Mechanical Behavior of Heat Activated Film Adhesives

2021 ◽  
Author(s):  
Prabhat Janamanchi ◽  
Abhijit Dasgupta ◽  
Narendra Singh

Abstract Heat activated film (HAF) adhesives enable the bonding of materials that are difficult to bond with conventional adhesives where one of the substrates is flexible. Although they are traditionally found in the context of industrial and structural applications, they are increasingly finding use in in electronic products. This paper provides a preliminary evaluation of the mechanical behavior of HAFs. Two commercial polyurethane HAF formulations (designated as HAF-II and HAF-III, for the purpose of this paper) were evaluated to assess the dependence of the mechanical properties on phase transitions and on the thermal exposure history of the material. Both factors were found to play a significant role in determining the overall usability of the materials. The melting transition occurs under 50°C for both materials, after which their stiffness drops significantly. Among the two, HAF-III is preferable as it undergoes a delayed melting transition, effectively extending the usable operating temperature range. As with any adhesive, there are several other factors that can influence the performance of adhesives such as post-curing age, storage, and curing conditions to name a few. The impact of these factors on the material’s strength is also discussed in brief and a recommendation for favorable conditions is provided.

2005 ◽  
Vol 29 (3) ◽  
pp. 68-81 ◽  
Author(s):  
Jeanette Allen ◽  
Panos Vostanis

Jeanette Allen and Panos Vostanis describe the set-up and preliminary evaluation of a seven-week training programme for foster carers and supervising social workers based on attachment theory. It has long been recognised that parenting children with complex and challenging needs in a family setting is extremely demanding, with research indicating that foster carers' lack of confidence in managing such demands is a significant factor in placement breakdown. This study suggests that attachment theory provides a useful model to help carers understand and respond to the complex difficulties presented by children with a history of abuse and trauma, and that the provision of a conceptual framework may be a significant factor in improving foster carers' confidence to manage the difficulties presented by the children in their care. The clinical implications of this evaluation are discussed.


Crisis ◽  
2016 ◽  
Vol 37 (4) ◽  
pp. 265-270 ◽  
Author(s):  
Meshan Lehmann ◽  
Matthew R. Hilimire ◽  
Lawrence H. Yang ◽  
Bruce G. Link ◽  
Jordan E. DeVylder

Abstract. Background: Self-esteem is a major contributor to risk for repeated suicide attempts. Prior research has shown that awareness of stigma is associated with reduced self-esteem among people with mental illness. No prior studies have examined the association between self-esteem and stereotype awareness among individuals with past suicide attempts. Aims: To understand the relationship between stereotype awareness and self-esteem among young adults who have and have not attempted suicide. Method: Computerized surveys were administered to college students (N = 637). Linear regression analyses were used to test associations between self-esteem and stereotype awareness, attempt history, and their interaction. Results: There was a significant stereotype awareness by attempt interaction (β = –.74, p = .006) in the regression analysis. The interaction was explained by a stronger negative association between stereotype awareness and self-esteem among individuals with past suicide attempts (β = –.50, p = .013) compared with those without attempts (β = –.09, p = .037). Conclusion: Stigma is associated with lower self-esteem within this high-functioning sample of young adults with histories of suicide attempts. Alleviating the impact of stigma at the individual (clinical) or community (public health) levels may improve self-esteem among this high-risk population, which could potentially influence subsequent suicide risk.


Author(s):  
C. Claire Thomson

This chapter traces the early history of state-sponsored informational filmmaking in Denmark, emphasising its organisation as a ‘cooperative’ of organisations and government agencies. After an account of the establishment and early development of the agency Dansk Kulturfilm in the 1930s, the chapter considers two of its earliest productions, both process films documenting the manufacture of bricks and meat products. The broader context of documentary in Denmark is fleshed out with an account of the production and reception of Poul Henningsen’s seminal film Danmark (1935), and the international context is accounted for with an overview of the development of state-supported filmmaking in the UK, Italy and Germany. Developments in the funding and output of Dansk Kulturfilm up to World War II are outlined, followed by an account of the impact of the German Occupation of Denmark on domestic informational film. The establishment of the Danish Government Film Committee or Ministeriernes Filmudvalg kick-started aprofessionalisation of state-sponsored filmmaking, and two wartime public information films are briefly analysed as examples of its early output. The chapter concludes with an account of the relations between the Danish Resistance and an emerging generation of documentarists.


2014 ◽  
Vol 1 (1) ◽  
pp. 31-36 ◽  
Author(s):  
O. Zhukorskiy ◽  
O. Gulay ◽  
V. Gulay ◽  
N. Tkachuk

