bluuebunny/crossref_metadata_2025 huggingface dataset:
Análise de Repositórios de REAs em Relação ao Uso dos Padrões de Linked Open Data
Authors: Paula Luciano Bernardes de , Deus William Simão de , Barbosa Ellen Francine
Published: November 2020

Recursos Educacionais Abertos (REAs) são uma parte muito importante para o conceito de Educação Aberta. Esses recursos são compartilhados de forma aberta, possibilitando seu uso, reuso e adaptação de forma livre. Um ponto importante para tornar eficiente a busca por REAs em repositórios pela Web é como o metadado desses recursos devem expor dados sobre o mesmo. Uma iniciativa global para definir padrões para propiciar acesso e interligação de dados abertos na Web é o Linked Open Data. Este artigo apresenta uma análise de repositórios de REAs a respeito do uso dos padrões de LOD em seus metadados. Ao final é feita uma discussão sobre os resultados dessa análise e as vantagens dessa adoção pelos repositórios.
Contextos de Aprendizagem para Interações Contingentes em Fóruns de Discussão Online: uma Investigação à Luz da Etnografia Interacional
Authors: David Priscila Barros , Green Judith L. , Santos Vanessa Ellen Cacau
Published: November 2020

Este estudo tem como objetivo identificar e caracterizar contextos de aprendizagem favoráveis à implementação de interações contingentes em um fórum de discussão de um Curso de Formação Inicial de Tutores a Distância. A abordagem Etnográfica Interacional que norteou esta pesquisa estabelece quatro princípios operativos que guiam as decisões e ações do etnógrafo no campo de pesquisa. Tais princípios promoveram uma compreensão mais ampla sobre os contextos de aprendizagem no fórum. Os resultados do estudo apontam, principalmente: a fragilidade da representação da interação na ferramenta fórum investigada e o surgimento de uma nova unidade de análise para o estudo de interações contingentes: o fórum como um todo.
For whom should we gamify? Insights on the users intentions and context towards gamification in education
Authors: Toda Armando , Pereira Filipe Dwan , Klock Ana Carolina Tomé , Rodrigues Luiz , Palomino Paula , Oliveira Wilk , Oliveira Elaine Harada Teixeira , Gasparini Isabela , Cristea Alexandra Ioana , Isotani Seiji
Published: November 2020

Gamification design in educational environments is not trivial and many variables need to be considered to achieve positive outcomes. Often, educators and designers do not know when the students intentions on the use of gamified environments might influence their experience. Based on this premise, this paper describes an exploratory study on the users intention to use gamification, focusing on its influence in the field of education. We conducted a survey study with participants (N=1.692) and analysed their answers using unsupervised data mining techniques. As a result, we obtained empirical evidence showing that demographic and contextual variables influence (positively and negatively) peoples intention to use gamification. This evidence can support designers and educators better understand whether and when they should or should not gamify a learning environment.
Sozialökologischer Umbau der Weltwirtschaft oder Handelskrieg mit anderen Mitteln?
Authors: Butollo Florian
Published: November 2020

Die Engpässe bei Atemschutzmasken und medizinischer Ausrüstung im Laufe der Covid-19-Krise haben eine grundlegende Diskussion über die Krisenanfälligkeit globaler Wertschöpfungsketten angestoßen. Hierbei stehen Forderungen nach einer Rückverlagerung der Fertigung (Reshoring), einer Diversifizierung der Lieferketten und dem Aufbau von Lagerbeständen bzw. Sicherheitspuffern im Mittelpunkt. Der Beitrag hinterfragt die Grundannahmen dieser Debatten und zeigt, dass die wirtschaftlichen Schwierigkeiten in Folge der Covid-19-Krise nicht primär Resultat exzessiver Auslandsabhängigkeit, sondern der von Kostenoptimierungszielen getriebenen engen Taktung und komplexen Verzweigung von Wertschöpfungsketten ist. Antworten auf die Probleme mit der gegenwärtigen Struktur globaler Wertschöpfungsketten sollten dieses Thema in den Kontext der unumgänglichen sozial-ökologischen Transformation der Wirtschaftsweise stellen. Dies beinhaltet vor allem eine erhöhte gesellschaftliche Resilienz durch die Stärkung fundamentaler Güter und Dienstleistungen in Bereichen wie Wohnen, Energie, Wasser, Gesundheit, Bildung und Pflege.
Leben machen und sterben lassen: Die Politik mit der Vulnerabilität
Authors: Lessenich Stephan
Published: November 2020

In der Corona-Krise hat der Begriff der „Vulnerabilität“ bzw. die Rede von „vulnerablen Gruppen“ Eingang in den öffentlichen Diskurs gefunden. Entgegen der verbreiteten Ansicht, dass diese semantische Konjunktur auch die Durchsetzung einer neuartigen „Politik für das Leben“ anzeigt, argumentiert der Beitrag, dass sich das Corona-Krisenmanagement vielmehr durch seine soziale Selektivität und eine Hierarchisierung des Lebenswerten auszeichnet. Während eine alternative Corona-Politik im Sinne des Vulnerabilitäts-Konzepts Robert Castels stattdessen auf eine institutionelle Bekämpfung sozialer Gefährdetheit zielen würde, setzt eine politische Strategie im Geiste von Judith Butlers Vulnerabilitäts-Verständnis eher auf die soziale Sensibilisierung für die grundlegende Verwundbarkeit des Körpers und des Lebens. Erst die Akzeptanz dieser allgemeinen sozialen Tatsache kann demnach die Basis für eine kollektive Bearbeitung auch der konkreten Vulnerabilitäten unterschiedlicher Personen und sozialer Positionen bilden.
Was ist wichtig? Die Corona-Pandemie als Impuls zur Neubewertung systemrelevanter Sektoren
Authors: Lübker Malte , Zucco Aline
Published: November 2020

