-second-order kinetics and the adsorption rates decrease with increasing initial HA concentration. The XPS analysis verified that HA adsorption over the adsorbent could be attributed to the surface complexation between the disassociated HA molecules and the protonated nitrogen of polyaniline on the adsorbent. HA loaded adsorbent could be magnetically separated and easily desorbed in 0.01 mol/L NaOH solution. Regeneration tests indicated that Fe3O4@SiO2-PANI could be used repeatedly. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Diverse Ligand-Functionalized Mixed-Valent Hexamanganese Sandwiched Silicotungstates with Single-Molecule Magnet Behavior.

    Science.gov (United States)

    Xue, Han; Zhao, Jun-Wei; Pan, Rui; Yang, Bai-Feng; Yang, Guo-Yu; Liu, Hong-Sheng

    2016-08-22

    Under hydrothermal conditions, replacement of the water molecules in the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster of mixed-valent Mn6 sandwiched silicotungstate [(B-α-SiW9 O34 )2 Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](12-) (1 a) with organic N ligands led to the isolation of five organic-inorganic hybrid, Mn6 -substituted polyoxometalates (POMs) 2-6. They were all structurally characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, diffuse-reflectance spectroscopy, and powder and single-crystal X-ray diffraction. Compounds 2-6 represent the first series of mixed-valent {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } sandwiched POMs covalently functionalized by organic ligands. The preparation of 1-6 not only indicates that the double-cubane {Mn(III) 4 Mn(II) 2 O4 (H2 O)4-n (L)n } clusters are very stable fragments in both conventional aqueous solution and hydrothermal systems and that organic functionalization of the [Mn(III) 4 Mn(II) 2 O4 (H2 O)4 ](8+) cluster by substitution reactions is feasible, but also demonstrates that hydrothermal environments can promote and facilitate the occurrence of this substitution reaction. This work confirms that hydrothermal synthesis is effective for making novel mixed-valent POMs substituted with transition-metal (TM) clusters by combining lacunary Keggin precursors with TM cations and tunable organic ligands. Furthermore, magnetic measurements reveal that 3 and 6 exhibit single-molecule magnet behavior.

  17. MAGNET

    CERN Multimedia

    by B. Curé

    2011-01-01

    The magnet operation was very satisfactory till the technical stop at the end of the year 2010. The field was ramped down on 5th December 2010, following the successful regeneration test of the turbine filters at full field on 3rd December 2010. This will limit in the future the quantity of magnet cycles, as it is no longer necessary to ramp down the magnet for this type of intervention. This is made possible by the use of the spare liquid Helium volume to cool the magnet while turbines 1 and 2 are stopped, leaving only the third turbine in operation. This obviously requires full availability of the operators to supervise the operation, as it is not automated. The cryogenics was stopped on 6th December 2010 and the magnet was left without cooling until 18th January 2011, when the cryoplant operation resumed. The magnet temperature reached 93 K. The maintenance of the vacuum pumping was done immediately after the magnet stop, when the magnet was still at very low temperature. Only the vacuum pumping of the ma...

  18. Nanocomposite Nd10Fe84-xB6Inx (x=0, 1) Permanent Magnet and Its Heat-treatment Behavior

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Nanocomposite magnet of Nd10Fe84-xB6lnx (x=0,1) has been fabricated and magnetic properties have been in vestigated. Addition of indium damages the magnetic behavior, but can change its heat-treatment effect. Annealing does not improve the properties very much to the In-free magnet, but changes the intrinsic coercivity of Nd10Fe83B6ln obviously.

  19. Mirroring the dynamic magnetic behavior of magnetostrictive Co/(Ag,Cu,Ta) multilayers grown onto rigid and flexible substrates

    Energy Technology Data Exchange (ETDEWEB)

    Agra, K.; Gomes, R.R. [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Della Pace, R.D. [Departamento de Física, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Departamento de Física, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Dorneles, L.S. [Departamento de Física, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Bohn, F. [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil); Corrêa, M.A., E-mail: marciocorrea@dfte.ufrn.br [Departamento de Física, Universidade Federal do Rio Grande do Norte, 59078-900 Natal, RN (Brazil)

    2015-11-01

    We investigate the magnetoimpedance effect in a wide frequency range in magnetostrictive Co/(Ag,Cu,Ta) multilayers grown onto rigid and flexible substrates. We observe a direct correlation between structural and quasi-static magnetic properties and the magnetoimpedance effect, since they are directly dependent on the nature of the spacer material. Moreover, we verify that all these properties are insensitive to the kind of employed substrate. We compare the magnetoimpedance results measured for multilayers in rigid and flexible substrates and discuss them in terms of different mechanisms that govern the impedances changes, magnetic anisotropy, structural character, and of numerical calculation results found in the literature. The fact that magnetostrictive multilayers can be reproduced in distinct kinds of substrates corresponds to an important advance for their applicability. The results place multilayers grown onto flexible substrates as attractive candidates for application as probe element in the development of MI-based sensor devices. - Highlights: • Correlation between structural and magnetic properties. • Dynamic magnetic behavior of multilayers trough MI effect. • Mirroring the dynamic magnetic behavior in flexible and rigid substrates. • Flexible substrate applications for magnetostrictive alloys.

  20. A magnetic-dependent protein corona of tailor-made superparamagnetic iron oxides alters their biological behaviors.

    Science.gov (United States)

    Liu, Ziyao; Zhan, Xiaohui; Yang, Minggang; Yang, Qi; Xu, Xianghui; Lan, Fang; Wu, Yao; Gu, Zhongwei

    2016-04-14

    In recent years, it is becoming increasingly evident that once nanoparticles come into contact with biological fluids, a protein corona surely forms and critically affects the biological behaviors of nanoparticles. Herein, we investigate whether the formation of protein corona on the surface of superparamagnetic iron oxides (SPIOs) is influenced by static magnetic field. Under static magnetic field, there is no obvious variation in the total amount of protein adsorption, but the proportion of adsorbed proteins significantly changes. Noticeably, certain proteins including apolipoproteins, complement system proteins and acute phase proteins, increase in the protein corona of SPIOs in the magnetic field. More importantly, the magnetic-dependent protein corona of SPIOs enhances the cellular uptake of SPIOs into the normal cell line (3T3 cells) and tumor cell line (HepG2 cells), due to increased adsorption of apolipoprotein. In addition, SPIOs with the magnetic-dependent protein corona cause high cytotoxicity to 3T3 cells and HepG2 cells. This work discloses that superparamagnetism as a key feature of SPIOs affects the composition of protein corona to a large extent, which further alters the biological behaviors of SPIOs.

  1. Influence of ambient temperature and AC magnetic field on damping behavior of Fe-13Cr-2.5Mo alloy

    Science.gov (United States)

    Xu, Yong-gang; Li, Ning; Shen, Bao-luo; Hua, Hong-xing

    2007-07-01

    The damping behaviors of Fe-13Cr-2.5Mo alloy at ambient temperatures and the AC magnetic field are tested with the improved reversal torsion machine. The precipitations distributing in the annealed alloy are also observed with SEM. The results show that because the defections decrease during the annealing treatment, causing a higher damping capacity of this alloy. This damping drops linearly to 63% when the ambient temperature changes from 23 °C to 500 °C, resulting from the gradual decrease of ferromagnetism. On the other hand, the AC magnetic field causes the damping capacity to drop sharply, and finally it reaches a much lower level.

  2. Behavior of mixed ZnO and SiO2 nano-particles in magnetic field assisted fluidization

    Institute of Scientific and Technical Information of China (English)

    Ping Zeng; Tao Zhou; Guanqun Chen; Qingshan Zhu

    2007-01-01

    The fluidization behavior of ZnO nano-particles in magnetic fluidized bed (MFB) by adding coarse magnetic particles was investigated, followed by the co-fluidization of mixtures of ZnO and SiO2 nano-particles. For such co-fluidization, bed expansion was found to change smoothly with gas velocity through a range of stable operation. By measuring the bed expansion ratio and pressure drop, a stability diagram for the mixture in MFB was obtained. Within this stable operation range, with increasing gas velocity the pressure drop hardly changes as the bed expands, up to an expansion ratio of more than 4.

  3. Field-improvised war surgery in Kosovo: use of kitchen utensils as surgical instruments.

    Science.gov (United States)

    Hoxha, Besim; Singh, Karan P; Muzina, Rubina; Lu, Yan; Flaherty, Devin

    2008-06-01

    After years of conflict between Serbia and neighboring Kosovo, a full-blown war started in March 1999 when the Serbian and Yugoslav armies began a statewide military crackdown against ethnic Albanians and the Kosovo Liberation Army. Most ethnic Albanians were displaced to Macedonia or Albania. Some, however, found refuge in the Molopolce mountain region of Kosovo among military personnel, thus necessitating the creation of a field medical facility. Patient treatment at the field-improvised Nerodime Military Hospital, and the management of work took place under very difficult conditions including a chronic lack of appropriate medical equipment. Improvised lifesaving surgeries were performed with kitchen utensils serving as retractors at the field hospital. This article compares the treatment of patients between the two hospitals, and is the first article to date describing the war experience in general at the field hospitals in Kosovo.

