Effects of Sub-Freezing Temperatures on Graphite/Epoxy Composite Materials

1989 ◽  
Vol 111 (4) ◽  
pp. 438-439 ◽  
Author(s):  
T. K. Tsotsis
Keyword(s):  
Composite Materials ◽  
Residual Stresses ◽  
Low Temperatures ◽  
Epoxy Composite ◽  
Ice Crystals ◽  
Cryogenic Temperatures ◽  
The Past ◽  
The Subject ◽  
Freezing Temperatures

Moisture in composite materials has been the subject of considerable interest in the past decade. Many studies have shown that moisture directly causes damage in graphite/epoxy composite materials. With the increasing use of such composites in various environments, an assessment of the effects of sub-freezing and/or cryogenic temperatures on composites containing moisture is needed. This article presents a summary of these effects and demonstrates that reductions in strength at low temperatures are not due to the formation of ice crystals, but instead are due to changes in the residual stresses caused by absorbed moisture.

A New Pipeline Repair System and Its Application in China

2008 ◽  
Author(s):  
Guo Liu ◽  
Xiuyun Wang ◽  
Minxu Lu
Keyword(s):  
Composite Materials ◽  
Carbon Fiber ◽  
Epoxy Composite ◽  
Cost Effective ◽  
Repair System ◽  
The Past ◽  
Repair Technology ◽  
Piping Systems ◽  
External Corrosion ◽  
Carbon Fiber Epoxy

For the past decade composite materials has been widely accepted as a repair method for damaged gas and liquid transmission pipelines. Composite wrap can serve as an alternative to the traditional pipeline repair practices such as pipeline replacement or the installation of full-encirclement steel split sleeves. A carbon-fiber/epoxy composite wrap system has been developed to rehabilitate and restore original operational strength to corroded and eroded pipelines and piping systems. This system is a permanent, cost-effective pipeline repair technology, suitable for non-leaking defects such as pits, dents, gouges, and external corrosion. This composite wrap system has been widely used in China for rehabilitations of numerous gas and petroleum pipelines.

Point and planar defects in the iron sulfide compounds Fe1-xS

1984 ◽  
Vol 42 ◽  
pp. 434-435
Author(s):  
Thao A. Nguyen
Keyword(s):  
Low Temperatures ◽  
Direct Evidence ◽  
Iron Sulfide ◽  
Planar Defects ◽  
Selective Area ◽  
Vacancy Ordering ◽  
Different Types ◽  
Lattice Images ◽  
The Subject ◽  
Beam Lattice

It is well known that the large deviations from stoichiometry in iron sulfide compounds, Fe1-xS (0≤x≤0.125), are accommodated by iron vacancies which order and form superstructures at low temperatures. Although the ordering of the iron vacancies has been well established, the modes of vacancy ordering, hence superstructures, as a function of composition and temperature are still the subject of much controversy. This investigation gives direct evidence from many-beam lattice images of Fe1-xS that the 4C superstructure transforms into the 3C superstructure (Fig. 1) rather than the MC phase as previously suggested. Also observed are an intrinsic stacking fault in the sulfur sublattice and two different types of vacancy-ordering antiphase boundaries. Evidence from selective area optical diffractograms suggests that these planar defects complicate the diffraction pattern greatly.

Pakistan’s Development: Successes, Failures, and Future Tasks (Presidential Remarks)

1997 ◽  
Vol 36 (4I) ◽  
pp. 321-331
Author(s):  
Sarfraz Khan Qureshi
Keyword(s):  
Indian Subcontinent ◽  
General Meeting ◽  
The Past ◽  
Past Half Century ◽  
The Social ◽  
The Subject ◽  
Golden Jubilee ◽  
Freedom Movement ◽  
Past Half ◽  
Do So

It is an honour for me as President of the Pakistan Society of Development Economists to welcome you to the 13th Annual General Meeting and Conference of the Society. I consider it a great privilege to do so as this Meeting coincides with the Golden Jubilee celebrations of the state of Pakistan, a state which emerged on the map of the postwar world as a result of the Muslim freedom movement in the Indian Subcontinent. Fifty years to the date, we have been jubilant about it, and both as citizens of Pakistan and professionals in the social sciences we have also been thoughtful about it. We are trying to see what development has meant in Pakistan in the past half century. As there are so many dimensions that the subject has now come to have since its rather simplistic beginnings, we thought the Golden Jubilee of Pakistan to be an appropriate occasion for such stock-taking.

TARP DVIEJŲ KOLONŲ: XVIII A. PABAIGOS – XIX A. PRADŽIOS VILNIAUS MASONŲ KASDIENYBĖ SIMBOLIKOJE

2018 ◽  
pp. 144-163
Author(s):  
Daiva Milinkevičiūtė
Keyword(s):  
Daily Life ◽  
The Other ◽  
Daily Routine ◽  
The Past ◽  
Secular World ◽  
National Characteristics ◽  
Conservative Christian ◽  
The Subject ◽  
The One ◽  
Craft Guilds

The Age of Enlightenment is defined as the period when the universal ideas of progress, deism, humanism, naturalism and others were materialized and became a golden age for freemasons. It is wrong to assume that old and conservative Christian ideas were rejected. Conversely, freemasons put them into new general shapes and expressed them with the help of symbols in their daily routine. Symbols of freemasons had close ties with the past and gave them, on the one hand, a visible instrument, such as rituals and ideas to sense the transcendental, and on the other, intense gnostic aspirations. Freemasons put in a great amount of effort to improve themselves and to create their identity with the help of myths and symbols. It traces its origins to the biblical builders of King Solomon’s Temple, the posterity of the Templar Knights, and associations of the medieval craft guilds, which were also symbolical and became their link not only to each other but also to the secular world. In this work we analysed codified masonic symbols used in their rituals. The subject of our research is the universal Masonic idea and its aspects through the symbols in the daily life of the freemasons in Vilnius. Thanks to freemasons’ signets, we could find continuity, reception, and transformation of universal masonic ideas in the Lithuanian freemasonry and national characteristics of lodges. Taking everything into account, our article shows how the universal idea of freemasonry spread among Lithuanian freemasonry, and which forms and meanings it incorporated in its symbols. The objective of this research is to find a universal Masonic idea throughout their visual and oral symbols and see its impact on the daily life of the masons in Vilnius. Keywords: Freemasonry, Bible, lodge, symbols, rituals, freemasons’ signets.