Um den weiteren Ausbruch des Corona-Virus in Deutschland zu verhindern, wurde im März 2020 das soziale und wirtschaftliche Leben erheblich eingeschränkt. Lediglich Beschäftigte in den systemrelevanten Sektoren waren dazu angehalten, ihrer Erwerbstätigkeit weiter nachzugehen, da sie den Erhalt der kritischen In­frastruktur sicherten. In diesem Beitrag gehen die Autoren der Beschäftigung und insbesondere der Entlohnung in diesen Sektoren nach. Sie stützen ihre Analyse auf einen Linked-Employer-Employee-Datensatz (LIAB) des IAB. Mittels deskriptiver Statistiken und Regressionen zeigen sie zunächst, dass die Beschäftigten in diesen Sektoren sich deutlich von sonst hoch angesehenen Beschäftigtengruppen unterscheiden, denn dort sind vor allem teilzeitbeschäftigte Frauen und Personen mit fachlichen Tätigkeiten beschäftigt. Weiterhin zeigt sich, dass die Entlohnung in diesen Sektoren durchaus heterogen ist: Denn während in einigen systemrelevanten Branchen weit überdurchschnittlich entlohnt wird, liegen die Löhne anderer systemrelevanter Sektoren weiter unter dem Schnitt. Dieses Resultat ist stabil, wenn für Humankapital-Variablen kontrolliert wird. Die angesichts der Krisensituation offenbarte Relevanz dieser Tätigkeiten verdeutlicht die Notwendigkeit einer Neubewertung dieser Sektoren.
Rechtliche Wechselwirkungen
Authors: Vollgraf Ingo
Published: November 2020

Nebentätigkeiten von Arbeitnehmerinnen und Arbeitnehmern unterliegen bestimmten rechtlichen Anforderungen. Insbesondere während der Coronavirus-Pandemie kommen weitere Aspekte dazu, die beachtet sein wollen.
Unterschätztes Instrument
Authors: Schmotz Torsten
Published: November 2020

Fördermittel verfügen über ein großes Volumen, stellen aber immer noch ein unterschätztes Fundraising-Instrument dar.
Neues Denken erwünscht
Authors: Riedl Anton Konrad
Published: November 2020

Die Bedeutung des Qualitätsmanagements in Sozialunternehmen hat durch die Corona-Krise weiter zugenommen. Ein neues Konzept hebt die Bedeutung von Prozessen für die Effektivität und Effizienz von Dienstleistungsorganisationen hervor.
Scientific Publishing in Biomedicine: How to Choose a Journal?
Authors: Bahadoran Zahra , Mirmiran Parvin , Kashfi Khosrow , Ghasemi Asghar
Published: November 2020

: Publishing in peer-reviewed high-quality journals is a gold standard method for disseminating scientific work. Choosing the right journal is one of the most important and difficult aspects of publishing research results. Submitting to an inappropriate journal is one of the most common reasons for fast rejection of manuscripts, resulting in time wasted by the authors and journals’ editors. Here, we discuss important factors that should be considered for choosing the right journal to get your work published successfully and effectively. The most important factors for journal targeting are: (1) The journal’s characteristics, including its scientific prestige, performance, publishing model, acceptance possibility, and specialty; (2) the manuscript’s characteristics, including its relevance to the journal’s aim and scope, its intrinsic value, meaning the novelty of the research, soundness of the methodology, potential impact in the field, and its implication; and (3) authors’ priorities and limitations.
The Effectiveness of Group Therapy Based on Mentalization and Dialectical Behavior on Attachment Styles, Social Cognition, Mentalization: A Randomized Controlled Clinical Trial
Authors: Khabir Leila , Mohamadi Nourollah , Rahimi Changiz , Dastgheib Seyed Ali
Published: November 2020

Background: Mentalization-based treatment (MBT) and dialectical behavioral therapy (DBT) are two treatments with a strong theoretical basis for borderline personality disorder (BPD). Objectives: We investigated the structures that influence the process of symptom recovery from the perspective of mentalization-based treatment. Methods: This is a single-blind randomized controlled clinical trial conducted on 60 patients diagnosed with BPD. Data were collected from March 2017 to June 2017 by a psychiatrist in a semi-structured clinical interview. The participants were categorized into intervention and control groups. Before, immediately and two months after the group therapy based on MBT and DBT, the participants were assessed with Revised Adult Attachment Scale (RAAS), Reflective Function Questionnaire for Adult (RFQA), Eye Test-Test Revised Version, Beck Anxiety Inventory (BAI), and Beck Depression Inventory-II (BDI-II). Results: Both of the treatments were effective in improving avoidant (P = 0.0001) and ambivalent (P = 0.0001) attachment styles, mentalization (P = 0.0001), and social cognition (P = 0.0001). These changes persisted from post-test to follow-up in mentalization (P = 0.003) and social cognition (P = 0.02). Conclusions: Although both methods are effective in improving the symptoms of the disorder, MBT is more effective in improving the basic structures of the BPD. This may lead to greater stability in the treatment.
Infusion-Related, Short-term, and Delayed Side Effects of Rituximab in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder
Authors: Farzadfard Farzane , Poursadeghfard Maryam , Ashjazadeh Nahid
Published: November 2020

