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Article
Publication date: 1 January 1989

D.A. Vidusek

Line widths are rapidly shrinking and the complexities of boards place increased demands on the resolution capabilities of the photoresists. A new technology is emerging…

Abstract

Line widths are rapidly shrinking and the complexities of boards place increased demands on the resolution capabilities of the photoresists. A new technology is emerging that offers the user unparalleled resolution, a completely aqueous system, and complete, uniform, three‐dimensional coverage of the panel. The unique properties of this system result from the extraordinary method of application of the photoresist. Electrophoresis, or electrocoating, allows the deposition of a very thin, uniform, highly chemically resistant photoresist layer. Any exposed conductive surface, including scratches or other panel imperfections, are coated. The combination of a very thin layer and no cover sheet allows the printing of sub‐mil geometries without the need for a collimated light source. This new application offers the user high yields, both from the chemistry and in circuit yields. Even more so, the resolution capabilities offer opportunities beyond the limitations of dry film and other liquid resists. The photoresist no longer needs to be the gating factor in process capability.

Details

Circuit World, vol. 15 no. 2
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 1 March 2002

John Gebhardt, Keith Waryold, Dave Oglesby and John Graves

The demand for higher operating speeds and increasing densification in electronic packages is driving designers to reduce feature sizes in order to accommodate increases…

Abstract

The demand for higher operating speeds and increasing densification in electronic packages is driving designers to reduce feature sizes in order to accommodate increases in I/O counts. Consequently, printed circuit board manufacturers are turning to new manufacturing techniques and new materials in order to meet these demands from their customers. Sequential build‐up is one such technique and a plethora of new materials is available to support these innovative routes to high‐density interconnect circuitry. The basic concept involves the addition of extra layers of dielectric and copper on to a multi‐layered board. The additional circuitry is then connected to the underlying board using suitably formed microvias. Focuses on the metallization of microvias using a straight‐through horizontal metallization process. Particular emphasis is placed on the importance of equipment design, the chemistry of the solutions used and optimization of fluid exchange to ensure good coverage of these small features.

Details

Circuit World, vol. 28 no. 1
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 6 February 2019

Da-Hai Xia and Jing-Li Luo

Corrosion is considered as one of the issues that threaten the safe operation of steam generator (SG) tubing. Some sulfur-related specie can cause corrosion degradation of…

Abstract

Purpose

Corrosion is considered as one of the issues that threaten the safe operation of steam generator (SG) tubing. Some sulfur-related specie can cause corrosion degradation of SG tubing. Sulfur-induced corrosion of SG alloys in high temperature and high-pressure water is one of the most complicated processes. The purpose of this study is to study the effect of reduced sulphur on passive film properties of steam generator (SG) tubing.

Design/methodology/approach

In this paper, the effects of reduced sulfur on passive film properties of SG tubing were reviewed from the aspects of thermodynamic calculations and experimental.

Findings

Thermodynamic calculations are mainly presented by E-pH diagrams, volt equivalent diagrams and species distribution curves. The stability of sulphur species highly depends on temperature, solution pH, and electrochemical potential. Experimental data indicated that reduced sulfur species can interact with the passive film, which led to changes in film thickness, film structure, semiconductivity and pitting growth rate.

Originality/value

The state-of-the-art discussed in this paper gives basis for resolving engineering problems regarding with sulfur-induced corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 27 May 2014

TomaszLiskiewicz and William M. Cox

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Abstract

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Anti-Corrosion Methods and Materials, vol. 61 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 18 April 2020

Maria Laura Frigotto and Pamela Palmi

This paper aims to contribute to the understanding of novelty emergence in the context of an “off-line” open innovation system. Several contributions address novelty…

Abstract

Purpose

This paper aims to contribute to the understanding of novelty emergence in the context of an “off-line” open innovation system. Several contributions address novelty generation implying open innovation that is typically mediated by IT systems, while fewer address open innovation that takes place off-line, through new forms of collaboration happening in the so-called “physical spaces” and in widespread creativity contexts involving whole cities and territories. This research aims to clarify what the critical elements for novelty generation are, and how and why they interact in producing novelty.

Design/methodology/approach

This paper presents the case study of the Blackshape, a high-tech start-up that has become the Italian symbol of a new bottom-up economy that is grounded on high-education, a mix of territorial competencies and young initiative, and produces the development or growth of territories experiencing present or foreseen economic retardation for various reasons. This is a case in which novelty is emergent and takes place through exaptation. The case is used to elaborate an inductive understanding of the process of novelty generation through exaptation and follows a “conceptual composition” format (Berends and Deken, 2019).

