The Relationship Between Crystal Structure and Performance as Optical Recording Media In Te-Ge-Sb Thin Films

1991 ◽  
Vol 230 ◽  
Author(s):  
D. Strand ◽  
J. Gonzalez-Hernandez ◽  
B. S. Chao ◽  
S. R. Ovshinsky ◽  
P. Gasiorowski ◽  
...  

AbstractThe crystallization properties of Te-Ge and Te-Ge-Sb alloys prepared by thermal evaporation were analyzed using various characterization techniques. Similar to previous results, our data for Te-Ge shows that alloys that deviate slightly from Te50Ge50 stoichiometry show drastically slower crystallization kinetics. Raman spectroscopy and x-ray diffraction show that alloys having non-stoichiometric atomic ratios phase separate during crystallization into a Te50Ge50 phase plus pure crystalline tellurium or germanium. It is this relatively slow process of phase segregation which limits the crystallization rate. Phase segregation during crystallization of non-stoichiometric Te-Ge can be eliminated by adding antimony to samples having a tellurium concentration of from 45 to 55 atomic percent over a wide range of Ge:Sb ratios. These alloys can have laser induced crystallization times of less than 50 nsec. The thermal crystallization temperature is reduced only slightly when antimony is substituted for germanium.

2018 ◽  
Vol 19 (2) ◽  
pp. 407-452 ◽  
Author(s):  
Eugénia Pedro ◽  
João Leitão ◽  
Helena Alves

Purpose The purpose of this paper is to determine the predominant classification of intellectual capital (IC), in terms of components, using the literature of reference on the relationship between IC and performance and considering multi-dimensional analysis axes (MAAs): organisational, regional and national. Design/methodology/approach A systematic literature review (SLR) is presented focussing on empirical studies on IC published in the period 1960-2016. A protocol for action is defined and a research question is raised, gathering data from the databases of: Web of Science, Scopus and Google Scholar. A social network analysis is also provided to determine the type of networks embracing groups, IC individual components and performance type. Findings Of the 777 papers included in the SLR, 189 deal with the relationship between IC and performance. The paper highlights the greater development of empirical studies starting from 2004; the organisational MAA is the most studied. The most frequently used groups of components in studies dealing with IC’s influence on performance corresponds to a triad of human capital; structural (organisational or process) capital; and relational (social or customer) capital, which determine positively the performance of organisations/regions/countries, but their influence is not linear and depends on various factors associated with the context and surrounding environment. Practical implications This study has wide-ranging implications for politicians/governments, managers and academics, providing empirical evidence about the relationships between the components of IC and performance, by MAAs, and a global vision and better understanding of how those IC components have developed and how they are related to performance. Originality/value Due to the high number of references covering a wide range of disciplines and the various dimensions (e.g. organisational, regional and national) that form IC, it becomes fundamental to carry out an SRL and systematise its MAAs to deepen knowledge about what has been discovered/developed in this domain, in terms of empirical studies, in order to situate the topic in a wider theoretical-practical context. The paper is exceptionally wide-ranging, covering the period 1960-2016. It is one of the first clarifying studies on systemisation of the literature on IC, by MAA, and an in-depth study of IC’s impact on the performance of organisations/regions and countries which may serve as a guideline for future studies using the taxonomy proposed.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2507
Author(s):  
Jinxian Zhai ◽  
Hanpeng Zhao ◽  
Xiaoyan Guo ◽  
Xiaodong Li ◽  
Tinglu Song

The relationship between temperature and the mechanical properties of an end cross-linked equal molar random copolyether elastomer of 3,3-bis(azidomethyl)oxetane and tetrahydrofuran (P(BAMO-r-THF)) was investigated. During this investigation, the performances of two P(BAMO-r-THF) elastomers with different thermal histories were compared at different temperatures. The elastomer as prepared at 20 °C (denoted as S0) exhibited semi-crystallization morphology. Wide angle X-ray diffraction analysis indicated that the crystal grains within elastomer S0 result from the crystallization of BAMO micro-blocks embedded in P(BAMO-r-THF) polymeric chains, and the crystallinity is temperature irreversible under static conditions. After undergoing a heating-cooling cycle, this elastomer became an amorphous elastomer (denoted as S1). Regarding mechanical properties, at 20 °C, break strains and stresses of 315 ± 22% and 0.46 ± 0.01 MPa were obtained for elastomer S0; corresponding values of 294 ± 6% and 0.32 ± 0.02 MPa were obtained for elastomer S1. At −40 °C, these strains and stresses simultaneously increased to 1085 ± 21% and 8.90 ± 0.72 MPa (S0) and 1181 ± 25% and 10.23 ± 0.44 MPa (S1), respectively, owing to the strain-induced crystallization of BAMO micro-blocks within the P(BAMO-r-THF) polymeric chains.