Background: Rituximab is a monoclonal antibody against CD20 antigen present on mature B lymphocytes. It is commonly used in some hematologic, rheumatologic as well as neurologic disorders, including multiple sclerosis (MS) and neuromyelitis optica (NMO). Although there are some data about the safety of rituximab in patients with MS and NMO, there are few experiences regarding its safety in the Iranian population with MS, and known complications are often related to the studies conducted on the patients in other countries or with other autoimmune diseases and malignancies that are different from the population of patients with MS in terms of the underlying disease status and the concomitant medications or previous medications used. Objectives: The aim of this study was to investigate the infusion related, short-term and delayed side effects of rituximab on patients with MS and NMO in the population of the south of Iran. Methods: This was a longitudinal study on patients with MS and neuromyelitis optica who were referred to the health centers affiliated to Shiraz University of Medical Sciences from September 2018 to February 2019 and received Rituximab. They were observed for side effects from the first infusion of the drug to at least 6 months later. A checklist prepared by the researcher was used to collect the data. Independent t-test and chi-square test were used for data analysis. The significance level was considered 0.05 in this study. Results: In this study, 37% of the patients had at least one side effect during the first infusion. The most common side effect was chills (shivering). Short-term side effects occurred in 15.5% of the patients. The most common type was skin manifestations. These side effects led to hospitalization in two patients. Delayed side effect was developed in 20.7% of the patients. The most common delayed side effect was skin manifestations. Conclusions: Overall, there was no unexpected side effect in patients under the study and the side effects developed were comparable to previous studies as well as those conducted on patients other than patients with MS and neuromyelitis optica. Side effects were often mild, with only two cases leading to hospitalization, both of which were self-limiting as well, and there were no serious life-threatening side effects, except for one case with bradycardia.
Imagining a Philosophy of Warnings for Our Greatest Emergency
Authors: Zabala Santiago ,   DePaul University
Published: November 2020

In order to understand the essence of COVID-19 pandemic, it is necessary to take a step back and question the hierarchy of emergency in relation to other emergencies that are not addressed. This will also allow us to imagine a “philosophy of warnings” capable to interpret absent emergencies.
The structural changes of the Serbian merchandise trade during transition process: Comparative analysis of main trade indicators
Authors: Nikolić Goran , Nikolić Ivan
Published: November 2020

The article discussesthe structural changes in exports and imports during the transition process in Serbia. To address this issue, we calculated several indicators of the Serbian merchandise trade in the 2000-2018 period. After having computed the absolute growth of export and import and the values of intra-industry trade indices in the period under review, we compared the similarity of the export structure of Serbia and the import structure of the EU, which was used as a referent structure. To detect possible quality improvement of the Serbian trade sector, we analyzed qualitative changes of Serbia's exports (imports), through tendencies of goods at higher levels of processing, using more classifications, as such possible improvement would create important conditions for a sustainable and stronger export growth. After the calculation of trade specialization indicators, all obtained results were compared with those achieved by other Central and Eastern European (CEE) economies. The conclusion is that, despite strong Serbian export growth from 2000 to 2018 and moderate structural improvements, there are no conclusive signs of sufficient convergence to the EU import demand structure or sufficient growth of the share of goods at higher levels of processing in Serbian exports to imply the significant structural improvement of Serbia's trade, compared with CEE countries.
Modern imperatives of system-innovative approach to the solution of organizational and management tasks of digitalization of business processes
Authors: Somina Irina , Doroshenko Yury , Nikulina Olga
Published: November 2020

This article substantiates the feasibility of applying systematic, integrated, factorial and process approaches to solving relevant organizational and managerial tasks of digitalization aimed at improving the efficiency of innovation and the competitiveness of economic systems. Substantial foundations of the implementation of a systems approach in the field of digital transformation of business processes were revealed. The advantages of digitalization were presented, possible basic problems associated with its implementation were systematized, and factors that have a significant impact on their solutions were analyzed. It is obvious that the exciting new possibilities of digital technologies are open to the world community and the urgent need for their large-scale implementation manifested itself, but taking into account the optimal combination of various factors that have a significant impact on the development of socio-economic systems.
Analysis of factors that influence the employment of mothers with small children in Hungary
Authors: Kőmüves Zsolt , Petrás Viktória , Vig Salma
Published: November 2020

For women with young children, work and parenting are not mutually exclusive, but both are key. Together, the two help them live a full life. At the same time, they can still face a lot of job disadvantages, and those who manage to reconcile the two may have a privileged background. Based on the literature and its further reflection, we list the factors hindering the employment chances of women with small children.
Fernanda Beigel (ed.): The Politics of Academic Autonomy in Latin America
Authors: Hanafi Sari
Published: November 2020

Book Review of:

Fernanda Beigel (ed.) The Politics of Academic Autonomy in Latin AmericaFarnham: Ashgate 2013Hardcover, 290 pp.ISBN 9781409431862Price: € 120
Towards the Expert Governance: Social Scientific Expertise and the Socialist State in Czechoslovakia, 1950s–1980s
Authors: Sommer Vítězslav
Published: November 2020

This article is concerned with the process of introduction and the further expansion of social scientific expertise in state socialist Czechoslovakia from the mid-1950s until 1989. It presents these developments in the context of the changing policy strategies of the Communist Party elites and describes how closely social scientific expertise, and social scientific knowledge production in general, was interconnected with the broader development of the state socialist governance from the post-Stalinism of the second half of the 1950s to the 1980s perestroika period. This text is structured around three crucial realms of the state socialist governance: state, economy and labor, and socialist society. The first part of the article is concerned with the expertise in the field of state, law and political sciences, which played a significant role during the late 1950s, when the socialist statebuilding project was finished. The following section focuses on the rise of social scientific expert culture during the reform communist period of the 1960s. The third part of this study analyzes how the reform communist expert culture was transformed by the post-1968 regime in a large expert apparatus in order to build strictly centralized technocratic governance. Finally, this article describes how social scientific expertise responded to the crisis and disorganization of state socialist governance during the perestroika period.
Wisselgren: Social Science in Sweden
Authors: Turner Stephen
Published: November 2020

Book Review of:

