The Bubble Behaviour under Effect of Centrifugal Force

2008 ◽  
Vol 39-40 ◽  
pp. 475-480 ◽  
Author(s):  
Vladislava Tonarová ◽  
Lubomír Nĕmec
Keyword(s):  
Centrifugal Force ◽  
Initial Composition ◽  
Centrifugal Field ◽  
Positive Role ◽  
Bubble Separation ◽  
Partial Filling ◽  
Set Up ◽  
Small Bubbles ◽  
Bubble Behaviour

The fining process may be enhanced by acting of additive force on bubbles in the glass melt. This study deals with behaviour of single bubbles under effect of centrifugal force in a rotating discontinuous cylinder with glass melt. The model of a single bubble in the combined gravitational and centrifugal field has been set up and calculations of bubble behaviour in the cylinder have been performed for the model TV glass. Two mechanisms of bubble separation were indicated from results of calculations, i.e. the complete dissolution and separation by centrifugal force. The first mechanism is restricted to areas close to cylinder mantel and exhibits relatively long bubble dissolution times. The analysis of model and results revealed the potentially positive role of increasing cylinder radius and partial filling of rotating cylinder with glass melt. The bubble separation is considerably influenced by bubble dissolution or growth during centrifuging, thus the crucial role in this process plays temperature and the bubble initial composition. The until now results show that at lower temperatures the bubbles should contain low content of gases well soluble in glass, to admit higher rotation velocities. Whereas to be enabled the transport of chemically soluble gases from the melt into the bubbles at high temperatures, the bubbles have to be treated at lower rotation velocities (ω =25 – 50 s-1). The small bubbles tend to dissolve close to the cylinder mantle, but from other cylinder regions they have to be separated by centrifuging, and this is a very slow process. Some pretreatments of the glass melt is considered to get rid of bubbles having size under 0.1 mm.

MODERNIZATION OF ENGINEERING EDUCATION IN A REGIONAL UNIVERSITY IN THE CONDITIONS OF ITS ESTABLISHMENT AS A UNIVERSITY CENTER FOR INNOVATIVE, TECHNOLOGICAL AND SOCIAL DEVELOPMENT OF THE REGION: CHALLENGES AND OPPORTUNITIES

2020 ◽  
Vol 5 (98) ◽  
pp. 136-152
Author(s):  
SVETLANA V. EGORENKOVA ◽  
VLADIMIR V. ERMILOV ◽  
ALEKSANDR O. KOCHNEV
Keyword(s):  
Engineering Education ◽  
Software Systems ◽  
State University ◽  
Positive Role ◽  
University Center ◽  
Regional University ◽  
Challenges And Opportunities ◽  
Set Up ◽  
Training Organization

The paper discusses the problems and challenges of engineering education, aspects of its modernization in the context of project training organization at universities that is based on the principles of CDIO, focused on generating innovation and addressing the specific needs of the regional economy. In the article, the authors cite and summarize the experience of software organization in four universities that have successfully implemented and used software: Astrakhan State University, Moscow Polytechnic University, National Research Tomsk Polytechnic University and Tomsk State University of Control Systems and Radioelectronics. Information on the implementation of software in ChSU is also used. By analyzing information, the authors draw conclusions relating to the positive role of project learning (introduced and practiced in universities) for the development of regions, the necessary measures to set up software systems at universities.

scholarly journals Networks, Proximities, and Interfirm Knowledge Exchanges

2015 ◽  
Vol 40 (4) ◽  
pp. 377-404 ◽  
Author(s):  
Stefano Usai ◽  
Emanuela Marrocu ◽  
Raffaele Paci
Keyword(s):  
Strategic Alliances ◽  
Preferential Attachment ◽  
Full Range ◽  
Economic Activities ◽  
Positive Role ◽  
Five Dimensions ◽  
Social Proximity ◽  
Relevant Effect ◽  
Set Up

Building on previous literature that provides extensive evidence concerning flows of knowledge generated by interfirm agreements, in this article, we aim to analyze how the occurrence of such collaborations is driven by multidimensional proximity among participants and by their position within firms’ networks. More specifically, we assess how the likelihood that two firms set up a partnership is influenced by their bilateral geographical, technological, organizational, institutional, and social proximity and by their position within networks. Our analysis is based on agreements in the form of joint ventures or strategic alliances, announced over the period 2005–2012, in which at least one partner is localized in Italy. We consider the full range of economic activities, which allows us to offer a general scenario and to investigate specifically the role of technological relatedness across different sectors. The econometric analysis, based on the logistic framework for rare events, provided three noteworthy results. First, all five dimensions of proximity jointly exert a positive and relevant effect in determining the probability of interfirm knowledge exchanges, signaling that they complement each other rather than function as alternative channels. Second, the highest impact on probability is due to technological proximity, followed by organizational, geographical, and institutional proximities, while social proximity has a limited effect. Third, we find evidence concerning the positive role played by networks, through preferential attachment effects, in enhancing the probability of interfirm agreements.