  4. Getting it Right: The Endurance of Improvised Explosive Device Education in the US Army

    Science.gov (United States)

    2017-05-25

    establishments, or via online retailers , without requiring special training or licensing beyond the capability of the average individual. The first section...Smith, Improvised Explosive Devices in Iraq, 2003-09: A Case of Operational Surprise and Institutional Response, Letort Paper (Carlisle, PA: Strategic...accessed April 20, 2017, http://www.hoover.org/ research /vietnam-iraq-afghanistan-different-or-same. 30 defeat Victim Operated IEDs (VOIEDs

  5. Modulating the magnetic behavior of Fe(II)-MOF-74 by the high electron affinity of the guest molecule.

    Science.gov (United States)

    Han, Sungmin; Kim, Heejin; Kim, Jaehoon; Jung, Yousung

    2015-07-14

    As a new class of magnetic materials, metal-organic framework (MOF) has received a significant attention due to their functionality and porosity that can provide diverse magnetic phenomena by utilizing host-guest chemistry. For Fe-MOF-74, we here find using density functional calculations that the O2 and C2H4 adsorptions result in the ferromagnetic (FM) and antiferromagnetic (AFM) orderings along the 1D chain of an hexagonal MOF framework, respectively, while their adsorption energies, pi-complexation, and geometrical changes are all similar upon binding. We reveal that this different magnetism behavior is attributed to the different electronic effects, where the adsorbed O2 greatly withdraws a minor spin electron from the Fe centers. The latter significant back donation opens a new channel for superexchange interactions that can enhance the FM coupling between Fe centers, where the strength of calculated intrachain FM coupling constrant (Jin) in O2 adsorbed Fe-MOF-74 is more than 10 times enhanced compared to bare Fe-MOF-74. This prediction suggests a possibility for the conceptual usage of Fe-MOF-74 as a gas sensor based on its magnetic changes caused by the adsorbed gases. Furthermore, the suggested mechanism might be used to control the magnetic properties of MOFs using the guest molecules, although concrete strategies to enhance such magnetic interactions to be used in practical applications would require further significant investigation.

  6. Structural Anomalies and Multiferroic Behavior in Magnetically Frustrated TbMn2O5

    NARCIS (Netherlands)

    Chapon, L.C.; Blake, G.R.; Gutmann, M.J.; Park, S.; Hur, N.; Radaelli, P.G.; Cheong, S-W.

    2004-01-01

    We have studied the magnetostructural phase diagram of multiferroic TbMn2O5 as a function of temperature and magnetic field by neutron diffraction. Dielectric and magnetic anomalies are found to be associated with steps in the magnetic propagation vector, including a rare example of a commensurate-i

  7. Structural Anomalies and Multiferroic Behavior in Magnetically Frustrated TbMn2O5

    NARCIS (Netherlands)

    Chapon, L.C.; Blake, G.R.; Gutmann, M.J.; Park, S.; Hur, N.; Radaelli, P.G.; Cheong, S-W.

    2004-01-01

    We have studied the magnetostructural phase diagram of multiferroic TbMn2O5 as a function of temperature and magnetic field by neutron diffraction. Dielectric and magnetic anomalies are found to be associated with steps in the magnetic propagation vector, including a rare example of a commensurate-i

  8. An improvisation on the Middle-Eastern mijwiz; auditory roughness profiles and tension/release patterns

    Science.gov (United States)

    Vassilakis, Pantelis N.

    2005-04-01

    Within western musical tradition, auditory roughness constitutes one of the principle perceptual correlates of dissonance. A previous study [P. N. Vassilakis, Selected Reports in Ethnomusicology, Vol. 12 (in press)] addressed the musical significance of auditory roughness within western as well as three non-western musical traditions. It introduced a new roughness estimation model that predicts successfully roughness ratings of synthesized complex diatonic dyads. For the present study, an application was created that uses the aforementioned model to estimate the roughness of natural signals with arbitrary spectra, as well as roughness profiles of short musical pieces. The application was used to examine if and how the pattern of tension and release within a stylized improvisation on the Middle Eastern mijwiz (double clarinet) relates to roughness changes. Tension/release patterns were indicated by the Lebanese improviser and expert mijwiz player (Dr. A. J. Racy) and were also obtained by both musicians and non-musicians (American-raised) in a perceptual experiment. The results suggest that auditory roughness is a good predictor of the tension/release pattern indicated by the improviser. The patterns obtained by the subjects, although not very consistent, appear to be different overall, suggesting that musical tension and release may be culture-specific concepts.

  9. Core Themes in Music Therapy Clinical Improvisation: An Arts-Informed Qualitative Research Synthesis.

    Science.gov (United States)

    Meadows, Anthony; Wimpenny, Katherine

    2017-07-01

    Although clinical improvisation continues to be an important focus of music therapy research and practice, less attention has been given to integrating qualitative research in this area. As a result, this knowledge base tends to be contained within specific areas of practice rather than integrated across practices and approaches. This qualitative research synthesis profiles, integrates, and re-presents qualitative research focused on the ways music therapists and clients engage in, and make meaning from, clinical improvisation. Further, as a conduit for broadening dialogues, opening up this landscape fully, and sharing our response to the analysis and interpretation process, we present an arts-informed re-presentation of this synthesis. Following an eight-step methodological sequence, 13 qualitative studies were synthesized. This included reciprocal and refutational processes associated with synthesizing the primary studies, and additional steps associated with an arts-informed representation. Three themes, professional artistry, performing self, and meaning-making, are presented. Each theme is explored and exemplified through the selected articles, and discussed within a larger theoretical framework. An artistic re-presentation of the data is also presented. Music therapists use complex frameworks through which to engage clients in, and make meaning from, improvisational experiences. Artistic representation of the findings offers an added dimension to the synthesis process, challenging our understanding of representation, and thereby advancing synthesis methodology.

  10. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet was energised at the beginning of March 2012 at a low current to check all the MSS safety chains. Then the magnet was ramped up to 3.8 T on 6 March 2012. Unfortunately two days later an unintentional switch OFF of the power converter caused a slow dump. This was due to a misunderstanding of the CCC (CERN Control Centre) concerning the procedure to apply for the CMS converter control according to the beam-mode status at that time. Following this event, the third one since 2009, a discussion was initiated to define possible improvement, not only on software and procedures in the CCC, but also to evaluate the possibility to upgrade the CMS hardware to prevent such discharge from occurring because of incorrect procedure implementations. The magnet operation itself was smooth, and no power cuts took place. As a result, the number of magnetic cycles was reduced to the minimum, with only two full magnetic cycles from 0 T to 3.8 T. Nevertheless the magnet suffered four stops of the cryogeni...

  11. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    Operation of the magnet has gone quite smoothly during the first half of this year. The magnet has been at 4.5K for the full period since January. There was an unplanned short stop due to the CERN-wide power outage on May 28th, which caused a slow dump of the magnet. Since this occurred just before a planned technical stop of the LHC, during which access in the experimental cavern was authorized, it was decided to leave the magnet OFF until 2nd June, when magnet was ramped up again to 3.8T. The magnet system experienced a fault also resulting in a slow dump on April 14th. This was triggered by a thermostat on a filter choke in the 20kA DC power converter. The threshold of this thermostat is 65°C. However, no variation in the water-cooling flow rate or temperature was observed. Vibration may have been the root cause of the fault. All the thermostats have been checked, together with the cables, connectors and the read out card. The tightening of the inductance fixations has also been checked. More tem...

  12. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      Following the unexpected magnet stops last August due to sequences of unfortunate events on the services and cryogenics [see CMS internal report], a few more events and initiatives again disrupted the magnet operation. All the magnet parameters stayed at their nominal values during this period without any fault or alarm on the magnet control and safety systems. The magnet was stopped for the September technical stop to allow interventions in the experimental cavern on the detector services. On 1 October, to prepare the transfer of the liquid nitrogen tank on its new location, several control cables had to be removed. One cable was cut mistakenly, causing a digital input card to switch off, resulting in a cold-box (CB) stop. This tank is used for the pre-cooling of the magnet from room temperature down to 80 K, and for this reason it is controlled through the cryogenics control system. Since the connection of the CB was only allowed for a field below 2 T to avoid the risk of triggering a fast d...

  13. Effects of High Magnetic Field on Recrystallization Behavior in Fe-Si Alloys

    Institute of Scientific and Technical Information of China (English)

    Ya Xu; H.Ohtsuka; S.Umezawa; K.Anak; S.Miyazaki; H.Wada

    2000-01-01

    Effects of high magnetic field on recrystallization, coarsening after primary recrystallization and texture evolution were studied in non-oriented and oriented 3% silicon steels. The highest applied magnetic field strength was 10 Tesla. It was found that primary recrystallization process and coarsening after primary recrystallization are both retarded by the application of magnetic field during annealing. A difference between primary recrystallization textures annealed with or without a magnetic field was found in both non-oriented and oriented 3% silicon specimens. It was found that the amount of texture component { 111 } increases by the application of magnetic field during annealing.

  14. Perpendicular Magnetic Anisotropy and Spin Glass-like Behavior in Molecular Beam Epitaxy Grown Chromium Telluride Thin Films.

    Science.gov (United States)

    Roy, Anupam; Guchhait, Samaresh; Dey, Rik; Pramanik, Tanmoy; Hsieh, Cheng-Chih; Rai, Amritesh; Banerjee, Sanjay K

    2015-04-28

    Reflection high-energy electron diffraction (RHEED), scanning tunneling microscopy (STM), vibrating sample magnetometry, and other physical property measurements are used to investigate the structure, morphology, magnetic, and magnetotransport properties of (001)-oriented Cr2Te3 thin films grown on Al2O3(0001) and Si(111)-(7×7) surfaces by molecular beam epitaxy. Streaky RHEED patterns indicate flat smooth film growth on both substrates. STM studies show the hexagonal arrangements of surface atoms. Determination of the lattice parameter from the atomically resolved STM image is consistent with the bulk crystal structures. Magnetic measurements show the film is ferromagnetic, having a Curie temperature of about 180 K, and a spin glass-like behavior was observed below 35 K. Magnetotransport measurements show the metallic nature of the film with a perpendicular magnetic anisotropy along the c-axis.

