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Article
Publication date: 1 March 1991

M. Wolverton and B. Abies

This paper describes the tests performed to evaluate the solder capillary action which occurs within a gap between two solderable surfaces during soldering. The goal was…

Abstract

This paper describes the tests performed to evaluate the solder capillary action which occurs within a gap between two solderable surfaces during soldering. The goal was to determine the optimal gap distance for maximum capillary flow in the attainment of hermetic solder joints capable of withstanding extreme temperature cycles and various mechanical shocks. One of the test conditions was arranged so that the gap thicknesses would vary while the width of the gaps remained constant. In a second condition, the gap thicknesses remained constant while the gap widths varied. Three plating designs were evaluated. They were nickel plating; nickel overplated with gold; and nickel, copper intermediate, with tin overplate. The capillary action of all three plating combinations deposited onto aluminium specimens, with the gap configurations previously described, was evaluated. The capillary results were measured with X‐ray and microstructural data. End use solder joint designs were determined from the capillary results. These designs are shown and they include the best plating design for the application. In addition, an unexpected result was obtained that is useful for testing the solderability of all finishes—the Configured Capillary Solderability Test.

Details

Soldering & Surface Mount Technology, vol. 3 no. 3
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 14 March 2016

Vassilis Detsis, Georgios Efthimiou, Olga Theodoropoulou and Stavroula Siorokou

The purpose of this paper is to establish the effects on the survival of outplanted Abies cephalonica Loudon seedlings of seedling characteristics, site characteristics…

Abstract

Purpose

The purpose of this paper is to establish the effects on the survival of outplanted Abies cephalonica Loudon seedlings of seedling characteristics, site characteristics and management practices.

Design/methodology/approach

The study was carried out by repeatedly monitoring survival of seedlings during a five-year period as well as establishing statistical relationships with a set of variables belonging to the aforementioned categories. It took place in plots reforested after a wildfire in the Parnitha Mt. National Park, near Athens, Greece.

Findings

The odds of survival were found to be affected by bedrock type, dominant vegetation, initial seedling height and use of shading implements. Artificial shading was most important during the first year, site-related characteristics gained importance with increasing age and seedling height was of relatively constant importance. Shifts in temporal patterns of mortality and damage symptoms occurrence suggest that the mechanisms causing mortality changed with increasing age.

Practical implications

The use of large seedlings in reforestation projects involving A. cephalonica should be preferred. Shading improves survival but due to the high costs this technique could be reserved for unfavorable plots, e.g. on limestone. Planting A. cephalonica in marginal sites should be avoided.

Originality/value

The knowledge of the performance of A. cephalonica outplanted seedlings is very limited, while the need is increasing due to the spread of wildfires in this previously unaffected habitat.

Details

Management of Environmental Quality: An International Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 13 September 2011

Haken Keskin and Musa Atar

The purpose of this paper is to determine the impacts of impregnation with Imersol Aqua to red colour tone (RCT) of some softwood materials and varnishes.

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Abstract

Purpose

The purpose of this paper is to determine the impacts of impregnation with Imersol Aqua to red colour tone (RCT) of some softwood materials and varnishes.

Design/methodology/approach

For this purpose, test samples prepared from Scots pine (Pinus sylvestris Lipsky), Oriental spruce (Picea orientalis Link) and Uludağ fir (Abies Bornmülleriana Mattf.), which met the requirements of ASTM D 358, were impregnated with Imersol Aqua by short‐term, medium‐term and long‐term immersion techniques in accordance with ASTM D 1413 and producer's definition. After impregnation, surfaces were coated by synthetic, acrylic, water‐based and polyurathane varnishes in accordance with ASTM D 3023 standards. RCT values of samples after varnishing process were determined in accordance with ASTM D 2244.

Findings

It was found that RCT was the highest in Scots pine, long‐term dipping and synthetic varnish, and the lowest in Uludağ fir, short‐term dipping and water‐borne varnish. Considering the interaction of wood type, period of impregnation and type of varnish, RCT was the highest in pine, short term of dipping and acrylic varnish and the lowest in Oriental spruce, short term of dipping and synthetic varnish. So, impregnation process, impregnation period and varnishes applied during tests showed increasing impact for RCT value of Scots pine, Oriental spruce and Uludağ fir woods. This result must be taken into care in manufacture of wooden furniture and construction elements where RCT is important.

Research limitations/implications

The endurance of the protective coating (such as varnish) to external effects is limited and the lifetime of the coating is determined by the type and the severity of the effects to which it is exposed.

Practical implications

The impact of varnish type, wood material type and impregnation chemical on RCT can determine the usefulness of the massive wood materials where RCT values are important.

Originality/value

It is conjectured that especially for the manufacturers and consumers in the furniture, construction and decoration sector, the data obtained in this study will contribute to the making up of the deficiencies in the understanding of the subject.

