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This paper aimed to synthesise some new selenium-containing pyrazole, thiazole and thiophene dyestuffs and investigate their application in dyeing polyester fabrics.

4,4′-Diselanediyl-bis-(2-methoxyaniline) was diazotized by acetic acid/sodium nitrite and coupled with active methylene components such as malononitrile, ethyl cyanoacetate and ethyl acetoacetate, and their corresponding hydrazono products were cyclised with hydrazine or phenyl hydrazine to obtain a series of arylazo-pyrazole dyestuffs. Furthermore, diazo-coupling reactions of the diazotized 4,4′-diselanediyl-bis-(2-methoxyaniline) were developed to obtain a new series of 2-amino-5-arylazo-thiazole- and 4-aryazo-3-hydroxy-2-substituted thiophene dyestuffs.

The structure of the synthesised dyestuffs was established and confirmed based on their elemental analysis and spectral data (infrared, proton nuclear magnetic resonance and mass spectroscopies). The synthesised selenium-containing dyestuffs were applied as disperse dyes on polyester fabrics by high temperature-pressure technique. The dyeing characteristics of these dyestuffs were evaluated, and they were found to exhibit good fastness properties.

A series of symmetrical diselenide dyestuffs containing pyrazole, thiazole or thiophene coupler components were synthesised. The authors studied their application for dyeing polyester fabrics; they are superior in terms of preparation, yield, purity and fastness properties.

CLAIMED to be able to carry loads as high as 1,800 lb/sq. in. with little self‐wear and negligible wear of the surfaces against which they are sliding, a new group of self‐lubricating materials have been developed by the Westinghouse Electric Co. in the U.S.A. They are metal based composites containing small percentages of a film former, called polytetrafluoroethylene, and a novel dry lubricant, called tungsten diselenide, and are available in both a silver and copper matrix which are totally and homogeneously impregnated with the dry lubricant and film former. The lubricant is held in small pockets throughout the metal or high polymer matrices and form dry films of self‐lubricating material on the metal surfaces rubbing against the composites. These dry films transfer to other metal surfaces as they come into rubbing contact with the coated metal surfaces. In this way, the film continually transfers back and forth to heal any tiny break or faults that may occur in the films.

The aim of this paper is to provide a review of the present‐day and anticipated future uses of lasers in the production of solar cells.

Following a brief introduction to photovoltaics (PV), this paper first describes the two main types of solar cell, crystalline silicon and thin film and then discusses the use of lasers in their manufacture. Finally, future developments are considered.

The paper shows that lasers are used in the manufacture of both crystalline silicon and thin film PV. Applications are many and varied, e.g. edge isolation, hole drilling, border deletion and selective doping but few are yet adopted universally across the industry. Significant future prospects exist for laser‐based processes, as solar cell manufacturers seek to improve conversion efficiency and reduce production costs.

The paper shows that lasers play a vital role in solar cell manufacture and many additional applications will arise as photovoltaic technology is further developed.

The purpose of this paper is to investigate the potential of the experimental building integrated photovoltaic (BIPV) façade to cover net energy use in the adjacent office room. Electricity generated by PV panels was intended to cover the energy demand for the mechanical ventilation and the supplementary lighting. Analyses were performed for two orientations of the façade (east and west) and two occupancy profiles considering one or two employees per one office room.

The study was conducted by carrying detailed numerical analyses of energy produced by the BIPV façade and its consumption in adjacent office room. Calculations of energy generated by PV panels were made using simulation programme ESP-r. Advanced model, used in analyses, take into account dependence of the main electrical parameters of photovoltaic cell from temperature.

The findings reveal that energy generated by photovoltaic panels during transitional and cooling seasons is sufficient for lighting and ventilation requirement. However during winter months BIPV facade can cover energy demand only for ventilation.

The paper provides an original analysis of experimental BIPV façade system as a source of on-site produced renewable energy to cover energy demand in offices building under certain climate conditions. The results reported in presented paper shows the potential of BIPV facades and display this potential in a context of building net energy balance.