  15. Monte Carlo simulations on magnetic behavior of a spin-chain system in triangular lattice doped with antiferromagnetic bonds

    Institute of Scientific and Technical Information of China (English)

    YAO Xiao-yan; LI Peng-lei; DONG Shuai; LIU Jun-ming

    2007-01-01

    A three-dimensional Ising-like model doped with anti-ferromagnetic (AFM) bonds is proposed to investigate the magnetic properties of a doped triangular spin-chain system by using a Monte-Carlo simulation. The simulated results indicate that a steplike magnetization behavior is very sensitive to the concentration of AFM bonds. A low concentration of AFM bonds can suppress the stepwise behavior considerably, in accordance with doping experiments on Ca3Co206. The analysis of spin snapshots demonstrates that the AFM bond doping not only breaks the ferromagnetic ordered linear spin chains along the hexagonal c-axis but also has a great influence upon the spin configuration in the ab-plane.

  16. Critical Behavior of the Gaussian Model with Periodic Interactions on Diamond-Type Hierarchical Lattices in External Magnetic Fields

    Institute of Scientific and Technical Information of China (English)

    LIN ZhenQuan; KONG XiangMu; JIN JinShuang; YANG ZhanRu

    2001-01-01

    The Gaussian spin model with periodic interactions on the diamond-type hierarchical lattices is constructed by generalizing that with uniform interactions on translationally invariant lattices according to a class of substitution sequences. The Gaussian distribution constants and imposed external magnetic fields are also periodic depending on the periodic characteristic of the interaction bonds. The critical behaviors of this generalized Gaussian model in external magnetic fields are studied by the exact renormalization-group approach and spin rescaling method. The critical points and all the critical exponents are obtained. The critical behaviors are found to be determined by the Gaussian distribution constants and the fractal dimensions of the lattices. When all the Gaussian distribution constants are the same, the dependence of the critical exponents on the dimensions of the lattices is the same as that of the Gaussian model with uniform interactions on translationally invariant lattices.

  17. Differential parietal and temporal contributions to music perception in improvising and score-dependent musicians, an fMRI study.

    Science.gov (United States)

    Harris, Robert; de Jong, Bauke M

    2015-10-22

    Using fMRI, cerebral activations were studied in 24 classically-trained keyboard performers and 12 musically unskilled control subjects. Two groups of musicians were recruited: improvising (n=12) and score-dependent (non-improvising) musicians (n=12). While listening to both familiar and unfamiliar music, subjects either (covertly) appraised the presented music performance or imagined they were playing the music themselves. We hypothesized that improvising musicians would exhibit enhanced efficiency of audiomotor transformation reflected by stronger ventral premotor activation. Statistical Parametric Mapping revealed that, while virtually 'playing along׳ with the music, improvising musicians exhibited activation of a right-hemisphere distribution of cerebral areas including posterior-superior parietal and dorsal premotor cortex. Involvement of these right-hemisphere dorsal stream areas suggests that improvising musicians recruited an amodal spatial processing system subserving pitch-to-space transformations to facilitate their virtual motor performance. Score-dependent musicians recruited a primarily left-hemisphere pattern of motor areas together with the posterior part of the right superior temporal sulcus, suggesting a relationship between aural discrimination and symbolic representation. Activations in bilateral auditory cortex were significantly larger for improvising musicians than for score-dependent musicians, suggesting enhanced top-down effects on aural perception. Our results suggest that learning to play a music instrument primarily from notation predisposes musicians toward aural identification and discrimination, while learning by improvisation involves audio-spatial-motor transformations, not only during performance, but also perception. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Magnetic field and in situ stress dependence of elastic behavior in EuTiO3 from resonant ultrasound spectroscopy

    Science.gov (United States)

    Schiemer, Jason; Spalek, Leszek J.; Saxena, Siddharth S.; Panagopoulos, Christos; Katsufuji, Takuro; Bussmann-Holder, Annette; Köhler, Jürgen; Carpenter, Michael A.

    2016-02-01

    Magnetoelectric coupling phenomena in EuTiO3 are of considerable fundamental interest and are also understood to be key to reported multiferroic behavior in strained films, which exhibit distinctly different properties to the bulk. Here, the magnetoelastic coupling of EuTiO3 is investigated by resonant ultrasound spectroscopy with in situ applied magnetic field and stress as a function of temperature ranging from temperatures above the structural transition temperature T s to below the antiferromagnetic ordering temperature T n. One single crystal and two polycrystalline samples are investigated and compared to each other. Both paramagnetic and diamagnetic transducer carriers are used, allowing an examination of the effect of both stress and magnetic field on the behavior of the sample. The properties are reported in constant field/variable temperature and in constant temperature/variable field mode where substantial differences between both data sets are observed. In addition, elastic and magnetic poling at high fields and stresses at low temperature has been performed in order to trace the history dependence of the elastic constants. Four different temperature regions are identified, characterized by unusual elastic responses. The low-temperature phase diagram has been explored and found to exhibit rich complexity. The data evidence a considerable relaxation of elastic constants at high temperatures, but with little effect from magnetic field alone above 20 K, in addition to the known low-temperature coupling.

  19. MAGNET

    CERN Multimedia

    B. Curé

    2012-01-01

      The magnet and its sub-systems were stopped at the beginning of the winter shutdown on 8th December 2011. The magnet was left without cooling during the cryogenics maintenance until 17th January 2012, when the cryoplant operation resumed. The magnet temperature reached 93 K. The vacuum pumping was maintained during this period. During this shutdown, the yearly maintenance was performed on the cryogenics, the vacuum pumps, the magnet control and safety systems, and the power converter and discharge lines. Several preventive actions led to the replacement of the electrovalve command coils, and the 20A DC power supplies of the magnet control system. The filters were cleaned on the demineralised water circuits. The oil of the diffusion pumps was changed. On the cryogenics, warm nitrogen at 343 K was circulated in the cold box to regenerate the filters and the heat exchangers. The coalescing filters have been replaced at the inlet of both the turbines and the lubricant trapping unit. The active cha...

  20. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet was successfully operated at the end of the year 2009 despite some technical problems on the cryogenics. The magnet was ramped up to 3.8 T at the end of November until December 16th when the shutdown started. The magnet operation met a few unexpected stops. The field was reduced to 3.5 T for about 5 hours on December 3rd due to a faulty pressure sensor on the helium compressor. The following day the CERN CCC stopped unintentionally the power converters of the LHC and the experiments, triggering a ramp down that was stopped at 2.7 T. The magnet was back at 3.8 T about 6 hours after CCC sent the CERN-wide command. Three days later, a slow dump was triggered due to a stop of the pump feeding the power converter water-cooling circuit, during an intervention on the water-cooling plant done after several disturbances on the electrical distribution network. The magnet was back at 3.8 T in the evening the same day. On December 10th a break occurred in one turbine of the cold box producing the liquid ...

  1. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

      The magnet was operated without any problem until the end of the LHC run in February 2013, apart from a CERN-wide power glitch on 10 January 2013 that affected the CMS refrigerator, causing a ramp down to 2 T in order to reconnect the coldbox. Another CERN-wide power glitch on 15 January 2013 didn’t affect the magnet subsystems, the cryoplant or the power converter. At the end of the magnet run, the reconnection of the coldbox at 2.5 T was tested. The process will be updated, in particular the parameters of some PID valve controllers. The helium flow of the current leads was reduced but only for a few seconds. The exercise will be repeated with the revised parameters to validate the automatic reconnection process of the coldbox. During LS1, the water-cooling services will be reduced and many interventions are planned on the electrical services. Therefore, the magnet cryogenics and subsystems will be stopped for several months, and the magnet cannot be kept cold. In order to avoid unc...

  2. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The CMS magnet has been running steadily and smoothly since the summer, with no detected flaw. The magnet instrumentation is entirely operational and all the parameters are at their nominal values. Three power cuts on the electrical network affected the magnet run in the past five months, with no impact on the data-taking as the accelerator was also affected at the same time. On 22nd June, a thunderstorm caused a power glitch on the service electrical network. The primary water cooling at Point 5 was stopped. Despite a quick restart of the water cooling, the inlet temperature of the demineralised water on the busbar cooling circuit increased by 5 °C, up to 23.3 °C. It was kept below the threshold of 27 °C by switching off other cooling circuits to avoid the trigger of a slow dump of the magnet. The cold box of the cryogenics also stopped. Part of the spare liquid helium volume was used to maintain the cooling of the magnet at 4.5 K. The operators of the cryogenics quickly restarted ...

