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Fluxless wave soldering in a nitrogen atmosphere was investigated for epoxy‐fibreglass circuit board coupons having bare copper and solder‐coated through‐holes. The Reduced Oxide Soldering Activation (ROSA™) pretreatment was found to consistently provide good hole filling and through‐hole solder joints of excellent appearance. For preheated coupons, low levels of residual oxygen and short exposure to air after the ROSA treatment were found to have no effect

The recently developed Reduced Oxide Soldering Activation (ROSA™) method is shown to be compatible with long‐term use with mass soldering processes. Prototype regeneration cells operated for as long as six months with minimal maintenance retained their effectiveness for providing short wetting times under a variety of perturbations. The operating window for the process is wide and component degradation caused by exposure to the fully charged solution is minimal. The ROSA treatment provides soldering performance comparable to that attainable with a fully activated rosin flux and offers the promise of providing low soldering defect rates without the use of CFC solvents.

Some universities have a commitment to both academic education and sustainable development, and the sustainable development goals can support several sustainable actions that universities may take as principles and attitudes. From this perspective, the purpose of this study is to present environmentally sustainable practices at a federal university in Brazil and to analyze and discuss the potential environmental impacts associated with an environmentally sustainable practice implemented using life cycle assessment (LCA) and its benefits for the university’s decision-makers.

To accomplish that, the study combines a description of environmentally sustainable practices at the 13 campuses of the Universidade Tecnológica Federal do Paraná (UTFPR) in terms of education, water and electricity consumption, waste management and emissions. As a result of this analysis, one campus identified that a high volume of disposable plastic cups were being disposed of, for which the use of reusable plastic cups was introduced. In addition, an LCA study (ISO 14040:2006 and 14044:2006) quantified the benefits of the introduction of said reusable plastic cups.

The results show that the university is working on environmentally sustainable initiatives and policies to become greener. At the same time, using a systematic LCA made it possible to measure that replacing disposable plastic cups for reusable ones reduced waste generation but increased water consumption on the campus. Faced with this, a sensitization was carried out to reduce water consumption. Finally, the current study provides lessons on the environmental performance to universities interested in sustainable practices, fostering perspectives for a better world. The findings of this study encourage organizations to accomplish environmental actions toward greener universities. The study shows that institutions need to be reflective and analytical about how even “greening” measures have impacts, which can be mitigated if necessary.

The sustainable practical implications were reported, and an LCA was conducted to assess potential environmental impacts of reusable plastic cups. It was identified that raw material production is the phase that generates most environmental impacts during the life cycle of the product, along with the consumer use phase, due to the quantity of water used to wash the reusable cups. In addition, the practical contributions of this study are to provide insights to institutions that aim to use environmental actions, i.e. suggestions of sustainable paths toward a greener university.

This is one of the first studies to investigate and discuss sustainable practices at UTFPR/Brazil. The study assessed one of the practices using a scientific technique (LCA) to assess the impacts of reusable plastic cups distributed to the students of one of the 13 campuses. Although there are other studies on LCA in the literature, the value of this study lies in expanding what has already been experienced/found on the use of LCA to assess environmental practices in university campuses.

Organic and immersion metallic coatings are being used as a replacement for the hot air solder level (HASL) process. Use of these coatings provides advantages for both the fabricator and assembler. Advantages to assemblers include flatter pads (0.25‐0.5 micron thickness), no limitations on fine pitch or small hole cleaning, and greater solder joint strength. Advantages to the fabricator include lower operating costs, little or no rejects/rework, reduced safety hazard and a more environmentally friendly process. Current problems associated with the organic and immersion coatings include the inability to assess the solderability of the bare copper or the integrity of the coating (organic). These coatings also present a critical concern due to their reduced shelf life and potential inability to survive mishandling in manufacturing. Real time, non‐destructive methods of rapidly assessing the integrity these coatings are currently not available to the electronics industry. Surface Spectroscopy measurement techniques have the potential to measure the structure and characteristics of the organic and metallic coatings, and surface oxides that develop with time and temperature. The measurement techniques are rapid, non‐contact, and relatively inexpensive to make when compared to existing methods. Surface Spectroscopy can also provide critical surface information that is needed to troubleshoot solderability problems. The American Competitiveness Institute in association with the Navy EMPF program is working with several industry partners to develop a usable surface spectroscopy tool that will assess the quality and integrity of the coatings and correlate that reading with a solderability evaluation.

Poland’s political and economic transformation after 1989 brought the logic of the neoliberal market into the educational system. These changes, however, were far from the real liberal free market and instead relied on bureaucratic and technocratic local-level apparatus as well as supranational supports (the EU). Moreover, instead of enhancing post-socialist education to bring them up to the level of the core territories, this process pushed education out to the (semi?)periphery. The purpose of this paper is to present selected examples of alternative non-mainstream models of education.

Elements analyzed include: non/academic discourses, with particular emphasis on academic texts, media material and public debates concerning the topic in question.

Two related fields and levels ought to be distinguished: the descriptive level, focused on presenting non-mainstream educational institutions and initiatives, within the socioeconomic context of Poland’s post-socialist transformation; the normative level, with recommendations for policymakers, NGOs and educational activists.

Appreciation of systems parallel and alternative to the neoliberal and technocratic mainstream education system in Poland, with a view to encouraging both policymakers to recognise and develop such initiatives, and members of Polish civil society to create and participate in such forms of education.