Details

Pigment & Resin Technology, vol. 40 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Content available
Article
Publication date: 21 May 2021

Marion Charlier, Antoine Glorieux, Xu Dai, Naveed Alam, Stephen Welch, Johan Anderson, Olivier Vassart and Ali Nadjai

The purpose of this paper is to propose a simplified representation of the fire load in computational fluid dynamics (CFD) to represent the effect of large-scale…

411

Abstract

Purpose

The purpose of this paper is to propose a simplified representation of the fire load in computational fluid dynamics (CFD) to represent the effect of large-scale travelling fire and to highlight the relevance of such an approach whilst coupling the CFD results with finite element method (FEM) to evaluate related steel temperatures, comparing the numerical outcomes with experimental measurements.

Design/methodology/approach

This paper presents the setup of the CFD simulations (FDS software), its corresponding assumptions and the calibration via two natural fire tests whilst focusing on gas temperatures and on steel temperatures measured on a central column. For the latter, two methods are presented: one based on EN 1993-1-2 and another linking CFD and FEM (SAFIR® software).

Findings

This paper suggests that such an approach can allow for an acceptable representation of the travelling fire both in terms of fire spread and steel temperatures. The inevitable limitations inherent to the simplifications made during the CFD simulations are also discussed. Regarding steel temperatures, the two methods lead to quite similar results, but with the ones obtained via CFD–FEM coupling are closer to those measured.

Originality/value

This work has revealed that the proposed simplified representation of the fire load appears to be appropriate to evaluate the temperature of steel structural elements within reasonable limits on computational time, making it potentially desirable for practical applications. This paper also presents the first comparisons of FDS–SAFIR® coupling with experimental results, highlighting promising outcomes.

Details

Journal of Structural Fire Engineering, vol. 12 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 1 October 2003

José Antonio Gómez Hernández and Cristóbal Pasadas Ureña

The adoption of the information literacy (IL) agenda in Spain has been comparatively slow and fragmented due to cultural setbacks during the twentieth century. Since the…

1654

Abstract

The adoption of the information literacy (IL) agenda in Spain has been comparatively slow and fragmented due to cultural setbacks during the twentieth century. Since the late 1980s, however, developments in library services and staffing policies, reforms in education, and wide availability of ICTs, among other factors, have led to a brighter picture, with academic and public librarians all over the country engaged in IL activities for all types of users – though school libraries still lag far behind. The main problems still to be addressed seem to be much the same as in most comparable countries: IL as a responsibility for all learning facilitators, social awareness of lifelong learning needs, training of IL trainers, assessing the individual achievements and the institutional outcomes of IL training programmes, and a clear understanding of the remit and rationale for different literacies within the information society.

Details

Library Review, vol. 52 no. 7
Type: Research Article
ISSN: 0024-2535

Keywords

Open Access
Article
Publication date: 8 February 2018

Ismail Ismail, Muhammad Sohail, Hammad Gilani, Anwar Ali, Kiramat Hussain, Kamran Hussain, Bhaskar Singh Karky, Faisal Mueen Qamer, Waqas Qazi, Wu Ning and Rajan Kotru

The purpose of the study is to analyse the occurrence and distribution of different tree species in Gilgit-Baltistan, Pakistan, as a baseline for further inventories, and…

7752

Abstract

Purpose

The purpose of the study is to analyse the occurrence and distribution of different tree species in Gilgit-Baltistan, Pakistan, as a baseline for further inventories, and estimate the biomass per species and plot. Furthermore, it aims to measure forest biodiversity using established formulae for tree species diversity index, richness, evenness and accumulative curve.

Design/methodology/approach

Field data were collected, including stratification of forest sample plots. Statistical analysis of the data was carried out, and locally appropriate allometric equations were applied for biomass estimation.

Findings

Representative circular 556 forest sample plots of 1,000 m2 contained 13,135 trees belonging to nine tree species with a total aboveground biomass of 12,887 tonnes. Sixty-eight per cent of the trees were found between 2,600 and 3,400 masl; approximately 63 per cent had a diameter at breast height equal to 30 cm, and 45 per cent were less than 12 m in height. The Shannon diversity index was 1.82, and Simpson’s index of diversity was 0.813.

Research limitations/implications

Rough terrain, long distances, harsh weather conditions and location of forest in steep narrow valleys presented challenges for the field crews, and meant that fieldwork took longer than planned.

Practical implications

Estimating biomass in Gilgit-Baltistan’s forests using locally developed allometric equations will provide transparency in estimates of forest reference levels, National Forest Monitoring System in Pakistan and devising Reducing Emissions from Deforestation and Forest Degradation national strategies and for effective implementation.

Originality/value

This paper presents the first detailed forest inventory carried out for the dry temperate and semi-arid cold region of Gilgit-Baltistan, Pakistan.