Per Wisselgren, The Social Scientific Gaze: The Social Question and the Rise of Academic Social Science in SwedenSurrey, UK: Ashgate Publishing, 2015ISBN: 9781472447593Price: $121,20
L’economia col·laborativa com a palanca de progrés i sostenibilitat en temps de pandèmia
Authors: Torrent-Sellens Joan
Published: November 2020

Segurament, una de les principals lliçons de les crisis sanitària, econòmica, social i institucional vinculades, però no sempre del tot originades, amb la pandèmia de la COVID-19 (alguns investigadors ho anomenen sindèmies, o sigui pandèmies diferents però amb efectes comuns) és que no hi ha recuperació possible sense aprofundir en el procés de transformació digital i sense reorganitzar l’activitat econòmica per fer-la més sostenible.
Collaborative consumption, a buzzword that has gone conceptual: Three shades of the sharing economy
Authors: Ertz Myriam
Published: November 2020

It has been a decade now that research on the collaborative economy and colla- borative consumption (CC) has thrived. Tremendous academic research has been conducted into this specific concept. This paper re-evaluates the conceptual framework proposed almost half a decade ago about the conceptual foundations, frontiers and limits of the concept of collaborative consumption. The paper provides a revised definition and assesses to what extent the scope and limits in contrast to other forms of exchange still hold now despite current challenges.
Empleo y condiciones de trabajo en las plataformas de microtareas
Authors: Malo Miguel Ángel , Sánchez Santos Javier
Published: November 2020

En este trabajo se ofrece un breve panorama del empleo en las plataformas digitales de microtareas. Las principales cuestiones revisadas son: la lógica económica de estas plataformas; la cuantificación de este tipo de empleo; y el perfil de estos trabajadores y sus condiciones de trabajo. Se finaliza con una breve reflexión sobre los desafíos sociales que plantea este nuevo tipo de empleo.
THE DYNAMIC TRANSMITTING PROPERTIES OF A PIEZO-ELECTRIC PRESSURE BAR TRANSDUCER
Authors: FAN LIANG-ZAO  , XING WEI-FU  , JIN RUO-BING  ,   中国科学院北京力学研究所
Published: November 2020

The measuring time permitted for a pressure bar transducer is usually limited by the length of the pressure bar itself. To overcome this, we have studied the dyna-mic transmitting behavior of the pressure bar. Our results show that to obtain the correct pressure profile, one must reduce both the radial vibration in the neigh-borhod of the top end of the pressure bar, and the interference of reflected waves from the lower end with the incident wave. This paper presents a design for a pres-sure bar based on the principle of wave velocity dispersion, by which the perfor-mance of the transducer is greatly improved. The chief merit of the present design is that the permitted measuring time is no Longer limited by the length of the pres-sure bar.
12C(7Li. t) 16O AND 20Ne (d.6Li) 16O REACTIONS
Authors: SHI BING  ,   中国科学院高能物理研究所
Published: November 2020

This paper extends the Goldfarb-Buttle method which is used to treat the single particle transfer reactions induced by heavy ions to multi-particle transfer reactions. The 12C(7Li, t)16O and 20Ne(d, 6Li)16O reactions are calculated by using the coherent wave function for 16O, with due consideration to certain recoil effects. The results are compared with those obtained by experiment.
THE EQUIVALENT PHASE CENTER OF ANTENNA ON A PLANE GROUND
Authors: ZHANG JIN-BIAO
Published: November 2020

An approximate solution for the equivalent phase center of antenna on a plane ground and several related results have been given in this paper.
A USEFUL METHOD FOR INDEXING ELECTRON DIFFRACTION PATTERNS
Authors: LI CHUN-ZHI
Published: November 2020

In this paper, general expressions for coordinate transformation in crystal direct space or reciprocal space are derived by using of matrix calculus. A matrix method for indexing complex electron diffraction patterns of two phase structures, twins and high order Laue zones is described.
THEORY OF THE SUPERCONDUCTING CRITICAL TEMPERATURE (Ⅲ)
Authors: CAI JUN-DAO  , JI GUANG-DA  , WU HANG-SHENG  , CAI JIAN-HUA  , GONG CHANG-DE  ,   (1)南京大学; (2)中国科学技术大学; (3)中国科学院物理研究所
Published: November 2020

We have determined the first several coefficients of the series formula (1) for superconducting Tc. For the double-σ spectrum as α2F(ω)=λω/2[a1δ(ω-ω1)+(1-a1)δ(ω-ω2)] and that of several real materials, we have compared the Tc calculated from the series formula, the Allen-Dynes formula and the numerical solution of the Eliashberg Equation, respectively. The results suggest that when the series is convergent, the calculated results by using the series formula is a better approximation of the numerrieal solution than that from the A-D formula.We have also given an approximate Tc series formula, obtained a method to estimate the convergent radius of the Tc series and calculated the convergent radius for several materials. Therefore we may estimate the region in which the series formula (1) is valid.
THE EFFECT OF ALLOY ELEMENTS ON THE Nb3Sn GROWTH KINETICS
Authors: METAL INTERFACE RESEARCH GROUP  , PEKING UNIVERSITY DIVISION No.7  ,   (1)宝鸡有色金属研究所; (2)北京大学物理系
Published: November 2020

The effect of alloy element Zr on the Nb3Sn growth kinetics at the Cu-Sn/Nb interface has been investigated. Experiments have revealed that the addition of Zr in single core composites increases the growth rate substantially and the variation of the Nb3Sn layer thickness with reaction time obviously exceeds the parabolic law. These results cannot be interpreted fully taking into account the fineness of Nb3Sn grains caused by the ZrO2 particles formed during heat treatment, and it is necessary to consider the increase of diffusion coefficient caused by supersaturation of vaeances around the ZrO2 particles. The depletion of Sn contents in the Cu-Sn matrix of multifilamentary composites during heat treatment greatly influenced the growth rate. The revised formula of growth kinetics gives a satisfactory explanation on the experimental results.
THE CRYSTAL STRUCTURE OF MnGa AND THE DEGREE OF ORDER
Authors: LU XUE-SHAN  , LIANG JING-KUI  , YANG ZHONG-RUO  ,   中国科学院物理研究所
Published: November 2020