Most scholars focus on mainstream education, with a number of exceptions, largely those engaged in the parallel models. This neoliberal model of education is accepted or critically examined, but its technocratic base is not recognised. This text is therefore ground-breaking in that it describes the real mechanisms of the Polish educational system in transition and provides a normative account and recommendations.

The unique advantages of confocal microscopy are used to explore four cases of interest: (i) voids in solder (depth and surface texture determined), (ii) steam vs ambient aged solder coupons (significant differences detected), (iii) integrated circuit construction (sub‐surface contamination by µm‐size particles observed) and (iv) circuit boards and solder pads (non‐destructive optical sectioning through no‐wash flux layers). It is shown that confocal microscopy strongly complements SEM (scanning electron microscopy); SEM alone presents an incomplete description of a solder surface and in fact can sometimes produce misleading results.

A series of composite solders in 63/37 Sn/Pb was prepared: Cu₆ Sn₅ (10, 20, 30 wt%); Cu₃ Sn (10, 20, 30 wt%); Cu (7.6 wt%); Ag (4 wt%); and Ni (4 wt%). These composite solders were prepared by two procedures: (A) admixture with solder paste; and (B) admixture with molten solder. The original particulates and the final composite solders were analysed and characterised by SEM (scanning electron microscopy) EDX (energy dispersive X‐ray), and ESCA (electron spectroscopy for chemicals analysis); or XPS (X‐ray photoelectron spectroscopy). A variety of morphological characterisations, intermetallics and porosities were noted. Good wetting was noted in all cases, and porosity was greater for method (A). The particulates all exhibited excellent binding to the solder matrix.

This paper aims to describe a shape optimization for hyperelastic axisymmetric structure with an exact sensitivity method.

The whole shape optimization process is carried out by integrating a closed geometric shape in the real space R2 with boundaries defined by B-splines curves. An exact sensitivity analysis and a mathematical programming method (SQP: Sequential Quadratic Programming) are implemented. The design variables are the control points' coordinates which minimize the Von-Mises criteria, with a constraint that the total material volume of the structure remains constant. The feasibility of the proposed methods is carried out by two numerical examples. Results show that the exact Jacobian has an important computing time reduction.

Numerical examples are presented to illustrate its performance.

In this work, the sensitivity performance is computed using two numerical methods: the efficient finite difference scheme and the exact Jacobian.

To evaluate the oxide formation characteristics of tin (Sn) as a function of conditioning treatment and define a conditioning methodology that rapidly produces a tin oxide thickness and oxide species morphology similar to those formed in ambient oxidation.

Electrochemical reduction analysis and scanning electron microscopy techniques were utilized to identify tin oxide species and oxide quantities on tin samples which were subjected to a variety of conditioning methodologies.

Tin oxide species were identified and oxide quantities measured. Comparisons of tin oxide species/quantities were completed for the different conditioning methodologies used and for other industry oxide investigations. The following conclusions were reached: all conditioning methodologies produced both SnO and SnO₂ tin oxide species; steam conditioning produced the thickest oxides; the conditioning methodologies investigated were found to produce oxide thicknesses similar to those formed under ambient conditions.

Further investigation would be beneficial using this study as a foundation. Additional conditioning methodologies and a larger selection of various tin surfaces would provide a future understanding of the impact of oxide species and thickness on solderability.

The electronics industry has attempted to “predict” a surface's susceptibility to oxidation by using accelerated conditioning techniques. An understanding of the formation of tin oxidation products created by accelerated conditioning techniques could be highly beneficial to the electronics industry. The standardization and use of a realistic accelerated conditioning technique would reduce testing cycle time, increase the predictability and consistency of test results, and lower testing costs.

This paper was incorporated into an original electronics manufacturer's solderability testing/analysis procedures, and the results are being utilized by the electronics industry solderability specification task groups/committees.

The purpose of this paper is to report on a life cycle assessment (LCA)-based ecodesign teaching practice via university-industry collaboration in an industrial engineering undergraduate course.

A new course was designed and taught in the Industrial Engineering undergraduate course of a Federal University in Brazil. The course comprised explanatory lectures and a practical project developed in a partnership between the university and an industry partner where students had to develop Ecodesign proposals based on LCA to improve the environmental profile of both solid and reticulated paint brushes. To that end, students used the LCA software tool Umberto NXT v.7.1.13 (educational version), where they modeled the life cycle of four plastic brushes and assessed it using the impact categories of climate change and resource consumption, and the Ecoinvent v.3.3 database. After course completion, students, professors and industry collaborators were asked to provide feedback on the project performance and expectations.

The course design used was welcomed by both students and the industry partner. Students found the novel approach intriguing and useful to their future careers. The results also exceeded the industry partner’s expectations, as students formulated valuable insights. Professors observed that learning was made easier, as content was put into practice and internalized more easily and solidly. The approach was found to be a win-win-win.

Students acquired a fair share of knowledge on sustainability issues and potential existing trade-offs, which is valuable to industrial practices. The industry noticed the valuable contributions that academia can provide. The university profited from providing students with a real case challenging traditional teaching methods.

To the best of the authors’ knowledge, this is one of the first case studies to show how LCA and ecodesign teaching practice can support sustainability learning in an industrial engineering undergraduate course.