Details

International Journal of Climate Change Strategies and Management, vol. 10 no. 4
Type: Research Article
ISSN: 1756-8692

Keywords

Article
Publication date: 8 April 2021

Andrew Speak, Mark Usher, Hilary Solly and Stefan Zerbe

The non-material benefits which people derive from ecosystems, cultural ecosystem services (CES), can be difficult to measure and quantify. This study aims to demonstrate…

Abstract

Purpose

The non-material benefits which people derive from ecosystems, cultural ecosystem services (CES), can be difficult to measure and quantify. This study aims to demonstrate the usefulness of social media analysis.

Design/methodology/approach

The widespread use of social media applications has provided a novel methodology for obtaining crowd-sourced data, which can reveal patterns in how social media users interact with urban greenspace and participate in place-making activities. This study explores how urban trees are represented in images tagged with the city of Bolzano, Italy, and uploaded over the course of a year to the image-sharing application Instagram.

Findings

A third of all the images contained some elements of green nature, with 3.1% of the images portraying urban trees as the main subject and 11% with urban trees as background features. Seasonal preferences for winter and summer scenes emerged. Accompanying text, in the form of hashtags and image descriptions, was mostly positive and showed how enthusiastically people describe urban nature. An assessment of the images in terms of CES revealed that beyond aesthetic factors and the inspiration to take photographs of nature, a wide range of CES are represented, reflecting the recognition of the benefits of urban trees by Instagrammers. The collection of images provided a unique snapshot of the city of Bolzano.

Practical implications

This reinforces the importance of urban trees within planning policy for providing sense of place, recreation and stress relief for residents and tourists.

Originality/value

The study builds on recent advances in social media research, focussing on the important field of urban CES.

Details

Journal of Place Management and Development, vol. 14 no. 4
Type: Research Article
ISSN: 1753-8335

Keywords

Article
Publication date: 1 September 1946

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the United States…

Abstract

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

Details

Aircraft Engineering and Aerospace Technology, vol. 18 no. 9
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 11 June 2018

Alexandra Rizhinashvili

There is no clear answer to the question as to what kind of humic substances (HSs) (fulvic acids (FAs) or humic acids (HAs)) is primarily responsible for colour of water…

Abstract

Purpose

There is no clear answer to the question as to what kind of humic substances (HSs) (fulvic acids (FAs) or humic acids (HAs)) is primarily responsible for colour of water in water bodies. To resolve this problem, the purpose of this paper is to compare optical properties of the samples of river water with solutions (considered as standard) containing HAs and FAs in different concentrations.

Design/methodology/approach

The author sampled two typical unpolluted rivers of Karelian Isthmus (Leningrad Region, North-Western Russia) with different water colours – Vyun with light-brown water and Kivioja with dark-brown water.

Findings

It is revealed that the shape of the light absorption curve for both rivers is similar to that of FAs. Among the coefficients, a 364 * is unsuitable for differentiation between HAs and FAs due to its wide transgression. In contrast, the E540 coefficient allows one to separate these groups of HSs very well. The E540 values of the river water samples categorise them as FAs. The values of a 440 * indicate that river waters, especially from Kivioja, contain FAs with a large molecular weight in comparison with soil FAs (up to 1.75-fold higher). It shows a distinct character of river water HSs, which is consistent with the published data.

Practical implications

The results outline a more direct approach to decision support in the sphere of ecological monitoring of river water.

Originality/value

The author has concluded that river waters are coloured by FAs.

Details

Management of Environmental Quality: An International Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 1 July 2014

Svetlana Butylina and Timo Kärki

The purpose of this paper is to study natural and accelerated weathering of wood-polypropylene (WF-PP) and wood-wollastonite-polypropylene composites made with and without…

Abstract

Purpose

The purpose of this paper is to study natural and accelerated weathering of wood-polypropylene (WF-PP) and wood-wollastonite-polypropylene composites made with and without carbon black.

Design/methodology/approach

Natural weathering was conducted in Ruokolahti, Finland in the time of year when solar radiation was maximal. The accelerated weathering tests included exposure to a xenon-arc source with and without spray, and a cyclic test consisting of water immersion–freeze–thaw stages.

Findings

Both the type of weathering and the formulation of the composite determined the degree of change in their properties. Weathering, including xenon-arc exposure with spray resulted in much higher changes of colour of non-pigmented composites compared to natural weathering or xenon-arc weathering without spray. Both UV irradiation and moisture had an adverse effect on the Charpy impact strength of non-pigmented composites. Carbon black containing composites performed better than non-pigmented composites.

Research limitations/implications

This study is a part of an ongoing research on the development of wood-polymer composites (WPCs) suitable for outdoor applications in Finnish climatic conditions. Outdoor weathering limited to 1,000 h cannot be used for the prediction of the service life of composites and was used here solely for comparative purposes.

Originality/value

This paper will help to understand the effect of different weathering factors on the behaviour of WF-PP and wood-wollastonite-polypropylene composites made with and without carbon black (as UV stabiliser). The study demonstrated that while accelerated weathering tests provided useful information on the resistance of WF-PP composites to different weathering factors, they cannot be used alone to predict the behaviour of WPCs meant for outdoor application.

Details

Pigment & Resin Technology, vol. 43 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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