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The paper aims to present the original and easy for application methods of mechanical strength and electrical properties examination of conductive adhesives and adhesive joints at room as well as at liquid nitrogen temperatures.

The Epoxy Technology EPO‐TEK E4110 and EPO‐TEK H20E adhesives were investigated both in the form of the loose rod and as the printed layers on alumina substrates. Additionally, the mechanical and electrical properties of adhesive joints in low temperatures were investigated, where their characteristics depended on the physical properties of joined elements.

The results indicate the substantial influence of the substrate material on the adhesive resistivity. The joints samples were exposed to multiple thermal shocks in the range from room down to liquid nitrogen temperatures and it was observed that the joints strength and resistance stability could be reached in determined curing conditions of the adhesive.

It is generally stated that tested adhesives can be fully suitable for work in low temperatures. However, it should be underlined that these adhesives' properties change after cooling them down to the liquid nitrogen temperature – the strength growths and the resistance diminishes (about few times).

The paper examines mechanical strength and electrical properties of conductive adhesives and adhesive joints at various temperatures.

Investigations were aimed at the evaluation of degradation mechanisms in ultrasonically welded joints of AlSi1 per cent wire (25 μm in diameter) and Au substrate (100 μm thick), relatively thick elements, exposed to high temperature of 300°C up to 100 h. Thermally activated Al diffusion into Au generates the formation of intermetallic compounds in the area of the bond interface. With the longer thermal exposure the expansion and transformation of intermetallic compounds is observed. The characteristic “intermetallic compounds core” is formed, which from one side penetrates into the wire material and from another spreads deeply into the Au substrate up to enhancing band of Kirkendall voids.

Investigations were aimed at evaluation of assembly properties of conductive layers cofired with LTCC substrates. The usefulness of these layers for low‐temperature soldering, joining with adhesives or for wire bonding was tested. The samples were manufactured from inks and glass‐ceramic sheets from three known LTCC producers. Different material combinations and various temperature‐time profiles of firing were used. The investigations were on: wettability measurements of conductive layers, evaluation of the layer resistance to dissolution, the deep analyses of particular wire bonding processes and the joint quality assessment at the time of welding, and the joint strength measurements. In the case of adhesive connections the resistance measurements of joints were applied. Scanning electron microscopy analyses were applied and metallographic examinations of sample cross‐sections were undertaken. The results of the investigations allowed us to choose films with appropriate bonding properties, and to explain the mechanism of joint failure.

The International Electronic Components Show in Paris in November, 1983, provided the occasion for a very successful meeting of ISHM‐France which attracted 170 attendees. The following presentations were given:

The purpose of the paper was to present a comparative study on the microstructure and magnetoelectric effect of new magnetoelectric composites based on TbFe₂ compound and Ni_0.3Zn_0.62Cu_0.08Fe₂O₄, CoFe₂O₄ ferrites as a magnetostrictive phase, Pb(Fe_1/2Ta_1/2)O₃ (PFT), Pb(Fe_1/2Nb_1/2)O₃ relaxors as a ferroelectric phase and polyvinylidene fluoride (PVDF) as piezoelectric phase.

The ceramic components of composites were prepared by the standard solid-state reaction method. The intermetallic compound TbFe₂ was prepared with an arc melting system with a contact-less ignition in a high purity argon atmosphere. The metal – ceramic – polymer composites were prepared in a container in which powder of PVDF were dissolved in N,N-dimethylformamide with continuous mixing and at the controlled temperature. Ceramic composites were prepared as bulk samples and multilayer tape cast and co-sintered laminates. The microstructure of the composites was investigated using scanning electron microscopy (SEM). The magnetoelectric effect of the composites was evaluated at room temperature by means of the dynamic lock-in method.

SEM analysis revealed a dense, fine-grained microstructure and uniform distribution of the metallic, ferrite and relaxor grains in the bulk composites. The SEM image for multilayer composite illustrates the lack of cracks or delaminations at the phase boundaries between the well-sintered ferrite and relaxor layers. For all studied composites, the magnetoelectric coefficients at a lower magnetic field increase, reaches a maximum and then decreases.

The progress in electronic technology is directly linked to advances made in materials science. Exploring and characterizing new materials with interesting magnetoelectric properties, in the rapidly growing field of functional materials, is an important task. The paper reports on processing, microstructure and magnetoelectric properties of novel magnetoelectric composites.