The crystal structure of the γ3 phase in the Mn-Ga system has been determined by the Debye-Scherrer method, and thence the degree of order in the atomic arrangement in this phase region has been estimated as a function of the gallium content.The structure of the γ3 phase belongs to the tetragonal system, the space group being D4h1-P4/mmm. The ideal stoichiometric composition is MnGa, and each unit cell contains one formula weight, the manganese and gallium atom occupying (000) and 1/2 1/2 1/2) positions respectively. It is a distorted form of the B structure, and if it is rotated π/4 about the c-axis, the transformed unit cell can be shown to be of the type LI0, isomorphous with CuAu-I. At room temperature, the lattice spaeings of the original cell at 42.9 at.% Ga are α=2.7475? and c=3.6756?.This phase may be considered as a substitutional solid solution of γ-Mn, stabilized at room temperature due to the partial substitution of manganese atoms by gallium atoms as a tetragonal face-centred ordered structure. In this entire phase region, the degree of order increases with the gallium content.
INVESTIGATION OF THE PSEUDO-TERNARY SYSTEM SrNb2O6-NaNbO3-LiNbO3
Authors: TANG DI-SHENG  , LIANG JING-KUI  , SHI TING-JUN  , ZHANG YU-LING  , TIAN JING-HUA  , LI WEN-XIU  ,   中国科学院物理研究所
Published: November 2020

The pseudo-ternary system SrNb2O6-NaNbO3-LiNbO2 has been investigated by means of DTA, heat treatment and X-ray diffraction techniques. It has been found that at room temperature Sr2Na(NbO3)5(S2N) is a metastable intermediate compound which has a tetragonal tungsten-bronze structure with a=12.36?, c=3.906?. LiNbO3 can be dissolved in S2N up to a limit about 10 mol% ; and in the range of 5-10mol% of LiNbO3, the S2N phase is distorted into S2N′, which belongs to the orthorhombic system and is also a metastable phase. After long time annealing at 900-1100℃, the metastable phases S2N, S2N′ will decompose into a mixture of SrNb2O6 and a phase of solid solution based on NaNbO3. The phase diagram of the corresponding binary systems and the isothermal section of the pseudo-ternary system have been established.
INVESTIGATION OF THE STRUCTURE AND THE PROCESS OF PHASE TRANSFORMATION ABOUT δ-FeOOH
Authors: DU YOU-WEI  , ZHANG YU-CHANG  , JIAO HONG-ZHEN  , LU HUAI-XIAN  , LI ZHENG-YU  , GU BEN-XI  ,   南京大学物理系
Published: November 2020

The structure of δ-FeOOH and the process of the phase transformation were studied by means, of thermogravimetric plots, differential thermal analysis, magnetic analysis, X-ray Diffraction and Mossbauer effect measurement.
THE TRANSDUCER BANDWIDTH OF ACOUSTO-OPTIC DEVICES AND THE DETERMINATION OF THE LAYERS' THICKNESS
Authors: XU JIE-PING  ,   北京工业大学
Published: November 2020

According to the Mason's equivalent circuit of piezoelectric transducer, we have calculated the functional relationship between transducer loss TL and normalized frequency f/f0 for the 36°y-cut LN/PM and the x-cut LN/TeO2 acousto-optic devices, with different layer materials and thickness. From these calculations, we can determine the thickness of the various layers rationally and the transducer bandwidth of the devices accurately. We give also the loci of the electric input- impedence Zi with f/f0 on the Smith chart, which can be used as theoretical foundation of quality tests for the devices.
A STUDY OF PROTON IMPLANTATION FOR GaAs
Authors: WANG WEI-YUAN  , XU JING-YANG  , NI QI-MIN  , TAN RU-HUAN  , LIU YUE-QIN  , QIU YUE-YING  ,   中国科学院上海冶金研究所
Published: November 2020

In this paper, a study has been made of proton implantation and annealing behavior of GaAs. The single crystal wafers used in the implantation were oriented typically at 1-3° away from (100), and doped with Sn to 5×1017-1×1018cm-3. The implantation was carried out at room temperature in a proton accelerator and ion implantation machine with an energy of 8×104-2×106eV. Following bombardment, the implanted area was delineated by means of an A-B etchant, and the penetration depth of proton xj was determined. The xj values obtained can be related to the implantation energy E as follows xj= (8.716×10-4+4E-1)E1.365,where Xj is in ?, E in eV. The maximum lateral spread of the proton XL as a function of energy was also, determined, and found to be ～104? when E>3×105eV. The proton implanted samples were annealed at 150-800℃ for 5 min. A X-ray double crystal difractrometer was used to characterize the recovery of strain, and a electrometer was used to determine the resistance variation with annealing temperature. The results showed that the critical dose φ* for amorphous layer formation after proton implantation was ～1016cm-2, and the recovery of strain began at 150°, and virtually stopped at 450°. In the temperature range 150-450°, there were no significant variation in implanted resistance. The recovery of resistance oecurred only at higher temperatures. The project range of proton Rp, the electron stopping power Se(E), the nuclear stopping power Sn(E), and the mechanism of annealing of implanted proton in GaAs are discussed on the basis of the present experimental results.
THEORETICAL INTERPRETATION OF THE ENHANCEMENT OF NEUTRON DIFFRACTION IN AN α-LiIO3 SINGLE CRYSTAL UNDER THE ACTION OF A DC FIELD
Authors: XU ZHENG-YI  , LI TIE-CHENG  , GU BEN-YUAN  ,   中国科学院物理研究所
Published: November 2020