2021 ◽  
Vol 12 ◽  
Author(s):  
Mami Shibata ◽  
Julius Burkauskas ◽  
Artemisa R. Dores ◽  
Kei Kobayashi ◽  
Sayaka Yoshimura ◽  
...  

Introduction: Physical distancing under the coronavirus disease 2019 (COVID-19) pandemic had a significant impact on lifestyles, including exercise routines. In this study, we examined the relationship between mental health and addictive behaviors, such as excessive exercise and the use of image and performance enhancing drugs (IPEDs) across 12 sport disciplines.Materials and methods: A large cross-sectional sample of the adult population (N = 2,295) was surveyed. The mean age was 33.09 (SD = 11.40). The number of male participants was 668 (30.0%). The use of IPEDs was assessed in conjunction with psychometric measures such as the Exercise Addiction Inventory (EAI) and the Appearance Anxiety Inventory (AAI). The participants were grouped into activity group (AG) and non-activity group (NAG) according to the presence or absence of their exercise habits. The results were compared between these groups, as well as across sport disciplines, while taking into account the relationship between different psychological measures and IPEDs consumption.Results: The frequency of IPEDs use was higher among AG (34.6%) than NAG (14.6%), although AG participants reported less history of addictions (7.1%) than NAG (11.8%). The logistic regression analysis revealed that scores equal to or above cutoff points, in both the EAI and AAI, predicted the IPEDs use. Regarding the differences across the various sport disciplines, those who were involved in practicing Weight Lifting and Cross Fit were found to be more at risk of excessive exercising and more inclined to use a wide range of IPEDs.Conclusions: Although exercise could help to increase well-being and prevent addictions during the COVID-19 pandemic, our results show that those in the AG are particularly vulnerable to excessive IPEDs use. Sport disciplines associated with higher EAI and AAI scores have also shown a higher tendency to excessive IPEDs use. Furthermore, the factor of having above the cutoff scores in EAI or AAI in each sport could indicate larger IPEDs consumption regardless of the discipline. In light of the current findings, it is necessary to better define the “non-excessive” levels of exercise in various sport disciplines and an adequate intake of IPEDs to ensure the safety and well-being of people during a pandemic.


The very concept of human rights implies governmental accountability. To ensure that governments are held accountable for their treatment of citizens and others, the United Nations has established a wide range of mechanisms to monitor compliance, and to seek to prevent as well as respond to violations. The panoply of implementation measures that the UN has taken since 1945 has resulted in a diverse and complex set of institutional arrangements, the effectiveness of which varies widely. Inevitable instances of politicization and the hostile or ambivalent attitude of most governments has often endangered the fragile progress made on the more technical fronts. In addition, there are major problems of underfunding and insufficient expertise. The complexity of these arrangements and the difficulty in evaluating their impact makes a comprehensive guide of the type provided here all the more indispensable. This book critically examines the functions, procedures, and performance of each of the major UN organs dealing with human rights, including the Security Council and the International Court of Justice as well as the more specialized bodies monitoring the implementation of human rights treaties. Significant attention is devoted to the considerable efforts at reforming the UN’s human rights machinery, as illustrated most notably by the creation and operation of the Human Rights Council. The book also looks at the relationship between the various bodies and the potential for major reforms and restructuring.


