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A good solder flux must simultaneously perform a number of important functions. It must promote thermal transfer to the area of the solder joint, enhance wetting of the solder on the base metal, and prevent oxidation of the metal surfaces at soldering temperatures. However, its primary task is to remove the tarnish layer from the metal joint that is about to be soldered. Despite the fact that the process of soldering electronic devices is a part of a multi‐billion dollar industry, the actual chemical reactions that occur during this cleaning process are not well documented. In the case of organic acid or water‐soluble fluxes, the flux reactions can be modelled by considering the interactions at the metal/metal oxide/electrolyte solution interface. Although such modelling systems have not frequently been applied to the behaviour of solder and fluxes, they are common for a number of other closely related chemical systems which are of practical interest, e.g., passivation layers on metals, electrochemical cells and metal oxide semiconductors. There are two types of reactions that can occur at the oxide/solution interface: acid‐base reactions and oxidation‐reduction reactions. The factors which affect the reaction rates and mechanisms are such variables as the structure of the metal oxide, temperature, pH, concentration of the electrolyte, and the chemical nature of the solute and solvent. By combining information about flux behaviour with available models of surface reactions, it should be possible to develop the theory of the flux reactions and to gain a better understanding of the factors which control the process.

This article investigates the sources of financial information used for decisions regarding the buying, holding and selling of ordinary shares. The results of this questionnaire‐based study indicate that the main source of information used by those who prepare annual reports is stockbroker advice, whereas users of such reports prefer communication with management. Preparers of annual reports support the notion that annual reports are a useful source of information, but users prefer the preliminary announcement. Preparers read the income statement more thoroughly, while users read the cash flow statement more thoroughly. The article also provides information on the qualitative criteria used for assessing the usefulness of accounting practices, and some comments on the importance of setting standards and the objectives of the South African Statements of Generally Accepted Accounting Practice.

The aim of this work is to investigate the decomposition behaviour of the activator species commonly used in the wave solder no-clean flux systems and to estimate the residue amount left after subjecting the samples to simulated wave soldering conditions.

Changes in the chemical structure of the activators were studied using Fourier transform infrared spectroscopy technique and were correlated to the exposure temperatures within the range of wave soldering process. The amount of residue left on the surface was estimated using standardized acid-base titration method as a function of temperature, time of exposure and the substrate material used.

The study shows that there is a possibility of anhydride-like species formation during the thermal treatment of fluxes containing weak organic acids (WOAs) as activators (succinic and DL-malic). The decomposition patterns of solder flux activators depend on their chemical nature, time of heat exposure and substrate materials. Evaporation of the residue from the surface of different materials (laminate with solder mask, copper surface or glass surface) was found to be more pronounced for succinic-based solutions at highest test temperatures than for adipic acid. Less left residue was found on the laminate surface with solder mask (∼5-20 per cent of initial amount at 350°C) and poorest acid evaporation was noted for glass substrates (∼15-90 per cent).

The findings are attributed to the chemistry of WOAs typically used as solder flux activators. The results show the importance WOA type in relation to its melting/boiling points and the impact on the residual amount of contamination left after soldering process.

The results show that the evaporation of the flux residues takes place only at significantly high temperatures and longer exposure times are needed compared to the temperature range used for the wave soldering process. The extended time of thermal treatment and careful choice of fluxing technology would ensure obtaining more climatically reliable product.

This paper aims to examine differential perceptions of lenders and investors on (1) the use, perceived usefulness, importance and adequacy of annual reports, (2) the importance of qualitative characteristics (QCs) and (3) the perceived impact of International Financial Reporting Standards (IFRS) on financial reporting quality (FRQ) in Sri Lanka.

A questionnaire survey study of practising professionals consisting of Sri Lankan investors (N = 214) and lenders (N = 235).

In relation to (1), lenders and investors rank three out of ten information sources ahead of the remaining seven: both include annual reports and personal knowledge. However, the highest average response for lenders is direct communication with clients, and for investors, it is stock market publications. Within annual reports, both decision-makers identify financial statements as the most useful part. Concerning (2), they both identified understandability as the most important QC followed by timeliness. Relevance ranked last, surprisingly. In relation to (3), both groups perceived that the new IFRS reporting environment improved the FRQ compared to the previous Sri Lanka Accounting Standards regime.

Ranking understandability as the most important QC in terms of decision usefulness contradicts IASB's categorisation. The authors provide empirical data on the perceived degree of success of adopting IFRS in a developing economy.