Findings

This paper shows that initiatives building widespread creativity on the territory play a prominent role for emergent novelty generation, as they provide the context that sustains the efforts to keep on trying of entrepreneurs, welcomes unforeseen interaction and keeps interesting people on the territory that can be involved in random encounters. This paper adds that crucial contributions for the definition of the innovative project come from contributors that are expected to provide suggestions in other areas. Such prominent contributors are engaged in a sense “by mistake”, and here the randomness perceived by the actors experiencing it, because they are perceived to be able to provide some contributions, while they provide others that are more important to the project. This paper argues that such “perceived randomness” sustains a mechanism of selection of novelty generation partners that allows to go beyond the ability of actors themselves to design and foresee other actors’ contribution into the project. Finally, two other elements play a role: how the project is narrated, as well as, how the entrepreneurial team communicates their entrepreneurial competence for the project.

Research limitations/implications

This theoretical understanding builds on only one case study; further research might validate the critical role of our understanding of novelty generation elements and help develop their dynamics further.

Practical implications

Many elements in our understanding of novelty generation have typically been understood as resulting from luck and randomness, leaving, therefore, very little hope to actors’ interest in supporting them. This paper claims that such elements and such dynamics can be sustained and novelty generation can indirectly be supported, for instance, by suggesting a high openness and sharing of one’s own project even to accidentally encountered actors, as one’s own ability to foresee how they might contribute to the project is very poor.

Originality/value

This paper provides a tentative understanding of the elements and dynamics of novelty generation through exaptation building on theoretical elaboration that is inductively triggered and stimulated by empirical evidence.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 4 January 2013

Anna Vikström, Anna Billström, Parviz Fazeli, Monica Holm, Kerstin Jonsson, Gunilla Karlsson and Peter Rydström

The purpose of this paper is to describe the collective exploration, process and knowledge production made in a learning study about solution chemistry.

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Abstract

Purpose

The purpose of this paper is to describe the collective exploration, process and knowledge production made in a learning study about solution chemistry.

Design/methodology/approach

Secondary school teachers conducted a learning study with variation theory as a guiding principle, supervised by a researcher. The relationship between teaching and learning was analyzed and evaluated in a learning study cycle of three lessons.

Findings

Critical aspects when teaching solution chemistry were identified, as well as enacted patterns of variation that significantly improved students’ learning. Examples of critical aspects were the particulate character of matter, especially the feature of “empty space” between particles, the connection between macroscopic phenomenon and sub‐microscopic explanations and the difference between answers with everyday language and scientific language.

Practical implications

The paper suggests that teachers in a learning study can produce new knowledge as well as use earlier research results when creating teaching activities that can improve their own practical work and students’ learning.

Originality/value

The study represents an example of research with the aim to improve teachers’ practice by generating knowledge in connection with teachers’ professional tasks.

Details

International Journal for Lesson and Learning Studies, vol. 2 no. 1
Type: Research Article
ISSN: 2046-8253

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Article
Publication date: 4 July 2016

Moses M. Solomon, Saviour A. Umoren, Aniekemeabasi U. Israel and Idongesit G. Etim

The purpose of this paper is to evaluate the performance of polypropylene glycol (PPG), as a corrosion inhibitor for aluminium corrosion in 0.5 M H2SO4 solution at 303-333…

Abstract

Purpose

The purpose of this paper is to evaluate the performance of polypropylene glycol (PPG), as a corrosion inhibitor for aluminium corrosion in 0.5 M H2SO4 solution at 303-333 K and the effect of addition of iodide ions on the corrosion inhibition efficacy of PPG.

Design/methodology/approach

The corrosion inhibition performance of PPG alone and on addition of iodide ions in the acid medium was evaluated using weight loss and electrochemical [electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR) and potentiodynamic polarization (PDP)] methods as well as surface analysis approach at 303-333 K. The morphology of the corroding aluminium surface without and with the additives was visualised using scanning electron microscopy (SEM). The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Findings

Results obtained showed that PPG moderately retarded the corrosion of Al in 0.5 M H2SO4 solution. Addition of KI to PPG is found to synergistically improve the inhibitive ability of PPG. From the variation of inhibition efficiency, K_ads, and E_a, with rise in temperature, physisorption mechanism is proposed for the adsorption of PPG and PPG + KI onto the Al surface in 0.5 M H2SO4 solution. Polarisation results showed that PPG and PPG + KI acted as mixed type inhibitor. The adsorption of PPG and PPG + KI, respectively, onto the metal surface followed El-Awady et al. adsorption isotherm model. SEM and water contact angle analysis confirmed the adsorption of PPG and PPG + KI on Al surface.