Aim. To determine the response of the populations of Erysipelothrix rhusiopathiae and Leptospira interrogans pathogenic microorganisms to the impact of broadleaf cattail (Thypha latifolia) root diffusates. Methods. Aqueous solutions of T. latifolia root diffusates were sterilized by vacuum fi ltration through the fi lters with 0.2-micron pore diameter. The experimental samples contained cattail secretions, sterile water, and cultures of E. rhusiopathiae or L. interrogans. The same amount of sterile water, as in the experimental samples, was used for the purpose of control, and the same quantity of microbial cultures was added in it. After exposure, the density of cells in the experimental and control samples was determined. Results. Root diffusates of T. latifolia caused an increase in cell density in the populations of E. rhusiopathiae throughout the whole range of the studied dilutions (1:10–1:10000). In the populations of the 6 studied serological variants of L. interrogans spirochetes (pomona, grippotyphosa, copenhageni, kabura, tarassovi, canicola), the action of broadleaf cattail root diffusates caused the decrease in cell density. A stimulatory effect was marked in the experimental samples of the pollonica serological variant of leptospira. Conclusions. The populations of E. rhusiopathiae and L. interrogans pathogenic microorganisms respond to the allelopathic effect of Thypha latifolia by changing the cell density. The obtained results provide the background to assume that broadleaf cattail thickets create favorable conditions for the existence of E. rhusiopathiae pathogen bacteria. The reduced cell density of L. interrogans in the experimental samples compared to the control samples observed under the infl uence of T. latifolia root diffusates suggests that reservoirs with broadleaf cattail thickets are marked by the unfavorable conditions for the existence of pathogenic leptospira (except L. pollonica).


Author(s):  
Bryan D. Palmer

This article is part of a special Left History series reflecting upon changing currents and boundaries in the practice of left history, and outlining the challenges historians of the left must face in the current tumultuous political climate. This series extends a conversation first convened in a 2006 special edition of Left History (11.1), which asked the question, “what is left history?” In the updated series, contributors were asked a slightly modified question, “what does it mean to write ‘left’ history?” The article charts the impact of major political developments on the field of left history in the last decade, contending that a rising neoliberal and right-wing climate has constructed an environment inhospitable to the discipline’s survival. To remain relevant, Palmer calls for historians of the left to develop a more “open-ended and inclusive” understanding of the left and to push the boundaries of inclusion for a meaningful historical study of the left. To illustrate, Palmer provides a brief materialist history of liquorice to demonstrate the mutability of left history as a historical approach, rather than a set of traditional political concerns.


2020 ◽  
Vol 5 (3) ◽  
pp. 20-24
Author(s):  
Durdona Karimova ◽  

This article discusses the theoretical and practical foundations of the concept of sociolinguistics and the importance of this field in the study of the impact of society on language. It also describes the views of linguists in this regard, the history of the origin and development of the filed, its connection with other disciplines, and explains in detail the sociolinguistic issues with practical examples.In addition, the terms as macro-sociolinguistics and micro-sociolinguistics and sociolinguistic competence are explained.


Author(s):  
Zulpadli Zulpadli

This paper briefly and through theoretical studies will discuss simply the problems formulated, the impact of globalization on Character education in Indonesia, as well as the paradigm of PKN learning and Character education challenges for the younger generation. It is on the ground by the declining awareness and moral values, as well as to increase the values of the characters seen in the young generations. Civic education in Indonesia has been running throughout the history of Indonesian independence, and has gone through various stages and arms, it certainly demands greater hard work of teachers to be able to increase the values of Pancasila and love of the homeland, and practice the character values which is based on the noble values of Indonesian culture into Indonesian youth.


2019 ◽  
Author(s):  
Daryl Brian O'Connor

Suicide is a global health issue accounting for at least 800,000 deaths per annum. Numerous models have been proposed that differ in their emphasis on the role of psychological, social, psychiatric and neurobiological factors in explaining suicide risk. Central to many models is a stress-diathesis component which states that suicidal behavior is the result of an interaction between acutely stressful events and a susceptibility to suicidal behavior (a diathesis). This article presents an overview of studies that demonstrate that stress and dysregulated hypothalamic-pituitary-adrenal (HPA) axis activity, as measured by cortisol levels, are important additional risk factors for suicide. Evidence for other putative stress-related suicide risk factors including childhood trauma, impaired executive function, impulsivity and disrupted sleep are considered together with the impact of family history of suicide, perinatal and epigenetic influences on suicide risk.


1989 ◽  
Vol 6 (2) ◽  
pp. 319-328
Author(s):  
Salahudeen Yusuf

The history of Islam in part of what is known today as Nigeria datesto about the loth Century. Christianity dates to the late 18th Century. Bythe middle of the 19th Century, when Nigerian newspapers began to appearon the streets of Nigeria, both religions had won so many followers and extendedto so many places in Nigeria that very few areas were untouched bytheir influence. The impact of both religions on their adherents not only determinedtheir spiritual life, but influenced their social and political lives aswell. It therefore became inevitable that both religions receive coverage frommost of the newspapers of the time. How the newspapers as media of informationand communication reported issues about the two religions is thetheme of this paper.Rationale for the StudyThe purpose of this study is to highlight the context in which such earlynewspapers operated and the factors that dictated their performance. Thisis because it is assumed that when a society faces external threat to its territory,culture, and independence, all hands (the press inclusive) ought tobe on deck to resist the threat with all might. Were newspapers used as verbalartillery and how did they present each religion? It is also assumed thatin a multireligious society a true press should be objective and serve as avanguard in the promotion of the interest of the people in general and notcreate or foster an atmosphere of religious conflict. The study also aims atfinding out whether the papers promoted intellectual honesty and fosteredthe spirit of unity particularly when the society was faced with the encroachmentof the British who posed a threat to their freedom, culture, economy ...


Author(s):  
N. G. Krasavtseva

The article examines the evolution of the population’s priorities in relation to housing, examines the legal regulation and socio-cultural aspects of public housing construction at various stages of the history of the USSR. The research reveals the impact of the developing industry on the country’s economy.


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