| 1. |
- Butylina, Svetlana, et al.
(author)
-
Weathering of wood-polypropylene and wood-wollastonite-polypropylene composites containing pigments in Finnish climatic conditions
- 2015
-
In: Pigment & Resin Technology. - : Emerald Group Publishing Limited. - 0369-9420 .- 1758-6941. ; 44:5, s. 313-321
-
Journal article (peer-reviewed)abstract
- Purpose: The purpose of this paper is to study the resistance of wood-polypropylene and wood-wollastonite-polypropylene composites containing pigments to natural weathering.Design/methodology/approach: Natural weathering of composites was conducted in Finnish climatic conditions for one year. The colour of the composites was determined with a spectrophotometer, the morphology of the composite surface was analysed by scanning electron microscopy (SEM), and the changes in the polymer structure in surface layer of the composites were analysed with differential scanning calorimetry (DSC). Charpy impact strength was determined with an impact tester.Findings: The pigments used in this study reduced the colour change of the composites exposed to outdoor weathering as compared with the un-coloured composite. The carbon black pigment was more effective than the iron oxide pigment. Moreover, only the carbon black pigment was found to reduce the degradation of the surface layer of the composites. The addition of the carbon black pigment had a positive effect on the dimensional stability of the composites in a water absorption test. Only the combination of the carbon black pigment and wollastonite resulted in a composite which was capable to retain its Charpy impact strength both after one year of outdoor weathering and cyclic treatment.Research limitations/implications: This study is a part of continuous research on the development of wood-polymer composites (WPUs) suitable for outdoor applications in Finnish climatic conditions. The first part of the study, which has been published earlier, showed the results of weathering of composites in accelerated tests in comparison with 1,000 hours outdoor exposure during summer time (June and July). Outdoor weathering limited to 1,000 hours cannot give an objective view on the weathering behaviour of composites in Finnish climatic conditions. The results of the current study were obtained from one-year outdoor exposure of composites.Originality/value: The wood-polypropylene composite made with the combination of the carbon black pigment and wollastonite can be recommended for outdoor applications. The study provides useful information on the resistance of wood-polypropylene composites to weathering in Finnish climatic conditions.
|
|
| 2. |
- Sloot, Frea, et al.
(author)
-
Inventory of current EU paediatric vision and hearing screening programmes
- 2015
-
In: Journal of Medical Screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 22:2, s. 55-64
-
Journal article (peer-reviewed)abstract
- Objective: To examine the diversity in paediatric vision and hearing screening programmes in Europe. Methods: Themes for comparison of screening programmes derived from literature were used to compile three questionnaires on vision, hearing, and public health screening. Tests used, professions involved, age, and frequency of testing seem to influence sensitivity, specificity, and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists, and audiologists involved in paediatric screening in all EU full-member, candidate, and associate states. Answers were cross-checked. Results: Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% of these more than once. First measurement of VA varies from three to seven years of age, but is usually before age five. At age three and four, picture charts, including Lea Hyvarinen, are used most; in children over four, Tumbling-E and Snellen. As first hearing screening test, otoacoustic emission is used most in healthy neonates, and auditory brainstem response in premature newborns. The majority of hearing testing programmes are staged; children are referred after 1–4 abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists, or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand. Conclusion: Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1–4), and funding sources (8).
|
|