We have noticed in α-LiIO3 single crystals the following experimental facts: (1) Using the conoscopic observation method, it was found the contrast of layer imperfections increasing with the strength of a dc field. (2) Changes take place in the x-ray topography under the action of a dc field. (3) The grown-in spatial variation of lattice parameters were found and measured by an x-ray double-crystal spectrometer. Based on these observations, we infer that space charges (carriers, impurity ions and vacancies) are accumulated at the defects of macroscopic scale, which in turn produces a gradient of lattice parameters under the action of a dc field. We calculated the neutron Bragg scattering cross section for a distorted single crystal using the Born approximation and taking into account the extinction at the same time. Therefrom, the enhancement of diffraction in an α-LiIO3 crystal under the action of a dc field were qualitatively interpreted with good agreement.
BANDS OF SCATTERED LIGHT PRODUCED IN AN α- LiIO3 SINGLE CRYSTAL UNDER THE ACTION OF A DC ELECTRIC FIELD
Authors: YANG HUA-GUANG  ,   中国科学院物理研究所
Published: November 2020

When a laser beam passes through an α-LilO3 single crystal under the action of a DC electric field along the c-axis, it is found that bands of scattered light are produced. The bands are perpendicular to the c-axis and subtend large, angles with the crystal as vertex. The distribution of intensity of the band is not symmetric with respect to the transmitted light spot. When the electric vector of incident beam is perpendicular to the c-axis, then that of scattered beam would be parallel to the c-axis; and when the former is parallel to the c-axis, then the latter would be perpendicular to the c-axis. If the former is neither perpendicular nor parallel to the c-axis then two bands would appear, the electric vectors of which are parallel and perpendicular to the c-axis respectively. Under specific condition, these bands coincide. The polarization, intensity and relaxation behaviour of these bands have been studied in detail. We believe that these bands result very likely from some effect of carriers moving along the c-axis in the crystal. In addition we have observed the defects in the crystal under the action of a DC electric field with optical microscope.
A NEW METHOD FOR SOLVING THE FREE-BOUNDARG MAGNETIC SURFACE EQUATION WITHOUT CONDUCTING SHELLS
Authors: SHEN JIE-WU  , ZHOU YU-MEI  , QING CHENG-RUI  ,   (1)中国科学院理论物理研究所; (2)中国科学院物理研究所
Published: November 2020

The iteration method for solving the free-boundary magnetic surface equation with conducting shells has been generalized to the case of infinite region with external currents and without conducting shells. In order to do this a coordinate transformation of the form x′=x/(1+x) is carried out which enables to get a sufficient accuracy inthe region of plasmas while the meshes in the region of vacuum would not be increased. After restricting the radial region of the plasma currents the iteraction series described in [1] can be used to find the equilibrium solution of magnetic surface equation. The numerical solution of this equation in one dimension is obtained and compared with the result obtained analytically. The method described above can effectively be used in cases of two-dimension without difficulties.
RENORMALIZED QUASI-LINEAR THEORY OF TURBULENCE IN NON-UNIFORM PLASMA (Ⅰ)——GENERALIZATION OF MISQUICH-BALESCU THEORY
Authors: QIU XIAO-MING  ,   中国西南物理研究所
Published: November 2020

In deriving the diffusion equation, diffusion tensor and dispersion relation in respect of the inhomogeneity in plasma, the Misquich-Balescu's theory on turbulence in uniform plasma can be generalized to the case of non-uniform plasma. It is indicated that the method given by Pelletier et al. in considering the plasma turbulence as a Markov process is now inadequate to describe the turbulence in non-uniform Plasma.
RENORMALIZED QUASI LINEAR THEORY OF TURBULENCE IN NON UNIFORM PLASMA (Ⅱ)——RESONANT DIFFUSION IN A TURBULENT PLASMA
Authors: QIU XIAO-MING  ,   中国西南物理研究所
Published: November 2020

Upon the basis of the theory in article I, we have derived an explicit expression of resonant diffusion tensor in terms of the steady-state turbulent spectrum Sk0(0) and compared our result with that given by Birmingham et al. We also compare the dispersion relation derived in I with the corresponding result derived by Birmingham et al.
THE CALCULATION OF CURRENT OF MAINTAINING FIELD IN TOROIDAL PLASMA EQUILIBRIUM
Authors: ZHANG CHUN-YUAN  , SUN JI-GUANG  , QING CHENG-RUI  ,   (1)中国科学院计算中心; (2)中国科学院物理研究所
Published: November 2020

In this paper a method is presented for solving the equilibrium problem with axisymmetry for arbitraryly given plasma configurations. First, the boundary value problem of equilibrium equation is solved by finite element method for a given plasma boundary and current distribution. Then, based on virtual-casing principle, the virtual-casing current which produces the maintaining magnetic field requisite for the equilibrium is obtained by using solution of the equilibrium equation. The field of virtual-casing current, i.e. the maintaining field inside plasma is calculated. The current distribution of maintaining field on a certain contour outside the plasma is found by means of solving the integral equation. The main difficulty confronted in solving the integral equation problem is that one has to deal with an incorrectly posed problem. We have solved the incorrectly posed Fredholm integral equation of first kind, using a method of singular value decomposition. This method is simple and effective in solving such an equilibrium problem.We have considered seven types of plasma configuration including circular, elliptic, doublet, race-track, D-, back D- and banana shapes and three kinds of plasma current distribution including quasi-uniform, diffusion-type and skin-type distribution. Three type of current distribution for maintaining field are obtained in a given circular-, elliptic- and -shapes. For the models as mentioned above, the current distribution of maintaining field and the field itself are given. The total currents of maintaining field and total plasma currents are compared with each other. Some influences of the maintaining fields on stability is discussed.
MOVEMENT OF SPACE SPECKLE
Authors: WU XIAO-PING  , HE SHI-PING  , LI ZHI-CHAO  ,   中国科学技术大学
Published: November 2020