The goal of this chapter is to address the importance of helping teachers develop an understanding of LGBTQ+ issues and ways to create inclusive classrooms for LGBTQ+ students with particular attention to how LGBTQ+ identities/experiences can be valued and visible through literary and literacy practices. The issues addressed in this chapter are grounded in queer theory and intersectionality, which provide a space for challenging heteronormative environments in many schools as well as acknowledging the complex intersectionality of diverse identities. This framework is unpacked so readers can see how it supports instructional practices. Theory and literature inform discussion of the move in the literacy profession toward LGBTQ+ -inclusive mindsets and pedagogies. They further inform practical implications and examples provided by the author. A major issue of our time is LGBTQ+ inclusion in schools and the role of teachers in implementing literacy practices that address the needs of LGBTQ+ students and making visible their diverse identities. For the field of literacy, this is evidenced in the revision of Standard 4 Diversity and Equity in the International Literacy Association’s (ILA) Standards for the Preparation of Literacy Professionals 2017 (Standards 2017). ILA Standards 2017, which will be released in 2018, require programs preparing literacy professionals to develop candidates’ knowledge of queer theory and literacy practices inclusive of diverse students, with diversity including sexual orientation, gender identity, and gender expression. Further, ILA Standards 2017 acknowledge intersectionality across forms of diversity and that a rich understanding of diversity improves the quality of teaching and learning within and across classrooms, schools, and communities. This chapter expands on these topics and offers foundational content and resources to help literacy teacher educators, candidates in literacy programs, and other stakeholders to answer this call for building a literacy field that is welcoming, inclusive, and equity-oriented. Developing the knowledge base about LGBTQ+ issues, including theoretical foundations, social justice teaching mindsets, and concrete pedagogical literacy practices that build inclusive classrooms, can be an accessible, meaningful, and fruitful endeavor that will enrich literacy education programs and the learning communities in which literacy professionals work. Teacher educators and teachers can utilize book choices, approaches to classroom discussion and assignments, and school initiatives to build a learning environment that values LGBTQ+ students’ identities and experiences and disrupts heteronormativity in the curriculum. Multiple examples of how this can be done are offered. Understanding intersectionality also helps teacher educators and teachers see how forms of diversity are not silos. Individuals’ identities are comprised of various aspects. The topics discussed in this chapter center on LGBTQ+ issues but are applicable beyond just this scope.

According to the growing role of stakeholders in the implementation of public-private partnership (PPP) initiatives, the purpose of this study is to diagnose the maturity of PPPs in Poland, taking into account the range of stakeholders’ participation in public-private initiatives.

The introductory study on the stakeholders of PPPs has been based on the report analysis of Polish initiatives and the case studies’ comparative analysis. The cases represent touristic projects realized within PPPs.

The results of the study indicate that the PPPs’ personal context, though recognized internationally, is to a very low extent present in the Polish case. As the PPP market is still in the process of development, the stakeholders’ issue should be taken into consideration in the processes of the PPP development in Poland.

As regional development is continuously a key issue, especially in rural areas context, the PPP initiatives are of great importance, and therefore the discussion of pros and cons in this context may contribute to the legislation at the regional level.

The study sheds some light and gives some interesting perspectives on the issue of the personal context of PPPs and social capital. Also, the text describes the path of developing PPPs in Poland and especially the touristic projects. The research part presents the original case study comparative analysis based on table-oriented form and as such enables the new way of contextual analysis.

The purpose of this paper is to investigate the feasibility of using land grid array (LGA) solder joints as a second-level interconnection option in low-temperature co-fired ceramic (LTCC)/printed wiring board (PWB) assemblies for telecommunication applications. The characteristic behaviour of two commercial lead-free solder materials (Sn4Ag0.5Cu and Sn3Ag0.5Cu0.5In0.05Ni) in reflow processes and thermal cycling tests are also evaluated.

The effect of the reflow temperature profile on voiding in two lead-free solders in LTCC/PWB assemblies was investigated using X-ray and scanning electron microscopy (SEM) investigations. The test assemblies were fabricated and exposed to a temperature cycling test (TCT) in a 0-100°C or −40 to 125°C temperature range. Organic PWB material with a low coefficient of thermal expansion (CTE) was primarily used. In addition, to compare LGA assemblies with low and high global thermal mismatches, an LTCC module/FR-4 assembly was also fabricated and exposed to a TCT in a 0-100°C temperature range. The characteristic lifetime of the test assemblies was determined using DC resistance measurements. The failure mechanisms of the interconnections were verified using scanning acoustic microscopy, SEM and finite element (FE)-SEM investigations.

This work showed that the solderability of AgPt-metallized LTCC modules was poor, resulting in excessive voiding. This problem was avoided by using pre-tinned modules. In the test assemblies, the Sn4Ag0.5Cu joints had a lower void content and a higher characteristic lifetime compared with the Sn3Ag0.5Cu0.5In0.05Ni joints. Furthermore, it was observed that the Sn3Ag0.5Cu0.5In0.05Ni joints were more prone to fail along the interface between the Ag₃Sn layer and the solder matrix than were the Sn4Ag0.5Cu joints. It was assumed that the observed difference in the primary failure mechanisms resulted in the decreased lifetime duration of the SnAgCu-InNi/Arlon in both temperature cycling conditions.

The results proved that the solderability of both solders in AgPt-metallized modules in a typical surface mount technology process was poor; however, the solderability of the test modules can be notably enhanced with pre-tinned pads. This work also demonstrated the effect of the metallization/solder pair on the failure mechanisms and failure rate in LTCC/PWB assemblies with LGA joints; the work also proved in the TCT, over a temperature range of 0-100°C, that using the present LGA joints in LTCC/PWB assemblies with a high global thermal mismatch did not increase the lifetime duration of the joints to the preferred level (3,000 cycles), whereas the performance of these joints was adequate in assemblies with a low global thermal mismatch. Moreover, the results indicated that using the LGA joint configuration enhanced the reliability of the LTCC/PWB assemblies compared with similar assemblies with collapsible ball grid array solder spheres.