  3. Interrogating the origin and behavior of magnetic resonance diffusion tensor scalar parameters in the myocardium

    Science.gov (United States)

    Abdullah, Osama Mahmoud

    Myocardial microstructure plays an important role in sustaining the orchestrated beating motion of the heart. Several microstructural components, including myocytes and auxiliary cells, extracellular space, and blood vessels provide the infrastructure for normal heart function, including excitation propagation, myocyte contraction, delivery of oxygen and nutrients, and removing byproduct wastes. Cardiac diseases cause deleterious changes to some or all of these microstructural components in the detrimental process of cardiac remodeling. Since heart failure is among the leading causes of death in the world, new and novel tools to noninvasively characterize heart microstructure are needed for monitoring and staging of cardiac disease. In this regards, diffusion magnetic resonance imaging (MRI) provides a promising framework to probe and quantify tissue microstructure without the need for exogenous contrast agent. As diffusion in 3-dimensional space is characterized by the diffusion tensor, MR diffusion tensor imaging (DTI) is being used to noninvasively measure anisotropic diffusion, and thus the magnitude and spatial orientation of microstructural organization of tissues, including the heart. However, even though in vivo cardiac DTI has become more clinically available, to date the origin and behavior of different microstructural components on the measured DTI signal remain to be explicitly specified. The presented studies in this work demonstrate that DTI can be used as a noninvasive and contrast-free imaging modality to characterize myocyte size and density, extracellular collagen content, and the directional magnitude of blood flow. The identified applications are expected to provide metrics to enable physicians to detect, quantify, and stage different microstructural components during progression of cardiac disease.

  4. MAGNETS

    Science.gov (United States)

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  5. Anomalous magnetic behavior for Mn-site doped La{sub 0.7}Ca{sub 0.3}MnO{sub 3}: internal magnetic interactions and extrinsic inhomogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hong-guang, E-mail: hgzhang_njupt@hotmail.com [College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Li, Yong-tao [College of Science, Nanjing University of Posts and Telecommunications, Nanjing 210046 (China); Xie, Liang [Department of Physical and Chemical Sciences, North China University of Technology, Beijing 100144 (China); Shi, Jiang-jian; Dong, Xue-guang; Ge, Xiao-peng; Liu, Hao [Physics Department, Southeast University, Nanjing 211189 (China); Li, Qi, E-mail: qli@seu.edu.cn [Physics Department, Southeast University, Nanjing 211189 (China)

    2015-11-01

    Magnetic properties of Mn-site doped La{sub 0.7}Ca{sub 0.3}Mn{sub 0.94}TM{sub 0.06}O{sub 3+Δ} (TM=Cu, Zn) were experimentally and theoretically studied. The low-temperature magnetization and magnetic phase transition temperature T{sub C} of the samples combining with simulations of 2D doped Ising model suggest that Cu{sup 2+} ions have an antiferromagnetic interaction with their nearest neighboring Mn ions. Interestingly, an anomalous magnetic behavior, a “step-like” magnetic phase transition, is observed. The existence and magnitude of this step vary with different doping ions and oxygen ratio, which is experimentally suggested to be relevant to the interaction between magnetic ions and oxygen content. A superposition between two independent magnetic systems with different values of an exchange integral J well explains the anomalous magnetic phase transition, which suggests that this step-like behavior results from extrinsic inhomogeneity and negligible coupling between grains in polycrystalline. - Highlights: • A “step-like” magnetic phase transition is observed in La{sub 0.7}Ca{sub 0.3}Mn{sub 0.94}TM{sub 0.06}O{sub 3}. • An anomalous magnetic property is experimentally and theoretically studied. • The evolution of T{sub C} and low T magnetization opposite to conventional behavior. • An antiferromagnetic interaction between Cu{sup 2+} and Mn ion is investigated by Ising model. • A linear superposition between magnetic behaviors explain the phase transition.

  6. Surface supramolecular organization of a terbium(III) double-decker complex on graphite and its single molecule magnet behavior.

    Science.gov (United States)

    Gonidec, Mathieu; Biagi, Roberto; Corradini, Valdis; Moro, Fabrizio; De Renzi, Valentina; del Pennino, Umberto; Summa, Domenico; Muccioli, Luca; Zannoni, Claudio; Amabilino, David B; Veciana, Jaume

    2011-05-01

    The two-dimensional self-assembly of a terbium(III) double-decker phthalocyanine on highly oriented pyrolitic graphite (HOPG) was studied by atomic force microscopy (AFM), and it was shown that it forms highly regular rectangular two-dimensional nanocrystals on the surface, that are aligned with the graphite symmetry axes, in which the molecules are organized in a rectangular lattice as shown by scanning tunneling microscopy. Molecular dynamics simulations were run in order to model the behavior of a collection of the double-decker complexes on HOPG. The results were in excellent agreement with the experiment, showing that-after diffusion on the graphite surface-the molecules self-assemble into nanoscopic islands which align preferentially along the three main graphite axes. These low dimension assemblies of independent magnetic centers are only one molecule thick (as shown by AFM) and are therefore very interesting nanoscopic magnetic objects, in which all of the molecules are in interaction with the graphite substrate and might therefore be affected by it. The magnetic properties of these self-assembled bar-shaped islands on HOPG were studied by X-ray magnetic circular dichroism, confirming that the compounds maintain their properties as single-molecule magnets when they are in close interaction with the graphite surface.

  7. Thermal annealing effects on the magnetic behavior of Ce{sub 2}NiSi{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, D.P., E-mail: rojasd@unican.e [Departamento CITIMAC, Universidad de Cantabria, Av de los Castros S/N, Santander 39005 (Spain); Rodriguez Fernandez, J.; Espeso, J.I.; Gomez Sal, J.C. [Departamento CITIMAC, Universidad de Cantabria, Av de los Castros S/N, Santander 39005 (Spain); Silva, L.M. da [Centro de Ciencias Sociais, Saude e Tecnologia, UFMA, R. Urbano Santos, s/n, 65900-000, Imperatriz, MA (Brazil); Gandra, F.G. [Instituto de Fisica ' Gleb Wataghin' , UNICAMP, 13083-970, Campinas, SP (Brazil); Santos, A.O. dos [Centro de Ciencias Sociais, Saude e Tecnologia, UFMA, R. Urbano Santos, s/n, 65900-000, Imperatriz, MA (Brazil); Medina, A.N. [Departamento de Fisica, Universidade Estadual de Maringa, 87020-900, Maringa, PR (Brazil)

    2010-10-15

    We have investigated the crystallographic, magnetic and thermodynamic properties of the as-cast and annealed Ce{sub 2}NiSi{sub 3} alloys, crystallizing in the AlB{sub 2}-type hexagonal structure. The DC-magnetic susceptibility data show that the as-cast sample exhibits an antiferromagnetic (AFM) ordering below T{sub N}= 3.8 K, whereas the annealed sample shows, at 4.2 K, a magnetic transition of AFM nature and, around 2.5 K, an additional anomaly. The specific heat shows a peak with c{sub max}=7.4J/molK at 3.8 K for the as cast sample, which shifts to lower temperatures when the magnetic field increases, consistent with the antiferromagnetic nature of the transition. On the other hand, in the annealed alloy, the maximum of the specific heat peak reaches 9.3J/molK at 4.2 K, and no additional anomalies were observed. The different magnetic behavior between the as-cast and annealed samples is attributed to thermal effects on the structural disorder of nickel and silicon atoms, as already observed in other isotypic R{sub 2}TSi{sub 3} alloys, where R=U or Ce, and T= transition metal.

  8. Electron microscopy observations of surface morphologies and particle arrangement behaviors of magnetic fluids

    Institute of Scientific and Technical Information of China (English)

    沈辉; 徐雪青; 王伟

    2003-01-01

    The surface morphology of quasi-periodic stripe-shaped patterns of magnetite fluids was observed in applied perpendicular magnetic fields by means of scanning electron microscopy. The nanoparticles of the magnetite fluids are arranged in oriental quasilinear chains in applied perpendicular magnetic fields as observed using transmission electron microscopy. This arrangement results from particle-particle interactions and particle-carrier liquids interactions, which are eventually controlled by the magnetic fields distribution.

  9. Effect of Co content on structure and magnetic behaviors of high induction Fe-based amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Rajat K., E-mail: rajat@nmlindia.org; Panda, Ashis K.; Mitra, Amitava

    2016-11-15

    The replacement of Fe with Co is investigated in the (Fe{sub 1−x}Co{sub x}){sub 79}Si{sub 8.5}B{sub 8.5}Nb{sub 3}Cu{sub 1} (x=0, 0.05, 0.2, 0.35, 0.5) amorphous alloys. The alloys are synthesized in the forms of ribbons by single roller melt spinning technique, and the structural and magnetic properties of annealed ribbons are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM), B–H curve tracer, respectively. All as-cast alloys are structurally amorphous, however, their magnetic properties are varying with Co addition. The Co addition within 5–20 at% results in moderate thermal stability, saturation induction, Curie temperature and lowest coercivity, while 35 at% Co causes highest saturation induction, coercivity, Curie temperature and lowest thermal stability. On devitrification, the magnetic properties change with the generation of α-FeCo nanocrystallites and (FeCo){sub 23}B{sub 6}, Fe{sub 2}B phases during primary and secondary crystallization stages, respectively. A small amount Co is advantageous for maintaining finer nanocrystallites in amorphous matrix even after annealing at 600 °C, leading to high saturation magnetization (>1.5 T) and low coercivity (~35 A/m). The improved magnetic properties at elevated temperatures indicate these alloys have a potential for high frequency transformer core applications. - Highlights: • The structural and magnetic behaviors of Fe based amorphous alloys have been investigated with the effect of Co content. • The Co has no adverse effect on amorphization of alloys. • A small amount Co causes the superior improvement of magnetic properties at elevated temperatures. • Therefore, it is important not only for academic research but also for industrial applied research.

