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Article
Publication date: 1 March 1974

K. BHATTACHARYYA

This paper examines the implications of the findings of evaluative tests regarding the retrieval performance of natural language in various subject fields. It suggests…

Abstract

This paper examines the implications of the findings of evaluative tests regarding the retrieval performance of natural language in various subject fields. It suggests parallel investigations into the structure of natural language, with particular reference to terminology, as used in the different branches of basic science. The criteria for defining the terminological consistency of a subject are formulated and a measure suggested for determining the degree of terminological consistency.

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Journal of Documentation, vol. 30 no. 3
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 1 February 1978

Arthur Antony

The year 1977 was the first in the tenth collective period (1977‐1981) for Chemical Abstracts. Thus during that year the important and very voluminous Tenth Collective…

Abstract

The year 1977 was the first in the tenth collective period (1977‐1981) for Chemical Abstracts. Thus during that year the important and very voluminous Tenth Collective Index began to appear on library shelves, but as this review is being written in 1978 there are still volumes of the formula and chemical substance indexes that have to be added. Librarians will have recently received two Index Guides: one as part of the Ninth Collective Index, and the other as the first Index Guide for the tenth collective period ‐ to be supplemented annually, and finally superseded by the Index Guide which appears as part of the Tenth Collective Index.

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Reference Services Review, vol. 6 no. 2
Type: Research Article
ISSN: 0090-7324

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Article
Publication date: 2 March 2015

H. Abd El-Wahab

This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added…

Abstract

Purpose

This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added physically to organic coating.

Design/methodology/approach

Flame retardants are incorporated into polymeric materials either as additives or as reactive materials. Additive-type flame retardants are widely used by incorporating into polymeric materials by physical means. In this research, Schiff’s base (azomethine) compounds are added physically to alkyd paint as flame-retardant additives. Elemental analysis, infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to characterise the structure of the prepared Schiff’s base compounds. Thermal gravimetric analysis was used to evaluate their thermal stability. Experimental coatings were manufactured on a laboratory scale, and then applied by brush on wood and steel panels.

Findings

Results of an oxygen index value indicated that alkyd paints containing Schiff’s base compounds as additives exhibit very good flame-retardant effects. Also the physical, mechanical and corrosion resistance properties were studied to evaluate the drawbacks of the additives. The additives did not affect the flexibility of the paint formula. The gloss and the impact strength were decreased by the additives, but the hardness, adhesion and corrosion resistance were significantly improved by these additives.

Research limitations/implications

Alkyd resins are the most extensively used synthetic polymers in the coating industry. Nitrogen compounds are a small but rapidly growing group of flame retardants which are in the focus of public interest concerning environment-friendly flame retardants. So, the focus of this study is on Schiff’s base compounds as flame retardants and anticorrosive additives for alkyd resins to assess their applicability.

Practical implications

Schiff’s base compounds can be used as new additives in paint formulations to improve the flame-retardant and corrosion properties.

Originality/value

In recent years, there has been considerable interest in the nitrogen-based family of materials because they not only have a wide range of thermal and chemical stabilities, but can also provide improved thermal and flame-retardant properties to polymers. The present paper reports on the synthesis and characterisation of Schiff’s base compounds and their performance in alkyd resin coatings.

Details

Pigment and Resin Technology, vol. 44 no. 2
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 July 1982

Anne J. Walton

Thixotropy can be regarded as the loss of viscosity in a paint or other material that is brought about by mechanical agitation, and where the viscosity continues to…

Abstract

Thixotropy can be regarded as the loss of viscosity in a paint or other material that is brought about by mechanical agitation, and where the viscosity continues to decrease provided that this disturbance is continued for a period of time. Conversely, when the mechanical force is removed, the material then increases in viscosity and this recovery toward the initial structure continues to take place over a period of time. Sometimes the time dependency of the viscosity is vanishingly small so that the material is then properly referred to as pseudoplastic. In most of the literature, however, it is not usually possible to differentiate between thixotropy and true pseudoplasticity and therefore both kinds of structure are included in this review as they each are destroyed by mechanical agitation and recover when this is discontinued.

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Pigment & Resin Technology, vol. 11 no. 7
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 October 1963

D.J. CAMPBELL

In visiting more than a hundred special libraries and information units in Britain (not to use their resources but to study their methods) I have often been concerned by…

Abstract

In visiting more than a hundred special libraries and information units in Britain (not to use their resources but to study their methods) I have often been concerned by the inadequacy of the private indexing systems in use, although there were many exceptions. The classifications were often crude, and/or outdated, and/or quite insufficiently detailed, and were seldom provided with good subject indexes. Alphabetical subject‐heading indexes are more difficult to assess on a brief visit, but these were seldom detailed enough, so that fifty or more documents could be indexed under one heading. Seldom was there a separate subject‐headings list, and often no recognition of the need of one. Guidance for the user was very often poor.

Details

Aslib Proceedings, vol. 15 no. 10
Type: Research Article
ISSN: 0001-253X

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Article
Publication date: 1 September 1974

Heinz Rechmann

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to…

Abstract

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to corrosion with high strength and low specific gravity, to the white pigment, titanium dioxide, and titanium tetrachloride, a chemical intermediate. This paper reviews the manufacture of these materials and particularly deals with the properties and applications of titanium dioxide, which, by reason of its high refractive index, possesses outstanding lightening and hiding power, making it the first choice among white pigments.