The authors design a decision-oriented (lending vs investing) and context-specific (IASB's financial reporting framework) questionnaire to examine the perceptions of key capital providers separately on the issues mentioned above in “Purpose” within a developing economy. The survey fits into two aspects of the decision-useful theory: useful to make what decisions and useful to whom.

This paper aims to examine the usefulness of disclosures provided by Egyptian firms in the management report from the viewpoint of financial analysts and institutional investors.

Institutional investors are surveyed to determine whether disclosures are meeting the needs of these financial statements’ users. The final sample consists of 78 financial analysts who work at stockbrokerage firms and 36 institutional investors who work in Egyptian banks and insurance companies.

The main findings reveal that investors view mandatory and voluntary disclosures differently. Some voluntary disclosures are more useful than mandatory disclosures, which highlights a gap between the regulations and users’ information needs. Moreover, the findings show that respondents consider information related to ownership structure more important than information on risks and firms’ future performance.

This study enriches the scientific debate on the usefulness of disclosures provided in the management report. It might also encourage other researchers to focus on investigating different types of information that may have a significant influence on the decision-making process.

The findings will be useful to regulators to improve the current rules of disclosures. In addition, these results will also be helpful to managers because they highlight the disclosure items that are considered important by users.

This study provides evidence on how users perceive the usefulness of information disclosed in the management reports for their decision-making in an emerging capital market. Even though previous studies investigated the usefulness of management reports, no one of them emphasized the users’ viewpoint.

The following list of contracts placed by the Air Ministry during September is extracted from the October issue of The Ministry of Labour Gazette

While discourse abounds regarding the potential impacts of sports mega events on host cities, existing ideologies about, strategies for, and systematic examinations of “legacy” effects are poorly understood. This chapter presents a sociological examination of the sport mega-event legacy measurement process.

In this chapter, we reflect on our own involvement in legacy evaluation in the context of the 2015 Pan/Parapan Am Games in Toronto to examine existing legacy measurement strategies, review their findings, and present a theoretical detour via the past for consideration in future sociological contributions to the legacy measurement process.

Data discussed in this chapter suggest a need for the creation of a more sociologically informed, methodologically robust and piecemeal rather than Utopian-oriented “report card” measurement device for legacy evaluation.

Based on the review of evidence, we contend that if sociologists of sport remain committed to keeping their roles, as public intellectuals, applied researchers or participatory activists in the sport for development/legacy nexus, those involved might do so with a greater attention to focusing on what Karl Popper (1961) refers to as piecemeal social engineering strategies and measurements, and attending to those legacies both on and off the event organizing committee radar screen.

The purpose of this paper is to investigate the decomposition behavior of binary mixtures of organic activators commonly used in the no-clean wave flux systems upon their exposure to thermal treatments simulating wave soldering temperatures. The binary blends of activators were studied at varying ratios between the components.

Differential scanning calorimetry and thermogravimetric analysis were used to study the characteristics of weak organic acid (WOA) mixtures degradation as a function of temperature. The amount of residue left on the surface after the heat treatments was estimated by gravimetric measurements as a function of binary mixture type, temperature and exposure time. Ion chromatography analysis was used for understanding the relative difference between decomposition of activators in binary blends. The aggressivity of the left residue was assessed using the acidity indication gel test, and effect on reliability was investigated by DC leakage current measurement performed under varying humidity and potential bias conditions.

The results show that the typical range of temperatures experienced by electronics during the wave soldering process is not sufficient for the removal of significant activator amounts. If the residues contain binary mixture of WOAs, the final ratio between the components, the residue level and the corrosive effects depend on the relative decomposition behavior of individual components. Among the WOA investigated under the conventional wave soldering temperature, the evaporation and removal of succinic acid is more dominant compared to adipic and glutaric acids.

The findings are attributed to the chemistry of WOAs typically used as flux activators for wave soldering purposes. The results show the importance of controlling the WOA content and ratio between activating components in a flux formulation in relation to its tendencies for evaporation during soldering and the impact of its residues on electronics reliability.

The results show that the significant levels of flux residues can only be removed at significantly higher temperatures and longer exposure times compared to the conventional temperature range used for the wave soldering process. The potential corrosion issues related to insufficient flux residues removal will be determined by the residue amount, its composition and ratio between organic components. The proper time of thermal treatment and careful choice of fluxing formulation could ensure more climatically reliable product.