scholarly journals A REVIEW OF CLINICAL LEGAL EDUCATION’S (CLE) EXPERIENCE IN UNIVERSITI SAINS ISLAM MALAYSIA

2021 ◽  
Vol 9 (1) ◽  
pp. 35-46
Author(s):  
Norsuhaida Che Musa ◽  
Nor Fadzlina Nawi
Keyword(s):  
Teaching And Learning ◽  
Learning Strategy ◽  
Learning Experience ◽  
Legal Education ◽  
Pilot Project ◽  
Law Students ◽  
Written Feedback ◽  
Positive Role ◽  
Set Up

Various research has given valuable insights into the positive role of Clinical Legal Education (CLE). However, there is a dearth of empirical data reviewing the set-up of CLE in public law schools in Malaysia and assessing its role as a teaching and learning strategy in legal education. This paper summarises the development and structure of the Faculty of Syariah and Law's Legal Clinic pilot initiative at the Universiti Sains Islam Malaysia (USIM). It assesses the impacts of the initiative on students' learning experience. The assessment involved a content analysis of written feedback given by a batch of pioneer students selected to join the FSU Legal Clinics pilot project in 2019. The findings indicated that the students believe exposure to the legal clinic increases their comprehension of the law's application and provides awareness of the professional skills and values involved in the legal profession. The sample is small, and the findings are preliminary. However, it is hoped that the results will inform legal curriculum developers of the benefits that law students derived from their clinical experience and provide a basis for further research into formally including clinical legal education in the FSU legal curriculum. This paper also advocates that although setting up, planning and organising activities for a successful legal clinic involved a great deal of preparation, it would benefit students and be integral to teaching and learning strategy in legal education in FSU USIM.

Are Three Items Sufficient to Measure Sense of Coherence?

2018 ◽  
Vol 34 (4) ◽  
pp. 229-237 ◽  
Author(s):  
Francesca Chiesi ◽  
Andrea Bonacchi ◽  
Caterina Primi ◽  
Alessandro Toccafondi ◽  
Guido Miccinesi
Keyword(s):  
Sense Of Coherence ◽  
Convergent Validity ◽  
Clinical Sample ◽  
Clinical Samples ◽  
Depression Symptoms ◽  
Time Saving ◽  
Positive Role ◽  
Patients With Cancer ◽  
Measure Sense

Abstract. The present study aimed at evaluating if the three-item sense of coherence (SOC) scale developed by Lundberg and Nystrom Peck (1995) can be effectively used for research purpose in both nonclinical and clinical samples. To provide evidence that it represents adequately the measured construct we tested its validity in a nonclinical (N = 658) and clinical sample (N = 764 patients with cancer). Results obtained in the nonclinical sample attested a positive relation of SOC – as measured by the three-item SOC scale – with Antonovsky’s 13-item and 29-item SOC scales (convergent validity), and with dispositional optimism, sense of mastery, anxiety, and depression symptoms (concurrent validity). Results obtained in the clinical sample confirmed the criterion validity of the scale attesting the positive role of SOC – as measured by the three-item SOC scale – on the person’s capacity to respond to illness and treatment. The current study provides evidence that the three-item SOC scale is a valid, low-loading, and time-saving instrument for research purposes on large sample.

A reconnaissance of tropical resources during Revolutionary years: the role of the Paris Museum d'Histoire Naturelle

1991 ◽  
Vol 18 (3) ◽  
pp. 333-362 ◽  
Author(s):  
MADELEINE LY-TIO-FANE
Keyword(s):  
South Africa ◽  
Natural History ◽  
Scientific Research ◽  
Extensive Literature ◽  
War Of Independence ◽  
Leading Role ◽  
Scientific Principles ◽  
Set Up ◽  
Joseph Ii