The diffusing reflective surface illuminated by coherent light generates random speckle in space. The movement of the surface relative to the source causes corresponding movement of the speckle. When a moving speckle is tracked, it implies that the intensity of speckle is constant yet the phase of the speckle is allowed to vary. From the Fresnel-Kirchhoff Integration, three fundamental rules of speckle movement are derived, i.e. Equations (3), (4) and (5) in this paper. The first and second equations are similar to those of grating. The third equation is similar to the lens law. From these rules, a speckle movement formula, relating to the surface movement, is derived as equation (18), in which the coordinate system adopted is fixed in space. It is an equation in matrix form, which denotes six types of surface movements, i. e. three rotations and three translations. The experimental results are in good agreement with this formula. These fundamental rules can be used to analyse general space diffractive patterns.
THE ABSORPTION SPECTRUM AND QUANTUM STATES OF NEODYMIUM ION (Nd3+) IN SINGLE CRYSTAL OF ANHYDROUS NEODYMIUM CHLORIDE AND ANHYDROUS PRASEDYMIUM CHLORIDE
Authors: SONG ZENG-FU  , ZHANG HE-YI  , XU YAO-ZHOU  , LUO ZHEN-JI  , JIAN HONG-ZHONG  , XI DE-FA  , WANG TAI-FU  , LIANG MIN-JI
Published: November 2020

The absorption spectra of Nd3+ in pure anhydrous neodymium chloride crystals and in anhydrous praseodymium chloride crystals (containing 0.1% NdCl3) have been examined systematically examined. The structures of the groups of their absorption lines are found to be similar to those of Nd3+ in NdCl3 crystals diluted by LaCl3 (containing 2% NaCl3 in LaCl3), except for a shift of the spectrum towards the long wave side. The shifts (relative to the ground state) of these corresponding sub-levels are proportional to the length of unit cell of the single crystals.
COLOR RESTORATION OF FADED COLOR FILMS WITH WHITE-LIGHT PROCESSING
Authors: Francis. T. S. YU  , G. G. MU
Published: November 2020

A technique of color restoration for faded color films with whitelight optical processing is presented. The color restoration can be accomplished with spatial encoding and color filtering. Although the technique offers an advantage of faded color encoding, however, it is not a real-time technique. We have also presented a real-time color restoration with white-light optical processing technique. Experimental demonstrations of this color restoration technique are also included. We have shown that the white-light color restoration is a simple, versatile and economical technique. The white-light processing technique also offers the advantage of direct viewing capability, which is very suitable for instantaneous color restoration and enhancement applications.
ALUMINIUM CHEMISORPTION ON THE SEMICONDUCTOR SURFACES
Authors: ZHANG KAI-MING  , YE LING  , XU YONG-NIAN  ,   复旦大学现代物理研究所
Published: November 2020

The cluster model and the self-consistent extended Huckel method are used to calculate the stable configuration for the chemisorption of Al on both the Si(lll) and GaAs(110) surfaces. The calculated results show that the threefold ionic chemisorption for Al/Si (111) is more stable than that for the covalent top site, and the LDOS for the threefold site agrees quite well with the experimental data. In the case of Al/GaAs(110), the Al adatom substitutes the surface Ga atom to form an AlAs layer, and the Al chemisorption leads the relaxed GaAs (110) back to the unrelaxed ideal position.
LOW FREQUENCY DIELECTRIC PROPERTIES OF PZT-8 FERROELECTRIC PIEZOELECTRIC CERAMICS
Authors: ZHANG WEI-PIN  , LI CHONG-ZHOU  ,   中国科学院物理研究所
Published: November 2020

This article presents results of our studies on PZT-8 polycrystalline ferroelectric ceramics of lead zirconate titanate. We have measured the dielectric constant and dielectric loss over a low frequency range (from . 100kHz-20MHz) and temperature range from room temperature to 500℃. The mechanism of dielectric loss, the relaxation process and the impurity effects are discussed. The main loss above Tc is attributed to conducting loss.We also propose some suggestions for improving electrical properties of PZT-8 ferroelectric ceramics.
ANALYSIS OF THE SPECIAL STRUCTURES OF DISLOCATIONS IN HCP METALS
Authors: LI ZONG-QUAN  , ZHANG LI-DE  , LONG QI-YI  , HE YI-ZHEN  , LI YONG-HONG  , TIAN FENG-ZUO  ,   (1)冶金工业部有色金属研究总院; (2)中国科学院金属研究所
Published: November 2020

In this paper, we discuss the special structures of dislocations in h.c.p. metals. Two sets of dislocations that lay on two parallel non-basal slip planes will change their shape soasto become zigzag and form regular dislocation structures if the spacing of the slip planes is smaller than one quarter of the distance between the dislocations in the dislocation array. Under TEM observation, these structures appear to be regular dislocation networks that present double lines in one direction. Two of these dislocation networks in α-Ti were observed and others were shoAved schematically.
AN ALTERNATIVE DERIVATION OF COHERENT-POTENTIAL APPROXIMATION FOR DISORDERED ALLOYS-TIGHT BINDING MODEL
Authors: ZHANG ZHAO-QING  ,   中国科学院物理研究所
Published: November 2020

The coherent-potential approximation (CPA) for both single-particle and two-particle Green's functions are rederived using locator expansion method proposed by Matsubara and Toyozawa. Instead of using self-contained cumulant expansion to treat the excluded volume effects for atoms, we use a diagrammatic method with the idea first proposed by Yonezawa. A systemmatic method is used to generate self-consistent equations for all single-site diagrams. We emphasis our treatment for two-particle Green's function which can be extended to obtain the corresponding CPA equation for electrical conductivity in liquid metals and amorphous solids.
SIMULTANEOUS MEASUREMENT OF THE CONSTITUENT AND THICKNESS OF THIN FILM BY X-RAY EDS
Authors: CHENG WAN-BONG  , GAO QIAO-JUN  , WU ZI-QIN  ,   北京大学物理系
Published: November 2020