The purpose of this paper is to present a preliminary work on extracting band gap information of materials from academic papers. With increasing demand for renewable energy, band gap information will help material scientists design and implement novel photovoltaic (PV) cells.

The authors collected 1.44 million titles and abstracts of scholarly articles related to materials science, and then filtered the collection to 11,939 articles that potentially contain relevant information about materials and their band gap values. ChemDataExtractor was extended to extract information about PV materials and their band gap information. Evaluation was performed on randomly sampled information records of 415 papers.

The findings of this study show that the current system is able to correctly extract information for 51.32% articles, with partially correct extraction for 36.62% articles and incorrect for 12.04%. The authors have also identified the errors belonging to three main categories pertaining to chemical entity identification, band gap information and interdependency resolution. Future work will focus on addressing these errors to improve the performance of the system.

The authors did not find any literature to date on band gap information extraction from academic text using automated methods. This work is unique and original. Band gap information is of importance to materials scientists in applications such as solar cells, light emitting diodes and laser diodes.

This study aims to propose a methodology by integrating three approaches, namely, internal core technology, external knowledge flow and industrial technology development to help companies improve their decision-making quality for technology planning and enhance their research and development (R&D) portfolio efficiency.

The primary focus of this study is thin-film solar technology and patent data is retrieved from the United States Patent and Trademark Office (USPTO) database. This study presents a methodology based on the proposed integrated analysis method, constructed with patent indicators, centrality analysis of social networks and main path analysis.

The results of this study can be itemized as – the core technological competency: companies involved in two specific technology fields have lower strength in R&D portfolio than leading companies with single-core technology. Knowledge flow: most companies in a network are knowledge producers/absorbers and technological development: diverse source and sink nodes were identified in the global main path during 1997-2003, 2004-2010 and 2011-2017.

Latecomer companies can emulate leaders’ innovation and enhance their technological competence to seek niche technology. Using the global main path, companies monitor outdated technologies that can be replaced by new technologies and aid to plan R&D strategy and implement appropriate strategic decisions avoiding path dependency.

The knowledge accumulation process helps in identifying the change of position and the role of companies; understanding the trend of industrial technology knowledge helps companies to develop new technology and direct strategic decisions. The novelty of this research lies in the integrated approach of three methods aiding industries to find their internal core technical competencies and identify the external position in the competitive market.

A PAPER to the Institution of Mechanical Engineers by Dr. A. A. Parry and Dr. L. A. Mitchell of the Central Electricity Generating Board (Paper P20/68) giving details of the authors' research on solid lubricants for use within gas‐cooled power reactors is published with the intention of inviting written discussion. We publish the main details of this paper; the complete version is available from the I.Mech.E.

Thin films of tellurium dioxide (TeO₂) and indium oxide (In₂O₃) mixtures were investigated for γ‐radiation dosimetry purpose. Samples were fabricated using thermal vacuum evaporation technique. The electrical properties of mixed oxides thin films [(TeO₂)_1−x(In₂O₃)_x, where x=0 and 10 per cent by weight] and their changes under the influence of γ‐radiation were investigated. Samples with contacts having a planar structure showed increase in the values of current with the increase in radiation dose up to a certain dose level. Thin films in the form of pn‐junctions were fabricated with (TeO₂)_1−x(In₂O₃)_x as p‐type material and sulphur as n‐type material. These pn‐junctions exhibited Zener diode behaviour. The current‐voltage characteristics for as‐deposited and γ‐irradiated samples were recorded. The level of response for all the fabricated devices was found to be highly dependent on the composition of the exposed material.

Space satellites have for years used solar cells for their source of electricity. However, the technology has been expensive and relatively inefficient in comparison with other energy sources for terrestrial applications. There is increasing pressure for the development of renewable energy sources in view of the pollution caused by fossil fuels and their increasing scarcity, and a growing number of organizations, particularly in the USA, are finding niches for economical applications. Further developments in sensors are also extending the possibilities. In the UK, work is not so far advanced, but there is a Government support programme and many organizations are working hard to bring in the solar energy revolution.