Details

Pigment & Resin Technology, vol. 3 no. 9
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 8 January 2018

Xinlei Gao, Tingting Wang and Zhong Cheng

Ultra-high molecular weight polyethylene (UHMWPE) has an excellent performance and application value; however, as a tribological material, its main drawback is its poor…

Abstract

Purpose

Ultra-high molecular weight polyethylene (UHMWPE) has an excellent performance and application value; however, as a tribological material, its main drawback is its poor performance under dry friction, impacting its ability to work in high-speed dry friction conditions. Modification of UHMWPE can be carried out to overcome these issues. A significant number of inorganic materials have been used to modify UHMWPE and provide it with good tribological performance. However, thus far, there has been no systematic investigation into the methodology of modifying UHMWPE. The authors take a quantitative approach to determine the structure tribo-ability relationship and basic principles of screening of inorganic compounds suited to modify UHMWPE.

Design/methodology/approach

The tribological properties of modified UHMWPE using a series of inorganic additives have been qualitatively studied by the authors’ research group previously. In this study, basic quantitative structure tribo-ability relationships (QSTRs) of inorganic additives for modifying UHMWPE were studied to predict tribological properties. A set of 15 inorganic compounds and their tribological data were used to study the predictive capability of QSTR towards inorganic additives properties.

Findings

The results show that the anti-wear and friction-reducing properties of these inorganic compounds correlate with the calculated parameters of entropy and dipole moment. Increased entropy and smaller dipole moment can effectively improve the anti-wear and friction-reducing ability of inorganic compounds as UHMWPE additives. Additives with larger molecular weight, lower hardness and lower melting and boiling points provide good tribological properties for UHMWPE. For inorganic compounds to act as UHMWPE additives, the chemical bond should be less covalent and have more ionic character.

Research limitations/implications

Only 15 inorganic compounds and their tribological data were used to study the predictive capability of QSTR towards inorganic additives properties. If the samples number is more than 30, the other QSTR methodology can be used to study the modified UHMWPE, and the models finding can be more precise.

Practical implications

A QSTR model for modified UHMWPE has been studied systematically. While the results are not more precise and detailed, the model provides a new way to explore the modified UHMWPE characteristics and to reveal new insight into the friction and wear process.

Social implications

Because the method of studying tribological materials is entirely different from others, the authors want to present the works and discuss it with colleagues.

Originality/value

The paper presents a new method to study the modified UHMWPE. A QSTR is used to study the tribology capability of compounds from calculated structure descriptors. This study uses the Hartree–Fock ab initio method to establish a QSTR prediction model to estimate the ability of 15 inorganic compounds to act as anti-wear and friction-reducing additives for UHMWPE.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 9 October 2017

Milad Soleimani and Mohsen Shahandashti

Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as…

Abstract

Purpose

Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as waste recovery and treatment, that potentially present significant environmental impacts. Existing life-cycle assessments of bioconcrete are limited in the inventory and impact analysis; therefore, they do not consider all the steps involved in concrete production and the corresponding impacts. The purpose of this study is to extensively study the cradle-to-gate environmental impacts of all the production stages of two most common bioconcrete types (i.e. sludge-based bioconcrete and cement kiln dust-rice husk ash (CKD-RHA) bioconcrete) as opposed to conventional concrete.

Design/methodology/approach

A cradle-to-gate life-cycle assessment process model is implemented to systematically analyze and quantify the resources consumed and the environmental impacts caused by the production of bioconcrete as opposed to the production of conventional concrete. The impacts analyzed in this assessment include global warming potential, ozone depletion potential, eutrophication, acidification, ecotoxicity, smog, fossil fuel use, human toxicity, particulate air and water consumption.

Findings

The results indicated that sludge-based bioconcrete had higher levels of global warming potential, eutrophication, acidification, ecotoxicity, fossil fuel use, human toxicity and particulate air than both conventional concrete and CKD-RHA bioconcrete.

Originality/value

The contribution of this study to the state of knowledge is that it sheds light on the hidden impacts of bioconcrete. The contribution to the state of practice is that the results of this study inform the bioconcrete production designers about the production processes with the highest impact.

Details

Journal of Engineering, Design and Technology, vol. 15 no. 5
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 1 April 1976

Roberta A. Scull

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973…

Abstract

This compilation of over 500 United States Government bibliographies is the second annual supplement to BIBLIOGRAPHY OF UNITED STATES GOVERNMENT BIBLIOGRAPHIES 1968–1973 (Pierian Press). Due to the Government Printing Office backlog during 1974, many 1973 and 1974 titles are included in this 1975 Supplement, which should have appeared earlier.

Details

Reference Services Review, vol. 4 no. 4
Type: Research Article
ISSN: 0090-7324

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Article
Publication date: 1 March 2006

M. Abdallah, A.Y. El‐Etre, M.G. Soliman and E.M. Mabrouk

To study the effects of the sodium salts of molybdate, tungstate and monovanadate as well as some derivatives of Neville‐Winter acid azo dyes on the corrosion of carbon…

Abstract

Purpose

To study the effects of the sodium salts of molybdate, tungstate and monovanadate as well as some derivatives of Neville‐Winter acid azo dyes on the corrosion of carbon steel in 3.5 percent NaCl solution.

Design/methodology/approach

Open circuit potential measurement and potentiostatic polarization techniques have been used.

Findings

It was found that all the compounds had inhibition effects on carbon steel dissolution. Inhibition efficiency (IE) increased with increase in inhibitor concentration. The process of inhibition was attributed to the formation of an adsorbed film on the metal surface, which protects the metal against the corrosive medium. The adsorption of these compounds on the steel/chloride interface was found to follow Freundlich adsorption isotherm behaviour.

Originality/value

Proves the effectiveness of the sodium salts of molybdate, tungstate and monovanadate as well as some derivatives of Neville‐Winter acid azo dyes on the corrosion of carbon steel in 3.5 percent NaCl solution.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

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