  10. Enhanced magnetic and dielectric behavior in Co doped BiFeO{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Chakrabarti, Kaushik; Sarkar, Babusona; Ashok, Vishal Dev [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India); Chaudhuri, Sheli Sinha [Department of Electronics and Telecommunication Engineering, Jadavpur University, Kolkata-700032 (India); De, S.K., E-mail: msskd@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032 (India)

    2015-05-01

    Magnetic and dielectric properties of Co doped BiFeO{sub 3} (BFO) nanoparticles (13 nm) have been investigated. The dopant Co{sup 2+} converts spherical morphology to cubic nanostructures. The significant changes in temperature dependence of magnetization may be due to magnetic disorder phase induced by divalent Co. The substitution of Fe by Co disrupts cycloidal spin structure of BFO and improves the ferromagnetic property. Enhancement of the saturation magnetization and coercivity by about 10 times in doped BFO are due to changes in morphology. High dielectric constant of about 670 and low loss at room temperature show Co doped BFO as promising material for multifunctional devices.

  11. Distinguishing Magnetic Behavior on the Slater-Pauling Curve applied to nanoscale thin films.

    Science.gov (United States)

    Podolak, K. R.; Birke, M. G.; Janke-Gilman, N.; Willis, R. F.

    2006-03-01

    The Slater-Pauling curve is a plot of the stoichiometric mean saturation magnetization per atom as a function of the electron filling of the d-bands in the transition metals and their alloys. When the elemental magnetic moments are aligned, the volcano-shape curve plots the variation of the mean magnetic moment. It has been predicted that a narrowing of the d-bands in nanostructured magnetic materials will influence both the magnitude of the magnetic moments as well as the overall magnetic alignment through increased spin-orbit coupling [1]. In this paper, we report dichroism in the core-level x-ray photoemission spectra of the elements which reveals and distinguishes the changing magnitudes of the magnetic moments and the changing alignment of these moments with changing composition. The 3p core-level spectral densities of multiplet spin-ordered states show a width W proportional to the local Zeeman splitting of levels, and a magnetic dichroism amplitude A sensitive to the non-local magnetic order (anisotropy). In nanoscale epitaxial layers, small deviations from the bulk Slater-Pauling curve are observed due to enhanced moments due to d-band narrowing [2]. It is predicted that a plot of the spectral parameters W, A will show a different dependence of temperature approaching Tc, the critical ordering temperature. [1] S. Handschuh & S. Blügel, Solid State Communications. 105, 633 (1998). [2] R.F. Willis & N. Janke-Gilman, Europhysics Letters. 69, 411 (2005).

  12. Child-Computer Interaction at the Beginner Stage of Music Learning: Effects of Reflexive Interaction on Children's Musical Improvisation.

    Science.gov (United States)

    Addessi, Anna Rita; Anelli, Filomena; Benghi, Diber; Friberg, Anders

    2017-01-01

    In this article children's musical improvisation is investigated through the "reflexive interaction" paradigm. We used a particular system, the MIROR-Impro, implemented in the framework of the MIROR project (EC-FP7), which is able to reply to the child playing a keyboard by a "reflexive" output, mirroring (with repetitions and variations) her/his inputs. The study was conducted in a public primary school, with 47 children, aged 6-7. The experimental design used the convergence procedure, based on three sample groups allowing us to verify if the reflexive interaction using the MIROR-Impro is necessary and/or sufficient to improve the children's abilities to improvise. The following conditions were used as independent variables: to play only the keyboard, the keyboard with the MIROR-Impro but with not-reflexive reply, the keyboard with the MIROR-Impro with reflexive reply. As dependent variables we estimated the children's ability to improvise in solos, and in duets. Each child carried out a training program consisting of 5 weekly individual 12 min sessions. The control group played the complete package of independent variables; Experimental Group 1 played the keyboard and the keyboard with the MIROR-Impro with not-reflexive reply; Experimental Group 2 played only the keyboard with the reflexive system. One week after, the children were asked to improvise a musical piece on the keyboard alone (Solo task), and in pairs with a friend (Duet task). Three independent judges assessed the Solo and the Duet tasks by means of a grid based on the TAI-Test for Ability to Improvise rating scale. The EG2, which trained only with the reflexive system, reached the highest average results and the difference with EG1, which did not used the reflexive system, is statistically significant when the children improvise in a duet. The results indicate that in the sample of participants the reflexive interaction alone could be sufficient to increase the improvisational skills, and necessary

  13. MAGNET

    CERN Multimedia

    B. Curé

    2011-01-01

    The magnet ran smoothly in the last few months until a fast dump occurred on 9th May 2011. Fortunately, this occurred in the afternoon of the first day of the technical stop. The fast dump was due to a valve position controller that caused the sudden closure of a valve. This valve is used to regulate the helium flow on one of the two current leads, which electrically connects the coil at 4.5 K to the busbars at room temperature. With no helium flow on the lead, the voltage drop and the temperatures across the leads increase up to the defined thresholds, triggering a fast dump through the Magnet Safety System (MSS). The automatic reaction triggered by the MSS worked properly. The helium release was limited as the pressure rise was just at the limit of the safety valve opening pressure. The average temperature of the magnet reached 72 K. It took four days to recover the temperature and refill the helium volumes. The faulty valve controller was replaced by a spare one before the magnet ramp-up resumed....

  14. Magnetically frustrated behavior in multiferroics RMn2O5 (R =Bi, Eu, and Dy): A Raman scattering study

    Science.gov (United States)

    García-Flores, A. F.; Granado, E.; Martinho, H.; Rettori, C.; Golovenchits, E. I.; Sanina, V. A.; Oseroff, S. B.; Park, S.; Cheong, S.-W.

    2007-05-01

    A temperature dependent Raman scattering study in multiferroic single crystals RMn2O5 (R =Bi, Eu, and Dy) was performed. The Raman spectra were measured in the range from 150to450cm-1 involving mostly Mn-O-Mn bending vibrations, complementing our previous work in a higher frequency range involving Mn-O stretching modes. A number of studied phonons present anomalous frequency behavior below a characteristic temperature, T*˜60-65K, such as that found for the stretching modes. The sign and magnitude of such anomalous behavior appear to be correlated with the ionic radius of R, being softening for R =Bi and hardening for R =Eu and Dy in the range between TC/TN and T*. The anomalous phonon behaviors in both bending and stretching modes are consistent with an interpretation in terms of the spin-phonon coupling in a scenario of strong magnetic correlations.

  15. Oscillatory behavior of the magnetic moments of gold-covered iron surfaces

    NARCIS (Netherlands)

    Fang, C.M.; Groot, R.A. de; Bischoff, M.M.J.; Kempen, H. van

    1998-01-01

    Local magnetic moments at iron (001) surfaces have been studied by electronic structure calculations employing the slab geometry up to 17 layers. Whereas the clean Fe(001) surface shows oscillations in the local magnetic moments, no oscillations were observed in the case of coverage by a monolayer

  16. Polar Behavior in a Magnetic Oxide Via A-Site Size Disorder

    Science.gov (United States)

    Singh, David J.; Park, Chul Hong

    2008-03-01

    Density functional calculations are used to test a new mechanism for ferroelectricity in magnetic perovskites based on A-site size disorder. Calculations of the structure and magnetic ordering of (La,Lu)MnNiO6 show that this mechanism is effective for this material, which is predicted to be both polar (ferroelectric or relaxor) and ferromagnetic, depending on the Lu concentration.

  17. The Effect of Extremely Low Frequency Alternating Magnetic Field on the Behavior of Animals in the Presence of the Geomagnetic Field

    Directory of Open Access Journals (Sweden)

    Natalia A. Belova

    2015-01-01

    Full Text Available It is known that the geomagnetic field can influence animal migration and homing. The magnetic field detection by animals is known as magnetoreception and it is possible due to two different transduction mechanisms: the first one through magnetic nanoparticles able to respond to the geomagnetic field and the second one through chemical reactions influenced by magnetic fields. Another behavior is the magnetic alignment where animals align their bodies to the geomagnetic field. It has been observed that magnetic alignment of cattle can be disrupted near electric power lines around the world. Experimentally, it is known that alternating magnetic fields can influence living beings, but the exact mechanism is unknown. The parametric resonance model proposes a mechanism to explain that effect on living beings and establishes that, in the presence of a constant magnetic field, molecules associated with biochemical reactions inside cells can absorb resonantly alternating magnetic fields with specific frequencies. In the present paper, a review is made about animal magnetoreception and the effects of alternating magnetic fields in living beings. It is suggested how alternating magnetic fields can interfere in the magnetic alignment of animals and a general conclusion is obtained: alternating magnetic field pollution can affect the magnetic sensibility of animals.

  18. Fa-fa-fa-fa, de doo doo doo, de da da da, sha la la la lee : What is the optimal syllable in improvised singing?

    NARCIS (Netherlands)

    van Eerten, Laura; Gilbers, Dicky; Lowie, Wander; Kager, René; Grijzenhout, Janet; Sebregts, Koen

    2014-01-01

    The aim of this paper is to describe and account for the optimal syllable structure in improvised singing without lyrics. Improvised singing has an overall relaxed character and it is abstracted from meaning. Furthermore, singing in general involves an exaggerated articulation of speech sounds.