SUMMARY The recent extensive literature on exploration and the resulting scientific advances has failed to highlight the contribution of Austrian enterprise to the study of natural history. The leading role of Joseph II among the neutral powers which assumed the carrying trade of the belligerents during the American War of Independence, furthered the development of collections for the Schönbrunn Park and Gardens which had been set up on scientific principles by his parents. On the conclusion of peace, Joseph entrusted to Professor Maerter a world-encompassing mission in the course of which the Chief Gardener Franz Boos and his assistant Georg Scholl travelled to South Africa to collect plants and animals. Boos pursued the mission to Isle de France and Bourbon (Mauritius and Reunion), conveyed by the then unknown Nicolas Baudin. He worked at the Jardin du Roi, Pamplemousses, with Nicolas Cere, or at Palma with Joseph Francois Charpentier de Cossigny. The linkage of Austrian and French horticultural expertise created a situation fraught with opportunities which were to lead Baudin to the forefront of exploration and scientific research as the century closed in the upheaval of the Revolutionary Wars.

Positive Role of Synthesis Method and Hard Template on the Catalytic Performance of SAPO-34 in Methanol to Olefin Reaction.

2020 ◽  
Vol 23 ◽  
Author(s):  
Sajjad Rimaz ◽  
Reza Katal
Keyword(s):  
Particle Size ◽  
Synthesis Method ◽  
Catalytic Performance ◽  
Hard Template ◽  
Structure Directing Agent ◽  
Positive Role ◽  
Methanol To Olefin ◽  
Dg Method ◽  
Synthesis Procedure

: In the present study, SAPO-34 particles were synthesized using hydrothermal (HT) and dry gel (DG) conversion methods in the presence of diethyl amine (DEA) as an organic structure directing agent (SDA). Carbon nanotubes (CNT) were used as hard template in the synthesis procedure to introduce transport pores into the structures of the synthesized samples. The synthesized samples were characterized with different methods to reveal effects of synthesis method and using hard template on their structure and catalytic performance in methanol to olefin reaction (MTO). DG conversion method results in smaller particle size in comparison with hydrothermal method, resulting in enhancing catalytic performance. On the other side, using CNT in the synthesis procedure with DG method results in more reduction in particle size and formation of hierarchical structure which drastically improves catalytic performance.

Effects of Myo-inositol Alone and in Combination with Seleno-Lmethionine on Cadmium-Induced Testicular Damage in Mice

2019 ◽  
Vol 12 (4) ◽  
pp. 311-323 ◽  
Author(s):  
Salvatore Benvenga ◽  
Antonio Micali ◽  
Giovanni Pallio ◽  
Roberto Vita ◽  
Consuelo Malta ◽  
...  
Keyword(s):  
Structural Changes ◽  
Natural Antioxidants ◽  
Minor Role ◽  
Positive Role ◽  
Testosterone Levels ◽  
Tnf Α ◽  
Testicular Lesions ◽  
A Minor ◽  
Immunohistochemical Analyses

Background: Cadmium (Cd) impairs gametogenesis and damages the blood-testis barrier. Objective: As the primary mechanism of Cd-induced damage is oxidative stress, the effects of two natural antioxidants, myo-inositol (MI) and seleno-L-methionine (Se), were evaluated in mice testes. Methods: Eighty-four male C57 BL/6J mice were divided into twelve groups: 0.9% NaCl (vehicle; 1 ml/kg/day i.p.); Se (0.2 mg/kg/day per os); Se (0.4 mg/kg/day per os); MI (360 mg/kg/day per os); MI plus Se (0.2 mg/kg/day); MI plus Se (0.4 mg/kg/day); CdCl2 (2 mg/kg/day i.p.) plus vehicle; CdCl2 plus MI; CdCl2 plus Se (0.2 mg/kg/day); CdCl2 plus Se (0.4 mg/kg/day); CdCl2 plus MI plus Se (0.2 mg/kg/day); and CdCl2 plus MI plus Se (0.4 mg/kg/day). After 14 days, testes were processed for biochemical, structural and immunohistochemical analyses. Results: CdCl2 increased iNOS and TNF-α expression and Malondialdehyde (MDA) levels, lowered glutathione (GSH) and testosterone, induced testicular lesions, and almost eliminated claudin-11 immunoreactivity. Se administration at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression, maintained GSH, MDA and testosterone levels, structural changes and low claudin-11 immunoreactivity. MI alone or associated with Se at 0.2 or 0.4 mg/kg significantly reduced iNOS and TNF-α expression and MDA levels, increased GSH and testosterone levels, ameliorated structural organization and increased claudin-11 patches number. Conclusion: We demonstrated a protective effect of MI, a minor role of Se and an evident positive role of the association between MI and Se on Cd-induced damages of the testis. MI alone or associated with Se might protect testes in subjects exposed to toxicants, at least to those with behavior similar to Cd.

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