Performance Management Transformation

2020 ◽  
Keyword(s):  
Organizational Performance ◽  
Performance Management ◽  
High Performance ◽  
Best Practice ◽  
Call To Action ◽  
Daily Work ◽  
The Past ◽  
Great Debate ◽  
The Subject ◽  
New Research

No other talent process has been the subject of such great debate and emotion as performance management (PM). For decades, different strategies have been tried to improve PM processes, yielding an endless cycle of reform to capture the next “flavor-of-the-day” PM trend. The past 5 years, however, have brought novel thinking that is different from past trends. Companies are reducing their formal processes, driving performance-based cultures, and embedding effective PM behavior into daily work rather than relying on annual reviews to drive these. Through case studies provided from leading organizations, this book illustrates the range of PM processes that companies are using today. These show a shift away from adopting someone else’s best practice; instead, companies are designing bespoke PM processes that fit their specific strategy, climate, and needs. Leading PM thought leaders offer their views about the state of PM today, what we have learned and where we need to focus future efforts, including provocative new research that shows what matters most in driving high performance. This book is a call to action for talent management professionals to go beyond traditional best practice and provide thought leadership in designing PM processes and systems that will enhance both individual and organizational performance.

Anisotropic Elasticity

1996 ◽  
Author(s):  
T. T. C. Ting
Keyword(s):  
Composite Materials ◽  
Elastic Constants ◽  
Piezoelectric Materials ◽  
Anisotropic Materials ◽  
Anisotropic Elasticity ◽  
Stress Singularities ◽  
Comprehensive Survey ◽  
The Subject ◽  
Key Topics ◽  
First Time

Anisotropic Elasticity offers for the first time a comprehensive survey of the analysis of anisotropic materials that can have up to twenty-one elastic constants. Focusing on the mathematically elegant and technically powerful Stroh formalism as a means to understanding the subject, the author tackles a broad range of key topics, including antiplane deformations, Green's functions, stress singularities in composite materials, elliptic inclusions, cracks, thermo-elasticity, and piezoelectric materials, among many others. Well written, theoretically rigorous, and practically oriented, the book will be welcomed by students and researchers alike.

scholarly journals Shopping Centres, Cycling Accessibility and Planning—The Case of Nova Lund in Sweden

Urban Science ◽  
2020 ◽  
Vol 4 (4) ◽  
pp. 70
Author(s):  
Till Koglin ◽  
Lucas Glasare
Keyword(s):  
Conflicts Of Interest ◽  
Current Situation ◽  
Decision Makers ◽  
Power Structures ◽  
Literature Study ◽  
Shopping Centre ◽  
The Past ◽  
Whole Process ◽  
The Subject

This paper evaluates the history and cycling accessibility of Nova, a shopping centre established in Lund, Sweden, in 2002. The current situation was also analysed through observation and a literature review. Moreover, the study conducted a closer analysis of the history and role of the municipality based on further literature study and interviews with officials. The conclusion of the analysis indicates poor and unsafe bikeways caused by conflicts of interest between politicians, officials, landowners and the general public. It also depicts a situation in which the municipality’s master plan has been ignored, and, in contrast to the local goals, cycling accessibility at Nova has seen no significant improvement since the shopping centre was first established. The reasons for this, arguably, are a relatively low budget for bikeway improvements in the municipality, as well as a situation in which decision-makers have stopped approaching the subject, as a result of the long and often boisterous conflicts it has created in the past. Lastly, it must be noted that it is easy to regard the whole process of Nova, from its establishment to the current situation, as being symptomatic of the power structures between drivers and cyclists that still affect decision-makers at all levels.

scholarly journals Teaching Science in Today’s Society: The Case of Particle Physics for Primary Schools

Universe ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 169
Author(s):  
Cristina Lazzeroni ◽  
Sandra Malvezzi ◽  
Andrea Quadri
Keyword(s):  
Particle Physics ◽  
Primary Schools ◽  
Scientific Information ◽  
Decision Makers ◽  
Educational Institutions ◽  
The Public ◽  
The Past ◽  
Rapid Changes ◽  
The Subject ◽  
Ongoing Project

The rapid changes in science and technology witnessed in recent decades have significantly contributed to the arousal of the awareness by decision-makers and the public as a whole of the need to strengthen the connection between outreach activities of universities and research institutes and the activities of educational institutions, with a central role played by schools. While the relevance of the problem is nowadays unquestioned, no unique and fully satisfactory solution has been identified. In the present paper we would like to contribute to the discussion on the subject by reporting on an ongoing project aimed to teach Particle Physics in primary schools. We will start from the past and currently planned activities in this project in order to establish a broader framework to describe the conditions for the fruitful interplay between researchers and teachers. We will also emphasize some aspects related to the dissemination of outreach materials by research institutions, in order to promote the access and distribution of scientific information in a way suited to the different age of the target students.

Sign in / Sign up

Export Citation Format

Share Document