2020 ◽  
Vol 19 (19) ◽  
pp. 139-150
Author(s):  
Oleksandr Pastukhov

Background. The article deals with the interaction of the constructive evolution of the instrument and the development of bassoon performing of the 16–17 centuries. The aesthetics of that time was associated with the search for new expressive means, realization of which could be ensured by new instruments with rich and expressive sound. One of such instruments is bassoon; it was during the Baroque era when the bassoon took its shape and the sound image we know today. Thanks to technical evolution, the instrument acquired new artistic capabilities and new sound quality. A new repertoire was formed; bassoon became the part of such instrumental genres as sonata and concerto, it was firmly fixed in the score of the symphony orchestra. In music science, there are a number of studies devoted to wind instruments, the most significant of which are researches by G. Abadzhyan, V. Apatskiy L. Belenov, V. Berezin, V. Bohdanov, N. Volkov, V. Gromchenko, Yu. Dolzhikov, V. Kachmarchyk, V. Lebedev, V. Popov, I. Pushechnikov, Yu. Usov, and A. Kiziliayev. There are works, which focus on the bassoon, its history, expressive and technical capabilities (G. Abadzhyan, V. Apatskiy, V. Bubnovich, N. Karaulovsky, S. Levin, V. Leonov, V. Popov, V. Starko, Anthony Baines). It is worth noting the rather important and comprehensive work by V. Apatskiy “Bassoon from A to Z”. There are numerous scientific publications of international woodwind performers associations, such as the International Double Reed Society, the Australian double reed community, the British double reed community, the Japan bassoon society, the Finnish double reed community. The purpose of the article is to reveal the specifics of the relationship between the structural improvements of the bassoon and the performance on the bassoon in the period of 16–17 centuries. Achieving this goal will help to perform tasks such as a historical overview of the development of the bassoon in the Baroque era and identify the relationship between constructive changes, artistic possibilities, repertoire potential (including the genre palette of the instrument) and composer work for the bassoon of this period. The presented article is a material used in the candidate’s dissertation, which is devoted to a wide range of issues of performance on the bassoon from the origins to the present. Methodology. The main research methods are historical, organological and performing. The historical method is associated with the characterization of the historical conditions of origin and development of the bassoon; the organological method is necessary to establish the connection between the constructive changes of the instrument with the new quality of its sound; the performing method helps to reveal new tendencies in bassoon performance of the 16–17 centuries from the new repertoire to the functional purpose of the instrument. Research results. Around the middle of the 17th century, fundamental changes occurred in the construction of the bassoon. They were caused by the need to regulate the overall tuning system of the instrument in such a way that it could participate in joint music-making with other instruments, as well as by the desire to make the instrument more portable. At the turn of the 16–17 centuries, in the process of bassoon chromatization as the result of complication of composer creativity, fundamental changes were made in the design of the instrument: new “chromatic” holes and valves, as well as fork fingering appeared. It was all connected with the formation of certain musical and aesthetic needs and developed along with them. So, the evolution of the bassoon 16–17 centuries led to such qualitative changes in the sound of the instrument as: softness of the tone, pitch control, expansion of the working range, great power of sound, ease of playing the instrument. The above-mentioned factors entailed fundamental changes in the composers’ attitude towards the instrument. The bassoon enters a more complex functional level in the works of various music genres (interlude to the comedy “La Pellegrina” by Girolamo Bargalia, “Sacrae symphoniae” by Giovanni Gabrieli, “Messa a 4 voci et Salmi” by C. Monteverdi, “Fantasy for basso continuo” by Bartolome deSelma-i-Salaverde, sonata “Lamonica” by PhilipFriedrich Bodekher, nine sonatas for solo bassoon and basso continuo by Giovanni Antonio Bertoli, sonata for two bassoons by Philipp Friedrich Buchner, opera “Il pomo d’oro” by Antonio Cesti, singspiel “Seelewig” by Sigmund Theophil Staden). The role of Antonio Vivaldi in the formation of the concerto, including concerto for bassoon, is difficult to overestimate, and thirty-nine Vivaldi’s concertos for bassoon are evidence of that. The creative work of Antonio Vivaldi affected Johann Sebastian Bach, who wrote bassoon parts in his works of different genres. George Philippe Telemann, Bach’s contemporary, is known for a large number of pieces with bassoon parts. Conclusions. Constructive changes resulted in the arrival of the bassoon to a new timbre, figurative-intonational, genre, and performance level. Meanwhile, there is a linear rather than reciprocal relationship between the above-mentioned levels. On the one hand, there is a direct dependence in the evolution of bassoon performance: new constructive features – technical capabilities of the instrument – more individual timbre character – new expressive possibilities – solo parts – solo pieces. On the other hand, all this creates new requirements both for the performer and for the instrument, which brings the situation back to the need for further search. The results of this research can be used in further studies devoted to the history and theory of bassoon performance in the historical, organological and genre-stylistic directions.


2020 ◽  
pp. 009524432092857
Author(s):  
Nureeyah Jehsoh ◽  
Indra Surya ◽  
Kannika Sahakaro ◽  
Hanafi Ismail ◽  
Nabil Hayeemasae

Natural rubber (NR) is known as hydrophobic material and is incompatible with hydrophilic filler such as halloysite nanotubes (HNTs). To overcome this obstacle, the compatibilizer is a material of choice to incorporate in such compound. In this study, bio-based compatibilizer was used which was prepared by modification of palm stearin. The presence of special functionalities of modified palm stearin (MPS) was confirmed by Fourier transform infrared (FTIR) analysis. It was then varied from 0.5 phr to 2 phr to the NR matrix. Here, the properties were evaluated through the mechanical properties with special attention to the relationship between their reinforcement and crystallization behavior after stretching. It was found that the addition of MPS significantly enhanced the modulus, tensile strength, and tear strength of the composites. This clearly corresponded to interaction between NR and HNT promoted by MPS. The FTIR spectrum, X-ray diffraction patterns, and scanning electron microscopy images were also utilized to verify the behavior of MPS in the NR/HNT composites. As for the crystallization of the composites, the results obtained from stress–strain curves are in very good agreement to the outputs observed by the synchrotron wide-angle X-ray scattering. This corresponding interaction of MPS has greatly influenced on assisting the strain-induced crystallization of composites.