Research limitations/implications

The research is limited to aqueous acid environment in aerated condition, and all tests were performed under static conditions.

Practical implications

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

Originality/value

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

Details

Pigment & Resin Technology, vol. 45 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 7 September 2015

Zhiping Zhu, Xiaocui Jiao, Xueying Tang and Haiwei Lu

The purpose of this paper was to investigate the effects of SO42− concentration on the corrosion behaviour of T23 and T12 steels in simulated water chemistry condition…

Abstract

Purpose

The purpose of this paper was to investigate the effects of SO42− concentration on the corrosion behaviour of T23 and T12 steels in simulated water chemistry condition solution of 600 MW fossil-fired power boilers.

Design/methodology/approach

The influence and mechanism of SO42− ions on the pitting corrosion of T23 and T12 steels in simulated oxygenated treatment water chemistry solution was studied using electrochemical potentiodynamic polarization scans and electrochemical impedance spectroscopy.

Findings

The results showed that T23 and T12 were susceptible to pitting corrosion in the simulated solution with full SO42− concentration for the competitive adsorption of OH− and SO42− on the surface of steels. The pitting sensitivity of the steels improved with increasing SO42− concentration. The corrosion resistance for SO42− of T23 was stronger than that for T12.

Originality/value

This study is an attempt to provide direction for regulating the concentration of SO42− in boiler water and for selecting the material for boiler water wall tubes.

Details

Anti-Corrosion Methods and Materials, vol. 62 no. 5
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 April 2004

C. Giacomelli, F.C. Giacomelli, J.A.A. Baptista and A. Spinelli

The effect of oxalic acid (OA) on corrosion resistance of carbon steel in sulphuric acid pH=2.5‐6.0 solutions containing 10−7‐10−3M OA was investigated by means of…

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Abstract

The effect of oxalic acid (OA) on corrosion resistance of carbon steel in sulphuric acid pH=2.5‐6.0 solutions containing 10−7‐10−3M OA was investigated by means of potentiodynamic polarisation measurements and immersion tests. The results suggest that OA is a good corrosion inhibitor for carbon steel, exhibiting inhibition efficiencies (IE) ranging from 50 to 85 per cent in dilute 10−7‐10−5M OA solutions of pH>3.0, whereas for pH≤3.0 solutions, an increase in corrosion rate was found. Non‐accelerated experiments (weight loss tests) carried out by immersing carbon steel specimens into OA‐containing solutions during at least 6 h revealed only positive IE values, regardless of both solution pH and OA content. The results were explained considering the solution composition as function of pH.

Details

Anti-Corrosion Methods and Materials, vol. 51 no. 2
Type: Research Article
ISSN: 0003-5599

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Book part
Publication date: 18 March 2020

Niki Harré, Anis Azizi, Penny Brothers, Ties Coomber, Ellinor King, Andrea Michelle Mead, Sarah Saeckel, Manuel Vallée, Samantha Zi Lin Yeo and Yulun (Darren) Zhang

Since 2016, the authors have been teaching an interdisciplinary module on the global clothing industry to students enrolled in an introductory psychology course and a…

Abstract

Since 2016, the authors have been teaching an interdisciplinary module on the global clothing industry to students enrolled in an introductory psychology course and a second year chemistry course at the University of Auckland in New Zealand. In 2016, the module also involved third year chemistry students, and in 2017, second year sociology students and graduate students in English literature from the University of Stuttgart in Germany took part. The module has the following features: (1) it focuses on a complex industry with ramifications for social and environmental sustainability, (2) it involves an issue of direct relevance to the students, (3) students teach those from another discipline as “subject experts,” and (4) students are assessed on their learning within their home course. An evaluation of the 2018 iteration with psychology and chemistry students (N = 185) showed post-test decreases in participants’ materialistic values, increases in knowledge and concern about the social and environmental impacts of the clothing industry and reported changes to clothes buying practices. The authors discuss the institutional barriers faced and provide five recommendations for other university teachers considering integrating an interdisciplinary sustainability module into existing courses.

Details

Integrating Sustainable Development into the Curriculum
Type: Book
ISBN: 978-1-78769-941-0

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