  19. MAGNET

    CERN Multimedia

    B. Curé

    2013-01-01

    The magnet is fully stopped and at room temperature. The maintenance works and consolidation activities on the magnet sub-systems are progressing. To consolidate the cryogenic installation, two redundant helium compressors will be installed as ‘hot spares’, to avoid the risk of a magnet downtime in case of a major failure of a compressor unit during operation. The screw compressors, their motors, the mechanical couplings and the concrete blocks are already available and stored at P5. The metallic structure used to access the existing compressors in SH5 will be modified to allow the installation of the two redundant ones. The plan is to finish the installation and commissioning of the hot spare compressors before the summer 2014. In the meantime, a bypass on the high-pressure helium piping will be installed for the connection of a helium drier unit later during the Long Shutdown 1, keeping this installation out of the schedule critical path. A proposal is now being prepared for the con...

  20. MAGNET

    CERN Multimedia

    B. Curé

    MAGNET During the winter shutdown, the magnet subsystems went through a full maintenance. The magnet was successfully warmed up to room temperature beginning of December 2008. The vacuum was broken later on by injecting nitrogen at a pressure just above one atmosphere inside the vacuum tank. This was necessary both to prevent any accidental humidity ingress, and to allow for a modification of the vacuum gauges on the vacuum tank and maintenance of the diffusion pumps. The vacuum gauges had to be changed, because of erratic variations on the measurements, causing spurious alarms. The new type of vacuum gauges has been used in similar conditions on the other LHC experiments and without problems. They are shielded against the stray field. The lubricants of the primary and diffusion pumps have been changed. Several minor modifications were also carried out on the equipment in the service cavern, with the aim to ease the maintenance and to allow possible intervention during operation. Spare sensors have been bough...

  1. MAGNET

    CERN Multimedia

    Benoit Curé

    2010-01-01

    The magnet worked very well at 3.8 T as expected, despite a technical issue that manifested twice in the cryogenics since June. All the other magnet sub-systems worked without flaw. The issue in the cryogenics was with the cold box: it could be observed that the cold box was getting progressively blocked, due to some residual humidity and air accumulating in the first thermal exchanger and in the adsorber at 65 K. This was later confirmed by the analysis during the regeneration phases. An increase in the temperature difference between the helium inlet and outlet across the heat exchanger and a pressure drop increase on the filter of the adsorber were observed. The consequence was a reduction of the helium flow, first compensated by the automatic opening of the regulation valves. But once they were fully opened, the flow and refrigeration power reduced as a consequence. In such a situation, the liquid helium level in the helium Dewar decreased, eventually causing a ramp down of the magnet current and a field...

  2. MAGNET

    CERN Multimedia

    Benoit Curé.

    The magnet operation restarted end of June this year. Quick routine checks of the magnet sub-systems were performed at low current before starting the ramps up to higher field. It appeared clearly that the end of the field ramp down to zero was too long to be compatible with the detector commissioning and operations plans. It was decided to perform an upgrade to keep the ramp down from 3.8T to zero within 4 hours. On July 10th, when a field of 1.5T was reached, small movements were observed in the forward region support table and it was decided to fix this problem before going to higher field. At the end of July the ramps could be resumed. On July 28th, the field was at 3.8T and the summer CRAFT exercise could start. This run in August went smoothly until a general CERN wide power cut took place on August 3rd, due to an insulation fault on the high voltage network outside point 5. It affected the magnet powering electrical circuit, as it caused the opening of the main circuit breakers, resulting in a fast du...

  3. Study on magnetization reversal behavior for annealed Nd2Fe14B/α-Fe nancomposite alloys

    Institute of Scientific and Technical Information of China (English)

    张朋越; 泮敏翔; 葛洪良; 岳明; 刘卫强

    2013-01-01

    Effect of thermal annealing on the magnetization reversal behavior ofα-Fe/Nd2Fe14B alloys was investigated. A drastic in-crease of the remanence Mr from 0.67 up to 0.87 T and remanence ratio Mr/Ms from 0.66 up to 0.76, respectively, was observed in theα-Fe/Nd2Fe14B alloys annealed at 610 oC as compared with the as-quenched sample. Whereas the further annealing at 680 oC resulted in a strong increase of the corecivity Hc as high as 491 kA/m but a slight decrease in Mr. The analysis result of the magnetization re-versal behavior showed that the maximum value of the integrated recoil loop area about 1.58 kJ/m3 was obtained in theα-Fe/Nd2Fe14B alloys at the annealing temperature of 610 oC, significantly lower than other annealed samples. This indicated a sig-nificant advantage for the application of this material as permanent magnets in electrical machines and generators due to a low energy loss.

  4. Dynamic Monte Carlo simulation on behavior of phase transition of a random magnetic system in finite observation time

    Energy Technology Data Exchange (ETDEWEB)

    Kitazaki, Tamotsu; Kato, Tomohiko, E-mail: katou@fit.ac.jp

    2014-03-15

    Random magnets generally exhibit gradual phase transitions more or less. The origin of the phenomena has been controversial for a long time: intrinsic phenomena of disordered magnets or non-equilibrium effect due to finite observation time. We now support the latter, but there have not been clear evidences experimentally and theoretically. We show that the behavior of phase transition of a simple random magnetic system differs in the observation time by using a dynamic Monte Carlo simulation. The target of the simulation is experiments of the line width of NMR spin-echo spectra, a type of the order parameter, on Mn{sub x}Cd{sub 1−x} (HCOO){sub 2}·2(NH{sub 2})2CO. The calculated results indicate that, as the averaging time becomes shorter, the phase transition becomes more gradual. This tendency is most pronounced around the percolation concentration. The calculated results coincide well with the characteristic features of the experimental results. This coincidence supports that the smearing behavior of the order parameter is a non-equilibrium effect, though Ising model employed in the simulation is different with Heisenberg system of the target substance.

  5. Synthesis, Investigation on Structural and Magnetic Behaviors of Spinel M-Ferrite [M = Fe; Zn; Mn] Nanoparticles from Iron Sand

    Science.gov (United States)

    Bahtiar, S.; Taufiq, A.; Sunaryono; Hidayat, A.; Hidayat, N.; Diantoro, M.; Mufti, N.; Mujamilah

    2017-05-01

    Spinel M-ferrite [M = Fe; Zn; Mn] nanoparticles were prepared from iron sand using a coprecipitation-sonochemical approach. The purified Fe3O4 from iron sand, ZnCl2 and MnCl2.4H2O, HCl, and NH4OH were used as raw materials. X-Ray Diffractometer (XRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Transmission Electron Microscopy (TEM), and Vibration Sample Magnetometer (VSM) were employed to characterize the crystal structure, functional groups, particle size, morphology, and magnetic behavior of the prepared samples, respectively. From the XRD data analysis, M-ferrite particles exhibited a single phase in spinel structure. Furthermore, the M-ferrite particle increased their lattice parameter and crystal volume tracking the metallic-ionic radii of M. The particle size of the M-ferrites particles varied with M, whereas the biggest and lowest were for Zn and Mn, respectively. Based on the magnetization curve, the M-ferrite nanoparticles tended to perform a superparamagnetic behavior and their saturation magnetization as a function of their M ion and particle size.

  6. Effect of grain size on electric transport and magnetic behavior of strontium hexaferrite (SrFe12O19)

    Science.gov (United States)

    Sahu, Priyanka; Tripathy, Satya Narayan; Pattanayak, Ranjit; Muduli, Rakesh; Mohapatra, Niharika; Panigrahi, Simanchala

    2017-01-01

    Polycrystalline M-type hexagonal strontium hexaferrite (SrFe12O19) was prepared by conventional ceramic route (LG SrM) and auto combustion (SG SrM) method. The single-phase pattern and well grain growth was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The average crystalline size is found to be 41.35 nm in LG SrM, while that of SG SrM is 36.87 nm. In this report, the electric transport behavior of LG SrM and SG SrM (SrFe12O19) was successfully investigated and the analysis is done in the frequency range 100 Hz to 1 MHz at temperature 30-200 °C. The relaxation behavior was examined by considering the impedance and modulus formalism in order to investigate the grain and grain boundary and surface polarization conduction process. The magnetic properties such as saturation magnetization, remanence, coercivity and anisotropy field are calculated from the hysteresis loop measurement. It was found that the saturation magnetization gets increased in LG SrM as compared to SG SrM system while the coercivity of SG SrM is greater than that of LG SrM.

  7. Effect of Zr Addition on the Magnetization Reversal Behavior for α-Fe/Pr2Fe14B Nanocomposite Alloys

    Science.gov (United States)

    Pan, Minxiang; Zhang, Pengyue; Ge, Hongliang; Hong, Zhanglian; Wu, Qiong; Jiao, Zhiwei; Yang, Hangfu

    2011-09-01

    The microstructure and magnetic properties of the Zr-doped α-Fe/Pr2Fe14B nanocomposite magnets prepared by melt-spinning method have been studied by X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and superconducting quantum interference device (SQUID) measurements. The magnetization reversal behavior during the recoil processes of nanocomposite alloys has been investigated by analyzing the hysteresis curves and recoil loops of demagnetization curves. An enhanced magnetic properties has been obtained by the addition of 1 at. % Zr in α-Fe/Pr2Fe14B alloys, where the coercivity Hc increases from 470.7 to 793.2 kA/m, the maximum energy product (BH)max from 66.8 to 90.8 kJ/m3, the remanence ratio Mr/Ms from 0.74 to 0.77. The recoil loop results show that the maximum value of the integrated recoil loop area for 1 at. % Zr doped sample is quietly low of 1.87×10-3, only 1/2 for the Zr-free and 1/3 for 5 at. % Zr doped samples respectively. This result indicates that the 1 at. % Zr doped sample has a lower energy loss, resulting from a low recoverable portion of the magnetization remaining as long as the applied reversal field is below the coercivity Hc. This study provides a promising guideline for the future fabrication of low-energy-loss nanocomposite magnets for electric machines and generators.