1992 ◽  
Vol 36 ◽  
pp. 197-202
Author(s):  
Po-Wen Wang

In recent years, the microstructure of Co-based alloy magnetic thin film disks has been studied extensively by using a conventional x-ray diffraction (XRD) technique(1-4). Efforts to understand the relationship between the microstructure and the magnetic properties of disk had been limited due to the lack of depth resolution in the conventional theta-2theta scanning technique. In this paper, a fixed 0.5 degree of grazing incidence(5) 2-theta scan X-ray diffraction (GIXRD) technique was used to characterize the thin film disk microstructure and therefore to correlate with the magnetic properties.


2004 ◽  
Vol 77 (2) ◽  
pp. 317-335 ◽  
Author(s):  
Shigeyuki Toki ◽  
Igors Sics ◽  
Shaofeng Ran ◽  
Lizhi Liu ◽  
Benjamin S. Hsiao ◽  
...  

Abstract In-situ synchrotron wide-angle X-ray diffraction (WAXD) studies and simultaneous measurements of stress and strain during uniaxial stretching of various vulcanized rubbers were carried out (at room temperature and 0°C) to reveal the strain-induced molecular orientation and crystallization relationships. Rubbers evaluated included natural rubber (NR), synthetic poly-isoprene rubber (IR), poly-cis-1,4-butadiene rubber (BR) and butyl rubber (IIR). Some universal features were observed in these systems: (i) At high strains (> 5.0), the majority of the chains (up to 50 ≈ 75%) in natural and synthetic rubbers remained in the un-oriented amorphous state with only a small amount of crystalline fraction formed (10–20%). The rest of the chains were in the oriented amorphous state. (ii) During deformation, the oriented amorphous chains acted as precursors to strain-induced crystallization. A network of micro-fibrillar crystallites is formed within the closely populated vulcanization points, leading to the enhancement of mechanical properties at high strains. Different rubbers exhibited different behaviors during strain-induced crystallization. For example, poly-isoprenes (NR and IR vulcanized with sulfur and peroxide) showed strain-induced crystallization at a low strain of 2.5, resulting in larger crystalline but smaller oriented amorphous fractions. In contrast, BR and IIR crystallized at a higher strain of 4.0 lead to higher molecular orientation, higher oriented amorphous, but smaller crystalline fractions. The relationship between the molecular orientation and crystallization in strained rubber depends on the intrinsic crystallizability of the chains and the topology of the crosslinked network.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2587
Author(s):  
Iurii Vozniak ◽  
Ramin Hosseinnezhad ◽  
Jerzy Morawiec ◽  
Andrzej Galeski

Polymer–polymer systems with special phase morphology were prepared, leading to an exceptional combination of strength, modulus, and ductility. Two immiscible polymers: poly(ε-caprolactone) (PCL) and polyhydroxyalkanoate (PHA) were used as components for manufacturing a nanoblend and a nanocomposite characterized by nanodroplet-matrix and nanofibril-matrix morphologies, respectively. Nanofibrils were formed by high shear of nanodroplets at sufficiently low temperature to stabilize their fibrillar shape by shear-induced crystallization. The effects of nanodroplet vs. nanofiber morphology on the tensile mechanical behavior of the nanocomposites were elucidated with the help of in situ 2D small-angle X-ray scattering, microcalorimetry and 2D wide-angle X-ray diffraction. For neat PCL and a PCL/PHA blend, the evolution of the structure under uniaxial tension was accompanied by extensive fragmentation of crystalline lamellae with the onset at strain e = 0.1. Limited lamellae fragmentation in the PCL/PHA composite occurred continuously over a wide range of deformations (e = 0.1–1.1) and facilitated plastic flow of the composite and was associated with the presence of a PHA nanofiber network that transferred local stress to the PCL lamellae, enforcing their local deformation. The PHA nanofibers acted as crystallization nuclei for PCL during their strain-induced melting–recrystallization.


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