A new method which can simultaneously determine the constituent and thickness of the alloy films using the X-ray EDS has been developed. The constituent is determined by the ratios of the kα intensties of elements in the film. The thickness of the film deposited on a NaCl substrate is measured by the attenuation of the ratios of Na kα intensity/Cl kα intensity. It is not necessary to use bulk standards of pure elements. This method has been applied to Cu-Si alloy films of different thickness deposited on NaCl substrate. Under various experimental conditions, the constituent and thickness data are determined satisfactorily.
CALCULATION OF ELASTIC CONSTANTS OF SIMPLE METALS BY PSEUDOPOTENTIAL METHOD
Authors: LI SHU-SHAN  , LIN GUANG-HAI  ,   中国科学院力学研究所
Published: November 2020

The second and third order elastic constants of seven simple metals (Li, Na, K, Eb, Cs, Al and Pb) are calculated using the one-parameter Heine-Abarenkov model potential with the Hubbard-Sham dielectric function. The two adjustable parameters are determined from the experimental data of the elastic constant C44 and the lattice constant of the crystal at 0 K and zero pressure. The calculated results are in comparatively good agreement with the experiments or the theoretical calculations of other authors. Especially for Al, the present results of the third order elastic constants are closer to the experimental data than those found in the literatures.
DISLOCATIONS AND INCLUSIONS IN CZOCHRALSKI METHOD-GROWN YAG SINGLE CRYSTALS
Authors: GE CHUAN-ZHEN  , XU XIU-YING  , FENG DUAN  ,   南京大学固体物理研究所
Published: November 2020

The relationship between the dislocations, the inclusions and the growth striations in YAG single crystals were studied with birefringence topography. The experimental evidence shows that the inclusions are adsorped preferentially at the outcrops of dislocations at the solid-liquid interface and the relative sizes of the inelusions correspond to the heights of growth-steps which are related to the normal components of Burgers vectors of dislocations.
THE CRYSTAL STRUCTURE AND ABSOLUTE CONFIGURATION OF QUININE SALT OF (+)-O-ETHYL O-PHENYL PHOSPHOROTHIOIC ACID
Authors: DOU SHI-QI  , ZHENG QI-TAI  , DAI JIN-BI  , TANG CHU-CHI  , WU GUI-PING  ,   (1)南开大学元素有机化学研究所; (2)中国科学院生物物理研究所
Published: November 2020

The crystal of Quinine salt of (+)-0-ethyl O-phenyl phosphorothioic acid belongs to orthorhombic system with space group D24-P21 21 21 and cell parameters a= 29.007 (7)?, b = 14.089 (4)?, c = 6.589 (3)?. There are four molecules ia each unit coll, Z= 4. X-Ray diffraction intensity data are collected on PW-1100 four-circle diffracto-meter, using CuKα radiation. The number of independent diffraction data amounts to 2818, and 2463 are observable reflections. The crystal structure has been determined by direct method (MULTAN-78). The structure parameters were refined by full-matrix least-square method to R=0.082. The absolute configuration has been assigned by direct measurement of 18 enantioner-sensitive Bijvoet reflection pairs. The properties of P-O, P-S bond types were discussed.
ELECTRON MICROSCOPY OF HUANGHOITE
Authors: LI FANG-HUA  , FAN HAN-JIE  , YANG DA-YU  , FU PING-QIU  , KONG YOU-HUA  ,   (1)中国科学院地球化学研究所; (2)中国科学院物理研究所
Published: November 2020

Huanghoite fBaGe(CO3)F] is a new mineral discovered in China. The parameters of the hexagonal unit cell have been determined as α=5.07?, c=38.6? by using electron diffraction method. The value of c is twice as large as that determined previously by X-ray diffraction analysis. Huanghoite is composed of atoms with large difference in atomic number. The advantage of electron diffraction in investigating such kind of minerals is discussed.The stacking faults along direction c have been observed by lattice imaging technique. The possille cause of formation of such faults is proposed.
THE COHERENCE OF RADIATION AND INCREASE IN ENTROPY
Authors: NI GUANG-JIONG  , CHEN SU-QING  , ZHOU GU-SHENG  ,   复旦大学物理系
Published: November 2020

A model of radiation by multi-atoms is discussed. System A, composed of N atoms with two energy levels, is coupled with a single-mode radiation B. A and B are in turn coupled with two thermal reservoirs D and C respectively, and we also assume that all atoms which are located within a wave length of the radiation field have the same phase. Then under the approximation of long wave, rotating wave and mean fields, by introducing Markov approximation after using the method of density matrix, we have derived the of equations motion for systems A and B respectively. These equations are concerning with the following processes: the spontaneous emission of single atom, the absorption and induced emission stimulated by thermal radiation, the induced emission of N atoms stimulated by single mode coherent state radiation as well as the coherent spontaneous emission of this multi-atoms system. The latter two processes are actually the two kinds of superradiance originated from Dicke model and had been investigated previonsly. We have analysed these five processes by numerical calculations. Besides, the influence of these processes upon the evolution of atomic system attaining thermal equilibrium and the increase of entropy is also discussed. It is pointed out that the correlations inside a multi-atoms system would not be destroyed by coherent spontaneous emission, in contrast with the incoherent one which leads to the change of entropy in atomic system. However, only when the entropy of the two reservoirs has been taken into account, will it be possible to demonstrate the mono-tonic increase in total entropy.