Abstract
Outgassing of PTH PCBs at different stages of PCB production was studied with a modified IEC outgassing test, Draft June 1985, now included in IEC 326–2 Amendment No. 2, January 1988. Outgassing rate from single PTHs was quantitatively measured with a U‐tube manometer as a pressure of expanded steam escaped. Some technological parameters were taken into account and different comparisons were made: PCB production stage (drilling, copper and solder plating, reflowing) vs. outgassing rate, laminate thickness vs. outgassing rate. The contributions to outgassing of PTHs through PCB production, especially from copper and tin‐lead plating, are seen. On PCBs, drilled with different drills and soldered unpopulated on wave and drag soldering machines, outgassing faults were assessed. By multiple regression the relation between outgassing faults, hole wall roughness and plated copper thickness was calculated.
Jian Song, Zhiming Gao, Chenxi Liu and Wenbin Hu
This paper aims to study the effect of flow rate (0.42∼2.09 m/s) on the corrosion behavior of WB36CN1 steel pipe in the simulated secondary circuit water environment (170°C, 6…
Abstract
Purpose
This paper aims to study the effect of flow rate (0.42∼2.09 m/s) on the corrosion behavior of WB36CN1 steel pipe in the simulated secondary circuit water environment (170°C, 6 mg/L ethanolamine + 100 µg/L NaCl), for which an autoclave was used to simulate the secondary circuit environment for carrying out related experiments.
Design/methodology/approach
The corrosion behaviors were studied by electrochemical methods, morphological observations and elemental analysis.
Findings
As flow rate increases, the amplitude of the current noise fluctuates increased, noise resistance Rn and spectral noise resistance Rsn decreased, the shear stress on the surface of WB36CN1 steel increases, the oxygen content on the surface decreases, the roughness becomes smaller. Meanwhile, the energy of energy distribution plot is concentrated at high frequencies under the three flow conditions, the slopes of current power spectral density curve approach 0 db/decade. This means that the oxide on the surface becomes less and corrosion rate increases with increasing flow rate. The corrosion type of WB36CN1 steel was uniform corrosion; the degree of uniform corrosion is higher at high flow rate.
Originality/value
The effect of flow rate on the corrosion behavior of WB36CN1 steel pipe in the secondary circuit water environment was studied by using electrochemical methods in the laboratory. The effect mechanism of flow rate for corrosion behavior was obtained.
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Hong Men, Bin Sun, Xiao Zhao, Xiujie Li, Jingjing Liu and Zhiming Xu
The purpose of this study is to analyze the corrosion behavior of 304SS in three kinds of solution, 3.5 per cent NaCl, 5 per cent H2SO4 and 1 M (1 mol/L) NaOH, using…
Abstract
Purpose
The purpose of this study is to analyze the corrosion behavior of 304SS in three kinds of solution, 3.5 per cent NaCl, 5 per cent H2SO4 and 1 M (1 mol/L) NaOH, using electrochemical noise.
Design/methodology/approach
Corrosion types and rates were characterized by spectrum and time-domain analysis. EN signals were evaluated using a novel method of phase space reconstruction and chaos theory. To evaluate the chaotic characteristics of corrosion systems, the delay time was obtained by the mutual information method and the embedding dimension was obtained by the average false neighbors method.
Findings
The varying degrees of chaos in the corrosion systems were indicated by positive largest Lyapunov exponents of the electrochemical potential noise.
Originality/value
The change of correlation dimension in three kinds of solution demonstrated significant differences, clearly differentiating various types of corrosion.
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The Second Brazilian Printed Circuit Association Seminar will take place in Rio de Janeiro from 21–23 September 1988. Papers will be presented on the following topics:
Alexandra Stavrianoudaki, Christos Govaris, Kostas Magos, Eleni Gana, Stavroula Kaldi and Charoula Stahopoulou
The present study provides insight on Roma students' understandings and experiences during their participation in a learning program under the aegis of Future Literacy Approaches…
Abstract
The present study provides insight on Roma students' understandings and experiences during their participation in a learning program under the aegis of Future Literacy Approaches and reports on the range of cognitive and social skills which can be cultivated through such literacy experiences. A case study research design was applied with an after-school evening class attended by 12 Roma students in a region of Greece. Thematic analysis of the qualitative data indicates that Roma students' engagement in the Future Literacy tasks of the program strengthened the acquisition of skills that could be useful for their daily lives, including the capacity to construct their own representations of daily life, and finding creative solutions to real-life situations. Activities provided students with the space and time to express their aspirations for self-empowerment and changed life conditions in the future. Findings provide one way to address the urgent need for Roma to challenge marginalization through leveraging their own active roles as citizens.
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Consists of a series of nine articles under the same title. Each article provides a different slant on the hiring process. Outlines the legal position when hiring employees and…
Abstract
Consists of a series of nine articles under the same title. Each article provides a different slant on the hiring process. Outlines the legal position when hiring employees and concentrates on providing a framework for managers. Covers areas including job analysis and descriptions, where to advertise and recruit, selection criteria, the interview, testing, negotiating the offer of employment and references. Briefly describes trends in employment practices and ways to minimize potential litigation through best practice.
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Sharon R. Stines and Brian H. Kleiner
Maintains that although current trends are for individuals to take more personal responsibility, rather than rely on the company, there will still be a need for bosses and…
Abstract
Maintains that although current trends are for individuals to take more personal responsibility, rather than rely on the company, there will still be a need for bosses and employees. Comments on the hire of new employees, giving a list of ten points to be addressed by the employer. Sums up that the small business owner needs to use every tool to enable the right decision to be made, regarding hiring the first employee(s) for his business.
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Rashmila Gurumurthy and Brian H. Kleiner
Provides a framework for managers to approach the hiring process effectively. Looks at job analysis and the legal position when advertising and hiring new staff. Covers the…
Abstract
Provides a framework for managers to approach the hiring process effectively. Looks at job analysis and the legal position when advertising and hiring new staff. Covers the screening process and resumes and interviewing. Gives some basic suggestions to consider and ask at interview. Uses Microsoft as a case study. Briefly looks at referencing and stresses the importance of effective hiring for the successful operation of any company.
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Jennifer S. Ellerman and Brian H. Kleiner
Briefly states what a human resource policy is and looks at why employers need one. Cites five principal sources for determining the content and meaning of policies. Provides a…
Abstract
Briefly states what a human resource policy is and looks at why employers need one. Cites five principal sources for determining the content and meaning of policies. Provides a list of questions which employers should address within their document. Advocates the policy should be reviewed by the company attorney to ensure legal compliance and the advantage of employee discussion and feedback as it is implemented.
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Kimberly Buch and Jack Aldridge
This article identifies the psychological and behavioural effectsassociated with corporate downsizing and the managerial challenges theypresent. These challenges include renewing…
Abstract
This article identifies the psychological and behavioural effects associated with corporate downsizing and the managerial challenges they present. These challenges include renewing psychological contracts, reversing threat‐rigidity tendencies, building post‐downsizing teams, and creating new corporate cultures. A strategy for matching specific Organisation Development (OD) interventions to each challenge is proposed which might aid managers and consultants in providing interventions best suited to the needs of each organisation.