  8. Dual behavior of the toroidal magnetic field versus the Rossby wave instability

    Science.gov (United States)

    Gholipour, Mahmoud

    2016-12-01

    The Rossby wave instability (RWI) theory has been considered as one of the top topics in astrophysics due to the fact that it deals with some ambiguous questions, such as the angular momentum transport in the poorly ionized regions of the protoplanetary discs. Based on the theoretical and simulation works, two important factors in the study of the RWI are the viscosity and magnetic field, which are directly connected to each other because the large-scale toroidal magnetic fields are produced by the magnetohydrodynamic (MHD) turbulence. Therefore, it is essential to consider more details about the toroidal magnetic field both in the steady state and perturbation state. In this paper, the role of the strength and gradient of the toroidal magnetic field is investigated on the RWI at the dead zone in the regions of bump. The obtained results show that the gradient of the toroidal magnetic field or its strength have a major role in the RWI occurrence, which have received relatively less attention in previous works. Also, the role of the gradient of the toroidal magnetic field in the RWI is important even in the weak magnetic fields. Hence, the obtained results are very different from what we previously expected, and it seems crucial to research and develop this issue in the theoretical and simulation works. This paper can be helpful on the study of the angular momentum transport in the cold accretion discs, such as accretion discs in quiescent dwarf novae or around the white-dwarf primary.

  9. Effect of magnetic field on the behavior of operantly conditioned mice

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, T..; Williams, M.C.; Ward, S.

    1988-01-01

    Two mice were trained to run a T-shaped maze. One mouse was trained to turn right while the other mouse was trained to turn left. A magnetic field was then set up in the arm of the maze to which the mouse had been trained to turn. The mice were allowed to run the maze and scored on the basis of their correct response. The scores of both mice were significantly lower when the magnetic field was present, thus indicating interference by the magnetic field on their operant conditioning.

  10. Effects of Repetitive Transcranial Magnetic Stimulation on Behavioral Recovery during Early Stage of Traumatic Brain Injury in Rats.

    Science.gov (United States)

    Yoon, Kyung Jae; Lee, Yong-Taek; Chung, Pil-Wook; Lee, Yun Kyung; Kim, Dae Yul; Chun, Min Ho

    2015-10-01

    Repetitive transcranial magnetic stimulation (rTMS) is a promising technique that modulates neural networks. However, there were few studies evaluating the effects of rTMS in traumatic brain injury (TBI). Herein, we assessed the effectiveness of rTMS on behavioral recovery and metabolic changes using brain magnetic resonance spectroscopy (MRS) in a rat model of TBI. We also evaluated the safety of rTMS by measuring brain swelling with brain magnetic resonance imaging (MRI). Twenty male Sprague-Dawley rats underwent lateral fluid percussion and were randomly assigned to the sham (n=10) or the rTMS (n=10) group. rTMS was applied on the fourth day after TBI and consisted of 10 daily sessions for 2 weeks with 10 Hz frequency (total pulses=3,000). Although the rTMS group showed an anti-apoptotic effect around the peri-lesional area, functional improvements were not significantly different between the two groups. Additionally, rTMS did not modulate brain metabolites in MRS, nor was there any change of brain lesion or edema after magnetic stimulation. These data suggest that rTMS did not have beneficial effects on motor recovery during early stages of TBI, although an anti-apoptosis was observed in the peri-lesional area.

  11. Thermal and magnetic behavior of Angustifolia Kunth bamboo fibers covered with Fe{sub 3}O{sub 4} particles

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, S. [Laboratorio de Magnetismo y Materiales Avanzados, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Arias, N.P. [Laboratorio de Materiales Nanoestructurados y Funcionales, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Departamento de Ingenieria Electrica, Electronica y Computacion, Facultad de Ingenieria y Arquitectura, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Giraldo, O., E-mail: ohggiraldo@hotmail.com [Laboratorio de Materiales Nanoestructurados y Funcionales, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia); Rosales-Rivera, A.; Moscoso, O. [Laboratorio de Magnetismo y Materiales Avanzados, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Sede Manizales, Manizales (Colombia)

    2012-08-15

    Several Angustifolia Kunth bamboo fibers, which have been previously treated with an alkaline solution, were coated with magnetite particles. The coating of the fibers was achieved by an in-situ co-precipitation method with Fe{sup 2+} and Fe{sup 3+}in NaOH or NH{sub 4}OH. The fibers were evaluated by chemical analysis using atomic absorption (A.A.) technique, structural characterization by X-ray diffraction (XRD), thermal stability with thermo-gravimetric analysis (TGA) in nitrogen at temperature range between 23 Degree-Sign C and 800 Degree-Sign C and magnetic behavior using vibrating sample magnetometry (VSM) applying a magnetic field between -27 KOe and 27 KOe at room temperature. We found that the thermal stability and magnetization depend of the synthesis method used to cover the Angustifolia Kunth bamboo fibers. In addition, an improved magnetic response was observed when NaOH solution is used to generate the magnetite coating on the fiber surface.

  12. Investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al alloy with Ag and Mn additions

    Energy Technology Data Exchange (ETDEWEB)

    Silva, R.A.G., E-mail: galdino.ricardo@gmail.com [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil); Paganotti, A.; Gama, S. [Departamento de Ciencias Exatas e da Terra-UNIFESP, Diadema-SP (Brazil); Adorno, A.T.; Carvalho, T.M.; Santos, C.M.A. [Instituto de Quimica - UNESP, Araraquara-SP (Brazil)

    2013-01-15

    The investigation of thermal, mechanical and magnetic behaviors of the Cu-11%Al, Cu-11%Al-3%Ag, Cu-11%Al-10%Mn and Cu-11%Al-10%Mn-3%Ag alloys was made using microhardness measurements, differential scanning calorimetry, X-ray diffractometry, scanning electron microscopy, energy dispersion X-ray spectroscopy and magnetic moment change with applied field measurement. The results indicated that the Mn addition changes the phase stability range, the microhardness values and makes undetectable the eutectoid reaction in annealed Cu-11%Al and Cu-11%Al-3%Ag alloys while the presence of Ag does not modify the phase transformation sequence neither microhardness values of the annealed Cu-11%Al and Cu-11%Al-10%Mn alloys, but it increases the magnetic moment of this latter at about 2.7 times and decreases the rates of eutectoid and peritectoid reactions of the former. - Highlights: Black-Right-Pointing-Pointer The microstructure of Cu-Al alloy is modified in the Ag presence. Black-Right-Pointing-Pointer ({alpha} + {gamma}) phase is stabilized down to room temperature when Ag is added to Cu-Al alloy. Black-Right-Pointing-Pointer Ag-rich phase modifies the magnetic characteristics of Cu-Al-Mn alloy.

  13. Indications and complications of tube thoracostomy with improvised underwater seal bottles

    Directory of Open Access Journals (Sweden)

    Sunday A Edaigbini

    2014-01-01

    Full Text Available Background: Tube thoracostomy is a lifesaving and frequently performed procedure in hospitals where the expertise and necessary tools are available. Where the ideal drainage receptacle is unavailable, the underwater seal device can be improvised with bottled water plastic can especially in emergency situations. Aims and Objectives: To determine the frequencies of the various indications and complications of tube thoracostomy with improvised underwater seal. Materials and Methods: A cross-sectional study with a structured proforma was used for assessment over a 3-year period (May 2010-April 2013. The proforma was filled at the time of the procedure by the performing surgeon and patients were followed up with serial chest X-rays until certified cured. A 1.5 L bottled water container was used as the underwater seal receptacle. The data was analysed with SPSS 15 software program. Results: A total of 167 patients were managed. There were 106 (63.5% males and 61 (36.5% females. The mean age was 34.85 ± 16.72 with a range of 1-80 years. The most frequent indication was for malignant/paramalignant effusion, 46 (27.5%. Others were trauma, 44 (26.3%, Parapneumonic effusion, 20 (12%, postthoracotomy 14 (8.4%, empyema thoracis 12 (7.2%, heart disease and tuberculous effusion 11 (6.6% each, pneumothorax 8 (4.8% and misdiagnosis 1 (0.6%. A hundred and one (60.5% of the procedures were performed by registrars, 41 (24.6% by consultants, house officers 15 (9% and senior registrars 10 (6%. The overall complication rate was 16.8% with the more frequent complications been empyema (5.6% and pneumothorax (3.6%. The average duration of tube placement was 13.02 ± 12.362 days and range of 1-110 days. Conclusion : Tube thoracostomy can be a relatively safe procedure with acceptable complication rates even with improvised underwater seal drainage bottles.

  14. The Use of Improvisations Technique to Improve the Speaking Ability of EFL Students

    Directory of Open Access Journals (Sweden)

    Umar Fauzan

    2014-12-01

    Full Text Available The objective of the study was to implement the improvisations technique to improve the student’s speaking ability. In conducting the research, there were two components expected to be improved, they were improving the students’ speaking score and increasing the quality of classroom atmosphere of teaching speaking. This study employed the collaborative classroom action research and it was done in two cycles. Each cycle consisted of four stages: (1 planning, (2 action, (3 observation, and (4 reflection. There were five meetings in each cycle; four meetings for the implementation of improvisations in the teaching of speaking and one meeting for conducting speaking test. The instruments used to collect the data were: (1 observation checklist, (2 field-note, (3 a score sheet, and (4 a questionnaire. The result of the research showed that the criteria of success had been reached. There were two aspects determined as the success criteria of the implementation of improvisations in the teaching of speaking; score improvement and classroom atmosphere. The result of speaking test presented that the students had made some progress, the average scores raised from 2.72 in the pre-test, 3.09 in cycle 1 and 3.76 in cycle 2. These scores indicated an increasing ability from being ‘fair’ to being ‘good’. The classroom atmosphere were also increasing positively; the students were actively involved in the teaching and learning process, indicated by 64% participated in cycle 1 and 73.79% participated in cycle 2. The students were also highly motivated in joining the teaching learning process. They cooperated, asked, responded, and expressed spontaneously.

  15. Indications and Complications of Tube Thoracostomy with Improvised Underwater Seal Bottles

    Science.gov (United States)

    Edaigbini, Sunday A; Delia, Ibrahim Z; Aminu, Muhammad B; Orogade, Abosede A; Anumenechi, Ndubuisi; Aliyu, Ibrahim D

    2014-01-01

    Background: Tube thoracostomy is a lifesaving and frequently performed procedure in hospitals where the expertise and necessary tools are available. Where the ideal drainage receptacle is unavailable, the underwater seal device can be improvised with bottled water plastic can especially in emergency situations. Aims and Objectives: To determine the frequencies of the various indications and complications of tube thoracostomy with improvised underwater seal. Materials and Methods: A cross-sectional study with a structured proforma was used for assessment over a 3-year period (May 2010-April 2013). The proforma was filled at the time of the procedure by the performing surgeon and patients were followed up with serial chest X-rays until certified cured. A 1.5 L bottled water container was used as the underwater seal receptacle. The data was analysed with SPSS 15 software program. Results: A total of 167 patients were managed. There were 106 (63.5%) males and 61 (36.5%) females. The mean age was 34.85 ± 16.72 with a range of 1-80 years. The most frequent indication was for malignant/paramalignant effusion, 46 (27.5%). Others were trauma, 44 (26.3%), Parapneumonic effusion, 20 (12%), postthoracotomy 14 (8.4%), empyema thoracis 12 (7.2%), heart disease and tuberculous effusion 11 (6.6%) each, pneumothorax 8 (4.8%) and misdiagnosis 1 (0.6%). A hundred and one (60.5%) of the procedures were performed by registrars, 41 (24.6%) by consultants, house officers 15 (9%) and senior registrars 10 (6%). The overall complication rate was 16.8% with the more frequent complications been empyema (5.6%) and pneumothorax (3.6%). The average duration of tube placement was 13.02 ± 12.362 days and range of 1-110 days. Conclusion: Tube thoracostomy can be a relatively safe procedure with acceptable complication rates even with improvised underwater seal drainage bottles. PMID:25191098

  16. Being in the zone: physiological markers of togetherness in joint improvisation.

    Science.gov (United States)

    Noy, Lior; Levit-Binun, Nava; Golland, Yulia

    2015-01-01

    Performers improvising together describe special moments of 'being in the zone' - periods of high performance, synchrony, and enhanced sense of togetherness. Existing evidence suggests a possible route for attaining togetherness - interpersonal synchrony, the fine-grained sensory-motor coordination that promotes social connectedness. Here, we investigated the physiological characteristics of togetherness using a practice from theater and dance, the mirror game. Pairs of expert improvisers jointly improvised synchronized linear motion, while their motion tracks and cardiovascular activity were continuously monitored. Players also provided dynamic ratings of togetherness while watching video recordings of their games. We identified periods of togetherness using kinematic and subjective markers and assessed their physiological characteristics. The kinematic and the subjective measures of togetherness showed some agreement, with more extensive game periods being marked by the subjective than the kinematic one. Game rounds with high rates of togetherness were characterized by increased players' cardiovascular activity, increased correlation of players' heart rates (HRs), and increased motion intensity. By comparing motion segments with similar motion intensity, we showed that moments of togetherness in the mirror game were marked by increased players' HRs, regardless of motion intensity. This pattern was robust for the subjectively defined periods of togetherness, while showing a marginal effect for the kinematically defined togetherness. Building upon similar findings in flow research we suggest that the observed increase of players' HRs during togetherness periods in the mirror game might indicate the enhanced engagement and enjoyment reported by performers going into 'the zone.' The suggested approach, combining temporal measurements of kinematic, physiological and subjective responses, demonstrates how the dynamics of spontaneously emerging dyadic states can be

  17. Being in the zone: physiological markers of togetherness in joint improvisation

    Directory of Open Access Journals (Sweden)

    Lior eNoy

    2015-05-01

    Full Text Available Performers improvising together describe special moments of ‘being in the zone’ – periods of high performance, synchrony and enhanced sense of togetherness. Existing evidence suggests ¬a possible route for attaining togetherness - interpersonal synchrony, the fine-grained sensory-motor coordination that promotes social connectedness. Here we investigated the physiological characteristics of togetherness using a practice from theater and dance, the mirror game.Pairs of expert improvisers jointly improvised synchronized linear motion, while their motion tracks and cardiovascular activity were continuously monitored. Players also provided dynamic ratings of togetherness while watching video recordings of their games. We identified periods of togetherness using kinematic and subjective markers and assessed their physiological characteristics. The kinematic and the subjective measures of togetherness showed some agreement, with more extensive game-periods being marked by the subjective than the kinematic one.Game rounds with high rates of togetherness were characterized by increased players’ cardiovascular activity, increased correlation of players’ heart rates, and increased motion intensity. By comparing motion segments with similar motion intensity, we showed that moments of togetherness in the mirror game were marked by increased players’ heart rates, regardless of motion intensity. This pattern was robust for the subjectively defined periods of togetherness, while showing a marginal effect for the kinematically defined togetherness. Building upon similar findings in flow research we suggest that the observed increase of players’ heart rates during togetherness periods in the mirror game might indicate the enhanced engagement and enjoyment reported by performers going into ‘the zone’. The suggested approach, combining temporal measurements of kinematic, physiological and subjective responses, demonstrates how the dynamics of

  18. Video Conferencing for Opening Classroom Doors in Initial Teacher Education: Sociocultural Processes of Mimicking and Improvisation

    Directory of Open Access Journals (Sweden)

    Wiesemes, Rolf

    2010-01-01

    Full Text Available In this article, we present an alternative framework for conceptualising video-conferencing uses in initial teacher education and in Higher Education (HE more generally. This alternative framework takes into account the existing models in the field, but – based on a set of interviews conducted with teacher trainees and wider analysis of the related literature – we suggest that there is a need to add to existing models the notions of ‘mimicking’ (copying practice and improvisation (unplanned and spontaneous personal learning moments. These two notions are considered to be vital, as they remain valid throughout teachers’ careers and constitute key affordances of video-conferencing uses in HE. In particular, we argue that improvisational processes can be considered as key for developing professional practice and lifelong learning and that video-conferencing uses in initial teacher education can contribute to an understanding of training and learning processes. Current conceptualisations of video conferencing as suggested by Coyle (2004 and Marsh et al. (2009 remain valid, but also are limited in their scope with respect to focusing predominantly on pragmatic and instrumental teacher-training issues. Our article suggests that the theoretical conceptualisations of video conferencing should be expanded to include elements of mimicking and ultimately improvisation. This allows us to consider not just etic aspects of practice, but equally emic practices and related personal professional development. We locate these arguments more widely in a sociocultural-theory framework, as it enables us to describe interactions in dialectical rather than dichotomous terms (Lantolf & Poehner, 2008.

  19. The growth of a single crystal of Sr3CuIrO6 and its magnetic behavior compared to polycrystals

    Indian Academy of Sciences (India)

    Asad Niazi; P L Paulose; E V Sampathkumaran; Ute Ch Rodewald; W Jeitschko

    2002-05-01

    We have grown single crystals of the psuedo-one-dimensional compound Sr3CuIrO6, a K4CdCl6-derived monoclinic structure with Cu–Ir chains along the [101] direction. We present the ac and dc magnetization behavior of the single crystals in comparison with that of the polycrystalline form reported earlier. There is a distinct evidence for at least two magnetic transitions, at 5 K (1) and 19 K (2), with different relative magnitudes in the single and polycrystals. The low temperature magnetic relaxation behavior of both the forms is found to be widely different, exhibiting unexpected time dependence.

  20. Magnetic behavior in Cr2@Gen (1≤n≤12) clusters: A density functional investigation

    Science.gov (United States)

    Dhaka, Kapil; Trivedi, Ravi; Bandyopadhyay, Debashis

    2014-04-01

    With a goal to produce magnetic moment in Cr2 Doped Gen clusters which will be useful for practical applications, we have considered the structure and magnetic properties of Pure Germanium clusters and substitutionally doped it with Cr dimer to produce Cr2@Gen clusters. As the first step of calculation, geometrical optimizations of the nanoclusters have been done. These optimized geometries have been used in calculate the average binding energy per atom (BE), HOMO-LUMO gap and hence the relative stability of the clusters. These parameters have been demonstrated as structural and electronic properties of the clusters. Gap between highest occupied molecular orbital and lowest unoccupied molecular orbital indicate cluster to be a potential motif for generating magnetic cluster assembled materials. Based on these values a comparative study on different sized clusters has been done in order to understand the origin of structures, electronic and magnetic properties of Cr2@Gen nanoclusters.